Cathodic syntheses of tin alkyls—I. Reduction of acrylonitrile in aqueous alkali

Abstract

The electrochemical behaviour of a tin cathode in alkaline solutions of acrylonitrile has been investigated by studying polarisation curves and product analysis. The only interpretation which is consistent with these and earlier observations involves a mechanism for the reduction of acrylonitrile in which adsorbed cyanoethyl radicals are the key intermediates. At low acrylonitrile concentrations those radicals activate the surface towards hydrogen evolution, at intermediate concentrations inhibit it, and at high acrylonitrile concentrations enable tin atoms to be extracted from the surface with the formation of tetracyanoethyl tin. The yield of this product is favoured by using saturated solutions of acrylonitrile and low negative potentials.