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Öğe 1,3-Bis(2-thienylmethyl)-4,5-dihydroimidazolium trichlorido(?6-p-cymene) ruthenate(II)(Int Union Crystallography, 2009) Arslan, Hakan; VanDerveer, Don; Ozdemir, Ismail; Gurbuz, Nevin; Gok, Yetkin; Cetinkaya, BekirThe asymmetric unit of the title compound, (C13H15N2S2)-[RuCl3(C10H14)], contains a 1,3-(2-thienylmethyl)-4,5-dihydroimidazolium cation and a trichlorido(eta(6)-p-cymene)ruthenate(II) anion. The thiophene rings of the cation are disordered by an 180 degrees rotation about the thiophene-CH2 bonds with occupancies of 0.847 (5)/0.153 (5) and 0.700 (5)/0.300 (5), respectively. The Ru atom exhibits a distorted octahedral coordination with the benzene ring of the p-cymene ligand formally occupying three sites and three Cl atoms occupying the other three sites. The short C-N bond lengths in the imidazoline ring indicate partial electron delocalization within the N-C-N fragment. Cation and anions are connected through five intermolecular C-H center dot center dot center dot Cl hydrogen bonds and one C-H center dot center dot center dot pi hydrogen bond, forming a three-dimensional hydrogen-bonded network.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 1,3-Bis(thiophen-2-ylmethyl)-3,4,5,6-tetrahydropyrimidinium trichlorido(?6-p-cymene)ruthenate(II)(Wiley-Blackwell, 2009) Arslan, Hakan; VanDerveer, Don; Ozdemir, Ismail; Gurbuz, Nevin; Gok, Yetkin; Cetinkaya, BekirThe asymmetric unit of the title compound, (C14H17N2S2)-[Ru(C10H14)Cl-3], contains a 1,3-bis(thiophen-2-ylmethyl)-3,4,5,6-tetrahydropyrimidinium cation and a trichlorido(eta(6)-p-cymene) ruthenate(II) anion. The Ru atom exhibits a distorted octahedral coordination with the benzene ring of the p-cymene ligand formally occupying three sites and three chloride atoms occupying the other three sites. The N-C bond lengths of the N-C-N unit of the pyrimidinium cation are shorter than the average single C-N bond length of 1.48 angstrom, thus showing double-bond character, indicating a partial electron delocalization within the N-C-N fragment. The pyrimidine ring has an envelope conformation. Four intermolecular C-H center dot center dot center dot Cl hydrogen bonds generate a three-dimensional hydrogen-bonded framework.Öğe 1,3-Bis[4-(dimethylamino)benzyl]-4,5,6,7-tetrahydro-1H-1,3-diazepan-2-ium chloride(Wiley-Blackwell, 2009) Arslan, Hakan; VanDerveer, Don; Gok, Yetkin; Ozdemir, Ismail; Cetinkaya, BekirThe title N-heterocyclic carbene derivative, C23H33N4+center dot Cl-, has been synthesized and characterized by elemental analysis, H-1 and C-13 NMR, IR spectroscopy and a single-crystal X-ray diffraction study. Ions of the title compound are linked by three C-H center dot center dot center dot Cl interactions. The seven-membered 1,3-diazepane ring has a form intermediate between twist-chair and twist-boat.Öğe 1-(1H-Benzimidazol-1-ylmethyl)-3-[2-(diisopropylamino)ethyl]-1H-benzimidazolium bromide 0.25-hydrate(Int Union Crystallography, 2009) Arslan, Hakan; VanDerveer, Don; Demir, Serpil; Ozdemir, Ismail; Cetinkaya, BekirThe title N-heterocyclic carbene derivative, C23H30N5+center dot Br-center dot 0.25H(2)O, was synthesized using microwave heating and was characterized by H-1 and C-13 NMR spectroscopy and a single-crystal X-ray diffraction study. The structure of the title compound are stabilized by a network of intra-and intermolecular C-H center dot center dot center dot Br hydrogen-bonding interactions. The crystal structure is further stabilized by pi-pi stacking interactions between benzene and imidazole fragment rings of parallel benzo[d] imidazole rings, with a separation of 3.486 (3) angstrom between the centroids of the benzene and imidazole rings. There is also an intermolecular C-H center dot center dot center dot pi interaction in the crystal structure. The C-N bond lengths for the central benzimidazole ring are shorter than the average single C-N bond, thus showing varying degrees of double-bond character and indicating partial electron delocalization within the C-N-C-N-C fragment. The isopropyl group is disordered over two sites with occupancies of 0.792 (10) and 0.208 (10).