KINDAI UNIVERSITY


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MAEKAWA Masahiko

Profile

FacultyResearch Institute for Science and Technology / Graduate School of Science and Engineering Research
PositionProfessor
DegreeDoctor of Science
Commentator Guidehttps://www.kindai.ac.jp/meikan/336-maekawa-masahiko.html
URLhttp://www.kindai.ac.jp
Mail
Last Updated :2020/09/11

Education and Career

Education

  •   1981 04  - 1985 03 , Kinki University, Faculty of Science and Engineering
  •   1985 04  - 1987 03 , Kinki University, Graduate School of Chemistry
  •   1987 04  - 1990 03 , Kinki University, Graduate School of Chemistry

Academic & Professional Experience

  •   2010 04 ,  - 現在, Professor, Research Institute for Science and Technology, Kinki University
  •   2003 04 ,  - 2010 03 , Associate Professor, Research Institute for Science and Technology, Kinki University
  •   1999 04 ,  - 2003 03 , Assistant Professor, Research Institute for Science and Technology, Kinki University
  •   1990 04 ,  - 1999 03 , research associate, Research Institute for Science and Technology, Kinki University
  •   1995 08 ,  - 1996 08 , Postdoctoral Research Fellow, Department of Chemistry, The University of Liverpool

Research Activities

Research Areas

  • Nanotechnology/Materials, Inorganic and coordination chemistry, Coordination Chemistry

