Water → 9-Dehydroandrostenedione

関与物質

反応手順

9α-Hydroxyandrostenedione (10.00 g.) is dissolved in methylene chloride (100 ml.) and cooled to 0°-5°. Chlorosulfonic acid (5 ml.) is added dropwise and the mixture stirred to 0.5 hour at 0°-5°. Water (50 ml.) is added dropwise while the temperature rises to 23°. The mixture is stirred for 5 minutes and the phases separated. The organic phase is washed with an aqueous sodium bicarbonate solution (10%, 25 ml.) and water (50 ml.) containing 10 ml. of a saturated sodium chloride solution. Each of the aqueous washes is back extracted with the same methylene chloride (25 ml.) which is then added to the organic phase. The organic phase is concentrated to approximately 50 ml. Heptane (100 ml.) is added and the mixture concentrated to approximately 50 ml. with the temperature reaching a maximum of about 35°. The mixture is cooled to 0°-5°, Stirred 0.5 hour, the solids are collected by filtration, under vacuum at 55° to give androsta-4,9(11)-diene-3,17-dione, 8.95 g. (89.5% weight yield, 95.0% chemical yield). GC (Example 1) shows 99% androsta-4,9(11)-diene-3,17-dione.

情報源と証拠