反应 #2146685

反应方程式

2-bromo-3-methoxy-6-nitropyridine

hydrazine monohydrate

→

2-amino-5-methoxypyridine

收率 88.3%

溶剂

ethanol

反应条件

后处理

1. 1
   温度After the reaction mixture was refluxed for 70 minutes
2. 2
   过滤Then, after palladium-carbon was filtered off
3. 3
   洗涤the residue was washed with ethanol
4. 4
   浓缩The combined solution was concentrated under reduced pressure
5. 5
   workup.ADDITIONThen, 1300 mL of water and 130 mL of conc. aqueous ammonia were added to the concentrate
6. 6
   萃取the resulting mixture was extracted eight times with chloroform
7. 7
   干燥The combined chloroform layer was dried over anhydrous sodium sulfate
8. 8
   浓缩concentrated under reduced pressure
9. 9
   workup.DISTILLATIONThe resulting crude product was distilled under reduced pressure

实验过程

55.6 g (corresponding to 0.239 mol) of 2-bromo-3-methoxy-6-nitropyridine was dissolved in 1700 mL of ethanol, and 37.3 g (50% wet) of 10% palladium-carbon was added thereto under argon stream. To the mixture, 283 mL of hydrazine monohydrate was then added dropwise. After the reaction mixture was refluxed for 70 minutes, the reaction solution was cooled down to room temperature. Then, after palladium-carbon was filtered off, the residue was washed with ethanol, and the washings were combined with the filtrate. The combined solution was concentrated under reduced pressure. Then, 1300 mL of water and 130 mL of conc. aqueous ammonia were added to the concentrate, and the resulting mixture was extracted eight times with chloroform. The combined chloroform layer was dried over anhydrous sodium sulfate and concentrated under reduced pressure. The resulting crude product was distilled under reduced pressure to obtain 26.2 g (corresponding to 0.211 mol) of 2-amino-5-methoxypyridine (FIG. 2, Step 3).

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