反应详情

温度

90 °C

Acetic anhydride (290 ml) was added to 1,3-diphenylurea 18 (148 g), malonic acid 4 (81.6 g) was added under a nitrogen atmosphere, and the mixture was stirred at 90° C. for 3 hrs. The mixture was stirred at 100° C. for 1.5 hrs and allowed to cool to room temperature. The reaction mixture was concentrated under reduced pressure. Ethanol (500 ml) was added to the residue, and the mixture was stirred at 90° C. When the mixture was cooled to 40° C., the crystals were collected by filtration, washed with ethanol and dried to give 1,3-diphenyl-pyrimidine-2,4,6-trione 19 (78.0 g, yield 40%).

1. additionwas added under a nitrogen atmosphere
2. stirringThe mixture was stirred at 100° C. for 1.5 hrs
3. temperatureto cool to room temperature
4. concentrationThe reaction mixture was concentrated under reduced pressure
5. additionEthanol (500 ml) was added to the residue
6. stirringthe mixture was stirred at 90° C
7. temperatureWhen the mixture was cooled to 40° C.
8. filtrationthe crystals were collected by filtration
9. washwashed with ethanol
10. customdried