反应详情

To a stirred mixture of 6-bromo-3-nitro-2-pyridinamine (2.5 g, 11.47 mmol) in a mixture of glacial HOAc (10 mL), MeOH (10 mL) and EtOH (10 mL) at 0° C. was added portionwise zinc dust (3.73 g, 57.35 mmol). The mixture was stirred at rt for 15 h. The mixture was filtered through Celite, and the filtrate was concentrated under reduced pressure. The residue was partitioned between saturated aq NaHCO3 and EtOAc. The organic layer was separated and the aqueous layer was extracted with additional EtOAc. The combined organic layers were washed with brine, separated and dried over MgSO4, filtered, and concentrated under reduced pressure to afford 6-bromopyridine-2,3-diamine (1.30 g, 60%) as a solid that did not require further purification. 1H NMR (300 MHz, DMSO-d6) δ 6.61 (d, J=7.7 Hz, 1H), 6.47 (d, J=7.7 Hz, 1H), 5.82 (s, 2H), 4.79 (s, 2H). LCMS (ESI) m/z 188 and 190 (M+H)+.

1. filtrationThe mixture was filtered through Celite
2. concentrationthe filtrate was concentrated under reduced pressure
3. customThe residue was partitioned between saturated aq NaHCO3 and EtOAc
4. customThe organic layer was separated
5. extractionthe aqueous layer was extracted with additional EtOAc
6. washThe combined organic layers were washed with brine
7. customseparated
8. dry with materialdried over MgSO4
9. filtrationfiltered
10. concentrationconcentrated under reduced pressure