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 1-(4-tert-Butylbenzyl)-3-(3,4,5-trimethoxybenzyl)benzimidazolium bromide monohydrate(Wiley-Blackwell Publishing, Inc, 2009) Arslan, Hakan; VanDerveer, Don; Demir, Serpil; Ozdemir, Ismail; Cetinkaya, BekirA novel N-heterocyclic carbene derivative, C(28)H(33)N(2)O(3)(+)center dot-Br(-)center dot H(2)O, was synthesized and characterized by elemental analysis, (1)H and (13)C-NMR and IR spectroscopy and a single-crystal X- ray diffraction study. Ions of the title compound are linked by pi center dot center dot center dot pi stacking interactions (face-face separation 3.441 angstrom) and C-H center dot center dot center dot Br and O-H center dot center dot center dot Br interactions. Intra- and intermolecular C-H center dot center dot center dot O interactions are also present. The C-N bond lengths for the compound [1.329 (3), 1.325 (3), 1.389 (3) and 1.391 (3) angstrom] are all shorter than the average single C-N bond length of 1.48 angstrom, thus showing varying degrees of double-bond character.Öğe Bromido[1-(?6-4-tert-butylbenzyl)-3-(2,4,6-trimethylbenzyl)benzimidazol-2-ylidene]chloridoruthenium(II)(Wiley-Blackwell, 2009) Arslan, Hakan; VanDerveer, Don; Ozdemir, Ismail; Demir, Serpil; Cetinkaya, BekirA new ruthenium complex, [RuBrCl(C28H32N2)], has been synthesized and characterized by elemental analysis, H-1 NMR, C-13 NMR, IR-spectroscopy and a single-crystal X-ray diffraction study. The Ru atom in this complex is best described as having a considerably distorted octahedral coordination environment with the arene occupying three coordination sites. Two further coordination sites are occupied by chloride and bromide ligands, while the sixth site is occupied by the carbene. The carbene portion of the ligand is a benzimidazole ring. This ring is connected to the C6H4C(CH3)(3) arene by a CH2 bridge. This leads to a system with very little apparent strain. The two halogen atoms are disordered between Br and Cl. Two partial Cl atoms share the same sites as two partial Br atoms so that the title compound effectively has one Cl and one Br atom. C-H center dot center dot center dot X (X = Cl, Br) hydrogen bonds help to stabilize the crystal structure.Öğe Butylene linked palladium N-heterocyclic carbene complexes: Synthesis and catalytic properties(Elsevier Science Sa, 2011) Demir, Serpil; Ozdemir, Ismail; Arslan, Hakan; VanDerveer, DonNew bis(NHC)-Pd complexes were synthesized and characterized by elemental analysis, H-1 NMR, C-13 NMR, and IR spectroscopy. The reaction of Pd(OAc)(2) and bis(benzimidazolium) salts in DMSO gave the monomeric palladium complex in which the N-heterocyclic carbene was bound to the metal centre. The crystal and molecular structure of the cis-dibromo{1,1'-di[2,3,4,5,6-pentamethylbenzyl]-3,3'-butylene-dibenzimidazol-2,2'-diylidene}-palladium(II) complex was determined by single-crystal X-ray diffraction. The activity of the Pd(II) complexes in the direct arylation of benzothiazole with arylbromides was investigated. A preliminary catalytic study showed that these bis(NHC)-Pd complexes were highly active in the direct arylation of benzothiazole with arylbromides. (C) 2011 Elsevier B.V. All rights reserved.