反应详情

To a suspension of Na2CO3 (3.6 g, 33.9 mmol) in CH2Cl2 (30 mL) was added 1-tert-butyl-1H-pyrazole (2.1 g, 17 mmol) and Br2 (0.9 mL). The mixture was stirred at room temperature overnight. The formed solid was removed by filtration and the filter cake was washed with CH2Cl2 (30 mL). The filtrates were washed with water (20 mL) and brine (20 mL), dried (MgSO4), and concentrated under reduced pressure to afford crude 4-bromo-1-tert-butyl-1H-pyrazole (2.9 g, 85%), which was used in next step without further purification. MS (ESI) m/z: 203 [M+H]+.

1. customThe formed solid was removed by filtration
2. washthe filter cake was washed with CH2Cl2 (30 mL)
3. washThe filtrates were washed with water (20 mL) and brine (20 mL)
4. dry with materialdried (MgSO4)
5. concentrationconcentrated under reduced pressure