Kinetic study of the decomposition of N-chloramines

The decomposition of various N-chloroalkylamines and N-chloroalcoholamines was investigated kinetically at pH 4-12 and in strongly alkaline media, The rate of N-chloramine decomposition increased with increasing pH above pH 10, remained virtually constant over the pH range 7-10 and again increased with decreasing pH in the acidic zone, The results are described by a rate equation involving general base catalysis terms. Experimental evidence suggests that the decomposition of N-haloamines proceeds via an elimination mechanism that yields an imine. This beta-elimination process is a non-synchronized concerted mechanism where cleavage of the N-X bond has progressed to a greater extent than that of the C-a-H by the time the transition state is reached, which is therefore 'E1-like' (ia. with a transition state having a certain nitrenium character).