Electrooxidation products of methylindoles: Mechanisms and structures

Electrochemical oxidation of 1-methylindole, 2-methylindole and 3-methylindole on a platinum anode in acetonitrile containing NaClO4 has been studied. In any case no polymeric deposit on the working electrode was obtained. The identification of the obtained soluble products is described and the mechanisms of formation are discussed, Analogously to the case of unsubstituted indole, electrooxidized 1-3 react through positions 2 and 3. The non polymerization of 1 is explained with the formation of a tetramer which is oxidized to a stable radical cation and dication without undergoing further coupling reactions. Copyright (C) 1996 Elsevier Science Ltd