反应详情

C-1. 8-Ethyl-2-(4-pyridinyl)pyrido[2,3-d]pyrimidin-5(8H)-one--A mixture containing 12.7 g of 2-(4-pyridinyl)pyrido[2,3-d]pyrimidin-5(8H)-one, 2.74 g of 50% sodium hydride in mineral oil and 300 ml of dimethylformamide was stirred at room temperature until evolution of hydrogen ceased. The mixture was heated gently with stirring on a steam bath for 30 minutes, one drop diisopropylamine was added followed by 100 mg of sodium hydride and gentle heating with stirring was continued for another 45 minutes. The mixture was then cooled to room temperature and to it was added dropwise with stirring at room temperature 8.85 g of ethyl iodide. The reaction mixture was stirred at room temperature for three hours and then heated gently with stirring on a steam bath for 30 minutes. The solvent was then distilled off in vacuo and the residue was shaken well with a mixture of water and chloroform. The water layer was extracted several times with chloroform and the chloroform extracts were combined with the chloroform layer. The combined chloroform solution was dried over anhydrous sodium sulfate, the mixture filtered, and the filtrate treated with decolorizing charcoal and filtered. The chloroform was distilled off in vacuo and the remaining 12 g of solid residue was dissolved in 300 ml of hot isopropyl alcohol, the hot alcohol solution treated with decolorizing charcoal and filtered. The filtrate was concentrated to a volume of about 150 ml and cooled. The precipitated solid was collected, washed with a small quantity of cold isopropyl alcohol, and dried at 65° C. in vacuo to produce 6.8 g of 8-ethyl-2-(4-pyridinyl)pyrido[2,3-d]pyrimidin-5(8H)-one, m.p. 200°-202° C. Additional product was obtained from the mother liquor.

1. temperatureThe mixture was heated gently
2. temperaturegentle heating
3. stirringwith stirring
4. waitwas continued for another 45 minutes
5. additionwas added dropwise
6. stirringThe reaction mixture was stirred at room temperature for three hours
7. temperatureheated gently
8. stirringwith stirring on a steam bath for 30 minutes
9. distillationThe solvent was then distilled off in vacuo
10. stirringthe residue was shaken well with a mixture of water and chloroform
11. extractionThe water layer was extracted several times with chloroform
12. dry with materialThe combined chloroform solution was dried over anhydrous sodium sulfate
13. filtrationthe mixture filtered
14. additionthe filtrate treated with decolorizing charcoal
15. filtrationfiltered
16. distillationThe chloroform was distilled off in vacuo
17. dissolutionthe remaining 12 g of solid residue was dissolved in 300 ml of hot isopropyl alcohol
18. additionthe hot alcohol solution treated with decolorizing charcoal
19. filtrationfiltered
20. concentrationThe filtrate was concentrated to a volume of about 150 ml
21. temperaturecooled
22. customThe precipitated solid was collected
23. washwashed with a small quantity of cold isopropyl alcohol
24. customdried at 65° C. in vacuo