反应详情

温度

135 °C

4-Hydroxy-3-nitropyridine (10.0 g, 71.4 mmol) is added portionwise to a mechanically stirred mixture of phosphorous pentachloride (16.32 g, 78.6 mmol) and phosphorous oxychloride (16.2 mL) at 55-60° C. After the addition is complete, the temperature is raised to 130-140° C. for 4 hr. After cooling to room temperature, the phosphorous oxychloride is removed and the residue is cautiously treated with ice/water, made basic with sodium carbonate and extracted with ether. The combined extract is dried, filtered and concentrated to yield 4-chloro-3-nitropyridine (5.1 g, 45% yield) as a pale yellow solid.

1. additionAfter the addition
2. temperatureAfter cooling to room temperature
3. customthe phosphorous oxychloride is removed
4. additionthe residue is cautiously treated with ice/water
5. extractionextracted with ether
6. extractionThe combined extract
7. customis dried
8. filtrationfiltered
9. concentrationconcentrated