反应详情

温度

250 °C

To diethyl [(4-quinazolinylamino)methylene]propanedioate (16.0 g) was added diphenylether (70 ml) which had been heated at 250° C. in advance. The reaction mixture was stirred at 250°-260° C. for 20 minutes and cooled to ambient temperature. To the resultant mixture was added hexane. The mixture was stirred to give crystals, which was washed with hexane and dried. The crude crystals were dissolved in ethyl acetate under heating. After insoluble materials were removed by filtration, the filtrate was concentrated under reduced pressure to a volume of 200 ml. To the concentrate was added hexane and the mixture was allowed to stand at ambient temperature to precipitate crystals, which were separated by filtration, washed with a mixture of ethyl acetate and hexane and dried to give crystalline ethyl 4-oxo-4H-pyrimido[1,2-c]quinazoline-3-carboxylate (12.4 g).

1. temperaturecooled to ambient temperature
2. stirringThe mixture was stirred
3. customto give crystals, which
4. washwas washed with hexane
5. customdried
6. dissolutionThe crude crystals were dissolved in ethyl acetate
7. temperatureunder heating
8. customAfter insoluble materials were removed by filtration
9. concentrationthe filtrate was concentrated under reduced pressure to a volume of 200 ml
10. additionTo the concentrate was added hexane
11. customto stand at ambient temperature
12. customto precipitate crystals, which
13. customwere separated by filtration
14. washwashed with a mixture of ethyl acetate and hexane
15. customdried