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The electrochemical oxidation of catechols (1) have been studied in the presence of diaza-18-crown-6 (DA18C6) (3a), diaza-15-crown-5 (DA15C5) (3b), and aza-15-crown-5 (A15C5) (3c) as nucleophiles in aqueous solution, by means of cyclic voltammetry and controlled-potential coulometry. The results indicate the participation of electrochemically generated o-benzoquinones (2) in Michael-type reaction with aza-crown ethers (3) to form the corresponding new obenzoquinone-aza-crown ether adducts (5). Based on ECE mechanism, the observed homogeneous rate constants (k obs ) of the reaction of o-bezoquinones (2) with aza-crown ethers (3) were estimated by comparing the experimental cyclic voltammograms with the digital simulated results. The calculated observed homogeneous rate constants (k obs ) was found to vary in the order DA18C6 > DA15C5 > A15C5.