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To a solution of 4-(5-Bromo-6-nitropyridin-3-yl)morpholine (2 g, 6.9 mmol) in MeOH (150 mL) in a round bottom flask was added Zn dust (4.54 g, 69.4 mmol). The reaction mixture was cooled to 0° C. Solid NH4Cl (3.71 g, 69.4 mmol) was added in portions, over 5 min. The heterogeneous reaction mixture was stirred at room temperature for 2 h, filtered through a plug of Celite washing the filter cake with methanol and ethanol. The filtrate was concentrated to a brownish solid which was purified by flash column chromatography on silica gel (ISCO, 80 g column, 0-70% EtOAc/heptane in 15 min and 70% EtOAc to 25 min), obtaining 3-bromo-5-morpholinopyridin-2-amine (936 mg, 52.2%) as a slightly off white solid. LCMS (m/z): 258.2 (MH+), 0.35 min; 1H NMR (400 MHz, CDCl3) δ ppm 7.75 (d, J=2.3 Hz, 1H) 7.40-7.30 (m, 1H) 4.66 (br. s., 2H) 3.91-3.74 (m, 4H) 3.07-2.90 (m, 4H).

1. filtrationfiltered through a plug of Celite
2. washwashing the filter cake with methanol and ethanol
3. concentrationThe filtrate was concentrated to a brownish solid which
4. customwas purified by flash column chromatography on silica gel (ISCO, 80 g column, 0-70% EtOAc/heptane in 15 min and 70% EtOAc to 25 min)