Electroreduction of 5-Arylazomethineindazole derivatives in ethanolic buffer solutions at mercury electrodes

ABSTRACT

Electrochemical behaviour of 5-arylazomethineindazole compounds is studied using DC-polarography, cyclic voltammetry and coulometry. The symmetry coefficient [alpha] and number of electrons [n] consumed in the electrochemical reaction are evaluated, as well as the kinetic parameters [k[s], Delta G] calculated from the cyclic voltammetry data. The medium and substituent effects on the electrode reaction are examined. The mechanism of the electroreduction of the above compounds has been predicted. It involves 4e[-], 5H[+] in acid media, leading to cleavage of the azomethine centre, compared to 2e[-], 2H, in neutral and alkaline media, resulting in the saturation of the [-]C = N- bond