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. 71229-85-1, name is 4-Bromo-1-ethyl-1H-pyrazole, A new synthetic method of this compound is introduced below., name: 4-Bromo-1-ethyl-1H-pyrazole
1003281 To a solution of compound 3 (4.3 g, 20.5 mmol) in toluene (50 mL) were added 4- bromo-1-ethyl-1H-pyrazole 4(4.0 g, 22.8 mmol), potassium phosphate (11.0 g, 51.2 mmol), N,N?-dimethylethylenediamine (722 mg, 8.2 mmol) and Cu(I)I (390 mg, 2.0 mmol) at RT underinert atmosphere. The reaction solution was purged with argon for 15 mm and then sealed the tube. The reaction mixture was heated to 140 C and stirred for 16 h. After completion of the reaction by TLC, the reaction mixture was cooed to RT, diluted with EtOAc (50 mL) and filtered. The filtrate was washed with water (40 mL), brine (40 mL), dried over Na2SO4, filtered and concentrated under reduced pressure to obtain the crude. The crude was purified (silica gel chromatography; 9% EtOAc/Hexanes) to afford compound 5 (3.9 g, 63%) as a pale brown solid. 1H NMR (400 MHz, CDC13): 7.64 (s, 1H), 7.60 (s, 1H), 7.16 (d, I = 8.4 Hz, 1H), 7.01 (dd, J =8.4, 6.4 Hz, 1H), 6.12 (s, 1H), 4.25 (q, J = 7.2 Hz, 2H), 1.69-1.62 (m, 1H), 1.56 (t, J = 7.2 Hz, 3H), 0.92-0.87 (m, 2H), 0.76-0.72 (m, 2H); LC-MS (ES): 98.6%; m/z 304.3 (M + Hj; (column: X Select C-18, 50 x 3.0 mm, 3.5 tm); RT 4.23 mill; 5 mM NH4OAc: ACN; 0.8 mL/min).
The synthetic route of 71229-85-1 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; PHARMAKEA, INC.; BAIN, Gretchen; EVANS, Jillian Frances; HUTCHINSON, John Howard; LONERGAN, David; (123 pag.)WO2016/191427; (2016); A1;,
Pyrazole – Wikipedia,
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