Studies on A-Norsteroids. III. Hydrogenations of A-Nor-Δ³⁽⁵⁾-steroids Substituted at C₁ and C₂-Positions

Abstract

Catalytic hydrogenations of the A-nor-Δ³⁽⁵⁾-steroid derivatives have been described. The unsaturated 1β, 2β, 17β-(I) and 1β, 2α, 17β-(II) triols on hydrogenation with palladium-charcoal afforded afforded the saturated 1β, 17β-diol(IIIa) accompanied with hydrogenolysis of their allylic C₂-hydroxyl group, while with Adams' catalyst gave the respective trihydroxy-5β-steroids (IVa) and (VIa). The unsaturated 1β, 17β-dihydroxy-2-one (VIIa) was hydrogenated over palladium-charcoal into the corresponding 5β-steroid (VIIIa), but with Adams' catalyst to yield exclusively the 5α-steroid (XIa).