TECHNICAL PAPERS ELECTROCHEMICAL SCIENCE AND TECHNOLOGY Electrochemical Reduction of Aromatic Sulfinic Acids in Dimethylsulfoxide

The electrochemical reduction of benzenesulfinic, p-toluenesulfinic, and p-nitrobenzenesulfinic acids was studied in dimethylsulfoxide solutions. From cyclic voltammetry experiments, a chemical reaction following the first electron trans-fer was detected during the reduction process. A cyclic voltammetry technique using ultramicroelectrodes has provided kinetic parameters for the electron-transfer steps, from which it was possible to observe the influence of the ring sub-stituent on the electrochemical reduction. The mechanism of the electroreduction of aromatic sulfinic acids in dimethyl-sulfoxide depends upon the nucleophilic attack of the radical anion produced on the starting compound during the reduc-tion processes