Kinetics of bromination of 1-hetera-4-cyclohexanones by N-bromosaccharin

Abstract

The kinetics of bromination of some substituted 4-piperidones and 4-selenanones by N-bromosaccharin in the presence of perchloric acid in aqueous acetic acid have been investigated. The bromination is first order in both substrate and H₃O⁺ and zero order in NBSA. A plausible mechanism based on these observations is proposed. The effects of the various substituents on the rates of bromination have been rationalized on the basis of their inductive and steric effects. The effect of solvent polarity on the rate has also been studied.