The use of linear sweep voltammetry to study the addition of electrogenerated –CH2CN to aromatic carbonyl compounds

Abstract

A general electronalytical method for studying the rate of reaction between an electrogenerated species, e.g. nucleophile, base, electrophile, acid, or radical and an electroactive substrate is described. The method has been used to study the addition of electrogenerated ^–CH₂CN to aromatic carbonyl compounds. The cyanomethyl anion has been generated in two ways, (i) by reduction of azobenzene in acetonitrile, which involves protonation of the dianion by the solvent, and (ii) by reduction of cyanomethyltriphenyl-phosphonium and -arsonium cations in dimethylformamide, which involves reductive cleavage. A computer simulation of the electroanalytical experiments is described and representative results are given, including estimates of the rate constants for the addition of ^–CH₂CN to a series of alkyl phenyl ketones.