反应详情

温度

40 °C

To a solution of 5-bromo-3-nitropyridine-2-carbonitrile (4.71 g, 20.7 mmol) in MeOH (319 mL) under N2 was added tin(II) chloride dihydrate (27.97 g, 123.9 mmol). The reaction was heated to 40° C. for 40 minutes, concentrated in vacuo, and azeotroped with toluene. The residue was dissolved in ethyl acetate, and 10% aqueous sodium bicarbonate was added till the solution was basic. The aqueous layer was extracted 3× with CHCl3 and the combined organics were dried over Na2SO4, filtered and concentrated under vacuum to provide 3-amino-5-bromopyridine-2-carboxamide that gave a mass ion (ES+) of 218.2 for M+H+(81Br).

1. concentrationconcentrated in vacuo
2. customazeotroped with toluene
3. dissolutionThe residue was dissolved in ethyl acetate
4. addition10% aqueous sodium bicarbonate was added till the solution
5. extractionThe aqueous layer was extracted 3× with CHCl3
6. dry with materialthe combined organics were dried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated under vacuum