Performance information

• Low-dimensional magnetic properties of the ladder-like polynuclear complex Cu2(naphac)2(OH)2 (naphac = 3-(1-naphthyl)acrylate)　　　　　　　　　　　　　　　
  Zentaro Honda; Takashi Fujihara; Takanori Kida; Masayuki Hagiwara
  Physica B: Condensed Matter, First page：416254, Last page：416254, Jun. 2024
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/j.physb.2024.416254
  DOI ID：10.1016/j.physb.2024.416254, ISSN：0921-4526
• Cyclometalated Platinum(II) Complexes in a Cis-N,N Configuration: Photophysical Properties and Isomerization to Trans Isomers
  Keiji Ohno; Kazuki Shiraishi; Tomoaki Sugaya; Akira Nagasawa; Takashi Fujihara
  Inorganic Chemistry, Volume：61, Number：8, First page：3420, Last page：3433, Feb. 2022
  American Chemical Society (ACS), Scientific journal
  DOI：https://doi.org/10.1021/acs.inorgchem.1c03295
  DOI ID：10.1021/acs.inorgchem.1c03295, ISSN：0020-1669, eISSN：1520-510X
• Substituent effect on emission of flavonolate-boron difluoride complexes: The role of π-system for dual-state (solution and solid) emission　　　　　　　　　　　　　　　
  Keiji Ohno; Fuka Narita; Hidehisa Yokobori; Nanami Iiduka; Tomoaki Sugaya; Akira Nagasawa; Takashi Fujihara
  Dyes and Pigments, Volume：187, First page：109081, Last page：109081, Mar. 2021, [Reviewed]
  Elsevier {BV}, English, Scientific journal
  DOI：https://doi.org/10.1016/j.dyepig.2020.109081
  DOI ID：10.1016/j.dyepig.2020.109081, ISSN：0143-7208, ORCID：96736411
• Large magnetic anisotropy in a quasi-1D ferromagnetic complex Co(sba)(H2O)2·H2O (sba = 4-sulfobenzoate)　　　　　　　　　　　　　　　
  Naoyuki Nomoto; Takashi Fujihara; Norihiko Kamata; Yuya Sawada; Takanori Kida; Masayuki Hagiwara; Zentaro Honda
  Journal of Solid State Chemistry, Volume：290, First page：121527, Last page：121527, Oct. 2020
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/j.jssc.2020.121527
  DOI ID：10.1016/j.jssc.2020.121527, ISSN：0022-4596
• o-Azophenylboronic Acid-Based Colorimetric Sensors for d-Fructose: o-Azophenylboronic Acids with Inserted Protic Solvent Are the Key Species for a Large Color Change　　　　　　　　　　　　　　　
  Yota Suzuki; Ayumi Ikeda; Keiji Ohno; Takashi Fujihara; Tomoaki Sugaya; Koji Ishihara
  The Journal of Organic Chemistry, Aug. 2020, [Reviewed]
  American Chemical Society ({ACS}), Scientific journal
  DOI：https://doi.org/10.1021/acs.joc.0c01011
  DOI ID：10.1021/acs.joc.0c01011, ORCID：77728778
• Spin-inversion mechanisms in O2 binding to a model heme complex revisited by density function theory calculations　　　　　　　　　　　　　　　
  Kohei Saito; Yuya Watabe; Takashi Fujihara; Toshiyuki Takayanagi; Jun-ya Hasegawa
  Journal of Computational Chemistry, Volume：41, Number：11, First page：1130, Last page：1138, Apr. 2020
  Spin-inversion mechanisms in O2 binding to a model heme complex, consisting of Fe(II)-porphyrin and imidazole, were investigated using density-functional theory calculations. First, we applied the recently proposed mixed-spin Hamiltonian method to locate spin-inversion structures between different total spin multiplicities. Nine spin-inversion structures were successfully optimized for the singlet–triplet, singlet–quintet, triplet–quintet, and quintet–septet spin-inversion processes. We found that the singlet–triplet spin-inversion points are located around the potential energy surface region at short Fe–O distances, whereas the singlet–quintet and quintet–septet spin-inversion points are located at longer Fe–O distances. This suggests that both narrow and broad crossing models play roles in O2 binding to the Fe-porphyrin complex. To further understand spin-inversion mechanisms, we performed on-the-fly Born-Oppenheimer molecular dynamics calculations. The reaction coordinates, which are correlated to the spin-inversion dynamics between different spin multiplicities, are also discussed.
  John Wiley and Sons Inc., English, Scientific journal
  DOI：https://doi.org/10.1002/jcc.26159
  DOI ID：10.1002/jcc.26159, ISSN：1096-987X, PubMed ID：32020659, SCOPUS ID：85078919630
• Luminescence of mononuclear Pt(ii) complexes with glycolate: external stimuli-induced excimer emission changes to oligomer emissions　　　　　　　　　　　　　　　
  Keiji Ohno; Masaya Komuro; Tomoaki Sugaya; Akira Nagasawa; Takashi Fujihara
  Dalton Transactions, 2020, [Reviewed]
  Royal Society of Chemistry ({RSC}), Scientific journal
  DOI：https://doi.org/10.1039/C9DT03996A
  DOI ID：10.1039/C9DT03996A, ORCID：67685829
• Computational Analysis of Two-State Reactivity in β-Hydride Elimination Mechanisms of Fe(II)– and Co(II)–Alkyl Complexes Supported by β-Diketiminate Ligand
  Organometallics, Oct. 2019, [Reviewed]
  DOI：https://doi.org/10.1021/acs.organomet.9b00418
  DOI ID：10.1021/acs.organomet.9b00418, ORCID：61488602
• The First Bis(μ-acetato)(μ-oxido)diruthenium(III) Complexes with Sulfur Donor Ligands　　　　　　　　　　　　　　　
  Yohei Ido; Takashi Fujihara; Tomoaki Sugaya; Akira Nagasawa
  ChemistrySelect, Volume：4, Number：33, First page：9696, Last page：9702, Aug. 2019, [Reviewed]
  WILEY-VCH Verlag GmbH & Co. KGaA, English, Scientific journal
  DOI：https://doi.org/10.1002/slct.201901821
  DOI ID：10.1002/slct.201901821
• A water-soluble cyclometalated iridium(iii) complex for pH sensing based on aggregation-induced enhanced phosphorescence
  Keiji Ohno; Tetuya Sakata; Machi Shiiba; Akira Nagasawa; Takashi Fujihara
  Dalton Transactions, 2019, [Reviewed]
  Royal Society of Chemistry ({RSC})
  DOI：https://doi.org/10.1039/C8DT04861D
  DOI ID：10.1039/C8DT04861D, ORCID：55496070
• Cover Feature: Observation of the First Spin Crossover in an Iron(II) Complex with an S 6 Coordination Environment: Tris[bis( N , N ‐diethylamino)carbeniumdithiocarboxylato]iron(II) Hexafluorophosphate (Chem. Eur. J. 68/2018)
  Tomoaki Sugaya; Takashi Fujihara; Takashi Naka; Takao Furubayashi; Akiyuki Matsushita; Hiroaki Isago; Akira Nagasawa
  Chemistry – A European Journal, Dec. 2018, [Reviewed]
  Wiley
  DOI：https://doi.org/10.1002/chem.201805312
  DOI ID：10.1002/chem.201805312, ORCID：51622016
• Single-step preparation of topological gels using vinyl-modified -cyclodextrin as a figure-of-six cross-linker　　　　　　　　　　　　　　　
  Yuki Kobayashi; Yu Kojima; Ryotaro Miki; Toshinobu Seki; Takashi Fujihara; Yoshihiro Ishimaru; Yuya Egawa
  JOURNAL OF INCLUSION PHENOMENA AND MACROCYCLIC CHEMISTRY, Volume：92, Number：3-4, First page：311, Last page：317, Dec. 2018, [Reviewed]
  Herein, we have proposed a single-step preparation of topological gels using vinyl-modified -cyclodextrin (V--CyD) and isoprene. Copolymerization of V--CyD and isoprene in an aqueous solution resulted in gelation due to V--CyD acting as a novel type of copolymer chain cross-linker. The vinyl moiety of V--CyD becomes a part of the copolymer, while the -CyD moiety of V--CyD simultaneously incorporates the isoprene component of the copolymer. V--CyD is capable of two different modes of cross-linking at each end, i.e., chemically bonding and mechanically interlocking. Due to the shape of the cross-linking point, we refer to it as figure-of-six cross-linking. Nuclear magnetic resonance analysis showed that the gel contained V--CyD and isoprene in an approximately 1:0.3 stoichiometry. The relatively high content of -CyD was reflected in the character of the gel; the gel swelled in dimethylformamide which is a good solvent of -CyD. A fluorometric analysis using 6-(p-toluidino)-2-naphthalenesulfonic acid showed that the appended -CyD was able to accommodate guest molecules. Introduction of an additional vinyl monomer into the gel was also successful. Addition of 4-vinylphenylboronic acid to the preparation procedure yielded a sugar-responsive gel that swelled in the presence of d-fructose.
  SPRINGER, English, Scientific journal
  DOI：https://doi.org/10.1007/s10847-018-0852-7
  DOI ID：10.1007/s10847-018-0852-7, ISSN：1388-3127, eISSN：1573-1111, ORCID：51094813, Web of Science ID：WOS:000451049300007
• Observation of the First Spin Crossover in an Iron(II) Complex with an S 6 Coordination Environment: Tris[bis( N , N ‐diethylamino)carbeniumdithiocarboxylato]iron(II) Hexafluorophosphate
  Tomoaki Sugaya; Takashi Fujihara; Takashi Naka; Takao Furubayashi; Akiyuki Matsushita; Hiroaki Isago; Akira Nagasawa
  Chemistry – A European Journal, Dec. 2018, [Reviewed]
  Wiley
  DOI：https://doi.org/10.1002/chem.201803330
  DOI ID：10.1002/chem.201803330, ORCID：51048314
• Chromism of Tartrate-Bridged Clamshell-like Platinum(II) Complex: Intramolecular Pt–Pt Interaction-Induced Luminescence Vapochromism and Intermolecular Interactions-Triggered Thermochromism
  Keiji Ohno; Yukiko Kusano; Sumio Kaizaki; Akira Nagasawa; Takashi Fujihara
  Inorganic Chemistry, Nov. 2018, [Reviewed]
  American Chemical Society ({ACS})
  DOI：https://doi.org/10.1021/acs.inorgchem.8b02074
  DOI ID：10.1021/acs.inorgchem.8b02074, ORCID：49948458
• Electron transfer kinetics of methylviologen included in 4-sulfonatocalix[n]arenes at glassy carbon electrode; adiabaticity and activation energy　　　　　　　　　　　　　　　
  Takahashi Yuki; Fujihara Takashi; Kobayashi Naritaka; Nakabayashi Seiichiro; Miskolczy Zsombor; Biczok Laszlo
  Chemical Physics Letters, Volume：708, First page：222, Last page：227, 2018, [Reviewed]
  DOI：https://doi.org/10.1016/j.cplett.2018.08.005
  DOI ID：10.1016/j.cplett.2018.08.005, ORCID：49468474, Web of Science ID：WOS:000443278800037
• One-dimensional ferromagnetic array compound [Co3(SBA)2(OH)2(H2O)2]n, (SBA = 4-sulfobenzoate)
  Zentaro Honda; Naoyuki Nomoto; Takashi Fujihara; Masayuki Hagiwara; Takanori Kida; Yuya Sawada; Takeshi Fukuda; Norihiko Kamata
  Solid State Sciences, Volume：80, First page：155, Last page：160, 2018, [Reviewed]
  DOI：https://doi.org/10.1016/j.solidstatesciences.2018.04.003
  DOI ID：10.1016/j.solidstatesciences.2018.04.003, ORCID：49055449
• Safe and rapid development of capillary electrophoresis for ultratrace uranyl ions in radioactive samples by way of fluorescent probe selection for actinide ions from a chemical library
  Tomoko Haraga; Kazuki Ouchi; Yoshiyuki Sato; Hitoshi Hoshino; Rei Tanaka; Takashi Fujihara; Hideki Kurokawa; Masami Shibukawa; Ken-ichiro Ishimori; Yutaka Kameo; Shingo Saito
  Analytica Chimica Acta, Volume：1032, First page：188, Last page：196, 2018, [Reviewed]
  After the serious nuclear accident at the Fukushima Daiichi Nuclear Power Plant caused by the Great East Japan Earthquake in 2011, the development of feasible, safe, and highly sensitive analytical methods (in terms of low levels of radiation exposure and radioactive waste generation) for radioactive samples, especially actinide (An) ions, represents an important challenge. Here we propose a methodology for selecting appropriate emissive probes for An ions with very low consumption and emission of radioactivity by capillary electrophoresis–laser-induced fluorescence detection (CE-LIF), using a small chemical library of probes with eight different chelating moieties. It was found that the emissive probe L1, which possesses the tetradentate chelating moiety 1,10-phenanthroline-2,9-dicarboxylic acid (PDA), was suitable for detecting uranyl ions. The detection limit for the uranyl–L1 complex using CE-LIF combined with dynamic ternary complexation and on-capillary concentration techniques was determined to be 2.9 × 10−12 M (0.7 ppt). No interference from the large excess of matrix metal ions was observed. This method was successfully applied to real radioactive liquid samples collected from nuclear facilities, including the Fukushima Daiichi Nuclear Power Plant. This strategy not only permitted the development of a safe and rapid analytical method but also provided insight into the coordination chemistry of An ion complexes. Specifically, the PDA structure provided substantial kinetic inertness to its uranyl complex
  the formation of a ternary complex between uranyl–L1 and carbonate was revealed
  and unusual interactions were observed between the π-electron systems of uranyl and the phenanthroline ring, which stabilized the uranyl–PDA interaction.
