RhI-Catalyzed Decarbonylative Spirocyclization via C–C Cleavage of Benzocyclobutenones: An Efficient Approach to Access Functionalized Spirocycles

摘要

We describe a rhodium-catalyzed all-carbon spirocenter formation through a decarbonylative coupling of trisubstituted cyclic olefins and benzocyclobutenones via C–C activation. A [Rh(CO)2Cl]2/P(C6F5)3 metal-ligand combination was found to catalyze this transformation most efficiently. A range of diverse spirocyclic rings were synthesized in good to excellent yields and many sensitive functional groups were tolerated. Mechanistic study supports the hydrogen-transfer process that occurs via a β-H elimination/decarbonylation pathway.