反应详情

In a 50 milliliter round-bottom flask, 3-oxohexanoic acid ethyl ester (3.2 grams, 0.020 mol, obtained from Aldrich Chemical Co., Milwaukee, Wis.) was added at room temperature to a solution of 1-phenylbiguanide (3.5 grams, 0.020 mol, prepared as described in Part D of Example I) in anhydrous ethanol (15 milliliters). The mixture was heated at reflux and stirred for 4 hours. After a few minutes, all the components dissolved. Cooling the resulting yellow solution mixture to room temperature gave a colorless precipitate. The precipitate was isolated by filtration and thoroughly washed with water, then with cold ethanol (0° C.), and finally with acetone. The solid was then recrystallized from anhydrous ethanol, recovered by filtration, and dried under reduced pressure to give the targeted N-(6-oxo-4-propyl-1,6-dihydropyrimidin-2-yl)-N′-phenylguanidine as a colorless solid (3.90 grams, 72 percent yield): mp=196° C.; Exact mass calculated for C14H17N5O=271.1433. Measured High Resolution Mass Spectrum (MAB/HR/N2)=271.1431. Anal. Calcd for C14H17N5O: C, 61.98; H, 6.32; N, 25.81. Found: C, 62.32; H, 6.44; N, 25.68.

1. temperatureThe mixture was heated
2. temperatureat reflux
3. waitAfter a few minutes
4. dissolutionall the components dissolved
5. customgave a colorless precipitate
6. customThe precipitate was isolated by filtration
7. washthoroughly washed with water
8. customwith cold ethanol (0° C.)
9. customThe solid was then recrystallized from anhydrous ethanol
10. filtrationrecovered by filtration
11. customdried under reduced pressure