Efficient synthesis of 7-keto-DHEA acetate

7-keto-dehydroisoandrosterone(DHEA) acetate was efficiently synthesized from dehydroisoandrosterone 3-acetate and tert-butylhydroperoxide catalyzed by chromium(Ⅵ) oxide.This allylic oxidation proceeded smoothly under the mild conditions.The yield was 85.2%,is 37.5% for using collins reagent.This novel allylic oxidation reagent avoided using reagent and large volume of solvent in traditional chromium(Ⅵ) complexes oxidation procedures,was more convenient,efficient.