Spin trapping by use of nitroso-compounds. Part IV. Electron spin resonance studies on oxidation with nickel peroxide

Abstract

The oxidation reactions of nickel peroxide were studied by use of nitrosobenzene and 2-methyl-2-nitrosopropane as spin traps. We have demonstrated by spin trapping with nitrosobenzene that nickel peroxide suspended in benzene oxidises aromatic hydrocarbons ArCHR₂ or Ar₂CHR to benzylic radicals, that radicals can similarly be formed from many compounds containing active methylene groups, and that nitroxide radicals can also be obtained from many phenols and amines. A molecule-induced homolysis occurs in the reaction of a nitroso-compound with a hydroperoxide which may be contained as an impurity in a substrate. Relationships between spectral data and structures of nitroxides formed are also discussed.