反应详情

To an 80% aqueous ethanol suspension (150 ml) of 5-chloro-3-nitropyridin-2-ol (15.0 g) and calcium chloride (9.54 g) was added iron powder (24.0 g), followed by stirring at room temperature for 30 minutes, and further under heating at reflux for 1 hour. After the temperature was brought back to room temperature, the reaction suspension was filtered through Celite. Water was added to the filtrate, and extracted 8 times with a methanol-dichloromethane (1:10) mixed solvent. The collected organic layer was dried over anhydrous sodium sulfate, and concentrated under reduced pressure to afford 3-amino-5-chloropyridin-2-ol (8.86 g).

1. temperaturefurther under heating
2. temperatureat reflux for 1 hour
3. customwas brought back to room temperature
4. filtrationthe reaction suspension was filtered through Celite
5. additionWater was added to the filtrate
6. extractionextracted 8 times with a methanol-dichloromethane (1:10)
7. additionmixed solvent
8. dry with materialThe collected organic layer was dried over anhydrous sodium sulfate
9. concentrationconcentrated under reduced pressure