Imidazole → 3-Oxo-17beta-(t-butyldimethylsilyloxymethyl)-4-androstene

Participants

Reaction Steps

To a solution of 3-oxo-17β-(hydroxymethyl)-4-androstene (15 g, 0.05 mol) in 200 ml DMF was added 5.8 g (0.085 mol) imidazole followed by 9.7 g (0.065 mol) t-butyldimethylsilyl chloride. The reaction mixture was stirred at room temperature under argon, for 2.5 hours. The reaction mixture was then poured into 250 ml ice water and washed 3 times with ethyl acetate. The combined organic layers were washed twice with cold 5% hydrochloric acid and once each with saturated sodium bicarbonate solution and brine. The organic layer was dried over sodium sulfate and evaporated. Recrystallization from methanol afforded 16.9 g (82%) of 3-oxo-17β-(t-butyldimethylsilyloxymethyl)-4-androstene as a white crystalline solid.

Provenance & Evidence