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Öğe Bioactive NHC-derived palladium complexes: synthesis, catalytic activity for the Suzuki-Miyaura coupling of aryl chlorides and bromides and their antibacterial activities(Taylor & Francis Ltd, 2019) Boubakri, Lamia; Al-Ayed, Abdullah S.; Mansour, L.; Abutaha, Nael; Harrath, Abdel Halim; Ozdemir, I; Yasar, S.Pd(II)-bis(NHC) complexes (where NHC = N-heterocyclic carbene) bearing asymmetrically and symmetrically substituted NHC-ligand have been synthesized via deprotonation of 5,6-dimethylbenzimidazolium salts. The NHC precursors have been achieved via the two step N-alkylation of 5,6-dimethylbenzimidazole. The resultant salts were deprotonated with PdCl2 and K2CO3 in dry THF for 2(a-e). The obtained complexes were identified and characterized by H-1 and C-13 NMR, FT-IR, DART-TOF mass spectrometry and elemental analysis. These new Pd(II)-bis(NHC) complexes were applied as catalyst precursors for Suzuki-Miyaura cross-coupling reactions of aryl bromides and chlorides with phenylboronic acid to afford the corresponding products in good yields. This catalytic reaction was evaluated in the presence of KOtBu/toluene. The antibacterial activities of 2(a-e) were investigated against Gram (+)/(-) bacteria using the agar dilution procedure. The antibacterial activities of 2 vary with the nature of the ligands; MIC values of 2(a-e) were determined.Öğe Improved performance of the NaFePO4/Hardcarbon sodium-ion full cell(Pergamon-Elsevier Science Ltd, 2023) Altundag, S.; Altin, S.; Yasar, S.; Altin, E.Chronoamperometry and galvanostatic procedures were applied in the LiFePO4-based ion exchange approach for the production of NaFePO4 cathodes. The materials obtained by various processes were employed as the cathode electrode in Na-ion half cells, and their structural and electrochemical properties were investigated. According to XRD patterns for both processes, it is seen that the Na-ions were successfully replaced with Li-ions. In addition of this, XPS and EDX-dot mapping analyses were supports the ion exchange procedure. The electrochemical properties of the cathode were investigated using CR2032 cells, and the diffusion coefficient and diffusion activation energy were calculated using the CV graphs at various scan rates and environmental temperatures. It was found that the Na-diffusion rate in the cell is faster at higher temperatures than at lower temperatures. The galvanostatic cycling tests were performed for C/10 and 1C rates at room temperature, 10 degrees C, and 50 degrees C and determined that the first capacities for C/10 and 1C at room temperature were 140mAh/g and 60mAh/g, respectively, with good stability. The full cells of NaFePO4/hard carbon were fabricated by pre-sodiation tech-nique and the battery performance tests revealed that the cells have a 74 mAh/g for C/10-rate with a voltage window of 2-4 V.Öğe In situ palladium/N-heterocyclic carbene complex catalyzed carbonylative cross-coupling reactions of arylboronic acids with 2-bromopyridine under CO pressure: efficient synthesis of unsymmetrical arylpyridine ketones and their antimicrobial activities(Springer, 2019) Boubakri, L.; Al-Ayed, Abdullah S.; Mansour, L.; Harrath, A. A.; Al-Tamimi, J.; Ozdemir, I.; Yasar, S.The carbonylative Suzuki cross-coupling of 2-bromopyridine with various boronic acids to prepare unsymmetrical arylpyridine ketones has been carried out using palladium/N-heterocyclic carbene complexes as catalysts prepared in situ. The selectivity and the rate of these reactions are highly dependent on the conditions, i.e., nature of the palladium catalyst precursor, solvent, temperature and CO pressure. The main side-products arise from direct, non-carbonylative cross-coupling. Under the optimum conditions, arylpyridine ketones are recovered in high yields (60-88%). The antibacterial activities of the corresponding benzimidazole salts 2 were tested against Gram positive and negative bacteria using the agar dilution procedure, and their IC50 values have been determined.Öğe N-Heterocyclic carbene-Pd(II)-PPh3 complexes as a new highly efficient catalyst system for the Sonogashira cross-coupling reaction: Synthesis, characterization and biological activities(Taylor & Francis Ltd, 2018) Boubakri, L.; Mansour, L.; Harrath, A. H.; Ozdemir, I.; Yasar, S.; Hamdi, N.A novel series of N-heterocyclic carbene-phosphine palladium(II) complexes has been synthesized and fully characterized by IR, H-1 NMR, C-13 NMR, and P-31 NMR spectroscopies, and elemental analysis. The new N-heterocyclic carbene (NHC)-phosphine palladium(II) complexes 3a-h have been easily prepared by the reaction of the corresponding PEPPSI (pyridine-enhanced precatalyst preparation stabilization and initiation) complexes 2a-h and triphenylphosphine in dichloromethane in high yields. These complexes were applied as catalyst precursors which efficiently catalyzed Sonogashira reactions between aryl bromides and phenylacetylene to afford the corresponding products in good yields. The bulky NHC-Pd-PPh3 complexes 3 were tested against Gram-positive and Gram-negative bacteria to study their biological activity. All the complexes exhibit antibacterial against these organisms. Investigation of the antiacetylcholinesterase activity of the studied complexes showed that compounds 3a and 3b exhibited moderate activity at 100 mu g mL-1 and product 3b is the most active.Öğe The production of a low cost printing device for energy storage systems and the application for supercapacitors(Elsevier, 2019) Altin, S.; Bulut, F.; Yasar, S.The miniature printing device was produced by using 3- axis stage and the stage was controlled by microprocessor. The ink section was fixed at the top of the stage and the substrate was mobile in the system. The ink was produced by using graphene as an electrode material and it was printed on a non-conductive substrate. It was used a 1M KOH for an electrolyte material and electrochemical performance of the device were investigated. It was obtained that the first cycle specific capacity of the device is 102 F/g and it was decreased to 88 F/g for 1000 cycle. So it may say that the device is very useful for energy storage device and it is cheaper than that of the commercial systems.Öğe Substituted N-heterocyclic carbene PEPPSI-type palladium complexes with different N-coordinated ligands: Involvement in the direct C-H bond activation of heteroarenes derivatives with aryl bromide and their antimicrobial, anti-inflammatory and antioxidant activities(Elsevier Science Sa, 2022) Slimani, I; Boubakri, L.; Ozdemir, N.; Mansour, L.; Ozdemir, I; Gurbuz, N.; Yasar, S.In this study new benzimidazolium salt as N-heterocyclic carbene precursors and their related new PEPPSI-Pd (II)-N-heterocyclic carbene (NHC) complexes 3a-e were prepared and caracterized. The structures of all compounds have been characterized by H-1 NMR, C-13 NMR, and IR spectroscopy, as well as elemental analysis techniques and Direct analysis in real time (DART)-time-of-flight mass spectrometry (TOF-MS), which support the proposed structures. Further confirmations of structural details were provided by a single-crystal X-ray. A single crystal of PEPPSI-Pd(II)-N-heterocyclic carbene (NHC) complex 3c shows that the coordination geometry around Pd slightly distorted square-planar geometry. Next, the PEPPSI-Pd(II)-N-heterocyclic carbene (NHC) complexes 3a-e were used as catalysts in the direct C-5-arylation of 2-acetyl furan and 2-acetylthiophene with various aryl bromides. These complexes exhibited moderate to high catalytic activities and gave C-H activation selectively at the C-5-position. Further, PEPPSI-Pd(II)-N-heterocyclic carbene (NHC) complexes 3a-e have been evaluated for their potential antibacterial properties against a