Copper-Catalyzed Enantioselective Henry Reaction of β,γ-Unsaturated α-Ketoesters with Nitromethane in Water.

A highly enantioselective Henry reaction of β,γ-unsaturated α-ketoesters with nitromethane in water by virtue of chiral copper complexes has been developed. A series of unsaturated β-nitro-α-hydroxy esters bearing tetrasubstituted carbon stereocenters were obtained exclusively with high yields and excellent enantioselectivities. This method could avoid tedious anaerobic anhydrous manipulation and reduce the environmental pollution caused by organic solvents.