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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 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 Direct arylation of arene C-H bonds by cooperative action of NHCarbene-Ruthenium(II) catalyst and carbonate via proton abstraction mechanism(Amer Chemical Soc, 2008) Ozdemir, Ismail; Demir, Serpil; Cetinkaya, Bekir; Gourlaouen, Christophe; Maseras, Feliu; Bruneau, Christian; Dixneuf, Pierre H.Direct functionalization of sp(2) C-H bonds via ortho diarylation of 2-pyridyl benzene with arylbromides was achieved using ruthenium(II) catalysts containing a RuCl2(NHC) unit and generated from [RuCl2(arene)](2) and two types of NHC precursors, pyrimidinium and benzimidazolium salts, in the presence of Cs2CO3. DFT calculations from RuCl2(NHC)(2-pyridylbenzene) show that a proton abstraction mechanism, on cooperative actions of both the coordinated base and the Ru(II) center, is favoured via a 13.7 kcal mol(-1) exothermic process affording an orthometalated intermediate with a 2.009 angstrom Ru-C bond.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 Investigation of hybrid-capacitor properties of ruthenium complexes(Wiley-Hindawi, 2019) Altin, Serdar; Oz, Erdinc; Altundag, Sebahat; Bayri, Ali; Roisnel, Thierty; Dorcet, Vincent; Bruneau, ChristianRu complexes were successfully produced, and their structural properties were investigated using FTIR, Raman, and single crystal XRD patterns. The HOMO, LUMO, Eg, and electronic surface potential (ESP) values of the molecules were calculated by a Gaussian program. The complexes were used for producing hybrid capacitor cells as electrode materials. According to electrochemical analysis, complex 2 showed the best CV graph between -1 V and +1 V and had the highest current value and hysteresis area when compared with the other complexes. The performance analysis and the capacity fade of the cells were investigated. The first capacity values of the complexes were 57.5, 22.1, 16.9, and 0.0021 F/g for complexes 1, 2, 3, and 4, respectively. The capacitive mechanism of the cells as relates to molecular interactions was also investigated. We suggested that the ESP values of the molecules were directly related to the capacitive performance of the cells. In addition to this, the best cycling performance was obtained for complex 2, which has the lowest Eg value among the complexes. We speculate that the charged regions on the complex materials have a crucial role in the increasing the capacitance of the cells.Öğe Investigation of potential hybrid capacitor property of chelated N-Heterocyclic carbene Ruthenium(II) complex(Elsevier Science Sa, 2018) Akkoc, Mitat; Oz, Erdinc; Demirel, Serkan; Dorcet, Vincent; Roisnel, Thierry; Bayri, Ali; Bruneau, ChristianThe synthesis of chelated ruthenium(II) complex type Ru(eta(6)-HMB) (NHC) Cl (NHC = N-heterocyclic carbene, HMB = hexamethylbenzene) is presented. The ruthenium(II)-NHC complex 6 was obtained in good yield and was fully characterised by NMR spectroscopy, X-ray diffraction and HRMS analysis. Electrochemical analysis by cyclic voltammetry (CV) revealed reversible redox behaviour at the ruthenium centre in 6. DFT studies and the catalytic activity of complex 6 on transfer hydrogenation reaction of aryl ketones are also presented. The potential hybrid capacitor applications of Ru-NHC complex is discussed and reported firstly in the literature. It was found that the highest performance was found at 20.1 F/g, which is a promising result for energy storage applications. (c) 2018 Elsevier B.V. All rights reserved.Öğe N-Alkylation and N,C-Dialkylation of Amines with Alcohols in the Presence of Ruthenium Catalysts with Chelating N-Heterocyclic Carbene Ligands(Amer Chemical Soc, 2015) Sahin, Zeynel; Gurbuz, Nevin; Ozdemir, Ismail; Sahin, Onur; Buyukgungor, Orhan; Achard, Mathieu; Bruneau, ChristianA series of new benzimidazolium salts and ruthenium(II) complexes containing chelating N-heterocyclic carbenes (NHCs) functionalized with a benzylic group and an acetal group were prepared. All of the synthesized compounds were characterized by elemental analysis and NMR spectroscopy, and the molecular structures of 2c and 2d were determined by X-ray crystallography. All of the,complexes were tested in the alkylation of cyclic amine derivatives with alcohols and showed excellent activity in this reaction. Cyclic amines were alkylated with primary and heteroaromatic alcohols. The Ru-NHC Complexes also catalyzed N,C3-dialkylation of cyclic amines.