反应详情

Potassium tert-butoxide (5.16 g., 0.046 mole) was dissolved in 60 ml. of tert-butanol. Dimethyl carbonate (4.14 g., 0.046 mole) and then 2-(2,6-dichlorophenyl)-2-hydroxyacetamide (5 g., 0.023 mole) were added. The suspension was heated at reflux for 2 hours and cooled to room temperature. Hydrochloric acid (46 ml. of 1N) and then 100 ml. of water were added, and the mixture extracted with three portions of methylene chloride. The combined organic extracts were washed with brine, dried over anhydrous magnesium sulfate, filtered and concentrated to dryness. Recrystallization of the residue from toluene gave purified 5-(2,6-dichlorophenyl)oxazolidine-2,4-dione (3.15 g., 50 %; m.p. 151°-153° C.), ir (KBr) 1818, 1739, 1724, 1434, 1377 cm-1.

1. temperatureThe suspension was heated
2. temperatureat reflux for 2 hours
3. extractionthe mixture extracted with three portions of methylene chloride
4. washThe combined organic extracts were washed with brine
5. dry with materialdried over anhydrous magnesium sulfate
6. filtrationfiltered
7. concentrationconcentrated to dryness
8. customRecrystallization of the residue from toluene
9. customgave
10. custompurified 5-(2,6-dichlorophenyl)oxazolidine-2,4-dione (3.15 g., 50 %; m.p. 151°-153° C.), ir (KBr) 1818, 1739, 1724, 1434, 1377 cm-1