Highly Enantioselective Addition of Phenylacetylene to Ketones Catalyzed by BisT(hydroxycamphorsulfonamide) -Copper(II) Complex

A chiral copper complex, generated from a C2-sym­metric bis(hydroxycamphorsulfonamide) ligand (8 mol%) and Cu(OTf)2, has been discovered to effect high enantioselectivities in the addition of alkynylzinc to a series of simple ketones. The alkynylation of a variety of aromatic and aliphatic ketones resulted in excellent yields and enantioselectivities (83-98% ee). Even when the loadings of the catalyst is 5 mol%, up to 94% ee was obtained.