反应详情

温度

0 °C

A mixture of 2-bromo-5-fluoroaniline (5 g) in ethanol (17.5 ml) and 1.6M HCl (50 mL) at −5° C. was treated with 2.5M NaNO2 (10.5 ml). 4.5M potassium acetate (29.2 ml) was then added, followed by ethyl 2-oxocyclopentanecarboxylate (3.8 ml). The reaction mixture was stirred at 0° C. for 15 minutes, warmed to 20° C. over 1.5 hours, extracted with dichloromethane, concentrated and dried in vacuo. The residue was dissolved in 67 ml of (H2SO4/ethanol, 17:50), refluxed for 2 days, cooled to room temperature, quenched with water and extracted with dichloromethane. The combined extracts were washed with brine, dried (MgSO4), filtered and concentrated. The concentrate was purified by column chromatography on silica gel with 5-20% ethyl acetate in hexanes. The product was purified further by trituration with ethanol.

1. temperaturewarmed to 20° C. over 1.5 hours
2. extractionextracted with dichloromethane
3. concentrationconcentrated
4. customdried in vacuo
5. dissolutionThe residue was dissolved in 67 ml of (H2SO4/ethanol, 17:50)
6. temperaturerefluxed for 2 days
7. temperaturecooled to room temperature
8. customquenched with water
9. extractionextracted with dichloromethane
10. washThe combined extracts were washed with brine
11. dry with materialdried (MgSO4)
12. filtrationfiltered
13. concentrationconcentrated
14. customThe concentrate was purified by column chromatography on silica gel with 5-20% ethyl acetate in hexanes
15. customThe product was purified further by trituration with ethanol