反应详情

To 4,5,6-trimethylpyrimidin-2-ol (3.69 g, 26.7 mmol) was added POCl3 (21.7 mL, 26.7 mmol) followed by Et2NPh (2.17 mL, 13.6 mmol) dropwise. The mixture was heated at reflux for 48 h and then added to ice dropwise. The aqueous layer was extracted with EtOAc (2×). Extraction was difficult due to a large amount of precipitate. The aqueous layer pH was adjusted to pH 4-5 with 28% NH4OH and was filtered through Celite®. The aqueous layer was then extracted with DCM and the combined organic extracts dried over Na2SO4, filtered and concentrated in vacuo to a yellow solid. Chromatography (FCC) (0 to 30% EtOAc/Hex) afforded 2-chloro-4,5,6-trimethylpyrimidine (4.26 g, 100%).

1. temperatureThe mixture was heated
2. temperatureat reflux for 48 h
3. additionadded to ice dropwise
4. extractionThe aqueous layer was extracted with EtOAc (2×)
5. extractionExtraction
6. filtrationwas filtered through Celite®
7. extractionThe aqueous layer was then extracted with DCM
8. dry with materialthe combined organic extracts dried over Na2SO4
9. filtrationfiltered
10. concentrationconcentrated in vacuo to a yellow solid