Palladium-Catalyzed Spirocyclization through C-H Activation and Regioselective Alkyne Insertion.

A Pd-catalyzed spirocyclization involving a sequential carbopalladation, intramolecular C-H activation, and a highly regioselective alkyne insertion to afford spirooxindoles and spirodihydrobenzofurans has been achieved. The spirocyclic products were generated in good to excellent yields with complete regiocontrol in a readily scalable procedure.