Recycling of osmium catalyst in oxidative olefin cleavage: a chemoentrapment approach

A new chemoentrapment strategy for recycling osmium in the catalytic olefin cleavage reaction is reported. The new strategy utilizes KOH/i-PrOH to generate water-soluble Os(VI) species as a recyclable metal catalyst after the oxidative cleavage reaction. For the recycling of the catalyst, NaIO4–NaClO2 was found to be the best combination of secondary oxidants and acetonitrile–water was chosen as an optimal solvent for the best recycling results. The new method allows for an efficient recycling of osmium in the reactions involving mono- and di-substituted olefins with 1 mol % of OsO4 without any significant side reactions and loss of yield.