Research Interests

  • Orgamometallic Chemistry, Coordination Chemistry, Coordination polymers

Published Papers

  • Syntheses and structural characterizations of mononuclear Ir(III) hydride complexes with 2,2':6',2''-terpyridine in the κ2N,N' and κ3N,N',N'' coordination modes, M. Maekawa, K. Terada, S. Oda, K. Sugimoto, T. Okubo, T. Kuroda-Sowa, Inorganica Chimica Acta, Inorganica Chimica Acta, 514, - 119962, Jan. 2021 , Refereed
  • Intermolecular carbon-carbon bond formation followed by intramolecular cyclization of electrochemically generated magnesium anthracenes and esters in the presence of chlorotrimethylsilane, K. Matsumoto, M. Matsumoto, T. Hayashi, M. Maekawa, K. Nishiwaki, S. Kashimura, Electrochemitry, Electrochemitry, 88(4), 314 - 320, 2020 , Refereed
  • Spectroscopic characterization of valence tautomeric behavior in a cobalt-dioxolene complex using an ancillary ligand containing quinoline groups, T. Mibu, Y. Suenaga, T. Okubo, M. Maekawa, T. Kuroda-Sowa, Inorganic Chemistry Communications, Inorganic Chemistry Communications, 114, 107826, 2020 , Refereed
  • Self-assembly of Cu(I) metallomacrocycle and coordination polymers with 2,2':5',4''-terpyridine directed by anions and solvents, M. Maekawa, T. Hayashi, K. Sugimoto, T. Okubo, T. Kuroda-Sowa, Inorg. Chim. Acta, Inorg. Chim. Acta, 497, 119088, Nov. 2019 , Refereed
  • Crystal structure of a dinuclear Co complex with doubly bridged fluorides: di-μ-fluoride-bis{(2-pyridylmethyl)bis(2-quinolylmethyl)}amine dicobalt(II) bis (tetrafluoroborate), [Co2(μ-F)2(pbqa)2](BF4)2, Y. Suenaga, T. Mibu, T. Okubo, M. Maekawa, T. Kuroda-Sowa, X-ray Struct. Anal. Online, X-ray Struct. Anal. Online, 35(10), 61 - 62, 2019 , Refereed
  • Syntheses, structure and properties of di-nuclear Co complexes with bis(catecholate) ligands-effect of a quinoline ring in the terminal group, Y. Suenaga, T. Mibu, T. Okubo, M. Maekawa, T. Kuroda-Sowa, Polyhedron, Polyhedron, 171, 480 - 485, 2019 , Refereed
  • Controlled self-assembled coordination polymer and monomer by [Ni(mnt)(2)Cu4I4](2-), Sugimoto Kunihisa, Maekawa Masahiko, Kuroda-Sowa Takayoshi, ACTA CRYSTALLOGRAPHICA A-FOUNDATION AND ADVANCES, ACTA CRYSTALLOGRAPHICA A-FOUNDATION AND ADVANCES, 73, C181, 2017 , Refereed
  • Synthesis, Crystal Structure, and Electroconducting Properties of a 1D Mixed-Valence Cu(I)-Cu(II) Coordination Polymer with a Dicyclohexyl Dithiocarbamate Ligand, Kenji Nakatani, Kento Himoto, Yuki Kono, Yuuki Nakahashi, Haruho Anma, Takashi Okubo, Masahiko Maekawa, Takayoshi Kuroda-Sowa, CRYSTALS, CRYSTALS, 5(2), 215 - 225, Jun. 2015 , Refereed
  • 共結晶中に見られた安定な環状S6分子の構造, 杉本邦久, 藤原明比古, 上町裕史, 前川雅彦, 日本結晶学会誌,, 日本結晶学会誌,, 56(1), 49 - 53, 2014 , Refereed
  • Crystal structure of a dinuclear Co complex with doubly bridged fluoride and peroxo ligands: μ-fluoro μ-peroxo bis{tris(2-pyridylmethyl)amine}dicobalt(III) tris(tetrafluoroborate), [Co2(μ-F)(μ-O2)(tpa)2](BF4)3, Y. Suenaga, M. Inomata, K. Uwai, K. Okuda, T. Okubo, M. Maekawa, T. Kuroda-Sowa, X-ray Struct. Anal. Online, X-ray Struct. Anal. Online, 30, 57 - 58, 2014 , Refereed
  • Controlled self-assembled coordination polymer and monomer by [Ni(mnt)(2)Cu4I4](2-), Sugimoto Kunihisa, Maekawa Masahiko, Kuroda-Sowa Takayoshi, ACTA CRYSTALLOGRAPHICA A-FOUNDATION AND ADVANCES, ACTA CRYSTALLOGRAPHICA A-FOUNDATION AND ADVANCES, 70, C181, 2014 , Refereed
  • Tris(μ4-azepane-1-carbodithioato)bis(μ3- azepane-1-carbodithioato)-μ9-bromido-tetra-μ2- bromido-octacopper(I)copper(II), Takashi Okubo, Haruho Anma, Masahiko Maekawa, Takayoshi Kuroda-Sowa, Acta Crystallographica Section E: Structure Reports Online, Acta Crystallographica Section E: Structure Reports Online, 69(5), m275 - m276, May 2013 , Refereed
    Summary:The reaction of Cu(Hm-dtc)2 (H2m-dtc is azepane-1-carbodithioic acid), CuBr2 and methyl isothiocyanate yielded the title mixed-valence nonanuclear CuI/CuII compound, [Cu 9Br5(C7H12NS2) 5] or [CuI 8CuIIBr5(Hm-dtc)5], encapsulating a bromide anion in the center of the Cu9Br 4S10 cluster cage. The cage consists of a mononuclear CuII unit [Cu(Hm-dtc)2], three μ4-bridging Hm-dtc- ligands, eight CuI ions with distorted tetrahedral or trigonal pyramidal coordination geometries and four μ2-bridging bromide anions. The incorporated central bromide anion interacts with nine Cu ions with shorter Cu - Br separations than the sum of the van der Waals radii for Cu and Br.
  • Framework dimensionality of copper(I) coordination polymers of 4,4 '- bipyrimidine controlled by anions and solvents, Masahiko Maekawa, Toshi Tominaga, Kunihisa Sugimoto, Takashi Okubo, Takayoshi Kuroda-Sowa, Megumu Munakata, Susumu Kitagawa, CRYSTENGCOMM, CRYSTENGCOMM, 14(4), 1345 - 1353, 2012 , Refereed
    Summary:The reaction of [Cu(C2H4)(n)]NO3 with 4,4'-bipyrimidine (bpm) in Me2CO under C2H4 afforded a polymeric Cu(I)-bpm/C2H4 adduct [Cu-2(bpm)(C2H4)(NO3)(2)](n) (1) with an infinite 1-D zigzag chain structure. Similar reactions of [Cu(C2H4)(n)]ClO4 or [Cu(MeCN)(4)]BF4 with bpm in Me2CO under C2H4 afforded Cu(I)-bpm/C2H4 adducts {[Cu-3(bpm) (2)(C2H4) (2)](ClO4)(3)}(n) (2) and {[Cu-3(bpm)(2)(C2H4)(2)](BF4)(3)}(n) (3), respectively, which have an infinite 1-D zigzag ladder structure. It is interesting that two disordered ClO4- or BF4- anions are accommodated in the inside cavity of the ladder chains. In contrast, the reaction of [Cu(MeCN)(4)]BF4 with bpm in MeOH under C2H4 afforded a Cu(I)-bpm/C2H4 adduct {[Cu-4(bpm) (3)(C2H4) (3)(MeOH)](BF4)(4)center dot 2H(2)O center dot 3MeOH}(n) (4). Three Cu atoms are bridged by three bpm ligands to form a metallacalix[3] arene structure with three legs of C2H4. Furthermore, these metallacalix[3] arenes are linked through another Cu atom in the terminal N atom of bpm to produce a chiral 2-D sheet structure with space group P6(3). One BF4- anion is accommodated in the small triangular Cu-3 cavities, whereas three disordered BF4- anions are encapsulated in the large triangular Cu-3 cavities. In contrast to complex 4, [Cu(MeCN)(4)]BF4 was reacted with bpm in MeOH under Ar, and C2H4 gas was then bubbled into the resultant brown suspensions. The reaction solution was allowed to come to room temperature, and Cu(I)-bpm complex {[Cu-3(bpm)(3)](SiF6)(1.5)}(n) (5) was collected. The tetrahedral Cu atom is coordinated by two N atoms in the chelate site of bpm and two N atoms in the terminal sites of two other bpm ligands to form two racemic metallacalix[3] arene structures. It is noteworthy that these metallacalix[3] arenes are joined through the bpm ligands to afford a 3-D cage structure consisting of two right-handed and left-handed helix networks. One disordered SiF62- anion is accommodated in the inside cavity between two opposite metallacalix[3] arene structures. On the basis of these results, it has been concluded that BF4-, PF6-, ClO4- and SiF62- anions can serve as anion templates to self-assemble polymeric Cu(I) C2H4 adducts and a cage compound in complexes 2-5. The NO3- anion is ineffective as an anion template, as indicated by the higher coordination ability of the NO3- anion in complex 1. Additionally, solvent-dependent effects have been observed in the formation process: Me2CO can preferentially induce polymeric 1-D chain and 1-D ladder structures in complexes 1-3, whereas MeOH can produce 2-D sheet and 3-D cage structures by the linage of metallacalix[3]arene structures in complexes 4 and 5.
  • Novel Cu-I Ethylene Complexes with 6,6 '-Diphenyl-4,4 '-bipyrimidine Three-Dimensionally Self-Assembled by an Intermolecular pi-pi Stacking Interaction and a C-H center dot center dot center dot N Contact, Masahiko Maekawa, Toshi Tominaga, Takashi Okubo, Takayoshi Kuroda-Sowa, Megumu Munakata, EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, (28), 4225 - 4231, Oct. 2009 , Refereed
    Summary:Four novel Cu-I-Ph(2)bpm/C2H4 adducts [Cu(Ph(2)bpm)(C2H4)]X [X = BF4 (1a, 1b), ClO4 (2) and PF6 (3); Ph(2)bpm = 6,6'-diphenyl-4,4'-bipyrimidine] were prepared and they have been characterized by X-ray, H-1 NMR, IR and TG-DTA analyses. The molecular structures of Cu-I-Ph(2)bpm/C2H4 complexes la, 1b, 2 and 3 are essentially similar: the Cu atom is coordinated by two N atoms in the chelate site of Ph(2)bpm and the C=C bond of C2H4 in the trigonal-planar geometry. Interestingly, their crystal packing structures are much different from the connection manners of an intermolecular pi-pi stacking interaction and a C-H center dot center dot center dot N contact, resulting in the self-assembly of Cu-I-C2H4 adducts with a unique three-dimensional network structure. The X-ray, H-1 NMR, IR data support the assumption that the contribution of the larger Cu-I -> C2H4 pi back-donation bonding is induced by the electron-releasing phenyl group. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
  • Abrupt Spin Transitions and LIESST Effects Observed in Fe-II Spin-crossover Complexes with Extended pi-Conjugated Schiff-base Ligands Having N4O2 Donor Sets, Takayoshi Kuroda-Sowa, Zhong Yu, Yuka Senzaki, Kunihisa Sugimoto, Masahiko Maekawa, Megumu Munakata, Shinya Hayami, Yonezo Maeda, CHEMISTRY LETTERS, CHEMISTRY LETTERS, 37(12), 1216 - 1217, Dec. 2008 , Refereed
    Summary:Novel Fe-II complexes with N4O2 donor sets having, extended pi-conjugated aromatic rings, [Fe(qnal)(2)]center dot CH2Cl2 and [Fe(qnal)21, show abrupt spin transitions at 220 and 265 K, respectively. Both complexes show LIESST effects below 80 K.
  • Porous copper(I) complexes of 2,11-dithia[3.3]paracyclophane: desorption and adsorption of guest molecules, SQ Liu, H Konaka, T Kuroda-Sowa, Y Suenaga, H Ito, GL Ning, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 357(12), 3621 - 3631, Sep. 2004
    Summary:Four copper(I) complexes of 2,11-dithia[3.3]paracyclophane (dtpcp), [CuI(dtpcp)] . MeCN (1), [CuBr(dtpcp)] . MeCN (2), [CuCl(dtpcp)] . MeCN (3) and [Cu2I2(dtPCP)(2)] . Me-thf (4) (Me-thf = 2-methyltetrahydrofuran), have been synthesized and their molecular structures determined by X-ray crystallography. Complexes I and 2 are isostructural, and exhibit 31) networks with elliptical channels along a-axis, which are constructed by dtpcp molecules bridging zigzag CuI and CuBr chains, respectively. Complexes 3 and 4 are 21) porous sheet networks constructed by bridging the zigzag copper-dtpcp chains via rhombic ring of Cu2X2 (X = Cl or 1). All sheets in 3 are packed in an eclipsed manner through pi-pi stackings to generate channels along the a-axis. However, the 2D porous sheets in 4 are packed in an offset mode such that channels are not formed along c-axis. Complexes I and 2 can reversibly incorporate guest acetonitriles without collapse of structures, and the original frameworks of I and 2 are completely recovered after incorporation of guests which are confirmed by X-ray powder diffraction (XRPD) pattern and H-1 NMR spectrum. Additionally, complex I exhibits selectivity in size and polarity for guest inclusion. (C) 2004 Elsevier B.V. All rights reserved.
  • Silver(I) complexes of dibenzo-18-crown-6-ether having cation-pi and pi-pi interactions, M Wen, M Munakata, Y Suenaga, T Kuroda-Sowa, M Maekawa, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 332, 18 - 24, Apr. 2002 , Refereed
    Summary:Three silver(I) complexes of dibenzo-18-crown-6-ether (DB[18]C6), [Ag(DB[18]C6)(ClO4)](THF) (1), [Ag(DB[18]6)(CF3SO3)](2)-(acetone), (2) and [Ag(DB[IS]C6)(CF3COO)](2)(AgCF3COO)(2) (3) have been synthesized in different solvents and characterized structurally. In each complex, silver ions prefer an octahedral coordination geometry and form close dinuclear complex with DB[18]C6 based on cation-pi interaction in eta(2)-fashion. In particular, the coordination unit involving a bonding at an oxygen group and pi-pi bonding between two benzene rings is quite unique. (C) 2002 Elsevier Science B.V. All rights reserved.
  • Crystal Structure of eta(5)-pentamethylcyclopentadienyl-eta(6)-toluene rhodium tetrafluoroborate, [Rh(Cp*)(eta 6-C6H5Me)](BF4)(2) (Cp* = eta(5)-C5Me5), M Maekawa, N Hashimoto, T Kuroda-Sowa, Y Suenaga, M Munakata, ANALYTICAL SCIENCES, ANALYTICAL SCIENCES, 17(11), 1361 - 1362, Nov. 2001 , Refereed
    Summary:Crystal structure of eta<sup>5</sup>-pentamethylcyclopentadienyl-eta<sup>6</sup>-toluene Rhodium tetrafuloroborate,[Rh(Cp<sup>*</sup>)(eta<sup>6</sup>-C<sub>6</sub>H<sub>5</sub>Me)](BF<sub>4</sub>)<sub>2</sub>(Cp<sup>*</sup>=eta<sup>5</sup>-C<sub>5</sub>Me<sub>5</sub>)
  • Unsymmetrical oxygenation products of [Pd(mnt)(2)](2)-: Syntheses and crystal structures of (Bu4N)(2)[Pd(mnt){O2S2C2(CN)(2)}] and one-dimensional coordination polymer (Bu4N)(2)[AgPd(mnt) {O2S2C2(CN)(2)}](2) (mnt=1,2-dicyano-1,2-ethylenedithiolato), K Sugimoto, T Kuroda-Sowa, M Maekawa, M Munakata, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 73(2), 391 - 394, Feb. 2000 , Refereed
    Summary:Oxidation of [Pd(mnt)(2)](2-) by H2O2 produces a sulfonyl-containing [Pd(mnt){O2S2C2(CN)(2)}](2-) (1(2-)). Addition of AgClO4 to 1(2-) results in the formation of [AgPd(mnt){O2S2C2(CN)(2)}](2)(2-) (2(2-)). Both compounds crystallize with a bulky cation Bu4N+ to form (Bu4N)(2)1 and (Bu4N)(2)2, which are characterized by single crystal X-ray analyses. 1(2-) retains a planar structure except for the sulfonyl oxygen atoms. The electronic absorption band observed at 387 nm (sh) is assigned to d-d transition. 2(2-) has a double-decker structure consisting of two [Pd(mnt){O2S2C2(CN)(2)}](2-) anions bridged by two Ag(I) ions through Ag-S bonds. Two terminal CN groups in 2(2-) coordinate to the neighboring Ag(I) ions, forming a one-dimensional chain structure. Crystallographic data are as follows. (Bu4N)(2)1: PdS4O2N6C40H72, triclinic, P (1) over bar, a = 12.145(2), b = 10.991(3), c = 10.156(2) Angstrom, alpha = 65.09(2), beta = 88.93(2), gamma = 84.97(2)degrees, Z = 1. (Bu4N)(2)2: Ag2Pd2S8O4N10C48H72, monoclinic, P2(1)/c, a = 9.649(2), b = 13.235(2), c = 25.107(2) Angstrom, beta = 91.03(1)degrees, Z = 2.
  • Three-dimensional silver((]G0001[))co-ordination polymer with pocket structures(共著), ┣DBJ. Chem. Soc., Dalton Trans.(/)-┫DB, ┣DBJ. Chem. Soc., Dalton Trans.(/)-┫DB, (20), 3620 - 3623, 2000
  • Synthesis and crystal structure of tetranuclear copper(I) and silver(I) complexes bridged by 2-amino-1,3,4-thiadiazole (atdz): [Cu-4(atdz)(6)](ClO4)(4) center dot 2CH(3)OH and [Ag-4(atdz)(6)](ClO4)(4), M Maekawa, M Munakata, T Kuroda-Sowa, Y Suenaga, K Sugimoto, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 290(2), 153 - 158, Jul. 1999
    Summary:Two novel tetracopper(I) and tetrasilver(I) complexes [Cu-4(atdz)(6)](ClO4)(4). 2CH(3)OH (1) and [Ag-4(atdz)(6)](ClO4)(4) (2), have been prepared using 2-amino-1,3,4-thiadiazole (atdz), and their crystal structures and properties have been determined. On each tetranuclear complex, two Cu or Ag atoms (M) are bridged by two atdz ligands to form a six-membered N2M2N2 framework. The two N2M2N2 frameworks are in parallel linked by another atdz ligand to provide the tetranuclear structure with a rectangular M-4 core. The four Cu or Ag atoms possess a trigonal-square geometry. The two adjacent M...M separations are (3.096(1) and 3.412(1) Angstrom) and (3.316(2) and 3.658(2) Angstrom) for 1 and 2, respectively. On both tetranuclear complexes there are two species of hydrogen bonds between the ClO4- anions and the NH2 group of atdz ligands. It is proposed that the hydrogen bonds are related to the stabilization of the tetranuclear structure during the crystallization process. (C) 1999 Elsevier Science S.A. All rights reserved.
  • A novel eight-membered Cu4I4 ring supported by sulfur atoms of an M(mnt)(2) moiety: syntheses and crystal structures of (NBu4n)(2)[M(mnt)(2)Cu4I4] (M = Ni, Pd, Pt; mnt = 1,2-dicyano-1,2-ethylenedithiolato) with doubly-bridged one-dimensional chain structures, K Sugimoto, T Kuroda-Sowa, M Maekawa, M Munakata, CHEMICAL COMMUNICATIONS, CHEMICAL COMMUNICATIONS, 455-456(5), 455 - 456, Mar. 1999 , Refereed
    Summary:Crystal structure analyses of the title compounds revealed that they have almost the same structure with a novel eight-membered Cu4I4 ring supported by an M(mnt)(2) moiety, two cyano groups out of the four of which coordinate to two copper(I) ions in neighboring molecules, resulting in the formation of a unique doubly-bridged one-dimensional chain structure.
  • Synthesis and crystal structure of tetranuclear copper (I) and silver (I) complexes bridged by 2-amino-1, 3, 4-thiadiazole (atdz) : [Cu4(atdz)6](CIO4)2・ 2CH3OH and [Ag4(atdz)6
  • Synthesis and crystal structure of dinuclear palladium(I) dppm complex with 4-mercaptopyridine in the thione mode. [Pd-2(mu-dppm)(2)(HpyS)(2)](ClO4)(2)center dot CH3OH, M Maekawa, M Munakata, T Kuroda-Sowa, Y Suenaga, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 281(1), 116 - 119, Oct. 1998 , Refereed
    Summary:The reaction of [Pd-2(mu-dppm) (2)](2+) With 4-mercaptopyridine (pySH) in methanol produced the dipalladium(I) dppm complex [Pd-2( mu-dppm)(2)(HpyS)(2)] (ClO4)(2). CH3OH (1), and its structure and properties were characterized by a single crystal X-ray structure analysis, UV-Vis, IR and NMR spectra. The two Pd atoms are doubly-bridged by two dppm ligands to form an eight-membered Pd2P4C2 framework, in a twist-chair conformation. The HpyS ligand in the thione mode is also coordinated to each Pd atom, forming the Pd2P4C2 framework in a side-by-side conformation. The average Pd-S and Pd-P distance is 2.403(2) and 2.299(2) Angstrom, respectively. The Pd-Pd distance of 2.6645(6) Angstrom is shorter than that (2.75 Angstrom) in Pd metal, which is indicative of a direct Pd-Pd bond. The results of IR, NMR and W-Vis spectra supported that the dinuclear structure of 1 is kept in solid and solution. (C) 1998 Elsevier Science S.A. All rights reserved.
  • S center dot center dot center dot S contact-assembled tetrathiafulvalene derivatives of copper(I) and silver(I) co-ordination polymers and organic radical cation salt, LP Wu, J Dai, M Munakata, T Kuroda-Sowa, M Maekawa, Y Suenaga, Y Ohno, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 3255-3261.(19), 3255 - 3261, Oct. 1998 , Refereed
    Summary:The reactions of 2-[4,5-bis(methylsulfanyl)-1,3-dithiol-2-ylidene]-4,5-bis(2-cyanoethylsulfanyl)-1,3-dithiole (CM-TTF) with copper(II) and silver(I) salts resulted in the isolation and structural characterization of S ... S contact assembled co-ordination polymers, [Cu(CM-TTF)][ClO4]. thf 1 and [Ag(CM-TTF)(CF3SO3)] 2, and radical cation salt, [CM-TTF][CuCl2] 3. Both 1 and 2 are 1:1 metal-ligand complexes in which the metal ions and CM-TTF molecules are alternately linked forming two-dimensional networks and infinite linear chain structures, respectively, which are further reinforced by close intermolecular S ... S interactions. The structure of 3 consists of segregated stacks of CM-TTF.+ donors and CuCl2- accepters associated via short S ... Cl contacts leading to an alternate donor-acceptor-donor columnar arrangement. The complexes were additionally characterized by IR, UV/VIS and ESR spectra as well as electrical resistivity measurements. All the complexes and their corresponding air-oxidized species are poor electrical conductors, but they show typical charge-transfer ESR signals and electronic absorptions. Complex 3 was found to exhibit transition from antiferro- to ferro-magnetic coupling upon air oxidation.
  • Crystal structure of tetranuclear palladium complex bridged by bis(diphenylphosphino)methane, [Pd-4(mu-dppm)(4)(mu-Cl)(2)](ClO4)(2)center dot bpe, M Maekawa, M Munakata, T Kuroda-Sowa, Y Suenaga, ANALYTICAL SCIENCES, ANALYTICAL SCIENCES, 14(2), 451 - 453, Apr. 1998 , Refereed
  • Mercury(II) complexes of 4,5-ethylenedithio-1,3-dithiole-2-thione, having S center dot center dot center dot S and S center dot center dot center dot Cl contact assembled ribbon structure, J Dai, M Munakata, GQ Bian, QF Xu, T Kuroda-Sowa, M Maekawa, POLYHEDRON, POLYHEDRON, 17(13-14), 2267 - 2270, 1998 , Refereed
    Summary:Two mercury(II) complexes of 4,5-ethylenedithio-1,3-dithiole-2-thione (C5H4S5), [Hg-2(C5H4S5)(2)Cl-4] (1) and [Hg-2(C5H4S5)(2)Br-4] (2), were synthesized and the structure of complex 1 was characterized crystallographically. Complex 1 has a dimeric structure, in which each mercury atom takes a tetrahedral geometry and is coordinated by two bridging chloride, one terminal chloride and one thiocarbonyl sulfur atom (C=S) of the ligand. These dimers are further packed to form a one dimensional ribbon structure via intermolecular S ... S and S ... Cl contacts. All of the ligands in the ribbon are co-planar and weakly conjugated. (C) 1998 Elsevier Science Ltd. All rights reserved.
  • S center dot center dot center dot S contact-assembled silver(I) complexes of 4,5-ethylenedithio-1,3-dithiole-2-thione having unique supramolecular networks, J Dai, T KurodaSowa, M Munakata, M Maekawa, Y Suenaga, Y Ohno, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 2363(13), 2363 - 2368, Jul. 1997 , Refereed
    Summary:Two silver(I) complexes of 4,5-ethylenedithio-1,3-dithiole-2-thione (C5H4S5), [{Ag(C5H4S5)(3)}ClO4 . CH3CN](2) and [Ag(C5H4S5)CF3SO3](infinity) have been synthesized and characterized crystallographically. They have unique dimeric and two-dimensional structures respectively and are assembled by S ... S contacts. The finding of the shortest S ... S contacts (3.284 and 3.262 Angstrom) in these complexes indicated that the co-ordination linkage in metal complexes containing these types of sulfur donor compounds could be expected to control the intra- or inter-molecular interactions. The co-ordination mode of the C5H4S5 ligand has also been discussed.
  • Structure and H-1 NMR study of copper(I) complex with ethylene and tetramethylethylenediamine, Y Suenaga, LP Wu, T KurodaSowa, M Munakata, M Maekawa, POLYHEDRON, POLYHEDRON, 16(1), 67 - 70, 1997 , Refereed
    Summary:A ternary copper(I) complex with ethylene and tetramethylethylenediamine (tmen) has been prepared and the structure characterized by the single crystal X-ray method. The copper atom is coordinated to two nitrogen atoms of tmen and an ethylene molecule in a trigonal-planar arrangement. The C=C bond distance of 1.36(1) Angstrom is slightly longer than that of the free ethylene (1.33 Angstrom ). In the H-1 NMR study, chemical shifts of ethylene protons at 5.46 ppm move upfield (4.16 ppm) upon coordination to copper(I). This indicates that the pi back donation from copper to the ethylene is rather weak compared with other metal-ethylene systems. Copyright (C) 1996 Elsevier Science Ltd
  • In situ FT-IR study of polynuclear peroxo complexes formed in a H2O2-cerium(IV) decatungstate anion (CeW10O(36)(8-)) reacting system, R Shiozaki, E Nishio, M Morimoto, H Kominami, M Maekawa, YA Kera, APPLIED SPECTROSCOPY, APPLIED SPECTROSCOPY, 50(4), 541 - 544, Apr. 1996 , Refereed
  • Spectroscopic investigation of a series of sodium lanthanide decatungstates, Na(7)H(2)Ln(III)(W5O18)(2)center dot nH(2)O (Ln: La-Yb): The contribution of 4f(n) electrons to bonding interaction among Ln(III) and polyoxotungstates, R Shiozaki, A Inagaki, A Nishino, E Nishio, M Maekawa, H Kominami, Y Kera, JOURNAL OF ALLOYS AND COMPOUNDS, JOURNAL OF ALLOYS AND COMPOUNDS, 234(2), 193 - 198, Feb. 1996 , Refereed
    Summary:A series of sodium lanthanide decatungstates, Na(7)H(2)Ln(III)(W5O18)(2) . nH(2)O (Ln = La-Yb) was synthesized and characterized by spectroscopic analyses. The W-183-NMR chemical shifts for the W adjacent to Ln(III) correlated well. with the contact parameter in the lanthanide induced shifts, (Sz), which had been theorized by Golding. The FT-Raman stretching frequencies for the Ln-O-W bonding also correlated with the theoretical magnetic moments induced from the 4f(n) electrons in the lanthanide ions in addition to the ionic radii of Ln(III). A direct contribution of the 4f(n) electrons to the bonding interaction among Ln(III) and the oxotungstates is suggested.
  • Three-fold interpenetrating diamondoid frameworks with pi-pi stacking of alternate coordinated and uncoordinated ligands: Crystal structures of copper(I) coordination compounds, [Cu(DMTPN)(2)]X(DMTPN)(thf) (DMTPN=2,5-dimethylterephthalonitrile; X=BF4, ClO4), T KurodaSowa, M Yamamoto, M Munakata, M Seto, M Maekawa, CHEMISTRY LETTERS, CHEMISTRY LETTERS, 349(5), 349 - 350, 1996 , Refereed
    Summary:Two novel coordination polymer compounds, [Cu(DMTPN)(2)]X(DMTPN)(thf) (DMTPN = 2, 5-dimethylterephthalonitrile, X = BF4 (1) and ClO4 (2)) are prepared and characterized by single crystal X-ray analysis; both are isostructural and have three-fold interpenetrated diamondoid structure with pi-pi stacking column of alternate coordinated and uncoordinated DMTPN.
  • Synthesis and structure of a three-dimensional lanthanum(III) coordination polymer with mellitate, {La-2[C-6(COO)(6)](H2O)(9)}.2H(2)O, LP Wu, M Munakata, M Yamamoto, T KurodaSowa, M Maekawa, JOURNAL OF COORDINATION CHEMISTRY, JOURNAL OF COORDINATION CHEMISTRY, 37(1-4), 361 - 369, 1996 , Refereed
    Summary:The crystal and molecular structure of a lanthanum(III) mellitate, La2C12H22O23, has been determined by X-ray structural analysis using a combination of direct and heavy atom methods. The complex crystallizes in the monoclinic space group P2(1)/n with unit-cell dimensions of a = 6.723(4), b = 11.368(5), c = 29.813(4) Angstrom and beta = 95.851(3)degrees. Block-diagonal least-squares refinement using automated diffractometer-collected data resulted in R = 2.5 and R-w = 3.4. The crystal structure consists of layers perpendicular to the a axis. Each layer is formed by an extended network of lanthanum ions coordinated with mellitate anions and water molecules, and linked through a complex three-dimensional hydrogen-bonding network. Among the six carboxylate groups of the mellitate anion, five form coordination bonds to six lanthanum atoms. The two independent lanthanum ions are both nine-coordinate and the configuration around lanthanum is a tricapped trigonal prism with the La-O bond distances ranging from 2.457 Angstrom to 2.704 Angstrom.
  • Synthesis and crystal structure of a tetranuclear bis(diphenylphosphino)methane palladium complex capped by a mu(4)-bonded sulfide: [Pd-4(mu-dppm)(4)(mu(4)-S)]center dot 4(CH3)(2)CO, M Maekawa, M Munakata, T KurodaSowa, T Goto, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 239(1-2), 159 - 163, Nov. 1995 , Refereed
    Summary:We have prepared the tetranuclear palladium complex [Pd-4(mu-dppm)(4)(mu(4)-S)] (1) capped by a mu(4)-bonded sulfide and crystallographically characterized it. Four Pd atoms are bridged by four dppm ligands to form the rectangular Pd-4 core, which are capped by the mu(4)-bonded sulfide from the side above the Pd-4 plane. It was suggested that the mu(4)-bonded S atom is derived from the cleavage of the C-S bond of diethyldithiocarbamate. Complex 1 has the following crystal data: monoclinic, C2/c, a = 30.503(8), b = 12.061(2), c = 31.686(7) Angstrom, beta = 118.25(2)degrees, V = 10268(8) Angstrom(3), Z = 4, R = 0.051, R(w) = 0.070.
  • Crystal structure and magnetic properties of manganese(II) mellitate, [Mn-2{C-6(COO)(6)}(H2O)(6)][Mn(H2O)(6)]center dot 2H(2)O with two-dimensional layered structure and three-dimensional hydrogen bonding networks, LP Wu, M Yamamoto, T KurodaSowa, M Maekawa, J Fukui, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 239(1-2), 165 - 169, Nov. 1995 , Refereed
    Summary:The crystal and molecular structure of manganese(II) mellitate, [Mn-2{C-6(COO)(6)}(H2O)(6)][Mn(H2O)(6)]. 2H(2)O, has been determined by X-ray structure analysis, The complex crystallizes in the monoclinic system, space group C2/c, with cell constants a = 23.298(3), b = 6.456(3), c = 17.072(2) Angstrom, beta = 101.01(1)degrees and Z = 4. The structure was solved and refined to R = 0.029 (R(w) = 0.036). There are two types of manganese ions in the structure. Mn(1) is situated on a crystallographic center of symmetry and bound to six water molecules while Mn(2) is coordinated octahedrally by three water molecules and three carboxylate oxygen atoms. The major structure feature is that the polyanion formed by Mn(2) ions and the mellitate hexanions with composition of [Mn-2{C-6(COO)(6)}(H2O)(6)](2n-)(n) possesses a two-dimensional layered structure which is linked through a complex three-dimensional hydrogen bonding associated with the Mn(1) cation [Mn(H2O)(6)](2+) and the water of crystallization. Analysis of variable-temperature magnetic susceptibility data (5.0-300 K) shows that the complex displays antiferromagnetic exchange.
  • Crystal structure and magnetic properties of manganese(II) mellitate, [Mn-2{C-6(COO)(6)}(H2O)(6)][Mn(H2O)(6)]center dot 2H(2)O with two-dimensional layered structure and three-dimensional hydrogen bonding networks, LP Wu, M Yamamoto, T KurodaSowa, M Maekawa, J Fukui, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 239(1-2), 165 - 169, Nov. 1995
    Summary:The crystal and molecular structure of manganese(II) mellitate, [Mn-2{C-6(COO)(6)}(H2O)(6)][Mn(H2O)(6)]. 2H(2)O, has been determined by X-ray structure analysis, The complex crystallizes in the monoclinic system, space group C2/c, with cell constants a = 23.298(3), b = 6.456(3), c = 17.072(2) Angstrom, beta = 101.01(1)degrees and Z = 4. The structure was solved and refined to R = 0.029 (R(w) = 0.036). There are two types of manganese ions in the structure. Mn(1) is situated on a crystallographic center of symmetry and bound to six water molecules while Mn(2) is coordinated octahedrally by three water molecules and three carboxylate oxygen atoms. The major structure feature is that the polyanion formed by Mn(2) ions and the mellitate hexanions with composition of [Mn-2{C-6(COO)(6)}(H2O)(6)](2n-)(n) possesses a two-dimensional layered structure which is linked through a complex three-dimensional hydrogen bonding associated with the Mn(1) cation [Mn(H2O)(6)](2+) and the water of crystallization. Analysis of variable-temperature magnetic susceptibility data (5.0-300 K) shows that the complex displays antiferromagnetic exchange.
  • SYNTHESIS AND CRYSTAL-STRUCTURE OF UNSYMMETRICAL TRINUCLEAR NICKEL(0) COMPLEXES WITH THE 1,3-BUTADIYNES IN THE MONODENTATE AND MU(2)-ETA(2),ETA(2)-BRIDGING MODE [NI-3(L)(COD)(3)] (L=TMSB AND DPBD), M MAEKAWA, M MUNAKATA, T KURODASOWA, K HACHIYA, POLYHEDRON, POLYHEDRON, 14(20-21), 2879 - 2885, Sep. 1995 , Refereed
    Summary:Novel trinuclear nickel(0) complexes [Ni-3(L)(cod)(3)] (cod = 1,5-cyclooctadiene) with L = 1,4-bis(trimethylsilyl)-1,3-butadiyne (1) and 1,4-diphenyl-1,3-butadiyne (2) have been prepared and their structures have been crystallographically determined. These trinuclear nickel(0) complexes are the first unsymmetrical trinuclear complexes with the 1,3-butadiynes in the monodentate and mu(2)-eta(2),eta(2)-coordination mode. The acetylenic C-C distance of 1.343(7) and 1.33(2) Angstrom for 1 and 2 in the mu(2)-eta(2),eta(2)-bridging mode is rather larger than that of 1.267(7) and 1.26(2) Angstrom for 1 and 2 in the monodentate mode, indicative of a larger contribution of pi back donation. The weak nu(C=C) frequency was given at 1784 and 1782 cm(-1) for 1 and 2, respectively.
  • SYNTHESIS AND CRYSTAL-STRUCTURE OF A TRINUCLEAR NICKEL(0) COMPLEX WITH 1,4-BIS(TRIMETHYLSILYL)-1,3-BUTADIYNE IN THE MONODENTATE AND MU(2)-ETA(2),ETA(2)-BRIDGING MODE - [NI-3(TMSB)(COD)(3)], M MAEKAWA, M MUNAKATA, T KURODASOWA, K HACHIYA, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 236(1-2), 181 - 184, Aug. 1995 , Refereed
    Summary:A novel trinuclear nickel (0) complex [Ni-3(tmsb)(cod)(3)] (cod = 1,5-cyclooctadiene) with 1,4-bic(trimethylsilyl)-1,3-butadiyne (tmsb) in the monodentate and mu(2)-eta(2),eta(2)-bridging modes has been prepared and characterized crystallographically. The complex is triclinic, P $($) over bar$$ 1, a = 11.947(2), b = 15.407(3), c = 10.213(2) Angstrom, alpha = 96.47(2), beta = 102.32(2), gamma = 107.05(1)degrees, V = 1724.7(6) Angstrom(3), Z = 2, R = 0.046 and R(w) = 0.052. The acetylenic C-C distance of 1.343(7) Angstrom in the mu(2)-eta(2),eta(2)-bridging mode is considerably larger than that (1.267(7) Angstrom) in the monodentate mode. A weak nu (C=C) frequency was found at 1784 cm(-1).
  • CLEAVAGE OF THE CENTRAL C-C BOND OF 1,4-DIPHENYL-1,3-BUTADIYNE - SYNTHESIS AND CRYSTAL-STRUCTURE OF A TRIANGULAR TRINICKEL COMPLEX BICAPPED BY PHENYLACETYLIDE [NI-3(MU-DPPM)(3)(MU(3)-ETA(1)-C-CPH)(2)], M MAEKAWA, M MUNAKATA, T KURODASOWA, K HACHIYA, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 233(1-2), 1 - 4, May 1995 , Refereed
    Summary:The cleavage of the central C-C bond of 1,4-diphenyl-1,3-butadiyne (dpbd) was caused by the reaction of [Ni(cod)(2)](cod=1,5-cyclooctadiene), dpbd and bis(diphenylphosphino)methane (dppm) to form the triangular trinickel complex [Ni-3(mu-dppm)(3) (mu(3)-eta(1)-C=CPh)(2)] (2) bicapped by two resulting phenylacetylides. We have determined the crystal structure and properties of complex 2. The complex is monoclinic, P2(1)/m, a = 14.227(6), b = 21.651(5), c = 14.497(2) Angstrom, beta = 97.76(3)degrees, V = 4425(2) Angstrom(3), Z=2,R=0.079 and R(W)=0.116. The C=C frequency of the coordinating acetylide was observed at 1933 cm(-1).
  • BUILDING OF 2D SHEET OF TETRAKIS(METHYLTHIO)TETRATHIAFULVALENES COORDINATING TO COPPER(I) HALIDES WITH ZIGZAG AND HELICAL FRAMES AND THE 3D NETWORK THROUGH THE S-CENTER-DOT-CENTER-DOT-CENTER-DOT-S CONTACTS, M MUNAKATA, T KURODASOWA, M MAEKAWA, A HIROTA, S KITAGAWA, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 34(10), 2705 - 2710, May 1995 , Refereed
    Summary:Three copper (I) complexes with tetrakis(methylthio)tetrathiafulvalene (TMT-TTF), [(Cu-2(mu-X)(2)(mu-TMT-TTF)](infinity) (X = Cl, 1; X = Br, 2; and X = I, 3) were synthesized and their molecular structures and packing were determined by using single crystal X-ray diffraction methods. 1 is 2D sheet composed of TMT-TTF molecules arranged between new zigzag frames of CuCl and 3D structure is formed through S ... S contacts of 3.53 and 3.63 Angstrom between the 2D sheets. 2 has a 2D structure in which TMT-TTF molecules are connected between novel helical frames of CuBr and the S ... S contacts of 3.68 Angstrom exist between the neighboring molecules. The methyl thioether groups of TMT-TTF in 3 are coordinated to the coppers of rhomboid Cu2I2 to give linear chains. The black I-2-doped compounds 1-3 show a new broad band at ca 880 nm indicative of the oxidation of TMT-TTF molecules and gave electric conductivities of 10(-3.6), 10(-2.1), and 10(-1.7) S cm(-1), respectively. Crystal data: 1, monoclinic P2(1)/n, a = 6.657(8) Angstrom, b = 6.23(1) Angstrom, c = 24.067(8) Angstrom, beta = 91.77(7)degrees, V = 998(2) Angstrom(3), Z = 4, 1913 reflections, R = 0.028; 2, monoclinic C2/c; a = 15.443(3) Angstrom, b = 4.906(4) Angstrom, c = 26.686(1) Angstrom, beta = 96.36(1)degrees, V = 2009(2) Angstrom(3), Z = 8, 1304 reflections, R = 0.037; 3, monoclinic C2/m, a = 7.921(3) Angstrom, b = 13.266(6) Angstrom, c = 10.498(6) Angstrom, beta = 107.79(4)degrees, V = 1052(2) Angstrom(3), Z = 8, 1072 reflections, R = 0.027.
  • SYNTHESIS AND CRYSTAL-STRUCTURE OF A MONONICKEL(0) AND DINICKEL(0) ETHYLENE COMPLEX WITH 4,4'-BIPYRIDINE - [NI(4,4'-BPY)(C2H4)(2)](2)[NI-2(4,4'-BPY)(C2H4)(4)], M MAEKAWA, M MUNAKATA, T KURODASOWA, K HACHIYA, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 232(1-2), 231 - 234, Apr. 1995 , Refereed
    Summary:A novel nickel(0) ethylene complex [Ni(4,4'-bpy)(C2H4)(2)](2)[Ni-2(4,4'-bpy)(C2H4)(4) (1) (4,4'-bpy = 4,4'-bipyridine) which includes two species of mono- and dinuclear nickel(0) ethylene complex in a unit cell has been prepared and characterized crystallographically. Complex 1 is triclinic, space group P (1) over bar, a = 10.543(4), b = 12.546(4), c = 9.190(4) Angstrom, alpha = 109.64(3), beta = 98.57(4), gamma = 90.98(3)degrees, V = 1129.1(8) Angstrom(3), Z = 1, R = 0.037 and R(w) = 0.039. Each of three nickel atoms provide the trigonal geometry due to the coordination of the nitrogen atom of 4,4'-bpy and two ethylene molecules. Elongation of the C=C distance by similar to 0.03 Angstrom is smaller than that of the usual three-coordinate nickel(0) complexes with alkenes, suggesting that the contribution of pi back-donation is considerably weaker.
  • SYNTHESIS AND CRYSTAL-STRUCTURE OF TETRANUCLEAR NICKEL(0) COMPLEX WITH 1,4-DIPHENYLBUTADIYNE IN THE ETA(2),ETA(2)-BRIDGING MODE, M MAEKAWA, M MUNAKATA, T KURODASOWA, K HACHIYA, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 231(1-2), 213 - 216, Mar. 1995 , Refereed
    Summary:A novel tetranuclear nickel(0) complex [Ni-4(dpbd)(cod)4] (cod=1,5-cyclooctadiene) with 1,4-diphenylbutadiyne (dpbd) ln the eta(2),eta(2)-bridging mode has been prepared and then characterized crystallographically. Two nickel atoms are bridged by every C drop C bond of dpbd in the eta(2),eta(2)-bridging mode to give the tetranuclear structure. Each of four nickel atoms is also bonded to two C=C bonds of cod, providing a distorted tetrahedral geometry. The acetylenic C-C distance of the bridging dpbd is 1.35(1) Angstrom. The elongation of the C drop C distance indicates the contribution of the large pi back donation from nickel to dpbd. It was also found that the acetylenic C-C distances of the Ni(0) diyne complexes in the eta(2),eta(2)-bridging mode are longer than those in the monodentate mode.
  • CRYSTAL-STRUCTURE OF BIS(DIETHYLDITHIOCARBAMATO)PALLADIUM(II) BENZENE SOLVATE, [PD(ET(2)DTC)(2)]CENTER-DOT(C6H6), M MAEKAWA, M MUNAKATA, T KURODASOWA, M MOTOKAWA, ANALYTICAL SCIENCES, ANALYTICAL SCIENCES, 10(6), 977 - 978, Dec. 1994 , Refereed
  • CRYSTAL-STRUCTURE OF TETRAKIS(PYRIDINE)COPPER(II) NITRATE PYRIDINE SOLVATE, [CU(PY)4](NO3)2.2PY, M MAEKAWA, M MUNAKATA, S KITAGAWA, M NAKAMURA, ANALYTICAL SCIENCES, ANALYTICAL SCIENCES, 7(5), 827 - 828, Oct. 1991 , Refereed
  • Crystal Structure and Band-Gap Engineering of a Semiconducting Coordination Polymer Consisting of Copper(I) Bromide and a Bridging Acceptor Ligand, Takashi Okubo, Kento Himoto, Koki Tanishima, Sanshiro Fukuda, Yusuke Noda, Masanobu Nakayama, Kunihisa Sugimoto, Masahiko Maekawa, Takayoshi Kuroda-Sowa, Inorganic Chemistry, Inorganic Chemistry, 57(5), 2373 - 2376, Mar. 05 2018 , Refereed
    Summary:A new semiconducting 3D coordination polymer, [Cu2Br2(ttz)]n (1), with an acceptor bridging ligand, 1,2,4,5-tetrazine (ttz), was synthesized. The complex shows large absorption bands extending to the near-IR region, indicating a small band gap in the coordination polymer. This complex shows higher conductivity than those of [CuBr(pyz)]n (2), including pyrazine (pyz) with a higher lowest unoccupied molecular orbital level. We performed density functional theory band calculations using the VASP program to understand the electronic states and conducting paths of the coordination polymer.
  • A new semiconducting coordination polymer consisting of copper(I)-iodide and 3-pyridinecarboxaldehyde, Kento Himoto, Toshiya Horii, Takumi Syoji, Takashi Okubo, Masahiko Maekawa, Takayoshi Kuroda-Sowa, Inorganic Chemistry Communications, Inorganic Chemistry Communications, 88, 34 - 37, Feb. 01 2018 , Refereed
    Summary:A new one-dimensional coordination polymer, [CuII(3-Py-CHO)]n (3-Py-CHO = 3-pyridinecarboxaldehyde), consisting of an infinite copper(I)-iodide ladder chain and a pendant ligand, 3-Py-CHO, was prepared and structurally characterized using X-ray diffraction analysis. This material shows semiconducting properties with a relatively small activation energy, as shown by impedance measurements. We also estimated the electrical conductivity from a current-voltage (I-V) curve measured from a single crystal of the coordination polymer.
  • Crystal structure of a new mixed-metal coordination polymer consisting of NiII piperidine-dithiocarbamate and pentanuclear CuI-I cluster units, Kento Himoto, Toshiya Horii, Shoki Oda, Shimpei Suzuki, Kunihisa Sugimoto, Takashi Okubo, Masahiko Maekawa, Takayoshi Kuroda-Sowa, Acta Crystallographica Section E: Crystallographic Communications, Acta Crystallographica Section E: Crystallographic Communications, 74, 233 - 236, Feb. 01 2018 , Refereed
    Summary:A new heterometallic CuI-NiII coordination polymer, poly[[tetra-3-iodido-2-iodido-bis(3-piperidine-1-dithiocarbamato)propionitrilepentacopper(I)nickel(II)] chloroform monosolvate], {[CuI 5NiIII5(C6H10NS2)2(C3H5N)]CHCl3}n, has been synthesized and structurally characterized. This coordination polymer consists of an NiII mononuclear unit of NiII(Pip-dtc)2 (Pip-dtc is piperidine-1-dithiocarbamate) and a pentanuclear copper(I) cluster unit of Cu5I5(CH3CH2CN). The NiII ion, which lies on an inversion centre, is surrounded by four S atoms in a square-planar coordination geometry while all CuI ions have distorted tetrahedral coordination geometries. In the pentanuclear copper(I) cluster unit, a mirror plane passes through one CuI ion and three I ions. All the S atoms in NiII(Pip-dtc) are also coordinated by the CuI ions, forming an infinite zigzag chain structure along the b-axis direction. The chains are weakly connected by solvent CHCl3 molecules via Cl I [3.653 (1) Å] and Cl S [3.4370 (1) Å] short-contact interactions.
  • Controlled Self-Assembly of a 2-D Sheet Coordination Polymer and Monomer Containing an Eight-Membered Cu4I4 Crown Motif, Kunihisa Sugimoto, Hikaru Takaya, Masahiko Maekawa, Takayoshi Kuroda-Sowa, Crystal Growth and Design, Crystal Growth and Design, 18(2), 571 - 575, 2018 , Refereed
    Summary:The reaction of Ni(mnt)2 (mnt = 1,2-dicyano-1,2-ethylenedithiolate) with CuI in THF results in the formation of a Ni(mnt)2Cu4I4 unit with an eight-membered Cu4I4 crown motif. Coordination polymers with Ni(mnt)2Cu4I4 building units, having doubly bridged 1-D chains, were formed with bulky NBu4 counterions. To pack the bulky NBu4 cations into the crystal structure, no direct interactions between the 1-D chain structures are observed. When the bulky NBu4 cations are exchanged for small sodium cations, direct interactions between the 1-D chain structures dominate. A doubly bridged 2-D sheet structure is formed through the bridging of the cyano groups of the Ni(mnt)2Cu4I4 units of neighboring 1-D chain structures by sodium atoms. The monomeric [Na2(18-crown-16)]2[Ni(mnt)2Cu4I4] complex is formed when the sodium cations of the 2-D sheet structure are captured by 18-crown-6. The configuration of the coordination polymer or the monomer is controlled through the selection of the appropriate countercation to the Ni(mnt)2Cu4I4 building unit. Furthermore, the eight-membered Cu4I4 crown motifs in the 2-D sheet structure captures sodium cations. In this regard, we propose that the flexible Cu4I4 crown motif is capable of capturing atoms or molecules of various sizes such a material may act as a useful molecular adsorbent through electrostatic interactions.
  • A new semiconducting 1D Cu(i)-Cu(II) mixed-valence coordination polymer with Cu(II) dimethylpiperidine-dithiocarbamate and a tetranuclear Cu(i)-Br cluster unit, K. Himoto, S. Suzuki, T. Okubo, M. Maekawa, T. Kuroda-Sowa, New Journal of Chemistry, New Journal of Chemistry, 42(6), 3995 - 3998, 2018 , Refereed
    Summary:A novel mixed-valence coordination polymer [CuI4CuIIBr4(dmpip-dtc)2(CH3CN)]n (dmpip-dtc = dimethylpiperidine-dithiocarbamate) with an infinite one-dimensional structure was synthesized and structurally characterized using X-ray diffraction. The electronic properties of the coordination polymer were investigated by UV-vis-NIR spectroscopy. Impedance measurement results demonstrated that this complex has a narrow bandgap, inducing semiconducting behavior.
  • Variety of spin transition temperatures of iron(II) spin crossover complexes with halogen substituted Schiff-base ligands, Hqsal(X) (X = F, Cl, Br, and I), Takayoshi Kuroda-Sowa, Rina Isobe, Norifumi Yamao, Tomohiro Fukumasu, Takashi Okubo, Masahiko Maekawa, POLYHEDRON, POLYHEDRON, 136, 74 - 78, Nov. 2017 , Refereed
    Summary:The preparation and magnetic properties of four Fe(11) Schiff-base complexes, [Fe(qsal(x))(2)] (Hqsal(x) = N-(8'-quinoly1)-2-hydroxy-5-halogeno-l-salicylaldimine; X = F(1), C1(2), Br(3), 1(4)) are reported. X-ray single crystal structure analyses of 1 and 2 reveal that Fe(II) ions in both complexes are coordinated by two qsalx ligands in meridional fashion. Molecular packing of 1 shows that a non-planar qsal(F) ligand interacts with neighboring two qsal(F) ligand's through pi-pi interactions, while that of 2 shows that two planar qsal(cl) ligands interact each other through pi-pi interaction. Although the magnetic property of 1 shows a high spin state at all the temperature range measured, the chi T-T plots of 2, 3, and 4 show gradual spin crossover behaviors with T1/2 of 308 K, 341 K, and 340 K, respectively. (C) 2017 Elsevier Ltd. All rights reserved.
  • Structural diversity of copper(I) cyclodiene complexes bridged by 3,6-bis (2-pyridyl)-1,2,4,5-tetrazine, Masahiko Maekawa, Kunihisa Sugimoto, Takashi Okubo, Takayoshi Kuroda-Sowa, Megumu Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 467, 204 - 211, Oct. 2017 , Refereed
    Summary:The reactions of CuX2 center dot nH(2)O (X = ClO4, BF4), Cu turnings and 3,6-bis(2-pyridyl)-1,2,4,5-tetrazine (bptz) with excess 1,5-cyclooctadiene (cod) in Me2CO under C2H4 afforded dinuclear Cu(I)-bptz/eta(2), eta(2)-cod-X complexes {(1) and (4)} and dinuclear Cu(I)-2,5-H(2)bptz/eta(2), eta(2)-cod-X complexes {(2) and (5)}. In complexes 1 and 4, each Cu(I) atom is coordinated by two chelate N atoms of bptz and two C=C bonds of eta(2), eta(2)-cod in the distorted tetrahedral geometry to produce a transoid dinuclear structure. It should be noted that the redox state of the central tetrazine ring is electrochemically neutral. In complexes 2 and 5, each Cu(I) atom is coordinated by two chelate N atoms of 2,5-H(2)bptz and two C=C bonds of eta(2), eta(2)-cod in the distorted tetrahedral geometry to afford a transoid dinuclear structure in the 2,5-dihydro form. In contrast, the reactions of Cu(BF4)(2)center dot nH(2)O, Cu turnings and bptz with excess 2,5-norbornadiene (nbd) in MeEtCO under C2H4 afforded Cu(I)-2,5-H(2)bptz/eta(2)-nbd-BF4 complex (6). Each Cu(I) atom is coordinated by two chelate N atoms in bptz and one C=C bond in eta(2)-nbd to form a transoid dinuclear structure in the 2,5-dihydro form. These facts show that the flexible cod can preferentially produce a Cu(I)cyclodiene complex in the eta(2), eta(2)-mode (complexes 1, 2, 4 and 5) while the rigid nbd can produce a Cu (I)-cyclodiene complex in the eta(2)-mode (complex 6). Furthermore, the reaction of Cu(NO3) center dot 3H(2)O, Cu turnings and bptz with excess nbd in Me2CO under C2H4 afforded tetranuclear Cu(I)-4,5-H(2)bptz-NO3 complex (7) containing a unique anionic [Cu-2(nbd)(NO3)(4)](2) moiety. In the cationic [Cu-4(4,5H(2)bptz) 4] 4+ moiety, four Cu(I) atoms are bridged by four 4,5-H(2)bptz ligands to form a [4 x 4] grid-like tetranuclear structure with two 4,5-H(2)bptz ligands lying above the Cu4 mean plane and two lying below. In the anionic [Cu-2(nbd)(NO3)(4)](2) moiety, the two Cu atoms are bridged by one nbd ligand in the mu(2)-eta(2), eta(2)-mode. (C) 2017 Elsevier B. V. All rights reserved.
