反应详情

Cesium carbonate (108 g, 0.33 mol) was added in one portion to a stirred solution of 3,5-dichlorophenol (49 g, 0.30 mol) in acetone (900 ml) at room temperature under nitrogen. To this suspension a solution of 1-bromo-2-butanone (30.6 ml, 0.30 mol) in acetone (300 ml) was added dropwise and the resultant suspension was heated under reflux for 2 hours. The suspension was cooled to room temperature, water (200 ml) was added and the acetone was removed under reduced pressure. The mixture was extracted with dichloromethane (2×300 ml) and the combined organic phases were dried over magnesium sulphate, filtered and concentrated under reduced pressure to leave a clear oil. The crude product was purified by flash column chromatography on silica gel eluting with dichloromethane:cyclohexane (50:50, by volume) to provide the title compound (65 g) as a yellow oil.

1. temperatureunder reflux for 2 hours
2. customthe acetone was removed under reduced pressure
3. extractionThe mixture was extracted with dichloromethane (2×300 ml)
4. dry with materialthe combined organic phases were dried over magnesium sulphate
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure
7. customto leave a clear oil
8. customThe crude product was purified by flash column chromatography on silica gel eluting with dichloromethane:cyclohexane (50:50, by volume)