反应详情

温度

100 °C

Triethylamine (40 ml) was gradually dropwise added to a toluene solution (10 liters) containing 2-fluoro-4-chloro-5-cyclopentyloxyphenylisocyanate (4.0 kg, 15.6 mol) and methyl 2-hydroxy-3-methyl-3-butenoate (2.4 kg, purity about 90 %, 18.4 mol), as put in a 20-liter stainless steel vessel, with cooling in an ice-water bath, in such a way that the temperature of the reaction solution did not rise. The whole was stirred for 2 hours at the determined temperature until the starting materials disappeared by TLC. Next, after addition of potassium carbonate (200 g, 1.45 mol), the reaction mixture was heated in a water bath (100° C.) for 4 hours with stirring with removing the methanol formed therefrom through a distillation device equipped to the reactor. After reaction, the reaction mixture was washed with 1 N hydrochloric acid (10 liters) and 1 N sodium hydroxide (10 liters) and further with 1 N hydrochloric acid (10 liters). The toluene layer was dried over anhydrous magnesium sulfate, the solvent was removed by distillation under reduced pressure, and hexane of about a half of the oily product formed was added to the oily product formed. This was then allowed to stand at room temperature for a while. A whitish yellow solid precipitated out, which was taken out by filtration and well dried to obtain 3N-(2-fluoro-4-chloro-5-cyclopentyloxyphenyl)-5-isopropylidene-1,3-oxazolidine-2, 4-dione (4.19 kg, 11.8 mol). Yield: 75.7 %. Spectral data and other data of the product are those as shown in Example 27.

1. customas put in a 20-liter stainless steel vessel
2. temperaturewith cooling in an ice-water bath
3. stirringwith stirring
4. customwith removing the methanol
5. customformed
6. customthrough a distillation device equipped to the reactor
7. customAfter reaction
8. washthe reaction mixture was washed with 1 N hydrochloric acid (10 liters) and 1 N sodium hydroxide (10 liters) and further with 1 N hydrochloric acid (10 liters)
9. dry with materialThe toluene layer was dried over anhydrous magnesium sulfate
10. customthe solvent was removed by distillation under reduced pressure, and hexane of about a half of the oily product
11. customformed
12. additionwas added to the oily product
13. customformed
14. customto stand at room temperature for a while
15. customA whitish yellow solid precipitated out
16. filtrationwhich was taken out by filtration
17. customwell dried