Bimetallic Pd/Cu‐Catalyzed Sonogashira Coupling‐Elimination Reaction: An Efficient Synthesis of 2‐Unsubstituted Terminal 1, 3‐Enynes

Herein, an efficient strategy to synthesize 2-unsubstituted terminal 1, 3-enynes in high yields by bimetallic Pd/Cu-catalyzed Sonogashira coupling-elimination reaction of iodobenzenes with 4-bromobut-1-yne was reported. To our knowledge, this is the first report of 4-bromobut-1-yne as an efficient 1, 3-enynes reagent, and the method is more convenient and cost-effective than other reported synthetic methods, which are hindered by the laborious preparation of starting materials, the high cost of bromoethene, and the inconvenient handling of gas acetylene.