  Elsevier B.V., English, Scientific journal
  DOI：https://doi.org/10.1016/j.aca.2018.05.077
  DOI ID：10.1016/j.aca.2018.05.077, ISSN：1873-4324, ORCID：49055441, SCOPUS ID：85048477881
• Syn and anti conformers of diammonium aquabis(malonato)oxidovanadate(IV) in an anhydrate crystal
  Keiji Ohno; Takumi Yoshida; Akira Nagasawa; Takashi Fujihara
  Acta Crystallographica Section E: Crystallographic Communications, Volume：74, Number：5, First page：664, Last page：667, 2018, [Reviewed]
  The asymmetric unit of the title anhydrate compound, (NH4)2 [VO(C3 H2 O4)2 (H2 O)], consists of two independent complex anions and four ammonium cations. In the complex anions, the V IV atoms are each coordinated by two malonate ligands, one water molecule and one oxide O atom in a distorted octahedral geometry. The equatorial plane is formed by the malonate O atoms, while the axial positions are occupied by water and oxide O atoms. The difference between the two independent complexes is the relative conformation of the malonate ligands. The two ligands in one complex anion are in a syn conformation, while in the other they adopt an anti conformation. In the crystal, the complex anions interact with the counter-cations and adjacent anions through O - H...O, N - H...O and C - H...O hydrogen bonds. Stacks of alternating layers consisting of either anti or syn isomers, formed with the aid of the hydrogen bonding, are observed. DFT calculations for the anti and syn isomers show a similar thermodynamic stability to each other. The crystal used for this analysis was an inversion twin with the ratio of the twin components being 0.270 (13):0.730 (13).
  International Union of Crystallography, English, Scientific journal
  DOI：https://doi.org/10.1107/S2056989018005686
  DOI ID：10.1107/S2056989018005686, ISSN：2056-9890, ORCID：43712858, SCOPUS ID：85046789915
• A polyrotaxane gel using boronic acid-appended γ-cyclodextrin as a hybrid cross-linker　　　　　　　　　　　　　　　
  Wataru Uchida; Maiki Yoshikawa; Tomohiro Seki; Ryotaro Miki; Toshinobu Seki; Takashi Fujihara; Yoshihiro Ishimaru; Yuya Egawa
  Journal of Inclusion Phenomena and Macrocyclic Chemistry, Volume：89, Number：3-4, First page：281, Last page：288, Dec. 2017, [Reviewed]
  © 2017, Springer Science+Business Media B.V. A boronic acid-appended γ-cyclodextrin (BA-CyD) was synthesized as a hybrid cross-linker of polyvinyl alcohol (PVA) to form a new type of hydrogel. The CyD moiety of BA-CyD forms an inclusion complex with the PVA chain to produce a mechanically interlocking structure. At the same time, the BA moiety of BA-CyD forms covalent bonds with the 1,3-diol moieties of PVA. On the basis of these two modes of interaction, the hybrid cross-linker connects two PVA chains, thus resulting in the formation of a hydrogel. To investigate the possibility of this hydrogel becoming the basis for an intelligent material for drug delivery, sugar-responsive drug release from the hydrogel was demonstrated.
  Scientific journal
  DOI：https://doi.org/10.1007/s10847-017-0755-z
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85033486758&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=85033486758&origin=inward
  DOI ID：10.1007/s10847-017-0755-z, ISSN：0923-0750, eISSN：1573-1111, SCOPUS ID：85033486758
• Change in Luminescence Induced by Solution-Mediated Phase-Transition of Cyclometalated Platinum(II) Complex with Isoquinoline Carboxylate　　　　　　　　　　　　　　　
  Keiji Ohno; Mami Hasebe; Akira Nagasawa; Takashi Fujihara
  INORGANIC CHEMISTRY, Volume：56, Number：20, First page：12158, Last page：12168, Oct. 2017, [Reviewed]
  Changes in luminescence due to solution-mediated phase transition (SMPT) and crystal-to-crystal phase transitions of a novel cyclometalated platinum(II) complex with isoquinoline-1-carboxylate (Iq-1-COO-) [Pt(bzq)(Iq-1-COO)] (bzq(-) : benzoquinolinate) were studied experimentally and theoretically. Recrystallization of the complex allowed three crystal forms depending on the solvent: red polymorph R-DMF (lambda(emi) = 689 nm), yellow polymorph Y-DMSO (lambda(emi) = 641 nm), and red pseudopolymorph RBCHCl3 (lambda(emi) = 721 nm). Crystals of R-DMF in the DMF solution at room temperature showed SMPT to yellow crystals Y-DMF (lambda(emi) = 627 nm), in which R-DMF first dissolved partly into the solution, and then the dissolved complex crystallized as Y-DMF. RBCHCl3 exhibited crystal-to-crystal phase transitions to R-DMF and Y-DMF by being heated to 150 degrees C and stored in atmospheric conditions, respectively. Molecular structures of each of the four crystal forms, analyzed by X-ray crystallography, showed different planarities because of the dihedral angles between the bzq(-) and Iq planes being 3.15, 4.80, 8.35, and 17.7 degrees for RBCHCl3, R-DMF, Y-DMSO, and Y-DMF, respectively. The planar complexes in R-DMF and RBCHCl3 constructed dieters through intermolecular Pt-Pt and pi-pi interactions, whereas the distorted complexes in Y-DMF and Y-DMSO remained as monomers. Density functional theory (DFT) calculations, which reveal the relation between the molecular structure and thermodynamic stability, suggest that the SMPT is triggered by thermodynamic transformation from the metastable planar structure to the stable distorted structure. The intradimer interactions in R-DMF and RBCHCl3 induced red-shifts in the absorption and emission colors from those of Y-DMF and Y-DMSO; thus, the photophysical properties of RBCHCl3 and R-DMF originate from the MMLIqCT state in contrast with the MLIqCT/LbzqLIqCT character for Y-DMF and Y-DMSO. DFT and time-dependent DFT (TD-DFT) calculations in the ground and excited states provide insight into the structural, electronic, and optical properties.
  AMER CHEMICAL SOC, English, Scientific journal
  DOI：https://doi.org/10.1021/acs.inorgchem.7b01466
  DOI ID：10.1021/acs.inorgchem.7b01466, ISSN：0020-1669, eISSN：1520-510X, ORCID：37343408, Web of Science ID：WOS:000413279300011
• Luminescence of tartrate bridged dinuclear 2,2 '-bipyridine platinum(II) complexes: emission color controlled by intra- and inter-molecular interactions in the solid state　　　　　　　　　　　　　　　
  Keiji Ohno; Honami Tanuma; Yukiko Kusano; Sumio Kaizaki; Akira Nagasawa; Takashi Fujihara
  DALTON TRANSACTIONS, Volume：46, Number：23, First page：7612, Last page：7618, Jun. 2017, [Reviewed]
  Novel dinuclear Pt-II complexes with a chiral (L-) and an achiral (meso-) tartrate [{Pt-II(bpy)}(2)(mu-x-tart)] (bpy: 2,2'-bipyridine; tartH(2)(2-): tartrate; x = L (1), meso (2)) and with a racemic (DL-) tartrate [{Pt-II(bpy)}(2)(mu-D-tart)][{Pt-II(bpy)}(2)(mu-L-tart)] (3) were synthesized, and the influence of their stereochemistry on their molecular and crystal structures affecting their luminescence was discussed. Effects of the dinuclearity on the structures and luminescence were revealed by comparison with those of a novel racemic mononuclear complex [PtII(bpy)(D-tartH(2))][Pt-II(bpy)(L-tartH(2))] (4). The X-ray crystallography showed the crystallization of 1 in two polymorphs, namely monoclinic 3[1.6H(2)O] (1 alpha) and triclinic 2[1.6H(2)O] (1 beta), and those of other complexes in monoclinic hydrate crystals 2.12.5H(2)O, 3.4H(2)O, and 4.H2O. The chiral complexes in 1 alpha, 1 beta, and 3.4H(2)O showed clamshell-like structures with Pt-Pt and pi-pi interactions, while the achiral complex in 2.12.5H(2)O displayed a twisted form without intramolecular interactions. The complexes in 1 alpha were assembled in a right-handed helical arrangement through significant Pt-Pt interactions, and those in 1 beta and 3.4H(2)O were stacked in one-dimensional columns through significant and slight pi-pi interactions, respectively. The complex in 2.12.5H(2)O constructed an intermolecular dimer through Pt-Pt interactions with its adjacent complex. The crystal structure of 4.H2O displayed a three-dimensional network architecture through pi-pi interactions and hydrogen bonding. These crystals exhibited luminescence depending on their molecular and crystal structures (lambda(max) nm = 535 (4.H2O), 569 (3.4H(2)O), 621 (2.12.5H(2)O), 649 (1 beta), and 656 (1 alpha)). The formations of intermolecular dimers and clamshell-like structures through Pt-Pt interactions in 2.12.5H(2)O and in 3.4H(2)O, respectively, lead to red-shifts in emissions compared to 4.H2O, and further low-energy emissions of 1 alpha and 1 beta were derived from the intermolecular Pt-Pt and pi-pi interactions, respectively.
  ROYAL SOC CHEMISTRY, English, Scientific journal
  DOI：https://doi.org/10.1039/c7dt00745k
  DOI ID：10.1039/c7dt00745k, ISSN：1477-9226, eISSN：1477-9234, Web of Science ID：WOS:000403436200028
• A red fluorophore comprising a borinate-containing xanthene analogue as a polyol sensor　　　　　　　　　　　　　　　
  下村 有輝; 江川 祐哉; 三木 涼太郎; 藤原 隆司; 石丸 雄大; 関 俊暢
  Organic & biomolecular chemistry, Volume：2016, Number：14, First page：10031, Last page：10036, 2016
  A xanthene derivative containing a borinate moiety emitted red fluorescence with a high quantum yield. The interaction between the borinate and a sugar molecule induced a fluorescence change based on the change in the HOMO–LUMO gap. The response was pH-resistant in a wide range. In addition, catechol quenched through photoinduced electron transfer. The red fluorescence and polyol binding ability of dyes will pave the way for new biological applications of chemical sensors.Open Access Article
  Royal Society of Chemistry, English
  DOI：https://doi.org/10.1039/c6ob01695b
  DOI ID：10.1039/c6ob01695b, ISSN：1477-0520, CiNii Articles ID：120005960911, CiNii Books ID：AA1168650X
• Mechanochromism in the luminescence of novel cyclometalated platinum(II) complexes with alpha-aminocarboxylates　　　　　　　　　　　　　　　
  Keiji Ohno; Shohei Yamaguchi; Akira Nagasawa; Takashi Fujihara
  DALTON TRANSACTIONS, Volume：45, Number：13, First page：5492, Last page：5503, 2016, [Reviewed]
  Six novel phosphorescent cyclometalated platinum(II) complexes with alpha-aminocarboxylato ligands, [Pt-II(ppy) L] (ppy = 2-phenylpyridinato, L-= Gly, Ala, Leu, Ile, Phe, Sar), were synthesized, and the structures were determined by X-ray crystallography. [Pt-II(ppy) L] (L-= Gly, Ala) in crystals are in monomeric structures and stack through pi-pi interactions to form columns, and the features of the luminescence are similar to each other and those in solution, suggesting little influence of the pi-pi interactions on the luminescence. [Pt-II(ppy) Leu] has a dimeric structure through the Pt-Pt interaction. [Pt-II(ppy) Sar] showed two pseudo-polymorphs, one of which contains both monomeric and dimeric forms, while the other consists of only dimeric units. Intra-dimer pi-pi interactions were observed in both the dimeric units. [Pt-II(ppy) L] (L-= Leu, Ile, Phe) in the solid state displayed different spectral patterns of luminescence from those in solution, suggesting that the dimeric structures through the Pt-Pt interaction in the solid state are dissociated into the corresponding monomeric ones in solution. The complexes except [Pt-II(ppy) Phe] in the solid state exhibited reversible luminescent mechanochromism in response to the mechanical grinding and treatment with a few drops of solvent. These phenomena are induced by the change in the energy level of the triplet state due to the change in the extent of intermolecular interactions, which appeared due to the crystalline-amorphous phase conversion.
