反应详情

To a solution of N,N-dimethylacetamide (1.66 g, 19.1 mmol) in dichloroethane (50 mL) at -15° C., was added trifluoromethanesulfonic anhydride (5.39 g, 19.1 mmol) dropwise and the mixture was stirred for 5 min. A mixture of 3-(4-fluorophenoxy)styrene (4.08 g, 19.1 mmol) and collidine (2.31 g, 19.1 mmol) as a solution in dichloroethane (10 mL) was then added dropwise. Upon completion of addition, the cooling bath was withdrawn and the reaction allowed to warm to ambient temperature, then further brought to reflux for 18 hours. Water (20 mL) was then added and the reaction was kept at reflux for an additional 5 hours. It was then cooled to ambient temperature and the layers were separated. The organic phase was washed with 10% aqueous HCl (50 mL) and water (50 mL). It was then dried over MgSO4 and concentrated. The resulting residue was chromatographed (silica gel; hexanes, ether 90:10) to afford 2.60 g (53%) of 3-(3-(4-fluorophenoxy)phenyl)cyclobutanone as a colorless oil.

1. additionwas then added dropwise
2. additionUpon completion of addition
3. customthe cooling bath was withdrawn
4. temperatureto reflux for 18 hours
5. additionWater (20 mL) was then added
6. temperatureat reflux for an additional 5 hours
7. temperatureIt was then cooled to ambient temperature
8. customthe layers were separated
9. washThe organic phase was washed with 10% aqueous HCl (50 mL) and water (50 mL)
10. dry with materialIt was then dried over MgSO4
11. concentrationconcentrated
12. customThe resulting residue was chromatographed (silica gel; hexanes, ether 90:10)