反应详情

50 ml. of NaOEt (0.5 g. Na -0.021 mole) was added to 3.4 g. (0.021 mole) of ethyl malonate and stirred 10 minutes, then evaporated to dryness. DMF was added until a solution was achieved and then 3.2 g. (0.011 mole) of 1-(2-methoxyethyl)-7-phenyl-2H-pyrimido[4,5-d][1,3]oxazine-2,4(1H)-dione was added and this mixture refluxed 2 hours. The chilled reaction was poured into dilute HCl and the ensuing precipitate filtered off and rinsed with water. Recrystallization from ethyl acetate gave 3.5 g. of the title product--m.p. 178°-179° C.

1. customevaporated to dryness
2. additionDMF was added until a solution
3. temperaturethis mixture refluxed 2 hours
4. customThe chilled reaction
5. filtrationthe ensuing precipitate filtered off
6. washrinsed with water
7. customRecrystallization from ethyl acetate
8. customgave 3.5 g