Stereoselective Synthesis of trans -Stilbenes through Silver-Catalyzed Self-Coupling of N -Triftosylhydrazones: An Experimental and Theoretical Study.

A silver-mediated homocoupling of N -triftosylhydrazones for the construction of trans -stilbenes has been presented. This protocol is characterized by its suitability for both inter- and intramolecular reactions, operational simplicity, high efficiency with excellent stereoselectivity, broad substrate scope, and good functional group tolerance. A plausible mechanism involving nucleophilic attack of in situ generated sulfonium ylides on silver carbene was proposed on the basis of experimental results and DFT calculations, which further indicates that π-π stacking interactions play a dominant role in stereoselectivity control.