Cyclic voltammetry at microdroplet modified electrodes.: A comparison of the reaction of vicinal dibromides with vitamin B12s at the liquid/liquid interface with the corresponding homogeneous process:: evidence for polar-solvent effects at the liquid/liquid interface

被引:31
作者
Davies, TJ
Garner, AC
Davies, SG
Compton, RG
机构
[1] Univ Oxford, Phys & Theoret Chem Lab, Oxford OX1 3QZ, England
[2] Univ Oxford, Dyson Perrins Lab, Oxford OX1 3QY, England
关键词
partially blocked electrodes; heterogeneous; homogeneous; microdroplets; liquid/liquid reactions; vitamin B-12;
D O I
10.1016/j.jelechem.2004.03.028
中图分类号
O65 [分析化学];
学科分类号
070302 ; 081704 ;
摘要
The electrocatalytic reactions of vitamin B-12s with three vicinal dibromides (cis-1,2-dibromocyclohexane, trans-1,2-dibromocyclohexane and 1,2-dibromobutane) are investigated in homogeneous and heterogeneous media. In the latter, cyclic voltammetry with basal plane pyrolytic graphite electrodes modified with microdroplets of dodecane + dibromide is employed to obtain kinetic parameters for the liquid/liquid reaction. The homogeneous and interfacial reactions exhibit marked differences in reactivity and the contrasting behaviour of the two systems suggests the liquid/liquid interface has a major role in the B-12s/R-Br2 reaction, consistent with a polar solvent effect. (C) 2004 Elsevier B.V. All rights reserved.
引用
收藏
页码:171 / 185
页数:15
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