反应详情

Nitroguanidine (53.1 g) was added to a solution of sodium (17.6 g) in methanol (500 ml). The mixture was heated under reflux for 45 minutes. Ethyl α-isobutylacetoacetate (95.0 g) was then added dropwise to the refluxing mixture over 30 minutes. Refluxing was continued for a further 61/2 hours. Most of the methanol was removed and the residue was dissolved in water. Unreacted β-keto-ester was removed by extraction with chloroform and the solution was acidified with concentrated hydrochloric acid. The separated solid was washed with water and dried, giving 5-isobutyl-6-methyl-2-nitraminopyrimid-4(3H)-one (formula IV, R1 = CH3, R = isobutyl) (73.2 g). A sample recrystallised from ethanol had a melting point of 179°-181° (decomp.).

1. temperatureThe mixture was heated
2. temperatureunder reflux for 45 minutes
3. temperatureRefluxing
4. custom2 hours
5. customMost of the methanol was removed
6. dissolutionthe residue was dissolved in water
7. customwas removed by extraction with chloroform
8. washThe separated solid was washed with water
9. customdried