The Vitamin D Potency of Egg Yolk from Irradiated Hens.

(1) If heated with iodine as a catalyst, the tertiary alcohol (I) readily yielded the olefin (III). (2) This olefin rearranged immediately to the dicyclic hydrocarbon (II) when digested with concentrated sulfuric acid. (3) Treated with the proper concentration of sulfuric acid, or phosphoric acid, the alcohol (I) passed immediately to the olefin (III), which on longer treatment changed to the ionene homolog (II). Hence, either (III) or (II) was obtained, depending upon the duration of the treatment. These reactions are now being extended and applied in manifold directions, for the synthesis of numerous polyeyelic hydrocarbons and of derivatives not readily accessible by other methods.