反应详情

Into a solution of 3-cyano-5-hydroxypyridine (0.42 g, 3.50 mmol) in 1-propanol (40 ml) was passed hydrogen chloride gas under ice-cooling for 30 minutes. The reactor was tight sealed, and the mixture was stirred at room temperature for 20 hours. After the reaction was completed, the reaction mixture was concentrated under reduced pressure. To the solution of the residue in acetonitrile (20 ml) was then added an aqueous solution (30 ml) of cyanamide (0.88 g, 20.9 mmol), Na2HPO4 (1.5 g, 10.6 mmol) and NaH2PO4 ·2H2O (3.27 g, 21.0 mmol), and the mixture was stirred at room temperature for 6 hours. The reaction mixture was adjusted to pH 7.0 with a saturated aqueous sodium hydrogen carbonate solution and extracted with chloroform (50 ml×3). The chloroform layer was dried over anhydrous sodium sulfate and concentrated under reduced pressure to give a crude product of propyl N-cyano-5-hydroxy-3-pyridinecarboximidate (0.26 g).

1. temperaturecooling for 30 minutes
2. concentrationthe reaction mixture was concentrated under reduced pressure
3. stirringthe mixture was stirred at room temperature for 6 hours
4. extractionextracted with chloroform (50 ml×3)
5. dry with materialThe chloroform layer was dried over anhydrous sodium sulfate
6. concentrationconcentrated under reduced pressure