Dependence of the reactivity of five-membered aromatic heterocycles on their structure. 4. Proton affinity of N-aminoazoles

Proton affinity of the amino groups of 10 N-aminoazoles is calculated using the STO-3G basis set. The nature of the heterocyclic effect on proton affinity of the amino groups depends on its conformation which in turn is determined by the number of nitrogen atoms in the α-position. The accuracy of the proton affinity calculation can be raised considerably by taking into account the interaction of heteroatoms in the ring.