In this study, the use of the potentiometric method for the determination of the protonation constant of vinyl imidazole (VIM) and the stability constant of the Cu2+ ion complex of VIM used in the immobilized metal ion affinity chromatography (IMAC) was investigated. For this purpose, poly(ethylene glycol dimethacrylate-n-vinyl imidazole) [poly(EGDMA-VIM)] microspheres (average diameter 150-200 mu m) were prepared. The microspheres were characterized by elemental analysis, N-2 adsorption/desorption isotherms, elemental analysis, energy dispersive spectroscopy (EDS). Protonation constants of vinyl imidazole and the metal-ligand stability constant of vinyl imidazole with Cu2+ ions have been determined potentiometrically in 0.1M NaCl aqueous solution at 298, 318, and 338 K, respectively. The corresponding thermodynamic parameters of protonation and complexation processes (Delta G, Delta H, and Delta S) were derived and discussed. The formation kinetics of Cu2+-vinyl imidazole complex were also investigated, and the process obeyed the pseudo-second-order kinetic model. (C) 2013 Wiley Periodicals, Inc.

In this study, the stability constants of a mixed ligand complex of the yttrium ion by using ethylenediaminetetraacetic acid (EDTA, H(2)A) as a primary ligand and 2,3-dihydroxy benzoic acid (2,3-DHBA, H3B) as a secondary ligand has been investigated. The stability constants of the binary and mixed ligand complexes have been determined by using a potentiometric method and the BEST computer program at 25 degrees C in a 0.1 M NaCl ionic medium. In addition, the identified complex by potentiometry was isolated as solids and the structural characteristics have been examined using IR, NMR, elemental analysis, AAS, ICP-OES, differential thermal analysis, thermogravimetric analysis and the conductivity method.

1-(2-ethyl-1,2,3,4-tetrahydro-quinazolin-2-yl)-ethanone oxime (ETQX, HL) and the Cu(II) complex of its open-chain tautomer were synthesised and characterised by elemental analysis, magnetic susceptibility, molar conductance, thermal analyses, and spectral (IR, NMR, AAS, LC-MS, and UV-Vis) studies. The accumulated data exhibited that the ligand underwent a ring-opening reaction upon formation of a mononuclear Cu(II) complex in which the chain tautomer acted as an N,N,N-donor. The Cu(II) complex was formed in a 1 : 1 (M : HL′) ratio, as indicated by analytical results and the general formula was elucidated to be [Cu(HL′)Cl]Cl. The protonation constants of ETQX and the stability constants of the complex species formed with the Cu(II) of ETQX were studied by the potentiometric method at 25°C in 0.1 M KCl ionic medium. A complexation model for the Cu(II)-ETQX system was established with the software program “BEST” based on the potentiometric data. The concentration distribution curves of ETQX and Cu(II)-ETQX complex species in solution were evaluated by the SPE software program. The stoichiometry of the Cu(II) complex in solution was observed to be similar to that of the solid state Cu(II) complex.

In this study, new heterocyclic ligands, 2-(3-chloro-phenyl)-1,2,3,4-tetrahydro-quinazoline-2-carbaldehyde oxime,(HL1) and 2-(3-bromo-phenyl)-1,2,3,4-tetrahydro-quinazoline-2-carbaldehy- de oxime,(HL2), and Co(III) complexes of their open-chain tautomer,(HL1′ and HL2′), containing oxime, imine, and amine donor groups resulting from the reactions with Co(II) ion have been synthesized and characterized by spectral methods, elemental analysis, magnetic susceptibility, and thermal analysis (TG, DTG, and DTA) techniques. The obtained results show that the ligands undergo a ring-opening reaction upon complexation with Co(III) ion. The analyses confirmed the following molecular formulae: [Co(L1′)2]Cl.H2O and [Co(L2′)2]Cl.H2O.

A new ligand, 2−(p−tolyl)−1,2,3,4−tetrahydroquinazoline−2 −carbaldehyde oxime, was synthesized from a condensation reaction of oxo−p−tolyl−acetaldehyde oxime with 2−aminobenzyl- amine and then amine−imine−oxime complexes of this compound that formed with Co(III) and Ni(II) ions were obtained. All structures were characterized by spectral methods, elemental analysis, magnetic susceptibility, molar conductivity, and thermal analyses. The results that were obtained show that the cyclic ligand, HL, undergoes a ring−opening reaction upon complexation with metal ions. The Co(III) and Ni(II) complexes have a metal−ligand ratio of 1:2 and the imine ligand coordinates through the amine, imine, and oxime groups nitrogen atoms with metal ions.

