反应详情

(ii) n-Propanol (35 ml) and concentrated sulfuric acid (6 drops) were added to a solution of crude 2-(2-fluoro-4-hydroxyphenoxy)propionic acid (8.6 g) in dichloroethane (13 ml). The mixture was heated under reflux with stirring for a period of 6.5 hours, cooled, and the solvent was evaporated under reduced pressure. The residue was treated with water and the aqueous mixture was extracted with dichloromethane. The organic phase was washed with a saturated aqueous solution of sodium hydrogen carbonate and then with water. The organic phase was dried over anhydrous magnesium sulfate, filtered and the solvent was evaporated under reduced pressure to give an oil (5.7 g; 54.8%). The oil was purified by vacuum distillation to give n-propyl 2-(2-fluoro-4-hydroxyphenoxy)propionate (3.7 g; 35.5%); bp 210°-220° C. at 0.1 mm Hg.

1. temperatureThe mixture was heated
2. temperatureunder reflux
3. temperaturecooled
4. customthe solvent was evaporated under reduced pressure
5. additionThe residue was treated with water
6. extractionthe aqueous mixture was extracted with dichloromethane
7. washThe organic phase was washed with a saturated aqueous solution of sodium hydrogen carbonate
8. dry with materialThe organic phase was dried over anhydrous magnesium sulfate
9. filtrationfiltered
10. customthe solvent was evaporated under reduced pressure
11. customto give an oil (5.7 g; 54.8%)
12. distillationThe oil was purified by vacuum distillation