Kinetics and mechanism of oxidation of diethyl ketone by N‐bromosuccinimide

Abstract

AbstractOxidative kinetics of diethyl ketone in perchloric acid media in the presence of mercuric acetate have been studied by using N‐bromosuccinimide (NBS) as oxidant in the temperature range of 25°‐50°C. It has been found that the order with respect to NBS is zero while with respect to diethyl ketone and [H+], it is unity. Succinimide, sodium perchlorate, and mercuric acetate have an insignificant effect on the reaction rate, while the dielectric effect was negative. A solvent isotope effect (k0D2O/k0H2O = 1.6–1.8) at 35°C has been observed. On the basis of the available evidences a suitable mechanism consistent with the experimental results has been proposed in which it is suggested that the mechanistic route for NBS oxidation in an acidic medium is through the enol form of the ketone. The magnitude of the solvent effect also supports the mechanism. Various activation parameters have been calculated, and the 1,2‐dicarbonyl compound has been identified as the end product of the reaction.