Strategy To Prepare 3-Bromo- and 3-Chloropyrazoles
作者:Richard J. Fox、Michael A. Schmidt、Martin D. Eastgate
DOI:10.1021/acs.joc.7b03282
日期:2018.3.2
A general strategy to prepare substituted 3-bromo- and 3-chloropyrazoles is described. The three-step method involves condensation of crotonates or β-chloro carboxylic acids with hydrazines, followed by halogenation and oxidation. Several condensation and oxidation protocols were developed to enable preparation of a wide variety of 3-halopyrazoles with good to excellent yields and regiocontrol.
Gaede, Bruce J.; McDermott, Lisa L., Journal of Heterocyclic Chemistry, 1993, vol. 30, # 1, p. 49 - 54
作者:Gaede, Bruce J.、McDermott, Lisa L.
DOI:——
日期:——
New regional isomers of 1-methyl-5-(trifluoromethyl)pyrazoles
作者:John P. Chupp
DOI:10.1002/jhet.5570310613
日期:1994.11
reported compound, 1-methyl-5-(trifluoromethyl)-2,3,4,5-tetrahydropyrazol-3-one, 4, a series of regionalisomers of 1-methyl-5-(trifluoromethyl)-3-chloropyrazole, newly substituted in the 4-position were prepared by original syntheses. Chief among them was the newregional 4-hydroxy isomer, 3a, a linkage reagent valuable for preparing new SAR candidates in the bio-active pyrazole phenyl ether series