Rhodium-catalyzed addition reactions of benzylic C–H bonds to cyclic N-sulfonyl ketimines via π-coordination

Mannich-type reactions are a widely used method for the synthesis of amines due to the readily availability of nucleophiles and electrophiles. However, the inclusion of alkylarenes instead of active carbon pronucleophiles such as aldehydes and ketones in these addition reactions has been a challenge due to the inherent difficulty of benzylic deprotonation. In this study, we present a novel approach for the construction of N-sulfonyl amines via rhodium-catalyzed addition of unbiased benzylic C–H bonds to cyclic N-sulfonyl ketamines through π-coordination. This strategy enables the synthesis of a diverse range of N-sulfonyl amines, and subsequent diversification of the addition products showcases the synthetic potential of this protocol.