  • Structurally Diverse Polynuclear Copper(I) Complexes Bridged by Pyrimidine-, Pyrazine-, and Triazine-based Ligands with Several 2-Pyridyl Groups, Masahiko Maekawa, Kunihisa Sugimoto, Takashi Okubo, Takayoshi Kuroda-Sowa, Megumu Munakata, CHEMISTRYSELECT, CHEMISTRYSELECT, 1(13), 3812 - 3822, Aug. 2016 , Refereed
    Summary:The reactions of [Cu(MeCN)(4)]BF4 or [Cu(C2H4)(n)]ClO4 complexes with 4,6-bis(2-pyridyl)pyrimidine (bppym) in Me2CO under C2H4 afforded dinuclear Cu(I)-bppym/C2H4 adducts [Cu-2-(bppym)(C2H4)2](BF4)(2)center dot Me2CO (1) and [Cu-2(bppym)(2)(C2H4)(2)](ClO4)(2)center dot Me2CO (2), respectively. One Cu(I) atom is coordinated by bppym and C2H4 in a distorted trigonal-planar geometry. The other Cu(I) atom is coordinated by bppym, Me2CO, and C2H4 toward a distorted tetrahedral geometry. The reaction of [Cu(MeCN)(4)]BF4 with 2,3-bis(2-pyridyl)pyrazine (bppz) in MeOH under C2H4 afforded a Cu(I)-bppz coordination polymer {[Cu-2(bppz)(2)](BF4)(2)center dot MeOH} n (3). Two Cu(I) atoms are alternately bridged by two bppz to form a 1-D zigzag-chain structure. Each Cu(I) coordination sphere is largely distorted from a normal tetrahedral structure toward a square planar structure. The reaction of [Cu(MeCN)(4)]PF6 with 2,4,6-tris(2-pyridyl)-s-triazine (tptz) in MeEtCO under C2H4 afforded a tetranuclear Cu(I)-tptz/C2H4 adduct [Cu-4(tptz)(2)(C2H4)(2)(MeCN)(2)](PF6)(4)center dot MeEtCO (4b). Two Cu(I) atoms are bridged by the central triazine ring, the 2-pyridyl group, the central triazine ring, and the 2-pyridyl group in a different tptz to form a double helical structure. The other Cu(I) atom is coordinated by the central triazine ring, the 2-pyridyl group, MeCN, and C2H4 in a distorted tetrahedral geometry. The reaction of [Cu(MeCN)(4)]PF6 with tetra-2-pyridylpyrazine (tppz) in MeOH under C2H4 afforded a tetranuclear Cu(I)-tppz complex [Cu-4(tppz)(2)(MeCN)(4)](PF6)(4)center dot MeOH (5a). Each Cu(I) atom is coordinated by the central pyrazine ring, the 2-pyridyl group, the 2-pyridyl group in a different tppz, and MeCN in a distorted tetrahedral geometry. These four Cu(I) atoms are bridged by the two opposite tppz ligands to form a unique tetranuclear Cu(I) cage structure.
  • Heterometallic Ag-I-Ir-III Hydride Coordination Polymers Bridged by Ir-III Metalloligands, Masahiko Maekawa, Yukimi Kubo, Kunihisa Sugimoto, Takashi Okubo, Takayoshi Kuroda-Sowa, Megumu Munakata, EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, (1), 78 - 91, Jan. 2016 , Refereed
    Summary:A new type of Ir-III metalloligands containing an unsaturated nitrogen coordination site, [Ir(H)(2)(PPh3)(2)(pprd)]BF(4)2CHCl(3) (1), [Ir(H)(2)(PPh3)(2)(Me(2)bpm)]BF4CHCl3 (2), {[Ir(H)(2)(PPh3)(2)(Me(2)bpm)]PF6CHCl3}(4) (3), [Ir(H)(2)(PPh3)(2)(biqz)]BF(4)2CHCl(3) (4), and [Ir(H)(2)(PPh3)(2)(biqz)]PF6 (5), have been prepared by reaction of [Ir(H)(2)(PPh3)(2)(Me2CO)(2)]X (X = BF4 or PF6) with 4-(2-pyridyl)pyrimidine (pprd), 6,6-dimethyl-4,4-bipyrimidine (Me(2)bpm), or 4,4-biquinazoline (biqz). Subsequently, three novel heterometallic Ag-I-Ir-III hydride coordination polymers, {[Ir(H)(2)(-pprd)(PPh3)(2)Ag(-CF3COO)]BF4Me2CO}(n) (6), {[Ir(H)(2)(-biqz)(PPh3)(2)Ag-2(-CF3COO)(3)]Me2CO}(n) (7), and {[Ir(H)(2)(-Me(2)bpm)(PPh3)(2)Ag-2(-CF3COO)(2)]PF(6)2Me(2)CO}(n) (8) have been constructed by reaction of the Ir-III metalloligands 1, 3, and 5 with AgCF3COO. In coordination polymer 6, the [Ir(H)(2)(PPh3)(2)(pprd)](3+) units are linked through the Ag-I atoms to form a 1D zigzag chain structure. In coordination polymer 7, the dinuclear [Ag-2(-CF3COO)(3)](-) units are linked through the terminal N atoms of biqz in two different [Ir(H)(2)(PPh3)(2)(biqz)](3+) units to form a 1D zigzag chain structure. In coordination polymer 8, the [Ag-2(-CF3COO)(2)] frameworks are linked through the terminal N atoms of Me(2)bpm and the Ir-III atom in two different [Ir(H)(2)(PPh3)(2)(Me(2)bpm)](3+) units to form a waved rectangular cavity. These waved rectangular cavities are connected to each other to afford a unique 2D sheet structure.
  • Dinuclear and polymeric copper(I) ethylene adducts bridged by bis-pyridyl derivatives of 1,2,4-triazole and 1,2,4,5-tetrazine, Masahiko Maekawa, Kunihisa Sugimoto, Takashi Okubo, Takayoshi Kuroda-Sowa, Megumu Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 426, 64 - 70, Feb. 2015 , Refereed
    Summary:The reaction of [Cu(MeCN)(4)]PF6 with 3,5-bis(2-pyridyl)-1H-1,2,4-triazole (Hbptrz) in MeOH under C2H4 afforded the colorless needle crystals of [Cu-2(bptrz)(C2H4)(2)]PF6 center dot MeOH (1). The X-ray crystallographic study showed that there are two [Cu-2(bptrz)(C2H4)(2)](+) cation moieties, two PF6 anions and two solvated MeOH molecules in the unit cell. This result indicates that the central triazole ring was deprotonated to produce the anionic bptrz ligand. Each Cu(I) atom is coordinated by two chelate N atoms of bptrz and the C=C bond of C2H4 in the trigonal-planar geometry to produce a notable dinuclear Cu(I)-bptrz/C2H4 adduct bearing the anionic bptrz in the transoid conformation. In contrast, the reaction of Cu(NO3)(2)center dot H2O, Cu turnings and 3,6-bis(4-pyridyl)-1,2,4,5-tetrazine (4-bptz) in Me2CO under C2H4 gave black brick crystals of {[Cu-4(4,5-H-2-4-bptz)(2)(C2H4)(2)(NO3)(4)]center dot Me2CO center dot 0.5H(2)O}(n) (2). This result indicates that 3,6-bis(4-pyridyl)-4,5-dihydro-1,2,4,5-tetrazine (4,5-H-2-4-bptz) was produced by the two-electron reduction of 4-bptz. Four Cu(I) atoms are bridged by two 4,5-H-2-4-bptz and four NO3 anions to form two distinct rectangular [Cu-4(4,5-H-2-4-bptz)(2)(NO3) 4] frameworks. Furthermore, these rectangular [Cu-4(4,5-H-2-4-bptz)(2)(NO3)(4)] subunits are linked via the N atom in the central 4,5-dihydrotetrazine ring each other to generate a unique 2-D Cu(I)-4,5-H-2-4-bptz/C2H4-NO3 coordination polymer with a channel structure along the a-axis. Thermogravimetric analysis (TG-DTA) showed that complexes 1 and 2 were thermochemically stable to a relatively high temperature. (C) 2014 Elsevier B.V. All rights reserved.
  • The first copper(I) coordination polymers self-assembled by 4,4 '-biquinazoline, Masahiko Maekawa, Ai Minamino, Kunihisa Sugimoto, Takashi Okubo, Takayoshi Kuroda-Sowa, Megumu Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 414, 257 - 263, Apr. 2014 , Refereed
    Summary:The reactions of [Cu(MeCN)(4)](X) (X = BF4 or PF6) with 4,4'-biquinazoline (biqz) in MeOH under C2H4 afforded brown plate crystals of {[Cu-4(biqz)(2)(MeCN)(4)(MeOH)(4)](BF4)(4)}(n) (1) and orange prismatic crystals of {[Cu-4(biqz)(2)(MeCN)(8)](PF6)(4)}(n) (2), respectively. In both of complexes 1 and 2, two Cu(I) atoms are bridged by two biqz ligands to form a 14-membered Cu4C6N4 framework. Furthermore, the Cu4C6N4 frameworks are linked by the two chelate and bridging sites of biqz to generate a 1-D double-chain Cu(I) coordination polymer. It should be noted that two N atoms in the chelate site of the biqz ligand does not act as a normal bidentate chelate mode but form a bridge between two Cu atoms in an unidentate bridging mode. In contrast, the reaction of [Cu(C2H4)(n)]ClO4 with biqz in Me2CO under C2H4 afforded orange plate crystals of polymeric Cu(I)-biqz/C2H4 adduct {[Cu-2(biqz)(C2H4)(2)](ClO4)(2)center dot Me2CO}(n) (3). The Cu atom is coordinated by two N atoms of biqz in the chelate site and the C=C bond of C2H4 in a rather distorted trigonal-planar geometry. The other Cu atom is coordinated by two N atom of two biqz ligands in the exo bridging site and the C=C bond of C2H4 in a trigonal-planar geometry to form a 1-D zigzag-chain structure. It was proved that the Cu(I) coordination polymers bridged by the biqz ligand in the different coordination modes can be preferentially produced by the choices of the precursor Cu(I) complexes. The thermogravimetric analysis (TG-DTA) measurements showed that Cu(I)-biqz-{BF4, PF6} complexes 1 and 2 were thermochemically stable to a relatively high temperature (330-340 degrees C). (C) 2014 Elsevier B. V. All rights reserved.
  • Crystal Structure and Characterization of Trinuclear Cobalt(III) Complex with 2,3,6,7,10,11-Hexahydroxytriphenylene, Yusaku Suenaga, Honami Inada, Masataka Inomata, Ryotaro Yamaguchi, Takashi Okubo, Masahiko Maekawa, Takayoshi Kuroda-Sowa, CHEMISTRY LETTERS, CHEMISTRY LETTERS, 43(4), 562 - 564, Apr. 2014 , Refereed
    Summary:Trinuclear Co(III) complex [Co-3(III)(tpa)(3)(L)](BF4)(4) (tpa: tris-(2-pyridylmethyl)amine, H6L: 2,3,6,7,10,11-hexahydroxytriphenylene) is prepared from methanol solution. Single-crystal structure analysis revealed that the valency of the three cobalt ions is +3 and that the tris(dioxolene) bridging ligand is formally in the -5 [cat,cat,sq] oxidation state. This complex is stable in the entire temperature range investigated. Various-temperature magnetic susceptibility data for the compound displayed little variation in the range 2-300K, and the reason caused the distinct charge distribution on Co-L (L: bridging ligand) by the natural rigidity of the tripodal ligands. Also, its CH3CN solution exhibits a very strong NIR absorption arising from an internal ligand transition within the triphenylene ligand. Cyclic voltammetry (CV) measurements in CH3CN solution show three reversible cat sq redox waves for the triphenylene ligand.
  • New one-dimensional mixed-valence coordination polymers including an iodine-bridged pentanuclear copper(I) cluster unit, Takashi Okubo, Haruho Anma, Yuuki Nakahashi, Masahiko Maekawa, Takayoshi Kuroda-Sowa, POLYHEDRON, POLYHEDRON, 69, 103 - 109, Feb. 2014 , Refereed
    Summary:New mixed-valence coordination polymers {[(Cu5CuI5L2)-Cu-I-I-II(C2H5CN)(2)]center dot CHCl3)(n) (L = piperidinedithiocarbamate and hexamethyl-dithiocarbamate) with isomorphous infinite one-dimensional (1D) structures were prepared and structurally characterized via X-ray diffraction. These complexes comprised a mononuclear Cu(II) unit, (CuL2)-L-II, and a pentanuclear Cu(I) cluster unit, (Cu5I5)-I-I(C2H5CN)(2). Impedance measurements demonstrated that these Cu(I)-Cu(II) mixed-valence 1D coordination polymers displayed semiconducting behavior with low conductivities. (C) 2013 Elsevier Ltd. All rights reserved.
  • Preparations and structural diversity of copper(I) ethylene adducts with related 3,6-bis(2-pyridyl)-1,2,4,5-tetrazine ligands, Masahiko Maekawa, Takeshi Miyazaki, Kunihisa Sugimoto, Takashi Okubo, Takayoshi Kuroda-Sowa, Megumu Munakata, Susumu Kitagawa, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 410, 46 - 53, Jan. 2014 , Refereed
    Summary:The reaction of [Cu(C2H4)n]NO3, Cu turnings, 3,6-bis(2-pyridyl)-1,2,4,5-tetrazine (bptz), and ferrocene in Me2CO under C2H4 afforded black crystals of [Cu-4(4,5-H(2)bptz)(4)][Cu(C2H4)(NO3)(2)](2)(NO3)(2)center dot 2Me(2)CO (7). In the [Cu-4(4,5-H(2)bptz)(4)](4+) cation moiety, four Cu(I) atoms are bridged by four 4,5-H(2)bptz ligands to form a [4 x 4] grid-like tetranuclear structure. In the [Cu(C2H4)(NO3)(2)] anion moiety, the Cu atom is coordinated by two NO3 anions in the unidentate coordination mode and by the C=C bond of C2H4 to form a mononuclear Cu(I)-C2H4 adduct in the trigonal-planar geometry. It should be noted that two anionic Cu(I)-C2H4 adducts [Cu(C2H4)(NO3)(2)] are present as a co-crystal. The similar reaction of Cu(BF4)(2)center dot H2O, Cu turnings, bptz, and ferrocene in MeEtCO under C2H4 afforded colorless crystals of [Cu-2(bpdpyz)(C2H4) (2)](BF4)(2) (9). In the [Cu-2(bpdpyz)(C2H4)(2)](2+) cation moiety, each Cu(I) atom is coordinated by two chelate N atoms of bpdpyz and the C=C bond of C2H4 to afford an unusual cisoid dinuclear structure. This result shows that 3,6-bis(2-pyridyl)-4,5-dihydropyridazine (bpdpyz) can be produced by the cycloaddition of bptz with C2H4 via a Diels-Alder addition and retro-Diels-Alder elimination of dinitrogen to form complex 9. In contrast, the reaction of Cu(BF4)(2)center dot H2O, Cu turnings, and bptz in Me2CO in the absence of ferrocene afforded black crystals of [Cu-4(4,5-H(2)bptz)(4)](BF4)(4)center dot Me2CO (12). Although the apparent structure of the [Cu-4(4,5-H(2)bptz)(4)](4+) cation moiety is similar to that of the [Cu-4(4,5-H(2)bptz)(4)](4+) cation moiety in complex 7, the shape of the Cu-4 framework is closer to a square structure, resulting in the adjacency of the two opposite tetrazine rings. The preparations and structural diversity of Cu(I)-C2H4 adducts with the related bptz ligands are described in addition to related previous results. (C) 2013 Elsevier B.V. All rights reserved.
  • Halido-bridged 1D mixed-valence CuI-CuII coordination polymers bearing a piperidine-1-carbodithioato ligand: Crystal structure, magnetic and conductive properties, and application in dye-sensitized solar cells, Naoya Tanaka, Takashi Okubo, Haruho Anma, Kyung Ho Kim, Yoshie Inuzuka, Masahiko Maekawa, Takayoshi Kuroda-Sowa, European Journal of Inorganic Chemistry, European Journal of Inorganic Chemistry, (19), 3384 - 3391, Jul. 2013 , Refereed
    Summary:New mixed-valence CuI-CuII 1D coordination polymers of the structure [CuI 2CuIIX2(Pip- dtc)2(CH3CN)2]n [Pip-dtc = piperidine-1-carbodithioate X = Br (1a), I (1b)] containing a dithiocarbamate derivative have been synthesized and structurally characterized by X-ray diffraction. The 1D infinite chains were formed from mononuclear copper units [Cu(Pip-dtc)2] connected by bromido- or iodido-bridged copper dinuclear units that include acetonitrile ligands {i.e., [Cu2X 2(CH3CN)2]}. Evaluation of the magnetic properties of 1a and 1b revealed that these complexes displayed relatively strong antiferromagnetic interactions [J = -20.4 cm-1 (1a) and J = -18.8 cm-1 (1b)] between unpaired electrons of the copper(II) ions through the dinuclear halido-copper(I) units. Impedance spectroscopy revealed that complexes 1a and 1b exhibit intriguing semiconducting properties at activation energies of Ea = 0.78 eV (1a) and Ea = 0.62 eV (1b). Coordination polymers 1a and 1b were then adopted as the sensitizing material in dye-sensitized solar cells (DSSCs). New halido-bridged mixed-valence CuI-CuII coordination polymers with 1D infinite chain structures have been synthesized and structurally characterized The complexes show a relatively strong antiferromagnetic interaction and interesting semiconducting behavior. These coordination polymers were applied as sensitizing materials for DSSCs. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
  • Air-stable cyclohexasulfur as cocrystal, Kunihisa Sugimoto, Hiroshi Uemachi, Masahiko Maekawa, Akihiko Fujiwara, Crystal Growth and Design, Crystal Growth and Design, 13(2), 433 - 436, Feb. 06 2013 , Refereed
    Summary:A new stable cyclohexasulfur (cyclo-S6) was discovered in the crystal of 3,5-diphenyl-1,2,4-dithiazol-1-ium (dpdti) dpdti was synthesized via an oxidation reaction of thiobenzamide with iodine in benzene, under reflux. Two kinds of crystal habits - brick-shaped (crystal-A) and needle-shaped (crystal-B) - were obtained following recrystallization from acetonitrile solvent. Single-crystal structure analysis using synchrotron X-ray radiation showed that both crystal-A and -B consist of a dpdti cation and an iodine anion. Furthermore, neutral cyclo-S6 molecules are present in crystal-A as cocrystals, enclosed by the dpdti cation and the iodide anion. This is akin to cyclosulfur of Sn in zeolites and sodalities, suggesting a contribution to the stabilization of cyclo-S6 molecules. The results show that crystal engineering of cocrystals may be used as a method to control the stability and activity of sulfur, for improved utilization. © 2012 American Chemical Society.
  • Structural diversity among copper(I) ethylene adducts of 3,6-bis(2-pyridyl)-1,2,4,5-tetrazine, Masahiko Maekawa, Takeshi Miyazaki, Kunihisa Sugimoto, Takashi Okubo, Takayoshi Kuroda-Sowa, Megumu Munakata, Susumu Kitagawa, DALTON TRANSACTIONS, DALTON TRANSACTIONS, 42(12), 4258 - 4266, 2013 , Refereed
    Summary:The reaction of Cu(ClO4)center dot 6H(2)O, Cu turnings, and 3,6-bis(2-pyridyl)-1,2,4,5-tetrazine (bptz) in Me2CO under C2H4 afforded brownish-red needle crystals of {[Cu-2(bptz(center dot-))(C2H4)(2)](ClO4)}(2) (1) as a minor product and brown plate crystals of [Cu-2(2,5-H(2)bptz)(C2H4)(2)](ClO4)(2)center dot 2Me(2)CO (2). The X-ray crystallographic study showed that complex 1 is composed of two independent [Cu-2(bptz(center dot-))(C2H4)(2)](+) cation moieties and two ClO4- anions. In both of the cation moieties, each Cu(I) atom is coordinated by two chelate N atoms of bptz(center dot-) and the C=C bond of C2H4 in the trigonal-planar geometry to form a unique transoid dinuclear Cu(I)-bptz(center dot-)/C2H4 adduct bearing a metal-stabilized tetrazine anion radical, bptz(center dot-), which was produced by the one-electron reduction of bptz. In contrast, complex 2 consists of one [Cu-2(2,5-H(2)bptz)(C2H4)(2)](2+) cation moiety, two ClO4- anions, and two solvated Me2CO molecules. Each Cu(I) atom is coordinated by two chelate N atoms of 2,5-H(2)bptz and the C=C bond of C2H4 in the trigonal-planar geometry to afford a transoid dinuclear Cu(I)-C2H4 adduct with 2,5-H(2)bptz, which was produced by the two-electron reduction of bptz. Additionally, the similar reaction of Cu(ClO4)center dot 6H(2)O, Cu turnings, and bptz in Me2CO or MeEtCO under C2H4 in the presence of ferrocene afforded orange brick crystals of [Cu-2(bpdpyz)(C2H4)(2)]- (ClO4)(2)center dot Me2CO (3) and [Cu-2(bpdpyz)(C2H4)(2)](ClO4)(2) (4), respectively, together with complex 1 in higher yield. This result shows that 3,6-bis(2-pyridyl)-4,5-dihydropyridazine (bpdpyz) was produced by the cyclo-addition of bptz with C2H4 via a Diels-Alder addition and retro-Diels-Alder elimination of dinitrogen. In complexes 3 and 4, each Cu(I) atom is coordinated by two chelate N atoms of bpdpyz and the C=C bond of C2H4 to afford an unusual cisoid dinuclear Cu(I)-C2H4 adduct. Further attempts to react excess [Cu(C2H4)(n)]ClO4 with bptz in Me2CO under C2H4 afforded black brick crystals of [Cu-4(4,5-H(2)bptz)(4)](ClO4)(4)center dot 2Me(2)CO (5) together with complex 1. Complex 5 is the first [4 x 4] grid-like tetranuclear Cu(I) complex constructed by the combination of Cu(I) ion and 4,5-H(2)bptz. The four Cu(I) atoms are spanned by four 4,5-H(2)bptz ligands, with two lying above the Cu-4 mean plane and two lying below. In contrast, the similar reaction of excess [Cu(C2H4)(n)]ClO4 with bptz in Me2CO under C2H4 in the presence of ferrocene afforded reddish-brown brick crystals of {[Cu-2(2,5-H(2)bptz)(C2H4)(2)](ClO4)(2)}(2)center dot Me2CO (6) together with complexes 1 and 5. Complex 6 is composed of two independent [Cu-2(2,5-H(2)bptz)(C2H4)(2)](2+) cation moieties, four ClO4- anions, and a solvated Me2CO molecule. It is interesting that the structures of the two [Cu-2(2,5-H(2)bptz)(C2H4)(2)](2+) cation moieties are different: one has a nearly planar structure and the other possesses a boat conformation owing to the bent central dihydrotetrazine ring.
  • Crystal structure and carrier transport properties of a new semiconducting 2D coordination polymer with a 3,5-dimethylpiperidine dithiocarbamate ligand, Takashi Okubo, Haruho Anma, Naoya Tanaka, Kento Himoto, Shu Seki, Akinori Saeki, Masahiko Maekawa, Takayoshi Kuroda-Sowa, CHEMICAL COMMUNICATIONS, CHEMICAL COMMUNICATIONS, 49(39), 4316 - 4318, 2013 , Refereed
    Summary:A novel mixed-valence Cu(I)-Cu(II) coordination polymer with an infinite two-dimensional structure, [(Cu3CuBr3)-Cu-I-Br-II(3,5-Dmpip-dtc)(2)](n) (3,5-Dmpip-dtc(-) = 3,5-dimethylpiperidine dithiocarbamate), was prepared, and its structure was characterized by X-ray diffraction. It shows semiconducting behavior with a relatively small activation energy and high carrier mobility, which were investigated using impedance spectroscopy and flash photolysis time-resolved microwave conductivity measurements, respectively.
  • Dye-sensitized Solar Cells with New One-Dimensional Halide-Bridged Cu(I)-Ni(II) Heterometal Coordination Polymers Containing Hexamethylene Dithiocarbamate Ligand, Takashi Okubo, Naoya Tanaka, Haruho Anma, Kyung Ho Kim, Masahiko Maekawa, Takayoshi Kuroda-Sowa, POLYMERS, POLYMERS, 4(3), 1613 - 1626, Sep. 2012 , Refereed
    Summary:One-dimensional (1D) halide-bridged Cu(I)-Ni(II) heterometal coordination polymers containing a hexamethylene dithiocarbamate (Hm-dtc) ligand have been synthesized and crystallographically characterized. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels of the coordination polymers were estimated using UV-Vis-NIR and photoelectron spectroscopies, and it was revealed that these coordination polymers have appropriate HOMO levels for use as dye sensitizers. Direct-current electrical conductivity measurements and impedance measurements indicated that these 1D Cu(I)-Ni(II) heterometal coordination polymers were insulators (sigma(300K) < 10(-12) S cm(-1)). In addition, the coordination polymers were used as sensitizing materials in dye-sensitized solar cells (DSSCs). DSSCs with 1D Cu(I)-Ni(II) heterometal coordination polymers showed lower performances than those with 1D halide-bridged Cu(I)-Cu(II) mixed-valence coordination polymers.
  • Syntheses, crystal structures, spectroscopic characterization and unusual thermal robustness of mono- and di-nuclear Iridium(III) hydride complexes of 2,2 '-bipyrimidine, Masahiko Maekawa, Yukimi Kubo, Kunihisa Sugimoto, Toshie Minematsu, Takashi Okubo, Takayoshi Kuroda-Sowa, Megumu Munakata, POLYHEDRON, POLYHEDRON, 40(1), 145 - 152, Jun. 2012 , Refereed
    Summary:The reaction of [Ir(H)(2)(PPh3)(2)(Me2CO)(2)]BF4 with 2,2'-bipyimidine (bpym) in CHCl3 afforded the yellow needle crystals of mononuclear Ir(III)-bpym/hydride complex [Ir(H)(2)(PPh3)(2)(bpym)]BF4 center dot 4CHCl(3) (1). In contrast, when CH2Cl2 or CHCl3 solution of [Ir(H)(2)(PPh3)(2)(Me2CO)(2)]BF4 were layered by the THF solution of bpym, red brick crystals of dinuclear Ir(III)-bpym/hydride complex [Ir-2(H)(4)(PPh3)(4)(bpym)](BF4)(2)center dot 2CH(2)Cl(2)center dot 2THF (2) and orange brick crystals of [Ir-2(H)(4)(PPh3)(4)(bpyrn))(BF4)(2)center dot 2CHCl(3) (3) were solvent-selectively formed. The UV-Vis spectra of complexes 1-3 in the solid state demonstrated that the absorptions of complexes 2 (495 nm) and 3 (510 nm) exhibited a significant red-shift relative to that (420 nm) of complex 1. Complexes 1-3 redissolved in CD2Cl2 gave several well-resolved H-1 NMR signals at 23 degrees C. It is noteworthy that all H-1 NMR signals of the coordinated pyrimidine rings in complexes 1-3 were shifted to the upfield region relative to those of the metal-free bpym ligand, in which the coordination shifts (Delta delta = delta(complex) - delta(metal-free)) are {-0.12 (H-6.6'), -0.73 (H-4.4') and -0.55 (H-5.5') ppm} for complex 1, {-0.81 (H-4.4') and -0.67 (H-5.5') ppm} for complex 2, and {-0.72 (H-4.4') and -0.58 (H-5.5') ppm} for complex 3. It was proved that unusual upheld shifts can be caused by the diamagnetic anisotropic ring current effect between the adjacent bpym and phenyl groups of PPh3. Thermogravimetric analysis (TG-DTA) showed that Ir(III)-bpym/hydride complexes 1-3 were thermochemically stable to a relatively high temperature near 330 degrees C. (C) 2012 Elsevier Ltd. All rights reserved.
  • Structural controls of 2D sheet copper(I) ethylene and carbonyl coordination polymers directed by anions and solvents, Masahiko Maekawa, Toshi Tominaga, Kunihisa Sugimoto, Takashi Okubo, Takayoshi Kuroda-Sowa, Megumu Munakata, Susumu Kitagawa, CRYSTENGCOMM, CRYSTENGCOMM, 14(18), 5955 - 5962, 2012 , Refereed
    Summary:The reactions of Cu(I) ion with {BF4-, ClO4-, or PF6-} anions and 6,6'-dimethyl-4,4'-bipyrimidine (Me(2)bpm) under C2H4 or CO in MeOH preferentially afforded three 2D sheet Cu(I)-Me(2)bpm/{C2H4, CO} adducts [Cu-4(Me(2)bpm)(3)(C2H4)(3)(MeCN)](BF4)(4)center dot 0.33MeOH}(n) (2), {[Cu-4(Me(2)bpm)(3)(C2H4)(3)(MeOH)(0.33)](ClO4)(4)}(n) (3), and {[Cu-4(Me(2)bpm)(3)(CO)(3)(MeCN)](PF6)(4)center dot 0.33MeCN}(n) (4), whereas the similar reaction of Cu(I) ion with a BF4- anion and Me(2)bpm under CO in MeOH gave the metallamacrocyclic tetranuclear Cu(I)-Me(2)bpm/CO adduct [Cu-4(Me(2)bpm)(4)(CO)(4)](BF4)(4)center dot 4MeOH (5). In Cu(I)-Me(2)bpm/{C2H4, CO} adducts 2-4, it should be noted that the metallacalix[3]arene structures of the [Cu-3(Me(2)bpm)(3)](3+) framework are linked through another Cu atom with MeCN (2 and 4) or MeOH (3) to produce a chiral 2D sheet structure with small Cu-3 and large Cu-9 cavities. In the small triangular Cu-3 cavities, one MeOH (2) or MeCN (4) molecule is encapsulated in complexes 2 and 4, whereas these Cu-3 cavities are empty in complex 3. In the large Cu-9 cavities, one anion (X = BF4- (2), ClO4- (3) or PF6- (4)) is surrounding by six Me groups of three Me(2)bpm on the upside and three anions (X) are functionally accommodated on the downside for complexes 2-4, respectively. In the Cu(I)-Me(2)bpm/CO adduct 5, two of the four BF4- anions are accommodated in the upper and lower cavities of the [Cu-4(Me(2)bpm)(4)] framework. We demonstrated that the metallamacrocyclic and polymeric 2D sheet Cu(I)-Me(2)bpm/{C2H4, CO} adducts can be reasonably self-assembled under the direction of anions and solvents.
  • Effects of weak interactions on spin crossover properties of iron(II) complexes with extended pi-conjugated Schiff-base ligands, Takayoshi Kuroda-Sowa, Kana Kimura, Jun Kawasaki, Takashi Okubo, Masahiko Maekawa, POLYHEDRON, POLYHEDRON, 30(18), 3189 - 3192, Nov. 2011 , Refereed
    Summary:The preparation and magnetic properties of two Fe(II) Schiff-base complexes, [Fe(qnal-12)(2)]center dot 2C(6)H(6) (1) and [Fe(Hqsalc)(2)] (2), (Hqnal-12 = N-(8'-quinolyl)-1-hydroxy-2-naphthaldimine, H(2)qsalc = 4-hydroxy-3-[(8-quinolinylimino)methyl][benzoic acid) are reported. X-ray single crystal structure analysis of 1 reveals that an Fe(II) ion is coordinated by two qnal-12 ligands in a meridional fashion. Molecular packing of 1 shows that a qnal-12 interacts with neighboring two qnal-12's through it-it interactions, which results in the formation of one-dimensional chain. Although the magnetic property of 1 shows a high-spin state at all the temperature range measured, the chi T-T plot of 2 shows abrupt spin crossover behavior with a wide hysteresis of 21 K, probably due to the hydrogen-bond network originated by carboxyl groups. (C) 2011 Elsevier Ltd. All rights reserved.
  • Synthesis and Conducting Properties of a New Mixed-valence Cu(I)-Cu(II) 1-D Coordination Polymer Bridged by Morpholine Dithiocarbamate, Kyung Ho Kim, Takashi Ueta, Takashi Okubo, Shinya Hayami, Haruho Anma, Kazuya Kato, Tetsuya Shimizu, Jyunji Fujimori, Masahiko Maekawa, Takayoshi Kuroda-Sowa, CHEMISTRY LETTERS, CHEMISTRY LETTERS, 40(10), 1184 - 1186, Oct. 2011 , Refereed
    Summary:A novel mixed-valence Cu(I)-Cu(II) coordination polymer with an infinite one-dimensional (1-D) structure, [(Cu4CuI4)-Cu-I-I-II(Mor-dtc)(2)(CH3CN)(2)](n) (Mor-dtc(-): morpholine dithiocarbamate), was prepared and structurally characterized by X-ray diffraction. This complex consists of a mononuclear copper(II) unit of [Cu-II(Mor-dtc)(2)] and a tetranuclear Cu(I) unit of [Cu4I4(CH3CN)(2)]. It also shows semiconductive behaviors with a relatively small activation energy, which was revealed by impedance analysis.
  • Intervalence Charge-Transfer System by 1D Assembly of New Mixed-Valence Octanuclear Cu-I/Cu-II/Cu-III Cluster Units, Takashi Okubo, Hiroyasu Kuwamoto, Kyung Ho Kim, Shinya Hayami, Akihito Yamano, Motoo Shiro, Masahiko Maekawa, Takayoshi Kuroda-Sowa, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 50(7), 2708 - 2710, Apr. 2011 , Refereed
    Summary:The reaction of Cu(Hm-dtc)(2), Br-2, and CuBr2 yielded a new mixed-valence octanuclear Cu-I/Cu-II/Cu-III cluster, encapsulating a Br anion in the center of the cluster cage. The octanuclear cluster units form a 1D assemblage, which induces intervalence charge-transfer transitions from Cu-II ions to Cu-III ions between the clusters.
  • Crystal structure and carrier transport properties of a new 3D mixed-valence Cu(I)-Cu(II) coordination polymer including pyrrolidine dithiocarbamate ligand, Takashi Okubo, Naoya Tanaka, Kyung Ho Kim, Haruho Anma, Shu Seki, Akinori Saeki, Masahiko Maekawa, Takayoshi Kuroda-Sowa, DALTON TRANSACTIONS, DALTON TRANSACTIONS, 40(10), 2218 - 2224, 2011 , Refereed
    Summary:A novel mixed-valence Cu(I)-Cu(II) coordination polymer having an infinite three-dimensional (3D) structure, {[(Cu4Cu2Br4)-Cu-I-Br-II(Pyr-dtc)(4)]center dot CHCl3}(n) (1) (Pyr-dtc(-) = pyrrolidine dithiocarbamate), has been prepared and structurally characterized via X-ray diffraction. This complex consists of 1D Cu(I)-Br chains and bridging mononuclear copper(II) units of Cu-II(Pyr-dtc)(2), which form an infinite 3D network. A magnetic study indicates that this complex includes copper(II) ions exhibiting a weak antiferromagnetic interaction (theta = -0.086 K) between the unpaired electrons of the copper(II) ions present in the diamagnetic Cu(I)-Br chains. The carrier transport properties of 1 are investigated using an impedance spectroscopy technique and flash-photolysis time-resolved microwave conductivity measurement (FP-TRMC). The impedance spectroscopy reveals that this complex exhibits intriguing semiconducting properties at a small activation energy (E-a = 0.29 eV (bulk)). The sum of the mobilities of the negative and positive carriers estimated via FP-TRMC is Sigma mu similar to 0.4 cm(2) V-1 s(-1).
  • Novel 1D Cu(I) coordination polymers formed by the combination of Cu(I) halides and 4-(2-pyridyl)pyrimidine, Masahiko Maekawa, Kunihisa Sugimoto, Takashi Okubo, Takayoshi Kuroda-Sowa, Megumu Munakata, POLYHEDRON, POLYHEDRON, 29(14), 2807 - 2813, Sep. 2010 , Refereed
    Summary:Three novel 1D Cu(I) coordination polymers [Cu4X4(pprd)(2)](n) (X = Cl(1), Br(2) and I(3): pprd = 4-(2-pyridyl)pyrimidine) were systematically synthesized by Cu(I) halides and the pprd ligand, and they have been characterized by X-ray, IR, and TG-DTA analyses. The molecular structure of complex 1 essentially resembles to that of complex 2. In complexes 1 and 2, four Cu(I) atoms are bridged by four Cl or Br anions to form an eight-membered Cu4X4 framework in the twist-chair form. Furthermore, the Cu4X4 frameworks are coordinated by the chelate and bridging sites of two pprd ligands to form a unique 1D two-stepped Cu(I) coordination polymer, in which two stairs are formed by the Cu4X4 core and two heteroaromatic planes of pprd. In the crystal packing structures, it is interesting that two heteroaromatic planes of pprd are stacking along the b-axis for complex 1 and the a-axis for complex 2. In contrast, four Cu(I) atoms in complex 3 are bridged by four I atoms to form a Cu4I4 stepped cubane tetramer. Additionally, the Cu4I4 stepped cubane cores are linked by the chelate and bridging sites of two pprd ligands to form an infinite 1D zigzag-chain Cu(l) coordination polymer. The thermal decomposition behaviors for Cu(I)-X/pprd complexes 1, 2 and 3 were determined by thermogravimetric analysis (TG-DTA). Although the thermal decomposition behaviors of complex 1 were unidentified, those of complexes 2 and 3 were assigned. The mass loss at the first stage of thermal decomposition for polymeric [Cu4X4(pprd)(2)](n) was identical to the formation of oligomeric [Cu4X4(pprd)] by the elimination of one pprd molecule. The mass loss at the next stage was decided to the formation of Cu4X4 by the elimination of another pprd molecule. (C) 2010 Elsevier Ltd. All rights reserved.
  • Dye-sensitized Solar Cells with Halide-bridged Mixed-valence Cu(I)-Cu(II) Coordination Polymers with Hexamethylenedithiocarbamate Ligand, Kyung Ho Kim, Takashi Okubo, Naoya Tanaka, Naoto Mimura, Masahiko Maekawa, Takayoshi Kuroda-Sowa, CHEMISTRY LETTERS, CHEMISTRY LETTERS, 39(7), 792 - 793, Jul. 2010 , Refereed
    Summary:The application of halide-bridged mixed-valence Cu(I)Cu(II) coordination polymers with hexamethylenedithiocarbamate (Hm-dtc) ligand as sensitizing materials for dye-sensitized solar cells (DSSCs) with poly(3,4-ethylenedioxythiophene) tetramethacrylate (PEDOT-TMA) counter electrode is novel. DSSCs having coordination polymers in comparison with a mononuclear Cu(Hm-dtc)(2) complex exhibited better power conversion efficiency because of the high photocurrent density.
  • Magnetic and Conducting Properties of New Halide-Bridged Mixed-Valence Cu-I-Cu-II 1D Coordination Polymers Including a Hexamethylene Dithiocarbamate Ligand, Takashi Okubo, Naoya Tanaka, Kyung Ho Kim, Hironobu Yone, Masahiko Maekawa, Takayoshi Kuroda-Sowa, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 49(8), 3700 - 3702, Apr. 2010 , Refereed
    Summary:New mixed-valence Cu-I-Cu-II coordination polymers with one-dimensional, infinite-chain structures, [(Cu2CuX2)-Cu-I-X-II(Hm-dtc)(2)(CH3-CN)(2)](n) [Hm-dtc(-) = hexamethylene dithiocarbamate, X = Br- (1), I- (2)], have been prepared and structurally characterized by X-ray diffraction. These complexes consist of a mononuclear copper(II) unit Cu-II(Hm-dtc)(2) and dinuclear copper(I) units Cu-2(I)(CH3CN)(2)X-2. Magnetic studies have revealed that these complexes have a relatively strong antiferromagnetic interaction [J = -26.9 cm(-1) (1) and J = -22.2 cm(-1) (2)] between the unpaired electrons of the Cu-II ions through the dinuclear copper(I) halide unit of (Cu2X2)-X-I in the chain. The electrical properties of 1 and 2 are investigated using an impedance spectroscopy technique, and it is revealed that these complexes exhibit intriguing semiconducting properties with small activation energies [E-a = 0.562 eV (1) and E-a = 0.479 eV (2)].
  • Columnar Structure Formed by Dimeric Fe-II Schiff Base Complex: Twisted-Overlap Salophen Platforms and Ferromagnetic Interaction, Zhong Yu, Toshiyuki Shimizu, Toshi Tominaga, Takashi Okubo, Masahiko Maekawa, Takayoshi Kuroda-Sowa, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 82(10), 1274 - 1276, Oct. 2009 , Refereed
    Summary:Columnar assembly of dimeric Fell Schiff base complex based on twisted-overlap orientation of salophen platfonns exhibits ferromagnetic interactions at low temperature, which is ascribable to mu-phenoxy-bridged Fe ... Fe interactions and pi-pi interactions.
  • Ferromagnetic interaction in iron(II)-bis-Schiff base complexes, Atsuhiro Nabei, Takayoshi Kuroda-Sowa, Toshiyuki Shimizu, Takashi Okubo, Masahiko Maekawa, Megumu Munakata, POLYHEDRON, POLYHEDRON, 28(9-10), 1734 - 1739, Jun. 2009 , Refereed
    Summary:The preparation and magnetic properties of three Fe(II)-bis-Schiff base complexes, [Fe(2)(L1)2(4,4'-bpy)]center dot MeOH (1), [Fe(L2)(EtOH)] (2) and [Fe(L3)(MeOH)] (3) (L1 =N,N'-bis(2-hydroxy-1-naphthaldehyde)-1,2-phenylenediimine; L2 = N,N'-bis(salicylidene)-1,2-phenylenediamine; L3 = N,N'-bis(5-Cl-salicylidene)-1,2-phenylenediamine; 4,4'-bpy = 4,4'-bipyridine) are reported. X-ray single crystal structure analyses for 1-3 reveal that 1 shows a dinuclear Fe(II)-bis-Schiff base complex bridged by 4,4'-bpy, while 2 and 3 show mononuclear structures. Molecular packing of 2 shows a uniform one-dimensional chain structure through hydrogen bonds and Fe center dot center dot center dot pi interaction and that of 3 indicates significant pi-pi interaction to form a dimmer structure. The chi T-T plots of 1-3 show all ferromagnetic interaction at low temperature. The origin of the ferromagnetic interaction observed in 2 is tentatively ascribed to the dimer formation through Fe center dot center dot center dot pi interaction at low temperature. (C) 2008 Elsevier Ltd. All rights reserved.
  • Effects of Metal Doping on the Spin-Crossover Properties of an Iron(II) Complex with Extended pi-Conjugated Schiff-Base Ligand Having an N4O2 Donor Set, Zhong Yu, Takayoshi Kuroda-Sowa, Hiroaki Kume, Takashi Okubo, Masahiko Maekawa, Megumu Munakata, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 82(3), 333 - 337, Mar. 2009 , Refereed
    Summary:The spin-crossover (SCO) complex [Fe(qnal)(2)]center dot CH2Cl2 (1), (Hqnal: N-(8'-quinolyl)-2-hydroxy-1-naphthaldimine) with an N4O2 donor set, has been synthesized and characterized. Investigation of magnetic properties shows that the complex exhibits an abrupt and complete spin transition with a 5 K wide thermal hysteresis loop. The X-ray diffraction analysis of complex 1 reveals that the molecules are connected into a quasi one-dimensional chain through extended pi-pi interactions between aromatic rings of ligands. The effects of metal doping on SCO properties have been investigated in the mixed-metal system [Fe1-xMx(qnal)(2)]center dot CH2Cl2 (M = zinc(II) and nickel(II)). The results reveal that metal doping increases the gradual character of spin transition, and no marked differences found between zinc and nickel doping, which suggest the dominant effect of the doping-degree (concentration) rather than metal species on cooperativity. However, the metal doping shows different effects on critical temperature (T-1/2), where a more pronounced descending of T-1/2 is observed in response to increased Zn-doping than in Ni-doping, indicating the noticeable consequence of internal pressure due to the different radii of doping metal ions.
  • {6,6 '-Dimethoxy-2,2 '-[naphthalene-2,3-diylbis(nitrilomethylidyne)]diphenolato}thiocyanatocobalt(III) diethyl ether dichloromethane solvate, Zhong Yu, Takayoshi Kuroda-Sowa, Atsuhiro Nabei, Masahiko Maekawa, Takashi Okubo, ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, 65(3), M257 - U298, Mar. 2009 , Refereed
    Summary:In the title complex, [Co(C(26)H(20)N(2)O(4))(NCS)]center dot C(4)H(10)O center dot CH(2)Cl(2), the pentacoordinated Co(III) atom exhibits a distorted square-pyramidal geometry with an N,N',O,O' tetradentate Schiff base ligand in the basal plane and one thiocyanate ligand at the apical site. The diethyl ether molecule is located in a cavity provided by four O atoms of the ligand with weak C-H center dot center dot center dot O interactions, generating two short O center dot center dot center dot O contact distances [2.766 (3) and 2.745 (3) angstrom] between the diethyl ether molecule and the ligand. The crystal structure is stabilized by the weak C-H center dot center dot center dot O and C-H center dot center dot center dot N interactions and pi-pi interactions between the naphthyl ring system and the benzene ring [centroid-centroid distance = 3.657 (5) angstrom] and between the two naphthyl ring systems [centroid-centroid distance = 4.305 (2) angstrom].
  • {6,6 '-Dimethoxy-2,2 '-[o-phenylenebis(nitrilomethylidyne)]diphenolato}cobalt(II) dichloromethane disolvate, Atsuhiro Nabei, Takayoshi Kuroda-Sowa, Takashi Okubo, Masahiko Maekawa, Megumu Munakata, ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, 65(2), M188 - U669, Feb. 2009 , Refereed
    Summary:The title compound, [Co(C(22)H(18)N(2)O(4))]center dot 2CH(2)Cl(2), was isolated from the reaction of N,N '(o-phenylene)bis(vanillalimine) (H(2)L) with Co(SCN)(2). The crystal structure contains a Co(II) ion surrounded by the L(2-) ligand in a slightly distorted square-planar fashion. Intermolecular C-H center dot center dot center dot O hydrogen-bonding contacts between the dichloromethane solvent molecules and the methoxy or carboxylate O atoms are observed in the crystal structure. The planar complex molecules stack through inversion related pi-pi interactions between the six-membered rings of the vanillalimine half ligands. The distance between centroids is 3.498 (2) angstrom and the perpendicular distance is 3.345 angstrom. A partial stacking is observed with a centroid-centroid distance of 3.830 (2) angstrom, a perpendicular distance of 3.350 angstrom and a slippage of 1.856 angstrom.
  • A unique chair-shaped hexanuclear Cu(I) metallamacrocyclic C2H4 adduct encapsulating a BF4- anion, Masahiko Maekawa, Atsuhiro Nabei, Toshi Tominaga, Kunihisa Sugimoto, Toshie Minematsu, Takashi Okubo, Takayoshi Kuroda-Sowa, Megumu Munakata, Susumu Kitagawa, DALTON TRANSACTIONS, DALTON TRANSACTIONS, (3), 415 - 417, 2009 , Refereed
    Summary:Three novel Cu(I)-C2H4 adducts bearing 4-(2-pyridyl)-pyrimidine were self-assembled, and the roles of anion and solvent were proved in the formation process.
  • The effect of molecular packing on the occurrence of spin crossover phenomena in one-dimensional Fe(II)-bis-Schiff base complexes, Atsuhiro Nabei, Takayoshi Kuroda-Sowa, Takashi Okubo, Masahiko Maekawa, Megumu Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 361(12-13), 3489 - 3493, Sep. 2008 , Refereed
    Summary:Two new one-dimensional Fe(II)-bis-Schiff base complexes, [Fe(L1)(pyz)] center dot CH(2)Cl(2) (1) and [Fe(L2)(pyz)] center dot 2CH(2)Cl(2) (2) (H(2)L1 = bis(O-vanillin)-O-phenylenediimine, H(2)L2 = bis(O-vanillin)-2,3-naphthalenediimine, pyz = pyrazine) are reported with their crystal structures and magnetic property. Compound 1 shows a two-step SCO behavior while 2 shows HS at all the temperature range measured. Although the extension of aromatic moiety from benzene (L1) to naphthalene (L2) was introduced for the purpose of strengthening the cooperativity, it leads to the absence of SCO, due to the unanticipated pi-pi interaction, which leads to the longer Fe-N bond lengths and a weak ligand field around Fe(II) ion. (c) 2008 Elsevier B. V. All rights reserved.
  • 1D chain and 3D framework of silver(I) organo-metallic polymers self-assembled with triptycene, Ming Wen, Megumu Munakata, Yi-Zhi Li, Yusaku Suenaga, Takayoshi Kuroda-Sowa, Masahiko Maekawa, Manabu Anahata, POLYHEDRON, POLYHEDRON, 26(12), 2455 - 2460, Jul. 2007 , Refereed
    Summary:For the purpose of investigating the coordination behavior of sterically congested alkenes and exploring the possibility of non-planar complexation in the polycyclic aromatic system for formation of extended polymeric networks, triptycene (tpty) has been studied with regard to its complexation with the silver(I) ion. The crystal structures of [Ag(tpty)(THF)(2)](ClO4) (1) and [Ag-6(tPtY)(4)(CF3SO3)(2-)(H2O)(6)](CF3SO3)(4) (2) have been determined by single-crystal X-ray diffraction. The polycyclic aromatic hydrocarbon triptycene is found to offer a potential site for complexation, which can be utilized to generate an interesting array of organo-metallic polymers with one-dimensional (1D) chain and three-dimensional (3D) porous frameworks. (c) 2007 Elsevier Ltd. All rights reserved.
  • A MLCT-switched photochromic copper(II) coordination polymer with 1,2-bis(2 '-methyl-5 '-(4 ''-pyridyl)-3 '-thienyl)perfluorocyclopentene in crystalline phase, Megumu Munakata, Jing Han, Masahiko Maekawa, Yusaku Suenaga, Takayoshi Kuroda-Sowa, Atsuhiro Nabei, Hideaki Ensu, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 360(8), 2792 - 2796, May 2007 , Refereed
    Summary:A novel Cu(II) coordination polymer with photochromic 1,2-bis(2'-methyl-5'-(4 ''-pyridyl)-3'-thienyl)perfluorocyclopentene (BM-4-PTP) was prepared and crystallographically characterized. Its photochromic behavior as well as magnetic property was investigated in crystalline phase. In complex [Cu(BM-4-PTP)Br-2(DMF)(2)] (1), each copper atom is bridged by two N atoms of BM-4-PTP, two Br atoms from anions and two O atoms of DMF in an slightly distorted octahedral geometry. The basal planar center is in turn linked by bidentate ligand forming a 1-D polymeric chain. Free ligand showed typical spectral changes upon appropriate optical excitation, indicating the reversible photochromism in crystalline phase. Complex 1 occurred reversible photoisomerization not only through the pi-pi* transition but also the MLCT transition in crystalline phase. On the other hand, the magnetic property of complex 1 has been investigated by means of ESR. The spectra slightly and reversibly changed in response to UV and visible light supporting the normal photoreactivity in crystalline phase. (C) 2006 Elsevier B.V. All rights reserved.
  • Photochromism of novel metal coordination polymers with 1,2-bis(2 '-methyl-5 '-(carboxylic acid)-3 '-thienyl)perfluorocyclopentene in the crystalline phase, Jing Han, Masahiko Maekawa, Yusaku Suenaga, Hideaki Ebisu, Atsuhiro Nabei, Takayoshi Kuroda-Sowa, Megumu Munakata, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 46(8), 3313 - 3321, Apr. 2007 , Refereed
    Summary:Three new metal complexes with 1,2-bis(2'-methyl-5'-(carboxylic acid)-3'-thienyl)perfluorocyclopentene (BM-5-CATP) were synthesized and characterized by X-ray diffraction analysis. BM-5-CATP serves as a bis-monodentate ligand that bridges metal centers to generate three 1D polymers. The two thienyl rings in the three complexes adopt antiparallel fashions, and the distances of 3.39, 3.53, and 3.57 angstrom between the two reactive carbons are short enough to allow photocyclizations to occur in the crystalline phase. [Co(BM-5-CATP)(py)(2)(MeOH)(2)] (1) displayed effective photoisomerization in the crystalline phase. Interestingly, solvated 1 underwent a solid-state conversion upon heating to generate, through the release of the coordinated MeOH and rearrangement of the coordination geometry, the desolvated form (1a), while maintaining reversible photochromism. The removal of the solvent led to obvious changes in physical properties such as color and magnetic properties. The ESR spectra of 1 and 1a changed reversibly upon photoexcitation, indicating changes in coordination geometry accompanied by photoreaction. The magnetic susceptibilities of 1 and 1a showed no obvious changes, suggesting that the cobalt-cobalt interaction through the long bridging BM-5-CATP is less effective. Both [Cu(BM-5-CATP)(py)(3)](EtOH)(py)(1.8) (2) and [Zn(BM-5-CATP)(phen)(H2O)] (3) exhibited reversible photoreactions in the crystalline phase. However, 3 did not show remarkable spectral changes because of steric hindrance from the coordinated bulky phenanthroline and the intramolecular H bonds.
