OHKI Yasuhiro Nagoya University, Graduate School of Science, Research Assistant, 大学院・理学研究科, 助手 (10324394)
MATSUMOTO Tsuyoshi Nagoya University, Graduate School of Science, Research Assistant, 大学院・理学研究科, 助手 (50311717)
久家 克明 名古屋大学, 物質科学国際研究センター, 講師(研究機関研究員)
|Budget Amount *help
¥53,300,000 (Direct Cost: ¥41,000,000、Indirect Cost: ¥12,300,000)
Fiscal Year 2003: ¥13,390,000 (Direct Cost: ¥10,300,000、Indirect Cost: ¥3,090,000)
Fiscal Year 2002: ¥18,460,000 (Direct Cost: ¥14,200,000、Indirect Cost: ¥4,260,000)
Fiscal Year 2001: ¥21,450,000 (Direct Cost: ¥16,500,000、Indirect Cost: ¥4,950,000)
During this research project, we have made substantial progress in many phases of research items, viz,
1. We have synthesized a novel rhenium selenido cluster, of [Cp^*Re(Se_3)(μ-Se_2)]_8, having a octa-nuclear diamond-crown shape of [Re(μ-Se_2)]_8 24-membered macrocyclic core, from the reaction of Cp^*ReCl_4 with 2-3 equiv of Li_2Se_5. On the other hand, the analogous reaction between Cp^*ReCl_4 and 2 equiv of Li_2Te_5 gave rise to a trinuclear cluster of a birdcage shape, Cp^*3Re_3Te_8.
2. A series of alkynethiolato complexes, alkyneselenolato complexes, diynethiolato complexes have been synthesized. These thiolate ligands are unique in that they carry unsaturated C-C bonds as substituents, and have shown interesting reactivity at various transition metal centers. For instance, we found unusual C-C coupling reactions, cyclic dimerizatino/trimerization of the functional carbon sites, C-S bond cleavage occurring at the thiolate ligands.
3. Thiolate-type sulfur is coordinated at transition
metal centers relatively strongly, while thioether-type sulfur forms weak M-S bonds, often exhibiting facile dissociation equilibration. We have utilized the mixed ligands RSCH_2CH_2S(-) (R=Et (etet), R=^iPr (^1ptet), R=Ph (ptet)) for assemblage of iron(II) and Ni(II) metal atoms. For instance, the 1:2 NiCl_2/Li(etet) reaction system gave rise to a linear polymer [Ni(etet)_2]_n, while the analogous 1:2 NiCl_2/Li(ptet) reaction resulted in formation of a cyclic hexamer [Ni_6(ptet)_<12>]. An interesting feature of these 1-dimensional polymers of Ni and Fe is that they can be dissolved in toluene by virtue of coordination of thioether-type sulfur atoms, and that the polymer structures are regenerated upon recrystallization.
4. A series of sulfido-bridged tungsten-ruthenium dinuclear complexes Cp^*W(μ-S)_3RuX(PPh_3)_2, Cp^*W(O) (μ-S)_2RuX(PPh_3)_2, and Cp^*W(NPh) (μ-S)_2RuX(PPh_3)_2 have been synthesized. The heterolytic cleavage of H_2 was found to proceed at room temperature upon treating Cp^*W(O) (μ-S)_2RuX(PPh_3)_2 and Cp^*W(NPh)(μ-S)_2RuX(PPh_3)_2 with NaBArF_4 under atmospheric pressure of H_2, which gave rise to [Cp^*W(OH)(μ-S)_2RuH(PPh_3)_2](BarF_4) and [Cp^*W(NHPh)(μ-S)_2RuH(PPh_3)_2](BarF_4), respectively. The mechanism of the heterolytic H_2 activation and the reverse H_2 evolution reactions have been investigated. Less