Chemical and electrochemical oxidation of different catechols were studied in the presence of N,N'diethylethylenediamine in phosphate buffer solution, using cyclic voltammetry, constantcurrent cou lometry and controlledpotential coulometry. The quinones derived from catechols participate in Michael addition reactions with N,N'diethylethylene diamine via the ECECE mechanism to form the correspond ing new diethyltetrahydroquinoxalinedione derivatives
