Kinetics of Oxidation of Pyridoxine by Chloramine-T in Acid Medium

Article abstract of DOI:10.1246/bcsj.60.4395

The kinetics of oxidation of pyridoxine (PRX) by chloramine-T (CAT) in the presence of hydrochloric acid (0.04-1.14 M) have been studied over teh temperature range of 303-323 K.The rate of the reaction shows first-order dependence on each of CAT, PRX, and chloride ion concentrations.The reaction rate is independent of hydrogen ion concentration.Variations of ionic strength and dielectric constant of the medium have negligible effect on the rate.Addition of the reaction product, p-toluenesulfonamide, decreases the rate showing a negative first order dependence.The solvent isotope effect has been studied by using heavy water.The activation parameters, E_a, ΔH<*>, and ΔS<*> are computed from the reaction rates at various temperatures.The mechanism of PRX oxidation proposed and the rate law derived are consistent with the observed kinetics.