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Öğe 1,3-Bis(4-tert-butylbenzyl)-4,5-dihydroimidazolium chloride monohydrate(Int Union Crystallography, 2009) Arslan, Hakan; VanDerveer, Don; Yasar, Sedat; Ozdemir, Ismail; Cetinkaya, BekirIn the title compound, C25H35N2+center dot Cl-center dot H2O,the imidazolidine ring adopts a twisted conformation, with a pseudo-twofold axis passing through the N-C-N carbon and the opposite C-C bond. The N-C-N fragment of the imidazolidine ring shows some degree of both double- and single-bond character due to partial electron delocalization. One of the tert-butyl groups is disordered over two conformations with occupancies of 0.714 (8) and 0.286 (8). In the crystal, O-H center dot center dot center dot Cl and C-H center dot center dot center dot O hydrogen bonds help to establish the packing.Öğe 1-(2-Phenylbenzyl)-3-(2,4,6-trimethylbenzyl)imidazolidinium bromide(Wiley-Blackwell Publishing, Inc, 2009) Arslan, Hakan; VanDerveer, Don; Yasar, Sedat; Ozdemir, Smail; Cetinkaya, BekirIn the title salt, C(26)H(29)N(2)(+)center dot Br(-),which may serve as a precursor for N-heterocyclic carbenes, the imidazolidine ring adopts a twist conformation with a pseudo-twofold axis passing through the N-C-N carbon and the opposite C-C bond. The N-C-N bond angle [113.0 (4)degrees] and C-N bond lengths [1.313 (6) and 1.305 (6) angstrom] confirm the existence of strong resonance in this part of the molecule. In the crystal, a C-H center dot center dot center dot Br interaction is present. The dihedral angle between the biphenyl rings is 64.3 (2)degrees and the phenyl rings make angles of 76.6 (3) and 18.5 (3)degrees with the plane of the imidazolidine ring.Öğe Anticancer, antimicrobial and antiparasitical activities of copper(I) complexes based on N-heterocyclic carbene (NHC) ligands bearing aryl substituents(Taylor & Francis Ltd, 2020) Touj, Nedra; Al Nasr, Ibrahim S.; Koko, Waleed S.; Khan, Tariq A.; Ozdemir, Ismail; Yasar, Sedat; Mansour, LamjedNew benzimidazolium salts were synthesized as N-heterocyclic carbene precursors. These NHC precursors were metallated with Cu2O and CuI in acetone and water under reflux to give novel copper(I) complexes. The structures of these benzimidazolium salts and copper(I) complexes were characterized on the basis of elemental analysis, H-1 NMR, C-13 NMR, IR and LC-MS spectroscopic techniques. The (NHC)Cu(I) complexes 3-4 were tested against MCF7 and MDA-MB-231 cancer cells, Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA) and Candida albicans microorganisms, Leishmania major promastigotes and amastigotes, Toxoplasma gondii parasites and against Vero cell line in vitro. The synthesized copper NHC carbene complex 4b (1,3-bis(2,3,4,5,6-pentamdthylbenzyl)-2,3-dihydro-1H-benzo[d]imidazol-2-yl)copper(I) chloride) was the most active against MCF7 cancer cells (half growth Inhibition Concentrations (IC50) = 0.3 mu g mL(-1)), as well as the most potent antimicrobial against E. coli (inhibition zone (IZ) = 23.3 mm), MRSA (IZ = 25.5 mm) and C. albicans (IZ = 28.5 mm) besides its antileishmanial activities against L. major promastigotes and amastigotes (IC50 < 0.04 mu g mL(-1)). Compound 4c (1,3-bis(4-(tert-butyl)benzyl)-2,3-dihydro-1H-benzo[d]imida-zol-2-yl)copper(II) bromide) is the most potent anticancer against MDA-MB-231 cancer cells IC50 = 0.4 mu g mL(-1)). Compound 4e (5,6-dimethyl-1,3-bis(2,4,6-trimethylbenzyl)-2,3-dihydro-1H-benzo[d]imidazol-2-yl)copper(I) chloride) is the best suitable antitoxoplasmal drug candidate due to its SI of 16.5. These candidates need further study to identify mode of action and drug standardization.Öğe Benzylic imidazolidinium, 3,4,5,6-tetrahydropyrimidinium and benzimidazolium salts(Wiley-V C H Verlag Gmbh, 2008) Yasar, Sedat; Oezdemir, Ismail; Cetinkaya, Bekir; Renaud, Jean-Luc; Bruneau, ChristianImidazoliidinium, tetrahydropyrimidinium and benzimidazolium. salts were prepared. Upon reaction with tBuOK, they generate carbene ligands, which were associated in situ to [RuCp*(MeCN)(3)]PF6 to produce ruthenium catalysts that are active for the substitution of allylic substrates by dimethyl of the N-heterocyclic structures, as well as that of the benzyhc N-substituents, on the reactivity and regioselectivity were examined. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008).Öğe Biological Activities of NHC-Pd(II) Complexes Based on Benzimidazolylidene N-heterocyclic Carbene (NHC) Ligands Bearing Aryl Substituents(Mdpi, 2020) Al Nasr, Ibrahim; Touj, Nedra; Koko, Waleed; Khan, Tariq; Ozdemir, Ismail; Yasar, Sedat; Hamdi, NaceurN-heterocyclic carbene (NHC) precursors (2a-i), their pyridine-enhanced precatalyst preparation stabilization and initiation (PEPPSI)-themed palladium N-heterocyclic carbene complexes (3a-i) and palladium N-heterocyclic triphenylphosphines complexes (4a-i) were synthesized and characterized by elemental analysis and H-1 NMR, C-13 NMR, IR, and LC-MS spectroscopic techniques. The (NHC)Pd(II) complexes 3-4 were tested against MCF7 and MDA-MB-231 cancer cells, Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA), Candida albicans microorganisms, Leishmania major promastigotes and amastigotes, Toxoplasma gondii parasites, and Vero cells in vitro. The biological assays indicated that all compounds are highly active against cancer cells, with an IC50 < 1.5 mu g mL(-1). Eight compounds proved antibacterial and antileishmanial activities, while only three compounds had strong antifungal activities against C. albicans. In our conclusion, compounds 3 (b, f, g, and h) and 4b are the most suitable drug candidates for anticancer, antimicrobial, and antiparasitical.Öğe Boron-doped porous carbon material derived from ZIF-11: Investigation of cotton fabric supercapacitor and Li-ion battery performances(Wiley, 2022) Bugday, Nesrin; Altin, Serdar; Bulut, Fatih; Altin, Emine; Yasar, SedatNitrogen-doped porous carbon (NPC@ZIF-11) and boron-NPC (BNPC@ZIF-11) materials were synthesized by pyrolysis methods, and structural characterization of the compounds was carried out by scanning electron microscopy, transmission electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, Brunauer-Elmet-Teller technique, Raman spectroscopy, and inductively coupled plasma-mass spectrometry techniques. The ZIF-11 was converted to the NPC@ZIF11 by pyrolysis. BNPC@ZIF-11 was fabricated from NPC@ZIF-11 by pyrolysis in the presence of phenylboronic acid. The fabric supercapacitor, sandwich-type supercapacitor, and Li-ion battery performances of NPC@ZIF-11 and BNPC@ZIF-11 were investigated. The capacity of the Li-ion cell was found as 720 mAh g(-1) for the first cycle, and it was decreased to 250 mAh g(-1) after 100 cycles. The capacitance values of the cylindrical devices were 92 F g(-1) and 115.6 F g(-1), for C1 and C4000 in KOH electrolytes. The BNPC@ZIF-11 was used as an electrode material on cotton fabric, and the highest obtained capacitance was 72.8 mF for 0.1 mA, which is a promising result for wearable energy storage materials.Öğe C-H Bond activation of 2-isobutylthiazole at C5 position catalysed by Pd-N-heterocyclic carbene complexes(Elsevier Science Sa, 2021) Bugday, Nesrin; Khan, Siraj; Yasar, Sedat; Ozdemir, IsmailA highly efficient and effective protocol has been developed for the synthesis of C5-(hetero)arylated 2-isobutylthiazole derivatives. Four different palladium N-heterocyclic carbene (Pd-NHCs) complexes [Pd(mu-Cl)Cl(SIMes)](2) (2), (LCl2 Pd-SIMes) (3: L = PPh3; 4: L = Py; 5: L = 3-CHO-Py) were synthesized and used for the first time as a catalysts in direct C-H arylation reaction of 2-isobutylthiazole at C5 position. Utilizations of these catalytic systems, the arylation of 2-isobutylthiazole with substituted (hetero)aryl bromides efficiently proceeded at low catalyst loading (1 mol%) and without any additives such as PivOH under argon or aerobic conditions at 120 degrees C in a short time. Different substituted (hetero)aryl bromides, even some deactivated or highly sterically hindered (hetero)arylbromides, with a wide range of functional groups were successfully utilized under the optimum reaction conditions. In all cases, the C5 arylated 2-isobutylthiazoles were obtained in moderate to excellent yields. (C) 2021 Elsevier B.V. All rights reserved.Öğe Dichloride [1-(2,4,6-trimethylbenzyl)-3-(biphenyl-2-ylmethyl)-imidazolidin-2-ylidine (?6-hexamethylbenzene)]ruthenium(Tubitak Scientific & Technological Research Council Turkey, 2006) Arslan, Hakan; Van Derveer, Donald; Ozdemir, Ismail; Yasar, Sedat; Cetinkaya, BekirThe single crystal X-ray structure of the imidazolidin ruthenium complex, C38H46N2Cl2Ru, was determined. The complex is an orthorhombic space group Pbca with a = 17.3586(32) angstrom, b = 14.4447(27) angstrom, c = 27.4325(52) angstrom, and V = 6878.466(4) angstrom(3) with Z = 8 for D-calc = 1.357 g/cm(3). It exhibits the expected 3-legged piano stool geometry. There is one coordination bond of the ruthenium atom with the electrons of the eta(6)-hexamethylbenzene, 2 symmetrical Ru-Cl bonds, and one Ru-C bond involving the imidazole ring. The coordination around the ruthenium atom is 4-fold, which in this is case is pseudo-tetrahedral.Öğe Dichlorido[1-(2-methylbenzyl)-3-(?6-2,4,6-trimethylbenzyl)-1H-2,3-dihydrobenzimidazol-2-ylidene]ruthenium(II) dichloromethane solvate(Wiley-Blackwell, 2009) Arslan, Hakan; VanDerveer, Don; Yasar, Sedat; Ozdemir, Ismail; Cetinkaya, BekirThe title complex, [RuCl2(C25H26N2)]center dot CH2Cl2, is best thought of as containing an octahedrally coordinated Ru center with the arene occupying three sites. Two Ru-Cl bonds and one Ru-carbene bond complete the distorted octahedron. The carbene portion of the ligand is a benzimidazole ring. This ring is connected to the C6H2(CH3)(3) arene group by a CH2 bridge. This leads to a system with very little apparent strain. A dichloromethane solvent molecule completes the crystal structure. Further stabilization is accomplished via C-center dot center dot center dot N and C-H center dot center dot center dot Cl interactions.Öğe An efficient (NHC) Copper (I)-catalyst for azide-alkyne cycloaddition reactions for the synthesis of 1,2,3-trisubstituted triazoles: Click chemistry(Elsevier Science Sa, 2017) Touj, Nedra; Ozdemir, Ismail; Yasar, Sedat; Hamdi, NaceurIn this study a series of new benzimidazolium salts (2a-c) were synthesized from the reaction of 5,6-dimethyl-1-(alkylbenzyl)-1H-benzo[d] imidazole with various alkyl halides. These salts were used to synthesize cupper N-heterocyclic carbene (Cu-NHC) complexes 3-4. The obtained (NHC) Copper (I) complexes 3-4 were characterized by FT-IR, NMR (H-1 and C-13) spectroscopic methods, mass spectrometry (EI-MS and HRMS) and elemental analysis. These novel cupper complexes 3-4 were used as a catalyst for alkyne - azide cycloaddition (CuAAC) reaction. Several triazoles 7 have been synthesized. This catalytic system fulfils the requirements of click chemistry with its mild and convenient conditions, notably in water at room temperature with low catalyst loading and simple isolation with no purification step. (C) 2017 Elsevier B.V. All rights reserved.Öğe An efficient ligand-free method for the transfer hydrogenation of ketones and aldehydes catalyzed by different complexes(Tubitak Scientific & Technological Research Council Turkey, 2013) Yasar, Sedat; Cekirdek, Suzan; Akkus Tas, Nilay; Yildirim, Semiha; Ozdemir, IsmailA very efficient ligand-free method was developed for the transfer hydrogenation of ketones and aldehydes catalyzed by different metal complexes. With this catalytic system, the catalytic performance and catalytic stability of different Ir, Ru, and Pd complexes were more favorable than those of the previously reported systems for transfer hydrogenation. This ligand-free catalytic system showed good stability and excellent activity even with lower catalyst concentrations for the ketones and aldehydes tested.Öğe An Efficient Protocol for Palladium N-Heterocyclic Carbene-Catalysed Suzuki-Miyaura Reaction at room temperature(Wiley-V C H Verlag Gmbh, 2017) Akkoc, Mitat; Imik, Fatma; Yasar, Sedat; Dorcet, Vincent; Roisnel, Thiery; Bruneau, Christian; Ozdemir, IsmailThe palladium-N-heterocyclic carbene complexes have been synthesised from 1,3-bis-(N-alkyl) benzimidazolium salts and catalytic activity of complexes have been tested on Suzuki-Miyaura coupling reaction for aryl bromides with substituted arylboronic acids at room temperature in i-PrOH/water. Structural characterisation of palladium complex 2b was determined by x-ray crystallography. A convenient and effective protocol has been evolved that has several superior advantages, including very low catalyst loading, vide range of substrate tolerance, excellent yields, room temperature, totally green solvents, short reaction times, up to 59750 h(-1) TOF (Turn Over Frequency) value with aryl bromide substrates and very simple procedure.Öğe Electrical and photoelectrical characterization of organic-inorganic heterostructures based on Ru-N-heterocyclic carbene complexes(Elsevier Gmbh, 2018) Yasar, Sedat; Cekirdek, Suzan; Binbay, Nil Ertekin; Tombak, Ahmet; Ocak, Yusuf Selim; Arslan, Nevin; Baysal, Akin1,3-Bis(2-morpholinethyl)benzimidazoliumtrichlorido(eta(6)-p-cymene)-ruthenate(11), 2, was synthesized and characterized by NMR spectroscopy and micro analysis. The organic -inorganic heterojunctions were fabricated by using n-type Si wafer and a series of Ru-N-heterocyclic carbene complexes, 3-5, bearing sterically hindered aryl groups were documented for the first time. The thin films of the complexes are deposited on n-Si substrates using spin coating. Current-voltage (I-V) measurements of the devices in dark and illuminated environments were analyzed to determine electrical parameters of devices. Furthermore, the photoelectrical properties of the structures were investigated examined using I-V measurements under a solar simulator. Complexes 3 and 5 showed very low series resistance resulting in high rectification ratios which are promising results for the future electronic and photoelectronic applications. (C) 2017 Published by Elsevier GmbH.Öğe Evaluation of NMR Results of Newly Synthesized Platinum-Based N- Heterocyclic Carbene Complexes(Wiley, 2023) Aslan, Sumeyye; Yuce, Hande; Yasar, Sedat; Bugday, Nesrin; Turkmen, Nese Basak; Eke, Benay Can; Unuvar, Songul[Abstract Not Available]Öğe Experimental and quantum mechanical investigation on two N-heterocyclic carbene palladium complexes(Taylor & Francis Ltd, 2021) Ozdemir, Namik; Touj, Nedra; Yasar, Sedat; Hamdi, Naceur; Ozdemir, IsmailTwo palladium complexes bearing different ligands such as N-heterocyclic carbene (NHC), pyridine and phosphines were synthesized and characterized by FT-IR spectroscopy, X-ray crystallography and quantum-chemical computations. DFT calculations have been performed at HSEh1PBE/SDD level of theory. Intermolecular interactions have been studied through two-dimensional fingerprint plots based on Hirshfeld surface analysis. Structural parameters and spectroscopic properties of the complexes are well interpreted by DFT and TD-DFT calculations.Öğe Facile construction of a robust and recyclable laccase/metal-organic framework-808 with boosted stability for biodegradation of Reactive Blue 171 and Reactive Blue 198 from aqueous media(Elsevier, 2024) Bakar, Busra; Bugday, Nesrin; Birhanli, Emre; Boran, Filiz; Ulu, Ahmet; Yasar, Sedat; Yesilada, OzferLaccase enzyme sees application demand in many industries such as textile, food processing, wood processing, pharmaceutical, and chemical. However, it becomes difficult to maintain the enzymatic activity of laccase under harsh reaction conditions and even after several biocatalytic cycles. Therefore, suitably prescribed supports are crucial to ensure that the catalytic activity and reusability of the immobilized laccase are maintained at high levels. The present study highlights the development and dye decolorization application of an enzyme carrier matrix employing a Zr-based metal-organic framework (MOF), MOF-808, with hierarchical porosity for the immobilization of laccase from Trametes trogii . The immobilization efficiency for Lac/MOF-808 was found to be 70.83 +/- 1.98 %. Lac/MOF-808 exhibited optimal catalytic temperature at 60 degrees C, while the optimal catalytic pH was 4.5. Due to recoverable properties from the carrier matrix the recycle test was satisfactory for the Lac/MOF808, being reused 7 times without losses greater than 50 % of residual activity. Stored at 25 degrees C, Lac/MOF-808 retained 30 % of its activity during 4-weeks period. A kinetic study was carried out for Lac/MOF-808 monitoring the oxidation reaction of ABTS. The K-m value was 0.070 mM and the V-max was 87.7 mu mol min(-1) g(-1). Kinetic investigations, on the other hand, demonstrated a decrease in K m following immobilization, signifying a higher affinity for substrate. The Lac/MOF-808 maintained its decolorization efficiency even after eight reaction cycles, exhibiting a remarkable activity of 56.7 % and 77.2 % against Reactive Blue 171 and Reactive Blue 198, respectively. Hence, the described Lac/MOF-808 might be an ideal candidate for efficient dye decolorization applications.Öğe Heck and suzuki reactions of aryl halides catalyzed by 1,3-dialkylimidazolinium/palladium(Science Press, 2008) Yasar, Sedat; Oezdemir, Ismail; Cetinkaya, BekirNew, sterically demanding 1,3-dialkylimidazolinium salts used as N-heterocyclic carbene precursors were synthesized and characterized. These salts, combined with palladium acetate, provided active catalysts for Heck and suzuki cross-coupling of aryl chlorides and bromides under mild conditions.Öğe Heterogenization of homogeneous NHC-Pd-pyridine catalysts and investigation of their catalytic activities in Suzuki-Miyaura coupling reactions(Elsevier Science Sa, 2018) Boztepe, Cihangir; Kunkul, Asim; Yasar, Sedat; Gurbuz, NevinNew generation, novel, environmentally safe polymeric heterogeneous catalysts which included catalytically active NHC-Pd-pyridine complexes were prepared by radical polymerization of NHC-Pd-pyridine complexes with Acrylamide (AAm) and 2-acrylamido-2-methylpropane sulfonic acid (AMPS) monomers in the presence of N,N'-methylenebisacrylamide (MBA) crosslinker. Structural characterization of NHCPd-pyridine complexes was conducted by using NMR, FT-IR while the structural characterization of crosslinked polymeric catalyst systems was made by using FT-IR, SEM, SEM-EDX, TEM and TGA analysis techniques. The synthesized polymer-based NHC-Pd-pyridine catalysts showed good catalytic activity for Suzuki reaction of aryl bromides with phenylboronic acid in aqueous media. They exhibited good stability and they could be reused at least five times without remarkable loss of catalytic activity. (C) 2018 Elsevier B.V. All rights reserved.Öğe High-performance electrodes for Li-ion cell: Heteroatom-doped porous carbon/CoS structure and investigation of their structural and electrochemical properties(Wiley, 2022) Bugday, Nesrin; Altin, Emine; Altin, Serdar; Yasar, SedatAs an essential class of anode materials, the synthesis and characterization of CoS@ZIF-12-C composite anode materials are reported. The two-step synthesis of CoS nanoparticles embedded in N-doped porous carbon by using a metal-organic framework (MOF) as the template. After structural characterization of CoS@ZIF-12-C composite materials, the main phase was found as CoS with symmetry of P63mmc. Benefiting from the CoS embedded in porous carbon structure, the half Li-ion battery cell tests of CoS@ZIF-12-C composite materials were performed by a 2-electrode method using CR2032 cells, and the capacities of the cells were measured for 200 cycles using 300 mAg(-1) and 500 cycles using 1000 mAg(-1). The first discharge capacities of the cells for 1000 mAg(-1) were found as 458, 1178, and 815 mAhg(-1) for CoS@ZIF-12-C-T, T = 700, 800, and 900 degrees C, respectively. An unexpected capacity increase was observed for the CoS@ZIF-12-C-700 and CoS@ZIF-12-C-900 half cells during the cycling. Ex-situ x-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and cyclic voltammetry (CV) analysis were performed after cycling of the cells for explanations of the capacity increase. Ex-situ XRD analysis of these cells showed phase transitions from crystalline to amorphous type structure, and ex-situ FTIR proves the preservation of the CoS phase during the cycling. A redox reaction mechanism was suggested to explain the cells' battery performance by ex-situ XRD analysis.Öğe Highly Active Fe3O4@SBA-15@NHC-Pd Catalyst for Suzuki-Miyaura Cross-Coupling Reaction(Springer, 2022) Akkoc, Mitat; Bugday, Nesrin; Altin, Serdar; ozdemir, Ismail; Yasar, SedatA novel Pd-NHC functionalized magnetic Fe3O4@SBA-15@NHC-Pd was synthesized and used as an efficient heterogeneous catalyst in the Suzuki-Miyaura C-C bond formation reactions. The Fe3O4@SBA-15@NHC-Pd characterized by X-Ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive X-ray analysis (EDX), Thermogravimetric Analysis (TGA), Differential Thermal Analysis (DTA). The Inductively Coupled Plasma-Optical emission spectroscopy (ICP-OES) analysis was used to determine the exact amount of Pd (0.33 wt%) in Fe3O4@SBA-15@NHC-Pd. The TEM images of the catalyst showed the existence of palladium nanoparticles immobilized in the catalyst's structure, while no reducing agent was used. The NHC moieties in the catalyst structure could be stabilize Pd(0) nanoparticles prevents agglomeration. The magnetic catalyst was effectively used in the Suzuki-Miyaura cross-coupling reaction of substituted phenylboronic acid derivatives with (hetero)aryl bromides in the presence of a K2CO3 at room temperature in aqueous media and magnetic catalyst could be simply extracted from the reaction mixture by an external magnet. Different aryl bromides were converted to coupled-products in excellent yields with spectacular TOFs values (up to 1,960,339 h(-1)); in the presence of 1 mg of Fe3O4@SBA-15@NHC-Pd catalyst (contains 3.1 x 10(-6) mol% Pd) at room temperature in aqueous media. After reusability experiments, it is found that this catalyst was effectively used up to ten times in the reaction with almost consistent catalytic efficiency. A decrease in the activity of the 10th reused catalyst was found as 9%. Graphic Abstract
