Theoretical Study of Reactivity and Stability of a Thiazine Derivative Series by the Density Functional Theory (DFT) Method

Abstract

The study of the reactivity and stability of the five (05) compounds of Thiazine was carried out using the density functional theory at the level B3LYP/6-31+ G (d, p). The determination of the dual descriptor as well as the analysis of the map of the molecular electrostatic potential (MEP) made it possible to show that the sulfur and nitrogen atoms of the Thiazine cycle are respectively the electrophilic and nucleophilic sites. The study of the chemical reactivity of our compounds was carried out from the analysis of the frontier molecular orbitals (HOMO and LUMO), the energy gap (ΔE), the chemical hardness (η), the electrophilicity index (ω) and electronegativity (χ). Thus, the Thz3 compound is the least reactive, the least electron donor and the most stable of all our compounds.