  • Bowl-shaped Cu(I) metallamacrocyclic ethylene and carbonyl adducts as structural analogues of organic calixarenes, Masahiko Maekawa, Hisashi Konaka, Toshie Minematsu, Takayoshi Kuroda-Sowa, Megumu Munakata, Susumu Kitagawa, CHEMICAL COMMUNICATIONS, CHEMICAL COMMUNICATIONS, (48), 5179 - 5181, 2007 , Refereed
    Summary:Three novel Cu(I) metallacalixarenes with C2H4 and CO legs, in which an anion is accommodated in the inside cavity, were self-assembled by anion templation and have been structurally characterized.
  • Syntheses, structures and photochromism of two novel copper(II) complexes with 1,2-bis(2 '-methyl-5 '-(2 ''-pyridyl)-3 '-thienyl)perfluorocyclopentene, Megurnu Munakata, Jing Han, Atsuhiro Nabei, Takayoshi Kuroda-Sowa, Masahiko Maekawa, Yusaku Suenaga, Nozomu Gunjima, POLYHEDRON, POLYHEDRON, 25(18), 3519 - 3525, Dec. 2006 , Refereed
    Summary:Two novel Cu(II) complexes with 1,2-bis(2'-methyl-5'-(2"-pyridyl)-3'-thienyl)perfluorocyclopentene (BM-2-PTP) or its closed-form (closed-BM-2-PTP) were synthesized and characterized by X-ray crystallographic analysis. Both complexes are tetra-coordinated to two N atoms from distinct ligands and two Cl atoms from anions, forming 1-D polymeric structures. [Cu(BM-2-PTP)Cl-2] (1) showed typical spectral changes as analogous Ag(I) complexes with the same ligand upon appropriate light stimulus. However, closed-BM-2PTP displayed different photocyclization from its open-ring form upon irradiation with UV light, indicating the photogenerated closed form turned into two kinds of closed-ring isomers. Furthermore, [Cu(closed-BM-2-PTP)Cl-2] (2) was revealed to contain two conformers by X-ray crystallographic analysis and displayed similarities in photocyclization to its free ligand. The distinct absorptions of the UV spectrum were attributed to the coexistence of two conformers in complex 2, both of which showed effective photo reactivities in the crystalline phase. The photochromic mechanism of complex 2 is tentatively concluded as two conformers displaying independent photoreactions. (c) 2006 Published by Elsevier Ltd.
  • Reversible photochromism of novel silver(I) coordination complexes with 1,2-bis(2 '-methyl-5 '-(2 ''-pyridyl)-3 '-thienyl)perfluorocyclopentene in crystalline phase, Megumu Munakata, Jing Han, Atsuhiro Nabei, Takayoshi Kuroda-Sowa, Masahiko Maekawa, Yusaku Suenaga, Nozomu Gunjima, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 359(13), 4281 - 4288, Oct. 2006 , Refereed
    Summary:Three novel silver(l) complexes with 1,2-bis(2-methyl-5'-(2"-pyridyl)-3'-thienyl)perfluorocyclopentene (BM-2-PTP) were synthesized by the reaction of Ag(CF3SO3) or Ag(CF3COO) with BM-2-PTP in benzene at different temperatures. The structures of these metal complexes were revealed by X-ray crystallographic analyses and the correlation between crystal structures and photochromic performance was discussed. In complexes 1 and 2, silver(I) is three-coordinated to two nitrogens from distinct ligand molecules as well as one oxygen from anions to form a I-D polymeric structure. On the other hand, complex 3 contains two crystallographic independent Ag(I) with different coordination environments, and the adjacent BM-2-PTP molecules are connected by Ag-CF3CO2-Ag chains to afford a I-D double chain structure. The difference in structures of three complexes shows the interesting anionic effect on coordination and the subtleness of crystal engineering. It is noted that complex 3 underwent reversible photochromic reaction in crystalline state despite the unfavorable framework to the rotation of thiophene groups. (c) 2006 Elsevier B.V. All rights reserved.
  • Photochromic Rh(II) complexes based on 1,2-dicyano-1,2-bis(2,4,5-trimethyl-3-thienyl)ethene, Jing Han, Atsuhiro Nabei, Yusaku Suenaga, Masahiko Maekawa, Hiromichi Isihara, Takayoshi Kuroda-Sowa, Megumu Munakata, POLYHEDRON, POLYHEDRON, 25(13), 2483 - 2490, Sep. 2006 , Refereed
    Summary:Reaction of [Rh-2(O2CC(CH3)(3))(4)] with cis-1,2-dicyano-1,2-bis(2,4,5-trimethyl-3-thienyl)ethene (cis-dbe) or closed-dbe in benzene and dichloromethane yielded three novel Rh(II) complexes. Their structures were characterized and photochromic properties were studied. X-ray crystallographic analyses revealed that the coordination environments of the three metal complexes are quite different. Complex 2 exhibits a 1-D infinite chain structure with two cyano groups of the ligand bridging two metal ions while in complexes 1 and 3 the metal ions have a direct interaction with at least one of the sulfur atoms of the two bisthienylethene molecules. Closed-dbe of complex 3 was transferred to the ring-open form in the crystalline phase upon photoexcitation with 529 nm light. It underwent a photocycloreversion reaction although the metal atom is coordinated to the thienyl group. The irreversible cyclization reaction was presumably attributed to the fixed rotation of thienyl rings, short Rh-S distance and steric hindrance of anions. (C) 2006 Elsevier Ltd. All rights reserved.
  • Sandwich-shaped silver(I) metallomacrocycles encapsulating a XF62-(X = Si, Ge and Sn) anion, M Maekawa, S Kitagawa, T Kuroda-Sowa, M Munakata, CHEMICAL COMMUNICATIONS, CHEMICAL COMMUNICATIONS, (20), 2161 - 2163, May 2006 , Refereed
    Summary:A series of sandwich-shaped complexes based on two square tetranuclear Ag(I) metallomacrocycles, {[Ag-4(pprd)(4)](2)(XF6)}(BF4)(6)center dot 8MeNO(2) (pprd = 4-(2-pyridyl)pydmidine; X = Si, Ge and Sri), in which a XF62- anion is encapsulated, were prepared and their structures were characterized both in the solid state and solution.
  • Silver(I) coordination complexes of 1,10-phenanthroline-5,6-dione with 1D chain and 2D network structure, Ming Wen, E. Kejia, Megumu Munakata, Yusaku Suenaga, Takayoshi Kuroda-Sowa, Masahiko Maekawa, Sheng Gang Yan, MOLECULAR CRYSTALS AND LIQUID CRYSTALS, MOLECULAR CRYSTALS AND LIQUID CRYSTALS, 457, 203 - 213, 2006 , Refereed
    Summary:Two silver( I) coordination complexes of 1,10-phenanthroline-5,6-dione (pdon), [Ag-2(pdon)(2)(ClO4)(2)] (1) and [Ag( pdon)(2)](CF3SO3) (2), have been synthesized and characterized by elemental analysis, IR, and X-ray diffraction analysis. Using AgClO4 with pdon, the central silver(I) is bridged by ligand pdon with two N and one O atoms and lead to the one-dimensional (1D) chain structure in 1. When triflate anion is used as a counter ion in 2, the silver(I) is chelated by two ligands with four N atoms, and then the molecular unit is linked by intermolecular hydrogen bond to afford a novel two-dimensional (2D) network architecture.
  • Syntheses and structures of photochromic molybdenum(II) and rhodium(II) complexes with 1,2-dicyano-1,2-bis(2,4,5-trimethyl-3-thienyl)ethene, J Han, H Konaka, T Kuroda-Sowa, M Maekawa, Y Suenaga, H Isihara, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 359(1), 99 - 108, Jan. 2006 , Refereed
    Summary:Four novel Mo(II) and Rh(II) complexes with cis-1,2-dicyano-1,2-bis(2,4,5-trimethyl-3-thienyl)ethene (cis-dbe) or closed-dbe were synthesized and characterized. Employing [M(O2CCF3)(4)] (M = Mo, Rh) with cis-dbe or closed-dbe afforded complex [MO2(O2CCF3)(4)(cis-dbe)](benzene) (1), [Rh-2(O2CCF3)(4)(cis-dbe)](benzene) (2), [{MO2(O2CCF3)(4)}(2)(closed-dbe)] (3), and (Rh-2(O2CCF3)(4)(closed-dbe)](p-xylene) (4). The structures of four metal complexes were revealed by X-ray crystallographic analyses and the correlation between the crystal structures and the photochromic performance was discussed. In all complexes, two cyano groups of the ligand bridged two dimetal carboxylates to give a 1-D zigzag infinite chain structure. Upon irradiation with 405 nm light, complex 1 turned into reddish purple from yellow, and the color reverted to initial yellow on exposure to 563 nm light, indicating the reversible cyclization/ring-opening reaction in the crystalline phase. However, the Rh(II) complex 2 did not display similarities in reaction induced by light, which is attributable to the lower ratio of photoactive anti-parallel conformers compared with complex 1 and coordination effect of metal ions on photochromism of diarylethenes. The complexes of Rh(II) ions did not exhibit the expected reversible photoinduced behavior. (c) 2005 Elsevier B.V. All rights reserved.
  • Syntheses and structural characterization of mononuclear Rh-Cp* and Ir-Cp* complexes with eta(6)-phenanthrene, eta(6)-pyrene and eta(6)-triphenylene, M Maekawa, T Minematsu, A Nabei, H Konaka, T Kuroda-Sowa, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 359(1), 168 - 182, Jan. 2006 , Refereed
    Summary:Four novel mononuclear Rh-Cp* and Ir-Cp* complexes with polycyclic aromatic hydrocarbons (PAHs), [M(Cp*)(eta(6-)PAHs)](BF4)(2)(M= Rh and Ir; Cp* = eta(5)-C5Me5; PAHs = phenanthrene (phn), pyrene (pyr) and triphenylene (triph)), were prepared by the reactions of the intermediate [M(Cp*)(Me2CO)(3)](2+) with appreciable PAHs. Their structures were characterized by a single crystal X-ray analysis, H-1, C-13 {H-1} NMR and 2D NMR techniques. The X-ray crystallographic studies showed that the [M(Cp*)](2+) fragment is eta(6-)coordinated to one terminal benzene ring in each PAH. In particular, it is interesting to note that the partial pi/pi/pi/pi interaction was formed in the Ir-pyr complex [Ir(Cp*)(eta(6)-pyr)](BF4)(2). The 1D and 2D NMR studies described that the Rh-Cp* and Ir-Cp* complexes with PAHs gave unique H-1 and 13C [ 1 H I NMR spectra with positive coordination shifts (Delta delta(H-1, C-13) in (CD3)(2)CO at 23 degrees C, which are likely induced by the local effect and the non-local effect on the coordination of the [M(Cp*)]2+ fragment to PAHs. The decreasing of the coupling constants ((3)J(H-H)) in the eta(6)-Coordinated benzene ring is also induced, with no changes in the uncoordinated benzene rings. The time-course of 1H NMR spectra showed that Rh-Cp* and Ir-Cp* complexes with PAHs are partially dissociated to [M(Cp*)(Me2CO)(3)](2+) and metal-free PAHs in (CD3)2CO at 23 degrees C. It was demonstrated that their stabilities are in the order of Ir-triph, Ir-phn, Ir-pyr and Rh-triph complexes in (CD3)(2)CO. (c) 2005 Elsevier B.V. All rights reserved.
  • Syntheses, crystal structures and magnetic properties of Mn-12 single-molecule magnets with diphenylphosphate and their tetraphenylphosphonium salts, T Kuroda-Sowa, GQ Bian, M Hatano, H Konaka, S Fukuda, S Miyoshi, M Maekawa, M Munakata, H Miyasaka, M Yamashita, POLYHEDRON, POLYHEDRON, 24(16-17), 2680 - 2690, Nov. 2005 , Refereed
    Summary:The preparation and physical characterization are reported for a family of novel Mn-12 single-molecule magnets having diphenyl-phosphate (labeled dppH) bridges, [Mn12O12(O2CR)(16-x)(dpp)(x)(H2O)(y)] (R = CH3: x = 4, y = 0 (1); x = 8, y = 2 (2), R = Ph: x = 4, y = 4 (5); x = 8, = 4 (6), and R = Et: x = 4, y 4 (9)) and their tetraphenyl phosphate salts [Ph4P][Mn12O12(O2CR)(16-x)(dpp)(x)(H2O)(4)] (R = CH3: x = 4 (3); x 8 (4) and R = Ph: x = 4 (7); x = 8 (8)). The crystal structures of I and 5 were characterized by X-ray. The X-ray structure analysis of I reveals that there are four five-coordinate Mn-III ions with (MnH)-H-... approaches and without coordinating water molecules. The H-1 NMR measurements show H2O can coordinate to a vacant site of 1 in CD2Cl2 solution. Ac magnetic susceptibility measurements indicate that nine complexes are single-molecule magnets. The increase of the number of dpp(-) ligands resulted in a decrease of the U-eff values of neutral Mn-12 SMMs estimated from ac measurements. Complexes 1 and 5 show a quantum tunneling behavior, whose ground states were tentatively assigned to S = 10 with g = 1.78, and D = -0.60 K; S = 10 with g = 1.92, and D = -0.63 K, respectively. (c) 2005 Elsevier Ltd. All rights reserved.
  • Syntheses, crystal structure, and magnetic properties of Mn-12 single-molecule magnets with naphthalenecarboxylate bridges, [Mn12O12(O2CC10H7)(16)(H2O)(4)] and their tetraphenylphosphonium salts, GQ Bian, T Kuroda-Sowa, T Nogami, K Sugimoto, M Maekawa, M Munakata, H Miyasaka, M Yamashita, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 78(6), 1032 - 1039, Jun. 2005 , Refereed
    Summary:The preparation and physical characterization are reported for three Mn-12 single-molecule magnets (SMMs) having naphthalenecarboxylate bridges, [Mn12O12(2-nc)(16)(H2O)(4)] (1, 2-ncH = 2-naphthalenecarboxylic acid), its Ph4P+ salt (2) and [Mn12O12(1-nc)(16)(H2O)(4)] (3, 1-ncH = 1-naphthalenecarboxylic acid). Complex 1 center dot 2CH(2)Cl(2)center dot 4.5H(2)O crystallizes in the monoclinic space group C2/c, with cell dimensions at -160 degrees C of a = 28.524 angstrom, b = 17.819 angstrom, c = 36.058 angstrom, beta = 92.399 degrees, and Z = 4. The X-ray structure analysis of 1 center dot 2CH(2)Cl(2)center dot 4.5H(2)O reveals that each [Mn-12] molecule is connected to the neighboring molecules through eight pi... pi interactions to form a two-dimensional structure within the bc-plane. This is the first SMM that self-assembles two-dimensionally via pi... pi interaction. From Arrhenius plots of the frequency dependence of the temperatures of the X"(M) peaks, the effective energy barriers U-eff for the reversal of the magnetization spin were estimated to be 61 K, 53 K, and 61 K for high-temperature phases of 1-3, respectively, and 31 K and 33 K for the low-temperature (UT) phases of 1 and 3, respectively. The analysis of the reduced magnetization data suggests that the LT phase of I has an S = 9 ground state with g = 1.998 and D = -0.61 K.
  • Synthesis and crystal structures of silver(I) bridged tetra-phenyl-pyrylium complexes from tetraphenyl-cyclopentadiene, GL Ning, XC Li, WT Gong, M Munakata, M Maekawa, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 358(7), 2355 - 2362, Apr. 2005 , Refereed
    Summary:Reactions of silver(1) perchlorate with tetraphenyl-cyclopentadiene (Ph4H2-C-5) have isolated two novel silver(1) bridged tetraphenyl-pyrylium complexes: [Ag(ClO4)(Ph4HC5O+)](ClO4)(-) (1) and [Ag(ClO4)(H2O)(Ph4HC5O+)](ClO4-) (2), depending on moisture-content of the reactants. Structure studies using single-crystal X-ray diffraction have showed that complex 1contains a distorted tetrahedral metal center bridging two neighboring peripheral phenyl rings of one pyrylium cation and two perchlorate anions, whereas 2 involves a three-coordinate metal ion interacting with a pair of phenyl rings and one water molecule, leaving two perchlorate anions free from coordination. For both complexes, the precursor ligand Ph4H2C5 undergoes a ring-enlargement reaction, forming a six-membered pyrylium cation. The fundamentals of the synthesis, structure characterization and some properties are discussed. (c) 2005 Elsevier B.V. All rights reserved.
  • Silver(l) compounds consisting of [2.2]paracyclophane: Reversible guest-driven solid-state transformation and incorporation behavior, T Kuroda-Sowa, SO Liu, Y Yamazaki, M Munakata, M Maekawa, Y Suenaga, H Konaka, H Nakagawa, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 44(6), 1686 - 1692, Mar. 2005 , Refereed
    Summary:Reaction of [2.2]paracyclophane with silver(l) heptafluorobutyrate (AgC3F7CO2) has isolated three novel networks: [Ag-4(PCP)(C3F7CO2)(4)](.)pyrene (1), [Ag-4(PCP)(C3F7CO2)(4)](.)phen (phen = phenanthrene) (2), and [Ag-4(PCP)(C3F7CO2)(4)](.) fluorene (3), and an intercalation compound [Ag-4(PCP)(C3F7CO2)(4)](.)2benzene (4). All the four complexes exhibit two-dimensional (2D) sheet structures in which AgC3F7CO2 form an infinite chain and pcp acts as linkage. 1, 2, and 3 show 2D flat sheets with cavities in which guest molecules are situated, whereas 4 exhibits 2D zigzag layers between which guest benzene molecules are intercalated. Pcp shows mu-di-eta(1)-eta(2) coordination mode in 1, mu-tetra-eta(1) coordination mode in 2 and 3, and mu-tetra-eta(2) coordination mode in 4. The reversible guest exchanges were observed between complex 1, 2, or 3 and intercalation compound 4. It is unprecedented for metal-organic inclusion complexes that the guest exchange occurs where the guest is the solute molecule. Furthermore, 4 can release the guest, and the original framework was completely recovered after reincorporation of benzene. It should be noted that 4 can incorporate pyrene, phen, and fluorene to give 1, 2, and 3, respectively, after desorption.
  • Synthesis and structural characterization of dinuclear iridium hydrido complex with 3,6-bis(2-pyridyl)tetrazine, [Ir-2(H)(4)(PPh3)(4)(bptz)](PF6)(2) center dot 4CH(2)O(2), M Maekawa, H Konaka, T Minematsu, T Kurorda-Sowa, Y Suenaga, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 358(4), 1317 - 1321, Mar. 2005 , Refereed
    Summary:Reaction of the precursor Ir complex [Ir(H)(2)(PPh3)(2)(Me2CO)(2)]PF6 with 3,6-bis(2-pyridyl)tetrazine (bptz) in CH2Cl2 gave a novel dinuclear Ir hydrido complex [Ir-2(H)(4)(PPh3)(4)(bptz)](PF6)(2) center dot 4CH(2)Cl(2). Crystallographic study described an interesting coordination environment having a pi-pi interaction and H-1 NMR study showed unique uptield shifts of pyridyl rings that are likely induced by the ring current effect of neighboring PPh3 ligands. (c) 2004 Elsevier B.V. All rights reserved.
  • First crystallographic determination of dichloro-bridged dinuclear rhodium Cp* complex with neutral Me2CO molecules. [Rh-2(Cp*)(2)(mu-Cl)(2)(Me2CO)(2)](BF4)(2) (Cp* = eta(5)-C5Me5), M Maekawa, Y Kayanuma, A Nabei, T Kuroda-Sowa, Y Suenaga, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 358(4), 1313 - 1316, Mar. 2005 , Refereed
    Summary:The single crystals 5 of dichloro-bridged dinuclear Rh-Cp* complex with neutral Me2CO molecules, [Rh-2(CP*)(2)(mu-Cl)(2)(Me-2-CO)(2)](BF4)(2) (CP* = eta(5)-C5Me5), was isolated and the structure was in first determined crystallographically. (c) 2004 Elsevier B.V. All rights reserved.
  • 3D coordination polymers of [2.2]paracyclophane and in situ silver(I) perfluoro-dicarboxylates: effects of the dicarboxylate spacers and conformations on the formation of complexes, SQ Liu, H Konaka, T Kuroda-Sowa, M Maekawa, Y Suenaga, GL Ning, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 358(4), 919 - 926, Mar. 2005 , Refereed
    Summary:Coordination polymers of [2.2]paracyclophane (pep) with in situ silver(l) perfluoro-dicarboxylates characterized by single crystal X-ray analysis are described. Structures are found to strongly depend on the dicarboxylate spacer (n). With disilver(l) tetrafluorosuccinate ((CF2)(n)(COOAg)(2), n = 2), 3D network with composition of [Ag-4(PCP)(C2F4(CO2)(2))(2)] (1) forms in which silver salts afford infinite double chains and pep act as linkages between chains. Changing the silver salt to disilver hexafluoroglutarate ((CF2)(n)(COOAg)(2), n = 3) produces 3D pillared-layer structure of composition of [Ag-4(pcp)(C3F6(CO2)(2))(2)] (.) THF (2) (THF = tetrahydrofuran), in which silver salts form 2D sheets and pep act as pillars between the sheets. With silver octafluoroadipate (HO2C(CF2),CO2Ag, n = 4), 2-fold interpenetrated diamond structure, [Ag-2(pcp)(2)(HO2CC4F8CO2)(2)](2) (.) 2toluene (3), is obtained in which silver-anion chains and silver-pcp chains are connected with each other in the perpendicular manner. The three complexes represent unprecedented metal-organic networks of silver(I) multicarboxylates and polycyclic aromatic compounds. Additionally, the effects of the dicarboxylate conformations as well as the solvents on the resulting structures were discussed. (c) 2004 Elsevier B.V. All rights reserved.
  • catena-poly[[chlorodipyridine-manganese(II)]-mu(3)-6-oxo-1,6-dihydro-pyridine-2-carboxylato], GQ Bian, T Kuroda-Sowa, S Sugimoto, M Maekawa, M Munakata, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, 61, M144 - M146, Mar. 2005 , Refereed
    Summary:The title one-dimensional chain polymer complex, [Mn(C6H4NO3)Cl(C6H5N)(2)](n), was isolated from the reaction of MnCl2 with 6-oxo-1,6-dihydropyridine-2-carboxylic acid (HpicOH) in pyridine. The asymmetric unit contains one [Mn(HPicO)Cl(py)(2)] moiety (py is pyridine), with the (HpicO)(-) ligand acting in a tridentate manner via the two carboxylate O atoms and the pyridone O atom. The operation of inversion centres generates eight- and 14-membered rings and, in conjunction with an a-axis translation, leads to an infinite chain extending along [100]. The Mn...Mn separations in this chain are 5.1069 (6) and 7.1869 (6) Angstrom. The Mn-II atom has a distorted octahedral coordination, with trans-axial pyridine ligands and with three O atoms and the Cl atom in the equatorial plane. The conformation of the 14-membered ring is stabilized by pairs of inversion-related N-H...O hydrogen bonds.
  • Silver(l) coordination polymers of fluorescent oligo(phenylenevinylene) with pi-pi stackings: Luminescence and conductivity, SQ Liu, T Kuroda-Sowa, H Konaka, Y Suenaga, M Maekawa, T Mizutani, GL Ning, M Munakata, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 44(4), 1031 - 1036, Feb. 2005 , Refereed
    Summary:Three luminescent silver(I)-oligo(phenylenevinylene) complexes, [Ag-2(bmsb)(ClO4)(2)] (1), [Ag-2(bmsb)(H2O)(4)](BF4)(2) (2), and [Ag-2(bdb)(CF3SO3)(2)] (3) (bmsb = 1, 4-bis(methylstyryl)benzene, bdb = 4,4'-bis(2, 5-dimethylstryryl)biphenyl), have been synthesized and structurally characterized. Complexes 1 and 2 are 2D networks with unique metallocyclophane motifs. Complex 3 affords a 2D zigzag sheet, in which silver triflates form tubelike double chains and bdb molecules act as linkages. Complex 2 exhibits high electric conductivity because of columnar aromatic stackings formed through intra- and intermolecular pi-pi interactions. Complexes 1-3 in the solid state exhibit luminescence, of which excitation and emission maxima are shifted to longer wavelength as compared to those of the corresponding metal-free ligands.
  • MeOH-coordinated Mn-12 single-molecule magnet: structure and magnetic properties of [Mn12O12(OAc)(16)(MeOH)(4)], GQ Bian, T Kuroda-Sowa, N Gunjima, M Maekawa, M Munakata, INORGANIC CHEMISTRY COMMUNICATIONS, INORGANIC CHEMISTRY COMMUNICATIONS, 8(2), 208 - 211, Feb. 2005 , Refereed
    Summary:Complex [Mn12O12(OAc)(16)(MeOH)(4)] having MeOH-coordination was synthesized and characterized, whose magnetic behaviors indicate it is a single-molecule magnet with the largest U-eff/k(B) of 76.2 K. (C) 2004 Elsevier B.V. All rights reserved.
  • catena-Poly[[[diacetonitrilesilver(I)]-mu-2,11-dithia[3.3]paracyclophane-kappa S-2 : S '] tetrafluoroterephthalate tetrafluoroterephthalic acid acetonitrile tetrasolvate], SQ Liu, H Konaka, T Kuroda-Sowa, M Maekawa, Y Suenaga, GL Ning, M Munakata, ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, 60, M1504 - M1506, Oct. 2004 , Refereed
    Summary:The title compound, {[Ag-2(C16H16S2)(2)(C2H3N)(4)](C8F4O4) .2C(8)H(2)F(4)O(4).4C(2)H(3)N}(n) has been prepared from the reaction of 2,11-dithia[3.3]paracyclophane (dtpcp) and in situ silver(l) tetrafluoroterephthalate (TFTP2-) using an interface method. In the solid state the title compound forms two infinite chains, which are parallel to one another. One chain consists of [Ag-2(C16H16S2)(2)(C2H3N)4](n)(2n+) and the other is formed from TFTP2- and H2TFTP via O-c-H...O-c (c is carboxy) hydrogen- bonding interactions, with H...A distances of 1.72 (2) and 1.774 (19) Angstrom. The Ag-I ion is tetrahedrally coordinated by two acetonitrile N atoms and two dtpcp S atoms. The cyclophanes have inversion symmetry.
  • Syntheses and structural characterizations of novel mono- and dinuclear iridium hydrido complexes with polydentate nitrogen donor ligands, M Maekawa, T Minematsu, H Konaka, K Sugimoto, T Kuroda-Sowa, Y Suenaga, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 357(12), 3456 - 3472, Sep. 2004 , Refereed
    Summary:New five mono- and dinuclear Ir hydrido complexes with polydentate nitrogen ligands, [Ir(H)(2)(PPh3)(2)(tptz)]PF6 (1), [Ir-2(H)(4)(PPh3)(4)(tptz)](PF6)(2.2)H2O (2.2H(2)O), [Ir(H)(2)(PPh3)(2)(tppz)]BF4 (3), [Ir-2(H)(4)(PPh3)(4)(tppz)](BF4)(2) (4) and [Ir-2(H)(4)(PPh3)(4) (bted)](BF4)(2).6CHCl(3) (5.6CHCl(3)), were systematically prepared by the reactions of the precursor Ir hydrido complex [Ir(H)(2)(PPh3)(2)(Me2CO)(2)]X (X=PF6 and BF4) With 2,4,6-tris(2-pyridyl)-1,3,5-triazine (tptz), 2,3,5,6-tetrakis(2-pyridyl)pyrazine (tppz) and 1,4-bis(2,2:6,2"-terpyridine-4'-yl)benzene (bted), and their structures and properties were characterized in the solid state and in solution. Each of the Ir hydrido complexes with polydentate nitrogen ligands crystallographically described a unique coordination mode. Their H-1 NMR spectra demonstrated unusual I H NMR chemical shifts of pyridyl rings that are likely induced by the ring current effect of neighboring ligands. (C) 2004 Elsevier B.V. All rights reserved.
  • Dinuclear silver(I) complexes of N,N '-dibenzyl-4,13-diaza-18-crown-6-ether and dibenzo-24-crown-8-ether, M Wen, M Munakata, Y Suenaga, T Kuroda-Sowa, M Maekawa, Kodai, I, POLYHEDRON, POLYHEDRON, 23(13), 2117 - 2123, Aug. 2004 , Refereed
    Summary:Three silver(I) coordination complexes of diaza- and dibenzo-crown ethers, [Ag(DDAc)](CF3SO3) (1), [Ag-2(DDAC)(CF3SO3)(2)] (2) and [Ag-2(DB24C8)(CF3SO3)(2)] (3) have been synthesized by using different molar ratios of ligand to silver triflate salt, and characterized structurally. A large excess of DDAC ligand leads to mononuclear complex 1, and a large excess of silver triflate gives rise to dinuclear complex 2, based on metal-heteroatom and metal-oxygen interactions. Ligand DB24C8 coordinates two silver(I) ions to afford dinuclear complex 3. (C) 2004 Elsevier Ltd. All rights reserved.
  • A Mn-12 single-molecule magnet [Mn12O12(OAc)(12)(dpp)(4)] (dppH = diphenyl phosphate) with no coordinating water molecules, GQ Bian, T Kuroda-Sowa, H Konaka, M Hatano, M Maekawa, M Munakata, H Miyasaka, M Yamashita, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 43(16), 4790 - 4792, Aug. 2004 , Refereed
    Summary:The preparation and physical characterization are reported for a novel single-molecule magnet [Mn12O12(OAc)(12)(dPP)(4)] (dppH = diphenyl phosphate) with no coordinating water molecules. The crystal structure analysis reveals that there are four five-coordinate Mn-III ions with Mn...H approaches. Addition of water in CD2Cl2 solution was monitored by H-1 NMR, which showed that H2O could coordinate to a vacant site of a five-coordinate Mn-III ion in solution. The measurements and analyses of magnetization hysteresis and ac magnetic susceptibility indicate that the title complex is a single-molecule magnet with a quantum tunneling behavior, whose ground state was tentatively assigned to S = 10 with g = 1.78 and D -0.60 K.
  • Bis(mu-6-hydroxypicolinato)-mu-oxo-bis[dipyridinemanganese(III)] monohydrate, GQ Bian, T Kuroda-Sowa, H Konaka, M Maekawa, M Munakata, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, 60, M338 - M340, Jul. 2004 , Refereed
    Summary:The title compound, [Mn-2(mu-O)(C6H3NO3)(2)(C5H5N)(4)].H2O, was isolated from the reaction of 2,6-pyridinedicarboxylic acid with [Mn12O12(CH3COO)(16)(H2O)(4)] in pyridine. The dimanganese complex has twofold symmetry; the Mn-III atoms are bridged by one oxo and two amidate ligands and show compressed octahedral Jahn-Teller distortion. The molecular packing comprises a three-dimensional structure constructed by means of extensive intermolecular interactions, including three kinds of hydrogen bonds and pi-pi interactions.
  • catena-Poly[[[diacetonitrilesilver(I)]-mu-2,11-dithia[3.3]paracyclophane-kappa S-2 : S ']hydrogenoctafluoroadipate, SQ Liu, H Konaka, T Kuroda-Sowa, M Maekawa, Y Suenaga, GL Ning, M Munakata, ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, 60, M865 - M867, Jun. 2004 , Refereed
    Summary:The title compound, {[Ag(C16H16S2)(C2H3N)(2)](C6HF8O4)}(n), forms two infinite chains, which are approximately perpendicular to each other. One chain consists of [Ag(C16H16S2)(C2H3N)(2)](n)(n+), and the other is formed from HOFA(-). (HOFA(-) is hydrogen octafluoroadipate) units via O-c - H ... Oc (c is carboxy) hydrogen-bonding interactions, with an H ... A distance of 1.66 (5) Angstrom. Each silver(I) cation lies on a crystallographic twofold rotation axis and has a tetrahedral geometry, defined by two N atoms belonging to two acetonitrile molecules and two S atoms from two 2,11-dithia[3.3]paracyclophane molecules. The cyclophanes have inversion symmetry.
  • A novel Mn-12 single-molecule magnet with a mu(3)-methanesulfonate bridge, T Kuroda-Sowa, T Handa, T Kotera, M Maekawa, M Munakata, H Miyasaka, M Yamashita, CHEMISTRY LETTERS, CHEMISTRY LETTERS, 33(5), 540 - 541, May 2004 , Refereed
    Summary:The first Mn-12 complex with mu(3)-methanesulfonate bridge was observed and its single-molecular magnetic property was characterised.
  • Conversion of phenyl-substituted cyclopentadienes to pyrylium cations, GL Ning, Cheng, X, M Munakata, WT Gong, M Maekawa, T Kamikawa, JOURNAL OF ORGANIC CHEMISTRY, JOURNAL OF ORGANIC CHEMISTRY, 69(4), 1432 - 1434, Feb. 2004 , Refereed
    Summary:Phenyl-substituted cyclopentadienes are proved to form phenylated pyrylium cations in the presence of silver(l) perchlorate by insertion of an oxygen atom into the cyclopentadiene-ring. Three phenylated pyrylium compounds, [(Ph5C5O+)(ClO4-)](2)(CH2Cl2) (1), Ag(ClO4)(ClO4)(Ph4HC5O+) (ClO4-) (2), and (Ph3H2C5O+)(ClO4-) (3) have been synthesized and characterized. A possible reaction pathway and formation mechanism of the pyrylium cation are proposed and discussed.
  • Crystal structure of chlorobis(1,10-phenanthroline)copper(II) tetrafluoroborate, [Cu(phen)2Cl]BF4, Masahiko Maekawa, Hisashi Konaka, Kunihisa Sugimoto, Yusaku Suenaga, Takayoshi Kuroda-Sowa, Megumu Munakata, Analytical Sciences: X-ray Structure Analysis Online, Analytical Sciences: X-ray Structure Analysis Online, 20(2), x71 - x72, 2004 , Refereed
    Summary:The title Cu(II) complex, [Cu(phen)2Cl]BF4 (phen = 1,10-phenanthroline), was characterized crystallographically, which shows the most near regular trigonal bipyramidal geometry in the five-coordinate [Cu(phen)2Cl]+ series. 2004 © The Japan Society for Analytical Chemistry.
  • Crystal structure of tri-μ-chloro-bis[(1,2,3,4,5-η)-1,2,3,4,5-pentamethyl-2,4- cyclopentadien-1-yl)]-diiridium Tetrafluoroborate with a Unique Trigonal- bipyramidal Ir2Cl3 Core, [Ir2(Cp*)2(μ-Cl)3]BF4 (Cp* = η5-C5Me5), Masahiko Maekawa, Yusaku Suenaga, Takayoshi Kuroda-Sowa, Megumu Munakata, Analytical Sciences: X-ray Structure Analysis Online, Analytical Sciences: X-ray Structure Analysis Online, 20(1), x11 - x12, 2004 , Refereed
    Summary:Colorless single crystals of a dinuclear Ir complex, [Ir2(Cp*)2(μ-Cl)3]BF4 (Cp* =η5-C5Me5), were obtained with a reaction of [Ir(Cp*)(Me2CO)3]2+ and triptycene under Ar. The crystal structure was determined using CCD single crystal XRD data. The two Ir atoms are μ2-bridged by three chloride atoms to provide a dinuclear structure with a unique trigonal-bipyramidal Ir2Cl3 core. 2004 © The Japan Society for Analytical Chemistry.
  • Syntheses, structures, and properties of intercalation compounds of silver(1) complex with [2.2]paracyclophane, M Munakata, SQ Liu, H Konaka, T Kuroda-Sowa, Y Suenaga, M Maekawa, H Nakagawa, Y Yamazaki, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 43(2), 633 - 641, Jan. 2004 , Refereed
    Summary:Reaction of [2.2]paracyclophane (pcp) with silver(l) trifluoroacetate (AgCF(3)CO(2)) and silver(l) pentafluoroproprionate (AgC(2)F(5)CO(2)) has led to isolation of three novel intercalation polymers: [Ag(4)(PCP)(CF(3)CO(2))(4)](C(6)H(6)) (1), [Ag(4)(pcp)(CF(3)CO(2))(4)](C(6)H(3)Me(3)) (2), and [Ag(4)(PCP)(C(2)F(5)CO(2))(4)](PCP) (3). Structure studies using single crystal X-ray diffraction have shown that all compounds contain two-dimensional layered frameworks based on cation-pi interactions, in which pcp exhibits an unprecedented mu-tetra-eta(2) Coordination mode. Guest molecules which weakly interact with the host pcp via C-H(...)pi interactions are intercalated between layers. The guest-eliminated complexes (1a and 2a) and guest-reincorporated ones (1b or 1c and 2b or 2c), accompanied by small structural changes, were confirmed by (1)H NMR, thermogravimetric analysis, mass spectra, and X-ray powder diffraction patterns. The structural changes from 1 --> 1a --> 1c (=11) can take place reversibly in the process of exposure of 1 a to benzene vapor, The original framework of complex 2 is also completely recovered by immersing 2a in mesitylene as well as exposing it to mesitylene vapor.
  • Syntheses and crystal structures of the first iridium complexes with m- and p-terphenyl (tp). {[Ir-2(p-tp)(cod)(2)](BF4)(2) center dot 2CH(2)Cl(2)}(3) and [Ir(m-tp)(eta(5)-C5Me5)](BF4)(2), M Maekawa, Y Suenaga, T Kuroda-Sowa, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 357(1), 331 - 338, Jan. 2004 , Refereed
    Summary:Novel two iridium terphenyl complexes were prepared and their structures were characterized crystallographically. The reaction of [Ir(cod)(2)]BF4 with p-terphenyl (p-tp) in CH2C2, was carried out to afford dinuclear Ir(I) complex {[Ir-2(p-tp)(cod)(2)](BF4)(2) (.) 2CH(2)Cl(2)}(3) (cod = 1, 5-cyclooctadiene) (1 (.) 2CH(2)Cl(2)), whereas the reaction of the intermediate [Ir(eta(5)-C5Me5)(MeCO)(3)](3+) in Me2CO with m-terphenyl (m-tp) was done to provide mononuclear Ir(III) complex [Ir(m-tp)(eta(5)-C5Me5)](BF4)(2) (2). In complex 1 (.) 2CH(2)Cl(2) two Ir atoms are eta(6)-coordinated to both sides of terminal benzene rings from the upper and lower sides in the p-tp ligand, while one Ir atom is eta(6)-coordinated to one side of the terminal benzene ring in the m-tp ligand in complex 2. Each crystal structure describes the first coordination mode found in metal complexes with the m- and p-tp ligands. (C) 2003 Elsevier B.V. All rights reserved.
  • Synthesis, crystal structure and magnetic properties of novel Mn-12 single-molecule magnets with thiophenecarboxylate, [Mn12O12(O2CC4H3S)(16)(H2O)(4)], and its tetraphenylphosphonium salt, T Kuroda-Sowa, T Nogami, H Konaka, M Maekawa, M Munakata, H Miyasaka, M Yamashita, POLYHEDRON, POLYHEDRON, 22(14-17), 1795 - 1801, Jul. 2003 , Refereed
    Summary:The preparation and physical characterization are reported for novel Mn-12 single-molecule magnets having thiophenecarboxylate bridges, [Mn12O12(O2CC4H3S)(16)(H2O)(4)] (1), and its PPh4 salt (2). The reaction of the excess amount of 2-thiophenecarboxylic acid (tpcH) and [Mn12O12(OAc)(16)(H2O)(4)] in CH2Cl2 gave black crystals of 1, which could be reduced by PPh4I to give 2. From the crystal structure analysis of 2, it is revealed that there are two five-coordinated Mn ions, one of which is assigned to a Mn-II ion being in the vicinity of the tetraphenylphosphoniurn cation. Both complexes exhibit out-of-phase a.c. magnetic susceptibility (chi(M)'') signals in the 5.0-6.5 K range at 997 Hz a.c. frequency, which indicate that they are single-molecule magnets. From Arrhenius plots of the frequency dependence of the temperature of the chi(M)'' peaks, the effective energy barriers U-eff were estimated to be 69 and 57 K for high-temperature phases of 1 and 2, respectively, and 40 K for the low-temperature phase of 1. The reduced magnetization measurement and its analysis indicate that 2 has S = 19/2 ground state with g = 1.99 and D = -0.61 K. (C) 2003 Elsevier Science Ltd. All rights reserved.
  • Two-dimensional silver(I) coordination polymer with twisted naphthalene rings, Y Suenaga, H Konaka, K Kitamura, T Kuroda-Sowa, M Maekawa, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 351, 379 - 384, Jul. 2003 , Refereed
    Summary:The silver(I) complex of octakis(cyclohexylsulfanyl)-naphthalene (ochsn), [Ag-4(ochsn)(CF3COO)(4)](CH2Cl2) (1), has been prepared and its molecular structure was determined by X-ray crystallography. In 1, the silver ion prefers a tetrahedral coordination geometry comprised of two S atoms from the ochsn molecules and the two O atoms from the counter anion then producing two-dimensional sheet structure. Interestingly, the naphthalene ring in the complex has large deviations from planarity and end-to-end twists on the order of 35degrees. In contrast, the central naphthalene ring of ochsn shows almost a planar structure in the solid state. (C) 2003 Elsevier Science B.V. All rights reserved.
  • Cluster-cracking reaction, a new method to synthesize unsymmetrical dithiolate complexes for the study of third-order nonlinear optical properties, GQ Bian, QY Zhu, J Dai, Wang, X, W Yang, ZM Yan, ZR Sun, M Munakata, M Maekawa, CHINESE JOURNAL OF CHEMISTRY, CHINESE JOURNAL OF CHEMISTRY, 21(5), 537 - 543, May 2003 , Refereed
    Summary:A new cluster-cracking method to synthesize dithiolate metal complexes was reported and four unsymmetric complexes with formula (Me4N)(2)[M(Ln)(SPh)(2)] (M = Cd and Zn, L1 = dmit = 1, 3-dithiole-2-thione-4, 5-dithiolate, L2 = dmid = 1, 3-dithiole-2-one-4, 5-dithiolate, SPh = thiophenolate) (1-4) were characterized by, elemental analysis, ER, UV NMR spectra and so on. The advantages of this method am summarized in two aspects: (1) the preparation is very convenient; (2) the reaction usually completed giving the product with high,purity. The crystal structure of 1 showed that the bond distances of Cd(II) to the sulfur of the thiophenolate group are shorter than those of Cd(II) to the sulfur of dmit, so that the thiophenolate group does not be replaced in the reaction and the mixed ligand complexes are the dominant products. The dmit complexes showed well third-order NLO properties, but not of the dmid complexes, although druid is an analogue to dmit.
  • Preparation and voltammetric characterization of Keggin-type tungstovanadate [VW12O40](3-) and [V(VW11)O-40](4-) complexes, S Himeno, M Takamoto, A Higuchi, M Maekawa, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 348, 57 - 62, May 2003 , Refereed
    Summary:A 12-tungstovanadate complex, [VW12O40](3-) was prepared as the tetrabutylammonium (n-Bu4N+) salt by heating a 50 mM (M = mol dm (-3)) W(VI)-50 mM V(V)-1.5 M HCl-80% (v/v) CH3CN system at 70degreesC for 24 h. The alpha-Keggin structure was confirmed by (15)3W NMR spectroscopy. Besides, the n-Bu4N+ salt of its monovanadium-substituted derivative, [V(VW11)O-40](4-) was also prepared from a 50 mM W(VI)-50 mM V(V)-0.5 M HClO4-50% (v/v) CH3CN system. Both Keggin-type complexes were characterized voltammetrically. A reversible one-electron redox wave due to the central V atom was obtained at potentials more positive than the reduction wave due to the peripheral W atom. Their formation and conversion processes were also elucidated with a combined Raman and voltammetric study. (C) 2002 Elsevier Science B.V. All rights reserved.
  • Thermal transition behavior and crystal structure of octakis(phenylsulfanyl)naphthalene, Y Suenaga, A Ueda, T Kuroda-Sowa, M Maekawa, M Munakata, THERMOCHIMICA ACTA, THERMOCHIMICA ACTA, 400(1-2), 87 - 94, Apr. 2003 , Refereed
    Summary:The conformational properties of octakis(phenylsulfanyl)naphthatene (ophn) were examined by their X-ray structural and thermal analyses. Ophns have been prepared in two different conformations, i.e. the red and yellow forms. The yellow form consists of the aabbaabb and bbaabbaa isomers (the descriptions a and b denote side-chain phenyl moieties projecting above or below, respectively). Both isomers are alternately arrayed in the direction parallel to the c-axis. This crystal structure will not be formed with only the chiral compounds. From the DTA results, the crystal melting point (T-m1) of the red form appeared at around 201.3 degreesC, for the yellow form, T-m2 appeared at around 174.5 degreesC and the crystallization point (T,2) is 114.5 degreesC. Both crystals indicate an amorphous phase during cooling after melting, then the T-g = 60 degreesC. The phase transformation observed for the red and yellow forms is summarized on the basis of the thermal analysis and powder X-ray diffraction pattern. (C) 2002 Elsevier Science B.V. All rights reserved.
  • Construction of the multidecker anthracene-silver(I) system by intramolecular pi-pi interactions, M Munakata, LP Wu, T Kuroda-Sowa, M Maekawa, Y Suenaga, T Ohta, H Konaka, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 42(8), 2553 - 2558, Apr. 2003 , Refereed
    Summary:As a continuation of the study on the construction of the multidecker aromatic compounds with pi-pi interactions, the anthracene derivatives 9,10-dimethylanthracene (dman), 9,10-diphenylanthracene (dpan), and 7,12-dimethylbenz[a]anthracene (dmban) have been studied toward complexation with the silver(l) ion. The crystal structures of [Ag(dman)(0.5)(p-xylene)(ClO4)], [Ag-2(dpan)(0.5)(C6H6)(0.5)(CF3SO3)(2)], and [Ag-2(dmban)(2)(ClO4)(2)](p-xylene), together with the metal-free ligand dpan, have been determined by single-crystal X-ray diffraction. These pi-electron-rich aromatic compounds are found to have great promise as an approach to the effective! self-assembly of high nuclearity in a multilayer fashion.
  • Crystal structure and photo-induced property of two-dimensional silver(I) complex with 1,3,5-tris(benzylsulfanyl)benzene, Y Suenaga, H Konaka, T Sugimoto, T Kuroda-Sowa, M Maekawa, M Munakata, INORGANIC CHEMISTRY COMMUNICATIONS, INORGANIC CHEMISTRY COMMUNICATIONS, 6(4), 389 - 393, Apr. 2003 , Refereed
    Summary:The silver(l) complex [Ag-2(3bsb)(2)(ClO4)(2)] (1) (3bsb; 1,3,5-tris(benzylsulfanyl)benzene) has been prepared and its molecular structure was determined by X-ray crystallography. In 1, the silver ion prefers a tetrahedral coordination geometry and produces a two-dimensional sheet structure containing dimeric units. Irradiation of this complex 1 with light changes its color from white to pink; heat or exposure to acetone vapor makes the irradiated sample revert back to white. However, only 3bsb has no characteristic like this photochromism. (C) 2003 Elsevier Science B.V. All rights reserved.
  • Syntheses and structures of photochromic silver(I) coordination polymers with cis-1,2-dicyano-1,2-bis(2,4,5-trimethyl-3-thienyl)ethene, H Konaka, LP Wu, M Munakata, T Kuroda-Sowa, M Maekawa, Y Suenaga, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 42(6), 1928 - 1934, Mar. 2003 , Refereed
    Summary:Five novel silver(l) coordination polymers with cis-1, 2-dicyano-1,2-bis(2,4,5-trimethyl-3-thienyl)ethene (cis-dbe) were synthesized and are characterized in this paper. Treatment of AgCF3SO3 or AgCF3CO2 with cis-dbe afforded [Ag-2(cis-dbe)(CF3SO3)(2)] (1) and [Ag2(cis-dbe)(CF3CO2)(2)] (2), and both complexes exhibit a 1-D infinite chain structure with two cyano groups and two thienyl groups of the ligand bridging four metal ions. Reaction of AgCnF2n+1CO2 with cis-dbe gave rise to an unprecedented cocrystallization of a 2-D sheet structure, [Ag-2(cis-dbe)(CnF2n+1CO2)(2)], where n = 2 (3), 3 (4), and 4 (5). Upon irradiation with 450 nm light, these five silver(l) complexes turned orange or red from yellow, and the color reverted to yellow on exposure to 560 nm light, indicative of the reversible cyclization/ring-opening reaction occurring in the crystalline phase. Furthermore, different anions gave not only the different structural dimensions but also the different photoresponsive patterns. The correlation between the crystal structures and the photochromic reactivity is discussed.
  • Syntheses and structural characterization of [2.2]paracyclophane complexes of rhodium and iridium supported by diene ligands, M Maekawa, N Hashimoto, K Sugimoto, T Kuroda-Sowa, Y Suenaga, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 344, 143 - 157, Feb. 2003 , Refereed
    Summary:We systematically prepared nine [2.2]paracyclophane complexes of Rh and It, [Rh(eta(6)-PCP)(C2H4)(2)]BF4.THF 1 . THF (pcp = [2.2]paracyclophane),[Rh(il pcp)(diene)]BF4 (diene = 1,5-cyclooctadiene (cod) 2-CH2O2; 2,5-norbornadiene (nbd) 3), [RhAyl, Ti pcp)(diene)(2)](BF4)(2) (diene = cod 4; nbd 5), [Ir(eta(6)-PCP)(cod)]X (X = BF4 6a; ClO4 6b . CH2Cl2) and [Ir-2(eta(6), eta(6)-pcp)(cod)(2)]X-2 (X = BF4 7a; ClO4 7b), seven structures of which were crystallographically characterized. In complexes 1 . THF, 2 . CH2Cl2, 3 and 6b CH2Cl2, each of the Rh or It atoms are eta(6)-bonded to the upper side of the two decks in the pcp ligand to afford a mononuclear structure. The Rh or Ir atoms are supported by ethylene or diene ligands. The average C(pcp)=C(pcp) distance with the Rh or Ir atom of 1.411 (1.THF), 1.413 (2.CH2Cl2), 1.411 (3) and 1.419 Angstrom (6b.CH2Cl2) is longer than those (1.393, 1.393, 1.390 and 1.400 Angstrom) without a Rh or Ir atom, respectively. The average interannular distances between the two decks are 3.03 (1 . THF), 3.01 (2 . CH2Cl2), 3.04 (3) and 3.01 A (6b . CH2O2), respectively. In contrast, in complexes 4, 5 and 7b, two Rh or Ir atoms are eta(6)-coordinated to the upper and lower decks in the pcp ligand to provide a dinuclear structure. The Rh or Ir atoms are similarly supported by diene ligands. Two coordinating cod ligands in pcp complexes 4 and 7b are located in a staggered conformation against the pcp ligand, whereas two nbd ligands in complex 5 are located in an eclipse conformation. The average C(pcp)=C(pcp) distances with the Rh or Ir atom of 1.416 (4), 1.417 (5) and 1.420 Angstrom (7b) are longer than that (1.385 Angstrom) of the metal-free pcp ligand. The average interannular distances between the two decks are 3.04 (4), 3.05 (5) and 3.05 A (7b), respectively. On complexes 1.THF-7b, the average interannular distances of 3.01-3.05 A between the two decks were found to be shorter than that (3.09 A) of the metal-free pcp ligand, suggesting that the repulsive pi-interaction between the two decks is reduced by the coordination of the metal fragment with the diene ligand to the pcp ligand. In addition, the relationships between the intramolecular distances and the configuration of the two ethylenic bridges were quite obvious. If the interannular distance was shorter than 3.05 Angstrom, the configuration of the two ethylenic bridges was more likely a twisted cross type, and if the interannular distance was shorter than 3.01 Angstrom, the configuration was more likely a parallel type, accompanying with the structure conversion of the two ethylenic bridges and the slide of the two decks. In the 1 H NMR study, the stoichiometric 1: 1 reaction solution of [M(diene)](+) (M = Rh and It; diene = cod and nbd) and the pcp ligand in CD2Cl2 or (CD3)(2)CO at 23 degreesC showed two kinds of H-1 NMR signals, which led to assign as a major mononuclear pcp complex [M(eta(6)-pcp)(diene)] (+) and a minor metal-free pcp ligand. On the other hand, the stoichiometric 2:1 reaction solution of [M(diene)](+) and the pcp ligand in CD2Cl2 or (CD3)(2)CO at 23 degreesC revealed two kinds of H-1 NMR signals, which led to assign as a minor dinuclear pcp complex [M-2(eta(6)-pcp)(diene)(2)](2+) and a major mononuclear pcp complex [M(eta(6)-pcp)(diene)](+). These results suggest that the mononuclear pcp complex [M(eta(6)-pcp)(diene)](+) is more stable in solution. (C) 2002 Elsevier Science B.V. All rights reserved.
