Convolutive voltammetric studies on some N-benzylsulfonyl-3,5-dimethyl-4- arylazopyrazole and some of its derivatives at a mercury cathode

Chemistry Department, Faculty of Science, Tanta University, Tanta, Egypt

Manuscript received 26 October 1999, revised 15 September 2000, accepted 21 September 2000

The reduction of some N-benzylsulfonyl-3,5-dimethyl-4-arylazopyrazoles and some of its derivatives (p-Br, p-N(CH₃)₂) has been studied using polarography, cyclic voltammetry, chronocoulometry and chronopotentiometly techniques in 40% ethanolicB.R. buffer series (pH 2.5-11.1) at a mercury cathode. Two electrons are consumed in the electroreduction of N=N center confirmed by controlled potential coulometry experiment. The chemical and electrochemical parameters have been tested by comparing the experimental voltammograms with simulated data. Convolutive cyclic voltammetry indicates that the electrochemical reaction mechanism proceeds via EC_irrev process.