Catalytic reduction of 3β‐hydroxyandrost‐4‐ene‐17‐one with tritium. I. The distribution and configuration of label in 3β‐hydroxy‐5α‐androstane‐17‐one (1)

Catalytic reduction of 3β‐hydroxyandrost‐4‐ene‐17‐one (I) with tritium gas gave a mixture of 3β‐hydroxy‐5α‐androstane‐17‐one (II) and 3β‐hydroxy‐5α‐androstane‐17‐one (III). Oxidation of compound II followed by alkaline equilibration resulted in 37% loss of label from position 4. 5α‐Androstane‐3,7‐dione (IVa) was converted via the 2,4‐dibromide to androst‐4‐ene‐3,7‐dione (VIIIa) with 43% loss of radioactivity from position 5. Chloranil dehydrogenation and alkaline equilibration experiments have shown that the additional label was at C‐6α. The distribution and configuration of label in compound II was found to be 37% 4α, 43% 5α and 20% 6α.