Concurrent solvolytic and non-solvolytic reactions of benzyl azoxytoluene-p-sulphonate in aqueous trifluoroethanol containing bases: an unprecedented mechanistic duality

Abstract

Benzyl azoxytoluene-p-sulphonate (1) undergoes heterolytic fragmentation on solvolysis with the anticipated electron flow from benzyl towards the toluene-p-sulphonate leaving group, but suffers concurrent nucleophilic attack by basic solutes at the sulphur atom of the toluene-p-sulphonate moiety with consequent heterolysis and electron flow in the opposite sense, the benzylazoxy group now being the nucleofuge.