Copper‐Catalyzed Remote C(sp3)−H Trifluoromethylation of Carboxamides and Sulfonamides. Issue 8 (21st January 2019)

• Record Type: Journal Article
• Authors: Liu, Zhonglin; Xiao, Haiwen; Zhang, Benxiang; Shen, Haigen; Zhu, Lin; Li, Chaozhong
• Is Part Of: Angewandte Chemie international edition. Volume 58:Issue 8(2019)
• Page Start: 2510
• Page End: 2513
• Publication Date: 2019-01-21
• Subjects: copper -- radicals -- reaction mechanisms -- synthetic methods -- trifluoromethylation; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201813425
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Reported herein is an unprecedented protocol for trifluoromethylation of unactivated aliphatic C(sp 3 )−H bonds. With Cu(OTf)2 as the catalyst, the reaction of N‐fluoro‐substituted carboxamides (or sulfonamides) with Zn(CF3 )2 complexes provides the corresponding δ‐trifluoromethylated carboxamides (or sulfonamides) in satisfactory yields under mild reaction conditions. A radical mechanism involving 1, 5‐hydrogen atom transfer of N‐radicals followed by CF3 ‐transfer from Cu II −CF3 complexes to the thus formed alkyl radicals is proposed. Abstract : From a distance : Chemoselective trifluoromethylation of unactivated C(sp 3 )−H bonds distal to the functional group was achieved under mild, copper‐catalyzed conditions. A radical mechanism involving 1, 5‐hydrogen atom transfer of N‐radicals followed by CF3 ‐transfer from Cu II −CF3 complexes to the thus formed alkyl radicals is proposed.