  ROYAL SOC CHEMISTRY, English, Scientific journal
  DOI：https://doi.org/10.1039/c5dt04516a
  DOI ID：10.1039/c5dt04516a, ISSN：1477-9226, eISSN：1477-9234, Web of Science ID：WOS:000372608300012
• Synthesis and Antiaromatic Properties of Highly Planar Dithiaamethyrin　　　　　　　　　　　　　　　
  Yoshihiro Ishimaru; Naoyuki Shimoyama; Takashi Fujihara; Keigo Watanabe; Jun-ichiro Setsune
  CHEMISTRY-AN ASIAN JOURNAL, Volume：10, Number：2, First page：329, Last page：333, Feb. 2015, [Reviewed]
  2,5-Bis(4-propyl-2-pyrrolyl) thiophene was reacted with aryl aldehydes to afford large porphyrinoids; [24]dithiaamethyrin(1.0.0.1.0.0) and [36]trithianonaphyrin(1.0.0.1.0.0.1.0.0). X-ray crystallography of the dithiaamethyrin revealed a highly planar ring structure with mean plane deviation (MPD) value of 0.053 angstrom. A large positive NICS(0) value (+13.9 ppm) calculated for this planar 24 pi system unambiguously indicates an antiaromatic character that is consistent with a remarkably low field H-1 chemical shift of the inner NH proton at 24.0 ppm. The magnitude of the paratropic ring current effect in the 24 pi amethyrin framework in the free base form and the diprotonated form was discussed on the basis of the MPD value and the NICS value. The present dithiaamethyrin is much more strongly antiaromatic than the dodecaalkylamethyrin in their free base forms, but the order inversed in their di-protonated forms.
  WILEY-V C H VERLAG GMBH, English, Scientific journal
  DOI：https://doi.org/10.1002/asia.201403126
  DOI ID：10.1002/asia.201403126, ISSN：1861-4728, eISSN：1861-471X, Web of Science ID：WOS:000348719500006
• Crystal Structure of the Spin 1=2 Honeycomb-Lattice Antiferromagnet Cu2(pymca)3(ClO4)　　　　　　　　　　　　　　　
  Zentaro Honda; Takafumi Kodama; Reo Kikukawa; Masayuki Hagiwara; Takanori Kida; Masamichi Sakai; Takeshi Fukuda; Takashi Fujihara; Norihiko Kamata
  Journal of the Physical Society of Japan, Feb. 2015, [Reviewed], [Invited]
  English, Scientific journal
  DOI：https://doi.org/10.7566/JPSJ.84.034601
  DOI ID：10.7566/JPSJ.84.034601
• Crystal structure of 4,4'-dimethoxy-2,2'-bipyridine　　　　　　　　　　　　　　　
  Yukiko Kusano; Keiji Ohno; Takashi Fujihara
  Acta Crystallographica Section E: Crystallographic Communications, Volume：71, First page：o623, Last page：o624, 2015, [Reviewed]
  In the title compound, C12H12N2O2, the dihedral angle between the planes of the two pyridine rings is 5.8 (1)°. Neighbouring molecules are linked via C(Me)-H···N interactions, generating a two-dimensional sheet structure
  C-H···π interactions further link the molecules into a three-dimensional network. An overlapped arrangement of parallel pyridine rings in neighbouring molecules [centroid-to-centroid distance = 3.6655 (15) Å] is observed in the crystal structure.
  International Union of Crystallography, English, Scientific journal
  DOI：https://doi.org/10.1107/S2056989015013985
  DOI ID：10.1107/S2056989015013985, ISSN：2056-9890, SCOPUS ID：84976476538
• Crystal structure of fac-trichlorido[tris(pyridin-2-yl-N)amine]chromium(III)　　　　　　　　　　　　　　　
  Yukiko Yamaguchi-Terasaki; Takashi Fujihara; Akira Nagasawa; Sumio Kaizaki; M. Weil
  Acta Crystallographica Section E: Structure Reports Online, Volume：71, Number：1, First page：73, Last page：75, Jan. 2015, [Reviewed]
  In the neutral complex molecule of the title compound, fac-[CrCl<
  inf>
  3<
  /inf>
  (tpa)] [tpa is tris(pyridin-2-yl)amine
  C<
  inf>
  15<
  /inf>
  H<
  inf>
  12<
  /inf>
  N<
  inf>
  4<
  /inf>
  ], the Cr<
  sup>
  III<
  /sup>
  ion is bonded to three N atoms that are constrained to a facial arrangement by the tpa ligand and by three chloride ligands, leading to a distorted octahedral coordination sphere. The average Cr - N and Cr - Cl bond lengths are 2.086 (5) and 2.296 (4) Å, respectively. The complex molecule is located on a mirror plane. In the crystal, a combination of C - H⋯N and C - H⋯Cl hydrogen-bonding interactions connect the molecules into a three-dimensional network.
  International Union of Crystallography, English, Scientific journal
  DOI：https://doi.org/10.1107/S2056989014027066
  DOI ID：10.1107/S2056989014027066, ISSN：1600-5368, SCOPUS ID：84928156017
• Dinuclear nickel(II) complexes with 2,5-diamino-1,4-benzoquinonediimine ligands as precatalysts for the polymerization of styrene: electronic and steric substituent effects　　　　　　　　　　　　　　　
  Keiji Ohno; Akira Nagasawa; Takashi Fujihara
  DALTON TRANSACTIONS, Volume：44, Number：1, First page：368, Last page：376, 2015, [Reviewed]
  Catalytic polymerization of styrene with a series of dinuclear nickel(II) complexes [{Ni(acac)}(2){mu-C6H2-(N-Ph-R)(4)}] (R = 4-Et (1a), 4-OEt (1b), 2-OEt (1c), 2-Et (1d), and 2,6-Et-2 (1e)) in the presence of methyl-aluminoxane was studied under various conditions to evaluate the substituent effect. The activity of 1a-1e, except 1c, increased with an increase in the reaction temperature, and the highest activity (7.46 x 10(5) g PS mol(-1) Ni h(-1)) was obtained using 1e at 70 degrees C. The electronic and steric properties of the ligand influenced the activity at room temperature, 50 degrees C, and 60 degrees C, steric factors barely, whereas electronic factors slightly dominated the activity at 70 degrees C. The activity with 1c remained constant at all temperatures, probably due to the masking of the active center by the formation of inactive N,N',O-chelate species. The obtained polymers were atactic polystyrenes with molecular weights and molecular weight distributions in the range of 15 000-43 400 and 1.71-2.14, respectively. While a clear dependence of the molecular weight and molecular weight distribution on the temperature was observed, no significant dependence on the substituent was noted.
  ROYAL SOC CHEMISTRY, English, Scientific journal
  DOI：https://doi.org/10.1039/c4dt02858a
  DOI ID：10.1039/c4dt02858a, ISSN：1477-9226, eISSN：1477-9234, Web of Science ID：WOS:000346408900045
• Preparation of polypseudorotaxanes composed of cyclodextrin and polymers in microspheres　　　　　　　　　　　　　　　
  Katsunori Shinohara; Miki Yamashita; Wataru Uchida; Chie Okabe; Shinji Oshima; Masahiro Sugino; Yuya Egawa; Ryotaro Miki; Osamu Hosoya; Takashi Fujihara; Yoshihiro Ishimaru; Tohru Kishino; Toshinobu Seki; Kazuhiko Juni
  Chemical and Pharmaceutical Bulletin, Volume：62, Number：10, First page：962, Last page：966, Oct. 2014, [Reviewed]
  © 2014 The Pharmaceutical Society of Japan. We prepared polypseudorotaxanes (PPRXs) composed of cyclodextrin (CyD) and polyethylene glycol (PEG) inside microspheres (MSs) by an emulsifying process using polypropylene glycol (PPG) that shows temperature-dependent hydrophilicity changes; PPG is hydrophobic at high temperatures but hydrophilic at low temperatures. An aqueous solution of CyD and PEG was dispersed as droplets in PPG at 60°C then cooled to 0°C to allow water of droplets to transfer into PPG. On removal of water in the droplets, CyD and PEG were left behind as a CyD/PEG PPRX inside the solid-state MSs. Examination of α-, β-, and γ-CyD revealed that α-CyD was suitable for the formation of PPRX containing PEG in this MS preparation procedure. Interestingly, a new PPRX composed of α-CyD and PPG was formed in the α-CyD MSs when they were prepared in the absence of PEG from the aqueous solution of α-CyD. This MS fabrication procedure can control the size and shape of PPRX particles, and will contribute to the production of new types of CyD inclusion complexes.
  Scientific journal
  DOI：https://doi.org/10.1248/cpb.c14-00313
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84908179531&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=84908179531&origin=inward
  DOI ID：10.1248/cpb.c14-00313, ISSN：0009-2363, eISSN：1347-5223, PubMed ID：25273055, SCOPUS ID：84908179531
• Formation of boron, nickel(II) and iridium(III) complexes with an azophenine derivative: Isomerization, delocalization and extension of the pi-conjugated system on coordination　　　　　　　　　　　　　　　
  Keiji Ohno; Takashi Fujihara; Akira Nagasawa
  POLYHEDRON, Volume：81, First page：715, Last page：722, Oct. 2014, [Reviewed]
  The azophenine N,N',N '',N'''-tetra-4-ethylpheny1-2,5-diamino-1,4-benzoquinonediimine (4-EtApH(2)), its diprotonated species [4-EtApH(4)](ClO4)(2) (1) and complexes, the bis(boron difluoride) complex (2), the mono- and dinuclear nickel(II) complexes (Ni(4-EtApH(2))(3)](ClO4)(2) (3) and [{Ni(acac)}2(R-4-EtAp)] (4), respectively, and the dinuclear iridium(III) complex [{Ir(cp*)Cl)(2)(mu-4-EtAp)] (5), have been prepared. The molecular structures of these compounds were determined by X-ray analysis. The coordination environments around the boron center of 2 and the Ni centers of 3 and 4 were tetrahedral, octahedral and square-planar, respectively. Furthermore, each Ir center of 5 was coordinated by two nitrogen atoms from 4-EtAp(2-), Cl- and eta(5)-cp*. Coordination of the ligand to Ni to form 3 caused an isomerization from the para-benzoquinonediimine of 4-EtApH(2) to the ortho form, with a bond alternation at each of the two N-C-C-C-N 7c-systems. Diprotonation and dinuclear complex formation to construct 1, 2, 4 and 5 led to a delocalization of six pi-electrons over each of the two N-C-C-C-N moieties connected by single bonds. The pi-pi* transition absorption gradually shifted to longer wavelengths (4-EtApH(2)approximate to 3 -> 2 -> 1 -> 4 approximate to 5), suggesting an extension of the pi-conjugation range. Cyclic voltammograms of 3 and 4 showed one and two redox potential(s), respectively. (C) 2014 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.poly.2014.07.030
  DOI ID：10.1016/j.poly.2014.07.030, ISSN：0277-5387, Web of Science ID：WOS:000343339600090
• Lattice Water-Induced Helical Stacking of Tartrate-Bridged Dinuclear Palladium(II) Complexes: The Role of Hydrogen Bonding　　　　　　　　　　　　　　　
  Keiji Ohno; Tomoaki Sugaya; Masaru Kato; Noriko Matsumoto; Ryoko Fukano; Yasuyo Ogino; Sumio Kaizaki; Takashi Fujihara; Akira Nagasawa
  CRYSTAL GROWTH & DESIGN, Volume：14, Number：8, First page：3675, Last page：3679, Aug. 2014, [Reviewed]
  Hydrous crystals of [{Pd-II(bpy)}(2)(mu-x-tart)]. nH(2)O (bpy: 2,2'-bipyridine; tartH(2)(2-): tartrate; 1a: x = L, n = 6; 2a: x = D, n = 6; 3a: x = DL, n = 4; 4a: x = meso, n = 4) and anhydrous crystals of [{Pd-II(bpy)}(2)(mu-L-tart)] (1b) were isolated from aqueous and MeOH solutions, respectively. X-ray crystallography revealed the stacked structures of clamshell-like dinuclear units in 1a-3a and 1b, where intramolecular metal metal and pi-pi stacking interactions were observed. Right- and left-handed helically stacked columns were formed in the 1a and 2a crystals, respectively. The significant role of hydrogen bonding among lattice water molecules and tartrate is suggested because 1b exhibited a zigzag arrangement only through intermolecular metal-metal interactions. In 3a, L- and D-tart units stacked alternately in a zigzag arrangement with intermolecular pi-pi interactions. In 4a, dimeric aggregates of the twisted dinuclear units further formed a 2D sheet architecture.
