Stereoselective Addition of a Lithium Anion of 1,1-Diphenyl-2-aza-pentadiene to Sulfinimines: Application to the Synthesis of (−)-Epiquinamide

The addition of a lithium anion of diphenylallylimine to nonracemic sulfinimines was investigated. It was found that the reaction with sulfinimines derived from aliphatic aldehydes afforded the products with excellent diastereoselectivity (>99:1), furnishing the product vicinal diamines in very good yields. Application of the formed product vicinal diamines was demonstrated in the total synthesis of the natural product (−)-epiquinamide.