ELECTROCHEMICAL REACTIONS .22. INTRA-MOLECULAR TRAPPING OF RADICAL INTERMEDIATES IN THE REDUCTION OF ARYLSULPHONES

The cyclic sulphone (1) gives a radical ion which is stable in dimethylformamide on the time scale of cyclic voltammetry and the ortho-substituted diarylsulphone (3) shows only irreversible electrochemical behaviour. Either sulphone at the potential of the first reduction wave gave products which indicate decomposition of the radical anion by cleavage of a carbon-sulphur bond to form an aryl radical and sulphinate ion. The isolated products result from intramolecular trapping of the aryl radical intermediate.