Rhodium-Catalyzed C–H Activation/Annulation of N -Chlorobenzamide Derivatives with Alkynes

High Resolution Image Download MS PowerPoint Slide Highly efficient synthesis of isoquinolones is achieved by a Rh(III)-catalyzed C–H activation/annulation of N -chlorobenzamide derivatives with alkynes. This transformation leverages the N -Cl moiety as a highly effective internal oxidant, enabling the reaction to proceed smoothly under mild conditions and delivering the target products in excellent yields (up to 98% yield). Control experiments further reveal the superior oxidizing ability of the N -Cl benzamide relative to its N -OMe and N -OPiv analogues. Notably, the reaction proceeds with 85% yield even at an exceptionally low catalyst loading of 0.05 mol %.