  AMER CHEMICAL SOC, English, Scientific journal
  DOI：https://doi.org/10.1021/cg500143w
  DOI ID：10.1021/cg500143w, ISSN：1528-7483, eISSN：1528-7505, ORCID：16525295, Web of Science ID：WOS:000340080400001
• An orthorhombic polymorph ofN¹,N⁴-diphenyl-3,6-bis(phenylimino)cyclohexa-1,4-diene-1,4-diamine
  Keiji Ohno; Takashi Fujihara; Akira Nagasawa
  Acta Crystallographica Section E Structure Reports Online, Volume：70, Number：4, First page：o495, Last page：o496, Mar. 2014
  A new orthorhombic polymorph of the title compound, C₃₀H₂₄N₄, with a density of 1.315 Mg m⁻³, has been obtained. The molecule is centrosymmetric with the centroid of the cyclohexa-1,4-diene ring located on an inversion center. The two unique benzene rings are almost perpendicular to each other [dihedral angle = 86.70 (6)°] and are oriented at dihedral angles of 30.79 (5) and 68.07 (5)° with respect to the central cyclohexadiene ring. In the crystal, π–π stacking is observed between the central cyclohexa-1,4-diene-1,4-diamine unit and a phenyl ring of a neighboring molecule [centroid–centroid distance = 3.7043 (7) Å]. The crystal structure of the triclinic polymorph [Ohnoet al.(2014).Acta Cryst.E70, o303–o304] showed chains running along theb-axis direction through weak C—H...π interactions.
  International Union of Crystallography (IUCr), Scientific journal
  DOI：https://doi.org/10.1107/s1600536814006254
  DOI ID：10.1107/s1600536814006254, eISSN：1600-5368
• N 1,N 4-Diphenyl-3,6-bis(phenylimino)cyclohexa-1,4- diene-1,4-diamine　　　　　　　　　　　　　　　
  Keiji Ohno; Haruki Maruyama; Takashi Fujihara; Akira Nagasawa
  Acta Crystallographica Section E: Structure Reports Online, Volume：70, Number：3, First page：o303, Last page：o304, Mar. 2014, [Reviewed]
  In the title compound, C30H24N4, the central benzoquinonediimine moiety is approximately planar, with a maximum deviation of 0.044 (14) Å. The four terminal phenyl rings are twisted by 44.95 (11), 54.90 (10), 44.98 (10) and 50.68 (11)° with respect to the mean plane the benzoquinonediimine unit. In the crystal, molecules are linked by weak C - H⋯π interactions into supramolecular chains running along the b-axis direction.
  English, Scientific journal
  DOI：https://doi.org/10.1107/S1600536814002906
  DOI ID：10.1107/S1600536814002906, ISSN：1600-5368, SCOPUS ID：84897744694
• Preferential Behavior on Donating Atoms of an Ambidentate Ligand 2-Methylisothiazol-3(2H)-one in Its Metal Complexes　　　　　　　　　　　　　　　
  Masaru Kato; Kei Unoura; Toshiyuki Takayanagi; Yasuhisa Ikeda; Takashi Fujihara; Akira Nagasawa
  INORGANIC CHEMISTRY, Volume：52, Number：23, First page：13375, Last page：13383, Dec. 2013, [Reviewed]
  Five metal complexes of 2-methylisothiazol-3(2H)-one (MIO), [Co-III(NH3)(5)(MIO)](3+), [Ru-II(NH3)(5)(MIO)](2+), [Ru-III(NH3)(5)(MIO)](3+), (-), and trans-, were synthesized, and their structures were determined by single-crystal X-ray crystallography. MIO is an ambidentate ligand and coordinates to metal centers through its oxygen atom in the cobalt(III), ruthenium(III), and uranium(VI) complexes and through its sulfur atom in the ruthenium(II) and platinum(III) complexes. This result suggests that MIO shows preferential behavior on its donating atoms. We also studied the electron-donor abilities of the oxygen and sulfur atoms of MIO. Various physical measurements on the conjugate acid of MIO and the MIO complexes allowed us to determine an acid dissociation constant (pK(a)) and donor number (DN) for the oxygen atom of MIO and Lever's electrochemical parameter (E-L) and a relative covalency parameter (k(L)) for the sulfur atom.
  AMER CHEMICAL SOC, English, Scientific journal
  DOI：https://doi.org/10.1021/ic401673z
  DOI ID：10.1021/ic401673z, ISSN：0020-1669, eISSN：1520-510X, ORCID：12234327, Web of Science ID：WOS:000327831600015
• Dinuclear niobium(III) and tantalum(III) complexes with thioether and selenoether ligands [{(MX2)-X-III(L)}(2)(mu-X)(2)(mu-L)] (M = Nb, Ta; X = Cl, Br; L = R2S, R2Se): Syntheses, structures, and the optimal conditions and the mechanism of the catalysis for regioselective cyclotrimerization of alkynes　　　　　　　　　　　　　　　
  Masatoshi Matsuura; Takashi Fujihara; Masaki Kakeya; Tomoaki Sugaya; Akira Nagasawa
  JOURNAL OF ORGANOMETALLIC CHEMISTRY, Volume：745, First page：288, Last page：298, Nov. 2013, [Reviewed]
  A series of dinuclear niobium(III) and tantalum(III) halide complexes with chalcogen donors [{(MX2)-X-III(L)}(2)(mu-X)(2)(mu-L)] (M = Nb; X = Cl, Br; L = R2S, R2Se) (M = Ta; X = Cl, Br; L = R2S) have been prepared by the reaction of dimetal(V) decahalide (M2X10) with magnesium and L. The structures of five of those new complexes were determined by X-ray crystallography to have a M-M double bond. It is evidenced that the solvent and the temperature play important roles in achieving high yield and regioselectivity for cyclotrimerization of alkynes. The reaction of the niobium(III) chloride complexes (L = dimethyl sulfide (Me2S), tetrahydrothiophene (C4H8S, THT, thiolane)) with phenylacetylene at room temperature in toluene gave both head-to-tail cycloadded trimers of alkyne, 1,3,5-(Ph)(3)-2,4,6-(H)(3)-benzene and head-to-head cycloadded 1,2,4-(Ph)(3)-3,5,6-(H)(3)-benzene, in high yields. The smaller the thioether ligands, the higher the catalytic activity. The niobium(III) chloride complexes with selenoether (L dimethyl selenide (Me2Se), tetrahydroselenophene (C4H8Se, THSe, selenolane) have higher rates for the reaction with alkynes, but low activity for the cyclotrimerization. Tantalum(III) chloride complexes (L = Me2S, THT, tetrahydrothiopyran (C5H10S, THTP, thiane)) have lower catalytic activities than the niobium(III) ones, because the Ta-S(mu-L) bond lengths are shorter than those of niobium analogs. The stability of the precursor complexes toward the first oxidative addition depends on the M-S(mu-L) bond strength, and controls the concentration of catalytic active species. The niobium(III) bromide complexes (L = Me2S, THT) and the tantalum(III) bromide one (L = Me2S) react with alkynes to give head-to-tail compounds regioselectively, but are less catalytically active than those of chloride complexes. (C) 2013 Elsevier B. V. All rights reserved.
  ELSEVIER SCIENCE SA, English, Scientific journal
  DOI：https://doi.org/10.1016/j.jorganchem.2013.07.035
  DOI ID：10.1016/j.jorganchem.2013.07.035, ISSN：0022-328X, eISSN：1872-8561, Web of Science ID：WOS:000326112700041
• A Kinetic Study on the Substitution for Acetonitrile at the trans-to-Oxido Sites in a Bis(mu-acetato)(mu-oxido)diruthenium(III) Dipositive Complex: Dissociative-Associative Transition of the Activation Mode for the Substitution of Pyridine Derivatives　　　　　　　　　　　　　　　
  Yohei Ido; Kiyoshi Sakaguchi; Minako Tasei; Suguru Minami; Hiroki Sawamoto; Takashi Fujihara; Akira Nagasawa
  EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Volume：2013, Number：21, First page：3641, Last page：3650, Jul. 2013, [Reviewed]
  <title content-type="main">Abstract
  A new diruthenium(III) complex [Ru-2(III)(-O)(-CH3CO2)(2)(bpy)(2)(CH3CN)(2)](PF6)(2) [1(PF6)(2), bpy = 2,2-bipyridine] has been synthesized, and the dynamic behaviour of CH3CN at the trans-to--oxido sites were investigated by H-1 NMR and UV/Vis spectroscopy at 0-60 degrees C under 0.101-147 MPa in CH3CN. The solvent exchange in CD3CN at 5 degrees C gave the rate constant k = 2.43x10(-3) s(-1) and the activation parameters H-double dagger = 124 kJmol(-1) and S-double dagger = +150 JK(-1)mol(-1), which point to a dissociative mechanism (I-d or D). The ligand substitution of pyridine (py) in CD3CN at 30 degrees C, yielding [Ru-2(III)(-O)(-CH3CO2)(2)(bpy)(2)(py)(2)](PF6)(2) [2a(PF6)(2)], gave a rate constant per site of k = 1.56x10(-2) M(-1)s(-1), and the activation parameters H-double dagger = 81 kJmol(-1) and S-double dagger = -13 JK(-1)mol(-1). The substitution of various pyridine derivatives (Rpy) for CH3CN in 1(PF6)(2) exhibited varying activation parameters: H-double dagger ranged from 66 to 92 kJmol(-1), S-double dagger ranged from -51 to +22 JK(-1)mol(-1), and V-double dagger (for Rpy with R = H, 3-Ac, 4-NH2, 4-CN, 3-CN) ranged from +1.3 to +3.2 cm(3)mol(-1). These results suggest an interchange (I) mechanism for the substitution of Rpy, for which its strong electron-donating ability is responsible. A compensation effect is seen between H-double dagger and S-double dagger, and both have linear relationships with the Hammett parameters. The substituent R electronically influences the strength of the interaction of Rpy with Ru center in the transition state to shift the activation mode to a dissociative (I-d) or an associative (I-a) interchange.
