Phenyl migration in the molecular pyrolytic elimination of 1-chloro-2-methyl-2-phenylpropane in the gas phase

Abstract

The elimination of kinetics of 1-chloro-2-methyl-2-phenylpropane (neophyl chloride) in the gas phase were examined over a temperature range of 420–475 °C and a pressure range of 34–134 Torr. The reaction, in seasoned static vessels and in the presence of a free radical suppressor, is molecular in nature and follows a first-order rate law. The Arrhenius equation for the elimination was found to be: log(k₁/s^–1)=(13.47 ± 0.62)–(227.8 ± 8.7) kJ mol^–1(2.303RT)^–1. A Wagner–Meerwein phenyl migration was the prevailing pathway in the rearrangement process. This work provides strong evidence for an intimate ion-pair type of mechanism.