反应详情

2-(3-Nitroanilino)-3-carbamoylpyridine (20 g, 77.5 mmole) was dissolved in tetrahydrofuran (2000 ml). Sodium hydride (60% dispersion in oil) (12.4 g, 310.0 mmole) was washed in hexanes and added to the solution. The solution was stirred for 5 minutes at room temperature under an inert atmosphere. To the solution, CDI (1,1'-carbonyldiimidazole) (18.8 g, 116.2 mmole) was added in a gradual manner over a period of 15 minutes, the resulting mixture was stirred at room temperature for 1 hour and subsequently refluxed for 24 hours. The solvent was removed resulting in a brown residue. Water was added to the residue and the resulting solution was extracted with ethyl acetate (5×300 ml). The phases were separated and the product was recrystallized from EtOAc/Et2O yielding a 12 g (42.4 mmole, 54.5% yield) of 1-N-(3-nitrophenyl)pyrido[2,3-d]pyrimidine-2,4(1H,3H)-dione (mp 262°-263° C.).

1. additionadded to the solution
2. stirringthe resulting mixture was stirred at room temperature for 1 hour
3. temperaturesubsequently refluxed for 24 hours
4. customThe solvent was removed
5. customresulting in a brown residue
6. extractionthe resulting solution was extracted with ethyl acetate (5×300 ml)
7. customThe phases were separated