Electrochemical oxidation of catechols in the presence of acetylacetone

Electrochemical oxidation of catechols (1a–1c) has been studied in the presence of acetylacetone (3) as a nucleophile in aqueous solutions, using cyclic voltammetry and controlled-potential coulometry. The results indicate that the quinones derived from catechols (1a–1c) participate in Michael addition reactions with acetylacetone (3) to form the corresponding benzofurans (6a–6c). In this work we have proposed a mechanism for the electrode process. The electrochemical synthesis of benzofurans 6a–6c has been successfully performed at carbon rod electrodes and in an undivided cell.