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Coordination Chemistry of Nickel(II), Copper(II), Two Novel vic-Dioximes Ligands. Synthesis, Spectroscopy and Redox Properties

Kilic A., Tas E., Gumgum B., Yilmaz I.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 12

1967-1981

EN

Two new vic-dioxime, N-(4-amino-1-benzyl piperidine)-anti-phenylglyoxime (L1H2) and N-(4-amino-1-benzyl piperidine)-anti-glyoxime (L2H2) were prepared by the reaction of anti-phenylchloroglyoxime and anti-monochloroglyoxime with 4-amino- 1-benzyl piperidine in absolute THF at -15°C. Mononuclear nickel(II), copper(II), and cobalt(II) complexes have a metal-ligand ratio of 1:2 in which the ligands coordinate through the two nitrogen atoms as do most vic-dioximes. The ligands and their Co(II), Cu(II), and Ni(II) complexes were characterized by elemental analyses, FT-IR, UV-vis, 1H-NMR and 13C-NMR, magnetic susceptibility measurements, electrical conductivity measurements and cyclic voltammetry. The electrical conductivity of Ni(II), Co(II), and Cu(II) metal complexes were measured using Four-Point Probe analysis. The electrochemical behavior of theNi(II), Co(II), andCu(II) complexeswere investigated by cyclic

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Coordination Chemistry of Nickel(II), Copper(II), and Cobalt(II) with MN4 Core-Containing Two Novel vic-Dioximes Ligands. Synthesis, Spectroscopy and Redox Properties

Kilic A., Tas E., Gumgum B., Yilmaz I.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 12

1967-1981

EN

Two new vic-dioxime, N-(4-amino-1-benzyl piperidine)-anti-phenylglyoxime (L1H2) and N-(4-amino-1-benzyl piperidine)-anti-glyoxime (L2H2) were prepared by the reaction of anti-phenylchloroglyoxime and anti-monochloroglyoxime with 4-amino- 1-benzyl piperidine in absolute THF at –15°C. Mononuclear nickel(II), copper(II), and cobalt(II) complexes have a metal-ligand ratio of 1:2 in which the ligands coordinate through the two nitrogen atoms as do most vic-dioximes. The ligands and their Co(II), Cu(II), and Ni(II) complexes were characterized by elemental analyses, FT-IR, UV-vis, 1H-NMR and 13C-NMR, magnetic susceptibility measurements, electrical conductivity measurements and cyclic voltammetry. The electrical conductivity of Ni(II), Co(II), and Cu(II) metal complexes were measured using Four-Point Probe analysis. The electrochemical behavior of theNi(II), Co(II), andCu(II) complexeswere investigated by cyclic voltammetry in DMSO.

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Synthesis, Characterization and Redox Properties of Novel vic-Dioximes and Their Complexes with Nickel(ii), Copper(II) and Cobalt(II)

Tas E., Aslanoglu M., Kilic A., Ulusoy M ., Guler M.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 11

1739-1747

EN

Two novel vic-dioxime, 1,2-dihydroxyimino-1-p-tolyl-3-aza-6-imidazole heptane (L1H2) and N-(ethyl-4-amino-1-piperidine carboxylate)-p-tolylglyoxime (L2H2) were prepared by the reaction of anti-p-tolylchloroglyoxime with 1-(3-aminopropyl)imidazole and ethyl-4-amino-1-piperidine carboxylate in absolute THF. Mononuclear complexes with a metal-ligand ratio of 1:2 were prepared using Co(II), Cu(II) and Ni(II) salts. The ligands and their Co(II), Cu(II) and Ni(II) com plexes were characterized by elemental analyses, FT-IR, UV-Vis, 1H-NMR and 13C-NMR and magnetic susceptibility measurements. The electrochemical behaviour of the complexes was investi ated by cyclic voltammetry in dimethylsulfoxide. All metal complexes showed metal centered quasi reversible one-electron redox processes. How ever, metal complexes of the L2H2 ligand also ex hibited ligand based irreversible redox waves.

