Base-promoted direct E-selective olefination of organoammonium salts with sulfones toward stilbenes and conjugated 1,3-dienes.

A base-promoted direct deaminative olefination of organoammonium salts was developed. Only mediated by KOtBu, a series of benzyl and cinnamyl ammonium salts reacted smoothly with sulfones, producing the valuable stilbenes and related 1,3-diene derivatives in good to high yields with good functional group tolerance and excellent E-selectivity. With this developed method, biologically active resveratrol and DMU-212 were also successfully prepared, which further demonstrates the practicality of this reaction.