Some reaction safety aspects of ruthenium-catalyzed allylic oxidations of Δ-5-steroids in the pilot plant

The ruthenium-catalyzed allylic oxidation of Delta-5-steroids with tert-butyl hydroperoxide to the corresponding unsaturated ketones was studied. During the scale-up to the pilot plant level, serious safety problems were detected, and the identified runaway potential of this reaction was studied. By modifying the original oxidation procedure, it was possible to establish this reaction safely in the pilot plant at 17-kg scale. Furthermore, the procedure was applied successfully to several other steroids on the laboratory scale.