Yazar "Gurbuz, Nevin" seçeneğine göre listele

Listeleniyor 1 - 12 / 12
  • Küçük Resim Yok
    Öğe
    1,3-Bis(thiophen-2-ylmethyl)-3,4,5,6-tetrahydropyrimidinium trichlorido(eta(6)-p-cymene)ruthenate(II)
    (Wiley-Blackwell, 2009) Arslan, Hakan; VanDerveer, Don; Ozdemir, Ismail; Gurbuz, Nevin; Gok, Yetkin; Cetinkaya, Bekir
    The 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.
  • Küçük Resim Yok
    Öğe
    Cross coupling reactions catalyzed by (NHC)Pd(II) complexes
    (Scientific Technical Research Council Turkey-Tubitak, 2015) Gurbuz, Nevin; Karaca, Emine Ozge; Ozdemir, Ismail; Cetinkaya, Bekir
    This review is focused on new developments reported during the last 3 years concerning the catalytic performances of in situ formed or preformed NHC Pd(II) complexes (NHC: N-heterocyclic carbene) for cross-coupling reactions such as Heck Mizoraki (often shortened to the Heck reaction), Kumada, Negishi, Suzuki Miyaura (often shortened to the Suzuki reaction), Sonogashira and Hiyama couplings, and the Buchwald-Hartwig aminations, which are extremely powerful in the formation of C-C and C-heteroatom bonds. Due to the great number of publications and limited space here, we made a special attempt to compile the relevant data in tables, which we hope will serve as a guide for chemists interested in these reactions. The syntheses of the precatalysts and the generally accepted reaction mechanisms are also briefly described.
  • Küçük Resim Yok
    Öğe
    In situ catalytic activities of 1,3-dialkyltetrahydropyrimidinium salts/[RuCl2(p-cymene)](2) system for transfer hydrogenation reactions
    (Scientific Technical Research Council Turkey-Tubitak, 2011) Ozcan, Emine Ozge; Mercan, Deniz; Gurbuz, Nevin; Cetinkaya, Engin; Cetinkaya, Bekir; Ozdemir, Ismail
    Hydrogen-transfer reduction processes are attracting increasing interest from synthetic chemists in view of their operational simplicity. In the present study novel ruthenium carbene complexes were generated in situ and tested for their transfer hydrogenation reactions. The in situ prepared 3 component 1,3-dialkyltetrahydropyrimidinium salts (LHX)/[RuCl2(p-cymene)](2) and KOH catalyzed quantitatively the transfer hydrogenation of ketones under mild reaction conditions in 2-propanol.
  • Küçük Resim Yok
    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, Bekir
    The 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.
  • Küçük Resim Yok
    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, Bekir
    The 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.
  • Küçük Resim Yok
    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, Bekir
    The 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.
  • Küçük Resim Yok
    Öğe
    Palladium N-heterocyclic-carbene-catalyzed ortho-arylation of benzaldehyde derivatives
    (Wiley-Blackwell, 2008) Dogan, Oznur; Gurbuz, Nevin; Ozdemir, Ismail; Cetinkaya, Bekir
    New, sterically demanding 1,3-dialkylbenzimidazolium salts (2a-c) as N-heterocyclic-carbene precursors have been synthesized and characterized. The ortho position of aromatic aldehydes was directly and selectively arylated with aryl chlorides in the presence of a catalytic system prepared in situ from Pd(OAc)(2), 1,3-dialkylbenzimidazolium chlorides (2a-c), and Cs(2)CO(3). (C) 2008 Wiley Periodicals, Inc.
  • Küçük Resim Yok
    Öğe
    Preparation of a series of Ru(II) complexes with N-heterocyclic carbene ligands for the catalytic transfer hydrogenation of aromatic ketones
    (Royal Soc Chemistry, 2012) Gurbuz, Nevin; Ozcan, Emine Ozge; Ozdemir, Ismail; Cetinkaya, Bekir; Sahin, Onur; Buyukgungor, Orhan
    The reaction of [RuCl2(p-cymene](2) with Ag-N-heterocyclic carbene (NHC) complexes yields a series of [(p-cymene) Ru(NHC)] complexes (2a-f). All synthesised compounds were characterized by elemental analysis, NMR spectroscopy and the molecular structure of 2a was determined by X-ray crystallography. All complexes have been tested as catalysts for the transfer hydrogenation of aromatic ketones, showing excellent activity in this reaction.
  • Küçük Resim Yok
    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, Ismail
    The 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.
  • Küçük Resim Yok
    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)
  • Küçük Resim Yok
    Öğe
    Synthesis, characterization and catalytic activity of novel N-heterocyclic carbene-palladium complexes
    (Royal Soc Chemistry, 2009) Dogan, Oznur; Gurbuz, Nevin; Ozdemir, Ismail; Cetinkaya, Bekir; Sahin, Onur; Buyukgungor, Orhan
    The reaction of Pd(OAc)(2) with 1-(benzhydryl)-3-(alkyl) benzimidazolium salts 1a-d yields trans-bis[1-(benzhydryl)-3-(alkyl)benzimidazolin-2-ylidene]dibromopalladium(II) complexes (2a-d) which were characterized by elemental analysis, NMR spectroscopy and the molecular structures of 2b, and 2d were determined by X-ray crystallography. The catalytic activity of PdBr(2)bis(benzimidazolin-2- ylidene) complexes 2a-d was evaluated in the direct arylation reaction of benzothiazole with bromobenzene derivatives.
  • Küçük Resim Yok
    Öğe
    Transfer Hydrogenation of Ketones by Ruthenium Complexes Bearing Benzimidazol-2-ylidene Ligands
    (Wiley-Blackwell, 2010) Gurbuz, Nevin; Yasar, Sedat; Ozcan, Emine Oezge; Ozdemir, Ismail; Cetinkaya, Bekir
    A series of benzimidazolium ligand precursors were metalated with [RuCl(2)(p-cymene)](2) to give ruthenium(II) N-heterocyclic carbene complexes. All compounds were fully characterized by elemental analyses, (1)H NMR, (13)C NMR, and IR spectroscopy. The new benzimidazol-2-ylidene complexes have been found to be effective catalysis for the transfer hydrogenation of ketones by using 2-propanol as the hydrogen source in the presence of KOH.