Reactions of silver ions with thiobenzamides in aqueous solution

Abstract

In aqueous acid solution, in the presence of an excess of silver ions, thiobenzamides form 1 S-amide : 1 Ag⁺ complexes stoicheiometrically. For thiobenzamide the decomposition of the 1 : 1 complex leads to silver sulphide and benzonitrile and for N-cyclohexylthiobenzamide to silver sulphide and the O-amide. For both thiobenzamide and N-cyclohexylthiobenzamide the kinetic forms suggest mechanism of decomposition similar to those proposed for the corresponding decompositions of S-amide–Hg²⁺ complexes. These mechanisms involve the ionisation of the S-amides′N-hydrogen atoms.