Etude structurale des composés organiques à transfert de charges: Approche expérimentale et modélisation moléculaire

Abstract

We explored in this study the crystal structure determination of single crystal of organic compounds with charges transfer that belongs to the family of thiazole derivates. These heterocyclic systems are of great importance due to their excellent biological activity and their nonlinear optical properties. We carried out a conformational analysis of the keto and enol forms of Z-3N(2-Ethoxyphenyl), 2-N’(2-Ethoxyphenyl) imino thiazolidin-4-one. The crystal structure of the keto form has been determined by X-ray diffraction. The compound crystallizes in the monoclinic system with space group P21/n and cell parameters: a = 9.4094(10), b = 9.3066(10), c = 20.960(2) Å, β=99.0375(10)°, V = 1812.7(3)Å3 and Z = 4. The structure has been refined to a final R = 0.05 for 2083 observed reflections. The molecule in crystal exhibits intermolecular hydrogen bond of type C–H…O, C–H…N and C–H…S. Ab initio calculations were also performed at Hartree–Fock and density functional theory levels. The full HF and DFT geometry optimization was carried out using 6-31G(d,p) basis set. The observed molecular structure is compared with that calculated by both HF and DFT methods. The optimized geometry of the title compound was found to be consistent structure determined by X-ray diffraction.