Ligand-accelerating low-loading copper-catalyzed effective synthesis of (E)-1,3-enynes by coupling between vinyl halides and alkynes performed in water

The useful conjugated enynes could be easily prepared via low-loading (0.0001 mol %) copper-catalyzed coupling between vinyl halides and terminal alkynes. It is noteworthy that this reaction could be preformed in water without using any co-solvents and the desired 1,3-enynes could be obtained with good yields. In the catalytic reaction, ligand-acceleration effect was markable.