Yazar "Kaloglu, Nazan" seçeneğine göre listele
Listeleniyor 1 - 20 / 22
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Benzimidazolium sulfonate ligand precursors and application in ruthenium-catalyzed aromatic amine alkylation with alcohols(Elsevier, 2016) Kaloglu, Nazan; Ozdemir, Ismail; Gurbuz, Nevin; Achard, Mathieu; Bruneau, ChristianNew benzimidazolium sulfonate salts have been prepared and fully characterized. They have been associated in situ with [RuCl2(p-cymene)](2) to generate efficient catalytic systems operating at 120 degrees C under neat conditions in the presence of potassium tert-butylate for selective N-alkylation of primary aromatic amines into secondary amines. (C) 2015 Elsevier B.V. All rights reserved.Öğe Direct C-H Bond Arylation of C2-Blocked Pyrrole with Aryl Halides Using Palladium(II)-N-Heterocyclic Carbene Catalysts(Wiley-V C H Verlag Gmbh, 2018) Kaloglu, Murat; Kaloglu, Nazan; Ozdemir, IsmailHerein we report synthesis of seven new palladium(II)-NHC complexes with the general formula [PdX2(NHC)(2)], (NHC=1,3-dialkylbenzimidazol-2-ylidene, X = Cl or Br). The structures of all the new compounds were characterized by (HNMR)-H-1, (CNMR)-C-13, FT-IR spectroscopy and elemental analysis techniques. The catalytic activities of palladium(II)-NHC complexes were tested in the direct C-H bond arylation of C2-blocked pyrrole with various aryl halides in presence of 1mol% catalyst loading at 120 degrees C for 1-16 h. Under the given conditions, palladium(II)-NHC complexes showed the good catalytic performance for the direct C-H bond arylation of C2-blocked pyrrole with aryl bromides, and with readily available and inexpensive aryl chlorides. In all cases, the C-H bond arylation regioselectively produced C5-arylated products in moderate to high yields.Öğe The first use of [PdBr2(imidazolidin-2-ylidene)(pyridine)] catalysts in the direct C-H bond arylation of C2-substituted furan and thiophene(Springer, 2021) Kaloglu, Murat; Kaloglu, Nazan; ozdemir, Namik; ozdemir, IsmailN-Heterocyclic carbene (NHC)-linked PEPPSI-type palladium complexes have recently been used in the direct C-H bond arylation of heteroarenes. However, in most of the published works, NHC ligands containing benzimidazole and imidazole ring have been used, but using NHC ligands containing saturated imidazoline ring is quite rare. Therefore, in this study, four new 1,3-disubstituted imidazolinium salts as NHC ligand precursors, and their four new PEPPSI-type palladium complexes were synthesized. The structures of all new compounds were fully characterized by different spectroscopic and analytical techniques. The more detailed structural characterization of one of the palladium complexes was determined by single-crystal X-ray diffraction study. The catalytic activities of all palladium complexes were evaluated in the direct C-H bond arylation of the 2-acetylfuran and 2-acetylthiophene with (hetero) aryl bromides and readily available and inexpensive aryl chlorides in presence of 1 mol% catalyst loading at 120 degrees C. Under the given conditions, (hetero)aryl halides were successfully applied as the arylating reagents to achieve the C5-arylated furans and thiophenes in acceptable to high yields. [GRAPHICS] .Öğe N-heterocyclic carbene based ruthenium complexes for selective ?-C(sp3)-H functionalization of N-fused saturated cyclic amines(Pergamon-Elsevier Science Ltd, 2019) Kaloglu, NazanHerein, a series of new ruthenium(II) complexes with the general molecular formula [RuCl2(arene)(NHC)], (arene = eta(6)-p-cymene, NHC = N-heterocyclic carbene) were synthesized from in situ prepared silver(I)-NHCs by the transmetallation method. These complexes were fully characterized by analytical and spectral methods. Ruthenium(11) complexes were tested as promising catalyst for selective B-C(sp(3))-H functionalization of N-methylpiperidine with various aldehydes through hydrogen transfers in presence of external acidic additive. These eco-friendly cross-dehydrogenative couplings enable the production of C(3)-alkylated N-methylpiperidine derivatives without enamines with only carbon dioxide and water as benign by-product. (C) 2019 Elsevier Ltd. All rights reserved.