P(Cl)(Cl)([Cl:3])=O.[C:6]([OH:15])(=[O:14])[C:7]1[CH:12]=[CH:11][N+:10]([O-])=[CH:9][CH:8]=1>>[Cl:3][C:9]1[CH:8]=[C:7]([CH:12]=[CH:11][N:10]=1)[C:6]([OH:15])=[O:14]Phosphorus oxychloride (220.7 g) was added to isonicotinic acid N-oxide (50.064 g), and the mixture was stirred on an oil bath at 120° C. for 7 hours. The reaction mixture was slowly poured into ice water with vigorously stirring to precipitate light yellow crystals. The mixture was adjusted to approximately pH 4 with 4N NaOH aqueous solution. The resulting crystals were filtered out, washed with water, and dried by vacuum heating (60° C.) to obtain the above-captioned compound ([9]-(92)-467) (37.845 g).
Wird geladen…