Second-versus third-order kinetics in the base-catalysed halogenation of di-isopropyl ketone

Abstract

The rate law for the title process in water at pH > 11 has the form v=k[CH][OH^–][OX^–] where CH represents a weak carbon acid and X a halogen. The rate constants for hypobromite and hypochlorite ions at 25·3°C are 19·4 and 0·061 l² mol^–2 s^–1, respectively. The concept of an equipartition concentration, [OX^–]_ec, for equal second- and third-order rates is developed and used to clarify problems and discrepancies in the literature.