反应详情

The crude 3-(methoxycarbonyl)-2-methylpyridine-1-oxide (35 g, 210 mmol) was added in small portion to POCl3 (300 g) at room temperature. After the addition, the reaction mixture was refluxed for 3 hours before it was concentrated in vacuo. The residue was poured into ice-water, neutralized with aq. NaHCO3 solution and extracted with AcOEt (125 mL×3). The combined organic layers were washed with brine, dried over anhy. NazSO4, filtered, and concentrated in vacuo to afford a crude product which was then purified by column chromatography to give title compound (12 g, yield 30%).

1. additionAfter the addition
2. temperaturethe reaction mixture was refluxed for 3 hours before it
3. concentrationwas concentrated in vacuo
4. additionThe residue was poured into ice-water
5. extractionextracted with AcOEt (125 mL×3)
6. washThe combined organic layers were washed with brine
7. customdried over anhy
8. filtrationNazSO4, filtered
9. concentrationconcentrated in vacuo
10. customto afford a crude product which
11. customwas then purified by column chromatography