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Öğe Active ruthenium(II)-NHC complexes for alkylation of amines with alcohols using solvent-free conditions(Pergamon-Elsevier Science Ltd, 2020) Yigit, Beyhan; Karaca, Emine Ozge; Yigit, Murat; Gurbuz, Nevin; Arslan, Hakan; Ozdemir, IsmailA series of new ruthenium(II) complexes bearing N-heterocyclic carbene ligands with benzylic groups were prepared by transmetallation reactions between silver(I) N-heterocyclic carbene complexes and [RuCl2(P-cymene)](2). All of the obtained complexes were characterized by FT-IR, H-1 NMR and C-13 NMR spectroscopy, and the molecular structure of compound 3c was also determined by X-ray crystallography. These ruthenium complexes were tested for the alkylation of aromatic amines with a wide range of primary alcohols under solvent-free conditions using the hydrogen borrowing strategy. All of the compounds tested here showed excellent catalytic activity for these reactions and N-monoalkylated products were obtained selectively using 2.5 mol% of the ruthenium complexes. (C) 2019 Elsevier Ltd. All rights reserved.Öğe The catalytic activity of new iridium(I) N-heterocyclic carbene complexes for hydrogen transfer reaction of ketones(Springer Wien, 2021) Karaca, Emine OzgeIn this paper, the reaction of [Ir(COD)Cl](2) with in situ prepared Ag-N-heterocyclic carbene (NHC) complexes yields a series of [IrCl(COD)(NHC)] complexes. All compounds were fully characterized by H-1 NMR, C-13 NMR, and FT-IR spectroscopy. The manuscript focused on the preparation of new Ir-NHC complexes, characterization and catalytic behavior. A series of hydrogenation transfer reactions were performed to reveal the effects of the Ir-NHC complexes. The new Ir-NHC complexes of benzimidazole-2-ylidene are effective catalysts for the transfer of hydrogenation of different ketones, using i-PrOH as the source of hydrogen in the presence of KOH. The reactions were conducted at a substrate/catalyst/base (S/C/base) molar ratio of 1:0.001:2. Although all of the complexes are active catalysts for the transfer hydrogenation of ketones, moderate yields were obtained with acetylnaphthalene and conversion was not observed with very substituted ketones such as 2 ',3 ',4 ',5 ',6 '-pentamethylacetophenone. It was observed that for transfer hydrogenation reactions Ir-NHC catalysts were more active, compared to Ru-NHC catalyzed studies performed by our team. Graphic abstractÖğe Catalytic activity of Ru/tetrahydropyrimidinium salts system for transfer hydrogenation reactions(Wiley-Blackwell, 2015) Karaca, Emine Ozge; Gurbuz, Nevin; Arslan, Hakan; VanDerveer, Don; Ozdemir, IsmailNew 1,3-dialkyltetrahydropyrimidinium salts as NHC precursors have been synthesized and characterized. The in situ prepared three-component 1,3-dialkyltetrahydropyrimidinium salts/[RuCl2(p-cymene)](2) and KOH catalyzes quantitatively the transfer hydrogenation of ketones under mild reaction conditions in 2-propanol. Also, the molecular structure of 1,3-bis(2-methylbenzyl)-3,4,5,6-tetrahydropyrimidinium was determined using single-crystal X-ray diffraction. Ions of the title compound are linked by CH...Cl and OH...Cl hydrogen bonding interactions. The NCN bond angle (124.3(2)degrees) and CN bond lengths (1.316(3) and 1.314(3) angstrom) confirm the existence of strong resonance in this part of the molecule. Copyright (c) 2015 John Wiley & Sons, Ltd.Öğe Crystal structure, optical properties, spectroscopic characterization and density functional theory studies of a new rhodium (i)-imidazolidin-2-ylidene complexes: Synthesis, characterization and cytotoxic properties(Elsevier Science Sa, 2022) Karaca, Emine Ozge; Ciftci, Osman; Ozdemir, Ilknur; Karabiyik, Hande; Karabiyik, Hasan; Gurbuz, Nevin; Ozdemir, IsmailRhodium(I) complexes bearing imidazolidin-2-ylidene ligands have been widely used in catalytic chemistry, but there are very few reports of the biological properties of these type complexes. A series of [RhCl(COD)(NHC)] complexes were synthesized. The structures of all compounds were characterized by 1H NMR, 13C NMR, IR and elemental analysis techniques, which supported the proposed structures. The single-crystal structures of complexes 1a and 1c have been determined. Single-crystal X-ray diffraction analysis indicates that complexes 1a and 1c crystallize in the centrosymmetric space groups P n m a and I 1 2/a 1 of the orthorhombic and monoclinic systems respectively. The ground state geometry of these complexes was optimized using density functional theory (DFT) at mixed double zeta basis set, 6-31G(d) for H, C, N, O and Cl and LANL2DZ for Rh. The presence of the different functional groups and the nature of their vibrations were identified by the experimental and theoretical infrared spectra. The optical properties of the studied complex were determined experimentally using UV-visible and photoluminescence techniques in solid-state and theoretically using the TD-DFT method. Hirshfeld surface analysis employing 3D molecular surface contours and 2D fingerprint plots has been used to analyze intermolecular interactions present in the solid-state. The cytotoxic properties of the rhodium(I)-NHC complexes have been assessed in various human cancer lines, including cisplatin-sensitive and resistant cells. IC50 values of these four complexes were determined by the MTS-based assay on three human cancer cell lines; brain (SH-SY5Y), colon (HTC116), and liver (Hep 3B). Substances 1a-d showed 100% anticarcinogenic effect in cancer cell lines at 50 and 100 mu M.Öğe Metal-Free a Simple and Versatile N ? B Dative Bond Stabilized Boron-Based Catalysts for Transfer Hydrogenation of Aromatic Ketones(Springer, 2024) Soylemez, Rahime; Kilic, Ahmet; Karaca, Emine Ozge; Ozdemir, IsmailIn this study, novel boron-containing salen ligands (1 and 2) and their tetra-coordinated boron-based polymers (1a-b and 2a-b) containing N -> B coordination bonds were synthesized under suitable conditions. In the first step, the synthesis of boron-containing salen ligands (1 and 2) was carried out as a result of the reaction of 4-formyl phenylboronic acid with different primary amines. Then, the obtained boron-containing salen ligands (1 and 2) were reacted with pentaerythritol and different N-donor ligands, respectively, to synthesize tetra-coordinated polymers (1a-b and 2a-b) containing N -> B coordination bonds. Synthesized boron-containing salen ligands and corresponding tetra-coordinated polymers containing (N -> B) coordination bonds were characterized by melting point, elemental analysis, LC-MS/MS spectrometer, FT-IR, UV-Vis and NMR (H-1, C-13, and B-11) spectroscopy for illuminate of their structures. The use of synthesized boron-containing salen ligands (1 and 2) and their polymers (1a-b and 2a-b) containing N -> B coordination bonds as novel organocatalysts were tested for the transfer hydrogenation of various aromatic ketones under suitable conditions. Considering all the catalytic results, it was seen that salen ligands (1 and 2) and tetra-coordinated boron-based polymers (1a-b and 2a-b) containing N -> B coordination bonds to be suitable organocatalysts in the future for transfer hydrogenation with other boron compounds. [GRAPHICS]Öğe A novel ditopic ring-expanded N-heterocyclic carbene ligand-assisted Suzuki-Miyaura coupling reaction in aqueous media(Pergamon-Elsevier Science Ltd, 2017) Karaca, Emine Ozge; Akkoc, Mitat; Tahir, Muhammad Nawaz; Arici, Cengiz; Imik, Fatma; Gurbuz, Nevin; Yasar, SedatA series of seven-membered ditopic ring-expanded N-heterocyclic carbene (dre-NHC) precursors, bearing sterically demanding and electron-rich aryl groups, were synthesised in moderate yields via the reaction of 1,2,4,5-tetrakis(bromomethyl)benzene with the corresponding N,N'-diarylformamidines in the presence of K2CO3 in acetonitrile under an air atmosphere. All new compounds were characterised by HRMS, NMR spectroscopy, and microanalysis, as well as X-ray crystallography for compound lc. The development of an efficient catalytic system for the Suzuki-Miyaura coupling reaction of aryl chlorides with various boronic acids was also investigated using the in situ generated dre-NHC ligands. (C) 2017 Elsevier Ltd. All rights reserved.Öğe Novel ruthenium(II)-N-heterocyclic carbene complexes; synthesis, characterization and catalytic application(Elsevier Science Sa, 2015) Yasar, Sedat; Karaca, Emine Ozge; Sahin, Caglar; Ozdemir, Ismail; Sahin, Onur; Buyukgungor, OrhanThe synthesis of highly active ruthenium(II) catalyst based on N-heterocyclic carbene (NHC) bearing alkyl and aryl groups is reported. The complexes are easily handled in very good yields via synthesis of silver -NHC complexes and subsequent reaction with [RuCl2(p-cymene)](2) in dichloromethane (DCM) under N-2 condition. All new compounds were characterized by LC-MSMS, elemental analysis, NMR spectroscopy and X-ray diffraction. With the development of a more efficient catalytic system for transfer hydrogenation of aryl ketones and aldehydes in mind, the catalytic performance of the Ru-NHC complexes for transfer hydrogenation was investigated. (c) 2015 Elsevier B.V. All rights reserved.Öğe Palladium Complexes with Tetrahydropyrimidin-2-ylidene Ligands: Catalytic Activity for the Direct Arylation of Furan, Thiophene, and Thiazole Derivatives(Amer Chemical Soc, 2015) Karaca, Emine Ozge; Gurbuz, Nevin; Ozdemir, Ismail; Doucet, Henri; Sahin, Onur; Buyukgungor, Orhan; Cetinkaya, BekirThe synthesis and characterization of novel 1,3-benzyl-3,4,5,6-tetrahydropyrimidin-2-ylidene-based N-hetero-cyclic carbene palladium(II) complexes (1a-d) were described. The crystal structure of trans-dichlorobis[1,3-bis(4-methylbenzyl)-3,4,5,6-tetrahydropyrimidin-2-ylidend- palladium(II) was presented. Pd(II) complexes 1a-d were tested as catalysts in the direct C5 or C2 arylation of furans, thiophenes, and thiazoles, with various aryl bromides at 150 degrees C for 1 h. These complexes exhibited moderate to high catalytic activities under the given conditions.Öğe Pd-N-Heterocyclic carbene catalysed Suzuki-Miyaura coupling reactions in aqueous medium(Arkat Usa Inc, 2018) Karaca, Emine Ozge; Akkoc, Mitat; Yasar, Sedat; Ozdemir, IsmailA new series of methyl substituted imidazole-based N-heterocyclic carbene (NHC) palladium complexes (PdCl2(L-1)NHC(L-1 =pyridine) is reported. Structural definitions of Pd-PEPPSI complexes were determined by NMR spectroscopy, elemental analysis and LC-MS spectroscopy techniques. To evolve a more efficient catalytic system for electronically different aryl chloride substrates on the Suzuki cross-coupling reaction, complexes were used as pre-catalyst. Activity of palladium(II)-NHC complexes screened under mild reaction conditions in aqueous media. With this catalytic system, the reaction proceeded in moderate or good yields with low catalyst loading (0.1 mol%). [GRAPHICS] .Öğe Platinum (II) N-heterocyclic carbene complexes: Synthesis, characterization and cytotoxic properties(Wiley, 2019) Karaca, Emine Ozge; Ciftci, Osman; Ozdemir, Ilknur; Yakali, Gul; Aygun, Muhittin; Gurbuz, Nevin; Ozdemir, IsmailPlatinum (II) complexes bearing N-heterocyclic carbene (NHC) ligands have been widely used in catalytic chemistry, but there are very few reports of biological properties of this type of complexes. A series of [PtCl2(NHC)(PEt3)] complexes were synthesized. The structures of all compounds were characterized by H-1-NMR, C-13-NMR, IR and elemental analysis techniques, which supported the proposed structures. The single crystal structures of complexes 1a and 1e were determined. The title complexes show slightly distorted square-planar coordination around the platinum (II) metal center. The cytotoxic properties of the platinum (II)-NHC complexes have been assessed in various human cancer lines, including cisplatin-sensitive and resistant cells. IC50 values of these four complexes were determined by the MTS-based assay on three human cell lines-brain (SHSY5Y), colon (HTC116) and liver (HEP3B). These complexes have been highlighted cancer therapeutic agent with unique structures and functions.Öğe Reduction hydrogenation of imines by in situ generated rhodium NHC complexes(Elsevier, 2020) Karaca, Emine Ozge; Dusunceli, Serpil Demir; Gurbuz, Nevin; Ozdemir, IsmailIn this paper we examined the catalytic activity of in situ prepared bidentate azolium salt/[RhCl(COD)](2) catalyst system in the transfer hydrogenation of imines with i-propanol to the corresponding amine. The first in situ transfer hydrogenation of imines to amines is described using [RhCl(COD)](2) with bidentate azolium ligands. New bidentate azolium salts (1a-c, 2a-c) as NHC precursors have been synthesized and characterized. The in situ prepared three-component bidentate azolium salts (LHX)/[RhCl(COD)](2) and t-BuOK catalyzes quantitatively the transfer hydrogenation of imines under mild reaction conditions in i-propanol. The results show that bidentate benzimidazolium salts were observed to be more active in reducing imines. Moreover, the method is simple and effective against various imines. (C) 2020 Elsevier B.V. All rights reserved.Öğe Ru(II)-NHC catalysed N-Alkylation of amines with alcohols under solvent-free conditions(Elsevier Science Sa, 2021) Karaca, Emine Ozge; Dehimat, Zieneb Imene; Yasar, Sedat; Gurbuz, Nevin; Tebbani, Dahmane; Cetinkaya, Bekir; Ozdemir, IsmailThe reaction of [RuCl2(p-cymene)]2 with in situ prepared Ag-N-heterocyclic carbene (NHC) complexes yields a series of [RuCl2(p-cymene)(NHC)] complexes (2). All of the complexes have been characterised by elemental analysis, and 1H NMR and 13C NMR spectroscopies. These complexes have been tested for the N-alkylation of aromatic amines with arylmethyl alcohols under neat conditions in the presence of KOtBu at 120 ?C. Compounds (2) are stable and have high catalytic/selective activity for the N-alkylation reactions of primary amines to afford secondary amines.Öğe Ruthenium(II)-NHC-catalyzed (NHC = perhydrobenzimidazol-2-ylidene) alkylation of amines using the hydrogen borrowing methodology under solvent-free conditions(Springer, 2019) Yigit, Murat; Karaca, Emine Ozge; Yigit, Beyhan; Gurbuz, Nevin; Ozdemir, IsmailNew ruthenium(II) complexes with N-heterocyclic carbene ligand were synthesized by transmetalation reactions between silver(I) N-heterocyclic carbene complexes and [RuCl2(p-cymene)](2). The complexes were characterized by physicochemical and spectroscopic methods. These ruthenium complexes were applied to the N-monoalkylation of aromatic amines with a wide range of primary alcohols under solvent-free conditions using the hydrogen borrowing strategy. The catalytic reactions using all ruthenium complexes resulted in N-monoalkylated products with high selectivities using furfuryl alcohol as the alkylating agent.Öğe Synthesis of 1,3-Disubtitituted Tetrahydropyrimidinium Salts and Determination of Their Biological Properties and Molecular Docking(Wiley-V C H Verlag Gmbh, 2024) Karaca, Emine Ozge; Gurbuz, Nevin; Demir, Yeliz; Tuzun, Burak; Ozdemir, Ismail; Gulcin, IlhamiSeveral of 3,4,5,6-tetrahydropyrimidinium salts with 1-methyl functionalization are produced. By using techniques for 1H-NMR, 13C-NMR, and IR spectroscopy, all compounds were investigated. Additionally, these compounds' abilities to block enzymes were looked into. They had a highly effective inhibitory effect on the isoenzymes of carbonic anhydrases I and II, butyrylcholinesterase (BChE), and acetylcholinesterase (AChE). Ki values were found in the range of 57.43 +/- 7.09-170.09 +/- 50.91 nM for AChE, 7.19 +/- 0.42-69.08 +/- 2.44 nM for BChE, and 46.48 +/- 5.74-203.38 +/- 46.15 nM for hCA I, and 30.19 +/- 4.03-171.96 +/- 30.27 nM for hCA II. As a result, 1,3-disubtitituted tetrahydroprimidinium salts exhibited potent inhibition profiles toward indicated metabolic enzymes. One of the most important methods for designing and creating novel, potent medications to treat Alzheimer's disease (AD) worldwide is the synthesis and discovery of new AChE and BChE inhibitors. The activities of synthesized 3,4,5,6-tetrahydropyrimidinium salts were compared against various proteins that are crystal structure of AChE (PDB ID: 4 M0E), crystal structure of BChE (PDB ID: 5NN0), crystal structure of hCA I (PDB ID: 2CAB), and crystal structure of hCA II (PDB ID: 3DC3), and then the drug properties of these molecules were examined. In this study, we have designed and synthesized a series of 1,3-disubtitituted tetrahydropyrimidinium salts were synthesized and characterized by IR and NMR spectra. These compounds were evaluated against the AChE, BChE, hCA I and hCA II enzymes. These compounds showed good enzyme inhibition profiles. The activities of the investigated 1,3-disubstituted tetrahydropyrimidinium salts were compared to the theoretical calculations results using molecular docking. imageÖğe Synthesis of New Schiff Base Compounds and Identification of Their Structures(Gazi Univ, 2018) Karaca, Emine OzgeSchiff base compounds are stable, readily synthesizable compounds. Besides, in many fields of chemistry having a wide use field in, industry, medicine and pharmacy has increased the interest in these compounds and made them widely available in different fields. Within the scope of the study, three new Schiff base compounds have been synthesized which can be dissolved in water. Schiff base compound by reacting nitrogen-containing aromatic aldehydes with ethylene diamine in ethanol; 1,2-bis[1-methylindole-3-carboxylidenamino] ethane (1a), 1,2-bis[p-diethylaminobenzylideneamino]ethane (1b), 1,2-bis[pdi(oxobutyl)aminobenzilidenamino] ethane (1c) synthesized and characterized by H-1, C-13 NMR spectroscopy, FT-IR and elementel analysis techniques. When FT-IR and NMR analysis results of the synthesized compounds were examined, the presence of characteristic peaks proving the formation of imine was observed and the synthesis of the compounds was successful.Öğe Synthesis of palladium complexes derived from imidazolidin-2-ylidene ligands and used for catalytic amination reactions(Wiley, 2016) Karaca, Emine Ozge; Gurbuz, Nevin; Sahin, Onur; Buyukgungor, Orhan; Ozdemir, IsmailN-Aryl amination and the Buchwald-Hartwig reaction are of great synthetic and industrial interest and scientists accept their usefulness and versatility for obtaining arylamines. In this study Ag-N-heterocyclic carbene complexes were used as trans-metallation reagents for the synthesis of Pd-N-heterocyclic carbene complexes. The new Pd-N-heterocyclic carbene complexes were characterized using elemental analysis and H-1 NMR, C-13 NMR and infrared spectroscopies. The crystal structure of one, namely dichlorobis[1,3-bis(2-methylbenzyl)imidazolidin-2-yliden]palladium(II), is presented. The activity of the Pd(II) complexes in the coupling reaction of anilines or amines with bromobenzene was investigated. These complexes exhibited high catalytic activities in the direct synthesis of triarylamines and secondary amines in a single step. Copyright (C) 2016 John Wiley & Sons, Ltd.Öğe Synthesis, crystal structure, DFT studies and catalytic activity of an N-(2,2-dimethyl-1,3-dioxolane-4yl-methyl)benzimidazole ruthenium(II) hydrate complex(Elsevier, 2023) Ozdemir, Namik; Karabekmez, Funda Dogan; Karaca, Emine Ozge; Gurbuz, Nevin; Ozdemir, IsmailIn this study, the new N-coordinated benzimidazole ruthenium(II) complex was synthesized. The complex was fully characterized by FT-IR, 1 H and 13 C NMR spectroscopic methods. The molecular structure of the complex has been verified by X-ray crystallography. Besides, theoretical structure and spectroscopic data were obtained using density functional theory (DFT/HSEH1PBE) method with the cc-pVDZ basis set for C, H, N, O and Cl atoms, and the LANL2DZ basis set for the metal atom, and compared with the experimental data. This complex has also been tested for the N-alkylation of aromatic amines with arylmethyl alcohols under neat conditions in the presence of KOBut.(c) 2023 Elsevier B.V. All rights reserved.
