Abstract
Mechanism was investigated for the chromogenic reaction of testosterone (I) with sulfuric acid. Dication (II in Chart 1) produced at the primary stage of the reaction was transformed into the chromophoric χ-484 (XIIa in Chart 4) via its conjugate base (VIII in Chart 4) by acid-base catalyzed isomerization. The conjugate base of the χ-484 (XIIb), 17, 17-dimethyl-18-norandrosta-4, 6, 8 (14)-trien-3-one (XIb), was isolated in 40% yield in the reaction of the epoxide (V in Chart 2) with sulfuric acid. Sulfuric acid solution of the trienone (XIa, b) showed a maximum absorption at 484 nm (ε=42000). The pKa value of XIIa was also determined.
