Steroids. 12. Aromatization experiments in the progesterone series.

Aromatization experiments in the progesterone series are presented. Mineral oil vapor phase aromatization was employed in converting 1416- pregnatriene-320-dione prepared from allopregnane-320-dione into 3-hydroxy-17-acetyl-13516-estratetraene. Reactions discussed included its transformation into the aromatic analogs of the corpus luteum hormone progesterone and the adrenal hormone 17alpha-hydroxyprogesterone. Progesterone or 16-dehydroprogesterone on tri- or dibromination respectively followed by collidine dehydrobromination lead to the same 14616-pregnatetraene-320-dione which undergoes the dienone-phenol rearrangement. Hydrogenation of the rearrangement product yields the aromatic progesterone analog 1-methyl-3 -hydroxy-17-acetyl-135-estratriene.