Asymmetric Synthesis of Ethoxydienamines in Superbasic MediumMediated by Chiral Sulfinyl Group

ABSTRACT: The direct addition of metalated alkoxydiene 2, obtained from R,β-unsaturated acetal 1 through a LIC-KORpromoted conjugated elimination reaction, to enantiopure sulfinimines 3 (both R and S N-sulfinyl imines) afforded Nsulfinyl alkoxydienyl amines 4 with high diastereoselectivity. Functionalized enantiopure alkoxydienyl amines 5 were then easily obtained upon the selective removal of the chiral auxiliary under mild conditions. Moreover, the further hydrolysis of the alkoxydienyl moiety gave access to protected enantiopure β-keto amines 7.