Merging Hydrogen Atom Transfer and Halogen Atom Transfer for Iodide-Catalyzed Radical Reductive Cyclization of
Linglong Ding1, Yi-Hui Deng2, Tian-Yu Sun3
1Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi, Jiangsu 214122, China.
Abstract:
Described herein is the development of a metal-free iodide-catalyzed radical reductive cyclization of 1,6-enynes. A strategy involving in situ iodination/radical cyclization/silyl radical-mediated halogen atom transfer/hydrogen atom transfer for the synthesis of functionalized pyrrolidines has been proposed. Using this halogen-atom abstraction protocol, 1,6-enynes with various vinyl halides including inert fluorides, chlorides, and reactive bromides could be transformed into substituted pyrroles via a multistep radical isomerization process.
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