Stereoselective Synthesis of (+)-α-Conhydrine from R-(+)-Glyceraldehyde

Stereoselective synthesis of (+)-α-Conhydrine was accomplished from protected (R)-(+)-glyceraldehyde, a familiar carbohydrate predecessor. Our synthetic strategy featured the following two key reactions. One is Zn-mediated stereoselective aza-Barbier reaction of imine 6 with allyl bromide to afford chiral homoallylic amine 7, and the other is ring-closing metathesis.