Öğe 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 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 Synthesis and characterization of an N-heterocyclic carbene palladium-based complex(Int Union Crystallography, 2008) Arslan, Hakan; VanDerveer, Don; Demir, Serpil; Ozdemir, Ismail; Cetinkaya, Bekir[Abstract Not Available]Öğe Synthesis and characterization of bidentate NHC-Pd complexes and their role in amination reactions(Pergamon-Elsevier Science Ltd, 2011) Demir, Serpil; Ozdemir, Ismail; Cetinkaya, Bekir; Arslan, Hakan; VanDerveer, DonThe new well-defined and air-stable ortho-xylyl-linked N-heterocyclic carbene (NHC) Pd complexes (2a-d) have been synthesized and characterized by elemental analysis, H-1 NMR, C-13 NMR, IR spectroscopy, and single crystal X-ray diffraction studies. The palladium atom in the complex 2a lies on a crystallographic mirror plane and can be described as having a square-planar coordination environment with the carbene atoms of the benzimidazole rings of the ligand occupying two coordination sites in cis positions. Two further coordination sites are occupied by chloride ligands. The benzimidazole rings are connected to each other by an ortho-xylyl bridge. The catalytic activity of these palladium complexes has been tested in the coupling reactions of various N-containing substrates with bromobenzene. A preliminary catalytic study shows that the bis(NHC)-Pd complexes are highly active in the Buchwald-Hartwig amination reaction. (C) 2010 Elsevier Ltd. All rights reserved.Öğe Synthesis, characterization and catalytic properties of an N-heterocyclic carbene palladium-based complex(Elsevier, 2008) Ozdemir, Ismail; Arslan, Hakan; Demir, Serpil; VanDerveer, Don; Cetinkaya, BekirA palladium(II) complex, bis[1,3-bis-(2,4,6-trimethylbenzyl)benzimidazol-2 -ylidene]palladium(II) chloride, Pd(NHC), bearing N-heterocyclic carbenes has been synthesized and characterized by elemental analysis, IR spectroscopy and H-1 and C-13 NMR spectroscopy. Crystal structure details of Pd(NHC) are also presented. The palladium centre in the complex lies on a crystallographic inversion centre and occupies a square-planar environment. with both chloride and N-heterocyclic carbene ligands adopting a trans arrangement with Cl-Pd-Cl and C-Pd-C angles are precisely 180 degrees. The palladium-carbene complex was tested as a catalyst in the Suzuki-Miyaura cross-coupling reaction. (c) 2008 Elsevier B.V. All rights reserved.Öğe Synthesis, characterization and catalytic properties of cis-dibromo{1,1?-di[3,4,5-trimethoxybenzyl]-3,3?-butylenedibenzimidazol-2,2?-diylidene}palladium (II)(Elsevier Science Bv, 2011) Ozdemir, Ismail; Arslan, Hakan; Demir, Serpil; VanDerveer, Don; Cetinkaya, BekirAn N-heterocyclic carbene palladium-based complex, cis-dibromo{1,1'-di[3,4,5-trimethoxybenzyl]1-3,3'-butylenedibenzimidazol-2,2'-diylidene}palladium(II), has been synthesized and characterized by elemental analysis, IR spectroscopy and H-1- and C-13-NMR spectroscopy. The crystal and molecular structure of the title compound was determined by single-crystal X-ray diffraction. The title compound consists of a 1,1'-di[3,4,5-trimethoxybenzyl]-3,3'-butylenedibenzimidazole and two bromo ligands coordinated to a palladium atom in a distorted square-planar cis-system. Two benzoimidazole rings are connected to each other by a C4H8 bridge. The substituted benzimidazole ligand forms a bidentate chelate with palladium, bonding via the carbene carbon atoms. There are two independent molecules A and B in the asymmetric unit. The Pd-Br bonds are 2.4675(14) and 2.4601(13) angstrom, and the Pd-C-carbene bonds are 1.985(9) and 1.986(9) angstrom for molecule A. Each A and B molecule is stabilized with intra- and inter-molecular hydrogen bonds and C-H center dot center dot center dot n interactions. The palladium-carbene complex was tested as a catalyst in the direct arylation of benzothiazole with arylbromides. The most suitable reaction conditions for the direct arylation of benzothiazole with arylbromides are NMP, K3PO4, Pd-NHC and 130 degrees C. (C) 2011 Elsevier B.V. All rights reserved.
