CF2Br2 as a Source for Difluoroolefination of 1,3-Enynes via N-Heterocyclic Carbene Catalysis
Lei Chen1, Jingyi Wang1, Chen Lin1
1State Key Laboratory of Natural Medicines, School of Science, China Pharmaceutical University, Nanjing, 210009, P.R. China.
Abstract:
Commercially available CF2Br2 has been used as a convenient source for the rapid and reliable incorporation of the gem-difluorovinyl motif into an allene framework via an N-heterocyclic carbene catalyzed difluoroolefination of 1,3-enynes. The reaction proceeds through a cascade three-component radical relay/elimination process. This protocol is distinguished by its mild conditions, readily accessible starting materials, wide substrate scope, and ease of late-stage functionalization, thus unlocking an untraditional strategy to construct a new class of functionalized gem-difluorovinyl allenes.
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