反应详情

20 mλ of pyridine was added to 2-amino-3-bromo-5-nitropyridine (A) (21.8 g; 0.1 mole) in 300 ,λ of acetonitrile at room temperature in a stream of nitrogen followed by addition of benzoylchloride (24.4 g; 0.2 mole) and agitation for 3 hours. Then dilute hydrochloric acid (0.1N) was added to the resulting mixture. After extraction with ethyl acetate, the resulting ethyl acetate solution was dried over anhydrous sodium sulfate. The solvent was distilled off under a reduced pressure. The residue was recrystallized from methanol to give 3-bromo-2-benzoylamino-5-nitropyridine (B) (28.7 g; 89%).

1. extractionAfter extraction with ethyl acetate
2. dry with materialthe resulting ethyl acetate solution was dried over anhydrous sodium sulfate
3. distillationThe solvent was distilled off under a reduced pressure
4. customThe residue was recrystallized from methanol