Oxidative ring cleavage of 4-(4-R-phenyl)-1,2,4-triazolidine-3,5-diones: Electrochemical behavior and kinetic study
Abstract
Cyclic voltammetry results as a diagnostic technique for electrochemical oxidation of 4-(4-R-phenyl)-1,2,4-triazolidine-3,5-diones (1-5) are reported and discussed. The results indicate that the electrochemically generated 4-(4-R-phenyl)-4H-1,2,4-triazole-3,5-diones (1ox-5ox) are unstable and participate in oxidative ring cleavage. In this study, the effect of different parameters such as pH, 4-phenylurazole concentration, solvent, temperature, substitute effect and time window of chosen electrochemical method have been studied. Also, the transfer coefficient, α, exchange current density, J0, the formal potential, E0’ and diffusion coefficient, D, of 4-phenylurazole (1) have been calculated. In addition, the observed homogeneous rate constants of oxidative ring cleavage of 4-phenylurazole derivatives were estimated by comparing the experimental cyclic voltammetric responses with digital simulated results.