Copper-catalyzed coupling reactions of alkenyl halides with alkynes in the absence of palladium and ligand

We report herein copper(I)-catalyzed cross-coupling reactions of alkenyl halides with alkynes for the synthesis of 2-alkynyl-buta-1,3-dienes in good to excellent yields. This procedure is the first example for the synthesis of enynes catalyzed by catalytic amount of copper(I) alone in the absence of palladium and any ligand at relatively lower temperature.

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