Norman, Natalie J.; Bao, Si Tong; Curts, Lynne; Hui, Tiffani; Zheng, Shao-Liang; Shou, Tiffany; Zeghibe, Ana; Burdick, Izzy; Fuehrer, Hannah; Huang, Adrian published an article in 2022. The article was titled 《Highly Selective N-Alkylation of Pyrazoles: Crystal Structure Evidence for Attractive Interactions》, and you may find the article in Journal of Organic Chemistry.SDS of cas: 20154-03-4 The information in the text is summarized as follows:
Inspired by crystal structures, authors designed and achieved a catalyst-free Michael reaction for the preparation of an N1-alkyl pyrazoles I (R1 = 3-CF3, 3-COOEt, 3-NO2-4-Br, etc.; R2 = CN, COOEt) in a high yield (>90%) with excellent regioselectivity (N1/N2 > 99.9:1). The scope of this protocol has been extended to accomplish the first general regioselective N1-alkylation of 1H-pyrazoles to give di-, tri-, and tetra-substituted pyrazoles in a single step. The resulting pyrazoles bear versatile functional groups such as bromo, ester, nitro, and nitrile, offering opportunities for late-stage functionalization. This efficient methodol. will have an impact on drug discovery, as several Food and Drug Administration-approved drugs are pyrazole derivatives A working hypothesis for the regioselectivity is proposed. X-ray crystal structures of the products that highlight the attractive interactions are discussed. This report provides a rare source for the further elucidation of the attractive interactions because the isomeric ratios and the crystal structures are directly related. In the experiment, the researchers used many compounds, for example, 3-(Trifluoromethyl)-1H-pyrazole(cas: 20154-03-4SDS of cas: 20154-03-4)
3-(Trifluoromethyl)-1H-pyrazole(cas: 20154-03-4) belongs to pyrazoles. The application of pyrazole derivatives in the development of anticancer agents has been thoroughly investigated and verified. Moreover, the medicinal features of a number of natural products incorporating pyrazole moiety such as pyrazofurin, pyrazofurin B, pyrazole-3(5)-carboxylic acid and 4-methylpyrazole-3(5)-carboxylic acid have been reported.SDS of cas: 20154-03-4
Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics