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 1 N 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