反应详情

Phosphoryl chloride (55 ml) is carefully added to barbituric acid (10 g, 78.1 mmol) at 0° C. Water (1.7 ml) is then added dropwise such that the temperature does not exceed 5° C. The mixture is boiled under reflux for 5 h and, after it has cooled down, poured onto ice. The product is extracted with ethyl acetate (3×100 ml) and dried (Na2 SO4). The mixture is filtered and the solvent is distilled off in vacuo.

1. customdoes not exceed 5° C
2. temperatureunder reflux for 5 h
3. temperatureafter it has cooled down
4. additionpoured onto ice
5. extractionThe product is extracted with ethyl acetate (3×100 ml)
6. customdried (Na2 SO4)
7. filtrationThe mixture is filtered
8. distillationthe solvent is distilled off in vacuo