General Access to N−CF3 Secondary Amines and Their Transformation to N−CF3 Sulfonamides. (9th November 2022)

• Record Type: Journal Article
• Authors: Wang, Leibing; Wang, Jieping; Ye, Sitao; Jiang, Beihan; Guo, Zihao; Mumtaz, Yasir; Yi, Wenbin
• Is Part Of: Angewandte Chemie. Volume 134:Number 49(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-11-09
• Subjects: Amines -- Hydrogen Fluoride -- Isothiocyanates -- Sulfonamides -- Trifluoromethylation; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202212115
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: The synthesis of N −CF3 compounds through fluorination or trifluoromethylation of N ‐containing compounds has been extensively investigated. However, general access to N −CF3 compounds simply from N −CF3 secondary amines is hampered by the challenging preparation and instability of these amines, as well as a much lower reactivity due to the strong electron‐withdrawing nature and steric bulk of the trifluoromethyl moiety. Herein, we report a general and highly efficient synthesis of N −CF3 secondary amines with excellent isolated yields via the addition of the in situ generated difluoromethyl imine (R−N=CF2 ) intermediates with hydrogen fluoride, which is mildly produced by triethylsilane and silver fluoride. N −CF3 sulfonamides, highly desirable but scarce at present, are easily accessible from these valuable building blocks through an unprecedented route. This study will bring new vitality to the synthesis of N −CF3 compounds. Abstract : A new and mild method for the generation of HF from triethylsilane and silver fluoride leads to a highly efficient one‐pot synthesis of N −CF3 secondary amines. Novel N −CF3 sulfonamides were constructed from these promising amine building blocks and sulfonyl bromides in an unprecedented route.