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DOI: 10.1039/A701154G (Paper) Reference Section for: J. Chem. Soc., Perkin Trans. 1, 1997, 3101-3106

Remarkable dependence of the regioselectivity of free radical additions to 3-cinnamoyloxazolidin-2-ones on the stability of the intermediate adduct-radical, electrophilicity of the adding radicals and the conditions for their generation

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Vitali I. Tararov, Nikolai Yu. Kuznetzov, Vladimir I. Bakhmutov, Nikolai S. Ikonnikov, Yuri N. Bubnov, Victor N. Khrustalev, Tatiana F. Saveleva and Yuri N. Belokon

Abstract

Electrophilic (CCl3) and nucleophilic radicals (Pri) are found to add at 80 °C to the C[double bond, length half m-dash]C bond of 3-(E)-cinnamoyl-4-phenyloxazolidin-2-one 1a and 3-(E)-cinnamoyl-4-benzyloxazolidin-2-one 1b predominantly at the α-position of the bond. While for the CCl3 radical no product of β-addition has been found, for the Pri radical such a path constitutes up to 40% of the whole process at 80 °C. An interplay between the stability of the intermediate adduct radicals and the electrophilicity or nucleophilicity of the radicals undergoing addition are invoked to rationalize the observation. At a low temperature (–23 °C) β-addition of the Pri radical becomes the dominant process (up to 75%).

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