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Magnetic, Electrochemical and Antimicrobial Properties of Some Cu(II) Complexes with TPMC

Vuckovic G., Antonijevic-Nikolic M., Korabik M., Mroziński J., Manojlovic D., Gojgic-Cvijovic G., Matsumoto N.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 4

679-687

EN

Three complexes: [Cu2(C6H5COO)tpmc](ClO4)3.CH3OH, (A), (tpmc = N,N',N'',N'''- tetrakis(2-pyridilmethyl)-1,4,8,11-tetraazacyclotetradecane), [Cu2(Hpht)tpmc](ClO4)3.3H2O (H2pht = phtalic acid) (B) and [Cu4(ipht)(tpmc)2](ClO4)6_NaClO4_2CH3CN (H2ipht = isophtalic acid) (C) previously described were investigated by magnetic measurements, cyclic voltammetry (CV) and were tested towards some strains of microorganisms. It is found that all three complexes were electrochemically stable in the investigated ranges. The least stable was mi-iphtcomplex (C) due to the reaction of central ion, which is seen from weak peaks in its cyclic voltammogram. Complexes were characterized by variable temperature magnetic measurements (4.2-300 K) and the observed data were successfully simulated by the equation based on the spin Hamiltonian operator, H= - 2JSS1 2, giving the ferromagnetic exchange parameters J = 0.92 cm-1 forA, J = 0.55 cm-1 forB and J= 0.65 cm-1for C. For the complex C model of molecular magnet with two magnetically isolated dimeric subunits was used. These results indicate the presence of weak ferromagnetic spin exchange interaction between the CuII magnetic centers within each molecule.

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EPR study of chromium centres in CrAPO-5 molecular sieves

Padylak B., Kornatowski J., Zadrożna G., Fabisiak K., Gutsze A.

Materials Science Poland

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2005

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Vol. 23, No. 4

1035--1046

EN

The X-band EPR spectra of CrAPO-5 molecular sieves exhibiting high or low sorption capacities for nitrogen and benzene, signed HS and LS samples, respectively, were studied at 300 and 77 K. The EPR spectra of the as-synthesized HS and LS samples consist of a broad intense signal (geff = 1.971 ± 0.001, ΔHpp ≅ 500 G) with a positive lobe at geff = 5.15±0.01, assigned to Cr3+ (3d3, 4F3/2) ions with a rhombic distorted octahedral coordination. Calcined samples show an additional narrow EPR signal of axial symmetry with g|| = 1.971 ± 0.001 and g⊥ = 1.959 ± 0.001, also assigned to Cr5+ (3d1, 2D3/2) ions in an octahedral coordination. HS samples heated under vacuum exhibit a decrease in the intensity of the Cr3+ lines as well as several new signals. Two of them are characterized by an axially symmetric g factor and belong to Cr5+ centres in square pyramidal and tetrahedral coordination. The third signal may be assigned to Cr+ (3d5, 6S5/2) ions. The EPR spectra of LS samples heated under vacuum show a strong decrease in the intensity of Cr3+ lines and only the two signals of Cr5+ centres in the same coordination. Their g factors are similar to those in the HS samples. Thermal treatment under oxidative (O2) and reductive (H2) atmospheres reveal the reproducible redox properties of Cr5+ ions and a high stability of Cr3+ ions, especially in the HS samples.

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Synthesis, Characterization and Electrochemical Studies of Nickel(II) and Cobalt(II) Complexes with Novel Bidentate Salicylaldimines

Tas E., Aslanoglu M., Ulusoy M., Guler M.

Polish Journal of Chemistry

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2004

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Vol. 78 / nr 7

903-909

EN

Several mononuclear Ni(II) and Co(II) complexes of bidentate salicylaldimines (LxH), derived from 3,5-di-tert-butyl-2-hydroxybenzaldehyde with biologically active amines [1-(3-aminopropyl)imidazole, 4-(3-aminopropyl)morpholine, 1-(3-aminopropyl)-2-pyrrolidinone], have been synthesized. The complexes have been characterized by FT-IR, UV-vis, MS, 1H-NMR and 13C-NMR, magnetic susceptibility measurements, thermogravimetric analyses (TGA) and electrochemistry. As a result of thermal analyses, Co(L3)2 has highest thermal stability of the complexes, whereas the smallest one has Ni(L2)2. Electrochemical experiments indicated that Ni(II) and Co(II) complexes show quasi reversible reduction to Ni(I) and Co(I), respectively.