反应详情

To a suspension of methyl 2-(4-ethyl-6-oxo-2-(piperidin-1-yl)-1,6-dihydropyrimidin-5-yl)pentanoate (2.53 g; 7.86 mmol) in dry toluene (15 mL) under nitrogen atmosphere were 5carefully added phosphorus oxychloride (7.30 mL; 79 mmol) and dimethylaniline (0.794 mL; 6.29 mmol) and the reaction mixture was heated under reflux for 3 h. The volatiles were removed under reduced pressure (while the reaction mixture was still at elevated temperature), the residue was cooled in an ice-bath and quenched by adding crushed ice and a saturated solution of sodium hydrogen carbonate until neutralization. The aqueous layer was extracted with ethyl acetate, the organics were collected, 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 0.352 g (8.6%, over 3 last steps) of the title compound as a yellow oil.

1. temperaturethe reaction mixture was heated
2. temperatureunder reflux for 3 h
3. customThe volatiles were removed under reduced pressure (while the reaction mixture
4. temperaturewas cooled in an ice-bath
5. customquenched
6. additionby adding
7. customcrushed ice
8. extractionThe aqueous layer was extracted with ethyl acetate
9. customthe organics were collected
10. dry with materialdried over magnesium sulphate
11. filtrationfiltered
12. concentrationconcentrated under reduced pressure
13. customPurification by flash-chromatography on silica gel using a gradient of ethyl acetate (1-10%) in heptane