An N‐Trifluoromethylation/Cyclization Strategy for Accessing Diverse N‐Trifluoromethyl Azoles from Nitriles and 1, 3‐Dipoles. (23rd November 2021)

• Record Type: Journal Article
• Authors: Zhang, Ru Zhong; Zhang, Ru Xue; Wang, Shuang; Xu, Cong; Guan, Wei; Wang, Mang
• Is Part Of: Angewandte Chemie. Volume 134:Number 1(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-11-23
• Subjects: 1, 3-dipoles -- cyclizations -- heterocycles -- nitriles -- synthetic methods; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202110749
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: N‐Trifluoromethyl azoles are valuable targets in medicinal chemistry, but their synthesis is challenging. Classical preparation of N‐CF3 azoles relies on the functional group interconversions but suffers from tedious N‐pre‐functionalization and unfriendly agents. Introduction of the CF3 onto the nitrogen of heterocycles provides a direct route to such motifs, but the N‐trifluoromethylation remains underdeveloped. Reported here is an alternative and scalable cyclization strategy based on NCF3 ‐containing synthons for constructing N‐CF3 azoles. The approach involves the N‐trifluoromethylation of nitriles followed by a [3+2] cyclization between resulting N‐CF3 nitrilium derivatives and 1, 3‐dipoles. PhICF3 Cl was an effective CF3 source for the transformation. As a result, a generic platform is established to divergently synthesize N‐trifluoromethylated tetrazoles, imidazoles, and 1, 2, 3‐triazoles by using sodium azide, activated methylene isocyanides, and diazo compounds as dipoles. Abstract : A scalable N ‐trifluoromethylative cyclization strategy is reported to construct N ‐CF3 tetrazoles/imidazoles/1, 2, 3‐triazoles. N ‐CF3 nitrilium derivatives are obtained via the N ‐trifluoromethylation of nitriles and well used as NCF3 ‐containing synthons in 1, 3‐dipolar cyclizations for the first time. A generic platform for accessing diverse N ‐CF3 azoles is thus provided.