Divergent reactivity of sulfoxonium ylide with allyl carbonate and allyl carbamate

A divergent reactivity of sulfoxonium ylide with allyl carbonates and allyl carbamates is demonstrated. Rh(iii)-catalyzed C-H activation and cyclization of sulfoxonium ylide with ally esters leads to the formation of a cyclopropane-fused tetralone derivative by cascade C-H activation, (4+2) annulation, and cyclopropanation. A similar reaction of sulfoxonium ylide with allyl carbamates forms a C3-substituted indanone derivative via a rare and interesting domino C-H activation and (4+1) annulation in which allyl carbamate is acting as a C1-synthon.