Öğe N-Heterocyclic carbene-palladium catalysts for the direct arylation of pyrrole derivatives with aryl chlorides(Beilstein-Institut, 2013) Ozdemir, Ismail; Gurbuz, Nevin; Kaloglu, Nazan; Dogan, Oznur; Kaloglu, Murat; Bruneau, Christian; Doucet, HenriNew Pd-NHC complexes have been synthesized and employed for palladium-catalyzed direct arylation of pyrrole derivatives by using electron-deficient aryl chlorides as coupling partners. The desired coupling products were obtained in moderate to good yields by using 1 mol % of these air-stable palladium complexes. This is an advantage compared to the procedures employing air-sensitive phosphines, which have been previously shown to promote the coupling of aryl chlorides with heteroarenes.Öğe Novel benzimidazol-2-ylidene carbene precursors and their silver(I) complexes: Potential antimicrobial agents(Pergamon-Elsevier Science Ltd, 2016) Kaloglu, Murat; Kaloglu, Nazan; Ozdemir, Ilknur; Gunal, Selami; Ozdemir, IsmailNovel benzimidazolium salts were synthesized as N-heterocyclic carbene (NHC) precursors, these NHC precursors were metallated with Ag2O in dichloromethane at room temperature to give novel silver (I)-NHC complexes. Structures of these benzimidazolium salts and silver(I)-NHC complexes were characterized on the basis of elemental analysis, H-1 NMR, C-13 NMR, IR and LC-MS spectroscopic techniques. A series of benzimidazolium salts and silver(I)-NHC complexes were tested against standard bacterial strains: Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and the fungal strains: Candida albicans and Candida tropicalis. The results showed that benzimidazolium salts inhibited the growth of all bacteria and fungi strains and all silver(I)-NHC complexes performed good activities against different microorganisms. (C) 2016 Elsevier Ltd. All rights reserved.Öğe Novel benzimidazolium salts and their silver complexes: Synthesis and antibacterial properties(Elsevier, 2012) Gunal, Selami; Kaloglu, Nazan; Ozdemir, Ilknur; Demir, Serpil; Ozdemir, IsmailA series of-unsymmetrical N,N-disubstituted benzimidazolium salts were synthesized as N-heterocyclic carbene (NHC) precursors. These compounds were used to synthesize of N-heterocyclic carbene silver(I) complexes. New compounds were characterized by NMR and IR spectroscopies and elemental analyses. The antibacterial activity of all the compounds was tested against Gram (+)/(-) and fungal strains using the agar dilution procedure. (C) 2012 Elsevier B.V. All rights reserved.Öğe Palladium-carbene catalyzed direct arylation of five-membered heteroaromatics(Elsevier, 2020) Kaloglu, Murat; Kaloglu, Nazan; Ylidirim, Ilkay; Ozdemir, Namik; Ozdemir, IsmailDue to the industrial importance of bi(hetero)arenes, the synthesis of these compounds by homogeneous Pd-catalyzed direct arylation is an important research topic in modern organic chemistry. In this study, PEPPSI-type, (PEPPSI = Pyridine Enhanced Precatalyst Preparation Stabilization and Initiation), new Pd-catalysts with N-heterocyclic carbene ligand were synthesized, and they were used as catalysts in the synthesis of bi(hetero)arenes by direct arylation process. The structures of Pd-carbene complexes were elucidated by different spectroscopic and analytical techniques such as NMR, FT-IR and elemental analysis. The more detailed structural characterization of one of the complexes was determined by single-crystal X-ray diffraction study. Pd-carbene complexes were used as effective catalysts in the direct arylation of five-membered heteroaromatics such as thiophene, furan and thiazole derivatives with (hetero)aryl bromides for 1 h, in the presence of 1 mol% of catalyst loading, and successful results were obtained. (C) 2020 Elsevier B.V. All rights reserved.Öğe Palladium-PEPPSI-NHC Complexes Bearing Imidazolidin-2-Ylidene Ligand: Efficient Precatalysts for the Direct C5-Arylation of N-Methylpyrrole-2-Carboxaldehyde(Springer, 2021) Kaloglu, Murat; Kaloglu, Nazan; Ozdemir, IsmailThe Pd-catalyzed direct arylation of pyrroles is an important research field for organic synthesis and catalysis chemistry. However, imidazolidin-2-ylidene based Pd-NHC complexes (NHC=N-heterocyclic carbene) have not yet been employed as catalysts for the direct C5 mono-arylation of C2-substituted N-methylpyrrole derivatives with aryl halides. Therefore, we now report the synthesis and characterization of new 1,3-bis(substituted benzyl) imidazolinium salts as carbene precursors, and their corresponding Pd-PEPPSI-NHC type complexes (PEPPSI=Pyridine Enhanced Precatalyst Preparation Stabilization and Initiation). The catalytic properties of these complexes have been evaluated in the direct C5 mono-arylation of N-methylpyrrole-2-carboxaldehyde with a wide variety of (hetero)aryl halides. This environmentally attractive procedure has also been found to be tolerant to a wide variety of functional groups on the aryl halides such as formyl, acetyl, nitrile, fluoro or trifluoromethyl, and good yields have been obtained in presence of 1 mol% catalyst loading at 120 degrees C. [GRAPHICS] .Öğe PEPPSI-Pd-NHC catalyzed Suzuki-Miyaura cross-coupling reactions in aqueous media(Pergamon-Elsevier Science Ltd, 2019) Kaloglu, Nazan; Ozdemir, IsmailA series of unsymmetrical 1,3-disubstituted benzimidazolium chlorides were synthesized as N-heterocyclic carbene (NHC) precursors. These compounds were used to synthesize of the PEPPSI-type palladium NHC complexes. The structures of all compounds were characterized by H-1 NMR, C-13 NMR, FT-IR spectroscopy and elemental analyses. The catalytic activity of the PEPPSI-type palladium-NHC complexes has been evaluated with respect to the Suzuki-Miyaura cross-coupling reactions of phenyl boronic acid with various aryl halides in aqueous media. (C) 2019 Elsevier Ltd. All rights reserved.Öğe Ruthenium(II)-(Arene)-N-Heterocyclic Carbene Complexes: Efficient and Selective Catalysts for the N-Alkylation of Aromatic Amines with Alcohols(Wiley-V C H Verlag Gmbh, 2019) Kaloglu, Nazan; Achard, Mathieu; Bruneau, Christian; Ozdemir, IsmailA series of unsymmetrical 1,3-disubstituted benzimidazolium chlorides were synthesized as N-heterocyclic carbene (NHC) precursors. These compounds were used for synthesis of the new ruthenium(II) complexes of the type [RuCl2(arene)(NHC)], (arene = eta(6)-p-cymene). The structures of all compounds were characterized by H-1 NMR, C-13 NMR and FT-IR spectroscopy techniques. The catalytic activity of the ruthenium complexes has been evaluated with respect to the mono-N-alkylation reactions of aromatic amines with various alcohol derivatives under solvent-free conditions at 120 degrees C using the borrowing hydrogen strategy.Öğe Ruthenium(n6,n1-arene-CH2-NHC) Catalysts for Direct Arylation of 2-Phenylpyridine with (Hetero)Aryl Chlorides in Water(Mdpi, 2018) Kaloglu, Nazan; Ozdemir, Ismail; Gurbuz, Nevin; Arslan, Hakan; Dixneuf, Pierre H.A series of new benzimidazolium halides were synthesized in good yields as unsymmetrical N-heterocyclic carbene (NHC) precursors containing the N-CH2-arene group. The benzimidazolium halides were readily converted into ruthenium(II)-NHC complexes with the general formula [RuCl2 (eta(6),eta(1)-arene-CH2-NHC)]. The structures of all new compounds were characterized by H-1 NMR (Nuclear Magnetic Resonance), C-13 NMR, FT-IR (Fourier Transform Infrared) spectroscopy and elemental analysis techniques. The single crystal structure of one benzimidazole ruthenium complex, 2b, was determined. The complex is best thought of as containing an octahedrally coordinated Ru center with the arene residue occupying three sites, the remaining sites being occupied by a (carbene)C-Ru bond and two Ru-Cl bonds. The catalytic activity of [RuCl2(eta(6),eta(1)-arene-CH2 -NHC)] complexes was evaluated in the direct (hetero)arylation of 2-phenylpyridine with (hetero)aryl chlorides in water as the nontoxic reaction medium. These results show that catalysts 2a and 2b were the best for monoarylation with simple phenyl and tolyl chlorides. For functional aryl chlorides, 2d, 2e, and 2c appeared to be the most efficient.