反应详情

A mixture of N-(2-bromo-6-nitrophenyl)-5-fluoropyridin-3-amine (5.686 g, 18.22 mmol) and tin(II) chloride dihydrate (20.56 g, 91 mmol) in EtOAc (121 mL) was heated under reflux with stirring. After 2.5 h, the mixture was cooled to rt. The cooled mixture was poured into 10M aqueous NaOH solution (150 mL). The mixture was extracted with EtOAC (100 mL×2) washed with water (100 mL×2), brine (100 mL×1), dried over Mg2SO4, filtered, and concentrated in vacuo. The crude material was absorbed onto a plug of silica gel and purified by chromatography through a Redi-Sep™ pre-packed silica gel column (120 g), eluting with a gradient of 0% to 30% EtOAc in hexane, to provide 6-bromo-N1-(5-fluoropyridin-3-yl)benzene-1,2-diamine as brown syrupy solid: 1H NMR (400 MHz, DMSO-d6) δ ppm 7.84 (1H, s), 7.76-7.82 (2H, m), 6.91-6.98 (1H, m), 6.81-6.87 (1H, m), 6.77 (1H, dd, J=8.0, 1.4 Hz), 6.39 (1H, dt, J=11.7, 2.3 Hz), 5.28 (2H, s); LC-MS (ESI) m/z 282.0 [M+H (79Br)]+ and 283.9 [M+H (81Br)]−.

1. temperaturewas heated
2. temperatureunder reflux
3. extractionThe mixture was extracted with EtOAC (100 mL×2)
4. washwashed with water (100 mL×2), brine (100 mL×1)
5. dry with materialdried over Mg2SO4
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customThe crude material was absorbed onto a plug of silica gel
9. custompurified by chromatography through a Redi-Sep™ pre-packed silica gel column (120 g)
10. washeluting with a gradient of 0% to 30% EtOAc in hexane