Triethylamine → 3beta-Tribenzylsilyloxy-7beta-hydroxy-15beta,16beta-methylene-5-androsten-17-one

Participants

Reaction Conditions

Reaction Steps

A solution of 15.7 g of 3β,7β-dihydroxy-15β,16β-methylene-5-androsten-17-one in 750 ml of methylene chloride is combined with 9 ml of triethylamine and 200 mg of dimethylaminopyridine and cooled to -20° C. Within 30 minutes, 19.4 g of tribenzylsilyl chloride in 10 ml of methylene chloride is added dropwise thereto. The reaction mixture is stirred for one hour at -20° C. and one hour at 0° C., diluted with methylene chloride, and washed with 1N hydrochloric acid, saturated sodium bicarbonate solution, and water. After drying over sodium sulfate, the mixture is concentrated under vacuum. Chromatography on silica gel with hexane-acetone yields 27.5 g of 3β-tribenzylsilyloxy-7β-hydroxy-15β,16β-methylene-5-androsten-17-one.

Provenance & Evidence