A common heterocyclic compound, 176969-34-9, name is 3-(Difluoromethyl)-1-methyl-1H-pyrazole-4-carboxylic acid, molecular formula is C6H6F2N2O2, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. 176969-34-9.
3-(difluoromethyl)-1 -methyl-i H-pyrazole-4-car-boxylic acid (2 g, 11.36 mmol) was dissolved in 20 mL sulthryl dichloride, and then heated to reflux for 3 h, the excessive sulfuryl dichloride was evaporated under reduced pressure to get 3-(difluoromethyl)-i -methyl- iH-pyrazole-4- carbonyl chloride, and then the carbonyl chloride was dissolved in 30 mL dichloromethane for the following reaction. To a cooled solution of (3-aminophenyl)methanol (1.4 g, 11.36 mmol) dissolved in 20 mL dichloromethane and 5 mL triethylamine was added slowly the solution of the carbonyl chloride at 0-5 C. Afier the reaction was stirred for 6 h at room temperature, analysis by Thin-Layer Chromatography showed complete conversion to product, the excessive solvent was evaporated under reduced pressure. the residual was purified by column chromatography on silica gel (eluent: ethyl acetate:petroleum ether=i:3; silica gel: 100-140 mesh, Qingdao Marine Chemical Co., Ltd.) to obtain 3-(di- fluoromethyl)-N-(3-(hydroxymethyl)phenyl)- i-methyl-i Hpyrazole-4-carboxamide (2.32 g) as white solid with yield of 73%. ?H NMR (300 MHz, CDC13) oe (ppm): 4.11 (s, 3H),4.73 (s, 2H), 7.16-7.81 (m, 6H).
The synthetic route of 3-(Difluoromethyl)-1-methyl-1H-pyrazole-4-carboxylic acid has been constantly updated, and we look forward to future research findings.