The participation of aromatic neighboring groups in gas‐phase elimination reactions

Abstract

Abstract The gas‐phase pyrolysis of 2‐chloroethylbenzene and p ‐methoxy‐2‐chloroethylbenzene was studied in a static system over the temperature range of 411°–471°C and a pressure range of 39–202 mm Hg. The reactions in seasoned vessels, with the propene inhibitor always present, were homogeneous, first‐order, and unimolecular. The rate constants are given by the Arrhenius equation for 2‐chloroethylbenzene: and for p ‐methoxy‐2‐chloroethylbenzene: The presence of phenyl substituents in the β position of ethyl chloride has been found to provide anchimeric assistance in these elimination reactions.