Browsing by Author "Demir Atlı D."

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    Dinuclear N-heterocyclic carbene silver complexes: Synthesis, luminescence and catalytic studies
    (Elsevier B.V., 2019) Demir Atlı D.; Gülle S.
    A new dibenzimidazole compound (1) and three dibenzimidazolium salts (2a-2c) were prepared. Reactions of these salts with silver(I) oxide in methanol led to dinuclear N-heterocyclic carbene silver complexes (3a-3c). All of the compounds were characterized by 1H NMR, 13C NMR and elemental analyses. Molecular weights of the silver complexes were confirmed by MALDI-TOF mass spectrometry. Preliminary catalytic studies using all the silver complexes were performed on three-component coupling reaction of p-formaldehyde, piperidine and phenylacetylene. Complexes 3a and 3c exhibited good catalytic activities under neat conditions. The silver complexes showed luminescence properties in CH3CN at room temperature. © 2018 Elsevier B.V.
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    Air stable N-heterocyclic carbene silver complexes: synthesis, characterization, and antibacterial activity
    (Taylor and Francis Ltd., 2023) Demir Atlı D.; Aksu D.
    A new benzimidazolium salt containing a 2,5-dimethylbenzyl substituent and six N-heterocyclic carbene (NHC) silver complexes were prepared. The complexes were characterized by NMR, FTIR, and LC-MS spectroscopic methods and elemental analyses. They are stable in solution for a week. The antibacterial properties of the Ag(I) complexes against two Gram-positive and two Gram-negative bacteria were investigated. Inhibition zone and minimum inhibitory concentration (MIC) data establish that these NHC-Ag(I) complexes possess antibacterial activities; 2b showed the highest antibacterial activity overall against Gram-positive and Gram-negative bacteria. © 2023 Informa UK Limited, trading as Taylor & Francis Group.
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    Synthesis, characterization, and antibacterial properties of novel N-heterocyclic carbene (NHC) precursors and their silver complexes
    (Springer, 2025) Demir Atlı D.; Avcı Özbek H.; Aksu D.
    In this work, a new compound, 1-(3,5-dimethoxybenzyl)-5,6-dimethylbenzimidazole, was prepared by N-alkylation of 5,6-dimethylbenzimidazole with potassium hydroxide and 3,5-dimethoxybenzyl bromide in ethanol. Three 5,6-dimethylbenzimidazolium salts were obtained by quaternisation of 1-(3,5-dimethoxybenzyl)-5,6-dimethylbenzimidazole with 4-cyanobenzyl bromide, 4-tert-butylbenzyl bromide, and bromoethane, respectively. Deprotonation of these with silver oxide afforded NHC silver complexes in good yields. The formation of the compounds was validated by nuclear magnetic resonance, Fourier transform infrared spectroscopy, elemental analysis, and LC–MS/MS (only for the silver complexes) methods. The complexes were found to be stable against air and light by 1H NMR analysis of their solutions after one week. Experimental studies were carried out on the antibacterial properties of both benzimidazolium salts and NHC silver complexes against pathogenic strains of Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Enterobacter cloacae. Inhibition zone and minimum inhibitory concentration values were determined. On the basis of these data, it was concluded that all the compounds studied were antibacterial against all the bacterial chains tested, particularly Gram-positive bacteria. The MIC values indicate that the coordination of the NHC ligands to the Ag(I) ion leads to an increase in their antibacterial activity. Bromo[1-(3,5-dimethoxybenzyl)-3-(4-tert-butylbenzyl)-5,6-dimethylbenzimidazolin-2-ylidene]silver showed better activity against S. aureus than the standard antibiotic gentamicin. © Springer-Verlag GmbH Austria, part of Springer Nature 2025.