反应详情

温度

100 °C

A mixture of 4-[N-methyl-N-(6-bromo-2-benzoxazolyl)amino]phenol (0.6, 0.002 mole), ethyl 2-bromopropionate (0.4 g, 0.002 mole), anhydrous potassium carbonate (0.3 g, 0.002 mole) and methyl ethyl ketone (6 ml) was heated under reflux, with stirring, for a period of 3 hours. Thin layer chromatography indicated that the reaction had not gone to completion and therefore further anhydrous potassium carbonate (0.15 g) and methyl ethyl ketone was added and the mixture was heated under reflux for a further period of 3 hours. The solvent was removed by distillation under reduced pressure, water (50 ml) was added to the residue and the aqueous mixture was extracted with diethyl ether (3×30 ml). The combined extracts were washed with brine, dried over anhydrous magnesium sulfate and the solvent was evaporated to give a dark red oil. The oil was heated at a temperature of 100° C. at a pressure of 0.1 mm Hg for a period of 2 hours to remove residual ethyl 2-bromopropionate and the residue was recrystallised from hexane/cyclohexane to give the title compound as a white solid (0.45 g), mp 91°-92° C.

1. temperaturewas heated
2. temperatureunder reflux
3. temperaturethe mixture was heated
4. temperatureunder reflux for a further period of 3 hours
5. customThe solvent was removed by distillation under reduced pressure, water (50 ml)
6. additionwas added to the residue
7. extractionthe aqueous mixture was extracted with diethyl ether (3×30 ml)
8. washThe combined extracts were washed with brine
9. dry with materialdried over anhydrous magnesium sulfate
10. customthe solvent was evaporated
11. customto give a dark red oil
12. customto remove residual ethyl 2-bromopropionate
13. customthe residue was recrystallised from hexane/cyclohexane