Реакция #162817

Уравнение реакции

1,3-diphenylurea

malonic acid

→

1,3-diphenyl-pyrimidine-2,4,6-trione

Выход 40.0%

Растворители

Acetic anhydride

Условия реакции

Обработка

1. 1
   workup.ADDITIONwas added under a nitrogen atmosphere
2. 2
   workup.STIRRINGThe mixture was stirred at 100° C. for 1.5 hrs
3. 3
   Температураto cool to room temperature
4. 4
   КонцентрированиеThe reaction mixture was concentrated under reduced pressure
5. 5
   workup.ADDITIONEthanol (500 ml) was added to the residue
6. 6
   workup.STIRRINGthe mixture was stirred at 90° C
7. 7
   ТемператураWhen the mixture was cooled to 40° C.
8. 8
   Фильтрацияthe crystals were collected by filtration
9. 9
   Промывкаwashed with ethanol
10. 10
    Другоеdried

Методика

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%).

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