Hydrochloric Acid → 6-Methylene-16-(phenylsulfinylmethyl)pregna-4,16-diene-3,20-dione

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Reaction Steps

17α-Acetyl-17β-hydroxy-6,16-dimethyleneandrosta-4-en-3-one (VA, Example 29, 8.0 g) is dissolved in methylene chloride (66 ml) and cooled to -20°. Trimethylamine (2.56 ml) at -20° and methylene chloride (5 ml) are mixed and the trimethylamine mixture transferred by syringe to the steroid solution. To the cold steroid solution was added phenylsulfonylchloride (1.0 equivalent) by a syringe pump over 1 hr. TLC shows the reaction approximately 80-85% complete. Phenylsulfonylchloride (0.25 equivalent) was added over approximately 10 min, TLC showing the reaction to be approximately 95% complete. Phenylsulfonylchloride (0.10 equivalent) was then added for a total of 1.35 equivalence, at which time TLC shows the reaction to be complete. Hydrochloric acid (10%, 40 ml) was added all at once, the temperature now being 7°, and the mixture stirred for about 10 min. The phases are separated. The aqueous portion is back extracted with methylene chloride (10 ml). The organic extracts are washed with phosphate buffer (25 ml) and back extracted with methylene chloride (10 ml). The organic extracts are combined, dried over sodium sulfate overnight at 20°-25°. This mixture is filtered and the filtrate concentrated under reduced pressure to an oil, which is the title compound.

Provenance & Evidence