In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 930-36-9 as follows. Application In Synthesis of 1-Methylpyrazole
To a stirred solution of 1-methyl-1H-pyrazole (609 mmol) in dry ether (600 mL) under an atmosphere of nitrogen was added a solution of n-BuLi in hexane (2.6M, 670 mmol) dropwise at -78oC over a period of 1 h. The reaction mixture was stirred at this temperature for a further 1 hour, and then dry carbon dioxide gas was passed through the mixture at -78oC for 30 min. The reaction mixture was then allowed to warm to room temperature and quenched with water (500 mL). The aqueous phase was separated, washed with ether (500 mL) and cooled to 2-3oC. To the stirred mixture was added concentrated aqueous hydrochloric acid until a pH of 3 was obtained. The resulting precipitate was collected by filtration, washed with ice-cold water (20 mL), dried first in open air, and then in a vacuum desiccator over phosphorus pentoxide to afford 2-methyl-2H-pyrazole-3-carboxylic acid as a white powder. Compound wt: 35.3 g, 45.4% yield. 1H NMR (400 MHz, DMSO-d6) delta: 13.31(1H, bs); 7.50 (1H, d); 6.81 (1H, d); 4.07 (3H, s).
According to the analysis of related databases, 930-36-9, the application of this compound in the production field has become more and more popular.
Reference:
Patent; Dykes, Graeme James; Fletcher, Stephen Robert; Menet, Christel Jeanne Marie; Merayo, Nuria Merayo; Schmitt, Benoit Antoine; US2008/242661; (2008); A1;,
Pyrazole – Wikipedia,
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