反应详情

3-(3,5-dimethoxy-phenyl)-2-[4-(4-formylphenoxy)-phenyl]-acrylic acid methyl ester (21) was first prepared by converting the corresponding free acid (3) to the methyl ester by addition of DMF, K2CO3 and dimethyl sulfate in a manner analogous to Example 1 (f) above. Sodium borohydride (0.125 g, 3.3 mmol) was added to a suspension of 21 (1.26 g, 3 mmol) in ethanol (20 mL) and stirred at room temperature for 1 hr. The reaction was quenched with 5% aqueous HCl, and ethanol was evaporated under reduced pressure. Residue was taken up in ethyl acetate (50 mL) and washed with brine (2×20 mL), dried over anhydrous magnesium sulfate and evaporated. The crude product was purified by silica gel chromatography and eluted with hexanes-ethyl acetate (1:1). Yield: 1.14 g, 95.0%. Analysis: 1HNMR (DMSO-d6): δ 7.72 (s, 1H), 7.36 (d, J=8.8 Hz, 2H), 7.19 (d, J=8.8 Hz, 2H), 7.01 (d, J=8.4 Hz, 2H), 6.99 (d, J=8.4 Hz, 2H), 6.41 (t, J=2.4 Hz, 1H), 6.28 (d, J=2.4 Hz, 2H), 5.18 (t, J=6.4 Hz, 1H), 4.49 (d, J=4.8 Hz, 2H), 3.72 (s, 3H), 3.57 (s, 6H).

1. customThe reaction was quenched with 5% aqueous HCl, and ethanol
2. customwas evaporated under reduced pressure
3. washwashed with brine (2×20 mL)
4. dry with materialdried over anhydrous magnesium sulfate
5. customevaporated
6. customThe crude product was purified by silica gel chromatography
7. washeluted with hexanes-ethyl acetate (1:1)