Long-Range Effect of 17-Substituents in 3-Oxo Steroids on 4,5-Double Bond Hydrogenation

Abstract

The long-range effect of substituents in the 17-position on the hydrogenation of double bond of the steroidal ∆4-3-ketones in acetic acid on a platinum catalyst is described in a series of testosterone (1) and epitestosterone (5) esters with carboxylic acids of varying alkyl chain length. The ratio 5α- to 5β-products is affected by the nature of substituents in the position 17.