反应详情

1,2-Dibromoethane (1.50 mL, 17.4 mmol) was added to 5-Morpholin-4-yl-2-nitro-phenol (0.792 g, 3.53 mmol) and Potassium carbonate (1.71 g, 12.4 mmol) in Acetonitrile (40 mL) and the reaction was stirred under an atmosphere of Nitrogen at room temperature for 72 h (no change by HPLC), then was brought to reflux. After 4d, 1H-NMR indicated that the assumed starting material my LCMS was in actuality the 2:1 phenol-dibromoethane adduct. The reaction was cooled, diluted with ethyl acetate and filtered, conc. onto 5 g Celite. Chromatography (ISCO, 40 g, 0-40% EtOAc:Hex) afforded 4-[3-(2-Bromo-ethoxy)-4-nitro-phenyl]-morpholine (447 mg, 38%) as a colorless oil. 1H-NMR (CDCl3): 7.99 (d, 1H, J=8.8 Hz), 6.48 (m, 1H), 6.36 (d, 1H, J=1.5 Hz), 4.39 (t, 2H, J=6.8 Hz), 3.85 (t, 4H, J=4.8 Hz), 3.71 (t, 2H, J=6.8 Hz), 3.34 (t, 4H, J=4.8 Hz).

1. temperatureto reflux
2. temperatureThe reaction was cooled
3. filtrationfiltered, conc. onto 5 g Celite