反应详情

温度

40 °C

Compound C5 (48.1 g, 133 mmol) was dissolved in acetic acid (444 mL) and treated with zinc powder (113 g, 1.73 mol). The reaction mixture, which had warmed to 40° C., was allowed to cool to room temperature and stir for 16 hours. Insoluble material was removed via filtration through a pad of diatomaceous earth, and the pad was washed with ethyl acetate (3×500 mL). The combined filtrates were neutralized with saturated aqueous sodium bicarbonate solution (2.5 L), and the aqueous layer was extracted with ethyl acetate (3×500 mL). The combined organic layers were washed with saturated aqueous sodium chloride solution (1 L), dried over sodium sulfate, filtered, and concentrated in vacuo to provide the product as a thick yellow oil, which was used in the following reaction without additional purification. Yield: 48.7 g, assumed quantitative. 1H NMR (400 MHz, CDCl3), characteristic peaks: δ 7.62-7.80 (br m, 1H), 7.28-7.39 (m, 5H), 6.94-7.06 (m, 1H), 6.83 (ddd, J=12.7, 8.5, 2.6 Hz, 1H), 4.61 (AB quartet, upfield doublet is broadened, JAB=12.2 Hz, ΔνAB=30.5 Hz, 2H), 4.22 (dd, J=11.6, 2.2 Hz, 1H), 3.83-3.92 (br m, 1H), 3.62-3.73 (br m, 1H), 3.56 (dd, J=10.2, 3.5 Hz, 1H), 3.34-3.41 (m, 1H), 2.26-2.43 (br m, 1H), 2.00-2.17 (br m, 1H), 1.65 (ddd, J=14.1, 4.5, 2.5 Hz, 1H).

1. temperatureto cool to room temperature
2. customInsoluble material was removed via filtration through a pad of diatomaceous earth
3. washthe pad was washed with ethyl acetate (3×500 mL)
4. extractionthe aqueous layer was extracted with ethyl acetate (3×500 mL)
5. washThe combined organic layers were washed with saturated aqueous sodium chloride solution (1 L)
6. dry with materialdried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated in vacuo