  • Syntheses and structural studies on silver(I) coordination polymers with trans, trans-1 4-dipenyl-1,3-butadiene, JC Zhong, M Munakata, M Maekawa, T Kuroda-Sowa, Y Suenaga, H Konaka, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 342, 202 - 208, Jan. 2003 , Refereed
    Summary:For the purpose of investigation on the reactivity of silver(l) with multiphenyl diene and the effect of counteranions on silver(l) complexes, we selected several silver(l) salts to react with trans,trans-1,4-diphenyl-1,3-butadiene (dpbd). The treatment of AgClO4.H2O with dpbd afforded a I-D W-type chain silver(l) coordination polymer [Ag(dpbd)(ClO4)] (1) and while the reaction of AgCF3CO2 with dpbd gave rise to a co-crystallization structure [Ag-3(CF3CO2)(3)].(dpbd) (2) in which silver(I) and trifluoroacetate form a 1-D supramolecular ladder chain. The measurements of electric conductivity show that polymer I exhibits semiconductive behavior and while polymer 2 is an insulator. The effect of counteranions and steric hindrance on the formation of these silver(I) complexes is also discussed. (C) 2002 Elsevier Science B.V. All rights reserved.
  • Porous silver(I) organometallic coordination polymer of triptycene, and the guest desorption and absorption, M Wen, M Munakata, Y Suenaga, T Kuroda-Sowa, M Maekawa, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 340, 8 - 14, Nov. 2002 , Refereed
    Summary:On the basis study of porous silver(l) complex of triptycene (tpty), [Ag-3(tpty)(3)(ClO4)(3)](toluene)(2) (1), its toluene desorbed complex (2) and absorbed complex (3) have been synthesized and confirmed by H-1 NMR spectra and X-ray powder diffraction. In complex 1, a 3D architecture with triptycene exhibits an unprecedented mu-eta(2)-eta(2) or mu-eta(2)-eta(2)-eta(1) coordination mode depending on the steric requirements of the network. The desorption and absorption of guest molecules occur in this complex accompanying the structure change. The potential study of these complexes for the rational control and synthesis of porous organometallic coordination network is discussed. (C) 2002 Elsevier Science B.V. All rights reserved.
  • Dinuclear silver(I) complexes of dibenzo-crown ethers and the mononuclear complex of aminobenzo-crown ether, M Wen, M Maekawa, M Munakata, Y Suenaga, T Kuroda-Sowa, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 338, 111 - 118, Oct. 2002 , Refereed
    Summary:Three silver(I) coordination complexes of crown ethers, [Ag([15]C6)(ClO4)(2)](THF) (1), [Ag(DB[21]C7)(H2O)](2)(ClO4)(2) (2) and [Ag(DB[24]C8)(CF3SO3)](2)(acetone)(2) (3) have been synthesized in different solvents and characterized structurally. The mononuclear complex 1 and two different dinuclear complexes 2 and 3 are shown in this work. Silver(l) ions are situated in a distorted pentagonal pyramidal geometry and form close dinuclear complex with DB[21]C7 based on cation-pi interaction in eta(2)-fashion. This coordination unit involves sigma bonding at a part oxygen atoms of ligand oxygen base cavity and pi-pi interaction between two parallel phenyl groups. But in 3, each DB[24]C8 host contained two silver(l) ions as guest without cation-pi and pi-pi interaction. (C) 2002 Elsevier Science B.V.. All rights reserved.
  • Crystal structure of 1 : 1 donor-acceptor complex between 9,10-benzophenanthrene and 2,3,5,6-tetrafluoro-1,4-benzoquinone, JC Zhong, M Maekawa, T Kuroda-Sowa, Y Suenaga, T Ohta, M Munakata, ANALYTICAL SCIENCES, ANALYTICAL SCIENCES, 18(7), 851 - 852, Jul. 2002 , Refereed
  • A chemical modification of a Mn-12 single-molecule magnet by replacing carboxylate anions with diphenylphosphate anions, T Kuroda-Sowa, S Fukuda, S Miyoshi, M Maekawa, M Munakata, H Miyasaka, M Yamashita, CHEMISTRY LETTERS, CHEMISTRY LETTERS, 682-683(7), 682 - 683, Jul. 2002 , Refereed
    Summary:Diphenylphosphate anions can replace with benzoate anions of [Mn12O12(O2CPh)(16)(H2O)(4)] to afford a novel Mn-12 single-molecule magnet (SMM) with mixed bridging ligands.
  • Syntheses and crystal structures of mononuclear rhodium hydrido complexes from the reactions of [Rh(H)(2)(PPh3)(2)(EtOH)(2)]ClO4 with various nitrogen ligands, XY Yu, M Maekawa, T Morita, HC Chang, S Kitagawa, GX Jin, POLYHEDRON, POLYHEDRON, 21(16), 1613 - 1620, Jul. 2002 , Refereed
    Summary:Reactions of the Rh hydrido complex [Rh(H)(2)(PPh3)(2)(EtOH)(2)]ClO4 (1) With nitrogen ligands such as 2-(4-thiazolyl)benzimidazole (tbz). pyridazine (pdz), imidazole (im) and pyrimidine (pmd) in CH,Cl, afforded Various mononuclear Rh hydrido complexes, [Rh(H)(2)(PPh3)(2)(tbz)]CIO4 (2), [Rh(H)(2)(PPh3)(2)(pdZ)(2)]ClO(4)(.)2CH(2)Cl(2) (3). [Rh(H)Cl(PPh3)(2)(pdz)(2)](ClO4CH2Cl2)-C-. (4). [Rh(H)(2)(PPh3)(2)(im)(2)]ClO(4)(.)2CH(2)Cl(2) (5). [Rh(H)Cl(PPh3)(2)(im)(2)](ClO4CH2Cl2)-C-. (6). [Rh(H)(2)(PPh3)(2)(pmd)(2)](ClO4CH2Cl2)-C-. (7) and the Rh non-hydrido complex [RhCl2(pmd)(4)]ClO4 (8). The Rh complexes 2. 3, 5 and 6 were crystallographically characterized. The formation process was monitored by H-1 NMR and UV-Vis spectra. In all the Rh hydrido complexes, the Rh atom is coordinated by two PPh3. ligands in trans-positions and two nitrogen ligands in the cis-positions. The remaining sites Lire occupied by one or two hydride atoms to form a saturated 18-electron framework in a slightly distorted octahedral geometry. For complex 2 an appreciable inter-molecular pi interaction is observed between planes of tbz and PPh3 ligands, while an intra-molecular hydrogen bonding interaction between C-H and Cl atoms is found in complex 6. (C) 2002 Elsevier science Ltd. All rights reserved.
  • Solvent-dependent formation of di- and trinuclear rhodiurn and iridium complexes bridged by N,N '-donor ligands, XY Yu, M Maekawa, T Morita, HC Chang, S Kitagawa, GX Jin, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 75(2), 267 - 275, Feb. 2002 , Refereed
    Summary:Reactions of Rh and Ir hydrido complexes. [Rh(H)(2)(PPh3)(2)(solv)(EtOH)]ClO4 (solv = Me2CO, 1a; EtOH, 1b) and [Ir(H)(2)(PPh3)(2)(Me2CO)(2)]BF4 (2), with various N,N'-donor bridging ligands, such as pyrazine (pyz), 4,4'-trimethylenedipyridine (tmdp) and di(4-pyridyl) disulfide (dpds), in some solvents were examined, and their reaction products were characterized by X-ray crystal structure analysis. IR, H-1 NMR and UV-vis spectra. Rh hydrido complexes, la or 1b, formed a dinuclear Rh complex, [Rh-2(PPh3)(2) {(eta(6)-C6H5PPh2}(2)] (ClO4)(2).6CH(2)Cl(2) (3.6CH(2)Cl(2)), in dichloromethane with a reductive elimination of hydrogen. The reactions of 1a or 1b with the pyz ligand in dichloromethane and tetrahydrofuran gave triangular Rh-3 complexes, [Rh-3(PPh3)(6)(pyz)(3)](ClO4)(3).CH2Cl2 (5.CH2Cl2) and [Rh-3(PPh3)(6)(pyz)(3)](ClO4)(3).EtOH (5.EtOH), respectively, in contrast to the formation of a dinuclear Rh hydrido complex, [Rh-2(H)(4)(PPh3)(4)(Me2CO)(2)(pyz)](ClO4)(2).EtOH A-EtOH). in acetone. The reactions of la or 1b with the tmdp ligand in dichloromethane and 3-methyl-2-butanone also afforded dinuclear Rh complexes, [Rh-2(PPh3)(4)(tmdp)(2)](ClO4)(2) (6) and [Rh-2(PPh3)(4)(tmdp)(2)](ClO4)(2).4MeCOCHMe(2) (6.4MeCOCHMe(2)), respectively. On the other hand, Ir hydrido complex 2 reacted with pyz and dpds ligands in dichloromethane to afford dinuclear Ir complexes, [Ir-2(H)(4)(PPh3)(4)(Me2CO)(2)(pyz)]- (BF4)(2).3CH(2)Cl(2) (7.3CH(2)Cl(2)) and [Ir-2(H)(4)(PPh3)(4)(dpds)(2)](BF4)(2).3CH(2)Cl(2).H2O (8.3CH(2)Cl(2).H2O), respectively, without any reductive elimination of hydrogen. Based on structural studies in solution and in the solid state. it was demonstrated that various Rh and Ir complexes were selectively produced depending on the choice of solvents and N,N'-donor bridging ligands.
  • Benzenthiolate bridged binuclear group 12 metal complexes with TTF fused dithiolate ligand, a new synthetic approach using cluster-cracking reaction, GQ Bian, J Dai, QY Zhu, W Yang, ZM Yan, M Munakata, M Maekawa, CHEMICAL COMMUNICATIONS, CHEMICAL COMMUNICATIONS, 1474-1475(14), 1474 - 1475, 2002 , Refereed
    Summary:Novel binuclear dithiolate complexes (Me4N)(2)[M-2-(SPh)(2)(S2TTF(SMe)(2))(2)] (M = Cd and Zn) have been synthesized by a new cluster-cracking method.
  • Single-molecule magnets: Magnetic properties of [Mn-12] complexes with sulfer-containing carboxylates, T Kuroda-Sowa, T Nogami, M Maekawa, M Munakata, MOLECULAR CRYSTALS AND LIQUID CRYSTALS, MOLECULAR CRYSTALS AND LIQUID CRYSTALS, 379, 179 - 184, 2002 , Refereed
    Summary:Magnetic properties of [Mn-12] complexes with sulfer-containing carboxylates, [Mn12O12(tha)(16)(H2O)(4)] (2) and [Mn12O12(tpc)(16)(H2O)(4)] (3) (thaH = trans-3-(3-thienyl)acrylic acid,. tpcH = 2-thiophenecarboxylic acid), are investigated. Both complexes showed frequency-dependent out-of-phase signals in ac susceptibility, indicating they are single-molecule magnets (SMMs). The energy barrier heights for reversing its magnetization from spin "up" to spin "down" are estimated to be 67 K and 68K for 2 and 3., respectively.
  • Preparation, crystal structures and spectroscopic properties of vanadium(III) complexes with [V-O-V](4+) cores, H Kumagai, S Kitagawa, M Maekawa, S Kawata, H Kiso, M Munakata, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 2390-2396(11), 2390 - 2396, 2002 , Refereed
    Summary:Dinuclear vanadium(III) complexes, [V-2(mu-O)(phen)(4)Cl-2]Cl-2.2Me(2)CO (1) and [V-2(mu-O)(dpya)(4)Cl-2]Cl-2 (2) [phen=1,10-phenanthroline; dpya=bis(2-pyridyl) amine], have been synthesized from the reaction of VCl3 or VCl3(THF)(3) with bidentate nitrogenous ligands. The ligand substitution reaction between NaNCS and 2 yields a brown dinuclear complex, [V-2(mu-O)(dpya)(3)(NCS)(4)].2THF (3), in which each vanadium ion has a different coordination environment, and an orange mononuclear complex, [V(dpya)(NCS)(4)].(Hdpya).THF (4). Complexes 1-3 contain singly bridged [V-O-V](4+) cores. From the temperature dependence of the magnetic susceptibilities, weak magnetic interactions are observed for 1-3. UV-Vis and resonance Raman spectra of these complexes are described. The H-1 NMR spectrum of 1, in which two vanadium ions are coupled antiferromagnetically, and those of its analogs have been measured and assigned.
  • Syntheses and crystal structures of mononuclear [2.2]paracyclophane complexes of rhodium and iridium supported by the pentamethylcyclopentadienyl ligand [M(eta(6)-pcp)(eta(5)-C5Me5)](BF4)(2) (M = Rh and Ir), M Maekawa, N Hashimoto, T Kuroda-Sowa, Y Suenaga, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 328, 254 - 258, Jan. 2002 , Refereed
    Summary:Mononuclear [2.2]paracyclophane complexes of Rh and Ir, [M(eta(6)-pcp)(eta(5)-C5Me5)](BF4)(2) (M = Rh (1) and Ir (2); pcp = [2.2]paracyclophane) were crystallized and their structures were first characterized crystallographically. On both pep complexes the metal atom is bonded to the benzene ring on one side of the pep ligand in the eta(6)-coordination mode. The metal atom is also supported by the eta(5)-C5Me5 ligand to afford a triple-decker sandwich structure. In Rh pep complex I the average Rh-C(pep) and Rh-C(C5Me5) distances are 2.284(2) and 2.161(2) Angstrom, respectively. The average C(pcp) = C(pcp) distance of 1.407(4) Angstrom with the Rh atom is longer than that (1.388(4) Angstrom) without a Rh atom. Similarly, the average Ir-C(pcp) and Ir-C(C5Me5) distances in Ir pcp complex 2 are 2.275(3) and 2.174(3) Angstrom, respectively. The average C(pcp) = C(pcp) distance of 1.410(4) Angstrom with the Ir atom is longer than that (1.388(4) Angstrom) without an Ir atom. It is interesting that the average interannular distances of 2.97 Angstrom for 1 and 2 between two decks of the pep ligand are shorter than that (3.09 Angstrom) of the metal-free pep ligand, indicative of the decrease of the repulsive pi-interaction between benzene rings. The Rh pep complex gave the well-resolved H-1 NMR signals of [Rh(eta(6)-pcp)(n(5)-C5Me5)](2+), whereas the Ir pep complex exhibited two kinds of H-1 NMR signals which were assigned as [Ir(eta(6)-pcp)(eta(5)-C5Me5)](2+) and [Ir-2(eta(6)-pcp)(eta(5)-C5Me5)(2)](4+) in (CD3)(2)CO at 23 degreesC. (C) 2002 Elsevier Science B.V. All rights reserved.
  • A zigzag chain coordination polymer consisting of silver(I) ion having square planar geometry, Y Suenaga, K Kitamura, T Kuroda-Sowa, M Maekawa, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 328, 105 - 110, Jan. 2002 , Refereed
    Summary:Silver(l) complexes of hexakis (tolylsulfanyl) benzene (htsb), [Ag(htsb)](PF6) (1), have been prepared and their molecular structures were determined by X-ray crystallography. In 1, the silver ion prefers a square planar coordination geometry comprized of four S atoms from two different htsb molecules and producing a zigzag chain structure of Ag-S in the silver coordination polymer, Based on the thermo-gravimetry analysis results, two tolylsulfanyl groups were easily eliminated at approximately 211 degreesC. However, [Ag(htsb)(2-butanone)] (PF6) (2), which were obtained by the reactions in different solvents, showed a different colors and thermal degradation behaviors. (C) 2002 Elsevier Science B.V. All rights reserved.
  • Silver(I) coordination polymer of 2,5-bis(4 ',5 '-bis(methylthio)-1 ',3 '-dithiol-2 '-ylidene)-1,3,4,6-tetrathiapentalene (TTM-TTP) and its highly conductive iodine derivative, JC Zhong, Y Misaki, M Munakata, T Kuroda-Sowa, M Maekawa, Y Suenaga, H Konaka, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 40(27), 7096 - +, Dec. 2001 , Refereed
    Summary:The novel silver(I) coordination polymer with 2,5-bis(4',5'-bis(methylthio)-1',3'-dithiol-2'ylidene)-1,3,4,6-tetrathiapentalene (TTM-TTP), [Ag(TTM-TTP)(CF3SO3)](n) (1), which consists of 1-D waving chains, was synthesized and characterized. Polymer 1 can be also regarded as a 3-D supramolecular network formed via many shorter side-by-side and face-to-face (SS)-S-... contacts. This polymer and its iodine-doped compound 2 behave as semiconductors with σ(25&DEG;C) values of 7.1 x 10(-6) and 0.85 S cm(-1), respectively. [GRAPHICS]
  • A double-decker silver(I) coordination polymer of 1-methylpyrene with columnar aromatic stacks. Effect of substituting groups on structure of silver(I) complexes with polycyclic aromatic hydrocarbons, M Munakata, JC Zhong, T Kuroda-Sowa, M Maekawa, Y Suenaga, M Kasahara, H Konaka, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 40(27), 7087 - +, Dec. 2001 , Refereed
    Summary:A novel silver(I) coordination polymer of I-methylpyrene (mpyr) with double-decker motifs, {[Ag-2(mpyr)(2)(ClO4)(2)]0.5benzene}(n) (1), was synthesized and characterized. Polymer I consists of I-D double-decker chains, which are formed by dimeric double-decker units ([Ag(mpyr)(ClO4)](2)) through the linkage of the perchlorate groups. In addition, the dimeric moieties between the adjacent chains are stacked to lead to column π-π stacks. Therefore, complex 1 can also be regarded as a 2-D stacking polymer, The effects of substituting groups, and other factors, on the structure of silver(I) complexes with polycyclic aromatic hydrocarbons are also discussed. [GRAPHICS]
  • A novel derivative of hexathiocane having the 4,5-dimethylthio-1,3-dithiol-2-ylidene moiety, J Dai, MY Zhou, GQ Bian, Wang, X, Qing-Feng, Xu, M Munakata, M Maekawa, JOURNAL OF CHEMICAL RESEARCH-S, JOURNAL OF CHEMICAL RESEARCH-S, 482-484(11), 482 - 484, Nov. 2001 , Refereed
    Summary:An unexpected reaction forming 4,8-bis(4,5-dimethylthio-1,3-dithiol-2-ylidene)-1,2,3,5,6,7-hexathiocane is described.
  • A novel 2-D silver(I)-acyclic polyene coordination polymer assembled with linear unsaturated bridges, JC Zhong, M Munakata, T Kuroda-Sowa, M Maekawa, Y Suenaga, H Konaka, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 322(1-2), 150 - 156, Oct. 2001 , Refereed
    Summary:A novel 2-D silver(I) coordination polymer of 1,8-diphenylocta-1,3,5,7-tetraene was synthesized, and characterized by X-ray single crystal analysis. Reaction of 1,8-diphenylocta-1,3,5,7-tetraene (dpot) with silver(I) perchlorate at 60 degreesC afforded [Ag-2(dPot)(ClO4) (1). In this structure, silver(I) adopts a distorted tetrahedral geometry and the dpot molecules link the silver(I) ions in a trans-mu -tetra-eta (2) manner to generate 1-D chains with metallocyclophane motifs. Further, the silver(I) ions between the two neighboring chains are bridged by perchlorate groups to give a novel 2-D (3,4)-connected polymeric network with (4,6(2))(2)(4(2),6(2),8(2)) topology. Additionally, the main plane of the phenyl moiety makes an angle of 33.08 degrees with the topology through the polyene portion in 1, and thus the coordination of silver(I) to dpot results in the distortion of the dpot molecule. To the best of our knowledge, this is the first example of a silver(I) complex with acyclic polyene. (C) 2001 Elsevier Science B.V. All rights reserved.
  • Silver(I) coordination polymers of cyclic sulfur ligand, 2,2 ',3,3 '-tetrahydro-4,4 '-dithia-1,1 '-binaphthylidene, M Wen, M Munakata, Y Suenaga, T Kuroda-Sowa, M Maekawa, SG Yan, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 322(1-2), 133 - 137, Oct. 2001 , Refereed
    Summary:The silver(I) complexes of 2,2',3,3'-tetrahydro-4,4'-dithia-1,1'-binaphthylidene (ttp) having a nine-member S-Ag-S chelating ring, [Ag(ttp)(ClO4)](n) (1) and [Ag-2(ttp)(2)(CF3SO3)(2)](n) (2), have been synthesized and characterized by single-crystal X-ray diffraction. The ttp is found to offer a potential coordination site for complexation, which can be utilized to generate an interesting array of silver(l) complexes with a one-dimensional chain and a chiral chain. (C) 2001 Elsevier Science B.V. All rights reserved.
  • Carbon and nitrogen coordinated silver(I) polymers of 2,4,6-triphenoxy-1,3,5-triazine, M Munakata, M Wen, Y Suenaga, T Kuroda-Sowa, M Maekawa, M Anahata, POLYHEDRON, POLYHEDRON, 20(18), 2321 - 2327, Aug. 2001 , Refereed
    Summary:For the purpose of furthering the understanding of steric structure effects upon coordination behavior and exploring the possibility of non-planar complexation in the triazine system for formation of extended polymeric structures, 2,4,6-triphenoxy-1,3,5-triazine(tpotz) has been reacted with silver(I) perchlorate and trifluoromethanesulfonate. The crystal structures of [Ag(2)(tpotz)(3)(ClO(4))(2)] and [Ag(2)(tpotz)(2)(CF(3)SO(3))(2)(THF)] have been determined by single-crystal X-ray diffraction. Tpotz is rich in organic components that can offer potential sites for complexation, which can be utilized to generate an interesting array of organometallic compounds with one-dimensional chains. (C) 2001 Elsevier Science Ltd. All rights reserved.
  • A bent two-coordinate silver(I) complex with 2,2 ',3,3 '-tetrahydro-4,4 '-dithia-1,1 '-binaphylidene, M Wen, M Munakata, Y Suenaga, T Kuroda-Sowa, M Maekawa, SG Yan, ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, 57, m246 - m247, Jun. 2001 , Refereed
    Summary:The Ag I complex of 2,2',3,3' -tetrahydro-4,4'-dithia-1,1'-binaphylidene (ttp) has been synthesized and its molecular structure determined as its PF6- salt, i.e. (2,2',3,3'-tetrahydro4,4'-dithia-1,1'--binaphylidene)silver(I) hexafluorophosphate, [Ag(C18H16S2)]PF6. The Ag-I ion has a distorted linear geometry comprised of the two S atoms of ttp, with an Ag-S distance of 2.4889 (8) Angstrom and an S-Ag-S angle of 157.48 (4)degrees; the cation has twofold symmetry. This coordination mode results in the formation of a nine-membered ring.
  • Silver(I) complexes of triazine derivatives having stepped pi-pi interactions and 2D sheets, M Munakata, M Wen, Y Suenaga, T Kuroda-Sowa, M Maekawa, M Anahata, POLYHEDRON, POLYHEDRON, 20(15-16), 2037 - 2043, Jun. 2001 , Refereed
    Summary:Reactions of silver(I) perchlorate and triflate with the triazine ligands 2,4,6-trimethoxy-1,3,5-triazine (L-1) and 2,4,6-triphenyl-1,3,5-triazine (L-2) have provided three novel silver complexes: [Ag(L-1)(2)](ClO4) (1), [Ag(L-1)(2)](CF3SO3) (2) and [Ag-2(L-1)(CF3SO3)(2)] (3). The crystal structures of these complexes have been determined by single-crystal X-ray diffraction. Each complex exhibits distinct coordination behavior and different frameworks. Complex 1 has a 1D stepped framework in which one crystallographically independent metal center interacts with two L-1 molecules and strong pi-pi interactions between the triazine planes of two L-1 molecules exist. On the other hand, complex 2 has a herringbone-like molecular packing in which the triflate ions are arranged between mononuclear complex cations. In complex 3, L-2 molecules are suspended between two double chains of silver triflate through the coordination to silver(I) ions to form the 2D sheet network structure. The factors that influence the crystal structure and packing are discussed. (C) 2001 Elsevier Science Ltd. All rights reserved.
  • Spiral, herringbone, and triple-decker silver(I) complexes of benzopyrene derivatives assembled through eta(2)-coordination, JC Zhong, M Munakata, T Kuroda-Sowa, M Maekawa, Y Suenaga, H Konaka, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 40(13), 3191 - 3199, Jun. 2001 , Refereed
    Summary:Three novel silver(I) complexes with benzopyrene derivatives were synthesized and characterized in this paper. Treatment of AgClO4.H2O with 7-methylbenzo[a] pyrene (L-1) afforded [Ag-2(L-1) (toluene)(0.5)(ClO4)(2)](n) (1) which exhibits a 2-D sheet structure with double-stranded helical motifs. Reaction of AgCF3SO3 with dibenzo[b,def]chrysene (L-2) gave rise to an unprecedented cocrystallization structure, {[Ag-2(L-2)(CF3SO3)(2)][Ag-2(toluene)(2)(CF3SO3)(2)]}(n) (2)1 formed by a 2-D neutral lamellar polymer and a 1 D neutral rodlike one. The ligand benzo[e]pyrene (L-3) coordinated to silver(I) ions generating a closed triple-decker tetranuclear complex [Ag-4(L-3)(4)(p-xylene)(ClO4)(4)] (3) which can be regarded as a stacking polymer owing to existing intermolecular pi-pi stack interactions. The structural diversity of the silver(I) coordination polymers with polycyclic aromatic hydrocarbons is not only related to the stacking patterns of free polycyclic aromatic hydrocarbons in the crystalline state, but also the geometric shapes of the molecules for these free ligands. In addition, the coordination of solvents to metal ions plays a crucial role in the formation of the unprecedented coordination polymeric architectures. The ESR spectroscopic results, conductivity, and synthesis properties are also discussed.
  • 1-D cyano-bridged heterometallic complexes consisting of 1,4,8,11-tetraazacyclotetradecanesilver(II) and tetracyanopalladium(II) or tetracyanoplatinum(II), M Munakata, JC Zhong, Ino, I, T Kuroda-Sowa, M Maekawa, Y Suenaga, N Oiji, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 317(1-2), 268 - 275, May 2001 , Refereed
    Summary:Two unprecedented bimetallic Ag(II) coordination polymers were synthesized and characterized in this paper. Treatment of [Ag(cyclam)](ClO4)(2) and K-2[Pd(CN4)]. 3H(2)O generated [Ag(cyclam)Pd(CN)(2)(mu -CN)(2)](n) (1). Reaction of [Ag(cyclam)](ClO4)(2) with K-2[Pt(CN)(4)]. 3H(2)O afforded [Ag(cyclam)Pt(CN)(2)(mu -CN)(2)](n) (2). The structures of 1 and 2 are similar and consist of 1-D zigzag chains which are linked via intermolecular hydrogen bonding interactions to give rise to 3-D networks. The structural features, IR, ESR and magnetic properties are discussed, respectively. To our knowledge, the complexes reported here are the first example of bimetallic Ag(II) coordination polymers with weak antiferromagnetic spin coupling. The primary results presented here can give an insight into the assembly of Ag(II) coordination polymers. (C) 2001 Elsevier Science B.V. All rights reserved.
  • Syntheses and crystal structures of novel di- and trinuclear rhodium complexes bridged by pyrazine, XY Yu, M Maekawa, M Kondo, S Kitagawa, GX Jin, CHEMISTRY LETTERS, CHEMISTRY LETTERS, 168-169(2), 168 - 169, Feb. 2001 , Refereed
    Summary:Never di- and trinuclear Rh complexes, [Rh-2(PPh3)(4)(H)(4)(Me2CO)(2)(mu -pyz)](ClO4)(2). EtOH and [Rh-3(PPh3),(mu -pyz)(3)](ClO4)(3). EtOH were selectively isolated from the reaction of [Rh(PPh3)(2)(H)(2)(Me2Co)(EtOH)]ClO4 with pyrazine (pyz) in Me2CO and THF, respectively. Their structures were crystallographically characterized.
  • Synthesis of a novel voltammetrically active isopolyoxotungstate anion, [H6W18O60](6-), S Himeno, M Yoshihara, M Maekawa, INORGANIC CHEMISTRY COMMUNICATIONS, INORGANIC CHEMISTRY COMMUNICATIONS, 4(1), 5 - 8, Jan. 2001 , Refereed
    Summary:A novel voltammetrically active isopolyoxotungstate anion, [H6W18O60](6-) was prepared as a tetrapropylammonium (n-Pr4N+) salt from a freshly prepared solution (pH 4.0) of 500 mM (M = mol dm(-3)) W(VI) at ambient temperature. The [H6W18O60](6-) complex was obtained as a transient intermediate in the transformation of [W10O32](4-) into alpha-[H2W12O40](6-), and the formation conditions were elucidated in relation to those of [W10O32](4-) and alpha-[H2W12O40](6-). The [H6W18O60](6-) complex was characterized by W-183 NMR and voltammetric behaviors. (C) 2001 Elsevier Science B.V. All rights reserved.
  • A new method to synthesize unsymmetrical dithiolene metal complexes of 1,3-dithiole-2-thione-4,5-dithiolate for third-order nonlinear optical applications, J Dai, CQ Bian, Wang, X, QF Xu, MY Zhou, M Munakata, M Maekawa, MH Tong, ZR Sun, HP Zeng, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 122(44), 11007 - 11008, Nov. 2000 , Refereed
  • Bridged silver(I) complexes of the polycyclic aromatic compounds tetraphenylethylene and 1,1,4,4-tetraphenyl-1,3-butadiene, Ino, I, LP Wu, M Munakata, T Kuroda-Sowa, M Maekawa, Y Suenaga, R Sakai, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 39(24), 5430 - 5436, Nov. 2000 , Refereed
    Summary:For the purpose of investigating the coordination behavior of the sterically congested alkenes and exploring the possibility of cofacial complexation in the polycyclic aromatic system for formation of extended polymeric networks, tetraphenylethylene (tphe) and 1,1,4,4-tetraphenyl-1,3-butadiene (tphb) have been studied with regard to their complexation with a silver(I) ion. The crystal structures of [Ag(tphe)(ClO4)(p-xylene)], [Ag-2(tphe)(ClO4)(2)], [Ag-4(tphe)(CF3SO3)(4)], [Ag-2(tphb)(ClO4)(2)], and [Ag-2(tphb)(CF3SO3)(2)], together with the metal-free ligands tphe and tphb, have been determined by single-crystal X-ray diffraction. The pi -electron-rich cleft in organic components is found to offer a potential site for complexation, which can be utilized to generate an interesting array of organometallic compounds with one- and two-dimensional frameworks.
  • Structural control of silver(I) coordination polymers: construction of two- and three-dimensional frameworks of silver(I) ions bridged by dicyanopyrazine derivatives, Y Suenaga, T Kamiya, T Kuroda-Sowa, M Maekawa, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 308(1-2), 17 - 21, Oct. 2000 , Refereed
    Summary:The silver(I) complexes of pyrazine-2,3-dicarbonitrile (2,3-dcpz), [Ag(2,3-dcpz)(ClO4)] (1a) and pyrazine-2,5-dicarbonitrile (2,5-dcpz), [Ag(2,5-dcpz)(X)] (2a: X=ClO4, 2b: X = CF3SO3) have been prepared and their molecular structure has been determined by X-ray crystallography. The silver ion in la prefers an octahedral coordination geometry and forms a two-dimensional square mesh structure. On the other hand, the silver ion in both 2a and 2b prefers a distorted square pyramidal coordination geometry that forms a three-dimensional structure with a cavity. By changing the bridging angle of the ligands and the size of the solvent, we could successfully control the crystal structure of the silver(I) coordination polymers. (C) 2000 Elsevier Science S.A. All rights reserved.
  • 2-D interwoven and 3-D 5-fold interpenetrating silver(I) complexes of 1-(isocyanidomethyl)-1H-benzotriazole and 1,3-bis(dicyanomethylidene)indan, Ino, I, JC Zhong, M Munakata, T Kuroda-Sowa, M Maekawa, Y Suenaga, Y Kitamori, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 39(19), 4273 - 4279, Sep. 2000 , Refereed
    Summary:This paper presents novel and distinctive organosilver polymers with intriguing structure motifs, constructed from iodoacetonitrile (L-1), 1-(isocyanidomethyl)-1H-benzotriazole (L-2), 1,3-bis(dicyanomethylidene)indan (L-3), and silver(I) salts, respectively. Treatment of L-1 with AgClO4 generated [Ag(L-1)(ClO4)](n) (1), whose X-ray determination revealed a 2-D wavy sheet structure with square grids. Reaction of L-2 With AgPF6 gave rise to a novel 2-D wavy interwoven network, {[Ag(L-2)(PO2F2)(0.5)](PF6)(0.5)}(n) (2) The complex [Ag-2(L-3)(2)](n) (3) obtained by reaction of AgClO4 with L-3 can be regarded as unprecedented 3-D 5-fold interpenetrating nets with columnar aromatic stacks and indicates semiconductive behavior. The IR, ESR spectroscopic results, conductivities, and structural features of the complexes are discussed, respectively. The present findings may provide insight into the coordination versatility of silver(I) and polynitrile ligands and an inspiration for the self-assembly of novel supramolecular networks with multifunctional ligands. Crystal data: 1, C2H2AgINClO4, orthorhombic, Pca2(1) (No. 29), a = 14.503(1) Angstrom, b = 5.104(2) Angstrom, c = 10.2019(9) Angstrom, Z = 4; 2, C8H6AgN4PF4O, orthorhombic, Pnna (No. 52), a = 12.2705(3) Angstrom, b = 21.150(1) Angstrom, c = 10.040(1) Angstrom, Z= 8; 3, C30H10Ag2N8, triclinic, P (1) over bar (No. 2), a = 14.920(2) Angstrom, b = 11.896(2) Angstrom, c = 7.400(4) Angstrom, alpha = 8.55(2)degrees, beta = 80.87(2)degrees, gamma = 74.47(1)degrees, Z= 2.
  • Structural studies of silver(I) coordination polymers with aryl iodide derived ligands, Ino, I, LP Wu, M Munakata, M Maekawa, Y Suenaga, T Kuroda-Sowa, Y Kitamori, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 39(10), 2146 - 2151, May 2000 , Refereed
    Summary:This paper reports novel silver polymers, built with iodine--silver interactions, with interesting structural motifs. Four silver(I) coordination polymers of the aryl iodide derived ligands, triiodobenzoic acid (HLL), tris(4-iodophenyl)-amine (L-2), and 5,7-diiodo-8-hydroxyquinoline (HL3), have been synthesized and characterized by X-ray crystallography. Treatment of Ag(CH3COO) with HL1 yielded [Ag(L-1)] (1), whose structural analysis revealed 2D layers of ladders connected through weak Ag ... I interaction. Reactions of AgClO4 and L-2 in benzene and nitrobenzene afforded, respectively, two different products, [Ag(L-2)(H2O)]ClO4. C6H6 (2) and [Ag(L-2)(ClO4)] (3). While the structure of 2 could be described as a 2D layer of square and octagons perpendicular to [100], complex 3 is formed by 2D layers of the same topology of 2 (8(2). 4), alternating as ABAB. In contrast, complex 4, [Ag-2(H2L3)(CK3SO3)(3)], obtained by reaction of Ag(CF3SO3) and HL3, was found to consist of a 2D layer based on columnar arrays AgH2L3-Ag(triflate). The solid-state FT-IR and Ag-109 NMR- spectra of theses complexes are discussed on the basis of their crystal structures.
  • A novel trinuclear palladium cluster compound: di-mu(3)-chloro-tris[chloro(triphenylphosphine-P)palladium] acetone solvate, K Sugimoto, T Kuroda-Sowa, SG Yan, M Maekawa, M Munakata, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, 56, 414 - 415, Apr. 2000 , Refereed
    Summary:The title triangular tripalladium cluster, [Pd3Cl5(C18H15P)(3)].- C3H6O, (I), has a trigonal-bipyramidal framework of Pd-3(mu(3)- Cl)(2), with the two Cl atoms in apical positions. Each Pd atom in the framework has two additional coordination sites to establish square-planar cis-PdL2(mu(3)-Cl)(2) geometry. Three P atoms are located on the same side of the plane defined by the Pd-3 triangle, which leads to a pseudo-C-3 nu symmetry for the core framework of Pd-3(mu(3)-Cl)(2)P3Cl3. The average Pd-Cl distance trans to PPh3 is 2.473 (8) Angstrom, which is significantly longer than the average Pd-Cl distance of 2.294 (4) Angstrom for those trans to terminal Cl, due to the strong trans effect of a P atom compared with a Cl atom. Compound (I) has 49 valence electrons and shows a rhombic electron-spin resonance signal, indicating an S = 1/2 ground state.
  • Syntheses, structures, and magnetic properties of Di-mu(3)-chloride-bridged tripalladium compounds, [Pd-3(mu(3)-Cl)(2) (HqnS)(6)]Cl-2 (HqnS = Quinoline-2(1H)-thione) and [Pd-3(mu(3)-Cl)(2)(Et(2)dtc)(2)(PPh3)(2)]center dot C6H6 (Et(2)dtc = N, N '-diethyldithiocarbamate), K Sugimoto, T Kuroda-Sowa, T Goto, M Maekawa, M Munakata, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 73(3), 651 - 655, Mar. 2000 , Refereed
    Summary:Two triangular tripalladium compounds, [Pd-3(mu(3)-Cl)(2)(HqnS)(6)]Cl-2 (1) (HqnS = quinoline-2(1H-thione), and [Pd-3(mu(3)- Cl)(2)(Et(2)dtc)(2)(PPh3)(2)]. C6H6 (2) (Et(2)dtc = N,N'-diethyldithiocarbamate anion), were prepared. Their single crystal X-ray structure analyses revealed they have a similar trigonal bipyramidal framework of Pd-3(mu(3)-Cl)(2) with two chlorine atoms in apical positions. Each Pd atom in all clusters has two additional coordination sites to establish a square planar cis-PdL2(mu(3)-Cl)(2) geometry. In compound 1, six sulfur atoms of six HqnS ligands with thion form are coordinated to the vacant sites of the Pd-3(mu(3)-Cl)(2) core. Two coordination sites of one of the three Pd atoms in 2 are occupied by two triphenylphosphines and those of the other two are coordinated by two S atoms of Et(2)dtc. Although both compounds have 50 valence electrons, only 1 shows paramagnetic behavior. Crystallographic data are as follows. 1: Pd3Cl4S6N6C54H42, triclinic, <P(1)over bar>, a = 14.988(5), b = 17.328(3), c = 12.642(1) Angstrom, alpha = 93.61(1), beta = 96.06(2), gamma = 71.79(2)degrees, V = 3099(1) Angstrom(3), and Z = 2. 2: Pd3Cl2P2S4N2C52H56, monoclinic, P2(1), a = 12.278(5), b = 17.426(6), c = 12.630(3) Angstrom, beta = 94.65(3)degrees, V = 2693(2) Angstrom(3), and Z = 2.
  • Formation of voltammetrically-active isopolyoxotungstate complexes in aqueous CH3CN media, S Himeno, M Yoshihara, M Maekawa, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 298(2), 165 - 171, Feb. 2000 , Refereed
    Summary:A new route to the preparation of voltammetrically-active isopolyoxotungstate complexes was developed by the presence of CH3CN in aqueous W(VI) solutions. In the presence of 40% (v/v) CH3CN as an auxiliary solvent, the [W6O19](2 -) complex was formed in equilibrium with the [W10O32](4 -) complex, which was subsequently transformed into the previously unknown alpha-Keggin-type [H4W12O40](4 -) complex at weaker acidities. The alpha-[H4W12O40](4 -) complex was characterized by voltammetric and spectroscopic behaviors. (C) 2000 Elsevier Science S.A. All rights reserved.
  • A one-dimensional metallocyclophane with columnar aromatic stacking: The silver(I) eta(2)-coordination complex of 1,2-benztriphenylene, M Munakata, GL Ning, Y Suenaga, T Kuroda-Sowa, M Maekawa, T Ohta, ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 39(24), 4555 - +, 2000 , Refereed
  • Three-dimensional silver(I) co-ordination polymer with pocket structures, Y Suenaga, T Kuroda-Sowa, M Maekawa, M Munakata, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 3620-3623(20), 3620 - 3623, 2000 , Refereed
    Summary:Silver(I) complexes of hexakis(phenylsulfanyl)benzene (hphb), [Ag-2(hphb)][PF6](2) 1 and [Ag(hphb)(NO3)] 2, have been prepared and their molecular structures determined by X-ray crystallography. In 1 the silver ion adopts a tetrahedral co-ordination geometry comprising four S atoms from two different hphb molecules and giving an eight-membered Ag-S ring structure in a co-ordination polymer. This ring (6.46 x 6.79 Angstrom) forms a three-dimensional framework with pockets. On the other hand, for 2, the silver(I) ion has a square pyramidal environment with four S atoms and one O atom of a NO3- anion. The complex forms a linear-chain structure with an alternating arrangement of silver ions and hphb.
  • A variety of one-, two- and three-dimensional copper(I) and silver(I) co-ordination polymers assembled by 1,4-bis(4-pyridyl)butadiyne and 1,4-bis(2-pyridyl)butadiyne, M Maekawa, H Konaka, Y Suenaga, T Kuroda-Sowa, M Munakata, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 4160-4166(22), 4160 - 4166, 2000 , Refereed
    Summary:Four copper(I) and six silver(I) novel co-ordination polymers linked by 1,4-bis(4-pyridyl)butadiyne (4-bpbd) or 1,4-bis(2-pyridyl)butadiyne (2-bpbd) were prepared and seven structures crystallographically characterized, in order to illustrate the structural versatility of co-ordination polymers assembled by the Group 11 metal ions and rod-like nitrogen bidentate ligands with long spacers. Reaction of appropriate copper(I) and silver(I) salts with the 4-bpbd ligand affords 2-D interwoven copper(I) co-ordination polymers {[Cu(2)(4-bpbd)(3)(CH(3)CN)(2)]X(2)}(n) (X=PF(6) 1a . 2H(2)O or BF(4) 1b) and 1-D straight chain silver(I) co-ordination polymers {[Ag(4-bpbd)]X}(n) (X=NO(3) 2a . CH(3)CN, ClO(4) 2b . (CH(3))(2)CO or CF(3)SO(3) 2c . (CH(3))(2)CO), respectively. On the other hand, reaction of suitable salts with the 2-bpbd ligand provides a 3-D diamondoid copper(I) co-ordination polymer {[Cu(2-bpbd)(2)]BF(4)}(n) 3b, a 1-D zigzag chain silver(I) co-ordination polymer {[Ag(2-bpbd)(NO(3))]}(n) 4a and a 2-D braid sheet silver(I) co-ordination polymer {[Ag(2-bpbd)(CF(3)SO(3))]}(n) 4c, respectively. On the basis of these structural studies, the unique structural features and the dimensionality of the copper(I) and silver(I) co-ordination polymers are revealed.
  • A variety of one-, two- And three-dimensional copper(i) and silver(i) co-ordination polymers assembled by l,4-bis(4-pyridyl)butadiyne and l,4-bis(2-pyridyl)butadiyne, Masahiko Maekawa, Hisashi Konaka, Yusaku Suenaga, Takayoshi Kuroda-Sowab, Megumu Munakatab, Journal of the Chemical Society, Dalton Transactions, Journal of the Chemical Society, Dalton Transactions, (22), 4160 - 4166, 2000 , Refereed
    Summary:Four copper(i) and six silver(i) novel co-ordination polymers linked by 1,4-bis(4-pyridyl)butadiyne (4-bpbd) or 1,4-bis(2-pyridyl)butadiyne (2-bpbd) were prepared and seven structures crystallographically characterized, in order to illustrate the structural versatility of co-ordination polymers assembled by the Group 11 metal ions and rod-like nitrogen bidentate ligands with long spacers. Reaction of appropriate copper(i) and silver(i) salts with the 4-bpbd ligand affords 2-D interwoven copper(i) co-ordination polymers {[Cu2(4-bpbd)3(CH3CN)2]X2} (X = PF6 la-2H2O or BF4 Ib) and 1-D straight chain silver(i) co-ordination polymers {[Ag(4-bpbd)]X} (X = NO3 2a-CH3CN, C1O4 2b-(CH3)2CO or CF3SO3 2c-(CH3)2CO), respectively. On the other hand, reaction of suitable salts with the 2-bpbd ligand provides a 3-D diamondoid copper(i) co-ordination polymer {[Cu(2-bpbd)2]BF4} 3b, a 1-D zigzag chain silver(i) co-ordination polymer {[Ag(2-bpbd)(NO3)]} 4a and a 2-D braid sheet silver(i) co-ordination polymer {[Ag(2-bpbd)(CF3SO3)]}4c, respectively. On the basis of these structural studies, the unique structural features and the dimensionality of the copper(i) and silver(i) co-ordination polymers are revealed. ©The Royal Society of Chemistry 2000.
  • Syntheses and structures of dinuclear rhodium(I) complexes and 1-D zigzag-chain rhodium(I) co-ordination polymers bridged by rod-like bidentate nitrogen ligands, Masahiko Maekawa, Kunihisa Sugimoto, Takayoshi Kuroda-Sowa, Yusaku Suenaga, Megumu Munakata, Journal of the Chemical Society - Dalton Transactions, Journal of the Chemical Society - Dalton Transactions, (24), 4357 - 4362, Dec. 21 1999 , Refereed
    Summary:Novel dinuclear rhodium(I) complexes, [Rh2(2-bpbd)2(cod)2]X2 (X = BF4 1a, PF6 1b or ClO4 1c cod = cyclo-octa-1,5-diene) and 1-D rhodium(I) co-ordination polymers with the linkage of square-planar rhodium(I) centers, {[Rh(4-bpbd)(cod)]X}n (X = BF4 2a, PF6 2b or ClO4 2c) and {[Rh(4-bpe)(cod)]X}n (X = BF4 3a, PF6 3b or ClO4 3c), were systematically synthesized using 1,4-bis(2-pyridyl)butadiyne (2-bpbd), 1,4-bis(4-pyridyl)butadiyne (4-bpbd) and tran-1,2-bis(4-pyridyl)ethylene (4-bpe). The structures of 1a, 2a, 2b and 3a were crystallographically characterized. In 1a each Rh atom is bridged by two N atoms of 2-bpbd to afford a unique dinuclear structure with an 18-membered Rh2N4C12 framework. In 2a, 2b and 3a, each Rh atom is bonded to two N atoms of 4-bpbd (2a and 2b) or 4-bpe (3a) and two C=C bonds of cod in a square-planar geometry. The square-planar centers are in turn linked by 4-bpbd or 4-bpe ligands to form a 1-D zigzag-chain structure. The zigzag chains are located in parallel 9.6, 9.9 and 10.7 Å apart in 2a, 2b and 3a, respectively, and no effective intermolecular interactions were found. © The Royal Society of Chemistry 1999.
  • Silver(I) complex assemblies with nonplanar aromatic compounds, M Munakata, LP Wu, K Sugimoto, T Kuroda-Sowa, M Maekawa, Y Suenaga, N Maeno, M Fujita, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 38(25), 5674 - 5680, Dec. 1999 , Refereed
    Summary:Reactions of silver(I) perchlorate with the nonplanar aromatic compounds triptycene (L-1), 9,9-bifluorenylidene (L-2), (R)-(+)-1,1-bi-2-naphthol (L-3) and 2,5-norbornadiene (L-4) have isolated four novel hydrocarbon-bridged polymeric complexes: [Ag-3(L-1)(3)(ClO4)(3)]. 2C(6)H(5)Me (1), [Ag-2(L-2)(2)(ClO4)(2)]. C6H4Me2 (2), [Ag-2(L-3)(C6H6)(2)(ClO4)(2)] (3), and [Ag(L-4)(ClO4)] (4). Structural studies using single-crystal X-ray diffraction have shown that all compounds contain extended two- or three-dimensional structures based on cation-rr interactions. While complex 1 in the solid stale contains a three-dimensional architecture in which die triangular molecule triptycene exhibits an unprecedented mu-eta(2)-eta(2) or mu-eta(2)-eta(2)-eta(1) coordination mode depending on the steric requirements of the network, 3 represents the first example of pi coordination of naphthol-containing micropores in its metal complexes. Infinite chains consisting of alternating silver ions and hydrocarbon molecules observed in both 2 and 4 are linked together by perchlorates, affording 2-D frameworks. The potential use of these pi complexes for the rational control and synthesis of polymeric organometallic materials is discussed. Crystal data: 1, C74H58Ag3Cl3O12, monoclinic, Cc, a = 37.951(4) Angstrom, b = 8.047(4) Angstrom, c = 20.882(5) Angstrom, beta = 93.72(1)degrees, V= 6365(3) Angstrom(3), Z = 4; 2, C60H42Ag2Cl2O8. monoclinic, P2(1)/n, a = 12.317(4) Angstrom, b = 7.961(1) Angstrom, c = 24.741(1) Angstrom, beta = 100.015(1)degrees, V = 2389(6) Angstrom(3) , Z = 2; 3, C32H26Ag2Cl2O10, tetragonal, P4(1)2(1)2, a = 8.759(6) Angstrom, c = 39.967(8) Angstrom V= 3065(3) Angstrom(3), Z = 4; 4, C7H8-AgClO4 monoclinic, p2(1)/n, a = 9.847(4) Angstrom, b = 9.0543 Angstrom, c = 10.662(3) Angstrom, beta = 106.72(2)degrees, V= 910.3(4) Angstrom(3), Z = 4.
  • Mobility of silver(I) ions around the propeller ligand, hexaphenylbenzene (HPB), in silver(I) pi-complexes, GL Ning, M Munakata, LP Wu, M Maekawa, Y Suenaga, T Kuroda-Sowa, K Sugimoto, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 38(25), 5668 - 5673, Dec. 1999 , Refereed
    Summary:This paper describes three novel and distinctive organosilver(I) complexes with propeller ligand, hexaphenylbenzene (HPB), whose structures are controlled by selected solvents and anions. Treatment of HPB with AgClO4 and AgCF3SO3 in toluene gave, complexes [Ag-4(HPB)(ClO4)(4)] 1 and [Ag-2(HPB)(CF3SO3)(2)(toluene)] 2, respectively. The single-crystal X-ray analysis revealed that 1 contains 2-D sheet framework whereas 2 consists of l-D chain structure. In both complexes the anions play the role of linkers instead of spacers in the construction of polymeric structures. In contrast, complex [Ag-2(HPB)(ClO4)(2)(THF)(2)] 3, obtained by using tetrahydrofuran (THF) ill place of toluene in the synthetic process of 1, exhibits a discrete dimer. The fundamentals of the synthesis of these complexes, influences of anions and solvents on their coordination networks, and physicochemical properties are discussed. The present findings may serve as a basis for understanding the construction of solid-state materials with designed architecture in crystal engineering. Crystallographic data are as follows. 1: C21H15Ag2Cl2O8, monoclinic, P2(1)/c, a = 10.543(2) Angstrom, b = 11.934(4) Angstrom, c = 16.224(3) Angstrom, beta = 94.08(2)degrees, Z = 4. 2: C51H38-Ag2S2F6O6, monoclinic, C2/c, a = 18.200(4) Angstrom, b = 16.831(7) Angstrom, c = 16.244(3) Angstrom, beta = 110.96(2)degrees, Z = 8. 3: C25H23AgClO5, monoclinic, P2(1)/c, a = 11.321(3) Angstrom, b = 12.511(4) Angstrom, c = 16.357(3) Angstrom, beta = 99.98(2)degrees, Z = 4.
  • Syntheses and structures of dinuclear rhodium(I) complexes and 1-D zigzag-chain rhodium(I) co-ordination polymers bridged by rod-like bidentate nitrogen ligands, M Maekawa, K Sugimoto, T Kuroda-Sowa, Y Suenaga, M Munakata, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 4357-4362.(24), 4357 - 4362, Dec. 1999 , Refereed
    Summary:Novel dinuclear rhodium(I) complexes, [Rh(2)(2-bpbd)(2)(cod)(2)]X(2) (X=BF(4) 1a, PF(6) 1b or ClO(4) 1c; cod=cycloocta-1,5-diene) and 1-D rhodium(I) co-ordination polymers with the linkage of square-planar rhodium(I) centers, {[Rh(4-bpbd)(cod)]X}(n)(X=BF(4) 2a, PF(6) 2b or ClO(4) 2c) and {[Rh(4-bpe)(cod)]X}(n) (X=BF(4) 3a, PF(6) 3b or ClO(4) 3c), were systematically synthesized using 1,4-bis(2-pyridyl)butadiyne (2-bpbd), 1,4-bis(4-pyridyl)butadiyne (4-bpbd) and trans-1,2-bis(4-pyridyl)ethylene (4-bpe). The structures of 1a, 2a, 2b and 3a were crystallographically characterized. In 1a each Rh atom is bridged by two N atoms of 2-bpbd to afford a unique dinuclear structure with an 18-membered Rh(2)N(4)C(12) framework. In 2a, 2b and 3a, each Rh atom is bonded to two N atoms of 4-bpbd (2a and 2b) or 4-bpe (3a) and two C=C bonds of cod in a square-planar geometry. The square-planar centers are in turn linked by 4-bpbd or 4-bpe ligands to form a 1-D zigzag-chain structure. The zigzag chains are located in parallel 9.6, 9.9 and 10.7 Angstrom apart in 2a, 2b and 3a, respectively, and no effective intermolecular interactions were found.
  • A linear-chain silver(I) coordination polymer with tetrakis (isopropylthio)-p-benzoquinone, Y Suenaga, T Kuroda-Sowa, M Maekawa, M Munakata, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, 55, 1623 - 1625, Oct. 1999 , Refereed
    Summary:The silver(I) complex of tetrakis(isopropylthio)-p-benzoquinone (tpq), catena-poly [silver(I)-mu-[2,3,5,6-tetrakis (isopropylthio)-p-benzoquinone-S-2,S-3:S-5,S-6]] perchlorate acetone solvate, {[Ag(C18H28S4O2)]ClO4. C3H6O}(n), has been prepared and the molecular structure determined. The silver ion prefers a tetrahedral coordination geometry comprising four S atoms from two different tpq molecules, giving a linear-chain structure of alternating metal cations and organic ligands. Also, the four isopropyl groups of the tpq molecule lie in the perpendicular direction of the plane of the benzoquinone ring.
  • Syntheses, crystal structures and autoreduction behavior of antiferromagnetically coupled dicopper(II) oximato complexes, M Maekawa, S Kitagawa, Y Nakao, S Sakamoto, A Yatani, W Mori, S Kashino, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 293(1), 20 - 29, Oct. 1999 , Refereed
    Summary:Four dicopper(II) oximato complexes of 2-[2-(alpha-pyridyl)methyl]imino-3-butanone oxime (pmiboH) and 2-[2-(alpha-pyridyl)ethyl]imino-3-butanone oxime (peiboH), [Cu-2(pmibo)(2)](ClO4)(2) (1), [Cu-2(pmibo)(2)](NO3)(2). CH3OH, (2), [Cu-2(peibo)(2)](ClO4)(2). CH3OH (3) and [Cu-2(peibo)(2)(H2O)(2)](ClO4)(2) (4), were prepared and characterized structurally and magnetically. All the dicopper(II) oximato complexes have a common cationic structure in which the two Cu atoms are bridged through two N-O bridges of the oximato ligand to afford a dinuclear structure. The cation moieties of 1 and 2 consist of one six-membered Cu2N2O2 chelate ring and four five-membered (CuN2C2 and CuNC2N) chelate rings, providing a planar configuration. The cation moieties of 3 and 4 are also composed of three six-membered (Cu2N2O2 and CuNC3N) chelate rings and two five-membered CuN2C2 chelate rings, giving a twisted-boat configuration. The -2J values (H = -2JS(1)S(2)) are 835, 825, 550 and 510 cm(-1) for 1, 2, 3 and 4, respectively, indicative of a strong antiferromagnetic interaction in the solid state. All the dicopper(II) oximato complexes show seven H-1 NMR signals at 23 degrees C in the range of -0.5 to 30 ppm with the linewidths at half-height, Delta v(1/2) of 60-1500 Hz, which is characteristic of antiferromagnetic species and indicates that the dinuclear structure is kept in solution. The -2J values reflect the degree of distortion from the planarity of the Cu-2 framework. The -2J values roughly correlate with the H-1 NMR parameters; the larger the -2J values, the smaller the chemical shifts and linewidths. Complexes 1 and 2 were found to undergo an autoreduction reaction in dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF) and N,N-dimethylacetamide (DMA), and their behaviors were first monitored by UV-Vis and H-1 NMR methods. (C) 1999 Elsevier Science S.A. All rights reserved.
  • Two-dimensional supramolecular co-ordination compounds of silver(I) with box structures, Y Suenaga, T Kuroda-Sowa, M Maekawa, M Munakata, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 2737-2741.(16), 2737 - 2741, Aug. 1999 , Refereed
    Summary:Silver(I) complexes of 2,3,5,6-tetrakis(methylsulfanyl)pyridine (tmp), [Ag-3(tmp)(4)][ClO4](3). C3H6O 1 and [Ag-2(tmp)(2)][C2F5CO2](2) 2, have been prepared and their molecular structures determined by X-ray crystallography. In both complexes two tmp ligands are positioned face to face by two Ag atoms and form a box structure. In 1 three types of silver(I) ion are present depending on the co-ordination numbers. One tmp molecule acts as a bridge between box structures leading to a tape arrangement. The pi-pi stackings between pyridine rings give a two-dimensional network. In 2, by contrast, the silver(I) ion has a trigonal planar environment with three thioether S atoms; each tmp acts as a ligand bridging metal centres resulting in a two-dimensional sheet.
  • A novel double-strand helical motif in a two-dimensional polymeric complex of silver(I) perchlorate with benzo[e]acephenanthrylene, M Munakata, GL Ning, Y Suenaga, K Sugimoto, T Kuroda-Sowa, M Maekawa, CHEMICAL COMMUNICATIONS, CHEMICAL COMMUNICATIONS, 1545-1546.(16), 1545 - 1546, Aug. 1999 , Refereed
    Summary:A 2-D double-strand helical complex with a strand of polycyclic aromatic hydrocarbons and a strand of silver(I) perchlorate has been isolated and crystallographically characterised.
  • Construction of 2-D multilayer structures: silver(I) complexes with linear aromatic compounds, GL Ning, LP Wu, K Sugimoto, M Munakata, T Kuroda-Sowa, M Maekawa, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 2529-2536.(15), 2529 - 2536, Aug. 1999 , Refereed
    Summary:For the purpose of exploring the structural relations of organometallic compounds to their organic components, a series of linear polycyclic aromatic hydrocarbons (PAHs) benzo[a]phenanthrene (L-1), dibenz[a,h]anthracene (L-2), benz[a]anthracene (L-3), and naphtho[2,3- a]pyrene (L-4), have been studied towards complexation with silver(I) ion. The crystal structures of [Ag-3(L-1)(ClO4)(3)(H2O)(2)] 1, [Ag-2(L-2)(ClO4)(2)] 2, [Ag-2(L-3)(ClO4)(2)(H2O)] 3, and [Ag-2(L-4)(CF3SO3)(2)] 4 have been determined by single-crystal X-ray diffraction. Although each of these complexes exhibits distinct co-ordination behavior and different frameworks, all of them retain or partially keep the herringbone-packing pattern of their metal-free aromatic ligands in the crystalline state, and display similar two-dimensional multilayer architectures on a given plane. The fundamentals of the synthesis, possible formation mechanism of these polymeric networks and some properties are discussed.
  • Silver(I) tetraiodoethylene complexes with twisted olefin moiety, LP Wu, M Munakata, T Kuroda-Sowa, M Maekawa, Y Suenaga, Y Kitamori, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 290(2), 251 - 255, Jul. 1999 , Refereed
    Summary:The reactions of silver perchlorate and tetraiodoethylene in different solvents, namely, benzene and toluene, isolated two silver(I)-iodocarbon complexes, [Ag(C2I4)(C6H6)(2)(ClO4)] (1) and [Ag(C2I4)(ClO4)] (2). Both compounds contain intact iodoalkenes which coordinate via sigma-donation of a halogen lone pair and retain their carbon-iodine bonds. Owing to the participation of the benzene molecules in coordination, complex 1 is found to be a discrete monomer in which the five-coordinate geometry of the silver ion is comprised of two benzene molecules, one C2I4 group and one perchlorate ion. In contrast, the unsaturated coordination environment of the metal ion in 2 is filled by the second iodocarbon group leading to a two-dimensional framework. The coordinated tetraiodoethylene molecules involve severe twisting of the C=C double bond, causing the C=C stretching band to move to a lower frequency. (C) 1999 Elsevier Science S.A. All rights reserved.
  • Construction of metal sandwich systems derived from assembly of silver(I) complexes with polycyclic aromatic compounds, M Munakata, LP Wu, GL Ning, T Kuroda-Sowa, M Maekawa, Y Suenaga, N Maeno, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 121(21), 4968 - 4976, Jun. 1999 , Refereed
    Summary:A new class of metal sandwich complexes of silver derived from silver(I) perchlorate and fluoranthene (L-1), benzo[ghi]perylene (L-2), [2,2]paracyclophane (L-3), and decacyclene (L-4) was prepared. The idea behind the use of polycyclic aromatic compounds as an alternative approach for construction of organometallic sandwich systems is to combine the plasticity of the metal ion and planarity and coordinative diversity of the hydrocarbons. Structural studies by single-crystal X-ray diffraction have shown that all compounds contain extended one- to three-dimensional structures in which several metal atoms are sandwiched between two fused polycyclic systems. While complex 1, [Ag-3(L-1)(2)(ClO4)(3)], exists in the solid state as a two-dimensional W-type architecture in which AgClO4 layers are separated by two sheets of hydrocarbon, complex 2, [Ag(L-2)(ClO4)](4). toluene, contains two double-decker polymeric chains coupled via extensive aromatic pi-pi stackings. Pillared brick sandwiched framework was observed in 3, [Ag(L-3)(ClO4)], whereas the multidecker sandwich complex 4, [Ag-2(L-3)(ClO4)(2)(benzene)], is reminiscent of ladder. The structure of L-1 has been redetermined and that of L-2 reported; the structural data are used for discussion of the silver-pi interactions. The electrochemical behavior and ESR spectra are consistent with formation of the organic radical species in the system. The present findings may represent an alternative approach for predesigning the multilayered systems in organometallic chemistry.
  • Cationic tetrasilver complex of hexaphenylbenzene, GL Ning, M Munakata, LP Wu, M Maekawa, T Kuroda-Sowa, Y Suenaga, K Sugimoto, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 38(7), 1376 - +, Apr. 1999 , Refereed
    Summary:A silver(I) compound with the propeller ligand hexaphenylbenzene has been synthesized, which shows the high degree of silver ions ordering around the peripheral rings of each propeller, forming a 2-D sheet framework.
  • Open dimeric and capped polymeric container molecules: calixarene and resorcinarene complexes of Ag-I co-ordinated by participation of the upper-rim carbon atoms, M Munakata, LP Wu, T Kuroda-Sowa, M Maekawa, Y Suenaga, K Sugimoto, Ino, I, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 373-378.(3), 373 - 378, Feb. 1999 , Refereed
    Summary:The reactions of C-methylcalix[4]resorcinarene (L-1), calix[6]arene (L-2) and calix[4]arene (L-3) With silver(I) salts have resulted in the isolation and structural characterization of three dimeric and one polymeric silver derivatives of calixarene based on cati on pi interactions. The dinuclear cation in [Ag-2(L-1)(C6H6)(2)][ClO4](2). 5C(4)H(8)O 1 contains two symmetry-related metal centers, each involving a rather distorted tetrahedral co-ordination with, in addition to one benzene molecule, both the aryl OH groups and the aromatic rings of resorcinarene. The two dimeric calix[6]arene structures, {[Ag(L-2)X]. 2C(6)H(6)}(2,) where X = ClO4- 2 or CF3SO3- 3, display similar characteristics with two ligand groups inversely linked by the co-ordination of the silver ion to the phenyl carbons. The solvent molecules or the counter anions are not included in the cavity generated by the dimeric unit, but intercalated into calixarene or resorcinarene bilayers. In the calix[4]arene complex [Ag-2(L-3)(ClO4)(2)] 4 each of the four phenyl rings is bound to one metal atom which in turn bridges between the two calixarenes leading to an infinite two-dimensional arrangement. The polyoxo anion bridging between silver ions partially caps the container cavity of the calixarene. The factors controlling the selectivity of complexation and inclusion properties of calixarenes are discussed.
  • Syntheses and structures of copper(I) and silver(I) coordination polymer with hexakis(methylthio)benzene, Y Suenaga, T Kuroda-Sowa, M Munakata, M Maekawa, H Morimoto, POLYHEDRON, POLYHEDRON, 18(3-4), 429 - 436, 1999 , Refereed
    Summary:Copper(I) and silver(I) complexes of hexakis(methylthio)-benzene (hmb), [Cu(hmb)]PF6 (1) and [Ag(hmb)]PF6 (2), have been prepared and their molecular structures determined by X-ray crystallography. In 1 the copper ion prefers a tetrahedral coordination geometry comprising four sulfur atoms from two different hmb molecules and giving a linear chain structure of alternating metal cations and organic ligands. The para-position two sulfur atoms of hmb are not coordinated to copper. In 2 silver ion is of similar coordination geometry to copper ion but the shortest S ... S distance between inter-chain S atoms no coordinated with silver is 3.57 Angstrom. Therefore. complex 2 forms two-dimensional network through S ... S contacts. (C) 1998 Elsevier Science Ltd. All rights reserved.
  • A linear-chain copper(I) coordination polymer with hexakis(methylthio)benzene, Y Suenaga, T Kuroda-Sowa, M Munakata, M Maekawa, H Morimoto, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, 54, 1566 - 1569, Nov. 1998 , Refereed
    Summary:In the structure of catena-poly [copper(I)-mu-[hexakis(methylthio)benzene-S-1,S-2:S-4,S-5]] hexafluorophosphate, {[Cu(C12H18S6)]PF6}(n), each Cu atom is coordinated to four S atoms of two hexakis(methylthio)benzene ligands in a tetrahedral arrangement to give a cationic linear-chain polymer. The electrical resistivity of compacted pellets was measured by the conventional two-probe technique. Iodine-doped black products in powder form behave as a semiconductor with a conductivity of 1.5 x 10(-6) S cm(-1).
  • Construction of copper(I) coordination polymers of 1,2,4,5-tetracyanobenzene with zigzag sheet and porous frameworks, M Munakata, GL Ning, T Kuroda-Sowa, M Maekawa, Y Suenaga, T Horino, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 37(21), 5651 - 5656, Oct. 1998 , Refereed
    Summary:This paper describes two copper(I) supramolecules with the same anion and cation but quite different topologies and properties. The reaction of [Cu(CH3CN)(4)]PF6 and 1,2,4,5-tetracyanobenzene (TCNB) leads to two novel polymeric coordination compounds, [Cu-2(TCNB)(3)](PF6)(2)(Me2CO)(4) (1) and [CU2(TCNB)(3)](PF6)(2) (2), depending on the solvents used. The crystal structures have been determined by single-crystal X-ray diffraction. Crystal data are as follows, 1: C21H15N6O2CuPF6, monoclinic, P2(1)/a, a = 11.553(4) Angstrom, b = 16.135(7) Angstrom, c = 15.046(3) Angstrom, beta = 108.08(2)degrees, Z = 4. 2: C15H3N6CuPF6, orthorhombic, Cmcm, a = 28.282(3) Angstrom, b =10.337(3) Angstrom, c = 16.285(4) Angstrom, Z = 16. In both polymers, copper(I) ions have similar pseudotetrahedral environments and the four coordination sites are fully occupied by the four bridging ligands, two mu(2)-TCNB and two mu(4)-TCNB groups. Polymer 1, obtained in acetone, revealed a two-dimensional zigzag sheet network between copper(I) ions, whereas 2, synthesized in methylethyl ketone, displayed a three-dimensional porous framework with different functional groups (or atom) in different cavities. The redox, magnetic, and conductive behaviors of both complexes are discussed. It is demonstrated that the two complexes give different physicochemical properties.
  • Supramolecular silver(I) complexes with highly strained polycyclic aromatic compounds, M Munakata, LP Wu, T Kuroda-Sowa, M Maekawa, Y Suenaga, GL Ning, T Kojima, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 120(34), 8610 - 8618, Sep. 1998 , Refereed
    Summary:Four organosilver(I) complexes of polycyclic aromatic hydrocarbons (PAHs) have been investigated crystallographically. The aim was to establish whether a favorable combination of cation-pi interactions and aromatic stackings might produce functional organometallic solid materials with novel networks. Complete structures of the silver(I) perchlorate with 9,10-diphenylanthracene (L-1), rubrene (L-2), benzo[a]pyrene (L-3), and coronene (L-4) were determined by X-ray diffraction. All compounds are organometallic species based on cation-pi interactions. While complex 1 with L-1 revealed a discrete mononuclear structure, complex 2 with rubrene displayed a ct-bonded 3-D polymer. Complexes 3 and 4 can be regarded as both coordination polymer and stacking polymer, and the detailed differences in the geometries and the stacking patterns of 1,3 and L-4 gave helical and triple-decker networks, respectively. The ESR spectroscopic results and conductivity of the compounds are also discussed. The present findings may serve as a basis for understanding specific interactions responsible for self-assembly of multinuclear aggregates involving PAHs.
  • A novel two-dimensional copper(I) coordination polymer with bridging TTF: Crystal structure of [Cu(dmtpn)(2)(TTF)(0.5)](ClO4)(dmtpn: 2,5-dimethylterephthalonitrile), T Kuroda-Sowa, M Hirata, M Munakata, M Maekawa, CHEMISTRY LETTERS, CHEMISTRY LETTERS, 499(6), 499 - 500, Jun. 1998 , Refereed
    Summary:The X-ray crystal structure analysis of a copper(I) coordination compound, [Cu(dmtpn)(2)(TTF)(0.5)](ClO4) revealed the novel two-dimensional polymer framework bridged by dmtpn and TTF, which is the first example of bridging TTF coordinated. to transition metal ions.
  • Dicopper complexes derived from 4-amino-2,1,3-benzothiadiazole with versatile co-ordination number and geometry, M Munakata, HY He, T Kuroda-Sowa, M Maekawa, Y Suenaga, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 1499(9), 1499 - 1502, May 1998 , Refereed
    Summary:Three dicopper complexes of 4-amino-2,1,3-benzothiadiazole (abt) have been isolated and structurally characterized. The reaction of [Cu(CH3CN)(4)][PF6] with abt in THF produced [Cu-2(abt)(2)(CH3CN)(4)][PF6](2) . C6H12 1 . C6H12, while in acetone, Cu-I template Schiff-base condensation of the amino group of abt with solvent was found to give [Cu-2(ibt)(2)(CH3CN)(4)][PF6](2) 2 (ibt = 4-isopropylideneamino-2,1,3-benzothiadiazole). In complex 1 there are two crystallographically independent monomeric units in each of which Cu-I is co-ordinated by one N atom on the ring of abt and two acetonitrile molecules; two units are linked to each other by weak binding of the amino group of abt with Cu-I to give a cyclic dinuclear complex. In complex 2 tetrahedral Cu-I centers are bridged by two ibt molecules in a head-to-tail fashion as in 1. Both 1 and 2 have the same metallocyclophane skeletons showing an intramolecular stacking interaction between two parallel aromatic rings and a considerably long Cu ... Cu separation [7.220(5) Angstrom for 1, 6.542(4) Angstrom for 2]. Following the same synthetic strategy as used for the synthesis of 2 another dicopper complex [Cu-2(ibt)(2)][ClO4](2) 3 was obtained, which presents a structural contrast with 2: two Cu-I centers are linearly co-ordinated by two ibt molecules in a head-to-head arrangement which leads to a twisted conformation with a shorter Cu ... Cu distance of 2.699(2) Angstrom. In addition, H-1 NMR measurements reveal that 2 can also be formed directly from 1 in acetone solution.
  • Synthesis and structure of a novel bis (mu-eta(2)-thianthrene) disilver(I) bis (perchlorate), M Munakata, SG Yan, Ino, I, T Kuroda-Sowa, M Maekawa, Y Suenaga, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 271(1-2), 145 - 150, Apr. 1998 , Refereed
    Summary:A novel bis(thianthrene)disilver(I)bis(perchlorate), [Ag-2(TA)(2)(ClO4)(2)] (1) (TA = thianthrene), was prepared and characterized by single-crystal X-ray diffraction methods, H-1 and C-13 NMR: IR and UV spectra analysis. Complex 1 is triclinic, space group <P(1)over bar>, a = 9.244(1), b = 9.275(1), c = 8.343(2) Angstrom, alpha = 101.22(1)degrees, beta = 110.63(1)degrees, gamma = 97.15(i)degrees, V = 679.8(2) Angstrom(3), Z = 2, R = 0.028 and R-w = 0.042. The silver is tetrahedrally coordinated to an oxygen of ClO4-, a phenylene ring of one TA, and to two sulfur atoms of the other TA. The average distance of silver to the phenylene ring in complex 1 is 2.55 Angstrom. Both H-1 and C-13 NMR Studies indicate that the silver-phenylene ring bond is broken in acetone solution. The complex 1 is an insulator, while the I-2-doped blue complex shows a new absorption band at 478 nm and an electric conductivity of 5.0 x 10(-4) S cm(-1). (C) 1998 Elsevier Science S.A.
  • Synthesis and crystal structure of two ternary dicopper(I) complexes having the unsymmetrical coordination arrangement bridged by 1,8-naphthyridine (napy). [Cu-2(napy)(2)(Me2CO)](PF6)(2)center dot 2Me(2)CO and [Cu-2(napy)(2)(dppm)(CH3CN)](PF6)(2), M Maekawa, M Munakata, S Kitagawa, T Kuroda-Sowa, Y Suenaga, M Yamamoto, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 271(1-2), 129 - 136, Apr. 1998 , Refereed
    Summary:Two novel ternary dicopper(I) complexes bridged by 1,8-naphthyridine (napy), [Cu-2(napy)(2)(Me2CO)](PF6)(2) . 2Me(2)CO (1) and [Cu-2(napy)(2)(dppm) (CH3CN)] (PF6)(2) (2), have been prepared and their structures have been determined crystallographically. Complex 1: space group P2(1)/a, a = 12.281(4), b = 21.154(3), c = 13.891(3) Angstrom, beta = 112.74(2)degrees, Z= 4, R = 0.079 and R-w = 0.093. Complex 2: space group Cc, a = 19.572(7), b = 13.708(7), c = 18.457(3) Angstrom, beta= 108.56(2)degrees, Z= 4, R= 0.064 and R-w = 0.066. On complex 1 two Cu atoms are doubly bridged by two napy ligands to provide a dinuclear structure, which has a close Cu(I)... Cu(I) separation of 2.533(2) Angstrom. Two Cu atoms on 2 are also triply bridged by two napy and one dppm ligands to give a dinuclear structure with a close Cu(I)... Cu(I) separation of 2.607(3) Angstrom On these dicopper(I) complexes the most remarkably structural feature is that the coordination environment around each Cu atom is different: complex 1 has one linear and one T-shaped copper, and 2 has one distorted trigonal and one distorted tetrahedral copper. It was structurally found that the Cu(I)Cu(I) separation greatly depends on the coordination arrangement around each Cu atom: the Cu(I)... Cu(I) distance should be longer in the order of the coordination arrangements of {two linear coppers}, {one linear and one T-shaped copper}, {two trigonal coppers}, {one trigonal and one tetrahedral copper}, and {two tetrahedral coppers}. (C) 1998 Elsevier Science S.A.
  • Self-assembly of copper(I) and silver(I) complexes with square-grid and channel structures, Y Suenaga, SG Yan, LP Wu, Ino, I, T Kuroda-Sowa, M Maekawa, M Munakata, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 1121(7), 1121 - 1125, Apr. 1998 , Refereed
    Summary:Copper(I) and silver(I) complexes of 2-[bis(methylsulfanyl)methylene]propanedinitrilel (bmmp), [Cu(bmmp)(2)]ClO(4) 1 and [Ag(bmmp)(2)]ClO(4) 2, have been prepared and their molecular structures determined by X-ray crystallography. The network topology of bmmp is found to depend on the metal-ion stereochemical preference. In 1 the copper(I) ion prefers a tetrahedral co-ordination geometry comprising four nitrogen atoms from four different bmmp molecules and each bmmp in turn bridges two copper(I) centres leading to a square-grid arrangement of alternating metal cations and organic ligands. In 2, by contrast, the silver(I) ion involves an elongated octahedral environment with four N atoms forming a basal plane and two thioether S atoms occupying the axial positions; each bmmp acts as a non-chelating tridentate ligand bridging three metal centres, resulting in a three-dimensional channel structure. The influence of the metal-ion stereochemical preference on the co-ordination networks of bmmp is discussed.
  • Crystal structure of bis(diphenylphosphino)methane dipalladium(I) nitrate complex, [Pd-2(mu-dppm)(2)(NO3)(2)], M Maekawa, M Munakata, T Kuroda-Sowa, Y Suenaga, ANALYTICAL SCIENCES, ANALYTICAL SCIENCES, 14(2), 447 - 449, Apr. 1998 , Refereed
  • Assembly of a mixed-valence Cu(I/II) system coupled by multiple hydrogen bonding through tetrahydroxybenzoquinone, M Munakata, LP Wu, T Kuroda-Sowa, M Yamamoto, M Maekawa, K Moriwaki, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 268(2), 317 - 321, Feb. 1998 , Refereed
    Summary:The synthesis and characterization of a mixed-valence copper complex [Cu-II(bpy)(2)Cl](2)[(CuCl2)-Cl-I](2)(C6O6H4), where bpy=2,2'-bipyridine, is described. The structure contains discrete copper(II) cation and copper(I) anion groups. In the cation each divalent copper is Linked to two bpy molecules and one chloride ion in a trigonal bipyramidal fashion, whereas in the anion each monovalent copper is linearly bound to two chlorine atoms. The mixed-valence Cu(I/II) system is associated by multiple hydrogen bonding through tetrahydroxybenzoquinone, leading to an infinite chain structure of the complex. The complex was also characterized by spectroscopic studies. (C) 1998 Elsevier Science S.A.
  • Synthesis and structure of a two-dimensional copper(II) coordination polymer with 3,4,9,10-perylenetetracarboxylic acid and ethylenediamine, Y Suenaga, T Kuroda-Sowa, M Munakata, M Maekawa, POLYHEDRON, POLYHEDRON, 17(13-14), 2207 - 2211, 1998 , Refereed
    Summary:The crystal and molecular structure of a dinuclear copper(II) complex with 3,4,9,10-perylenetetracarboxylic acid (H(4)ptca) and ethylenediamine (en) [Cu-2(en)(4)(mu-ptca)] (EtOH)(2)(H2O)(6) has been determined by X-ray structural analysis. Each copper atom is coordinated by four-nitrogen atoms of two en molecules, one oxygen atom of bridging ptca(4-) and one water molecule in an octahedral arrangement. The resulting dinuclear copper(II) complex forms two-dimensional network through intermolecular hydrogen bonds between carboxylate of ptca4- and the water. (C) 1998 Elsevier Science Ltd; All rights reserved.
  • Synthesis and crystal structure of dinuclear and tetranuclear palladium dppm complexes. [Pd-2(mu-dppm)(2)(vpy)Cl] and [Pd-4(mu-dppm)(4)(mu-X)(2)](ClO4)(2) (X = Cl, Br and I), M Maekawa, M Munakata, T Kuroda-Sowa, Y Suenaga, POLYHEDRON, POLYHEDRON, 17(20), 3657 - 3663, 1998 , Refereed
    Summary:Reaction of the intermediate [Pd-2(mu-dppm)(2)](2+) which was prepared from [Pd-2(mu-dppm)(2)X-2] (X = Cl, Br and I) and AgClO4 in ethanol with 2-vinylpyridine (vpy) afforded dinuclear Pd(I) dppm complex [Pd-2(mu-dppm)(2)(vpy)Cl] (1). When the intermediate [Pd-2(mu-dppm)(2)](2+) was allowed to stand for a few days, tetranuclear Pd dppm complex [Pd-4(mu-dppm)(4)(mu-X)(2)](ClO4)(2) (X = Cl (2); Br (3) and I (4)) was systematically formed. The structure for 1 and 2 were crystallographically determined. On complex 1 two Pd atoms are doubly bridged by two dppm ligands to form an eight-membered Pd2P4C2 framework in a twist-chair conformation. Each Pd atoms is also coordinated by the Cl atom and the N atom of vpy in unsymmetrical side-by-side mode. The Pd-Pd distance is 2.597(2) Angstrom and the torsion angle between two Pd2P4 plane is 43.2 degrees. On the other hand four Pd atoms on 2 are bridged by four dppm ligands to form a rectangular Pd-4 core, which is composed of the shorter Pd-Pd separations (2.590(1) Angstrom) and the close Pd ... Pd separations (3.818(2) Angstrom). The later Pd ... Pd separation is also bridged by the Cl atom. The Pd-P distance (2.351(1) Angstrom) bridging the close Pd ... Pd separation is rather longer than that (2.238(2) Angstrom) bridging the shorter Pd-Pd separation. (C) 1998 Elsevier Science Ltd. All rights reserved.
  • Two-dimensional silver(I) compound with square mesh structure, [Ag(dcpz)](ClO4) (dcpz = pyrazine-2,3-dicarbonitrile), Y Suenaga, T Kuroda-Sowa, M Munakata, M Maekawa, POLYHEDRON, POLYHEDRON, 18(1-2), 191 - 195, 1998 , Refereed
    Summary:Silver(I) complex of pyrazine-2,3-dicarbonitrile (dcpz)] [Ag(dcpz)](ClO4) have been prepared and the molecular structure determined by X-ray crystallography. The silver ion prefers an octahedral coordination geometry comprising four nitrogen atoms from four different dcpz molecules and two oxygen atoms from ClO4- anion molecule. Each dcpz in turn bridges four Ag(I) centres leading to a square mesh arrangement of alternating metal cations and organic ligands. The square mesh sheet accumulates along the c-axis direction, consisting of a channel structure. (C) 1998 Elsevier Science Ltd. All rights reserved.
  • Structural control of copper(I) coordination polymers: Construction of one-, two-, and three-dimensional frameworks of tetrahedral copper(I) ions bridged by dicyanobenzene derivatives, T Kuroda-Sowa, T Horino, M Yamamoto, Y Ohno, H Maekawa, M Munakata, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 36(27), 6382 - 6389, Dec. 1997 , Refereed
    Summary:With the use of three dicyanobenzene derivatives as bridging ligands, four copper(I) coordination polymers, [Cu(dchq)(2)](ClO4)(Me2CO)(2) (1; dchq = 1,2-dicyanohydroquinone), [Cu(ipn)(2)[(PF6)(Me2CO) (2; ipn = 1,3-dicyanobenzene), and [Cu(dmtpn)(2)](X)(dmtpn)(THF) (3a (X = BF4), 3b (X = ClO4); dmtpn = 2,5-dimethylterephthalonitrile) were synthesized and characterized. Single-crystal X-ray analyses revealed that all copper(I) ions in these complexes have tetrahedral geometry and are coordinated by four ligands which also coordinate to the next copper ions, resulting in the formation of coordination polymer compounds. The polymer framework of 1 consists of one-dimensional chains that run along the a-axis direction and weakly interact with each other through pi-pi interactions between the dchq molecules and through hydrogen bonding. 2 has a two-dimensional sheet with a square arrangement of copper(I) ions. Stacking of the square lattice in the c-axis direction forms cavities in which the acetone molecules and PF6- anions are incorporated. Both 3a and 3b are isostructural and have triply interpenetrated three-dimensional diamond-like frameworks with pi-pi stacking columns of alternately coordinated and uncoordinated dmtpn molecules. It is demonstrated that the dimensionality of the polymer structures can be successfully controlled by the relative positions of two CN groups in the bridging Ligands. Crystallographic data are as follows. 1: C22H20CuCIN4O10, monoclinic, C2/c, a = 19.514(2) Angstrom, b = 10.526(2) Angstrom, c = 12.276(1) Angstrom, beta = 96.839(8)degrees, Z = 4. 2: C19H14CUF6N4OP, orthorhombic, P2(1)2(1)2(1), a = 12.743(2) Angstrom, b = 15.026(3) Angstrom, c = 11.362(2) Angstrom, Z = 4. 3a: C34H32BCuF4N6), monoclinic, Cc, a = 9.599(3) Angstrom, b = 27.298(5) Angstrom, c = 13.367(3) Angstrom, beta = 105.45(2)degrees, Z = 4. 3a: C34H32ClCuN6O5, monoclinic, Cc, a = 9.590(7) Angstrom,b = 27.429(3) Angstrom, c = 13.416(4) Angstrom, beta = 105.80(3)degrees, Z = 4.
  • Comparative X-ray studies of a copper(I) coordination polymer with 1,2,4,5-tetramethylmercaptobenzene (tmmb), [(CuX)(2)(tmmb)](n)(X=Br, I), Y Suenaga, M Maekawa, T Kuroda-Sowa, M Munakata, H Morimoto, N Hiyama, S Kitagawa, ANALYTICAL SCIENCES, ANALYTICAL SCIENCES, 13(6), 1047 - 1049, Dec. 1997 , Refereed
  • Two types of new polymeric copper(I) complexes of pyrazinecarboxamide having channel and helical structures, M Munakata, LP Wu, T KurodaSowa, M Maekawa, K Moriwaki, S Kitagawa, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 36(23), 5416 - 5418, Nov. 1997 , Refereed
  • Solid and solution structures of ternary gold(I) complexes with triphenylphosphine and nitrogen-containing ligands, M Munakata, SG Yan, M Maekawa, M Akiyama, S Kitagawa, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 4257(22), 4257 - 4262, Nov. 1997 , Refereed
    Summary:A series of gold(I) complexes [Au(PPh3)L]ClO4 (L = pyridine 1a, 2,6-dimethylpyridine 1b, 2,6-di-tert-butylpyridine 1c, quinoline 1d, acridine 1e, benzo[h]quinoline 1f, naphthyridine 2a, 1,10-phenanthroline 2b, 2,2'-biquinoline 2c, di-2-pyridyl ketone 2d, di-2-pyridylamine 3a or 2-(2-pyridyl)bemimidazole 3b) were prepared by reaction of L with [Au(PPh3)(ClO4)] which was synthesized in situ. All complexes were characterized by IR, UV/VIS and H-1 NMR spectroscopy. The crystal and molecular structures of Ib, 2a and 3b were investigated by single-crystal X-ray diffraction techniques. The gold(I) is co-ordinated to one nitrogen atom and one phosphine atom. Detailed H-1 NMR studies suggested that linear two-co-ordinated structures persist in solution and further that all the complexes [Au(PPh3)L]ClO4, (2a-2d), are fluxional species in which the co-ordination site of gold(I) rapidly exchanges between two nitrogen atoms of the ligand.
  • Construction and conductivity of W-type sandwich silver(I) polymers with pyrene and perylene, M Munakata, LP Wu, T KurodaSowa, M Maekawa, Y Suenaga, K Sugimoto, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 36(21), 4903 - 4905, Oct. 1997 , Refereed
  • Syntheses, structures and properties of linear copper(I) coordination polymers with tetrakis(ethylthio)tetrathiafulvalene and tetrakis(propylthio)tetrathiafulvalene, M Yamamoto, XM Gan, T KurodaSowa, M Maekawa, Y Suenaga, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 261(2), 169 - 174, Sep. 1997 , Refereed
    Summary:Two-linear coordination polymers composed of copper(I) cations and tetrakis(ethylthio)tetrathiafulvalene (TTC2-TTF) and tetrakis(propylthio)tetrathiafulvalene (TTC3-TTF) molecules have been synthesized by the reaction of copper(I) tetrafluoroborate with TTC2-TTF and copper(I) perchlorate with TTC3-TTF, respectively, in acetone under argon. The compounds, [Cu(TTC2-TTF)]BF4 (i) and [Cu(TTC3-TTF)]ClO4 (2), were characterized by spectroscopic and X-ray crystallographic methods. They are 1:I metal-ligand complexes in which each of the copper(I) ions is tetrahedrally coordinated by four sulfur atoms from the bridging TTC2-TTF or TTC3-TTF molecules to form coordination polymeric chains. 1 and 2 were doped with iodine to afford {[Cu(TTC2-TTF)]BF4}(I-3)(0.33) and {[Cu(TTC3-TTF)]ClO4}(I-3)(0.33), which exhibit conductivities of 2x10(-5) and 4x10(-5) S cm(-1), respectively, at 25 degrees C for compacted pellets.
  • Redetermination of crystal structure of bispotassium (mu-chloro)(bischloro)copper(I) K2CuCl3 with infinite chains, Y Suenaga, M Maekawa, T KurodaSowa, M Munakata, ANALYTICAL SCIENCES, ANALYTICAL SCIENCES, 13(4), 647 - 649, Aug. 1997 , Refereed
  • Crystal structure of dinuclear copper(I) complex with 1,2,4,5-tetramethylmercaptobenzene, [Cu(tmmb)I](2), Y Suenaga, M Maekawa, T KurodaSowa, M Munakata, H Morimoto, N Hiyama, S Kitagawa, ANALYTICAL SCIENCES, ANALYTICAL SCIENCES, 13(4), 651 - 652, Aug. 1997 , Refereed
  • Double hydrogen bond- and pi-pi-stacking-assembled two-dimensional copper(I) complex of 2-hydroxyquinoxaline, J Dai, M Yamamoto, T KurodaSowa, M Maekawa, Y Suenaga, M Munakata, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 36(12), 2688 - 2690, Jun. 1997 , Refereed
  • Preparation, characterization and X-ray crystal structures of I-2 and copper(II) complexes of 2,11-dithia[3.3]paracyclophane, M Yamamoto, LP Wu, T KurodaSowa, M Maekawa, Y Suenaga, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 258(1), 87 - 91, May 1997 , Refereed
    Summary:The crystal structures of dtpcpI(4) (1), [CuCl2(dtpcp)(EtOH)] (2) and [CuBr2(dtpcp)(MeOH)] (3), where dtpcp = 2,11-dithia[3,3]-paracyclophane, have been determined by X-ray crystallography. Complex 1 contains two crystallographically independent I(2)dtpcpI(2) molecules in the unit cell, each having crystallographical -1(C-i) symmetry. The structures of both 2 and 3 consist of a one-dimensional array of copper(II) ions linked via dithia-bridged paracyclophane. While 1 is an electric insulator at room temperature, the iodine oxidation of 2 and 3 produced charge-transfer complexes which gave conductivities 10(-5.5) and 10(-6.9) S cm(-1), respectively. Both 2 and 3 show the typical ESR signals and normal magnetic moments for a dilute copper(II) ion at room temperature, but exhibit an antiferromagnetic coupling at low temperature through the conjugated rr system of the bridging ligand.
  • Crystal structure of bis{cis-bis(diphenylphosphino)ethylene}palladium(0) acetone solvate, M Maekawa, T KurodaSowa, Y Suenaga, M Munakata, ANALYTICAL SCIENCES, ANALYTICAL SCIENCES, 13(2), 319 - 320, Apr. 1997 , Refereed
  • Synthesis, crystal structures and magnetic behavior of polymeric lanthanide complexes with benzenehexacarboxylic acid (mellitic acid), LP Wu, M Munakata, T KurodaSowa, M Maekawa, Y Suenaga, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 249(2), 183 - 189, Aug. 1996 , Refereed
    Summary:Three lanthanide complexes with mellitic acid, [Ce-2{C-6(COO)(6)}(H2O)(8)]. H2O (1), [Eu-2{C-6(COO)(6)}(H2O)(8)]. H2O (2) and [Yb-2{C-6(COO)(6)}(H2O)(10)]. 2H(2)O (3), have been synthesized and structurally characterized by X-ray crystallography and magnetic properties. The three compounds crystallize in the monoclinic space group P2(1)/n, with unit cell, dimensions of: a = 8.627(2), b = 13.218(2), c = 9.650(1) Angstrom, beta = 95.93(1)degrees and Z = 2 for 1; a = 8.505(2), b = 13.145(1), c = 9.536(2) Angstrom, beta = 94.73(2)degrees and Z = 2 for 2; a = 8.420(1), b = 9.224(4), c = 16.229(1) Angstrom, beta = 100.267(9)degrees and Z = 2 for 3. All three structures consist of an extended network of metal ions, coordinated to mellitate anions and water molecules linked by a complex hydrogen bonding. 1 and 2 are isomorphous with near isostructural [M(2){C-6(COO)6}(H2O)(8)] units in which the metal ion is coordinated by four water molecules and five oxygen atoms of the mellitate anions, and each mellitate group involves a tetrakis(bidentate) and bis(unidentate) coordination mode bridging six metal ions forming a threedimensional framework. In 3 the ytterbium atom is bound with five water molecules and three oxygen atoms of the mellitate anion, and each mellitate moiety bridges four dodecahedral Yb(III) ions yielding a two-dimensional sheet structure. The magnetic susceptibility of 1 and 3 as a function of temperature (5.0-300 K) exhibits a sharp maximum at 6.0 K for both compounds.
  • Syntheses, structures and properties of palladium(II) complexes with photochromic 4-methoxyazobenzene, LP Wu, Y Suenaga, T KurodaSowa, M Maekawa, K Furuichi, M Munakata, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 248(2), 147 - 152, Jul. 1996 , Refereed
    Summary:Two palladium(II) complexes with the photochromic ligand 4-methoxyazobenzene (MeOazbH), [Pd(MeOazb) (PhCN) (H2O)] (ClO4) (1) and [Pd(MeOazbH)(2)Cl-2] (2) were prepared and their molecular structures determined by X-ray crystallography. 1: triclinic, <P(1)over bar>, a=9.684(3), b=11.833(2), c=9.731(3) Angstrom, alpha=102.41(1), beta=94.54(3), gamma=94.82(2)degrees, V=1079.7(4) Angstrom(3), Z=2. 2: triclinic, P (1) over bar, a=9.497(3), b=9.719(4), c=8.226(3) Angstrom, alpha=96.43(4), beta=109.24(3), gamma=62.13(2)degrees, V=632.9(4) Angstrom(3), Z=1. The molecular structure of complex 1 shows a significantly distorted square planar coordination around the Pd atom and the MeOazb group forms a five-membered chelate ring with the metal ion by means of a sigma-bond at an ortho-carbon atom and the lone pair of the further nitrogen. In complex 2 the palladium atom lies on an inversion center, surrounded in an essentially square planar fashion by the symmetry related two MeOazbH ligands and two chloride ions. In contrast with the ortho-metalation reaction in 1, MeOazbH in 2 acts as a monodentate ligand to bind the metal center via a Pd-N sigma-bond. Electronic spectroscopic studies of the two complexes together with the free ligand were carried out in solution at room temperature and upon irradiation of light; while rigidity imparted to the MeOazb linkage by palladation in 1 inhibits its photochromic reaction, the monodentate-coordinated MeOazbH in 2 shows a trans-cis photoisomerization.
  • Self-assembly of copper(I) complexes into three-dimensional co-ordination polymers with channel networks by hydrogen bonding or by tridentate ligands, LP Wu, M Yamamoto, T KurodaSowa, M Maekawa, Y Suenaga, M Munakata, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 2031(10), 2031 - 2037, May 1996 , Refereed
    Summary:Reaction of the appropriate copper(I) salt with 3-cyano-6-methylpyridin-2(1H)-one (Hcmp) gave three polymeric co-ordination compounds, [Cu(cmp)(Hcmp)(3)]. C5H12 1, [Cu-2(Hcmp)(4)(Me(2)CO)(2)][BF4](2) 2 and [Cu-5(cmp)(4)]ClO4 3, the structures of which have been determined by X-ray crystallography. Complex 1 contains a three-dimensional supramolecular framework of tetrahedral CuN4 centres linked by intermolecular hydrogen bonds through the pyridone N and O atoms. The open square microchannels created enclathrate n-pentane as the guest molecule. Complex 2 contains a dimeric unit weakly bound by the bridging acetone oxygen atoms. Each Hcmp moiety in the dimer is hydrogen-bonded pairwise to one adjacent Hcmp molecule belonging to the other dimer giving a one-dimensional array of copper atoms. The unique structural feature of complex 3 is that it does not involve hydrogen bonding as in 1 or 2, instead each cmp monoanion employs all its three functional groups bridging three copper atoms forming a supramolecular channel architecture containing a Cu-4 cluster. The results are discussed in terms of designing new inorganic solids by the self-assembly of copper(I) complexes.
  • An unusual tetranuclear copper(II) acetate structure with an open cubane Cu4O4 framework, LP Wu, T KurodaSowa, M Maekawa, Y Suenaga, M Munakata, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 2179(10), 2179 - 2180, May 1996 , Refereed
    Summary:The tetranuclear copper(II) complex [{Cu(O(2)CMe)(OMe)}(4)] has been found to contain an unusual open cubane Cu4O4 framework defined by two interpenetrating copper and oxygen planes rather than two tetrahedra; it also shows strong antiferromagnetic coupling.
  • Reversible photochromism of a crystalline dithienylethene copper(I) polymer, M Munakata, LP Wu, T KurodaSowa, M Maekawa, Y Suenaga, K Furuichi, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 118(13), 3305 - 3306, Apr. 1996 , Refereed
  • One-, two- and three-dimensional copper(I) and silver(I) complexes of 2,11-dithia[3.3]paracyclophane, M Munakata, LP Wu, T KurodaSowa, M Maekawa, Y Suenaga, S Nakagawa, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 1525(8), 1525 - 1530, Apr. 1996 , Refereed
    Summary:Two copper(I) and one silver(I) complex of 2,11-dithia[3.3]paracyclophane (dtpcp), [Cu2Br2(dtpcp)(MeCN)(2)] 1, [Cu2I2(dtpcp)(2)] . thf 2 and [Ag(dtpcp)(NO3)] 3, have been synthesized and their molecular structures determined by X-ray crystallography. All three structures contain an infinite network comprising metal cations linked via ditha-bridged paracyclophane and the counter anions. Complexes 1 and 2 are not isostructural. The repeating dinuclear units [Cu2Br2(dtpcp)(MeCN)(2)] joined by dtpcp in 1 generate a one-dimensional polymeric chain running parallel to a diagonal axis of the triclinic cell. Complex 2 is a two-dimensional sheet structure in which a large ring containing six copper atoms includes a tetrahydrofuran molecule as guest inside the open cavity. The one-nitrate oxygen bridging two metal centres in complex 3 yields a unique three-dimensional channel framework of silver(I) ions. The iodine-doped black products of compounds 1-3 at room temperature exhibited conductivities of 10(-5.9), 10(-5.1) and 10(-4.7) S cm(-1), respectively.
  • Construction of three-dimensional supramolecular coordination copper(I) compounds with channel structures hosting a variety of anions by changing the hydrogen-bonding mode and distances, M Munakata, LP Wu, M Yamamoto, T KurodaSowa, M Maekawa, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 118(13), 3117 - 3124, Apr. 1996 , Refereed
    Summary:This paper describes four novel hydrogen-bonded copper(I) supramolecules with channel structures. The reactions of copper(I) salt with 3-cyano-6-methyl-2(1H)-pyridinone (Hcmp) in acetone have isolated four polymeric coordination products [Cu(Hcmp)(4)]X, where X = ClO4- (1), BF4- (2), PF6- (3), and CF3SO3- (4). All four compounds crystallized in the tetragonal system. Each structure contains a three-dimensional framework of tetrahedral CuN4 centers linked by intermolecular hydrogen bonds through pyridone N and O atoms in a head-to-tail mode. The very special structural features of the four compounds are related to the two types of hydrogen-bonding. Complexes 1 and 2 with smaller counteranions involve each Hcmp group hydrogen-bonded to two adjacent others (type A), which generates an open square channel filled with aligned ClO4- or BF4- ions, whereas 3 and 4 involve 1:1 pairwise hydrogen-bonding of Hcmp (type B) which results in four independent interpenetrating diamond-like frameworks with big cavities to accommodate larger anions of PF6- and CF3SO3-. Novel insight into the unique role played by the hydrogen-bonding mode and distances on the architecture of the network is discussed. The study indicates that the metal complex supramolecular structures can be rationally designed via hydrogen-bonding interactions.
  • TTC1TTF+ Cation coordinated to copper(I): Crystal structure and properties of [(TTC1)CuBr2](2), T KurodaSowa, A Hirota, M Munakata, M Maekawa, MOLECULAR CRYSTALS AND LIQUID CRYSTALS SCIENCE AND TECHNOLOGY SECTION A-MOLECULAR CRYSTALS AND LIQUID CRYSTALS, MOLECULAR CRYSTALS AND LIQUID CRYSTALS SCIENCE AND TECHNOLOGY SECTION A-MOLECULAR CRYSTALS AND LIQUID CRYSTALS, 285, 69 - 74, 1996 , Refereed
