反应详情

To a suspension of methyl 2-(4-methyl-6-oxo-2-(piperidin-1-yl)-1,6-dihydropyrimidin-5-yl)pentanoate (5.97 g; 19.42 mmol) in dry toluene (40 mL) under nitrogen atmosphere were carefully added phosphorus oxychloride (18.05 mL; 194 mmol) and dimethylaniline (1.961 mL, 15.54 mmol). The reaction was heated to reflux for 3 h and after cooling at room temperature, the volatiles were removed under reduced pressure and the remaining residue was cooled in an ice-bath and quenched by adding crushed ice and a saturated solution of sodium hydrogen carbonate until neutralization. The product was extracted twice with ethyl acetate and the combined organic layers were dried over magnesium sulphate, filtered and concentrated under reduced pressure. Purification by flash-chromatography on silica gel using a gradient of ethyl acetate (1-10%) in heptane furnished 2.45g (39%) of the title compound as a yellow oil.

1. temperatureThe reaction was heated
2. temperatureto reflux for 3 h
3. customthe volatiles were removed under reduced pressure
4. temperaturethe remaining residue was cooled in an ice-bath
5. customquenched
6. additionby adding
7. customcrushed ice
8. extractionThe product was extracted twice with ethyl acetate
9. dry with materialthe combined organic layers were dried over magnesium sulphate
10. filtrationfiltered
11. concentrationconcentrated under reduced pressure
12. customPurification by flash-chromatography on silica gel using a gradient of ethyl acetate (1-10%) in heptane