  WILEY-V C H VERLAG GMBH, English, Scientific journal
  DOI：https://doi.org/10.1002/ejic.201300173
  DOI ID：10.1002/ejic.201300173, ISSN：1434-1948, Web of Science ID：WOS:000321632100014
• Syntheses and Properties of Dinuclear Group 6 Metal Complexes with the Zwitterionic Sulfur Donor Ligand Bis(N,N-diethylamino)carbeniumdithiocarboxylate　　　　　　　　　　　　　　　
  Tomoaki Sugaya; Takeshi Ohba; Fumiya Sai; Shigeru Mashima; Takashi Fujihara; Kei Unoura; Akira Nagasawa
  ORGANOMETALLICS, Volume：32, Number：12, First page：3441, Last page：3450, Jun. 2013, [Reviewed]
  A class of dinuclear group 6 metal complexes [{M-0(CO)(5)}(2)(mu-S,S'-EtL)] (M = Cr, Mo, W) with the asymmetrically bridged zwitterionic sulfur donor bis(N,N-diethylamino)carbeniumdithiocarboxylate (EtL) was prepared by photoreaction of [M-0(CO)(6)] with EtL in hexane-CH2Cl2 for Cr and Mo or THF for W. The same structure in a syn-anti coordination mode was revealed by X-ray analyses for chromium(0) and tungsten(0) complexes, 1 and 3, respectively, and speculated from various analytical data for the molybdenum(0) complex 2. The pertinent criteria for the coordination mode are found to be the wavenumber of the asymmetric stretching vibration of the -CS2 moiety in the solid state and the ligand-based reduction potential in solution. Complexes 1 and 3 showed quasi-reversible reduction waves, which are assigned to a two-step, one-electron reduction process derived from the bridging EtL. In a series of [Cr(CO)(5)L] complexes (L = monodentate ligand), the C-13 NMR chemical shifts of the trans-to-L carbonyl group showed the order of increasing sigma-donor/pi-acceptor ratio of the ligands. The sulfur donor ligands, including EtL and thione, are positioned in the middle of this range. All complexes exhibited negative solvatochromism: the wavelength of the absorption maximum shifted to the blue side in the range 500-600 nm with an increase in the Reichardt solvent polarity parameters E-T(30), except for protic solvents. Quantum chemical calculations by time-dependent density functional theorypolarized continuum model were employed for understanding the excited states and solvatochromic properties of complex 3. The calculated vertical excitation energies in solution are consistent with the experimental data, suggesting that the transition is a metal-to-ligand charge-transfer transition. In addition, UV-vis, NMR, and cyclic voltammetry data showed that complex 3 dissociates into two mononuclear species in polar solvents: [W(CO)(5)(EtL)] and [W(CO)(5)(solvent)].
  AMER CHEMICAL SOC, English, Scientific journal
  DOI：https://doi.org/10.1021/om300831y
  DOI ID：10.1021/om300831y, ISSN：0276-7333, Web of Science ID：WOS:000321074500003
• Cis-Dichloridobis(ethyl methyl sulfide-κS)oxidovanadium(IV)　　　　　　　　　　　　　　　
  Masatoshi Matsuura; Takashi Fujihara; Akira Nagasawa
  Acta Crystallographica Section E: Structure Reports Online, Volume：69, Number：4, First page：m209, Apr. 2013, [Reviewed]
  The mononuclear title complex, [VCl2O(C3H 8S)2], features a VIV=O double bond [1.5845 (15) Å] in an overall trigonal-bipyramidal coordination environment defined by two Cl- and the S atoms of two (CH3CH 2)(CH3)S ligands. In the crystal, pairs of molecules form centrosymmetric dimers via C-H⋯O hydrogen bonds between the methyl C-H group and the oxidovanadium O atom of a neighbouring molecule.
  English, Scientific journal
  DOI：https://doi.org/10.1107/S1600536813006703
  DOI ID：10.1107/S1600536813006703, ISSN：1600-5368, SCOPUS ID：84875979626
• Di-μ-acetato-κ4 O:O′-μ-oxido- κ2 O:O′-bis[cis-(2,2′-bipyridine- κ2 N,N′)-trans-(pyridine-κN)ruthenium(III)] bis(hexafluoridophosphate)　　　　　　　　　　　　　　　
  Yohei Ido; Takashi Fujihara; Akira Nagasawa
  Acta Crystallographica Section E: Structure Reports Online, Volume：69, Number：3, First page：m145, Last page：m146, Mar. 2013, [Reviewed]
  The hemerythrin-type dinuclear title complex, [Ru2(CH3COO)2O(C10H8N2) 2(C5H5N)2](PF6)2, consists of two RuIII ions with a six-coordinate octahedral geometry, bridged by an oxide and two acetate ligands, with a bidentate 2,2′-bipyridine ligand and a pyridine ligand bonding at terminal positions. The Ru - Ru distance and Ru - O - Ru angle are 3.2838 (3) Å and 121.79 (7)°, respectively, and the average Ru - N(pyridine) bond length is 2.164 (8) Å. Several C - H⋯F, C - H⋯O and C - H⋯N interactions generate a three-dimensional network in the crystal structure. π-π stacking interactions [centroid-centroid distance = 3.6389 (3) Å] between inversion-related 2,2′-bipyridine rings are also observed. © 2013 Ido et al.
  English, Scientific journal
  DOI：https://doi.org/10.1107/S1600536813003334
  DOI ID：10.1107/S1600536813003334, ISSN：1600-5368, SCOPUS ID：84874861855
• 2-{[2,2-Bis(diethylamino)ethan-2-yliumthioyl]sulfanyl}-1, 1-bis-(diethylamino)-ethylium bis(perchlorate)　　　　　　　　　　　　　　　
  Keiji Ohno; Tomoaki Sugaya; Takashi Fujihara; Akira Nagasawa
  Acta Crystallographica Section E, Volume：68, Number：9, First page：o2753, Last page：o2754, Aug. 2012, [Reviewed]
  International Union of Crystallography, English, Scientific journal
• Electronic structure calculation study of metal complexes with a phytosiderophore mugineic acid　　　　　　　　　　　　　　　
  Masaru Kato; Shinjiro Izuka; Takashi Fujihara; Akira Nagasawa; Sigenao Kawai; Tomokazu Tanaka; Toshiyuki Takayanagi
  INORGANICA CHIMICA ACTA, Volume：370, Number：1, First page：304, Last page：310, May 2011, [Reviewed]
  Structural and thermodynamic properties of biologically important metal-mugineic acid complexes have been studied from the theoretical side in order to understand the metal-chelating mechanism of phytosiderophore mugineic acid at an atomic level. Density-functional theory methods combined with the polarizable continuum model (PCM) have been employed to obtain free energies of complex formation and redox potentials for metal-mugineic acid complexes in solution. It has been found that the free energies of complex formation calculated at the B3LYP/PCM level of theory are in moderate agreement with available experimental results. The inclusion of explicit water molecules interacting with the carboxylic groups in deprotonated mugineic acid through strong hydrogen-bonds is found to further improve the calculated free energies of complex formation. (C) 2011 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE SA, English, Scientific journal
  DOI：https://doi.org/10.1016/j.ica.2011.01.091
  DOI ID：10.1016/j.ica.2011.01.091, ISSN：0020-1693, ORCID：12234332, Web of Science ID：WOS:000289556300045
• Ferromagnetic Spin Ladder System: Stack of Chlorido-Bridged Dinuclear Copper(II) Complexes with 2-Methylisothiazol-3(2H)-one　　　　　　　　　　　　　　　
  Masaru Kato; Kazuo Hida; Takashi Fujihara; Akira Nagasawa
  EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Number：4, First page：495, Last page：502, Feb. 2011, [Reviewed]
  A dinuclear copper(II) complex, [{Cu(II)Cl(O-mi)}(2)(mu-Cl)(2)] [mi = 2-methylisothiazol-3(2H)-one], has been synthesized and its molecular structure in the solid state determined by single-crystal X-ray analysis. The crystal consists of centrosymmetric dinuclear copper(II) units in which each copper(II) ion is doubly bridged by two chloride ions and has a slightly distorted square-planar geometry with a terminal chlorido ligand and a terminal mi ligand coordinated through the oxygen atom. The dinuclear units stack one on top of another to form a one-dimensional two-leg ladder structure. The magnetic susceptibility of the powder was measured in the temperature range 3.0-302 K. It was found that there are ferromagnetic interactions along the rung (in the same direction of the intramolecule; J(rung) = +5.03 +/- 0.03 cm(-1)) and the leg (in the same direction of the intermolecule; J(leg) = +1.96 +/- 0.02 cm(-1)) and an antiferromagnetic interaction along the diagonal (J(x) = -1.36 +/- 0.02 cm(-1)), the experimental data being fitted by the numerical calculation for a twelve-site ladder Hamiltonian. In addition, DFT calculations with the UB3LYP functional on the model complex [{Cu(II)Cl(O-mi)}(2)(mu-Cl)(2)] gave an intramolecular magnetic coupling constant J = +28.6 cm(-1) and indicated that the spin-density distribution on O in mi is less than that on the terminal Cl. We conclude that the O-donor ligand at the terminal position plays an essential role in the emerging intramolecular ferromagnetic interaction.
  WILEY-V C H VERLAG GMBH, English, Scientific journal
  DOI：https://doi.org/10.1002/ejic.201000096
  DOI ID：10.1002/ejic.201000096, ISSN：1434-1948, ORCID：12234333, Web of Science ID：WOS:000287160500006
• Resorcin[4]arene cavitand with 1,3,2-benzodiazaborolyl walls as a fluorescence receptor for ammonium cations　　　　　　　　　　　　　　　
  Yuji Kubo; Kazusa Tsuruzoe; Sachiko Okuyama; Ryuhei Nishiyabu; Takashi Fujihara
  CHEMICAL COMMUNICATIONS, Volume：46, Number：20, First page：3604, Last page：3606, 2010
  Resorcin[4]arene cavitand 1 with 1,3,2-benzodiazaborolyl walls was newly synthesized. It showed a large blue shift in the fluorescence spectra upon selective complexation with alkyltrimethylammonium salts in CH2Cl2-DMSO (9:1 v/v); this shift was detectable with the naked eye.
  ROYAL SOC CHEMISTRY, English, Scientific journal
  DOI：https://doi.org/10.1039/c0cc00259c
  DOI ID：10.1039/c0cc00259c, ISSN：1359-7345, eISSN：1364-548X, PubMed ID：20383396, SCOPUS ID：77952391505, Web of Science ID：WOS:000277487700053
• Group 12 metal complexes with inner-salt, bis(N,N-disubstituted amino)carbeniumdithiocarboxylate. Asymmetric stretching vibration of thiocarboxylate and reduction potential as probes for the coordination mode　　　　　　　　　　　　　　　
  Tomoaki Sugaya; Takashi Fujihara; Akira Nagasawa; Kei Unoura
  Inorganica Chimica Acta, Volume：362, Number：13, First page：4813, Last page：4822, Jul. 2009, [Reviewed]
  Elsevier B.V., English, Scientific journal
• Linkage isomerism of pentaammine(dimethylsulfoxide)ruthenium(II/III) complexes: A theoretical study
  Kato Masaru; Takayanagi Toshiyuki; Fujihara Takashi; Nagasawa Akir
  Inorganica Chimica Acta, Volume：362, Number：4, First page：1199, Last page：1203, 2009, [Reviewed]
  DOI：https://doi.org/10.1016/j.ica.2008.06.012
  DOI ID：10.1016/j.ica.2008.06.012, ORCID：12234336
• Rearrangement of the tert-butyl group of 5,6-di-tert-butyl-2,3,7-trithiabicylo-5-ene 7-endoxide　　　　　　　　　　　　　　　
  Sanae Yoshida; Yuta Morohashi; Takashi Fujihara; Yoshiaki Sugihara; Juzo Nakayama
  JOURNAL OF SULFUR CHEMISTRY, Volume：29, Number：1, First page：1, Last page：7, 2008, [Reviewed]
  Treatment of 5,6-di-tert-butyl-2,3,7-trithiabicylo-5-ene 7-endoxide with trimethylsilyl trifluoromethanesulfonate at room temperature resulted in the rearrangement of tert-butyl group to furnish 4,6-di-tert-butyl- 2,3,7-trithiabicylo-5-ene 7-endoxide quantitatively. Meanwhile, treatment of the compound by trimethyloxonium tetrafluoroborate afforded 4,5-di-tert-butyl-1,2-dithiin 1,1-dioxide in addition to the above rearrangement product.
  TAYLOR & FRANCIS LTD, English, Scientific journal
  DOI：https://doi.org/10.1080/17415990701753373
  DOI ID：10.1080/17415990701753373, ISSN：1741-5993, Web of Science ID：WOS:000269194500001
• 1,1,1-tris(phenylsulfonyloxymethyl)ethane　　　　　　　　　　　　　　　
  Takashi Fujihara; Eri Shioji; Akira Nagasawa
  ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, Volume：63, First page：O3628, Last page：U4627, Aug. 2007, [Reviewed]
  In the crystal structure of the title compound, C23H24O9S3, intermolecular C-H center dot center dot center dot O hydrogen bonds are found, which link the molecules into a three-dimensional network. Weak C-H center dot center dot center dot pi interactions are also present in the structure.
