反应详情

To a suspension of 2-amino-5-bromo-3-nitropyridine (2.0 g, 9.17 mmole) in absolute EtOH (50 mL) was added SnCl2 hydrate (9.3 g, 41.3 mmole), then the mixture was heated to reflux. After 3 hr the mixture was cooled to RT and concentrated. The residue was taken up in 2.0 M NaOH and extracted with EtOAc (3×). The combined organic layers were dried (MgSO4), filtered, and concentrated to give the title compound (1.69 g, 98%) which was sufficiently pure for use in the next step: MS (ES) m/e 188/190 (M+H)+.

1. temperaturethe mixture was heated to reflux
2. concentrationconcentrated
3. extractionextracted with EtOAc (3×)
4. dry with materialThe combined organic layers were dried (MgSO4)
5. filtrationfiltered
6. concentrationconcentrated