Expedient construction of fused polycyclic skeletons via palladium-catalyzed dearomatization of naphthalenes and benzenes.

A novel palladium-catalyzed dearomative cyclization of naphthalenes and benzenes has been accomplished for expedient construction of fused polycyclic skeletons bearing an all-carbon quaternary center. Excellent functional group tolerance was demonstrated in the reaction of 2,2-phenylnaphthyl acetonitriles, in which cyano group can serve as linkage for potential applications. Further, the challenging dearomatization of benzenes was developed, offering a series of [6,5,6]-carbotricyclic scaffolds which may play a role as intermediate for the synthesis of fused tricyclic natural products and its analogues.