  BLACKWELL PUBLISHING, English, Scientific journal
  DOI：https://doi.org/10.1107/S1600536807035507
  DOI ID：10.1107/S1600536807035507, ISSN：1600-5368, Web of Science ID：WOS:000249692200421
• Mutual influences of ligands as revealed by H-2 NMR shifts and the angular overlap model parameters: trans- and cis-[CrX2(N)(4)]-type complexes with aliphatic amine ligands　　　　　　　　　　　　　　　
  Yukiko Yamaguchi-Terasaki; Takashi Fujihara; Sumio Kaizaki
  EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Number：21, First page：3394, Last page：3399, Jul. 2007, [Reviewed]
  We have previously reported the relationship between H-2 NMR chemical shift differences (Delta delta) and the angular overlap model (AOM) parameter e(sigma)(F), which represents the sigma antibonding interaction energy obtained from the solvatochromism, for trans-[CrF2([D-4]-3,2,3-tet)](n+) {[D-4]3,2,3-tet = 1,10-diamino-4,7-diazadecane [NH2(CH2)(3)NH(CD2)(2)NH(CH2)(3)NH2]} and cis-alpha-[CrF2([D-4]trien)](n+) {[D-4]trien = triethylene-tetraamine [NH2(CH2)(2)NH(CD2)(2)NH(CH2)(2)NH2]}. In analogy to these relations, the co-ligand effect on the Delta delta values for cis-alpha-[CrX2([D-4]trien)](n+) and trans-[CrX2([D-4]3,2,3-tet)](n+) is found to be well correlated with the reported e(sigma)(X) values for the co-ligands X. This is the first example of the co-ligand effect, or a mutual influence of ligands, associated with variation of the Cr-N and Cr-X bonds in cis- and trans-[CrX2N4]-type complexes. This Delta delta vs. e,(X) correlation offers an indirect method for estimating the e(sigma)(X) values for didentate X-2 as well as monodentate X ligands from the H-2 NMR chemical shifts and ranking them in the two-dimensional spectrochemical series. Plots of Delta delta vs. e(sigma)(FX) for trans-[CrF(X)([D-4]3,2,3-tet)](n+) do not necessarily lie on the Delta delta vs. e(sigma)(X) correlation line for the F(X) complexes with averaged e(sigma)(FX) = 1/2[e(sigma)(X) + e(sigma)(F)] values - e(sigma)[F(CN)] is close to e(sigma)(F), for example - thereby demonstrating a mutual influence between the CN- and F- ligands in the trans positions through a pushpull action or pi donor-acceptor interaction. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007).
  WILEY-V C H VERLAG GMBH, English, Scientific journal
  DOI：https://doi.org/10.1002/ejic.200601092
  DOI ID：10.1002/ejic.200601092, ISSN：1434-1948, Web of Science ID：WOS:000248558600013
• Mutual influences of ligands as revealed by the H-2 NMR chemical shifts and the angular overlap model parameters: cis-[CrX2(N)(4)] and fac-[CrX3(N)(3)]-type complexes with aromatic amines　　　　　　　　　　　　　　　
  Yukiko Terasaki; Takashi Fujihara; Sumio Kaizaki
  EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Number：21, First page：3400, Last page：3404, Jul. 2007, [Reviewed]
  A mutual influence of ligands through a pi donor-acceptor interaction is found by examining how the X co-ligands of the aromatic amine complexes cis-[CrX2([D-4]bpy)(2)](n+) (bpy = 2,2'-bipyridine) and fac-[CrX3([D-12]tpa)](n+) [tpa = tris(2-pyridyl)amine] affect the H-2 NMR chemical shifts in connection with the Angular Overlap Model (AOM) parameterization in an analogous manner to our previous study on the solvato-chromism and solvent-dependent H-2 NMR spectra of cis-[CrF2([D-4]bPy)(2)](+) and fac-[CrF3([D-12]tpa)]. The ranking of the AOM parameter for monodentate and/or didentate ligands can be obtained from this co-ligand effect only from the H-2 NMR shifts. The postulated relative order in the two-dimensional spectrochemical series is Cl- > Br- > O or N donors (mal(2-) > acac(-) or H2O > dmf > NCS-) for the aromatic amine complexes, which contrasts with the order O or N donors > Cl- > Br- for the aliphatic amine complexes(see the preceding paper in this issue). This fact suggests that the Cr-Cl and Cr-Br sigma bonds are stronger in the soft acidic aromatic amine complexes than those in the hard acidic aliphatic amine complexes. This means they have a higher affinity for soft basic Cl- and Br- ligands and can be explained in terms of the hard/soft acid/base (HSAB) concept. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007).
  WILEY-V C H VERLAG GMBH, English, Scientific journal
  DOI：https://doi.org/10.1002/ejic.200601093
  DOI ID：10.1002/ejic.200601093, ISSN：1434-1948, Web of Science ID：WOS:000248558600014
• 3-hydroxy-2-methylisothiazolium chloride monohydrate: an intermolecular three-dimensional network via O-H center dot center dot center dot O and O-H center dot center dot center dot Cl hydrogen bonds　　　　　　　　　　　　　　　
  Masaru Kato; Takashi Fujihara; Daisaku Yano; Akira Nagasawa
  ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, Volume：63, First page：O1839, Last page：O1841, Apr. 2007, [Reviewed]
  The title compound, C4H6ClNOS center dot H2O, has a planar five-membered ring, with a delocalized positive charge. A three-dimensional network is formed through intermolecular O-H center dot center dot center dot O and O-H center dot center dot center dot Cl hydrogen bonds between 3-hydroxy-2-methylisothiazolium cations and water molecules, and between water molecules and chloride anions.
  BLACKWELL PUBLISHING, English, Scientific journal
  DOI：https://doi.org/10.1107/S1600536807011129
  DOI ID：10.1107/S1600536807011129, ISSN：1600-5368, ORCID：12234339, Web of Science ID：WOS:000245436300244
• On the accuracy of density-functional methods for determining structures of dicationic binuclear ruthenocene derivatives bridged by an unsaturated molecule　　　　　　　　　　　　　　　
  Toshiyuki Takayanagi; Kenta Takahashi; Takashi Fujihara; Masaru Sato
  JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM, Volume：806, Number：1-3, First page：85, Last page：92, Mar. 2007, [Reviewed]
  Various exchange and correlation functionals have been examined in density-functional calculations for obtaining reliable optimized structures for dicationic binuclear ruthenocenes bridged by an unsaturated compound, which has a characteristic fulvene-type structure. First, we have performed extensive calculations for ruthenocene (RuCp2) in D-5h symmetry. It has been found that the Ru-Cp optimized distance is linearly correlated with the energy difference between highest occupied a(1)' and e(2)' orbitals. We have then found that the optimized structure of dicationic binuclear ruthenocenes is strongly dependent of the a(1)'-e(2)' orbital sequence observed in RuCp2. In particular, when exchange-correlation functionals giving the a(1)' < e(2)' orbital sequence are employed, the contribution of the fulvene-type structure is found to be significantly underestimated in the optimized structure of dicationic binuclear ruthenocenes. We finally demonstrate that the SVWN exchange-correlation functionals give reasonable optimized structures comparable to experimental structures determined by X-ray crystallography analysis. (c) 2006 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/j.theochem.2006.11.011
  DOI ID：10.1016/j.theochem.2006.11.011, ISSN：0166-1280, Web of Science ID：WOS:000244829700009
• cis-Bis(2,2 '-bipyridine)difluorochromium(III) perchlorate　　　　　　　　　　　　　　　
  Yukiko Yamaguchi-Terasaki; Takashi Fujihara; Akira Nagasawa; Sumio Kaizaki
  ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, Volume：63, First page：M593, Last page：M595, Feb. 2007, [Reviewed]
  In the title compound, cis-[CrF2(C10H8N2)(2)]ClO4, the Cr-III ion is coordinated by the four N atoms [Cr-N = 2.0480 ( 14)2.0842 ( 14) angstrom] from two 2,2'-bipyridine ligands and two F- ions [Cr-F = 1.8409 ( 10) and 1.8541 ( 10) A] in a distorted octahedral arrangement. The crystal packing is stabilized by pi-pi interactions and weak intermolecular C - H center dot center dot center dot F and C-H H center dot center dot center dot O hydrogen bonds.
  BLACKWELL PUBLISHING, English, Scientific journal
  DOI：https://doi.org/10.1107/S1600536807003157
  DOI ID：10.1107/S1600536807003157, ISSN：1600-5368, Web of Science ID：WOS:000245187300135
• 5-Chloro-2-methylisothiazolin-3-one: intermolecular two-dimensional networks via unusual C-Cl...O=C interactions
  Kato Masaru; Fujihara Takashi; Yano Daisaku; Nagasawa Akir
  Acta Crystallographica Section E-Structure Reports Online, Volume：63, First page：O3097, Last page：U2523, 2007, [Reviewed]
  DOI：https://doi.org/10.1107/S1600536807026025
  DOI ID：10.1107/S1600536807026025, ORCID：12234340
• Synthesis and some properties of bis(ruthenocenyl)thiophene derivatives - Possible spin-coupling in the two-electron oxidized species of dinuclear ruthenocenes bridged by thiophene derivatives　　　　　　　　　　　　　　　
  Masaru Sato; Yusuke Kubota; Atsushi Tanemura; Genta Maruyama; Takashi Fujihara; Juzo Nakayama; Toshiyuki Takayanagi; Kenta Takahashi; Kei Unoura
  EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Number：22, First page：4577, Last page：4588, Nov. 2006, [Reviewed]
  WILEY-V C H VERLAG GMBH, English, Scientific journal
  DOI：https://doi.org/10.1002/ejic.200600370
  DOI ID：10.1002/ejic.200600370, ISSN：1434-1948, Web of Science ID：WOS:000242551900015
• Dinuclear niobium(III) complexes [{NbCl2(L)}(2)(mu-Cl)(2)(mu-L)] (L = tetrahydrothiophene, dimethyl sulfide): Preparation, molecular structures, and the catalytic activity for the regioselective cyclotrimerization of alkynes　　　　　　　　　　　　　　　
  Masaki Kakeya; Takashi Fujihara; Takashi Kasaya; Akira Nagasawa
  ORGANOMETALLICS, Volume：25, Number：17, First page：4131, Last page：4137, Aug. 2006, [Reviewed]
  Dinuclear niobium complexes [ {NbCl2L}(2)( mu-Cl)(2)( mu-L)] ( L) tetrahydrothiophene C4H8S, THT ( 1a)) have been prepared by the reaction of diniobium( V) decachloride ( Nb2Cl10) with magnesium in THT. The structure of 1a was determined by X-ray crystallography to have a Nb-Nb bond, which is consistent with that of 1b ( L) dimethyl sulfide, Me2S). The reaction of 1a, as well as 1b, with alkyne ( R1C CR2) at room temperature gave a head-to-tail cycloadded alkyne trimer, 1,3,5-( R-1)(3)-2,4,6-( R-2)(3)-benzene ( R-1) H, R-2) Ph ( 2); R-1) p-tolyl, R-2) H ( 3); R-1) R-2) CH2Cl ( 4); R-1) R-2) COOEt ( 5); R-1) n-Pr, R-2) Me ( 6); R-1) n-Bu, R-2) H ( 7); R-1) Me3Si, R-2) H ( 8), R-1) R-2) Et ( 9), R-1) R-2) n-Pr ( 10)), regioselectively in high yields. The cyclotrimerization is found to be catalyzed by complexes 1a and 1b, since only 1/600 equiv of the complex to the alkynes can lead to the corresponding product in high yields. The reactions of 1a with 6 equiv of 3-hexyne and 4-octyne gave a mononuclear byproduct, NbCl3( eta(2)-RC CR-RC=CR) ( R) Et ( 11), Pr ( 12)), besides 9 and 10, respectively. The reactions of 11 or 12 with an excess of original alkyne, however, resulted exclusively in the formation of the corresponding benzene derivative, in equimolar amount to 1,2,3,4-( R) 4- 5,6-( R')(2)-benzene ( R) R') Et ( 9), R) R') Pr ( 10), R) Et, R') Pr ( 13), R) n-Pr, R') Et ( 14)). This observation suggests that the mononuclear species does not behave as a catalyst, and the regioselectivity may be due to a dinuclear structure of the niobium complexes.
