Abstract
Abstract
The valence isomerism of a series of heterocyclic mesomeric betaines (HMBs) belonging to class 5, called pseudo-semi-conjugated HMBs, has been studied theoretically both the neutral and the protonated species. These HMBs are 1H-pyrazol-2-ium-4-olates and related compounds where the oxygen atom has been replaced by S, Se atoms, and an NH group. The main conclusion of the present work is that the ring/open valence tautomerism is possible both for neutral and protonated although it has never been observed experimentally.
Funder
Ministerio de Ciencia, Innovación y Universidades
Comunidad de Madrid
Consejo Superior de Investigaciones Cientificas
Publisher
Springer Science and Business Media LLC
Subject
Physical and Theoretical Chemistry,Condensed Matter Physics