Kinetic Study of the Catechols in the Presence of diethyl phosphite using N-hydroxyphthalimide as catalyst

The electrocatalytic oxidation of catechols in the presence of diethyl phosphite was performed using N-hydroxyphthalimide as catalysts. Initially, the oxidation- reduction of n-hydroxyphthalimide was investigated and the voltammetric results confirmed the production of relatively stable radical under electrochemical oxidation. Thereafter, the reactivity and electrocatalytic performances of generated radicals were investigated toward the various Catechols derivatives at different pH values. Based on these results the best electrocatalytic activity was observed at acetate buffer. The mechanism of electrochemical oxidation of catechols using N-hydroxyphthalimide as catalysts have been studied in the presence of diethyl phosphite as a nucleophile in aqueous solution. Voltammetric studies indicate that the quinones derived from catechols, and its derivatives, participate in michael addition reaction with diethyl phosphite. The reaction mechanism consists of electron transfer followed by a chemical reaction which is named as an EC mechanism. The homogeneous rate constants (kobs) were estimated by comparing the experimental cyclic voltammograms with the digitally simulated voltammograms based on ec mechanism. Also the effects of nucleophile concentration and substituted group of catechols on voltammetric behavior and the rate constants of chemical reactions were examined.The abstract should be typewritten for A4 format paper, maximum one page for all contributions.