Abstract
In the synthesis of 17β-hydroxyandrostan-3-one from 3β-acetoxy-5-androsten-17-one, carbonyl group at 17-position is reduced to 17β-hydroxyl almost quantitatively by means of sodium borohydride without accompanying saponification of 3-ester. By catalytic hydrogenation over Raney nickel under high pressure and heating, double bond at 5-6 position of the steroidal B-ring is saturated and the trans-form is produced. In this case, aromatic ring at 17-ester is first reduced, followed by the double bond at 5-position. 3-Hydroxyl is oxidized to 3-keto group in a good yield on heating with activated alumina and cyclohexanone in nonpolar solvent. Finally, 17-ester is saponified quantitatively to 17β-hydroxyandrostan-3-one.
