Preparation and spectroscopic characterization of iron(II) and copper(II) complexes of a functionalized crown ether

Synthesis, characterization, and antimicrobial activities of novel double-armed benzo-15-crown-5 and their sodium and potassium complexes

New aldehyde- and halogen- (Cl, Br, I) substituted double-armed benzo-15-crown-5 derivatives are synthesized by the reactions of 4′,5′-bis(bromomethyl)benzo-15-crown-5 with 5-chlorosalicylaldehyde, 5-bromosalicylaldehyde, or 5-iodosalicylaldehyde. The sodium and potassium complexes are obtained by reaction of crown ether with sodium perchlorate and potassium iodide, respectively. Novel Schiff base compounds containing three groups of benzo-15-crown-5 are obtained from the condensation of aldehydes with 4′-aminobenzo-15-crown-5. The structures of all compounds are elucidated by elemental analysis, 1H, 13C NMR, IR, and mass spectra. The antifungal and antibacterial effects of the synthesized ligands are evaluated against pathogenic microorganisms and show varying degrees of inhibitory effects against the growth of different pathogenic strains.

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A comparative study of experimental and theoretical results of conformations of oxovanadium(IV) complexes with 4-acyl pyrazolone ligands using DFT method

The optimized structures and electronic properties of the oxovanadium(IV) complexes containing 4-acyl pyrazolone ligands were calculated using density functional theory. The total energies of both the complexes were calculated e.g. syn and anti conformation of complex 1 and complex 2 with and without solvent. The calculated total energy for syn conformation was -10.162 keV, while total energy for anti conformation was -10.155 keV. Similarly, the calculated total energy for complex 2 with solvent was obtained -10.793 keV, while total energy for complex 2 without solvent was -10.158 keV. The total energy calculation shows that syn conformation is more stable in complex 1, while complex 2 is more stable in twisted geometry with solvent. In order to investigate the electronic properties of ligands and complexes, quantum chemical parameters, such as the highest occupied molecular orbital energy (HOMO), the lowest unoccupied molecular orbital energy (LUMO), and energy gap were calculated. The theoretically calculated data of the complexes are in good agreement with the data obtained by the single-crystal X-ray diffraction analysis.