Rh(III)‐Catalyzed C−H Activation/O‐Annulation for Construction of Divergent Spirosuccinimide and Maleimide‐Fused Isochromenes

Abstract A rhodium‐catalyzed [5+1] cycloaddition via C−H activation/ O ‐annulation strategy for synthesizing biologically interesting isochromenes is presented. This protocol selectively provides divergently functionalized isochromenes containing spirosuccinimide and maleimide scaffolds according to the maleimides and itaconimides used as the substrates. This methodology exhibits an extensive substrate scope, remarkable functional group tolerance, and high regioselectivity.