ABSTRACT The results of the experimental determinations of the Bond Dissociation Enthalpy values for the O-H bond on phenolic antioxidants, by means of an EPR equilibration technique, are presented. These are believed to be fairly accurate because of the logarithmic relation connecting the BDE’s to the measured equilibrium constants. Additive contributions for the various substitutents in the ortho, meta and para positions have been derived by using a multivariable minimization procedure. The additivity rule provides very good estimates of the BDE values of polysubstituted phenols, and can also be used for predicting O-H bond strength in those cases where the experimental values are not available.
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