3-Ene-1, 5-diynes are important components of many enediyne antitumor agents and luminescent materials. A stereo-controlled approach to the synthesis of E-enediynes was developed, and it consists of the following two steps: (1) a mild and economical synthesis of dihalo vinyl derivatives via addition of CuBr2 to alkynes; (2) the Sonogashira coupling reaction of the dihalo vinyl derivatives with terminal alkynes to form conjugated enediynes.