Abstract
The experimental data on the relative reactivity of active methyl groups in a given molecule for various pyridines, pyrimidines, and their N-oxide and oxo derivatives were compared with the charge transfer ability (CTA) values calculated by the CNDO/2 method. The reactivity of active methyl groups of these compounds was examined in nitrosation and deuterium exchange reactions, and the CTA values were calculated in the deprotonation step of these reactions. The calculated values were in good accord with the experimental results. In particular, the experimental values for the N-oxides could be well interpreted in terms of the CTA values only when the calculations were performed in the conformation in which a 1 : 1 complex of sodium ion with the N-oxides was formed.
