Application of 70951-85-8, 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. 70951-85-8, name is 4-Bromo-1-(tert-butyl)-1H-pyrazole belongs to pyrazoles-derivatives compound, it is a common compound, a new synthetic route is introduced below.
To a -78 0C solution of 4-bromo-l -7-butyI-lH-pyrazole (15 g, 74.3 mmol) in anhydrous THF (100 mL) was added /7-BuLi (2.5 M in hexane, 53 mL, 132 mmol) under N2, and the resulting mixture was stirred at -78C for 30 min. Excess dry ice was added at -78 0C, and the mixture was warmed slowly to RT and stirred overnight. The reaction was concentrated in vacuo, water was added and the pH was adjusted to pH 3 by the addition of 2N aq HCI. The aqueous solution was extracted with EtOAc. The extracts were washed with brine, dried (MgSO4) and concentrated in vacuo. The residue was recrystallized (EtO Ac-pet, ether) to give 1 -/-butyl- lH-pyrazole-4-carboxylic acid (8.0 g, 67 % yield). 1H NMR (300 MHz, CDCl3): ^ 8.10 (s, 1 H), 8.03 (s, 1 H), 1.64 (s, 9 H); MS (ESI) m/z: 168.9 [M+Hf.
The synthetic route of 4-Bromo-1-(tert-butyl)-1H-pyrazole has been constantly updated, and we look forward to future research findings.