Inverse kinetic dependence on hydroxide in the reaction of hypochlorite with nitroethane

Abstract

In strong aqueous base, pH > 11, the catalysed chlorination of nitroethane (N) obeys the rate law, v=k[N]0[ClO–][OH–]–1. These kinetics are consistent with a rate-determining attack of either hypochlorite on the nitronic acid (A)kA= 1·8 × 108 l mol–1 s–1, or hypochlorous acid on nitronate (C–)k8≃ 1·5 × 105 l mol–1 s–1, at 25°C. A rationale is provided for the fact that the usual second-order kinetics for deprotonation of N do not apply to this halogenation of a nitro-alkane.