反应详情

温度

100 °C

A suspension mixture of 2-amino-5-nitro-3,4-dihydropyrimidin-4-one (1.5 g, 9.61 mmol) and phosphorus oxychloride (27 mL, 0.29 mol) was heated under reflux (100° C.) for 18 hr. The reaction mixture turned into a yellow solution. The mixture was cooled to RT before being concentrated in vacuo. DCM (10 mL) was added and concentrated in vacuo was repeated. Ice (ca 5 g) was added, resulted in a sticky solid. DCM (20 mL) was added and the mixture was quenched by addition to an ice-cold saturated aqueous NaHCO3 solution (150 mL). The pH of mixture was adjusted to basic by final addition of 2M aq K2CO3. Attempt to extract product with DCM resulted in emulsion formation. Emulsion was removed by suction filtration. The aqueous layer was extracted with EtOAc (3×50 mL). The EtOAc extracts were combined with the DCM extract, dried over Na2SO4, filtered and concentrated in vacuo to afford the title compound as a yellow powder: 1H NMR (500 MHz, DMSO) δ 8.40-8.48 (2H, m), 9.02 (1H, s). LC-MS: m/z=+174.9 (M+H)+.

1. temperaturewas heated
2. temperatureThe mixture was cooled to RT
3. concentrationbefore being concentrated in vacuo
4. additionDCM (10 mL) was added
5. concentrationconcentrated in vacuo
6. additionIce (ca 5 g) was added
7. customresulted in a sticky solid
8. customthe mixture was quenched by addition to an ice-cold saturated aqueous NaHCO3 solution (150 mL)
9. additionaddition of 2M aq K2CO3
10. extractionto extract product with DCM
11. customresulted in emulsion formation
12. customEmulsion was removed by suction filtration
13. extractionThe aqueous layer was extracted with EtOAc (3×50 mL)
14. extractionextract
15. dry with materialdried over Na2SO4
16. filtrationfiltered
17. concentrationconcentrated in vacuo