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 N-Heterocyclic Carbenes: Useful Ligands for the Palladium-Catalysed Direct C5 Arylation of Heteroaromatics with Aryl Bromides or Electron-Deficient Aryl Chlorides(Wiley-V C H Verlag Gmbh, 2010) Ozdemir, Ismail; Gok, Yetkin; Ozeroglu, Oezlem; Kaloglu, Murat; Doucet, Henri; Bruneau, ChristianNew Pd-N-heterocyclic carbene complexes have been prepared and employed for palladium-catalysed direct arylation of heteroaromatic derivatives by using aryl halides. These catalyst precursors promote the coupling of challenging aryl halides such as deactivated or congested aryl bromides and also activated aryl chlorides. This procedure employs only 1 mol-% of an air-stable palladium complex. This is a practical advantage over the procedures that employ palladium attached to air-sensitive phosphane ligands, which are often used to promote the coupling of such aryl halides.Öğe New 1,2,4,5-tetrakis-(N-imidazoliniummethyl)benzene and 1,2,4,5-tetrakis(N-benzimidazoliummethyl)benzene salts as N-heterocyclic tetracarbene precursors: synthesis and involvement in ruthenium-catalyzed allylation reactions(Pergamon-Elsevier Science Ltd, 2010) Gurbuz, Nevin; Demir, Serpil; Ozdemir, Ismail; Cetinkaya, Bekir; Bruneau, ChristianNew tetraimidazolinium and tetrabenzimidazolium salts have been prepared Upon reaction with (BuOK)-Bu-t. they generate carbene ligands, which were associated in situ to [RuCp'(MeCN)(3)]PF6 to produce new ruthenium catalysts that are active for the Substitution of allylic substrates by amines, phenols, and carbonucleophiles The influence of the N-heterocyclic core as well as that of the N-substitutents at the periphery of the salts, on reactivity and regioselectivity have been exammed (C) 2009 Elsevier Ltd All rights reservedÖğe PEPPSI-Type Palladium-NHC Complexes: Synthesis, Characterization, and Catalytic Activity in the Direct C5-Arylation of 2-Substituted Thiophene Derivatives with Aryl Halides(Wiley-V C H Verlag Gmbh, 2017) Kaloglu, Murat; Ozdemir, Ismail; Dorcet, Vincent; Bruneau, Christian; Doucet, HenriSix benzimidazolium salts, having two nitrogen atoms substituted by various alkyl groups, have been synthesized in high yields. The benzimidazolium salts readily converted into the corresponding PEPPSI-type palladium-NHC complexes (PEPPSI = pyridine-enhanced precatalyst preparation, stabilization, and initiation). The structures of all compounds have been characterized by H-1 NMR, C-13 NMR, and IR spectroscopy, as well as elemental analysis techniques, which support the proposed structures. The molecular structure of one complex has been determined by single-crystal X-ray diffraction. The catalytic activity of the PEPPSI-type palladium-NHC complexes has been evaluated with respect to the direct C5-arylation of 2-substituted thiophene derivatives with various aryl halides. This arylation occurs efficiently and selectively at the C5-position of 2-substituted thiophene derivatives.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 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 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.Öğe Synthesis, Characterization and Catalytic Activity of New N-Heterocyclic Bis(carbene)ruthenium Complexes(Wiley-V C H Verlag Gmbh, 2009) Ozdemir, Ismail; Demir, Serpil; Gurbuz, Nevin; Cetinkaya, Bekir; Toupet, Loic; Bruneau, Christian; Dixneuf, Pierre H.The reaction of RuCl2(PPh3)(3) with tBuOK-deprotonated ortho-xylyl-bis(N-imidazolinium) salts 1a-d yields RuCl2(PPh3)[bis(imidazolidin-2-ylidene)] complexes (2a-d). Under similar conditions, [RuCl2(p-cymene)](2) leads to the ruthenium complex 3 containing a tridentate eta(6)-arene-dicarbene ligand. All synthesized compounds were characterized by elemental analysis and NMR spectroscopy, and the molecular structures of 2a, 2b and 3 were determined by X-ray crystallography. The catalytic activity of RuCl2(PPh3)[bis(imidazolidin-2-ylidene)] complexes 2a-b was evaluated in the direct arylation of 2-phenylpyridine with chlorobenzene derivatives. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
