NUCLEOPHILIC-SUBSTITUTION REACTIONS OF TRIMETHYLSILYLMETHYL ARENESULFONATES WITH ANILINES AND BENZYLAMINES IN ACETONITRILE

The results of kinetic studies on the reactions of trimethylsilylmethy l arenesulfonates, 1 (Me3SiCH2OSO2C6H4Z), with anilines and benzylamin es in acetonitrile at 65.0-degrees-C are reported. The relatively larg e positive value of the cross-interaction constant between substituent s in the nucleophile (X) and leaving group (Z), rho(xz), indicates tha t the reaction proceeds by a S(N)2 process with a relatively tight tra nsition state. The enhanced rate of 1 compared with the rates for othe r corresponding carbon analogues leads us to conclude that the destabi lizing effect of the alpha-silyl group on the ground state of 1 due to geminal interaction is important not only for S(N)1 but also for S(N) 2 reactivities.