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., category: pyrazoles-derivatives
Step 1: Synthesis of 6-chloro-1-(1-ethyl-1H-pyrazol-4-yl)-7-fluoro-1H-indole (9):1003491 To a stirred solution of 6-chloro-7-fluoro-1H-indole 8 (400 mg, 2.36 mmol) in toluene(10 mL) were added 4-bromo-1-ethyl-1H-pyrazole 4 (Step 3 above; 414 mg, 2.36 mmol),potassium phosphate (1.25 g, 5.91 mmol), N,N?-dimethylethylenediamine (84 mg, 0.95 mmol)and Cu(I)I (45 mg, 0.24 mmol) at RT under inert atmosphere. The resulted solution was purged with argon and sealed the tube. The reaction mixture was then heated to 140 C for 16 h. After completion of the reaction (monitored by TLC), the reaction mixture was cooled to RT, diluted with hexane (10 mL) and filtered through a short pad of celite. The filtrate was washed with water (2x 10 mL), dried over Na2SO4, filtered and concentrated under reduced pressure to obtain the crude. The crude was purified (silica gel chromatography; 8-10% EtOAc/Hexanes) to afford compound 9 (224 mg, 36%) as a light brown thick liquid. 1H NMR (500 MHz, CDC13): oe 7.64 (s, 1H), 7.61 (s, 1H), 7.31 (d, J = 8.0 Hz, 1H), 7.12-7.07 (m, 2H), 6.60-6.59 (m, 1H), 4.22 (q, J = 7.5 Hz, 2H), 1.55 (t, J = 7.5 Hz, 3H); LC-MS (ES): 94.7%; mlz 264.1 (M + Hj; (column: X Select C-18, 50 x 3.0 mm, 3.5 jim); RT 3.87 mm; 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.; HUTCHINSON, John, Edward; LONERGAN, David; WO2015/77503; (2015); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics