RESUMEN
The 2-amino-2-imidazoline moiety is currently used not only in drugs, but also in insecticides, and fungicides. Ab initio calculations are performed to evaluate the molecular properties of the two tautomeric forms and the protonated form with extended basis sets ranging from 6-31G* to 6-311++G** at Hartree-Fock and density functional (BLYP and B3LYP) levels. Møller-Plesset perturbation is tested at the MP2/6-31G* level only. Optimized geometry structures, energies and thermochemical properties are generated. Basis set and correlation effects on geometries, tautomer equilibrium constant and protonation enthalpy are carefully analysed. Although observed for the isolated molecule, these results may be extrapolated to chemical and biochemical systems of interest.
Asunto(s)
Imidazoles/química , Fungicidas Industriales/química , Insecticidas/química , Protones , Relación Estructura-Actividad , TemperaturaRESUMEN
The structure of two 5-(1-aryl-4-piperazino)methyl-2-aminooxazolines were determined by X-ray crystallography. An amino form is preponderant in a free base whereas an imino form is preponderant in a salt. The molecular conformations were studied by molecular mechanics.