Synthetic Route of 1353100-91-0,Some common heterocyclic compound, 1353100-91-0, name is Ethyl 3-bromo-1H-pyrazole-4-carboxylate, molecular formula is C6H7BrN2O2, 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.
To a solution of NaH (275 mg, 6.86 mmol, 60% purity) in THF (5 mL) was added dropwise a solution of ethyl 3-bromo-lH-pyrazole-4-carboxylate (1.0 g, 4.57 mmol) in THF (10 mL) at 0 C. After addition, the mixture was stirred at this temperature for lh, and then Mel (2.93 g, 20.64 mmol, 1.29 mL) was added dropwise at 0 C. The resulting mixture was stirred at 25 C for 19h. The reaction mixture was quenched by addition sat. H4CI (5 mL), and then diluted with H20 (10 mL) and extracted with EtOAc (20 mL x 2). The combined organic layers were washed with brine (15 mL x 2), dried over Na2S04, filtered and concentrated under reduced pressure to give a residue. The residue was purified by column chromatography (Si02, Petroleum ether/Ethyl acetate = 8/1 to 5: 1) to give the Compound 142A (120 mg, yield: 11.27%) was obtained as a yellow oil and Compound 142B (370.00 mg, yield: 34.74%) was obtained as a white solid. (1387) [0574] 1H NMR (400MHz, CDC13) (142A) delta 7.93 (s, 1H), 4.42 – 4.21 (m, 2H), 3.97 – 3.82 (m, 3H), 1.36 (t, J = 7.2 Hz, 3H) (1388) [0575] 1H NMR (400MHz, CDC13) (142B) delta 7.83 (s, 1H), 4.30 (q, J = 7.0 Hz, 2H), 3.94 – 3.86 (m, 3H), 1.41 – 1.28 (m, 3H).
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route Ethyl 3-bromo-1H-pyrazole-4-carboxylate, its application will become more common.
Reference:
Patent; BLADE THERAPEUTICS, INC.; BUCKMAN, Brad, Owen; YUAN, Shendong; MA, Jingyuan; EMAYAN, Kumaraswamy; ADLER, Marc; (327 pag.)WO2018/9417; (2018); A1;,
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