Stereoselective synthesis of α-phenylchalcogeno-α,β-unsaturated esters

Ethyl α-phenylchalcogeno α,β-unsaturated esters were prepared in a stereoselective manner by the reaction of ethyl propiolates with organocuprates, followed by the reaction with the appropriate electrophilic organosulfur, organoselenium or organotellurium source.