Öğe Silver(I) N-heterocyclic carbene complexes: Synthesis, characterization and cytotoxic properties(Elsevier Science Sa, 2020) Gurbuz, Nevin; Kaloglu, Nazan; Kizrak, Umran; Ozdemir, Ilknur; Turkmen, Nese Basak; Ciftci, Osman; Ozdemir, IsmailIn this study, sulfonate functionalized N-heterocyclic carbene ligand precursors were obtained from the compounds 1-alkylbenzimidazole, 1,3-propane sultone, and 1,4-butane sultone. These NHC ligand precursors were metallated with Ag2O on moderate conditions to give novel silver-NHC complexes. All new compounds were characterized by by H-1 NMR, C-13 NMR, FT-IR and elemental analysis techniques. The cytotoxic properties of the silver(I) 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 MTT based assay on three human cell lines brain (SHSY5Y) and liver (HEP3B). These silver N-heterocyclic carbene complexes have been highlighted metal-based cancer therapeutic agents with unique structures and functions. These strategies provide exciting opportunities for discovering new types of metallodrugs. (C) 2020 Elsevier B.V. All rights reserved.Öğe Silver-N-Heterocyclic Carbene Complexes: Synthesis, Characterization, and Antimicrobial Properties(Wiley-V C H Verlag Gmbh, 2017) Kaloglu, Nazan; Kaloglu, Murat; Ozdemir, Ilknur; Gunal, Selami; Ozdemir, IsmailSix new silver complexes containing symmetrical N-heterocyclic carbene (NHC) ligands were synthesized by the reaction of azolium salts with Ag2O in CH2Cl2. These complexes were tested against Gram-negative bacterial strains (Escherichia coli and Pseudomonas aeruginosa), Grampositive bacterial strains (Enterococcus faecalis and Staphylococcus aureus), and fungal strains (Candida albicans and Candida tropicalis), and all tested complexes showed good activity against the different microorganisms.Öğe Synthesis and antimicrobial activity of bulky 3,5-di-tert-butyl substituent-containing silver-N-heterocyclic carbene complexes(Wiley, 2017) Kaloglu, Nazan; Ozdemir, Ilknur; Gunal, Selami; Ozdemir, IsmailA series of novel benzimidazolium bromides containing bulky 3,5-di-tert-butyl group were synthesized in high yields as N-heterocyclic carbene (NHC) ligands. These NHC ligands were metallated with Ag2O under moderate conditions to give novel silver-NHC complexes. The structures of all compounds were characterized using H-1 NMR, (CNMR)-C-13, infrared and elemental analysis techniques, which supported the proposed structures. The silver-NHC complexes were screened for their in vitro antimicrobial activities against the standard bacterial strains Enterococcus faecalis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa and the fungal strains Candida albicans and C. tropicalis. The results showed that most of the silver-NHC complexes inhibited the growth of all bacterial strains and fungal strains and were found to display effective antimicrobial activity against different microorganisms.Öğe Synthesis and antimicrobial activity of novel gold(I) N-heterocyclic carbene complexes(Springer Wien, 2013) Dogan, Oznur; Kaloglu, Nazan; Demir, Serpil; Ozdemir, Ilknur; Gunal, Selami; Ozdemir, IsmailBenzimidazolium salts and six anionic gold-NHC complexes (NHC = N,N'-dialkylbenzimidazol-2-ylidene) were prepared and characterized. Novel [Au(NHC)(2)]AuCl2-type complexes were prepared in good yields from silver-NHC complexes by treatment with [AuCl(PPh3)], following the commonly used silver carbene transfer route. All compounds were characterized using H-1 and C-13 NMR spectroscopy, elemental analysis, and IR. The gold complexes showed antimicrobial activity against Gram-positive/negative and fungal strains.Öğe Synthesis of N-heterocyclic carbene-based silver complexes and their antimicrobial properties against bacteria and fungi(Taylor & Francis Ltd, 2022) Kaloglu, Murat; Kaloglu, Nazan; Gunal, Selami; Ozdemir, IsmailN-Heterocyclic carbene-based silver complexes (Ag-NHCs) have been widely used as organometallic drug candidates in medicinal and pharmaceutical chemistry research due to their low toxicity. Due to the success of Ag-NHCs in biological applications, interest in the synthesis and applications of such compounds is increasing rapidly. Therefore, in this study, ten Ag-NHC complexes containing benzimidazol-2-ylidene ligand were synthesized and characterized by H-1 NMR, C-13 NMR, FT-IR spectroscopies and elemental analyses. The antimicrobial activity of Ag-NHCs was tested against some standard culture collections of Gram-negative, Gram-positive bacterial strains and fungal strains, which are the most frequently isolated among the society and hospital acquired infectious microorganisms as potential metallopharmaceutical agents. The Ag-NHC complexes showed effective antimicrobial activity against microorganisms with MIC values between 6.25 and 100 mu g/mL.Öğe Synthesis of N-heterocyclic carbene-palladium-PEPPSI complexes and their catalytic activity in the direct C-H bond activation(Elsevier Science Sa, 2018) Kaloglu, Nazan; Kaloglu, Murat; Tahir, Muhammad Nawaz; Arici, Cengiz; Bruneau, Christian; Doucet, Henri; Dixneuf, Pierre H.A series of benzimidazolium salts having their two nitrogen atoms substituted by bulky groups have been synthesized. The benzimidazolium salts were readily converted into the corresponding palladium-NHC-PEPPSI complexes with general formula [PdBr2(NHC) (Py)], (NHC = N-heterocyclic carbene; PEPPSI = pyridine-enhanced precatalyst preparation, stabilisation, and initiation). The structures of all new compounds were characterized by NMR, IR spectroscopy and microanalysis techniques, which support the proposed structures. The molecular structure of complex 2g was determined by singlecrystal X-ray diffraction study. Next, the palladium-NHC-PEPPSI complexes were used as catalysts in the direct C5-arylation of 1-methylpyrrole-2-carboxaldehyde by aryl halides. These complexes exhibited moderate to high catalytic activities and gave C-H activation selectively at the C5-position of 1methylpyrrole- 2-carboxaldehyde. Both electron-donating and electron-withdrawing substituents were well tolerated with catalytic systems based on these complexes, even non-activated aryl chlorides such as chlorobenzene or 4-chlorotoluene were coupled with pyrrole in moderate yields. (C) 2017 Elsevier B.V. All rights reserved.Öğe Synthesis of new iron-NHC complexes as catalysts for hydrosilylation reactions(Wiley, 2013) Demir, Serpil; Gokce, Yasemin; Kaloglu, Nazan; Sortais, Jean-Baptiste; Darcel, Christophe; Ozdemir, IsmailA series of new piano-stool iron(II) complexes comprising N-heterocyclic carbene ligands [Fe(Cp)(CO)2(NHC)]I (NHC = 1,3-disubstituted imidazolidin-2-ylidene) have been synthesized and analyzed by 1H NMR, 13C NMR, IR, elemental analysis and mass spectrometric techniques. These compounds were easily prepared from the reaction of disubstituted imidazolidin-2-ylidene with [FeI(Cp)(CO)2] in toluene at room temperature. These complexes were tested in the catalytic hydrosilylation reaction of aldehydes and ketones with phenylsilane in solvent-free conditions. After a basic hydrolysis step, the corresponding alcohols were obtained in good yields. Copyright (c) 2013 John Wiley & Sons, Ltd.Öğe Synthesis of ruthenium N-heterocyclic carbene complexes and their catalytic activity for ?-alkylation of tertiary cyclic amines(Elsevier Science Sa, 2015) Ozdemir, Ismail; Dusunceli, Serpil Demir; Kaloglu, Nazan; Achard, Mathieu; Bruneau, ChristianThe novel ruthenium N-Heterocyclic carbene complexes are synthesized, and characterized by studying its H-1, C-13, elemental analysis, and X-ray. These complexes have been reported as promising catalyst for beta C-H bond functionalization of tertiary cyclic amines through hydrogen autotransfers in the presence of external acidic additive. The new catalytic products were characterized by H-1 NMR, C-13 NMR spectroscopic methods. (C) 2015 Elsevier B.V. All rights reserved.
