Catalytic Asymmetric Synthesis of γ-Substituted Vinyl Sulfones

A fast new entry for the stereoselective construction of gamma-substituted vinyl sulfones is presented. The key for success is the use of a readily available chiral secondary amine catalyst that allows the use of base-sensitive beta-nitroethyl sulfones as masked beta-sulfonyl vinyl anions in conjugate additions. The method performed in a three-step one-pot operation gives access to a great variety of vinyl sulfones in good yields and with excellent enantioselectivities. The method has also been extended to other relatively base-sensitive beta-electron-withdrawing-substituted nitroalkanes to afford products with manifold functionality, providing a quick entry to very attractive synthetic intermediates for organic synthesis.