Stable Phenoxy-radicals

The present review is devoted to an examination and analysis of published data on reactions leading to the formation of phenoxy-radicals, and the structures and properties of these radicals.
In the description of the methods of preparing phenoxy-radicals, we examine the interaction of sterically hindered phenols with organic peroxides and inorganic oxidising agents, the mechanism of the thermal decomposition of cyclohexadienones, the autoxidation of sterically hindered phenols, and also the action of γ-radiation and ultraviolet radiation on phenols.
In the section devoted to the properties of phenoxy-radicals, we discuss the influence of steric hindrance of the reactive centre, and also the degree of delocalisation of the unpaired electron, on the stability of the phenoxy-radicals.
The available published data on the chemical transformations of substituted phenoxy-radicals are reviewed. Their recombination, disproportionation, isomerisation, and reaction with oxygen and halogens are examined. The influence of the steric and polar properties of substituents on the kinetics and mechanism of the transfer of hydrogen from organic compounds to stable phenoxy-radicals is analysed. The bibliography contains 180 references.