Kinetics and Mechanistic Studies of the Bromination of some Derivatives of 1,3-diaryl-2-propen-1-one

Abstract

The rate of bromination of 1,3-diaryl -2-propen-1-one (a1) and its derivatives p-bromo acetophenone (a2), p-chloro acetophenone (a3), p-methoxy acetophenone (a4), p-nitro acetophenone (a5), p-chloro benzaldehyde (a6) and p-nitro benzaldehyde (a7) had been studied in chloroform. The study indicated first order dependence on each of reactants with rates (a5 > a3 > a2 > a1 > a4 ) and (a1 > a7 > a6) at any temperature. The effect of substituents on the rate showed that electronic factors, inductive and conjugative effects play a reasonable role on the stability of the intermediates. Suggested mechanisms, which are consistent with the results have been postulated and suitable rate laws in consonance with the suggested mechanisms have been derived.