  AMER CHEMICAL SOC, English, Scientific journal
  DOI：https://doi.org/10.1021/om0601100
  DOI ID：10.1021/om0601100, ISSN：0276-7333, Web of Science ID：WOS:000239536800016
• 4,4′-Dinonyl-2,2′-bipyridine　　　　　　　　　　　　　　　
  Takashi Fujihara; Hajime Suzuki; Akira Nagasawa
  Acta Crystallographica Section E: Structure Reports Online, Volume：61, Number：6, First page：o1867, Last page：o1868, Jun. 2006, [Reviewed]
  The title compound, C28H44N2, is one of the precursors of the amphiphilic heteroleptic ruthenium(II) sensitizer for DSC (dye-sensitized solar cells), and its molecule has a crystallographically imposed centre of symmetry. A segregated packing structure between the alkyl chain layers and pyridine rings is observed. © 2005 International Union of Crystallography Printed in Great Britain - all rights reserved.
  English, Scientific journal
  DOI：https://doi.org/10.1107/S1600536805015849
  DOI ID：10.1107/S1600536805015849, ISSN：1600-5368, SCOPUS ID：32244448004
• (E)-1-Mercapto-1-(p-tolylsulfanyl)-N-(p-tosylmethyl) methanimine: A two-dimensional supramolecular network of S - H⋯O and C - H⋯π interactions　　　　　　　　　　　　　　　
  Masaki Kakeya; Takashi Fujihara; Akira Nagasawa
  Acta Crystallographica Section E: Structure Reports Online, Volume：62, Number：4, First page：o1384, Last page：o1386, Apr. 2006, [Reviewed]
  In the crystal structure of the title compound, C16H 17NO2S3, the dihedral angle between the mean planes of the two benzene rings is 70.8 (1)°. There are intermolecular S - H⋯O and C - H⋯π interactions, and molecules are linked into a two-dimensional network. The layers are further linked together by weak C - H⋯O interactions. © 2006 International Union of Crystallography All rights reserved.
  English, Scientific journal
  DOI：https://doi.org/10.1107/S160053680600849X
  DOI ID：10.1107/S160053680600849X, ISSN：1600-5368, SCOPUS ID：33744921060
• Di-mu-chloro-mu-(dimethyl sulfide)-bis[dichloro(dimethyl sulfide) niobium(III)]　　　　　　　　　　　　　　　
  M Kakeya; T Fujihara; A Nagasawa
  ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, Volume：62, First page：M553, Last page：M554, Mar. 2006, [Reviewed]
  The title compound, [Nb2Cl6(C2H6S)(3)], contains an Nb-III=Nb-III double bond [2.6880 (3)angstrom]. Each Nb atom has a distorted octahedral coordination environment formed by two terminal and two bridging Cl- ions, and one monodentate and one bridging Me2S ligands.
  BLACKWELL PUBLISHING, English, Scientific journal
  DOI：https://doi.org/10.1107/S1600536806005149
  DOI ID：10.1107/S1600536806005149, ISSN：1600-5368, Web of Science ID：WOS:000235681100069
• Tetra-n-propylammonium perchlorate　　　　　　　　　　　　　　　
  Takashi Fujihara; Masaru Kato; Akira Nagasawa
  Acta Crystallographica Section E: Structure Reports Online, Volume：61, Number：5, First page：o1439, Last page：o1440, May 2005, [Reviewed]
  The crystallographic analysis of the title compound, C12H 28N+·ClO4 -, (I), shows that intermolecular C-H⋯O interactions stabilize the crystal structure. The compound is isomorphous with tetra-n-propylammonium iodide, whose structure has been described by Yoshida et al. [Acta Cryst. (1994). C50, 1758-1760]. © 2005 International Union of Crystallography Printed in Great Britain - all rights reserved.
  English, Scientific journal
  DOI：https://doi.org/10.1107/S1600536805012006
  DOI ID：10.1107/S1600536805012006, ISSN：1600-5368, SCOPUS ID：18544384488
• Di-μ-chloro-bis[diacetonitriledichloro-niobium(III)] acetonitrile disolvate　　　　　　　　　　　　　　　
  Masaki Kakeya; Takashi Fujihara; Akira Nagasawa
  Acta Crystallographica Section E: Structure Reports Online, Volume：60, Number：7, First page：m893, Last page：m894, Jul. 2004, [Reviewed]
  The title compound, [Nb2(μ-Cl)2Cl 4(CH3CN)4]·2CH3CN, is a centrosymmetric dinuclear niobium complex containing an NbIII = NbIII double bond [2.8577 (9) Å]. The Nb atom has a distorted octahedral coordination environment formed by two terminal Cl atoms [Nb-Cl = 2.3761 (14) and 2.3853 (15) Å], two acetonitrile ligands [Nb-N = 2.301 (4) and 2.309 (4) Å] and two μ-Cl atoms [Nb-Cl = 2.3356 (13) and 2.3358 (13) Å]. © 2004 International Union of Crystallography Printed in Great Britain - all rights reserved.
  English, Scientific journal
  DOI：https://doi.org/10.1107/S1600536804012760
  DOI ID：10.1107/S1600536804012760, ISSN：1600-5368, SCOPUS ID：18444402217
• N,N,N′,N′-Tetrakis(2-pyridiniomethyl)-1,3-diaminopropane tetraperchlorate monohydrate　　　　　　　　　　　　　　　
  Takashi Fujihara; Miki Saito; Akira Nagasawa
  Acta Crystallographica Section E: Structure Reports Online, Volume：60, Number：7, First page：o1126, Last page：o1128, Jul. 2004, [Reviewed]
  The cation of the title compound H4tptn4+· 4ClO4 -·H2O, where H4tptn 4+ is N,N,N′,N′-tetrakis(2-pyridiniomethyl)-1,3- diaminopropane (C27H34N6 4+), contains an intramolecular N - H⋯N hydrogen bond, and the average ring angle at the N atoms in the pyridinium rings is 123.6 (1)°. Intermolecular N - H⋯O and O - H⋯O hydrogen bonds are also found in the crystal structure. © 2004 International Union of Crystallography Printed in Great Britain - all rights reserved.
  English, Scientific journal
  DOI：https://doi.org/10.1107/S1600536804011961
  DOI ID：10.1107/S1600536804011961, ISSN：1600-5368, SCOPUS ID：18444401757
• Fac-Triaqua[tris(2-pyridyl)amine-κ3N]chromium(III) tris(trifluoromethanesulfonate)　　　　　　　　　　　　　　　
  Yukiko Terasaki; Takashi Fujihara; Akira Nagasawa; Sumio Kaizaki
  Acta Crystallographica Section E: Structure Reports Online, Volume：60, Number：6, First page：m854, Last page：m856, Jun. 2004, [Reviewed]
  In the title compound, fac-[Cr(tpa)(H2O)3](CF 3SO3)3 [tpa is tris(2-pyridyl)amine
  C 15H12N4], the CrIII ion is coordinated by the symmetry-related N atoms of tpa, which acts as a tripodal ligand, and O atoms of water
  a threefold rotation axis passes through the Cr and amine N atoms, with Cr-Npyridyl and CrO distances of 2.0403 (12) and 1.9815 (11) A, respectively. A three-dimensional network is formed by intermolecular O-H⋯O hydrogen bonds between coordinated water molecules and sulfonate groups of the anions. © 2004 International Union of Crystallography Printed in Great Britain - all rights reserved.
  English, Scientific journal
  DOI：https://doi.org/10.1107/S1600536804011912
  DOI ID：10.1107/S1600536804011912, ISSN：1600-5368, SCOPUS ID：18444388004
• Tetrakis(1,3-dimethylimidazolidinium-2-dithiocarboxylate-κS)zinc(II) diperchlorate　　　　　　　　　　　　　　　
  Takashi Fujihara; Tomoaki Sugaya; Akira Nagasawa; Juzo Nakayama
  Acta Crystallographica Section E: Structure Reports Online, Volume：60, Number：3, First page：m282, Last page：m284, Mar. 2004, [Reviewed]
  The title compound, [Zn(C6H10N2S 2)4](ClO4)2, containing four inner-salt ligands, is considered to retain an inner-salt structure in the crystal structure, where the planes of the carbenium and the dithiocarboxylate moieties are nearly perpendicular to each other [85 (2)°]. The asymmetric unit consists of one-half of the complex molecule, as the complex has twofold crystallographic symmetry. The backbone C-C bond length [N2C-CS 2 = 1.488 (7) Å] is significantly shorter than that of a normal C-C single bond. © 2004 International Union of Crystallography Printed in Great Britain - all rights reserved.
  English, Scientific journal
  DOI：https://doi.org/10.1107/S160053680400217X
  DOI ID：10.1107/S160053680400217X, ISSN：1600-5368, SCOPUS ID：18444387406
• Bis(tetraethylammonium) 2,2′-bipyridine-4,4′-dicarboxylate tetrahydrate　　　　　　　　　　　　　　　
  Takashi Fujihara; Atsuo Kobayashi; Akira Nagasawa
  Acta Crystallographica Section E: Structure Reports Online, Volume：60, Number：3, First page：o353, Last page：o355, Mar. 2004, [Reviewed]
  The title compound, 2C8H20N+·C 12H6N2O4 2-·4H 2O, which is one of the precursors of the dye for DSC (dye-sensitized solar cells), consists of tetraethylammonium cations, 2,2′-bipyridine-4, 4′-dicarboxylate anions and water molecules. The anion has a centre of symmetry and the pyridine ring is inclined to the carboxylate group by 7.9 (3)°. A two-dimensional network is formed through intermolecular O-H⋯O hydrogen bonds between water molecules and the carboxylate groups of the anions. © 2004 International Union of Crystallography Printed in Great Britain - all rights reserved.
  English, Scientific journal
  DOI：https://doi.org/10.1107/S1600536804002910
  DOI ID：10.1107/S1600536804002910, ISSN：1600-5368, SCOPUS ID：18444378422
• N,N,N′,N′-Tetrakis(2-pyridylmethyl)-1,2-diaminoethane: A multidentate ligand　　　　　　　　　　　　　　　
  Takashi Fujihara; Miki Saito; Akira Nagasawa
  Acta Crystallographica Section E: Structure Reports Online, Volume：60, Number：2, First page：o262, Last page：o263, Feb. 2004, [Reviewed]
  The reaction of 1,2-diaminoethane and 2-pyridinecarboxyaldehyde in the presence of a reducing agent, sodium triacetoxyborohydride, leads to the title compound, C26H28N6. The molecule has a centre of symmetry. © 2004 International Union of Crystallography Printed in Great Britain - all rights reserved.
  English, Scientific journal
  DOI：https://doi.org/10.1107/S1600536804001254
  DOI ID：10.1107/S1600536804001254, ISSN：1600-5368, SCOPUS ID：18444392694
• A series of [Cr2(μ-OH)n(μ-RCO2) 3-n(bispma)2] type chromium (III) dinuclear complexes (n = 1, 2) with tridentate bis (2-pyridylmethyl)amine (bispma): Synthesis, crystal structure, and magnetic properties　　　　　　　　　　　　　　　
  Takashi Fujihara; Akira Fuyuhiro; Sumio Kaizaki
  Inorganica Chimica Acta, Volume：278, Number：1, First page：15, Last page：23, Aug. 1998, [Reviewed]
  A series of chromium (III) dinuclear complexes with general formula [Cr2(μ-OH)n(μ-RCO2) 3-n(bispma)2]Xm·yH2O(bispma = bis(2-pyridylmethyl)amine
  n = 1, m = 3, R = H, Me, Et, CH2Cl, CH2ClCH2
  m = 4, R = CH2NH3, CH2CH2NH3, CH2CH2CH2NH3, CH(CH3)NH3, CH(OH)NH3
  n = 2, m = 3, R = CH3, H) was prepared and characterized by elemental analysis, UV-Vis, IR absorption and 2H NMR spectra, magnetic susceptibility measurements, and X-ray crystal structure analysis. The crystal of [Cr2(μ-OH)2(μ-HCO2)(bispma)2] [ClO4]3· 0.5H2O was orthorhombic with space group Pnma, a = 14.771 (3), b= 12.346(6), c = 19.054(4) Å, U = 3474(1) Å3, Z = 4. Two complexes for R = H and CH2Cl were found to exhibit alternating magnetic properties from antiferromagnetic to ferromagnetic interaction with change of counter ions. This anomalous magnetism was examined by comparison with the reported magneto-structural relationship. © 1993 Elsevier Science S.A. All rights reserved.
  Elsevier S.A., English, Scientific journal
  DOI：https://doi.org/10.1016/S0020-1693(97)06169-0
  DOI ID：10.1016/S0020-1693(97)06169-0, ISSN：0020-1693, SCOPUS ID：0001894294
• Preparative Study and Characterization of the Cis-Diamminetetranitrocobaltate(III) Ion. A Missing Link in the Ammine-Nitro Cobalt(III) Series.　　　　　　　　　　　　　　　
