Electrochemical investigations on several dimethylbenzo[ a]pyrenes

Abstract

Electrochemical studies on several dimethylbenzo[ a]pyrene (DMBP) 1 derivatives were carried out at a platinum disk electrode employing cyclic voltammetric and chronopotentiometric techniques in (1:1) acetonitrile-benzene mixed solutions with tetra- n-butylammonium perchlorate as a supporting electrolyte. The results indicate that DMBPs undergo reversible one-electron oxidations and reductions to form the cation radical and the radical anion respectively as electrode products. The stability of the cation radicals of 1,3-, 2,3-, and 3,6-DMBPs is determined by the current reversal chronopotentiometric method in the medium studied at room temperature, and the pseudo-first-order decay rate constants of these radical species are 0.00046, 0.061, and 0.090 s −1, respectively. Reactions of cation radicals with nucleophiles such as water and pyridine were also studied electrochemically and the result is described.