Development of practical oxidation catalysts based on bistabilty that promotes reversible O-O bond scission

2016 Fiscal Year Final Research Report

• Project/Area Number: 26288027
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Inorganic chemistry
• Research Institution: Doshisha University
• Principal Investigator: Kodera Masahito 同志社大学, 理工学部, 教授 (00183806)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 非ヘム二核鉄酵素 / 可溶性メタンモノオキシゲナーゼ / カルボキシラトリッチな二核化配位子 / 酸化触媒 / 二核鉄錯体 / パーオキソ二核鉄(III)錯体 / オキソジオキソ二核鉄(IV)錯体 / アルカン水酸化

Outline of Final Research Achievements

We clarified mechanism of dioxygen activation by diiron complex on the basis of resonance Raman and electronic absorption spectral studies, detailed kinetic studies, DFT calculations, kinetic isotope effect (KIE), and catalytic oxidation of alkane. The rate constants increased proportionally to the substrate concentration in low substrate concentration. In high substrate concentration, however, the rate constants converge to the same value regardless of the kind of substrate. This is explained by a two-step mechanism, where anti-oxodioxodiiron(IV) is formed via syn-to-anti transformation of the syn-dioxo form, and reacts with substrate as the oxidant. The anti-dioxo form is 620-fold more reactive in the C-H bond cleavage of ethylbenzene than the most reactive diiron system reported so far. The KIE with toluene/D8-toluene is 95 at -30°C, and the largest in diiron systems reported so far. The diiron complex efficiently catalyzes the oxidation of various alkanes with H2O2.

Free Research Field

錯体化学