反应详情

Reflux a solution of 6-bromo-imidazo[1,2-a]pyridine-3-carbaldehyde (J. Med. Chem. 1970, 13(6), 1048-51; 0.45 g, 1.99 mmol), morpholine (1.7 g, 19.9 mmol), and acetic acid (0.12 mL, 1.99 mmol) in toluene (200 mL) for 3 h. Concentrate to dryness and re-dissolve in methanol (100 mL). Add sodium borohydride (0.226 g, 5.99 mmol) in portions and stir for 30 min. Concentrate to ˜25 mL, dilute with saturated aqueous sodium bicarbonate, extract into ethyl acetate, combine and concentrate. Flash chromatography gives the titled compound (0.25 g, 42%). MS ES+ m/e 295.8, 297.8 (M+1). 1H NMR (400 MHz, DMSO-d6) δ 8.69 (s, 1H), 7.54 (d, J=10 Hz, 1H), 7.51 (s, 1H), 7.35 (d, J=10 Hz, 1H), 3.81 (s, 2H), 3.52 (t, J=4 Hz, 1H), 2.35 (t,J=4 Hz, 4H).

1. concentrationConcentrate to dryness
2. dissolutionre-dissolve in methanol (100 mL)
3. concentrationConcentrate to ˜25 mL
4. additiondilute with saturated aqueous sodium bicarbonate
5. extractionextract into ethyl acetate
6. concentrationconcentrate