Journal of the American Chemical Society, Vol.136, No.12, 4472-4475, 2014
Palladium-Catalyzed Intramolecular Asymmetric C-H Functionalization/Cyclization Reaction of Metallocenes: An Efficient Approach toward the Synthesis of Planar Chiral Metallocene Compounds
A palladium-catalyzed asymmetric synthesis of planar chiral metallocene compounds is reported. The reaction stereoselectively functionalized one of the ortho C-H bonds of Cp rings by intramolecular cyclization to form indenone derivatives in high yields with excellent enantioselectivity. The mild set of reaction conditions allowed a wide variety of chiral metallocene compounds to be synthesized with broad functional group tolerance. The influences of preinstalled chiralities on the other Cp-ring were also investigated.