An Easy Stereoselective Copper(I)-Catalyzed Synthesis of (E)-3-Trifluoromethylbut-2-en-3-ynoate via Palladium-Free Stille Coupling Reaction
Résumé
A general and efficient Cu(I)-catalyzed cross-coupling reaction of alkynyl bromides and beta-tributylstannyl-alpha, beta-unsaturated ester bearing a trifluoromethyl group in beta-position was developed under very mild conditions. This method provides easy access to a variety of 2,3-enynoate bearing a trifluoromethyl group from good to excellent yields with excellent stereoselectivity. This procedure does not require the use of any expensive supplementary additives and is palladium-free.