Electrochemical oxidation of catechol has been studied in the presence of imidazole asrnnucleophile in aqueous solution, using cyclic voltammetry. The results indicate thernparticipation of catechol in 1, 4- Michael reaction with imidazole to form the correspondingrncatechol thioethers. Based on the observed EC mechanism, the homogeneous rate constantsrn(kfcal) of the reaction of o-benzoquinone with imidazole were estimated by fitting therntheoretical working curve with the experimental working curve.rnKey words: EC mechanism, cyclic voltammetry, catechol and imidazole.