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 139308-52-4 as follows. Safety of Ethyl 3-bromo-1-methyl-1H-pyrazole-4-carboxylate
[1042] a mixture of compound 163c (2 g, 8.58 mmol), meb(oh)2 (2.05 g, 34.3 mmol), pd(pph3)4 (793 mg, 687 umol), K2CO3 (2.37 g, 17.2 mmol) in dioxane (50 ml) and H2O (10 ml) was degassed and purged with n2 for 3 times, and then the mixture was stirred at 120 C for 12 hour under N2 atmosphere. The reaction mixture was extracted with ethyl acetate 50 ml (50 ml x 2). The combined organic layers were dried over Na2SO4, filtered and concentrated under reduced pressure to give a residue. The residue was purified by column chromatography (SiO2, petroleum ether: ethyl acetate = 100: 1 to 80: 1). Compound 408a (1.4 g, yield: 97.0%) was obtained as a yellow solid. 1H NMR (400mhz, CDCl3) delta 7.87 – 7.73 (m, 1h), 4.27 (q, j = 7.1 hz, 2h), 3.91 -3.75 (m, 3h), 2.51 – 2.40 (m, 3h), 1.33 (t, j = 7.1 hz, 3h).
According to the analysis of related databases, 139308-52-4, the application of this compound in the production field has become more and more popular.
Reference:
Patent; BLADE THERAPEUTICS, INC.; BUCKMAN, Brad, Owen; YUAN, Shendong; ADLER, Marc; EMAYAN, Kumaraswamy; MA, Jingyuang; (687 pag.)WO2018/64119; (2018); A1;,
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