Solvent effect on kinetics of the chloride ion cleavage from anion radicals of 4-chlorobenzophenone

被引：14

作者：

Jaworski, JS ^{[1
]}

Leszczynski, P ^{[1
]}

机构：

[1] Univ Warsaw, Dept Chem, PL-02093 Warsaw, Poland

来源：

JOURNAL OF ELECTROANALYTICAL CHEMISTRY | 1999年 / 464卷 / 02期

关键词：

reductive cleavage; anion radicals; solvent effect; intrinsic rate constant;

D O I：

10.1016/S0022-0728(99)00043-1

中图分类号：

O65 [分析化学];

学科分类号：

070302 ; 081704 ;

摘要：

Formal potentials (expressed on the ferrocene scale) for the formation of 4-chlorobenzophenone anion radicals E(RX/RX.-)degrees as well as for the Cl-./Cl- couple increase with the solvent acceptor number but the second dependence is at least twice as strong. However, the rate constant for C-CI bond cleavage in these radicals decreases with solvent acidity, indicating that solvation of the leaving anion does not determine the kinetics of cleavage. It is shown that solvent effects on the intrinsic rate constant are dominant and can be described by the Pekar factor, as proposed in the Saveant model. (C) 1999 Elsevier Science S.A. All rights reserved.

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页码：259 / 262

页数：4

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