Electric Literature of 2075-45-8, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 2075-45-8, name is 4-Bromo-1H-pyrazole belongs to pyrazoles-derivatives compound, it is a common compound, a new synthetic route is introduced below.
To a solution of 4-bromopyrazole (4.00 g, 27.2 mmol) in anhydrous THF(25 mL) cooled to 0 C was added NaH (60% dispersion in mineral oil, 1.63 g, 40.8 mmol) in four equivalent portions. The contents were stirred at 0 C for 30 minutes, and then 2- (trimethylsilyl)ethoxymethyl chloride (5.06 mL, 28.6 mmol) was added slowly. The reaction was stirred at room temperature for 16 hours, diluted with diethyl ether (200 mL), and washed with brine (100 mL). The organic phase was dried over anhydrous Na^SCL and concentrated under reduced pressure to afford 22 as a clear oil (7.50 g, 99% yield).1H NMR (400 MHz, CDCI3) delta 7.59 (s, 1H), 7.49 (s, 1H), 5.38 (s, 2H), 3.55 (t, J= 8.1 Hz, 2H), 0.90 (t, J= 8.5 Hz, 2H), -0.02 (s, 9H).13C NMR (101 MHz, CDCI3) delta 140.5, 129.6, 94.8, 80.8, 67.1, 17.9, -1.3.
The synthetic route of 4-Bromo-1H-pyrazole has been constantly updated, and we look forward to future research findings.
Reference:
Patent; YALE UNIVERSITY; JORGENSEN, William L.; TRIVEDI-PARMAR, Vinay; (142 pag.)WO2019/178480; (2019); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics