反应详情

—Sodium (8.98 g) was added in small portions in the course of 2 h to a refluxing solution of (3β)-3-[(1-ethoxyethyl)oxy]pregn-5-en-20-one (20 g) in dry n-butanol (587 ml). Heating was continued for another 2 h; then the reaction mixture was cooled and poured into a saturated aqueous solution of sodium hydrogen carbonate (1.5 l). The product was extracted into ethyl acetate; the combined organic phases were washed with brine, dried over sodium sulfate, and concentrated under reduced pressure. Column chromatography of the crude product afforded (3β,20R)-3-[(1-ethoxyethyl)oxy]pregn-5-en-20-ol (compound 3b; 5.08 g) and (3β,20S)-3-[(1-ethoxyethyl)oxy]pregn-5-en-20-ol (compound 3a; 7.21 g).

1. temperatureHeating
2. temperaturethen the reaction mixture was cooled
3. extractionThe product was extracted into ethyl acetate
4. washthe combined organic phases were washed with brine
5. dry with materialdried over sodium sulfate
6. concentrationconcentrated under reduced pressure