反应详情

To a solution of ethyl 3-methyl-4-methoxybenzofuran-2-carboxylate (1.00 g, 4.27 mmol) and benzoyl chloride (1.80 g, 12.81 mmol) in 1,2-dichloroethane (12 mL) was added aluminum chloride (1.71 g, 12.81 mmol) in portions. The mixture was heated to reflux for 1.5 hours then allowed to cool and poured into 2N HCl (50 mL). The resulting mixture was extracted with methylene chloride (3×30 mL) and the combined extracts washed with saturated NaHCO3 (3×25 mL), dried (Na2SO4), and concentrated. The crude product was purified by preparative HPLC, using 25% ethyl acetate in hexane as eluant, to afford ethyl 3-methyl-4-methoxy-7-benzoylbenzofuran-2-carboxylate mp. 137°-139° C.; 1H NMR d 1.27 (2H, t, J=6 Hz), 2.67 (3H, s), 3.95 (3H, s), 4.28 (2H, q, J=6 Hz), 6.66 (1H, d, J=8 Hz), 7.44 (3H, m), 7.72 (3H, m).

1. temperatureThe mixture was heated
2. temperatureto reflux for 1.5 hours
3. temperatureto cool
4. extractionThe resulting mixture was extracted with methylene chloride (3×30 mL)
5. washthe combined extracts washed with saturated NaHCO3 (3×25 mL)
6. dry with materialdried (Na2SO4)
7. concentrationconcentrated
8. customThe crude product was purified by preparative HPLC