Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 1353100-91-0, name is Ethyl 3-bromo-1H-pyrazole-4-carboxylate, A new synthetic method of this compound is introduced below., Product Details of 1353100-91-0
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).
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.