Electrophilic Aromatic Substitution. 7. A Kinetic Study of the Aluminum Chloride Catalyzed Desulfonylative Benzylation of Aromatics with Phenylmethanesulfonyl Chloride in Nitromethane

William D. Covey, Franklin P. DeHaan, Gerald L. Delker, Steven F. Dawson,

Peter K. Kilpatrick, Gail B. Rattinger, and William G. Read

Department of Chemistry, Occidental College, Los Angeles, California 90041

Received December 28, 1983

Kinetic studies have been made of the AlC13-catalyzed reaction of phenylmethanesulfonyl chloride with benzene or toluene in nitromethane at 20 °C. The reaction follows first-order dependence upon phenylmethanesulfonyl chloride and catalyst but zero-order dependence upon aromatic hydrocarbon. It is proposed that the reaction involves a benzyl cation which is formed in situ. Competitive result are also reported for the reaction with (p-chloropheny1)methanesulfonyl chloride. In both cases, the relative reactivities, k_T/k_B, and toluene isomer product distributions appear to be exceptions to Brown's selectivity relationship.