反应详情

To a mixture of tert-butyl 3-((2-bromo-5-nitropyridin-4-yl)amino)piperidine-1-carboxylate. (1.24 g, 3.01 mmol, 1.0 eq) and NH4Cl (2.43 g, 45 mmol, 15 eq) was added a 2:1 mixture EtOH/water (30 mL). The reaction mixture was heated to reflux, then iron powder (0.67 g, 12 mmol, 3.5 eq) was added in portions over 15 min and the suspension was continued to be heated at refluxed for 16 h. The reaction mixture was cooled to rt, diluted with CH2Cl2 (300 mL) and filtered through celite. The organic layer was washed with water (50 mL×2) and brine (50 mL), dried (Na2SO4), filtered and concentrated in vacuo to give the title compound (1.2 g, 100%) which was used to next step without further purification. 1H NMR (400 MHz, CDCl3) δ: 7.66 (s, 1H), 6.63 (s, 1H), 4.51-4.39 (m, 1H), 3.89-3.86 (m, 1H), 3.67-3.63 (m, 1H), 3.41-3.10 (m, 4H), 2.09-1.95 (m, 1H), 1.74-1.60 (m, 3H), 1.47 (s, 9H). ESI-MS (M+H+): 371.0.

1. temperatureThe reaction mixture was heated
2. temperatureto reflux
3. temperatureto be heated
4. temperatureat refluxed for 16 h
5. filtrationfiltered through celite
6. washThe organic layer was washed with water (50 mL×2) and brine (50 mL)
7. dry with materialdried (Na2SO4)
8. filtrationfiltered
9. concentrationconcentrated in vacuo