Abstract
The concept of polarity (nucleo- and electrophilicity) of free radicals in processes of addition to unsaturated substrates was developed within the framework of the method of qualitative potential energy surfaces on the basis of an analysis of the interaction of diabatic surfaces for reactions of free-radical addition to olefins. A formulation is given for the concept of the polarity (“philicity”) of the attacking free radical; the theoretical index of philicity and the criterion of polarity of the radicals are proposed; the concept of ambiphilicity of a radical is introduced. The chemical aspects of the philicity of free radicals — the influence of a change in it on the formation and height of the activation barrier of the reaction and the strength of the bond formed — are discussed. A parallel formulation of the concept of polarity of radicals in terms of boundary orbital interactions in the free-radical-unsaturated substrate system is given.
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Translated from Teoreticheskaya i Éxperimental'naya Khimiya, Vol. 22, No. 5, pp. 562–571, September–October, 1986.
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Volovik, S.V., Dyadyusha, G.G. & Staninets, V.I. Concept of polarity of free radicals in reactions of addition to olefins. Theor Exp Chem 22, 535–544 (1987). https://doi.org/10.1007/BF00522538
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DOI: https://doi.org/10.1007/BF00522538