Enantioselective β-vinylation of α,β-unsaturated aldehydes using a β-nitroethyl sulfone as vinyl anion equivalent
A concise method for the asymmetric β-vinylation of enals is presented. The success of the reaction lies in the stereoselective organocatalyzed addition of β-nitroethyl sulfone 1 to enals and in the ability of Mg to promote the concomitant elimination of the sulfone moiety and the nitrous acid. The method performed in a three-step one-pot operation allows the synthesis of enantioenriched β-vinyl aldehydes and derivatives thereof. Copyright