反应详情

温度

90 °C

To a solution of 1,2-difluoro-4-nitrobenzene (3.18 g, 20 mmol) in DMSO (35 mL) were added K2CO3 (6.08 g, 44 mmol) and pyrazole (1.50 g, 22 mmol) with stirring. The reaction mixture was heated at 90° C. for 18 h, and cooled to rt. The mixture was diluted with water (50 mL) and filtered. The filtrate was extracted with DCM (50 mL×3), the combined organic phases were concentrated in vacuo. The crude product was purified by a silica gel column chromatography (PE/CH2Cl2 (V/V)=1:1) to give the title compound as a yellow solid (3.31 g, 80%).

1. temperaturecooled to rt
2. filtrationfiltered
3. extractionThe filtrate was extracted with DCM (50 mL×3)
4. concentrationthe combined organic phases were concentrated in vacuo
5. customThe crude product was purified by a silica gel column chromatography (PE/CH2Cl2 (V/V)=1:1)