2013 Fiscal Year Final Research Report
Development of a highly reactive high-valent metal-oxo species and the oxidation catalysis
Project/Area Number |
24750052
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Research Category |
Grant-in-Aid for Young Scientists (B)
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Allocation Type | Multi-year Fund |
Research Field |
Inorganic chemistry
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Research Institution | University of Tsukuba |
Principal Investigator |
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Project Period (FY) |
2012-04-01 – 2014-03-31
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Keywords | オキソ錯体 / 電子移動 / 水素引き抜き反応 / 酸化反応 |
Research Abstract |
The formation of a mononuclear Cr(V)-oxo (1) complex was confirmed by ESI-MS spectrometry, electron paramagnetic resonance, UV-vis, and resonance Raman spectroscopies. The reduction potential (Ered) of 1 was determined to be 1.23 V vs SCE in acetonitrile based on the analysis of electron-transfer (ET) equilibrium between 1 and a one-electron donor. Reorganization energy of 1 was also determined to be 1.03 eV in ET reactions from phenol derivatives to 1 on the basis of the Marcus theory of ET. The reaction of 1 with various benzyl alcohol derivatives (BA) afforded corresponding 2e-oxidized products despite the higher oxidation potentials. In the case of trimethoxy-BA (Eox = 1.23 V) as a substrate, trimethoxy-BA radical cation was observed in the course of the reaction by UV-vis spectroscopy. It was revealed that the rate-determining step of the oxidation reaction was changed from one-step HAT to stepwise electron-proton transfer, depending on the redox potential of BA derivatives.
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Research Products
(5 results)