Pd-Catalyzed Selective Arylative Cascade Cyclization of 1,6-Diynes and Dibenzoxaborins for Fused Naphthalene Derivatives

A palladium-catalyzed new mode of cascade arylative cyclization of 1,6-diynes is disclosed using dibenzoxaborin as an arylating agent featuring transmetalation and selective migratory insertion as the key steps. This process enables the efficient construction of polysubstituted fused naphthalene skeletons via the formation of three new C–C bonds through dual regioselectivity in both arylation as well as C–H functionalization. Some control experiments and kinetic isotope effect (KIE) studies were conducted to elucidate the reaction mechanism, and some product diversifications were achieved to showcase the synthetic potential.