Asymmetric synthesis of chiral amines by highly diastereoselective 1,2-additions of organometallic reagents to N- tert-butanesulfinyl imines

Abstract

High yielding and highly diastereoselective methods for 1,2-additions of organometallic reagents to N- tert-butanesulfinyl aldimines ( 2) and N- tert-butanesulfinyl ketimines ( 3) are described. The additions of alkyl, aryl, alkenyl, and allyl carbanions to a diverse set of imines with different steric and electronic properties are demonstrated. Acidic methanolysis of the sulfinamide products ( 4 and 6) delivers highly enantioenriched α-branched and α,α-dibranched amines. Since a broad range of sulfinyl imines are easily accessible from aldehydes and ketones, a wide variety of enantioentriched amines may be prepared.