Search Results

Now showing 1 - 3 of 3
  • Article
    Citation - WoS: 36
    Citation - Scopus: 42
    Synthesis, Spectroscopy and Electrochemical Behaviors of Nickel(ii) Complexes With Tetradentate Shiff Bases Derived From 3,5-bu2t<
    (Pergamon-elsevier Science Ltd, 2005) Kasumov, VT; Özalp-Yaman, S; Tas, E
    Nickel(II) complexes of a series of N,N'-polymethylenebis(3,5-Bu'(2)-salicylaidimine) ligands containing 2,4-di-Bu'(2)-phenol arms, NiLx, were synthesized and their spectroscopic and redox properties were examined. The UV-vis, H-1 NMR spectroscopic and magnetic results indicate that complexes NiL1-NiL4 unlike NiL5 and NiL6 have a square-planar structure in the solid state and in solution. Cyclic voltammograms of NiLx (x= 1-4) complexes displayed two-step oxidation processes. The first oxidation peak potentials of all Ni(II) complexes corresponds to the reversible one-electron oxidation process of the metal center, yielding Ni(III) species. The second oxidation peak of the complexes was assigned as the ligand based oxidation generating a coordinated phenoxyl radical species. (c) 2005 Elsevier B.V. All rights reserved.
  • Article
    Citation - WoS: 3
    Citation - Scopus: 3
    Spectroelectrochemical Investigation of Nuclease Active Pt(II) Complexes Containing Pyrrole Oxime
    (Pergamon-elsevier Science Ltd, 2015) Erdogan, Deniz Altunoz; Kayi, Hakan; Ozalp-Yaman, Seniz
    In this paper, the electrochemical oxidation of three Pt(II) complexes containing pyrrole oxime (HL) having a general formula of [Pt(NH3)Cl(L)] (1), [Pt(L)(2)] (2), and K[PtCl2(L)] (3) has been investigated by in-situ spectroelectrochemistry in dimethylformamide (DMF). An irreversible metal-based oxidation process occurs during the anodic scan for each of the three complexes. The electronic absorption spectral changes indicate that all the three complexes generate similar Pt(IV) compounds and free ligand. Our experimental data is supported by quantum chemistry calculations utilizing density functional theory. In addition, the frontier orbital energy distributions indicate that electron densities are localized on mainly platinum atom. (C) 2015 Elsevier Ltd. All rights reserved.
  • Article
    Citation - WoS: 14
    Citation - Scopus: 12
    Synthesis, Characterization, Redox Behavior and Hydrogenation Catalytic Activity of Bis(n-aryl-3, 5-but< Complexes
    (Pergamon-elsevier Science Ltd, 2005) Kasumov, VT; Tas, E; Köksal, F; Özalp-Yaman, S
    The synthesis, spectroscopic (H-1 NMR, IR, UV-Vis), electron-transfer properties and catalytic reactivity of new palladium(II) complexes, with N-aryl-3,5-Bu-2(t)-salicylaldimines prepared from 3,5-Bu-2(t)-salicylaldehyde and o-,p-substituted anilines (X-C6H4NH2, X = H. F. Cl, Br, CH3, OCH3, t-Bu, 5,6-benzo) are reported. Cyclic voltammetry studies of the complexes exhibit an irreversible anodic peak that corresponds to the phenoxide/phenoxyl oxidation. The chemical oxidation of the complexes with (NH4)(2)Ce(NO3)(6) in CHCl3, besides relatively stable Pd-II-phenoxyl radical complexes (g = 2.0083-2.0114), also generate nitroxide radicals exhibiting strongly anisotropic spectra (g(parallel to) = 2.0061, g(perpendicular to) = 2.0072, A(parallel to) = 37.5, A(perpendicular to) = 5.38 G) typical for immobilized nitroxide radicals. It has been found that the introduction of t-Bu groups on the salicylic ring increases catalytic activity of towards hydrogenation of nitrobenzene in DMF at room temperature. (C) 2004 Elsevier Ltd. All rights reserved.