Dehydroepiandrosterone → 7-Oxodehydroepiandrosterone 3-acetate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

The above solution of DHEA-Ac (2) in ethyl acetate (˜1000 ml) was taken in a 5L three necked flask fitted with a thermometer and a pressure equalizing dropping funnel. An aqueous solution of tert-butyl hydroperoxide (70% aqueous solution from Aldrich, 270 ml, 6.0 equivalents) was added and the mixture was cooled to 0-5° C. Aqueous sodium hypochlorite solution (950 ml, 5.25% solution, purchased as house hold bleach) was added dropwise under good stirring to the cooled solution during a period of ten hours at 0-5° C. After completion of addition, the lower aqueous layer was removed and the organic (ethyl acetate) layer was stirred with sodium sulfite solution (100.0 gm in 300 ml of water) for 3 hours at 40-45° C. The aqueous yellow layer was removed and the organic layer was washed twice with 100 ml of half saturated brine, dried over anhydrous magnesium sulfate and concentrated to 50 ml volume. On triturating with hexane, 3β-acetoxyandrost-5-en-7,17-dione (7-oxo-DHEA-Ac, 3) crystallized out as a white solid, yield 79.4 gm (66.5%, based on DHEA), purity (HPLC) 98.86%. The resulting solid was recrystallized from ethanol, providing 3β-acetoxyandrost-5-en-7,17-dione (3) as white crystalline solid (70.0 gm, purity (HPLC) 99.8%, melting point 185-186° C.

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