Functional metallomacrocycles and their polymers .34. Catalytic oxygenation of cyclohexene by water-soluble polymer containing manganese phthalocyanine complex

The catalytic oxygenation of cyclohexene with a water-soluble polymer containing 2-acryloylamino-9,15,24-tri(t-butyl)phthalocyanatomanganese complex in the presence of oxygen atom transfer reagents was studied in the presence of a nitrogen base. The catalytic activity was changed by the kind of oxygen atom transfer reagent (hydrogen peroxide and sodium hypochlorite). The polymer catalyst produced oxidized forms in a high yield using sodium hypochlorite as oxygen atom transfer reagent. The inhibition of the oxygen evolution was observed in the decomposition reaction of hydrogen peroxide when cyclohexene was added to the solution. A mechanism involving formation of a Mn-oxo complex and oxygen transfer from a reactive Mn-oxo intermediate to cyclohexene was proposed for this reaction. The inhibition of oxygen evolution was considered to be oxygen transfer to cyclohexene from the Mn-oxo species. On the other hand, the oxygenation of cyclohexene preferentially proceeded with sodium hypochlorite because of no reaction with the second hypochlorite. Overall, the polymer catalyst showed activity as a catalyst for oxygenation of cyclohexene using sodium hypochlorite in aqueous solution.