反应详情

To a 250-mL round bottom flask was added 3-ethylaniline (10.1 g, 83.2 mmol), bromoacetaldehyde diethyl acetal (10.8 g, 54.8 mmol) and sodium bicarbonate (7.04 g, 83.8 mmol) in absolute ethanol (40 mL). The resulting mixture was stirred at reflux for 5 d. The mixture was concentrated, diluted with ether (30 mL) and washed with water (2×60 mL). The organic solution was dried (MgSO4) and concentrated at reduced pressure. The residue was purified by flash chromatography (SiO2, 5% then 15% EtOAc/hexanes) to give the title compound (4.5 g, 75%) as a white solid. 1H NMR (DMSO-d6) δ 6.98 (m, 1H), 6.42 (m, 2H), 5.34 (m, 1H), 4.53 (m, 1H), 3.59–3.35 (m, 4H), 3.19 (m, 2H), 2.41 (m, 2H), 1.17 (m, 9H).

1. temperatureat reflux for 5 d
2. concentrationThe mixture was concentrated
3. additiondiluted with ether (30 mL)
4. washwashed with water (2×60 mL)
5. dry with materialThe organic solution was dried (MgSO4)
6. concentrationconcentrated at reduced pressure
7. customThe residue was purified by flash chromatography (SiO2, 5%