Application of Changes in Atomic Charges Resulting from Different Electrochemical Oxidation Mechanisms for the Estimation of the First Oxidation Potential of Flavonoids
Abstract
In addition to our model based on the sum of the differences in the net atomic charges between a cation and a neutral flavonoid (\(\sum_{s(C)} \Delta NAC_{\text{Cat-Neut}}\)) over the carbon atoms in the flavonoid skeleton, here I present two complementary
models for the estimation of the first electrochemical oxidation potential, \(E_{p1}\). The models were also based on the sum of differences in the net atomic charges, but between other species of a flavonoid; between a radical and an
anion of a flavonoid, \(\sum_{s(C)} \Delta NAC_{\text{Rad-Anion}}\), and between a radical and a neutral flavonoid, \(\sum_{s(C)} \Delta NAC_{\text{Rad-Neut}}\). These three variables are connected with different mechanisms (SET-PT, SPLET
and HAT) of electron loss during the electrochemical oxidation of a flavonoid. It was shown that the best model for the given set of 29 flavonoids was obtained by using mean values of all of the three variables as a variable (\(R^2 = 0.974,
S.E. = 0.042\) and \(S.E._{cv} = 0.45\)) which could mean that all three mechanisms are equally possible.
