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Publication Metadata only A vic-dioxime ligand bearing fluorescent coumarin moieties and its complexes; preparation, spectroscopy, and electrochemistry(TAYLOR & FRANCIS LTD, 2008) ÖZKAYA, ALİ RIZA; Esenpinar, A. Asli; Kandaz, Mehmet; Ozkaya, Ali Riza; Bulut, Mustafa; Guney, OrhanThe synthesis of a new vic-dioxime ligand, N,N'(2)-dihydroxy-O-1,O-2-bis(4-methyl-2-oxo-2H-chromen-7-yl)oxalimidamid (LH2) (1), bearing functional coumarins and its soluble mono- {Ni(II), Cu(II), Co(II)} and dinuclear {UO2(II)} complexes are presented. The fluorescence properties due to the 7-hydroxy-4-methylcoumarin fluorophore, which is conjugated with vic-dioxime that functions as the MN4 core of 1 and its complexes, are also reported. The formation of coordination complexes resulted in the blue shift in excitation spectrum and fluorescence quenching of 1. Both mononuclear {(LH)(2)M, M=Ni(II), Cu(II), and Co(II)} and homodinuclear {(LH)(2)(UO2)(2)(OH)(2))} complexes have been obtained with metal : ligand ratios of 1 : 2 and 2 : 2, respectively. The characterizations of the new compounds were made by elemental analysis, H-1-NMR, FT-IR, UV-Vis, and LCMS data. Redox behavior of 1, involving oxime and coumarin moieties, and its complexes with Ni(II), Cu(II), Co(II) and UO2(II) were investigated by cyclic voltammetry. The comparison of the electrochemical behavior of 1 with its complexes enabled us to identify metal-, oxime- and coumarin-based signals.Publication Metadata only Coumarin-derivatized fluorescent vic-dioxime-type ligand and its complexes; the preparation, spectroscopy, and electrochemistry(SPRINGER, 2007) ÖZKAYA, ALİ RIZA; Camur, Meryem; Bulut, Mustafa; Oezkaya, Ali R.; Kandaz, Mehmet; Yayli, NurettinA new vic-dioxime bearing coumarin functionality, N-'1, N-'2-Dihydroxy-N1, N2-bis(4-methyl-2-oxo-2H-chromen-7yl) oxalimidamid (LH2), N,N-bis-[4-methylcoumarinyl]-diamino glyoxime (LH2), and its mono- and dinuclear complexes {copper(II), cobalt(II), nickel(II) and uranyl(II)} have been reported. The. uorescence excitation and emission spectra of LH2 and its complexes with metal ions were examined. It was observed that. uorescence and excitation emission intensity of LH2 was quenched depending on complex formation with metal ions. The characterizations of all newly synthesized compounds were made by elemental analysis, H-1-n.m.r,i.r.,u.v.-vis., and l.c-m.s. m.s. data. Electrochemical behaviour of the ligand involving oxime and coumarine moieties, and its complexes with Ni-II, Cu-II, Co-II and UO2II were investigated by cyclic voltammetry. The comparison of the electrochemical behaviour of the ligand with its complexes enabled us to identify metal-, oxime- and coumarine-based signals.Publication Open Access Fluorescent vic-dioxime-type ligand and its mono- and dinuclear complexes: The preparation, spectroscopy, and electrochemistry of its various complexes(ELSEVIER SCI LTD, 2008-01) ÖZKAYA, ALİ RIZA; Oezer, Metin; Kandaz, Mehmet; Oezkaya, Ali Riza; Bulut, Mustafa; Gueney, OrhanA new coumarin functionalized vic-dioxime, S,S-bis-[4-methylcoumarinyl]-dithioglyoxime (LH2), and its soluble mono- and dinuclear complexes [nickel(II), copper(II), cobalt(II), and uranyl(II)] have been reported. The fluorescent properties of the ligand and its complexes are due to the 7-mercapto-4-methylcoumarin fluorophore, which is conjugated with vic-dioxime that functions as the MN4 core. Fluorescence spectra of the probe showed a clear shift in excitation wavelength maxima upon metal binding indicating its potential use as ratio-metric metal indicator. The fluorescence of complexes was found to be highly sensitive to both polarity and protic character of the solvent used. Both mononuclear (LH)(2)M (M = Ni, Cu and Co) and homodinuclear (LH)(2)(UO2)(2)(OH)(2)) complexes have been obtained with the metal ligand ratios of 1:2 and 2:2, respectively. The characterizations of all newly synthesized compounds were made by elemental analysis, H-1 NMR, FT-IR, UV-vis, and mass (LSI-MS) data. The electrochemical investigation of the Ni(II), Cu(II), Co(II) and UO2(II) Complexes in comparison with the ligand involving oxime and coumarin moieties enabled us to identify metal-, oxime- and coumarin-based signals. (C) 2006 Elsevier Ltd. All rights reserved.Publication Metadata only Functional alcohol-soluble double-decker phthalocyanines: synthesis, characterization, electrochemistry and peripheral metal ion binding(WORLD SCI PUBL CO INC, 2006) Yarasir, Meryem N.; Kandaz, Mehmet; Koca, Atif; Salih, BekirIn this study we report the preparation, physical characterization and electrochemistry of peripherally functionalized substituted ionophore double-decker lanthanide phthalocyanines, lanthanide bis-[(4,4',4,4')-tetrakis-(6-hydroxyhexylthio)phthalocyaninates], {M[Pc(S-C6H13OH)(4)](2)} (M = Pr-III, Yb-III, and Lu-III). All benzenes on the double-decker phthalocyanines are functionalized with hydroxyhexylsulfanyl moieties for potential use as metal ion binding and surface anchors. The double-decker phthalocyanines synthesized from the anhydrous metal salts {Ln(acac)(3)} and the corresponding 4-(6-hydroxyhexylthio)-1,2-dicyanobenzene exhibit ion-specific optical changes in the presence of Ag+ and Pd2+. Thio donors of the complexes coordinate to Ag+ and Pd2+ to give 4:1 metal-phthalocyanine complexes. Newly synthesized lanthanide double-decker phthalocyanines are soluble in methanol (MeOH), ethanol (EtOH), tetrahydrofuran (THF), dimethylformamide (DMF), dimethylsulfoxide (DMSO), chloronapthalene, quinoline and less soluble in i-PrOH and acetonitrile. Electrochemical studies reveal that all lanthanide-base complexes undergo ligand-based redox processes. The smaller HOMO-LUMO gaps of the complexes indicate the existence of strong pi-orbital interactions between the rings of the sandwich. The newly synthesized compounds have been characterized by elemental analysis, FTIR, H-1 and C-13 NMR, MS (ESI and MALDI-TOF), UV-vis and EPR spectral data. Copyright (c) 2006 Society of Porphyrins & Phthalocyanines.Publication Metadata only Vic-dioxime complexes bearing carboxyester and picolyl amide functionality: synthesis, characterization, spectroscopy, electrochemistry, and electrical properties(SPRINGER WIEN, 2013) KOCA, ATIF; Yarasir, Meryem N.; Kandaz, Mehmet; Akyildiz, Ali; Karadeniz, Kemal; Dumludag, Fatih; Koca, AtifWe have synthesized a vic-dioxime, [(1Z,2Z)-bis(2-oxo-2-(pyridin-2-ylmethylamino)ethyl)-N'1,N'2-dihydroxyethanebis(imidothioate)] (LH4) via dimethyl 2,2'-(1,2-bis(hydroxyimino)ethane-1,2-diyl)bis(sulfanediyl)diacetate (LH2) and 2-(aminomethyl)pyridine by using the condensation technique. The formation of mononuclear (Ni(II), Cu(II)) and homodinuclear (LH)(2)(UO2)(2)(OH)(2)) complexes of LH2 and mononuclear Cu(II) and homotrinuclear ((LH)(2)M-3, M=Cu(II) and Ni(II)) complexes of LH4 were also obtained simultaneously with metal:ligand ratios of 1:2, 2:2 and 1:2, 3:2, respectively. The structure of the dioxime and its complexes are proposed in accordance with the elemental analysis, NMR, UV-Vis, FT-IR, and MS-FAB spectral data. The voltammetric analyses of the complexes showed metal- and ligand-based signals. The redox chemistry of the complexes exhibited various oxidation states of the central metals of the complexes. DC and AC conductivity measurements were performed at room temperature under vacuum in the dark. I-V characteristics of the complexes showed ohmic behavior. AC conductivity of the homotrinuclear copper and nickel increased and impedance of the same complexes decreased with increasing frequency.