Catalyst-Free Regio- and Stereoselective C(sp2)-H Chlorination of Enamides at Room Temperature
Meng-Liang Deng1, Meng-Wei Sheng1, Xu-Kang Wen1
1College of Advanced Interdisciplinary Science and Technology, Henan University of Technology, Zhengzhou 450001, China.
Abstract:
We disclose herein a catalyst-free, room-temperature protocol for the highly regio- and stereoselective alkenyl C(sp2)-H chlorination of diverse enamides with commercially available, inexpensive N-chlorosuccinimide (NCS) as the electrophilic chlorinating reagent under exceedingly mild conditions. This operationally simple approach features a remarkably broad substrate scope and accommodates excellent functional group tolerance, affording a diverse range of synthetically valuable geometrically defined β-chlorinated enamides in high yields with an exclusive E configuration.
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