2006 Fiscal Year Final Research Report Summary
Reaction Control of Dynamic Complexes. TheoretirAl Study
| Project/Area Number |
14078221
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| Research Category |
Grant-in-Aid for Scientific Research on Priority Areas
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| Allocation Type | Single-year Grants |
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| Review Section |
Science and Engineering
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| Research Institution | Kyoto University |
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Principal Investigator |
SAKAKI Shigeyoshit Kyoto University, Department of Molecular Engineering, Professor, 工学研究科, 教授 (20094013)
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| Project Period (FY) |
2002 – 2005
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| Keywords | Theoretical study / Transition-metal complexes / Bonding nature / Reaction mechanism / Reactivity control / Geometry / Reactivity / Electronic structure |
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| Research Abstract |
Geometries and reaction behavior of dymamic complexes including transition metal elements were theoretically investigated to clarify how electronic structure detennines geometry and reactivity with DFT and post-Hariree-Fock methods such as MP2 to MP4(SDQ) and CCSD(T) methods. One of the important results is the bonding nature and binding energy of the transition metal complexes with large p-conjugate systems such as C60, corannulene, and sumanene. The DFT method underestimates the binding energy in Pt(0), Ir(I), and similar complexes and the best way now is to employ the ONIOM method, in which the MP4(SDQ) is used for important moiety and the MM method with UFF force field is used for whole molecule. We successfully presented reasonable binding energies of these complexes and proposed that various complexes can be synthesized for corannulene and sumanene. Also, important result is presented on the transition-metal catalyzed synthetic reaction such as Ir-catalyzed direct borylation of benzene with diborane. This reaction takes place through the oxidative addition to Ir(III)-tris bowl active species followed by reductive elimination of bowlbenzene. The important point is that the active species is Ir(III) species and the catalytic cycle involves the Ir(V) intermediate. Also, we theoretically investigated H-H bond activation by S-bridged dinuclear Ru-W complex, which is an interesting model of hydrogenase. The activation reaction takes place through heterolytic sigma bond activation, which is different from the usual oxidative addition reaction. This result clearly shows that the S-bridge Ru-W dinuclear complex is a good functional model ofhydrogenase.
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