Norman, Natalie J.; Bao, Si Tong; Curts, Lynne; Hui, Tiffani; Zheng, Shao-Liang; Shou, Tiffany; Zeghibe, Ana; Burdick, Izzy; Fuehrer, Hannah; Huang, Adrian published the artcile< Highly Selective N-Alkylation of Pyrazoles: Crystal Structure Evidence for Attractive Interactions>, Application of C9H7BrN2, the main research area is alkyl pyrazole preparation regioselective crystal structure; pyrazole electrophile Michael reaction.
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.
Journal of Organic Chemistry published new progress about Bond angle. 13808-65-6 belongs to class pyrazoles-derivatives, and the molecular formula is C9H7BrN2, Application of C9H7BrN2.
Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics