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Öğe Novel neutral phosphinite bridged dinuclear ruthenium(II) arene complexes and their catalytic use in transfer hydrogenation of aromatic ketones: X-ray structure of a new Schiff base, N3,N3?-di-2-hydroxybenzylidene-[2,2?]bipyridinyl-3,3?-diamine(Elsevier, 2010) Aydemir, Murat; Durap, Feyyaz; Baysal, Akin; Meric, Nermin; Buldag, Ayseguel; Guemguem, Bahattin; Oezkar, SaimA novel Schiff base N3,N3'-di-2-hydroxybenzylidene-[2,2']bipyridinyl-3,3'-diamine, 1 was synthesized from condensation of salicylaldehyde with 3,3'-diamino-2,2'-bipyridine. Reaction of 1 with two equivalents of PPh2Cl in the presence of Et3N proceeds in toluene to give N3,N3'-di-2-(diphenylphosphino)benzylidene-[2,2']bipyridinyl-3,3'-diamine, 2 in quantitative yield. Ruthenium(II) dimers [Ru(eta(6)-arene)(mu-Cl)]Cl](2) readily react with phosphinite ligand [(Ph2PO)(2)-C24H16N4], 2 in toluene at room temperature, to afford the neutral derivatives [C24H16N4{OPPh2-Ru(eta(6)-arene)Cl-2}2] {arene: benzene 3, p-cymene, 4}. All the complexes were fully characterized by analytical and spectroscopic methods. P-31-{H-1} NMR, H-1-C-13 HETCOR or H-1-H-1 COSY correlation experiments were used to confirm the spectral assignments. Molecular structure of the Schiff base, 1 was also determined by X-ray single crystal diffraction study. The catalytic activity of complexes 3 and 4 in the transfer hydrogenation of acetophenone derivatives was tested. Stable ruthenium(II)-phosphinite complexes were found to be efficient catalysts in the transfer hydrogenation of aromatic ketones in excellent conversions up to 99% (up to 530 per hour) in the presence of iso-PrOH/KOH. (C) 2010 Elsevier B.V. All rights reserved.Öğe Synthesis and characterizations of 3,3?-bis(diphenylphosphinoamine)-2,2?-bipyridine and 3,3?-bis(diphenylphosphinite)-2,2?-bipyridine and their chalcogenides(Pergamon-Elsevier Science Ltd, 2007) Baysal, Akin; Aydemir, Murat; Durap, Feyyaz; Guemguem, Bahattin; Oezkar, Saim; Yildirim, Leyla TatarNew bis(phosphinoamine) and bis(phosphinite) derivatives of 2,2'-bipyridine were prepared through a single step reaction of 3,3'-diamino-2,2'-bipyridine or 3,3'-dihydroxy-2,2'-bipyridine with diphenylehlorophosphine, respectively. Their P = E chalcogenides (E = 0, S, Se) were also prepared. All the new compounds were characterized by elemental analysis, IR and NMR spectroscopies. The molecular structure of 3.3'-bis(diphenylthiophosphinite)-2,2'-bipyridine was elucidated by single-crystal X-ray crystallography. (c) 2007 Elsevier Ltd. All rights reserved.Öğe Synthesis and characterizations of N,N,N?,N?-tetrakis (diphenylphosphino)ethylendiamine derivatives: Use of palladium(II) complex as pre-catalyst in Suzuki coupling and Heck reactions(Elsevier Science Sa, 2009) Akba, Osman; Durap, Feyyaz; Aydemir, Murat; Baysal, Akin; Guemguem, Bahattin; Oezkar, SaimOxidation of N,N,N',N'-tetrakis(diphenylphosphino)ethylendiamine (1) with elemental sulfur and selenium gives the corresponding sulfide and selenide, respectively, [(Ph2P(E))(2)NCH2CH2N(P(E)Ph-2)(2)] (E: S 1a, Se 1b). Complexes of 1 [(M2Cl4){(Ph2P)(2)NCH2CH2N(PPh2)(2)}] (M: Ni(II) 1c, Pd(II) 1d, Pt(II) 1e) were prepared by the reaction of 1 with NiCl2 or [MCl2(COD)] (M = Pd, Pt). The new compounds were characterized by NMR, IR spectroscopy and elemental analysis. The catalytic activity of Pd(II) complex 1d was tested in the Suzuki coupling reaction and Heck reaction. The palladium complex 1d catalyses the Heck reaction between styrene and aryl bromides as well as Suzuki coupling reaction between phenylboronic acid and arylbromides affording stilbenes and biphenyls in high yield, respectively. (C) 2008 Elsevier B.V. All rights reserved.Öğe Synthesis and characterizations of N,N-bis(diphenylphosphino)ethylaniline derivatives and X-ray crystal structure of palladium (II), platinum (II) complexes(Pergamon-Elsevier Science Ltd, 2008) Durap, Feyyaz; Biricik, Nermin; Guemguem, Bahattin; Oezkar, Saim; Ang, Wee Han; Fei, Zhaofu; Scopelliti, RosarioN,N-Bis(diphenylphosphino)ethylaniline compounds, [Ph2P](2)N-C6H4-C2H5, with ethyl groups at the ortho- and para-positions have been synthesized. Oxidation of the aminophosphines with hydrogen peroxide, elemental sulfur and selenium gave the corresponding oxides, sulfides and selenides [Ph2P(E)](2)N-C6H4-C2H5 (E = O, S, Se). Complexes [MCl2{(Ph2P)(2)N-C6H4-(C2H5)}] (M = Pd, Pt) and [Cu{(Ph2P)(2)N-C6H4-C2H5)(2)]PF6 were obtained by the reaction of NN-bis(diphenylphosphino)ethylaniline with [MCl2(COD)] (M = Pd, Pt) and (Cu(MeCN)(4)]PF6. The new compounds were characterized by NMR, IR spectroscopy and microanalysis. In addition, representative solid-state structures of the palladium and platinum complexes were determined using single crystal X-ray diffraction analyses. (C) 2007 Elsevier Ltd. All rights reserved.Öğe Synthesis, characterization, crystal and molecular structure of diphenyloxophosphinoethylenediamines(Pergamon-Elsevier Science Ltd, 2006) Guemguem, Bahattin; Akba, Osman; Durap, Feyyaz; Yildirim, Leyla Tatar; Uelkue, Dincer; Oezkar, SaimBis-, tris- and tetrakis(diphenyloxophosphino)ethylenediamine compounds can be synthesized starting with ethylenediamine and chlorodiphenylphosphine. Bis(diphenylphosphino)ethylenediamine and tris(diphenylphosphino)ethylenediamine are formed as intermediates and can be oxidized to the respective phosphine oxides by oxygen dissolved in the reaction solution, while tetrakis(diphenylphosphino)ethylenediamine is less liable to oxidation and its oxidation requires a stronger oxidizing agent such as hydrogen peroxide. All the three phosphine oxides and tetrakis(diphenylphosphino)ethylenediamine can be isolated as analytically pure solid materials and are fully characterized by elemental analysis, MS and NMR spectroscopies. The crystal and molecular structure of tris(diphenylphosphino)ethylenediamine was elucidated by single crystal X-ray diffraction analysis. (C) 2006 Elsevier Ltd. All rights reserved.
