Asymmetric Conjugate Addition to α,β-Unsaturated Chiral Sulfinyl Imines

Significance

Asymmetric 1,4-addition to enones is a very versatile method of the enantioselective construction of a new C-C bond. tert-Butyl sulfinimines are easily removable chiral auxiliaries which allow a number of useful synthetic transformations. This work represents a practical method for the enantioselective 1,4-addition of an alkyl group to α,β-enones mediated by organocopper reagents. Moderate to good diastereoselectivities of the resulting Michael adducts can be achieved by this approach. The addition products can be hydrolyzed to ketones or aldehydes, or used in further transformations employing the chiral tert-butanesulfinyl imine chemistry.