EXPERIMENTAL AND THEORETICAL INVESTIGATION OF MOLECULAR STRUCTURE AND CHARGE TRANSFER WITHIN SOME 8-HYDROXYQUINOLINE DERIVATIVES

A serie of novel 8-hydroxyquinoline derivatives: 5-HHQ, 5-MHQ, 5-EHQ and 5-PHQ were synthesized and characterized by means of IR, 1H and 13C NMR spectroscopic analysis. The crystal structures of 5-EHQ and 5-PHQ were solved by X-ray diffraction measurements on single crystal, the two others on powder samples. The UV–Visible spectra of molecules were performed in acetonitrile and ethanol. Density Functional Theory (DFT) and Hartree Fock (HF) methods have been used to determine its optimized geometrical parameters. Theoretical calculations such as HOMO-LUMO energies in fundamental state, in acetonitrile and ethanol, electronic dipole moments and atomic charges distribution were carried out for the title molecules using DFT (B3LYP) method at 6-311G (d, p) set. The results give us some explanation on the molecular structures, the intra charge transfer, relationships between the number of carbons connected to 5-hydroxymethyl-8-hydroxyquinoline and the bioactivity of selected derivatives