  FUJITA Miho; FUJIHARA Takashi; KOJIMA Masaaki; YOSHIKAWA Yuzo; YAMASAKI Kazuo
  Proceedings of the Japan Academy, Volume：73, Number：8, First page：161, Last page：164, 1997
  The preparative conditions and stability of cis-[Co(NO₂)₄(NH₃)₂]^-, which had been a missing link in the ammine-nitro cobalt(III) series until recently, were studied using ⁵⁹Co NMR spectroscopy. The reaction of Na₃[Co(NO₂)₆] with liquid ammonia mainly gave cis-[Co(NO₂)₄(NH₃)₂]^- together with mer- and fac-[Co(NO₂)₃(NH₃)₃] and cis-[Co(NO₂)₂(NH₃)₄]⁺; the formation of trans-[Co(NO₂)₄(NH₃)₂]^- was not observed. The reaction of aqueous [Co(NO₂)₆]^3- with aqueous ammonia also gave the cis isomer as a major product. On the contrary, the cis isomer did not form during the conventional preparation from CoCl₂ in an aqueous solution. The cis isomer was very stable in the solid state, but the isomer slowly isomerized in water (t_1/2>5 days at room temperature, ca. 0.1mol dm_-3) to the trans isomer. The reaction was accompanied by the formation of fac-[Co(NO₂)₃(NH₃)₃] which then isomerized to the mer isomer, and by the formation of several unknown species.
  The Japan Academy, English
  DOI：https://doi.org/10.2183/pjab.73.161
  DOI ID：10.2183/pjab.73.161, ISSN：0386-2208, CiNii Articles ID：130000903006, CiNii Books ID：AA00785485
• Correlation of 13C, 15N and 59Co nuclear magnetic resonance chemical shifts with ligand-field parameters for pentacyanocobaltate(III) complexes　　　　　　　　　　　　　　　
  Takashi Fujihara; Sumio Kaizaki
  Journal of the Chemical Society, Dalton Transactions, Number：8, First page：1275, Last page：1279, 1993, [Reviewed]
  The 13C, 15N and 59Co NMR spectra of 15 pentacyanocobaltate(III) complexes revealed a common tendency for the chemical shift to vary with the identity of the sixth co-ordinated ligand. These chemical shifts were found to correlate with ligand-field parameters, including the nephelauxetic ratio, among them the reduction parameter having a significant effect.
  English, Scientific journal
  DOI：https://doi.org/10.1039/DT9930001275
  DOI ID：10.1039/DT9930001275, ISSN：1472-7773, SCOPUS ID：37049082943
• Diamagnetic behaviour of high-resolution nitrogen-14 nuclear magnetic resonance spectra for co-ordinated nitrogens in paramagnetic chromium(III) diamine complexes　　　　　　　　　　　　　　　
  Takashi Fujihara; Sumio Kaizaki
  Journal of the Chemical Society, Dalton Transactions, Number：16, First page：2521, Last page：2524, 1993, [Reviewed]
  Diamagnetic behaviour in the chemical shift and linewidth of high-resolution nitrogen-14 NMR spectra for paramagnetic chromium(III) diamine complexes was investigated in comparison with that for the corresponding diamine dihydrochlorides and the diamagnetic cobalt(III) complexes. The NMR signals can be assigned to each inequivalent nitrogen ligating atom of unsymmetic diamines in the chromium(III) complexes. The 14N NMR spectra are affected by the diamine chelate ring conformations of the tris(diamine) complexes, but hardly sensitive to the ligand replacement in trans- and cis-[CrX2(diamine)2] type complexes.
  English, Scientific journal
  DOI：https://doi.org/10.1039/DT9930002521
  DOI ID：10.1039/DT9930002521, ISSN：1472-7773, SCOPUS ID：0008325301

• Magnetic properties of layered copper and cobalt cinnamate complexes　　　　　　　　　　　　　　　
  市村奏絵; 藤原隆司; 木田孝則; 萩原政幸; 鎌田憲彦; 本多善太郎
  日本磁気学会学術講演概要集, Volume：44th, 2020
  ISSN：1882-2959, J-Global ID：202102250230299548
• 一次元金属錯体M(sba)(H₂O)₂・H₂O(M=Co,Cu)の磁気異方性　　　　　　　　　　　　　　　
  野本尚之; 藤原隆司; 澤田祐也; 木田孝則; 萩原政幸; 鎌田憲彦; 本多善太郎
  Volume：43rd, 2019
  ISSN：1882-2959, J-Global ID：202002284951988664
• H₂Oを架橋配位子とする1次元構造金属錯体の磁性
  野本尚之; 藤原隆司; 澤田祐也; 木田孝則; 萩原政幸; 鎌田憲彦; 本多善太郎
  日本磁気学会学術講演概要集, Volume：42nd, First page：124, 28 Aug. 2018
  Japanese
  ISSN：1882-2959, J-Global ID：201802236748914308
• Synthesis and phase structures of novel pi-acceptor discotic liquid crystalline compounds having a pyrenedione core　　　　　　　　　　　　　　　
  Mikio Yasutake; Takashi Fujihara; Akira Nagasawa; Keiichi Moriya; Takuji Hirose
  EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Volume：2008, Number：24, First page：4120, Last page：4125, Aug. 2008
  Several pi-acceptor discotic liquid crystalline compounds were synthesized by using a pyrenedione unit as a core. Terrace-like and band-like structures were revealed by polarized optical microscopy (POM) observations and XRD measurements. In conjunction with the results of the single-crystal structure analysis of analogous crystalline compounds, all of the liquid crystalline compounds were confirmed to form a discotic lamellar phase D(L2). ((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008).
  WILEY-BLACKWELL, English
  DOI：https://doi.org/10.1002/ejoc.200800360
  DOI ID：10.1002/ejoc.200800360, ISSN：1434-193X, CiNii Articles ID：80019737426, Web of Science ID：WOS:000258808000006
• (-)(545)-fac-Delta-Tris(L-prolinato)cobalt(III) trihydrate　　　　　　　　　　　　　　　
  Masaru Kato; Miho Hayashi; Takashi Fujihara; Akira Nagasawa
  ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, Volume：64, First page：M684, Last page：U621, May 2008
  The absolute configuration of the octahedral fac-CoN3O3 title complex, [Co(C5H8NO2)(3)]center dot 3H(2)O, has been determined by single-crystal X- ray analysis. A three-dimensional network of hydrogen bonds is observed between the proline carboxylate groups and the three uncoordinated water molecules.
  BLACKWELL PUBLISHING, English
  DOI：https://doi.org/10.1107/S1600536808010246
  DOI ID：10.1107/S1600536808010246, ISSN：1600-5368, Web of Science ID：WOS:000255450100061
• (-)545-fac -Δ- Tris(l-prolinato)cobalt(III) trihydrate　　　　　　　　　　　　　　　
  Masaru Kato; Miho Hayashi; Takashi Fujihara; Akira Nagasawa
  Acta Crystallographica Section E: Structure Reports Online, Volume：64, Number：5, First page：m684, 30 Apr. 2008
  The absolute configuration of the octa-hedral fac-CoN3O3 title complex, [Co(C5H8NO2)3]·3H2O, has been determined by single-crystal X-ray analysis. A three-dimensional network of hydrogen bonds is observed between the proline carboxyl-ate groups and the three uncoordinated water mol-ecules.
  English
  DOI：https://doi.org/10.1107/S1600536808010246
  DOI ID：10.1107/S1600536808010246, ISSN：1600-5368, SCOPUS ID：43149094863
• 化学修飾によるナノサイズクラスター金属錯体の高機能化　　　　　　　　　　　　　　　
  藤原 隆司
  Number：6(平成19年度), 2008
• 化学修飾によるナノサイズクラスター金属錯体の高機能化　　　　　　　　　　　　　　　
  藤原 隆司
  総合研究機構研究プロジェクト研究成果報告書, Number：6(平成19年度), 2008
• Anion influence on the coordination polymer structures of silver(I) complexes with 2-methylisothiazol-3(2H)-one　　　　　　　　　　　　　　　
  Masaru Kato; Takashi Fujihara; Daisaku Yano; Akira Nagasawa
  CRYSTENGCOMM, Volume：10, Number：10, First page：1460, Last page：1466, 2008
  Silver(I) coordination polymers formed by self-assembly of ambidentate ligands, 2-methylisothiazol-3(2H)-one (MI) and 5-chloro-2-methylisothiazol-3(2H)-one (CMI), have been characterized by single crystal X-ray analysis. The structure of the cation in [Ag-I(mu-O-mi)(2)] X (X = ClO4- (1); SbF6- (2)) is a one-dimensional chain while that in the nitrate salt, [Ag-2(I)(mu-O-mi)](NO3)(2) (3), is a three-dimensional network. A silver(I) complex with CMI, [Ag-I(mu-O-cmi)(2)] ClO4 (4), has also been synthesized and the cation has a one-dimensional chain structure. Although both MI and CMI have both O-and S-donor moieties, the oxygen atom dominantly coordinates to the silver(I) centre. The anion influence on the chain structure is attributed to the competition for the coordination ability between anions and MI, and the flexibility of the coordination sphere of d(10) silver(I) ion.
  ROYAL SOC CHEMISTRY, English
  DOI：https://doi.org/10.1039/b810652p
  DOI ID：10.1039/b810652p, ISSN：1466-8033, Web of Science ID：WOS:000259411200031
• ニオブ錯体触媒を用いたニトリル類の位置選択的環化反応　　　　　　　　　　　　　　　
  藤原 隆司
  Volume：第5号(18年度), First page：537, Last page：538, 2007
• ニオブ錯体触媒を用いたニトリル類の位置選択的環化反応　　　　　　　　　　　　　　　
  藤原 隆司
  総合研究機構研究プロジェクト研究成果報告書, Volume：第5号(18年度), First page：537, Last page：538, 2007
• Syntheses and X-Ray Structures of Novel Phenoxo-Bridged Binuclear Complexes: Bis(μ-Phenoxo)Bis[bis(Acetylacetonato)Chromium(III)] Complex and its Para-Substituted Phenoxo Analogs　　　　　　　　　　　　　　　
  Manabu Nakahanada; Takashi Fujihara; Akira Fuyuhiro; Sumio Kaizaki
  Inorganic Chemistry, Volume：31, Number：8, First page：1315, Last page：1316, 01 Mar. 1992
  English, Report scientific journal
  DOI：https://doi.org/10.1021/ic00034a003
  DOI ID：10.1021/ic00034a003, ISSN：1520-510X, SCOPUS ID：0005790713

• Concerto Redox Properties for Inorganic-Organic Hybrid Nanoclusters　　　　　　　　　　　　　　　
  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), 2011 - 2013
  FUJIHARA Takashi, Saitama University
  Grant amount(Total)：5460000, Direct funding：4200000, Indirect funding：1260000
  New inorganic-organic hybrid Nanoclusters were synthesized by using Zwitter ionic ligands and various metal ions. The synthesized clusters were clarified about their structures in the solid and in solution, the electrochemical properties, and the spectroscopy characters. The interactions between ligands and metals for multi-electronic redox system of electronic and structural characters were examined based on the obtained results. The electronic state and the analyses of their structures were carried out by also using the computational calculations. The new Zwitter ionic ligands that showed more complex multi electron redox system were developed. The evaluation of their functionality as the Nano-material was tried from these results. Thesis submission was done for a part of the result of obtaining, and the result was made public.
  Grant number：23510115
• Organo-chemical Functionalization of Nano-size Cluster Metal Complexes with Redox-active Ligands　　　　　　　　　　　　　　　
  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), 2008 - 2010
  FUJIHARA Takashi, Saitama University
  Grant amount(Total)：4420000, Direct funding：3400000, Indirect funding：1020000
  The nano-size metal cluster complexes which combined zwitterionic ligands with various kinds of metal ions were newly synthesized. The structure analyses for obtained complexes were carried out. The organo-chemical functionalization for obtained metal cluster complexes were carried out. The obtained functionalized materials were examined the structures, the electrochemical properties, and some spectral properties in solid state and in the solution.
  Grant number：20510093
• -　　　　　　　　　　　　　　　
  Competitive research funding
• -　　　　　　　　　　　　　　　
  Competitive research funding