Platinum-catalyzed Oxidation Δ⁴- and Δ⁵-Unsaturated and Saturated Steroidal Alcohols

Abstract

Platinum-catalyzed oxidation of Δ⁴-unsaturated and saturated 3-hydroxysteroids afforded the corresponding ketones in good or excellent yields. On the other hand, it is found that Δ⁵-unsaturated 3-hydroxysteroids, especially the 3β-epimers, have a low reactivity at the oxidation which gave complicated mixtures consisted of several oxidation products. 5β-Cholestanol afforded 5α-cholestanone, a product with a transformed A/B-ring juncture, in addition to 5β-cholestanone, Each of the pairs of double bond- and stereo-isomers of the steroids was distinguished with the aid of ¹H NMR spectroscopy.