反应详情

—Aluminium isopropoxide (18.1 g) was added to a solution of (3β,20S)-pregn-5-ene-3,20-diol 20-acetate (21.9 g) in dry toluene (252 ml) and dry 2-butanone (156 ml). The mixture was heated under reflux for 2 h, then cooled, whereupon a solution of potassium sodium tartrate tetrahydrate (91.4 g) in water (90 ml) was added. The mixture was stirred for 30 min. and filtered. The filtrate was poured into brine and the product extracted into ethyl acetate. The combined organic phases were washed with brine, dried over sodium sulfate, and concentrated under reduced pressure. Column chromatography afforded (20S)-20-(acetyloxy)pregn-4-en-3-one (compound 6; 17.9 g).

1. temperatureThe mixture was heated
2. temperatureunder reflux for 2 h
3. additionwas added
4. filtrationfiltered
5. additionThe filtrate was poured into brine
6. extractionthe product extracted into ethyl acetate
7. washThe combined organic phases were washed with brine
8. dry with materialdried over sodium sulfate
9. concentrationconcentrated under reduced pressure