Rhodium(i)-catalyzed mono-selective C–H alkylation of benzenesulfonamides with terminal alkenes

Abstract

The Rh(I)-catalyzed ortho-alkylation of benzenesulfonamides with alkenes with the aid of an 8-aminoquinoline directing group is reported. The reaction is applicable to a variety of benzenesulfonamide derivatives and various alkenes. Curiously, unactivated 1-alkenes were more reactive than activated alkenes. Deuterium labeling experiments indicate that an unusual 1,2-H shift mechanism to generate a carbene rhodium intermediate is involved.