4-bromo-1-(4-chlorophenyl)-1H-pyrazole synthesis
- Product Name:4-bromo-1-(4-chlorophenyl)-1H-pyrazole
- CAS Number:885017-82-3
- Molecular formula:C9H6BrClN2
- Molecular Weight:257.51
Yield:885017-82-3 800 mg
Reaction Conditions:
with pyridine;copper(II) sulphate in dichloromethane at 20;
Steps:
67.1
To a solution of 4-brompyrazole (500 mg, 3.40 mmol) in DCM (10 mL) at rt was added 4-chlorophenylboronic acid (1.06 g, 6.80 mmol) , Cu(OAc)2 (1.24 g, 6.80 mmol) and pyridine (806 mg, 10.20 mmol). The reaction was stirred at rt overnight. After the reaction was completed as indicated by TLC analysis, the suspension was filtered through a pad of Celite. The filtrate was quenched with brine (10 mL) and extracted with DCM (10 mL x 3). The combined organic phase was washed with brine, dried with anhydrous Na2SO4, filtered and concentrated in vacuo. The residue was purified by silica-gel column chromatography (PE : EtOAc=100:1 to 50:1) to give 800 mg of the title compound as white solid. 1H NMR (300 MHz, CDCl3) δ 7.91 (s, 1H), 7.67 (s, 1H), 7.59 (d, J = 8.9 Hz, 2H), 7.43 (d, J = 8.9 Hz, 2H).
References:
WO2022/36188,2022,A1 Location in patent:Paragraph 0931-0933
