Browsing by Author "Tas, E"
Now showing 1 - 2 of 2
- Results Per Page
- Sort Options
Article Citation Count: 14Synthesis, characterization, redox behavior and hydrogenation catalytic activity of bis(N-aryl-3, 5-But2-salicylaldiminato)palladium(II) complexes(Pergamon-elsevier Science Ltd, 2005) Özalp Yaman, Şeniz; Tas, E; Köksal, F; Özalp-Yaman, S; Chemical EngineeringThe 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.Article Citation Count: 37Synthesis, spectroscopy and electrochemical behaviors of nickel(II) complexes with tetradentate shiff bases derived from 3,5-Bu2t-salicylaldehyde(Pergamon-elsevier Science Ltd, 2005) Özalp Yaman, Şeniz; Özalp-Yaman, S; Tas, E; Chemical EngineeringNickel(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.