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Copper-catalyzed trans-carbohalogenation of terminal alkynes with functionalized tertiary alkyl halides
Chao Che1, Hanliang Zheng1, Gangguo Zhu1
1Department of Chemistry, Zhejiang Normal University, 688 Yingbin Road, Jinhua 321004, China.
Abstract:
A highly trans-selective Cu-catalyzed carbohalogenation including carbobromination, carboiodination, and carbochlorination of terminal alkynes with activated tertiary alkyl halides has been realized, providing quaternary-carbon-containing alkenyl halides in good yields with excellent regio- and stereoselectivity. Meanwhile, an unprecedented alkyne trans-carboalkynylation process has been achieved via the tandem trans-carbohalogenation/Sonogashira coupling reaction, which furnishes highly functionalized 1,3-enynes in a single chemical transformation.
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