7alpha-Chloro-5,6beta-epoxy-15beta,16beta-methylen-3beta-pivaloyloxy-5beta-androstan-17-one → 5-Hydroxy-15 beta,16 beta-methylene-3 beta-pivaloyloxy-5 beta-androst-6-en-17-one

Beteiligte Stoffe

Reaktionsschritte

A solution of 196 g of 7α-chloro-5,6β-epoxy-15β,16β-methylene-3β-pivaloyloxy-5β-androstan-17-one in 500 ml of acetic acid and 800 ml of tetrahydrofuran is combined at 70° C. with 392 g of zinc dust in two portions at an interval of 30 minutes and stirred for one hour at this temperature. After cooling, the zinc is filtered off over "Celite" and washed with 5 l of methylene chloride. The combined filtrates are combined with 1.5 l of water and neutralized under agitation by adding solid sodium bicarbonate. The organic phase is then washed with water, dried over sodium sulfate, and concentrated under vacuum. By trituration of the resultant solid product with ethyl acetate, 134.7 g of 5-hydroxy-15β,16β-methylene-3β-pivaloyloxy-5β-androst-6-en-17-one is obtained, mp 242°≥243° C.

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