Spectroscopic, DFT studies and electronic properties of novel functionalized bis-1,3,4-thiadiazoles

Abstract

We report the characterization of novel derivatives of bis-1,3,4-thiadiazoles. The investigated derivatives were characterized using UV‒Vis and FTIR spectroscopic techniques. In addition to spectroscopic analyses, DFT calculations were utilized to predict the chemical and drug-like properties of the compounds under investigation. According to the obtained results, the bis-1,3,4-thiadiazole derivatives under study were found to have high electrophilicity indices (> 2.5). Moreover, the experimentally investigated electronic transitions in the UV‒Vis region of the electromagnetic spectrum were studied by theoretical means through the visualization of HOMO and LUMO molecular orbitals (ΔE ~ 7 eV) and TDDFT calculations. It was found that the compounds maximally absorb the electromagnetic radiation at wavelengths of about 350 nm (in chloroform) in addition to some absorption shoulders which may be due to π‒π* and/or n‒π* electronic transitions. Electrostatic potential maps were used to visualize the sites of high and low electrostatic potential which give information about the possible sites of electrophilic and nucleophilic reactions.