Palladium-Catalyzed Asymmetric Cross-Coupling Reactions of Cyclobutanols and Unactivated Olefins.

Transition-metal-catalyzed activations of carbon-carbons bonds of small strained rings have widespread applications in synthetic and medicinal chemistry. However, coupling reactions of cyclobutanols involving β-carbon elimination to construct C(sp)-C(sp) bonds have scarcely been developed. Here, we demonstrate a highly enantioselective Pd-catalyzed intermolecular C(sp)-C(sp) coupling reaction of a broad range of cyclobutanol derivatives and unactivated alkenes, allowing convenient access to a series of chiral benzene-fused cyclic compounds in a highly regio-, chemo-, and enantioselective manner.