146941-72-2Relevant articles and documents
Oxidative N—N coupling of N-alkyl-3-aminopyrazoles to azopyrazoles in aqueous solutions of NaOCl and NaOBr
Lyalin,Sigacheva,Ugrak,Petrosyan
, p. 164 - 170 (2021)
The influence of the structures of N-alkyl-3-aminopyrazoles on their transformation into azopyrazoles on treatment with sodium hypohalogenites was studied. The reaction of 3-aminopyrazoles unsubstituted at position 4 containing donor substituents with neu
Preparation method of 3-(difluoromethyl)-1-methyl-1H-pyrazole-4-carboxylic acid
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Paragraph 0030-0033; 0037-0039, (2020/07/15)
The invention discloses a preparation method of 3-(difluoromethyl)-1-methyl-1H-pyrazole-4-carboxylic acid, and belongs to the technical field of organic synthesis. The preparation method comprises thefollowing steps: reacting N-methyl-3-aminopyrazole as a raw material with bromine/iodine to replace pyrazole at site 4, then carrying out diazotizing and coupling with potassium difluoromethyl trifluoroborate to obtain 4-bromo-3-(difluoromethyl)-1-methyl-1H-pyrazole, then performing Grignard exchange by adopting isopropyl magnesium chloride and the like, and performing reaction with carbon dioxide to obtain 3-(difluoromethyl)-1-methyl-1H-pyrazole-4-carboxylic acid. The method is simple and convenient to operate, the total yield of the three steps is as high as 64%, the product purity can reach 99.5% or above, the situation in which isomers exist in a traditional process is avoided, and the method has potential process amplification prospects.