A Rh(iii)-catalyzed C–H activation/regiospecific annulation cascade of benzoic acids with propargyl acetates to unusual 3-alkylidene-isochromanones

Abstract

A Rh(III)-catalyzed C–H activation and regiospecific annulation cascade of benzoic acid with propargyl acetate was developed to produce an unreported 3-alkylidene-isochromanone scaffold. The biggest merit of this reaction is achieving the regioselective control in the alkyne insertion and the precise removal of the acetyl group to eventually form 3-alkylidene-isochromanone scaffolds possessing an unusual exocyclic double bond with moderate to excellent yields (up to 93%) under mild temperature along with broad generality and versatility.