反应详情

—Pyridium p-toluenesulfonate (6.32 g) was added to a solution of (3β)-3-hydroxypregn-5-en-20-one (1; 100 g) in dichloromethane (600 ml) and ethyl vinyl ether (200 ml). After stirring of the reaction mixture for 1 h at room temperature triethylamine (20 ml) was added, whereupon the mixture was poured into a saturated aqueous solution of sodium hydrogen carbonate (1 l). The product was extracted into dichloromethane; the combined organic phases were washed with brine, dried over sodium sulfate, and concentrated under reduced pressure to give (3β)-3-[(1-ethoxyethyl)oxy]pregn-5-en-20-one (2; 125.6 g), which was used in the following step without further purification.

1. additionwas added, whereupon the mixture
2. extractionThe product was extracted into dichloromethane
3. washthe combined organic phases were washed with brine
4. dry with materialdried over sodium sulfate
5. concentrationconcentrated under reduced pressure