Oxidation of chalcones by N - chloronicotinamide in aqueous acetic acid medium: A kinetic and mechanistic study

The kinetics and oxidation of chalcones by N - chloronicotinamide has been studied in 80% acetic acid – 20% water (v/v) containing HCl and NaClO4 in the temperature range between 307 and 319K. The reaction rate follows first order and zero order dependence with respect to [NCN] and [chalcone] respectively. The reaction is catalyzed by hydrogen ions. The rate increases with increase in the percentage of acetic acid and the plot of log kobs versus 1/D is linear with a positive slope indicating the positive ion – dipole nature of the reaction. Variation of ionic strength and addition of the reaction product, nicotinamide has no effect on the rate. The product of oxidation is benzoic acid. A suitable mechanism consistent with the observed kinetics has been proposed.

Share This Article