Effect of the electronic structure of the heteroatom on the basicities of heterocyclic compounds

The proton-acceptor capacities of heterocyclic nitrogen compounds (pyridine, pyrazine, pyrimidine, and some of their derivatives) were subjected to a theoretical study by means of the molecular electrostatic-potential method. The wave functions of the examined compounds were obtained by the INDO method. It was found that the difference in the proton-acceptor capacities of the examined compounds is due to the difference in the electronic structures of the unshared pairs of the most basic atoms in these compounds.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1079–1083, August, 1981.