PHENYL MIGRATION IN THE MOLECULAR PYROLYTIC ELIMINATION OF 1-CHLORO-2-METHYL-2-PHENYLPROPANE IN THE GAS-PHASE

The elimination of kinetics of 1-chloro-2-methyl-2-phenylpropane (neop hyl chloride) in the gas phase were examined over a temperature range of 420-475-degrees-C and a pressure range of 34-1 34 Torr. The reactio n, in seasoned static vessels and in the presence of a free radical su ppressor, is molecular in nature and follows a first-order rate law. T he 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-M eerwein phenyl migration was the prevailing pathway in the rearrangeme nt process. This work provides strong evidence for an intimate ion-pai r type of mechanism.