panel of bacterial strains namely, Micrococcus luteus, Listeria monocytogenes, Salmonella Typhimurium, Staphylococcus aureus, candida albican and pseudomonas aeruginosa. In addition; these new PEPPSI-Pd(II)-N-heterocyclic carbene (NHC) complexes 3a-e were investigated for anti-oxidant activities by super oxide radical; DPPH (2,2-Diphenyl-1-picrylhydrazyl); and hydroxyl radical scavenging assays; in which most of them displayed significant antioxidant activities. Furthermore; PEPPSI-Pd(II)-N-heterocyclic carbene (NHC) complexes 3a-e were evaluated for anti-inflammatory activity by indirect haemolytic and lipoxygenase inhibition assays and revealed good activity.Öğe Synthesis and catalytic applications of palladium N-heterocyclic carbene complexes as efficient pre-catalysts for Suzuki-Miyaura and Sonogashira coupling reactions(Royal Soc Chemistry, 2017) Boubakri, L.; Yasar, S.; Dorcet, V.; Roisnel, T.; Bruneau, C.; Hamdi, N.; Ozdemir, I.A new palladium complex series with N-heterocyclic carbene (NHC), pyridine and phosphine ligands, PdCl2(L)NHC (2a-c)(L = NHC), PdCl2(L-1)NHC(3a-c)(L-1 = pyridine), PdCl2(L-2)NHC(4a-c)(L-2 = triphenyl-phosphine) was synthesised and fully characterized. The catalytic activities of these complexes were screened for the Sonogashira and Suzuki-Miyaura reactions between arylhalides and phenylacetylene, and phenylboronic acid, respectively. The results pointed out that the carbene/phosphine complexes 4a-c exhibited excellent catalytic activities as compared to 2a-c, 3a-c, and the well-known systems for the palladium-catalysed Sonogashira reaction. The reactivity of 4a-c in these preliminary Sonogashira coupling tests seems to be higher than that of previously reported catalytic systems based on Pd(NHC) moieties. These new palladium NHC complexes are among the first reported palladium catalysts that are efficient for catalysing the Sonogashira reaction from arylchloride substrates.Öğe Synthesis of novel Ag(I)-N-heterocyclic carbene complexes soluble in both water and dichloromethane and their antimicrobial studies(Taylor & Francis Ltd, 2019) Boubakri, Lamia; Dridi, Khaireddine; Al-Ayed, Abdullah Sulaiman; Ozdemir, I.; Yasar, S.; Hamdi, NaceurThe interaction of the benzimidazolium salt with Ag2O in dichloromethane to prepare novel Ag(I)-N-heterocyclic carbene complexes has been carried out at room temperature for 48 h in the absence of light. The obtained complexes were identified and characterized by H-1 and C-13 NMR, FT-IR and elemental analysis techniques. In addition, it has been found that some of the complexes are antimicrobially active and show higher activity than the free ligand. Probably metal chelation affects significantly the antimicrobial behavior of the ligands. The minimum inhibitory concentration of the complexes was determined. The results indicated that these complexes exhibit antimicrobial activity.Öğe Synthesis, characterization, and transfer hydrogenation of Ru(II)-N-heterocyclic carbene complexes(Taylor & Francis Ltd, 2014) Yasar, S.; Cekirdek, S.; Ozdemir, I.A new series of ruthenium(II) N-heterocyclic carbene complexes [RuL1,2,3(p-cymene)Cl-2] (3a-c) (where L is a N-heterocyclic carbene), have been synthesized via transmetalation. The new ruthenium( II)-NHC complexes were applied to transfer hydrogenation of acetophenone derivatives and aldehydes using 2-propanol as a hydrogen source and KOH as a co-catalyst. The results show that the corresponding alcohols could be obtained in good yield with high catalyst activity (up to 100%) under mild conditions. [RuL1(p-cymene)Cl-2] (3a) is much more active than the other complexes in transfer hydrogenation. Reactions, catalyzed by 3a-c, showed the highest reaction rates and yields of alcohol when the substrates bear more electron-withdrawing substituents. All new compounds were characterized by IR, elemental analysis, LC-MS (ESI), and NMR spectroscopy.
