A stereo-controlled route to conjugated E-enediynes

Abstract

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 CuBr 2 to alkynes; (2) the Sonogashira coupling reaction of the dihalo vinyl derivatives with terminal alkynes to form conjugated enediynes.

Carbon nanotubes-supported palladium nanoparticles for the Suzuki reaction in supercritical carbon dioxide: A facile method for the synthesis of tetrasubstituted olefins

“…The starting dibromo-substituted olefins are generated from alkynes by exposure to CuBr 2 in refluxing acetonitrile [27] . This process can be easily directed toward high selectivity with the olefin templates, which products have been further confirmed by the NOE studies (Scheme 1).…”