    Summary:One-electron oxidation of tetrakis(methylthio)tetrathiafulvalene (TTC1TTF) by CuBr2 yields a black copper(I) coordination compound, [(TTC1TTF)CuBr2](2) (1), whose structure has been determined by means of X-ray crystallography. 1 has a dimer structure consisting of a Cu2Br2 rhomboid with terminal Br- and TTC1TTF+ which coordinate to Cu(I) through one of four SMe groups. TTC1TTF+ form columnar stacks with the shortest S ... S contact of 3.44 Angstrom. Since most of TTC1TTF+ cation radicals in crystal form spin-pairs, a weak ESR signal observed at g = 2.008 is attributed to TTC1TTF+ radicals remain as free from pair formation located at crystal surface. Crystal Data: triclinic (P (1) over bar), a = 10.053(1) Angstrom, b = 10.618(1) Angstrom, c = 9.722(2) Angstrom, alpha = 90.85(1)degrees, beta = 91.04(1)degrees, gamma = 110.487(9)degrees, V = 971.7(3) Angstrom(3), Z = 1, R = 0.036, R(W) = 0.036.
  • Syntheses, characterization and X-ray crystal structures of tetrakis(ethylthio)tetrathiafulvalenium hexachlorodicopper(II) and hexabromodicopper(II), LP Wu, XM Gan, M Munakata, T KurodaSowa, M Maekawa, Y Suenaga, MOLECULAR CRYSTALS AND LIQUID CRYSTALS SCIENCE AND TECHNOLOGY SECTION A-MOLECULAR CRYSTALS AND LIQUID CRYSTALS, MOLECULAR CRYSTALS AND LIQUID CRYSTALS SCIENCE AND TECHNOLOGY SECTION A-MOLECULAR CRYSTALS AND LIQUID CRYSTALS, 285, 75 - 82, 1996 , Refereed
    Summary:Oxidation of tetrakis(ethylthio)tetrathiafulvalene (TTC2-TTF) with CuCl2 and CuBr2 in acetonitrile yielded the organic radical cation salts, (TTC2-TTF)2[Cu2Cl6] 1 and (TTC2-TTF)(2)[Cu2Br6] 2, whose structures have been determined by X-ray structure analysis. Both 1 and 2 crystallize in the triclinic system, space group P (1) over bar with one molecule per unit cell. 1: a = 12.065(4), b = 12.644(3), c = 8.988(2) Angstrom, alpha = 103.54(2), beta = 90.24(2), gamma = 112.42(2)degrees. 2: a = 12.330(3), b = 12.647(2), c = 8.956(2) Angstrom, alpha = 101.72(2), beta = 94.66(2), gamma = 111.69(1)degrees. Both structures consist of two segregated stacks of TTC2-TTF+ donors and Cu(2)X(6)(2-) accepters associated via short S ... X contacts. Consistent with the structural results, the two compounds exhibit low electrical conductivities with sigma 25 degrees C being 4 x 10(-8) and 8 x 10(-8) S cm(-1) for 1 and 2, respectively.
  • Preparation, electrochemistry and thermal analysis of two palladium(II) complexes with 1-aminopyrene and derivatives, J Dai, XD Yang, JP Sun, ZR Lu, M Munakata, M Maekawa, JOURNAL OF COORDINATION CHEMISTRY, JOURNAL OF COORDINATION CHEMISTRY, 38(4), 281 - 285, 1996 , Refereed
    Summary:Two palladium(II) complexes with aminopyrene and a derivative have been synthesized and characterized. In complex 1, Pd(apyr)(2)Cl-2 (apyr = 1-aminopyrene), the pyrenyl-pi-electrons do not conjugate with d-electrons of the metal, whereas complex 2, Pd(pmpa)Cl-2 (pmpa = N-(2-pyridylmethylene)-1-pyrenylamine) is a conjugated, planar molecule. Due to this, the oxidation potential and the electronic spectrum of the pyrenyl group of pmpa is significantly influenced by formation of the complex. Both iodine doped complexes show semiconductor properties (2.4 x 10(-4) S cm(-1) for 1 and 1.0 x 10(-4) S cm(-1) for 2). TG-DTG curves for 1 shows a single step decomposition. However, curves for complex 2 show a two-step decomposition, corresponding to the organic ligand pmpa. The iodine doped compounds are more stable than the original complexes. The quantity of doped iodine for 1 and 2 is 23 and 14%, respectively.
  • Co-ordinative versatility of 3,5-bis(2-pyridyl)pyrazole in silver and copper compounds, M Munakata, LP Wu, M Yamamoto, T KurodaSowa, M Maekawa, S Kawata, S Kitagawa, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 4099(24), 4099 - 4106, Dec. 1995 , Refereed
    Summary:Two silver(I) and one copper(ii) complex with 3,5-bis(2-pyridyl) pyrazole (Hbpypz) have been synthesized and their molecular structures determined by X-ray crystallography. In the dinuclear complex [Ag-2(Hbpypz)(4)][ClO4](2) . 2Me(2)CO there are two crystallographically independent monomeric units linked by intramolecular hydrogen bonds. In each unit Hbpypz only uses two of its four nitrogen atoms, acting as a typical bidentate chelate ligand. In the polymeric complex {[Ag(Hbpypz)] ClO4}(infinity) each silver(I) ion is co-ordinated to three nitrogen atoms of two different Hbpypz molecules and each ligand in turn bridges two separate Ag atoms forming an infinite-chain structure of macrocations with non-interacting ClO4- anions. The tetranuclear complex [Cu-4(bpypz)(4)(ClO4)(4)]. 2H(2)O consists of two weakly associated dimeric units coupled via stacking between the pyridine and pyrazole rings with an average spacing of 3.50 Angstrom, which gives rise to charge-transfer absorption bands in the near-UV region. The temperature dependence of the ESR spectrum and magnetic susceptibility indicates the presence of an antiferromagnetic interaction in the system. While Hbpypz is strictly planar in the copper(ii) complex, a non-coplanar conformation is observed in both silver(I) complexes, indicative of the unique co-ordinative versatility of the pyrazole derivative.
  • SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF CROWN THIOETHER COMPLEXES OF SILVER(I) AND COPPER(II), M MUNAKATA, LP WU, M YAMAMOTO, T KURODASOWA, M MAEKAWA, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 3215(19), 3215 - 3220, Oct. 1995 , Refereed
    Summary:The crown thioether silver(I) complexes {[AS{(OH)(2)[16]aneS(4)}]NO3}infinity 1 and {[Ag{(OH)(2) [16]aneS(4)}][O(2)CMe]}infinity 2 and the copper(II) complex [Cu{(OH)(2)[16]aneS(4)}][CIO4](2) 3, where (OH)(2)[16]aneS(4) = 1,5,9,13-tetrathiacyclohexadecane-3,11-diol, have been prepared by reaction of have been prepared by reaction of (OH)(2)[16]aneS(4) with the appropriate metal salt. The two silver structures are not isomorphous. Complex 1 crystallizes in the monoclinic space group C2 with a = 13.500(4). b = 9.178(2), c = 8.695(4) Angstrom, beta = 121.99(2)degrees and Z = 2. Silver(I) is tetrahedrally bound with four thioether groups from four symmetry-related macrocycles and each ligand molecule in turn co-ordinates to four separate silver(I) ions in an exodentate fashion to yield a three-dimensional tetrahedral polymeric network. Complex 2 crystallizes in the orthorhombic space group Pccn with a = 14.121(9), b = 17.203(8), c = 15.940(3) Angstrom and Z = 8. it contains two types of crystallographically different silver(I) ions. both of which are co-ordinated by four sulfur atoms from four symmetry-related macrocycles in a rather distorted-tetrahedral fashion. The silver atoms are in a two-dimensional sheet arrangement interconnected by the macrocycle. Complex 3 crystallizes in the monoclinic space group P2(1)/c with a = 7.820(2), b = 13.853(2), c = 9.627(2) Angstrom, beta = 90.85(2)degrees and Z = 2. The molecule is a discrete monomer in which the tetradentate macrocycle is in the endodentate conformation with four thioether donors in a precisely square-planar arrangement around the copper.
  • SYNTHESES, STRUCTURES AND PROPERTIES OF COPPER(1) COORDINATION POLYMERS WITH BRIDGING PHENAZINE - CONSTRUCTION OF ONE-DIMENSIONAL AND 2-DIMENSIONAL STRUCTURES WITH PI-PI STACKING OF PHENAZINE, T KURODASOWA, M MUNAKATA, H MATSUDA, S AKIYAMA, M MAEKAWA, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, (13), 2201 - 2208, Jul. 1995 , Refereed
    Summary:Four novel copper(I) phenazine (phz) compounds, [{Cu(phz)(NO3)}(infinity)] 1, [{Cu(acr)(2)(NO3)}(2)(phz)-(H2O)] 2 (acr = acridine). [{Cu-2(phz)(PFO3)}(infinity)] 3 and [{[Cu(phz)(MeCN)](2)(C16H10)(PF6)(2)}(infinity)] 4 (C16H10 = pyrene) have been synthesized and their molecular structures and packing have been determined by single-crystal X-ray diffraction methods. The copper atoms in 1 are bridged by phz forming an infinite one-dimensional zigzag chain. These bridging phz molecules have a pi-pi interaction between neighbouring chains forming an infinite columnar stack of phz molecules. The monomer complex, 2, has an infinite columnar stack of metal-free phz and metal-co-ordinated acr. Copper(I) atoms in 3 are bridged by phz and PFO32- alternately. The resulting one-dimensional chains are connected through a tetradentate, asymmetric PFO32- bridge, with pi-pi interaction between the phz molecules forming an infinite two-dimensional sheet structure. The backbone of compound 4 is almost the same as in 1 except that a pyrene molecule is intercalated into every other phz stack in a one-dimensional chain. The electrical conductivity of compound 3 and [{[Cu(phz)(MeCN)](2)(C16H10)(PF6)(2)I-1.3}(infinity)] 5, obtained by iodine doping of compound 4 were 1 x 10(-7.6) and 1 x 10(-4.7) S cm(-1), respectively. The electronic absorption bands of compounds 1, 3 and 4 which appeared around 700 nm are characteristic of copper(I) co-ordination polymers with bridging phz.
  • SYNTHESIS, STRUCTURE AND PROPERTIES OF A LINEAR COPPER(I) COORDINATION POLYMER WITH TETRAKIS(ETHYLTHIO)TETRATHIAFULVALENE, XM GAN, M MUNAKATA, T KURODASOWA, M MAEKAWA, M YAMAMOTO, POLYHEDRON, POLYHEDRON, 14(12), 1647 - 1651, Jun. 1995 , Refereed
    Summary:A new linear coordination polymer composed of copper(I) cations and tetrakis(ethylthio)tetrathiafulvalene (TTC2-TTF) molecules has been synthesized by the reaction of copper(I) perchlorate and TTC2-TTF in acetone under argon. The compound, [Cu(TTC2-TTF)]ClO4, was characterized by spectroscopic and X-ray crystallographic methods. It is a 1:1 metal-ligand complex in which each of the copper(I) ions is tetrahedrally coordinated by four sulphur atoms from the bridging TTC2-TTF molecules to form coordination polymeric chains which are separated from each other by the perchlorate anions in the crystal. The complex was doped with iodine to afford {[Cu(TTC2-TTF)] ClO4}I, which exhibits a conductivity of 6 x 10(-4) S cm(-1) at 25 degrees C for a compacted pellet.
  • SYNTHESES AND STRUCTURES OF ONE-DIMENSIONAL AND 2-DIMENSIONAL COPPER(I) COORDINATION POLYMERS WITH TETRAKIS(ETHYLTHIO)TETRATHIAFULVALENE (TTC2-TTF) AND THE PROPERTIES OF THEIR IODINE-DOPED COMPOUNDS, XM GAN, M MUNAKATA, T KURODASOWA, M MAEKAWA, Y MISAKI, POLYHEDRON, POLYHEDRON, 14(10), 1343 - 1350, May 1995 , Refereed
    Summary:Two copper(I) complexes with tetrakis(ethylthio)tetrathiafulvalene (TTC2-TTF), [(CuCl)(2)TTC2-TTF] (1) and [(CuBr)(2)TTC2-TTF] (2), have been synthesized and characterized by spectroscopic and X-ray crystallographic methods. Both 1 and 2 are neutral 2:1 (metal/ligand) complexes in which each metal ion is coordinated in a distorted tetrahedral geometry to two bridging halide ions and two sulphur atoms from TTC2-TTF. The crystal of 1 has a two-dimensional structure in which TTC2-TTF molecules are connected between novel helical CuCl frames, while the crystal of 2 has a one-dimensional polymeric chain structure. The average Cu-Cl and Cu-S bond lengths are 2.282(2) and 2,405(2) Angstrom in 1 and Cu-Br and Cu-S bond lengths are 2,445(2) and 2,349(1) Angstrom in 2, respectively. Compounds 1 and 2 were doped with iodine to afford [(CuCl)(2)TTC2-TTF]I (3) and [(CuBr)(2)TTC2-TTF]I (4) which exhibit electrical conductivities of 6 x 10(-7) and 3 x 10(-7) S cm(-1), respectively, at 25 degrees C for compacted pellets.
  • SYNTHESES AND STRUCTURES OF TETRANUCLEAR AND HEXANUCLEAR COPPER(I) COMPLEXES WITH IMINOMETHANETHIOLATO BRIDGES DERIVED FROM ISOTHIOCYANATE, T KURODASOWA, M MUNAKATA, M MIYAZAKI, M MAEKAWA, POLYHEDRON, POLYHEDRON, 14(8), 1003 - 1009, Apr. 1995 , Refereed
    Summary:Methylisothiocyanate, MeN=C=S, in ethanol reacted with copper(I) giving a tetranuclear complex [Cu{mu(3)-SC(=NMe)(OEt)}](4) (1). Similar reaction of allylisothiocyanate, CH2=CHCH2N=C=S, and copper(I) in methanol gave a hexanuclear complex, [Cu{mu(3)-SC(=NC3H5)(OMe)}](6) (2). They show tetrahedral Cu-4 and octahedral Cu-6 cores, respectively. There are two structural similarities in both complexes : (i) a thiolato moiety [-N=C(S-)-] which bridges three copper atoms with a monodentate nitrogen atom and a bridging sulphur atom and (ii) a trigonal planar geometry for copper(I) coordinated by one nitrogen atom and two sulphur atoms. Each iminomethanethiolato ligand is formed in situ in solvent. H-1 NMR shows the reaction is initiated by a coordination of an isothiocyanate to copper(I).
  • FORMATION OF A METALLOCYCLE BY DIMERIZATION OF ACRYLONITRILE - CRYSTAL-STRUCTURE OF THE HEXAKIS((1,4-DICYANOBUTANE-1,4-DIYL)NICKEL(II)) COMPLEX, M MAEKAWA, M MUNAKATA, T KURODASOWA, K HACHIYA, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 230(1-2), 249 - 252, Mar. 1995 , Refereed
    Summary:A novel hexanickel(II) complex [Ni-6(NCCHCH2CH2CHCN)(6)] (2) with 1,4-dicyanobutane-1,4-diyl (L) which was produced by the metal-induced dimerization of acrylonitrile (AN) has been isolated and the structure has been determined crystallographically. Complex 2 is triclinic, space group P (1) over bar, a=9.998(2), b=10.363(2), c=9.960(3) Angstrom, alpha=110.35(2), beta=103.46(2), gamma=88.97(2)degrees U=938.7(4) Angstrom(3), Z=1, R=0.029 and R(w)=0.034. Each nickel atom is coordinated by two carbon atoms of L and two nitrogen atoms of the cyano group of two other L, providing a square-planar geometry. The six nickel atoms are bridged by the cyano group and carbon atom to form the slightly distorted octahedral Ni-6 core.
  • A MOLECULAR CAVITY FOR TETRAHEDRAL AND Y-SHAPED ANIONS - SYNTHETIC AND STRUCTURAL STUDIES OF MACROCYCLIC DICOPPER(I) AND DISILVER(I) COMPOUNDS OF 1,6-BIS(DIPHENYLPHOSPHINO)HEXANE, S KITAGAWA, M KONDO, S KAWATA, S WADA, M MAEKAWA, M MUNAKATA, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 34(6), 1455 - 1465, Mar. 1995 , Refereed
    Summary:New binuclear macrocyclic systems of 1,6-bis(diphenylphosphino)hexane (dpph) and 1,4-bis(diphenylphosphino)-butane (dppb), [Cu-2(dppb)(2)(ClO4)(2)] (2), [Cu-2(dPPh)(2)(mu-X)(2)] (X = ClO4 (3), NO3 (4), PF2O2 (5), CH3CO2 (7), C2H5CO2 (8)), and [Ag-2(dpph)(2)(mu-ClO4)(2)] (6), have been synthesized and structurally characterized. A mononuclear copper(I) complex, [Cu-2(dppp)(2)]ClO4 (1) (dppp = 1,3-bis(diphenylphosphino)propane), was also prepared. The crystals of 1-6 are all triclinic, space group P $($) over bar$$ 1, with Z = 1 (2) and 2 (1, 3-5). Dimensions of the unit cells: 1, a = 12.221(6) Angstrom, b = 18.425(7) Angstrom, c = 11.981(7) Angstrom, alpha = 96.19(4)degrees, beta = 102.42(4)degrees, gamma = 70.57(4)degrees; 2, a = 11.978(8) Angstrom, b = 12.755(8) Angstrom, c = 19.372(4) Angstrom, alpha = 97.83(5)degrees, beta = 111.24(4)degrees, gamma = 64.85(5)degrees; 3, a = 12.154(7) Angstrom, b = 12.728(5) Angstrom, c = 10.007(7) Angstrom, alpha = 92.67(4)degrees; beta = 101.57(4)degrees, gamma = 101.56(6)degrees; 4, a = 15.421(3) Angstrom, b = 18.354(4) Angstrom, c = 10.066(4) Angstrom, alpha = 90.23(3)degrees, beta = 97.06(2)degrees, gamma = 89.27(2)degrees; 5, a = 12.060(2) Angstrom, b = 12.808(1) Angstrom, c = 10.120(1) Angstrom, alpha = 86.134(7)degrees, beta = 101.299(9)degrees, gamma = 102.367(8)degrees; 6, a = 12.035(7) Angstrom, b = 12.820(6) Angstrom, c = 10.240(5) Angstrom, alpha = 92.76(4)degrees, beta = 101.49(4)degrees, gamma = 101.39(4)degrees. For complexes of 3-5 each copper atom shares a tetrahedral geometry with the P2O2 donor set, giving a molecular structure having two rings: the common outer large ring of CuP(CH2)(6)PCuP(CH2)(6)P is composed of copper atoms and the bridging diphosphine ligands while the inner ring is CuOXOCuOXO (X = Cl, N, P) for 3-5, respectively. The distances of Cu-O fall within the shortest range for copper(I) complexes of each anion, indicating that copper-anion binding is strong even for anions having weak coordination ability. The size of cavity for the anion trap is estimated as the distance L between the two metal atoms in a molecule. The L values are 4.99-5.22 Angstrom for 3-5. Compound 1 shows a typical mononuclear structure with chelating dppp, while 2 gives a binuclear geometry, [Cu-2(mu-dppb)(2)(ClO4)(2)], with terminally coordinated ClO4 anions and a single macrocycle (L = 4.63 Angstrom) of CuP(CH2)(4)PCuP(CH2)(4)P. The ClO4- ion is prevented from bridging coordination, and this is accounted for by the ring size and spatial blocking of the phenyl groups of dppb. On this basis, the ligand having six methylene groups provides a cavity able to include anions such as tetrahedral ClO4- and Y-shaped NO3-. By P-31 NMR, the mononuclear and binuclear copper(I) compounds in solution were also examined, and their exchange processes are discussed. The silver compound (6) as a structural analog of 3 also affords the double ring, but the Ag-O distance is not so sufficiently short that the silver atom binds ClO4 as strongly as copper does. Other compounds with CH3CO2- (7), C2H5CO28, and VO3- (9) were also examined by IR and V-51 NMR spectroscopy. By using the copper(I) ion and diphosphine, we have succeeded in building large macrocyclic systems, where various small molecules or anions are included, proposing a new host-guest chemistry.
  • Syntheses, structures and properties of copper(I) co-ordination polymers with bridging phenazine: Construction of one- and two-dimensional structures with π-π stacking of phenazine, Takayoshi Kuroda-Sowa, Megumu Munakata, Hajime Matsuda, Shin-Ichi Akiyama, Masahiko Maekawa, Journal of the Chemical Society, Dalton Transactions, Journal of the Chemical Society, Dalton Transactions, 2201(13), 2201 - 2208, 1995 , Refereed
    Summary:Four novel copper(I) phenazine (phz) compounds, [{Cu(phz)(NO3)}∞] 1, [{Cu(acr)2(NO3)}2(phz)(H2O)] 2 (acr = acridine), [{Cu2(phz)(PFO3)}∞] 3 and [{[Cu(phz)(MeCN)]2(C16H10)(PF6) 2}∞] 4 (C16H10 = pyrene) have been synthesized and their molecular structures and packing have been determined by single-crystal X-ray diffraction methods. The copper atoms in 1 are bridged by phz forming an infinite one-dimensional zigzag chain. These bridging phz molecules have a π-π interaction between neighbouring chains forming an infinite columnar stack of phz molecules. The monomer complex, 2, has an infinite columnar stack of metal-free phz and metal-co-ordinated acr. Copper(I) atoms in 3 are bridged by phz and PFO32- alternately. The resulting one-dimensional chains are connected through a tetradentate, asymmetric PFO32- bridge, with π-π interaction between the phz molecules forming an infinite two-dimensional sheet structure. The backbone of compound 4 is almost the same as in 1 except that a pyrene molecule is intercalated into every other phz stack in a one-dimensional chain. The electrical conductivity of compound 3 and [{[Cu(phz)(MeCN)]2(C16H10)(PF6) 2I1.3}∞] 5, obtained by iodine doping of compound 4 were 1 × 10-7.6 and 1 × 10-4.7 S cm-1, respectively. The electronic absorption bands of compounds 1, 3 and 4 which appeared around 700 nm are characteristic of copper(I) co-ordination polymers with bridging phz.
  • Synthesis and structural characterization of crown thioether complexes of silver(I) and copper(II), Megumu Munakata, Liang Ping Wu, Mikiko Yamamoto, Takayoshi Kuroda-Sowa, Masahiko Maekawa, Journal of the Chemical Society, Dalton Transactions, Journal of the Chemical Society, Dalton Transactions, (19), 3215 - 3220, 1995 , Refereed
    Summary:The crown thioether silver(I) complexes {[Ag{(OH)2[16]aneS4}]NO3}∞ 1 and {[Ag{(OH)2[16]aneS4}][O2CMe]}∞ 2 and the copper(II) complex [Cu{(OH)2[16]aneS4}][ClO4]2 3, where (OH)2[16]aneS4 = 1,5,9,13-tetrathiacyclohexadecane-3,11-diol, have been prepared by reaction of (OH)2[16]aneS4 with the appropriate metal salt. The two silver structures are not isomorphous. Complex 1 crystallizes in the monoclinic space group C2 with a = 13.500(4), b = 9.178(2), c = 8.695(4) Å, β = 121.99(2)°and Z = 2. Silver(I) is tetrahedrally bound with four thioether group from four symmetry-related macrocycles and each ligand molecule in turn co-ordinates to four separate silver(I) ions in an exodentate fashion to yield a three-dimensional tetrahedral polymeric network. Complex 2 crystallizes in the orthorhombic space group Pccn with a = 14.121(9), b = 17.203(8), c = 15.940(3) Å and Z = 8. It contains two types of crystallographically different silver(I) ions, both of which are co-ordinated by four sulfur atoms from four symmetry-related macrocycles in a rather distorted-tetrahedral fashion. The silver atoms are in a two-dimensional sheet arrangement interconnected by the macrocycle. Complex 3 crystallizes in the monoclinic space group P21/c with a = 7.820(2), b = 13.853(2), c = 9.627(2) Å, β = 90.85(2)°and Z = 2. The molecule is a discrete monomer in which the tetradentate macrocycle is in the endodentate conformation with four thioether donors in a precisely square-planar arrangement around the copper.
  • Co-ordinative versatility of 3,5-bis(2-pyridyl)pyrazole in silver and copper compounds, Megumu Munakata, Liang Ping Wu, Mikiko Yamamoto, Takayoshi Kuroda-Sowa, Masahiko Maekawa, Satoshi Kawata, Susumu Kitagawa, Journal of the Chemical Society, Dalton Transactions, Journal of the Chemical Society, Dalton Transactions, (24), 4099 - 4106, 1995 , Refereed
    Summary:Two silver(I) and one copper(II) complex with 3,5-bis(2-pyridyl)pyrazole (Hbpypz) have been synthesized and their molecular structures determined by X-ray crystallography. In the dinuclear complex [Ag2(Hbpypz)4][CIO4] 2·2Me2CO there are two crystallographically independent monomeric units linked by intramolecular hydrogen bonds. In each unit Hbpypz only uses two of its four nitrogen atoms, acting as a typical bidentate chelate ligand. In the polymeric complex {[Ag(Hbpypz)]CIO4}∞ each silver(I) ion is co-ordinated to three nitrogen atoms of two different Hbpypz molecules and each ligand in turn bridges two spearate Ag atoms forming an infinite-chain structure of macrocations with non-interacting CIO4- anions. The tetranuclear complex [Cu4(bpypz)4(CIO4)4]·2H 2O consists of two weakly associated dimeric units coupled via intramolecular stacking between the pyridine and pyrazole rings with an average spacing of 3.50 Å, which gives rise to charge-transfer absorption bands in the near-UV region. The temperature dependence of the ESR spectrum and magnetic susceptibility indicates the presence of an antiferromagnetic interaction in the system. While Hbpypz is strictly planar in the copper(II) complex, a non-coplanar conformation is observed in both silver(I) complexes, indicative of the unique co-ordinative versatility of the pyrazole derivative.
  • SYNTHESIS, CRYSTAL-STRUCTURE AND CHARACTERIZATION OF NICKEL(0) ACRYLONITRILE COMPLEXES WITH A BIDENTATE N-DONOR LIGAND, M MAEKAWA, M MUNAKATA, T KURODASOWA, K HACHIYA, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 227(1), 137 - 143, Dec. 1994 , Refereed
    Summary:Three nickel(0) acrylonitrile complexes with a bidentate N-donor ligand, [Ni(biL)(AN)(2)] (bit = 4,4'-dimethyl-2,2'-bipyridine (Me(2)bpy); 1, 2,2'-dipyridylamine (dpa); 2, 2,2'-pyridylbenzimidazole (pbi); 3, AN=acrylonitrile), have been prepared and characterized. The crystal structures have been determined by X-ray single-crystal diffraction. Complex 1 is triclinic, space group P1, with a=10.279(2), b=11.071(1), c=7.5409(9) Angstrom, alpha=95.68(1), beta=99.26(1), gamma=85.03(1)degrees, U=840.6(2) Angstrom(3), Z=2, R=0.032 and R(W)=0.038. The nickel atom of 1 is coordinated by two N atoms of Me(2)bpy and the C=C moiety of two AN molecules, providing a distorted tetrahedral geometry. Complexes 2 and 3 have the following crystal data: 2, monoclinic space group P2(1)/n, a=8.755(4), b=13.713(2), c=12.740(2) Angstrom, beta=92.94(2)degrees, U=1527.5(8) Angstrom(3), Z=4, R=0.038 and R(W)=0.039; 3, monoclinic space group P2(1)/n, a=12.829(3), b= 8.068(1), c=17.024(2) Angstrom, beta=107.62(1)degrees, U=1679.5(5) Angstrom(3), Z=4, R=0.033 and R(W)=0.036. The geometries of 2 and 3 are similar to that of 1 except for the dihedral angles. The average Ni-N distance is 2.004, 2.034 and 2.045 Angstrom for 1, 2 and 3, respectively. The average C=C distance of AN is 1.402(2), 1.403(6) and 1.409(4) Angstrom for 1, 2 and 3, respectively. These C=C distances are rather longer than that of free AN (1.343 Angstrom), indicating contribution from a large pi back-donation. The IR and H-1 NMR results also support the presence of pi back-donation.
  • ALKYLATION OF 2-VINYLPYRIDINE AND CRYSTAL-STRUCTURE OF BIS((ACETYLACETONATE)(1-PYRIDYLBUTYL)NICKEL(II)) COMPLEX, M MAEKAWA, M MUNAKATA, T KURODASOWA, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 227(1), 149 - 151, Dec. 1994 , Refereed
    Summary:The alkylation of 2-vinylpyridine (2-vpy) was produced by the reaction of [Ni(acac)(2)] (acac=acetylacetone), 2-vpy and AlEt(3) to isolate the dinickel(II) complexes with 1-pyridylbutanate (L). Two nickel atoms are bridged by the N atom and carbonate atom of L to form the binuclear complex. Each Ni atom is also coordinated by two O atoms of acetylacetonate, providing the square-planar geometry. The bridging mode of L is head-to-tail coordination, and the eight-membered ring Ni2N2C4 framework has a rare staggered conformation.
  • COPPER(I) IODIDE COORDINATION POLYMER WITH TETRAKIS(ETHYLTHIO)TETRATHIAFULVALENE (TTC2-TTF) AND THE IODINE-DOPED COMPOUND, XM GAN, M MUNAKATA, T KURODASOWA, M MAEKAWA, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 67(11), 3009 - 3011, Nov. 1994 , Refereed
    Summary:The title complex was synthesized by the reaction of copper(I) iodide and tetrakis(ethylthio)-tetrathiafulvalene (TTC2-TTF) in acetonitrile under argon atmosphere. The new compound, [(CuI)(2)TTC2-TTF], crystallizes in the monoclinic system, space group P2(1)/m with unit-cell dimensions a=9.843(2), b=12.946 (2), c=10.079(1) Angstrom, beta=99.91(1)degrees, V=1265.2(4) Angstrom(3), and Z=2. It is a neutral 2:1 (metal/ligand) complex in which each metal ion is tetrahedrally coordinated by two bridging iodide ions and two sulfur atoms from TTC2-TTF to form coordination polymeric chains. The average Cu-I and Cu-S bond lengths are 2.601 and 2.369 Angstrom, respectively. The complex was doped with iodine to afford [(CuI)(2)TTC2-TTF]I-1.5 which exhibits a conductivity of 2x10(-3) Scm(-1) at 25 degrees C for a compacted pellet.
  • SYNTHESIS AND STRUCTURE OF A COPPER(I) COMPLEX WITH 1-AMINOPYRENE - BUILDING OF A 2D STRUCTURE COMPOSED OF STACKING PYRENE RINGS, M MUNAKATA, J DAI, M MAEKAWA, KS TAKAYOSHI, JT FUKUI, JOURNAL OF THE CHEMICAL SOCIETY-CHEMICAL COMMUNICATIONS, JOURNAL OF THE CHEMICAL SOCIETY-CHEMICAL COMMUNICATIONS, 2331(20), 2331 - 2332, Oct. 1994 , Refereed
    Summary:The first copper(i) complex with aminopyrene [Cu(apyr)3]ClO4.MeOH is synthesized and characterized crystallographically; the most remarkable feature of the compound is its 2D structure connected through intra- and inter-molecular stacking of the aromatic rings.
  • BUILDING A 2-DIMENSIONAL COORDINATION POLYMER HAVING A MULTILAYERED ARRANGEMENT - A MOLECULAR ASSEMBLY COMPRISING HANGING PHENAZINE MOLECULES BETWEEN POLYMERIC STAIR FRAMEWORKS OF COPPER(I) HALIDES, M MUNAKATA, T KURODASOWA, M MAEKAWA, A HONDA, S KITAGAWA, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 2771(19), 2771 - 2775, Oct. 1994 , Refereed
    Summary:Three copper(i) complexes with phenazine (phz), [{Cu2(mu-X)2(mu-phz))infinity] (X = 11, Br 2 or Cl 3) were synthesized and their molecular structures and packing determined by single-crystal X-ray diffraction methods. The copper atoms of the Cu2I2 rhomboid in 1 are bridged by phz molecules to give an infinite linear chain and the phz molecules overlap between the infinite chains with an interplanar spacing of 3.46 angstrom. Compounds 2 and 3 have two-dimensional sheets of hanging phz molecules between polymeric stair frameworks of CuBr and CuCl, respectively. The interplanar spacings of adjacent phz molecules for 2 and 3 are 3.40 and 3.36 angstrom, respectively. All three complexes exhibit an absorption band at about 710 nm characteristic of copper(i) co-ordination polymers with phz.
  • TETRAKIS[(MU-3-ETHOXY(N-METHYLIMINO)-METHANETHIOLATO)COPPER(I), T KURODASOWA, M MUNAKATA, M MIYAZAKI, M MAEKAWA, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, 50, 1026 - 1028, Jul. 1994 , Refereed
    Summary:Tetrakis[mu3-ethoxy(N-methylimino)methane-thiolato]-1kappaN,2:4kappa2S,2kappaN, 1:3kappa2S;3kappaN, 1:4kappa2S;4kappaN,-2:3kappa2S-tetracopper, [Cu2(C4H8NOS)2]2, contains a tetrahedral Cu, core surrounded by four effectively tridentate ethoxy(N-methylimino)methanethiolato (or O-ethyl N-methylcarbonimidothioato) ligands, CH3N=C(OC2H5)S-. Each Cu atom is coordinated by an N atom and two S atoms in a trigonal planar environment. There are two kinds of Cu(I)-Cu(I) distances (average 2.616 and 2.845 angstrom), resulting in a butterfly structure for the Cu4 core.
  • ARCHITECTURE OF 2D SHEETS WITH 6-MEMBERED RINGS OF COPPERS INTERCONNECTED BY 2,1,3-BENZOTHIADIAZOLES AND A LAYERED STRUCTURE COMPOSED OF THE 2D SHEETS, M MUNAKATA, T KURODASOWA, M MAEKAWA, M NAKAMURA, S AKIYAMA, S KITAGAWA, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 33(7), 1284 - 1291, Mar. 1994 , Refereed
    Summary:Three Cu(I) complexes and one Ag(I) complex with 2,1,3-benzothiadiazole (btd) and Cu(I) complexes with 5,6-benzopyrimidine (bpm), {[Cu2(btd)3(ClO4)](ClO6).2thF}infinity (1), [Cu(btd)(HPO3F)]infinity (2), [Cu(btd)(NO3)]infinity (3), {[Ag(btd)](ClO4)}infinity (4), and {[Cu2(bpm)2(C2H4)(Me2CO)](ClO4)2]infinity (5), were synthesized; their molecular structures and packing were determined by using single-crystal X-ray diffraction methods. Complex 1 is a 2D structure composed of six-membered rings of coppers interconnected by six btds, [Cu6(btd)6]6+. The coppers in the 2D sheet approximately lie in the same plane. The 2D sheet composed of the six-membered rings [Cu6(btd)4(HPO3F)4]2+ is still maintained in 2 although HPO3F- anions take part in the interconnecting as well as btd molecules. The Cu framework of the six-membered rings of coppers interconnected by btd and NO3-, [Cu6(btd)4(NO3)4]2+, in the 2D complex 3 is in a chair form and makes it possible to stack btd molecules within and between the 2D sheets, forming a layered structure similar to that of graphite. Ag atoms in 4 are coordinated to two nitrogen atoms of interconnecting btd molecules to give a linear chain, and the btd molecules partially overlap between the chains. Cu atoms in 5 are N-coordinated to the interconnecting bpm molecules to form a 1D compound. The roles of metal ion, ligand, and counteranion have been discussed in the construction of 2D sheets with the six-membered rings of metal ions interconnected by aromatic compounds and a layered structure composed of the 2D sheets. Crystal data: 1, monoclinic P2(1)/a, a = 17.817(2) angstrom, b = 11.220(2) angstrom, c = 18.186(3) angstrom, beta = 110.361(8)degrees, V = 3408(2) angstrom3, Z = 4, 4272 reflections, R = 0.051; 2, monoclinic P2(1)/a, a = 16.576(2) angstrom, b = 10.711(2) angstrom, c = 11.001(1) angstrom, beta = 101.29(1)degrees, V = 1915.4(8) angstrom3, Z = 4,2645 reflections, R = 0.045; 3, triclinic P1BAR, a = 9.757(2) angstrom, b = 11.593(3) angstrom, c = 8.124(2) angstrom, alpha = 110.23(2)degrees, beta = 101.20(2)degrees, gamma = 74.98(2)degrees, V = 827.1(3) angstrom3, Z = 2,1767 reflections, R = 0.030; 4, monoclinic C2/c, a = 13.483(5) angstrom, b = 20.384(3) angstrom, c = 7.278(7) angstrom, beta = 98.90(5)degrees, V = 1976(2) angstrom3, Z = 8, 2309 reflections, R = 0.045; 5, monoclinic C2/c, a = 11.099(2) angstrom, b = 19.106(2) angstrom, c = 12.558(2) angstrom, beta = 104.10(1)degrees, V = 2582.8(5) angstrom3, Z = 8, 2113 reflections, R = 0.052.
  • SYNTHESIS AND STRUCTURE OF DI-COPPER(1) AND TETRA-COPPER(I) COMPLEXES BRIDGED BY PYRIDAZINE, M MAEKAWA, M MUNAKATA, T KURODASOWA, Y NOZAKA, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 603(4), 603 - 607, Feb. 1994 , Refereed
    Summary:Novel di- and tetra-copper(I) complexes of pyridazine (pydz) have been prepared and determined crystallographically. The yellow crystals of the dicopper(I) complex, [Cu2(pydz)3(MeCN)2] [PF6]2, 1 are monoclinic, space group C2/c, with a = 21.720(6), b = 8.803(8), c = 15.778(6) angstrom, beta = 114.33(2)degrees, Z = 4, R = 0.056 and R' = 0.072. Two copper atoms are triply bridged by three pydz ligands to give a binuclear structure, in which the Cu ... Cu separation is 3.065(2) angstrom. Each Cu atom is co-ordinated by three N atoms of three pydz molecules and one N atom of a MeCN molecule, providing a distorted tetrahedral environment. The orange crystals of the tetracopper(I) complex, [Cu4(pydz)6][ClO4]4.2MeCO 2 are monoclinic, space group P2(1)/a, with a = 16.368(2), b = 13.860(2), c = 10.542(2) angstrom, beta = 102.25(1)degrees, Z = 2, R = 0.050 and R' = 0.058. Two Cu atoms are bridged by four N atoms of two pydz molecules to form a six-membered N2Cu2N2 framework. Furthermore, two parallel NCuN2 frameworks are linked by two different pydz molecules to give a tetranuclear structure. Four Cu atoms are coplanar and each Cu atom is in a trigonal-square environment. The shortest Cu ... Cu separations are 3.096(1) and 3.264(1) angstrom. If in the preparation of 2 ethylene or CO atmospheres are employed instead of Ar, copper(I) pydz adducts with C2H4 or CO are obtained which have been characterized by IR and H-1 NMR spectroscopy. The former shows nu(c=c) of C2H4 at 1541 cm-1; the latter shows nu(co) at 2108 cm-1.
  • Synthesis and structure of di- and tetra-copper(I) complexes bridged by pyridazine, Masahiko Maekawa, Megumu Munakata, Takayoshi Kuroda-Sowa, Youichi Nozaka, Journal of the Chemical Society, Dalton Transactions, Journal of the Chemical Society, Dalton Transactions, (4), 603 - 607, 1994 , Refereed
    Summary:Novel di- and tetra-copper(I) complexes of pyridazine (pydz) have been prepared and determined crystallographically. The yellow crystals of the dicopper(I) complex, [Cu2(pydz)3(MeCN)2][PF6]2 1 are monoclinic, space group C2/c, with a = 21.720(6), b = 8.803(8), c = 15.778(6) Å, β = 114.33(2)°, Z = 4, R = 0.056 and R′ = 0.072. Two copper atoms are triply bridged by three pydz ligands to give a binuclear structure, in which the Cu ⋯ Cu separation is 3.065(2) Å. Each Cu atom is co-ordinated by three N atoms of three pydz molecules and one N atom of a MeCN molecule, providing a distorted tetrahedral environment. The orange crystals of the tetracopper(I) complex, [Cu4(pydz)6] [ClO4]4·2Me2CO 2 are monoclinic, space group P21/a, with a = 16.368(2), b = 13.860(2), c = 10.542(2) Å, β = 102.25(1)°, Z = 2, R = 0.050 and R′ = 0.058. Two Cu atoms are bridged by four N atoms of two pydz molecules to form a six-membered N2Cu2N2 framework. Furthermore, two parallel N2Cu2N2 frameworks are linked by two different pydz molecules to give a tetranuclear structure. Four Cu atoms are coplanar and each Cu atom is in a trigonal-square environment. The shortest Cu ⋯ Cu separations are 3.096(1) and 3.264(1) Å. If in the preparation of 2 ethylene or CO atmospheres are employed instead of Ar, copper(I) pydz adducts with C2H4 or CO are obtained which have been characterized by IR and 1H NMR spectroscopy. The former shows vC=C of C2H4 at 1541 cm-1 the latter shows νco at 2108 cm-1.
  • Building a two-dimensional co-ordination polymer having a multilayered arrangement. A molecular assembly comprising hanging phenazine molecules between polymeric stair frameworks of copper(I) halides, Megumu Munakata, Takayoshi Kuroda-Sowa, Masahiko Maekawa, Akihiro Honda, Susumu Kitagawa, Journal of the Chemical Society, Dalton Transactions, Journal of the Chemical Society, Dalton Transactions, (19), 2771 - 2775, 1994 , Refereed
    Summary:Three copper(I) complexes with phenazine (phz), [{Cu2(μ-X)2(μ-phz)}∞] (X = I 1, Br 2 or Cl 3) were synthesized and their molecular structures and packing determined by single-crystal X-ray diffraction methods. The copper atoms of the Cu2I2 rhomboid in 1 are bridged by phz molecules to give an infinite linear chain and the phz molecules overlap between the infinite chains with an interplanar spacing of 3.46 Å. Compounds 2 and 3 have two-dimensional sheets of hanging phz molecules between polymeric stair frameworks of CuBr and CuCl, respectively. The interplanar spacings of adjacent phz molecules for 2 and 3 are 3.40 and 3.36 Å, respectively. All three complexes exhibit an absorption band at about 710 nm characteristic of copper(I) co-ordination polymers with phz.
  • CRYSTAL-STRUCTURE OF BIS(2-MERCAPTOTHIAZOLINE)COPPER(I) CHLORIDE, [CU(MTZ)2CL], M MAEKAWA, S KITAGAWA, Y NOZAKA, M MUNAKATA, T KURODASOWA, ANALYTICAL SCIENCES, ANALYTICAL SCIENCES, 9(6), 887 - 888, Dec. 1993 , Refereed
  • STRUCTURE OF A TRINUCLEAR NICKEL(II) COMPLEX BRIDGED BY 3,5-DIMETHYLPYRAZOLATE (3,5-ME2PZ), [NI3(3,5-ME2PZ)4(ACAC)2], M MAEKAWA, M MUNAKATA, T KURODA, Y NOZAKA, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 208(2), 243 - 244, Jun. 1993 , Refereed
    Summary:A novel trinuclear nickel(II) complex, [Ni3(3,5-Me2pz)4(acac)2] (3,5-Me2pz = 3,5-dimethylpyrazolate, acac = acetylacetone), has been prepared and characterized crystallographically. The terminal and center nickel atoms are bridged by two 3,5-Me2pz, providing a trinuclear structure. The geometry of each nickel atom is square planar (SqPl) and these planes provide the zigzag mode. This is the first crystal structure of a trinuclear nickel(II) complex having a (SqPl)-(SqPl)-(SqPl) coordination arrangement. The Ni(l) ... Ni(2) separation is 3.1972(5) angstrom and the Ni(II) complex has no attractive Ni(II)... Ni(II) interaction. The averaged Ni-N distance of 3,5-Me2Pz and Ni-O distance of acac are 1.876 and 1.850 angstrom, respectively.
  • SYNTHESIS, STRUCTURES, AND PROPERTIES OF THE MOLECULAR ASSEMBLIES OF COPPER(I) AND SILVER(I) COMPLEXES WITH PHENAZINE - NOVEL DONOR-ACCEPTOR AND HUGE POLYNUCLEAR COMPLEXES, M MUNAKATA, S KITAGAWA, N UJIMARU, M NAKAMURA, M MAEKAWA, H MATSUDA, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 32(6), 826 - 832, Mar. 1993 , Refereed
    Summary:Three copper(I) and two silver(I) complexes with phenazine (phz), [Cu2(phz)3(MeOH)2](phz)(PF6)2 (1), [Cu(phz)2(H2O)]ClO4(2), [Cu(phz)2(NO3)] (3), {[Ag(phz)]ClO4}infinity (4), and [Ag2(phz)(NO3)2]infinity (5), were synthesized, and their molecular structures and packings were determined by using single-crystal X-ray diffraction methods. 1 is composed of infinite stacks of alternating metal-free phz molecules and the dicopper complex cations [Cu2(PhZ)3(MeOH)2]2+ and gives a CT band from the latter to the former at 710 nm indicative of a donor-acceptor complex. One phz in 2 and an opposite phz in another molecule alternatively stacked to give infinite columns. The copper of 3 is coordinated to NO3- and phz in a tetrahedral geometry. The molecular packing of 4 is composed of infinite linear chains of -Ag-phz-Ag-phz- along the a axis and a pi-pi interaction of the phz molecules between the chains along the c axis. The 3D complex 5 is made of a 2D framework of six-membered rings of silvers, a weak Ag-O bonding, and a pi-pi interaction of phz molecules between the 2D sheets. Solvent and counteranion as well as metal ion have been shown to play an important role in the molecular packing of metal complexes with phz because they are coordinated to metal ion to change the complex structure. Crystal data: 1, triclinic P1BAR-, alpha = 13.008(2) angstrom, b = 13.694(2) angstrom, c = 7.789(1) angstrom, a = 102.50(1)-degrees, beta = 105.02(1)-degrees, gamma = 72.81 (1)-degrees, V - 1256.4(3) angstrom3, Z = 2, 3568 reflections, R = 0.069; 2, triclinic P1BAR, a = 10.811(4) angstrom, b = 12.576(3) angstrom, c = 8.992(1) angstrom, alpha = 105.20(1)-degrees, beta = 92.59(2)-degrees, gamma = 110.90(5)-degrees, V = 1089.0(5) angstrom3, Z = 2, 3579 reflections, R = 0.045; 3, monoclinic P2(1)/n, a = 10.686(2) angstrom, b = 26.937(1) angstrom, c = 7.219(2) angstrom, beta = 102.18(1)-degrees, V = 2031(1) angstrom3, Z = 4, 2256 reflections, R = 0.035; 4, triclinic P1BAR, a = 7.2044(6) angstrom, b = 12.943(2) angstrom, c = 7.138(2) angstrom, a = 98.64(2)-degrees, beta = 98.70(1)-degrees, gamma = 89.92-degrees, V = 650.3(2) angstrom3, Z = 2, 2275 reflections, R = 0.034; 5, monoclinic P2(1)/n, a = 5.007(3) angstrom, b = 19.454(2) angstrom, c = 7.248(6) angstrom, beta = 102.18(1)-degrees, V = 685.0(7) angstrom3, Z = 4, 2256 reflections, R = 0.035.
  • CRYSTAL-STRUCTURE OF TETRAKIS(2-METHYLPYRAZINE)COPPER(II) PERCHLORATE, [CU(2-MEPZ)4](CLO4)2, M MAEKAWA, S KITAGAWA, T TANIMURA, M MUNAKATA, T YONEZAWA, ANALYTICAL SCIENCES, ANALYTICAL SCIENCES, 8(6), 899 - 900, Dec. 1992 , Refereed
  • SYNTHESIS, FORMATION-CONSTANTS AND STRUCTURES OF TERNARY COPPER(I) COMPLEXES WITH 1,10-PHENANTHROLINE AND ALKYNES, M MUNAKATA, S KITAGAWA, KAWADA, I, M MAEKAWA, H SHIMONO, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 2225(14), 2225 - 2230, Jul. 1992 , Refereed
    Summary:Ternary copper(i) complexes with alkynes and 1,10-phenanthroline (phen) have been prepared and characterized by their formation constants, IR spectra, H-1 and C-13 NMR spectra, The structures of three complexes, [Cu(phen)(HC=CR)]ClO4 (R = H 1, Ph 2 or CO2Et 3) have been determined using single-crystal X-ray methods. Each copper atom in all three complexes is co-ordinated to two nitrogen atoms of phen and an alkyne molecule in a trigonal-planar arrangement. The alkyne is sideways bonded onto the copper atom. The C=C bond distances of 1.190(7) (1), 1.218(13) (2) and 1.193(10) angstrom (3) are slightly longer than those of the free alkynes and indicate that pi-back donation from copper to the alkyne is weak. The reduction of the C=C stretching frequency for metal-alkyne complexes is correlated to the acetylenic bend-back angles and the lengthening of the C=C distance of the alkyne upon co-ordination. The copper-carbon and -nitrogen distances for 1 and 2 are essentially the same as those for the corresponding olefin complexes.
  • Synthesis, formation constants and structures of ternary copper(I) complexes with 1,10-phenanthroline and alkynes, Megumu Munakata, Susumu Kitagawa, Ichiro Kawada, Masahiko Maekawa, Hisao Shimono, Journal of the Chemical Society, Dalton Transactions, Journal of the Chemical Society, Dalton Transactions, (14), 2225 - 2230, 1992 , Refereed
    Summary:Ternary copper(I) complexes with alkynes and 1,10-phenanthroline (phen) have been prepared and characterized by their formation constants, IR spectra, 1H and 13C NMR spectra. The structures of three complexes, [Cu(phen)(HC≡CR)]ClO4 (R = H 1, Ph 2 or CO2Et 3) have been determined using single-crystal X-ray methods. Each copper atom in all three complexes is co-ordinated to two nitrogen atoms of phen and an alkyne molecule in a trigonal-planar arrangement. The alkyne is sideways bonded onto the copper atom. The C≡C bond distances of 1.190(7) (1), 1.218(13) (2) and 1.193(10) Å (3) are slightly longer than those of the free alkynes and indicate that π back donation from copper to the alkyne is weak. The reduction of the C≡C stretching frequency for metal-alkyne complexes is correlated to the acetylenic bend-back angles and the lenghthening of the C≡C distance of the alkyne upon co-ordination. The copper-carbon and -nitrogen distances for 1 and 2 are essentially the same as those for the corresponding olefin complexes.
  • SYNTHESIS AND X-RAY CRYSTAL-STRUCTURE OF THE DICOPPER(I) COMPLEX OF 2-(DIPHENYLPHOSPHINO)PYRIDINE (PH2PPY) [CU2(MU-PH2PPY)2(CH3CN)2](PF6)2, M MAEKAWA, M MUNAKATA, S KITAGAWA, T YONEZAWA, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 64(7), 2286 - 2288, Jul. 1991 , Refereed
    Summary:The dicopper(I) complex with 2-(diphenylphosphino)pyridine (Ph2Ppy), [Cu2(mu-Ph2Ppy)2(CH3CN)2](PF6)2 has been prepared. The crystal structure has been determined crystallographically: Space group P1BAR, a = 10.807(6), b = 11.756(8), c = 8.606(7) angstrom, alpha = 90.36(6), beta = 95.98(5), gamma = 92.90(5)-degrees, Z = 1; R = 0.067. The two copper atoms are bridged by two Ph2Ppy molecules in a head-to-tail arrangement, resulting in a rare staggered conformation of the eight-membered ring Cu2P2-N2C2, whose factor is concerned with the coordination numbers of the central metal atoms. H-1 NMR studies show that the ligand of a CH3CN in the titled compound undergoes dissociation in acetone solution.
  • CRYSTAL-STRUCTURE OF (2,2'-BIPYRIDINE)DICHLOROPALLADIUM(II), M MAEKAWA, M MUNAKATA, S KITAGAWA, M NAKAMURA, ANALYTICAL SCIENCES, ANALYTICAL SCIENCES, 7(3), 521 - 522, Jun. 1991 , Refereed
  • SYNTHESIS, PROPERTIES AND CRYSTAL-STRUCTURES OF DICOPPER(I) AND DISILVER(I) COMPLEXES WITH 1,8-NAPHTHYRIDINE (NAPY) - [CU2(NAPY)2](CLO4)2 AND [AG2(NAPY)2](CLO4)2, M MUNAKATA, M MAEKAWA, S KITAGAWA, M ADACHI, H MASUDA, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 167(2), 181 - 188, Jan. 1990 , Refereed
  • SYNTHESIS AND STRUCTURES OF (2,9-DIMETHYL-1,10-PHENANTHROLINE)(ACETONITRILE)COPPER(I) PERCHLORATE AND HEXAFLUOROPHOSPHATE - A CORRELATION BETWEEN BOND ANGLES AND BOND DISTANCES IN T-SHAPED AND Y-SHAPED 3-COORDINATE COPPER(I) COMPLEXES, M MUNAKATA, M MAEKAWA, S KITAGAWA, S MATSUYAMA, H MASUDA, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 28(23), 4300 - 4302, Nov. 1989 , Refereed
  • NUCLEAR MAGNETIC-RESONANCE STUDIES OF DICOPPER(II) COMPLEXES WITH BINUCLEATING LIGANDS CONTAINING IMIDAZOLES, M MAEKAWA, S KITAGAWA, M MUNAKATA, H MASUDA, INORGANIC CHEMISTRY, INORGANIC CHEMISTRY, 28(10), 1904 - 1909, May 1989 , Refereed
  • SYNTHESIS AND H-1-NMR SPECTRA OF BINUCLEAR COPPER(II) COMPLEXES WITH COPPER(II)-COPPER(II) INTERACTION AS AN OXYHEMOCYANIN MODEL, M MAEKAWA, S KITAGAWA, M MUNAKATA, NIPPON KAGAKU KAISHI, NIPPON KAGAKU KAISHI, (4), 438 - 444, Apr. 1988 , Refereed
  • DEUTERON NMR-SPECTROSCOPY OF COPPER(II) COMPLEXES IN SOLUTION .1. (5,7,7,12,14,14,-HEXAMETHYL-1,4,8,11-TETRAAZACYCLOTETRADECA-4,11-DIENE)-COPPER(II) AND ITS DERIVATIVES IN NONAQUEOUS SOLVENT, S KITAGAWA, M MUNAKATA, M TSURUMI, M MAEKAWA, INORGANICA CHIMICA ACTA, INORGANICA CHIMICA ACTA, 121(2), 113 - 117, Nov. 1986 , Refereed
  • Books etc

