Rhodium-catalyzed divergent dehydroxylation/alkenylation of hydroxyisoindolinones with vinylene carbonate

Herein, a novel organic transformation involving rhodium-catalyzed divergent dehydroxylation/alkenylation of hydroxyisoindolinone with vinylene carbonate is reported, and a series of architecturally rigid and widely used spirolactams are obtained with excellent functional group tolerance and high selectivity. Remarkably, the promising vinylene carbonate reagent presents a distinct chemical reactivity as a vinyl-oxygen cyclic synthon and first transfers the C–H bond to spiroheterocycle scaffolds. Moreover, another chemoselectivity, direct dehydrogenative coupling with vinylene carbonate, is also presented. This protocol is compatible with green chemistry and only releases H₂O and CO₂ as byproducts.