Electric Literature of 1453-58-3, 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 1453-58-3 as follows.
Preparation of tert-butyl 3-(bromomethyl)-1H-pyrazole-1-carboxylate After 3-methyl-1-pyrazole (2.0 g, 24.3 mmol) was dissolved in acetonitrile (25 mL), tert-butyl dicarbonate (6.5 g, 29.8 mmol) and 4-dimethylaminopyridine (0.31 g, 2.49 mmol) were added thereto at 0° C., and the mixture was slowly warmed to room temperature and then stirred for 2 hours. Ethyl acetate (50 mL) was added to the reaction material, and the result was washed with a 1N aqueous hydrochloric acid solution (50 mL), a saturated aqueous sodium hydrogen carbonate solution (50 mL) and salted water (50 mL), dried with anhydrous magnesium sulfate, and then concentrated under reduced pressure. The residue was purified using silica gel column chromatography (ethyl acetate/normal-hexane=1/4) to give tert-butyl 3-methyl-1H-pyrazole-1-carboxylate (4.13 g, 93percent). 1H-NMR (300 MHz, CDCl3) delta 1.64 (s, 9H), 2.34 (s, 3H), 6.17 (s, 1H), 7.96 (s, 1H).
According to the analysis of related databases, 1453-58-3, the application of this compound in the production field has become more and more popular.
Reference:
Patent; KOREA RESEARCH INSTITUTE OF CHEMICAL TECHNOLOGY; SON, Jong Chan; KIM, Bong Jin; KIM, Jae Hak; LEE, Ill Young; YUN, Chang Soo; LEE, Sang Ho; LEE, Chong Kgo; US2014/249162; (2014); A1;,
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