Mechanism of H2 Evolution from a Photogenerated Hydridocobaloxime

被引：207

作者：

Dempsey, Jillian L. ^{[1
]}

Winkler, Jay R. ^{[1
]}

Gray, Harry B. ^{[1
]}

机构：

[1] CALTECH, Beckman Inst, Pasadena, CA 91125 USA

来源：

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY | 2010年 / 132卷 / 47期

基金：

美国国家科学基金会;

关键词：

STATE PROTON-TRANSFER; COBALOXIME CATALYSTS; HOMOGENEOUS SYSTEM; HYDROGEN EVOLUTION; ELECTRON-TRANSFER; COMPLEXES; KINETICS;

D O I：

10.1021/ja109351h

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Proton transfer from the triplet excited state of brominated naphthol to a difluoroboryl bridged Co-I-diglyoxime complex, forming (CoH)-H-III, was monitored via transient absorption. The second-order rate constant for (CoH)-H-III formation is in the range (3.5-4.7) x 10(9) M-1 s(-1), with proton transfer coupled to excited-state deactivation of the photoacid. (CoH)-H-III is subsequently reduced by excess Co-I-diglyoxime in solution to produce (CoH)-H-II (k(red) = 9.2 x 10(6) M-1 s(-1)), which is then protonated to yield Co-II-diglyoxime and H-2.

引用

收藏

页码：16774 / 16776

页数：3

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