Oxidation of 3,9-dimethylxanthine at stationary pyrolytic graphite electrode

Abstract

Electrochemical oxidation of 3,9-dimethylxanthine has been studied in the pH range 3.0–10.8 at stationary pyrolytic graphite electrode. A single 4e, pH dependent peak was observed. The charge transfer was followed by chemical reaction and various products were isolated. The aim of the study was to determine the effect of methyl groups on the oxidation mechanism. It was found that the electron releasing methyl groups at positions 3 and 9 completely alter the mechanism. A tentative EC mechanism for the oxidation is also suggested.