    • Construction of the molecular assemblies of copper(I) and silver(I) complexes with phenazine and control of their properties, New Functionality Materials, Volume C Synthetic Process and Control of Fructinality Materials elsevier Science Publisers,   1993

    Conference Activities & Talks

    • Cu(I) metallomacrocycle and coordination polymers with 2,2';5',4''-terpyridine directed by anions and solvents, T. Hayashi, M. Maekawa, T. Okubo, T.Kuroda-Sowa, The 7th Asian Conference on Coordination Chemistry (ACCC7 2019),   2019 10
    • Structural controls and properties of novel polynuclear Cu(I)-C2H4 complexes directed by counter anions, T. Hayashi, M. Maekawa, T. Okubo, T. Kuroda-Sowa,   2019 03
    • Heterometallic Ag(I)-Ir(III) hydride coordination polymers bridged by Ir(III) metalloligands, M. Maekawa, Y. Kubo, T. Okubo, T. Kuroda-Sowa, The 43th International Conference on Coordination Chemistry (ICCC 2018),   2018 07
    • Syntheses, crystal structures and properties of novel heterometallic polynuclear {Cu(I), Ag(I)}-Ir(III) complexes conducted by Ir(III) hydride metalloligands, S. Oda, M. Maekawa, T. Okubo, T. Kuroda-Sowa, 日本化学会第98春季年会(2018),   2018 03
    • Syntheses, structures and properties of novel Cu(I) coordination polymers with multidentate nitrogen ligands, T. Hayashi, M. Maekawa, T. Okubo, T. Kuroda-Sowa, 日本化学会第98春季年会(2018),   2018 03
    • Syntheses, structures and properties of novel polynuclear Cu(I) ethylene complexes with the related terpyridine ligands, M. Yabuta, M. Maekawa, T. Okubo, T. Kuroda-Sowa, 日本化学会第98春季年会(2018),   2018 03
    • Heterometallic Ag(I)−Ir(III) hydride coordination polymers bridged by Ir(III) metalloligands, M. Maekawa, Y. Kubo, T. Okubo, T. Kuroda-Sowa, M. Munakata, The 6th Asian Conference on Coordination Chemistry (ACCC 2017),   2017 07
    • Syntheses, structures and properties of heterometallic coordinationpolymers bridged by Ir(III) hydride metalloligands, ODA, Shoki, MAEKAWA, Masahiko, OKUBO, Takashi, KURODA-SOWA, Takayoshi,   2017 03
    • Syntheses and structures of novel polynuclear Cu(I) complexes withthe related terpyridine ligands, YABUTA, Mafuyu, MAEKAWA, Masahiko, OKUBO, Takashi, KURODA-SOWA, Takayoshi,   2017 03
    • Diverse copper(I) ethylene complexes with related 3,6-bis(2-pyridyl)-1,2,4,5-tetrazine ligands, Masahiko Maekawa, Takashi Okubo, Takayoshi Kuroda-Sowa, Megumu Munakata, The 2015 International Chemical Congress of Pacific Basin Societies (Pacifichem2015),   2015 12
    • Structural Controls of Cu(I)-C2H4 Coordination Polymers with 4,4’-Bipyrimidine Directed by Anions and Solvents, Masahiko Maekawa, Kunihisa Sugimoto, Takashi Okubo, Takayoshi Kuroda-Sowa, Megumu Munakata, Susumu kitagawa, 4th International Conference on Metal-Organic Frameworks and Open Framework Compounds (MOF2014),   2014 09
    • Structurally Diverse Copper(I) Ethylene Adducts with Related 3,6-BIS(2-PYRIDYL)-1,2,4,5-Tetrazine Ligands, M. Maekawa, K. Sugimoto, T. Okubo, T. Kuroda-Sowa, M. Munakata, S. Kitagawa, The 41th International Conference on Coordination Chemistry (ICCC41),   2014 07
    • Structural controls of Cu(I) C2H4 coordination polymers of 4,4’-bipyrimidine, The 40th International Conference on Coordination Chemistry (ICCC40),   2012 09 , The 40th International Conference on Coordination Chemistry (ICCC40)
    • Novel mono- and dinuclear Iridium(III) hydride complexes of 2,2’-bipyrimidine, The 40th International Conference on Coordination Chemistry (ICCC40),   2012 09 , The 40th International Conference on Coordination Chemistry (ICCC40)
    • First Cu(I) coordination polymers of 4,4’-biquinazoline and the C2H4 adduct, The 40th International Conference on Coordination Chemistry (ICCC40),   2012 09 , The 40th International Conference on Coordination Chemistry (ICCC40)
    • Novel Cu(I) metallamacrocycles toward structurally and functionally new inorganic anion receptors, The 2010 International Chemical Congress of Pacific Basin Societies (Pacifichem 2010),   2010 12 , The 2010 International Chemical Congress of Pacific Basin Societies (Pacifichem 2010)
    • Synthesis and structures of novel Cu(I) ethylene complexes with a tetrazine anion radical ring,   2010 03
    • Synthesis of Cu(I) and Ag(I) Metallamacrocycles as Structurally and Functionally New Inorganic Anion Receptors, The second Asian Conference on Coordination Chemistry (2nd ACCC),   2009 11 , The second Asian Conference on Coordination Chemistry (2nd ACCC)
    • Novel Cu(I) Ethylene Complexes Three?Dimensionally Self?Assembled by an Intermolecular π?π Stacking Interaction and a C?H???N Contact, The second Asian Conference on Coordination Chemistry (2nd ACCC),   2009 11 , The second Asian Conference on Coordination Chemistry (2nd ACCC)
    • Self-assemblies of novel Cu(I) metallamacrocyclic carbonyl adducts by anion templation,   2009 03
    • Self-assemblies of novel Cu(I) metallamacrocyclic ethylene adducts by 4,4'-bipyrimidine derivatives,   2009 03
    • Self-assemblies of novel Cu(I) and Ag(I) coordination polymers by anion templation,   2008 03
    • The Redox Behavior of Binuclear Metal Complexes with Bis(catecholate) Ligand,   2007 03
    • Syntheses and Properties of Binuclear Metal Complexes with Conjugated Bis(catecholate) Ligand.,   2006 09
    • Self-assembly of Cu(I) and Ag(I) metallocycles by anion templation,   2006 09
    • Structures and Properties of Silver(I) Coordination Polymer with Benzylthioether Ligand,   2006 03
    • Unique Ag(I) metallomacrocycles encapsulating a XF62- anion (X=Si, Ge and Sn) in the sandwich structure,   2006 03
    • 2-Dimensional Silver(I) Coordination Polymer with Twisted Naphthalene Rings,   2005 12
    • Syntheses and structural characterization of novel mono- and dinuclear iridium hydrido complexes with polydentate nitrogen ligands, The 2005 International Chemical Congress of Pacific Basin Societies (Pacifichem2005),   2005 12 , The 2005 International Chemical Congress of Pacific Basin Societies (Pacifichem2005)
    • Two structural isomers of Mn12-benzoate induced by coexistence of one or two napy molecules, The 2005 International Chemical Congress of Pacific Basin Societies,   2005 12 , The 2005 International Chemical Congress of Pacific Basin Societies
    • Effect of diphenylphosphate (dpp) substitution on the structure and magnetic properties of Mn12 SMMs, The 2005 International Chemical Congress of Pacific Basin Societies,   2005 12 , The 2005 International Chemical Congress of Pacific Basin Societies
    • Abrupt spin transition and LIESST phenomena observed in a Fe(II) complex with a N4O2 donor set, The 2005 International Chemical Congress of Pacific Basin Societies,   2005 12 , The 2005 International Chemical Congress of Pacific Basin Societies
    • Syntheses and Properties of Co(III) Dinuclear Complexes with π Conjugated Biscatecholate Ligands,   2005 09
    • Syntheses and structures of rhodium and iridium complexes with polycyclic aromatic hydrocarbon ligands,   2005 03
    • A Novel Mn12 Single-Molecule Magnet [Mn12O12(OAc)12(dpp)4], IX th International Conference on Molecule-based Magnets,   2004 10 , IX th International Conference on Molecule-based Magnets
    • Syntheses and structures of rhodium and iridium complexes with polycyclic aromatic hydrocarbon ligands,   2004 09
    • Syntheses and crystal structures of novel rhodium and iridium complexes with [2.2]paracyclophane, The 36th International Conference on Coordination Chemistry,   2004 07 , The 36th International Conference on Coordination Chemistry
    • A Novel Mn12 Single-Molecule Magnet [Mn12O12(OAc)12(dpp)4], 36th International Conference on Coodination Chemistry,   2004 07 , 36th International Conference on Coodination Chemistry
    • Structure and Function of Silver Ⅰ Coordination Polymer with Aromatic Compounds,   2003 09
    • Synthesis, Structure and Property of Porous Copper Ⅰ Complexes,   2003 09
    • Synthesis and magnetic property of Mn12 Single-Molecule Magnets with phosphinate bridge,   2003 09
    • Synthesis and magnetic property of Mn Ⅲ -phthalocyanate and its derivatives,   2003 09
    • Structure and Photochromism of Silver Ⅰ Complexes with Diarylethene Derivative having Two Pyridyl Groups,   2003 09
    • Syntheses, Structures and Photochromic Behaviors of Silver Ⅰ Coordination Polymers with Ring-closed Diarylethene,   2003 09
    • Synthesis and magnetic property of a novel Mn12 complex partially substituted by 2.aminopyridine,   2003 09
    • Synthesis and magnetic property of a novel Mn4 complex with coordination of 1,10-phenanthroline,   2003 09
    • Synthesis and Structure of Porous Two-Dimensional CopperⅠComplexes with Dithiaparacyclophane,   2003 03
    • Mn12 Single.Molecule Magnets With Extended π.Conjugated Carboxylate Bridges,   2003 03
    • Structural characterization of novel iridium complexes with polydentate nitrogen ligands in solution and in the solid state,   2003 03
    • Synthesis of Photochromic Dinuclear RhodiumⅡComplexes with Bisthienyl Maleimide.,   2003 03
    • Structure and properties of silverⅠcoordination polymer with thiophenyl substituted aromatic compound,   2003 03
    • Sythesis and Magnetic Property of a Novel Mn12 Complex brigded by Methylenediphosphonic acid.,   2003 03
    • Structures and Magnetic properties of a neutral and anionic Mn12 complexes bridged by 2.thiophenecarboxylic acid,   2003 03
    • Novel Mn12 Single-Molecule Magnets With Methanesulfonate or Diphenyl-phosphate Bridges,   2002 10
    • Structure and photo-induced property of Silver(I) coordination polymer with benzyl groups,   2002 10
    • Structures and magnetic properties of nobel Mn12 single-molecule magnets with oxo bridges,   2002 10
    • Syntheses of silverⅠcoordination polymer with 1,4,5,8?tetrathioether group substituted naphthalene ligand,   2002 10
    • Synthesis and Structure of Porous CopperⅠComplexes with Dithi-aparacyclophane,   2002 09
    • Structures and magnetic properties of nobel Mn12 single-molecule magnets with oxo bridges,   2002 09
    • Structures and magnetic properties of Mn12 single-molecule magnets with extended π?conjugated carboxylic acids,   2002 09
    • Syntheses and magnetic properties of iron complexes with extended π?conjugated Schiff-base ligands,   2002 09
    • Syntheses, structures and reactivity of novel iridiumⅢhydrido complexes with multidentate nitrogen ligands,   2002 09
    • Synthesis, crystal structure, and magnetic property of a novel Mn12 single-molecule magnet with diphenylphosphate bridges,   2002 09
    • Synthesis of Photochromic Metal Complex with 1,2?Bis[4?methyl?2?(2?pyridyl)?5?thiazolyl]perfluorocyclopentene,   2002 09
    • Syntheses and magnetic properties of Mn12 single-molecule magnets with Schiff-base ligands,   2002 09
    • Structures and Photochromism of cis?1,2?Dicyano?1,2?bis(2,4,5?trimethyl?3?thienyl)ethene?Diruthenium(Ⅱ,Ⅲ)Complex,   2002 09
    • Synthesis and structure of novel rhodium and iridium complex with [2. 2] paracyclophane,   2002 09
    • Syntheses and crystal structures of mononuclear [2. 2] paracyclophane com-plexes of rhodium and iridium supported by the pentamethylcyclopentadienyl ligand [M(η6?pcp)(η6?C5Me5)] (BF4)2 (M=Rh and Ir),   2002 07
    • Crstal structure and photo?induced property of one, two?dimensional silverⅠcomplexes with poly(benzylsulfanyl)benzene,   2002 07
    • A NOVEL Mn12 SINGLE-MOLECULE MAGNET WITH DIPHENYL-PHOSPHATE BRIDGES,   2002 07
    • Solvent-dependent formation of di- and trinuclear rhodium and iridium complexes bridged by N, N donor ligands,   2002 03
    • The magnetic property of Fe-complexes coordinated by Schiff base ligand with extended π system,   2002 03
    • Magnetic property of Mn12 complexes bridged by carboxylates with extended π conjugated system,   2002 03
    • Structure and thermal transition behavior of tiophenyl substituted aromatic compound,   2002 03
    • Synthesis of Photochromic Molybdenum Complexes with Bis (thienyl) maleimide,   2002 03
    • Structure and properties of copper complex with thiophenylether substituted aromatic ligands,   2002 03
    • Structure and Magnetic Property of Novel Mn12 Nuclear Complex Partially Substituted by Diphenylphosphate,   2002 03
    • Structuers and Physical Properties of Copper Iodine Mixed-metal Complex Polymers Bridged by Dithiocarbamate Complex,   2002 03
    • Structure and Photochromism Dimolybdenum Complex and Dirhodium Complexes with cis 1, 2 Dicyano 1, 2 Bis (2, 4, 5 Trimethyl 3 Thienyl) Ethene,   2002 03
    • Efects of Metal Complexes and Antimicrobial Conpounds on Longevity of Cut-Gerbera Flowers,   2002 03
    • Syntheses of metal complexes with star-burst molecule consisting of π electron system,   2002 03
    • Search for Ethylene Binding Protein as a Marker of Ag Ions,   2002 03
    • Synthesis and structure of novel rhodium and iridium complex with [2.2] paracyclophane,   2001 09
    • Physical propertis of Mn12 complexes with basic carboxylic bridges,   2001 09
    • Syntheses and structures of novel iridium complexes bridged by multidentate nitrogen ligands,   2001 09
    • The Synthesis of 1 D Cu/Au Mixed Metal Complex Polymer,   2001 09
    • Synthesis and structure of silver coordination polymer with thiobenzylether group substituted aromatic compounds,   2001 09
    • Synthesis and properties of copper coordination polymer with thiophenylether group substituted aromatic compounds,   2001 09
    • Synthesis of Silver π Complexes with Diphenyl Derivatives,   2001 09
    • Syntheses and Structures of Cu Complex Polymers Bridged by Dithiolato Complexes,   2001 09
    • Structure and Photochromism of cis 1, 2 Dicyano 1, 2 bis (2, 4, 5 trimethyl 3 thienyl) ethene Dinuclear Molybdenum Complexes,   2001 09
    • Syntheses and structures of novel iridium complexes with terphenyl,   2001 09
    • Synthesis of Silver Complex Derived from 2, 3 Bis (2, 4, 5 trimethyl 3 thienyl) maleic anhydride,   2001 09
    • Synthesis and structure of metal coordination polymer with trinaphthene derivatives,   2001 03
    • Triple-decker, Spiral and Herringbone Silver ■ Complexes of Benzopyrene and the Derivatives,   2001 03
    • Synthesis of Photochromic Silver ■ Complexes with Bisthienylmaleic Anhydride,   2001 03
    • Synthesis and Structure of Three Dimensional Silver ■ p Complexes with Biphenylene,   2001 03
    • Effect of Silver■ Complexes on Ethylene-Promoted Flower Blooming and Longevity ■ : Ethylene Activity Inhibition,   2001 03
    • Optical and magnetic properties of a charge-transfer complex between a Mn12 single-molecule magnet and a TTF derivative,   2001 03
    • Syntheses and structures of rhodium and iridium paracyclophane complexes with Cp* as a support ligand,   2001 03
    • Syntheses and structures of di and trinuclear iridium complexes bridged by 4, 4′ bipyridine analogues,   2001 03
    • Synthesis and structure of metal coordination polymer with piezochromism,   2001 02

    Misc

    • Valence tautomeric behavior of tri-nuclear mixed-valence CoIII/CoII complex containing 2,3,6,7,10,11-hexahydroxytriphenylene (H6L), Y. Suenaga, M. Inomata, S. Yabumoto, R. Yamaguchi, T. Okubo, M. Maekawa, T. Kuroda-Sowa, 近畿大学理工学研究所研究報告, 30, 1, 10,   2018
    • Synthesis and Crystal Structures of New Mixed-Metal 1-D Coordination Polymers including a Copper-Iodide Cluster Unit, K. Tanshima, H. Anma, T. Okubo, M. Maekawa, T. Kuroda-Sowa, Annual reports by Research Institute for Science and Technology, 29, 11, 16,   2017
    • Carrier transport properties of copper-phthalocyanine thin films based on impedance spectroscopy, K. Himoto, T. Okubo, M. Maekawa, T. Kuroda-Sowa, 近畿大学理工学総合研究所研究報告, 27, 43, 48,   2015
    • Synthesis and carrier transport properties of a new mixed-valence 1-D coordination polymer with an isopropyl dithiocarbamate ligand, Y. Nakahashi, S. Suzuki, Y. Ota, T. Okubo, M. Maekawa, T. Kuroda-Sow, 近畿大学理工学総合研究所研究報告, 27, 34, 42,   2015
    • Role of bulky thiophenylether substituted aromatic compounds as a linker in porous silver(I) coordination polymers, Y. Suenaga, S. Ueda, Y. Umehata, M. Maekawa, 近畿大学理工学総合研究所研究報告, 27, 25, 34,   2015
    • The observation of isocyano cobalt(III)-Schiff base complexes,, Z. Yu, T. Kuroda-Sowa, A. Okamoto, A. Nabei, T. Okubo, M. Maekawa, 近畿大学理工学総合研究所研究報告, 25, 11, 19,   2013
    • Synthesis of a New Mixed-valence DecanuclearCu(I)-Cu(II) Cluster with a Hexamethylene Dithiocarbamate Ligand, T. Okubo, N. Tanaka, M. Maekawa, Takayoshi Kuroda-Sowa, 近畿大学理工学総合研究所研究報告, 24, 53, 57,   2012
    • Application of mononuclear metal complexes with a hexamethylene-dithiocarbamate ligand as photosensitizers for dye-sensitized solar cells, K.-H. Kim, Y. Inuzuka, T. Okubo, M. Maekawa, T. Kuroda-Sowa, 近畿大学理工学総合研究所研究報告, 23, 19, 22,   2011
    • Syntheses, crystal structures and electrochemical properties of bis(catechol)s with acetylene group, Y. Suenaga, Y. Hirano, Y. Umehata, K. Kamei, M. Maekawa, 近畿大学理工学総合研究所研究報告, 23, 23, 33,   2011

    Research Grants & Projects

    • Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Self-assembly of novel metallamacrocycles as a functional anion receptors