Bu çalışmanın amacı imidazol grupları içeren çapraz bağlı bir polimerin metal iyonları ile kompleks oluşturma özelliklerinin araştırılmasıdır. Vinil imidazol (VIM) ligandının protonlanma sabiti ile Zn iyonları ve VIM ligandları arasında oluşan kompleksin kararlılık sabitinin belirlenmesinde potansiyometrik yöntem kullanıldı. Vinil imidazol ligandının Zn iyonlarına olan afinitesinin belirlenmesi için ilk olarak çapları 150–200 μm aralığında değişen poli(etilenglikol dimetakrilat-n-vinil imidazol) [poly(EGDMA–VIM)] mikroküreler sentezlendi. Mikroküreler, elemental analiz, N 2 adsorpsiyon/desorpsiyon izotermleri ve enerji dağılım spektroskopisi (EDS veya EDX) ile karakterize edildi. Vinil imidazol ligandının protonlanma sabiti ile VIM ligandı ile Zn iyonları arasında oluşan kompleksin metal-ligand kararlılık sabiti 0.1 M NaCl ortamında 25 C, 35 C ve 45 C sıcaklıkta potansiyometrik olarak belirlendi. Protonlanma ve kompleks oluşumuna ilişkin termodinamik parametreler (ΔG, ΔH, and ΔS) hesaplandı. Zn-vinil imidazol kompleksinin oluşum kinetiği incelendi ve yalancı-ikinci-mertebe olduğu belirlendi. Anahtar Kelimeler Vinil imidazol, çapraz bağlı polimerler, Zn, küreler A B S T R AC T

A new ligand, 2(ptolyl)1,2,3,4tetrahydroquinazoline2 carbaldehyde oxime, was synthesized from a condensation reaction of oxoptolylacetaldehyde oxime with 2aminobenzyl- amine and then amineimineoxime complexes of this compound that formed with Co(III) and Ni(II) ions were obtained. All structures were characterized by spectral methods, elemental analysis, magnetic susceptibility, molar conductivity, and thermal analyses. The results that were obtained show that the cyclic ligand, HL, undergoes a ringopening reaction upon complexation with metal ions. The Co(III) and Ni(II) complexes have a metalligand ratio of 1:2 and the imine ligand coordinates through the amine, imine, and oxime groups nitrogen atoms with metal ions.

In this study, the composition and stability constants of a mixed ligand complex of Sc(III), Y(III) and La(III) ion by using NTA (H3B) (Nitrilotriacetic acid) and HEDTA (H3B) (N-(2-hydroxyethyl)ethylenedinitrilotriacetic acid) as a primary ligand and 2,3-DHBA (H(3)A) (2,3-dihydroxybenzoic acid) as secondary ligand have been determined by using a potentiometric method and the BEST computer programme at 25 degrees C, in a 0.1 M NaCl ionic medium. The complex stability was found to follow the trend Sc(III) > Y(III) > La(III) based on the ionic radius of the metal ions.

The stability constant of a mixed ligand complex of the Scandium ion by using ethylenediaminetetraacetic acid (EDTA, H 2 A) as a primary ligand, and 2,3-dihydroxybenzoic acid (2,3-DHBA, H 3 B) as a secondary ligand has been investigated. The stability constants of the binary and mixed ligand complexes have been determined by using a potentiometric method and the BEST computer program at 25 oC in a 0.1 M NaCl ionic medium. In addition, the identified complex by potentiometry was isolated as solid and the structural characterization have been examined using IR, NMR, elemental analysis, AAS, ICP-OES, differential thermal analysis, thermogravimetric analysis method.  2013 Trade Science Inc. INDIA

The 2-furan-2-yl-1,2,3,4-tetrahydroquinazoline-2-carbaldehyde oxime (HL) and complex of tridentate ligand containing oxime, imine, and amine donors resulting from reactions with cobalt(II) salt have been synthesized and characterized by spectral methods (FT-IR, NMR, UV-Vis, mass), elemental analysis, magnetic susceptibility, molar conductivity, and thermal analysis (TG, DTA) techniques. The molecular structure of HL was elucidated from single-crystal X-ray diffraction. X-ray crystallographic analysis shows that the molecule crystallizes in the monoclinic system, space group C2/c. In the complex, chloride was not coordinated as confirmed by conductivity measurements. The metal is coordinated to the oxime, imine, and amine nitrogen atoms and decomposes with loss of the organic ligand and halogen to leave metal oxide. The metal to ligand ratio was 1 : 2 by elemental analysis and mass spectrum.

A novel 1,2,3,4-tetrahydroquinazoline oxime was synthesised from a condensation reaction of 2-(naphthalen-2-yl)-2-oxoacetaldehyde oxime with 2-aminobenzylamine. Subsequently, a-imine oxime complexes of this compound that formed with Co(III) and Ni(II) metal ions were obtained. All structures were characterised by spectral methods (FT-IR, nmr, AAS, mass), elemental analysis, thermal analyses, magnetic susceptibility and molar conductivity. The analyses confirmed the following molecular formulae: [Co(L)2]Cl • C2H5OH • 0,5H2O and [Ni(HL)2]Cl2. The Co(III) complex is diamagnetic. Magnetic susceptibility measurements revealed octahedral geometry for the Co(III) and Ni(II) complexes. In the complexes, the chloride ion was found to be noncoordinated to the metal ions as confirmed by conductivity measurements. The NMR spectra of the Co(III) complex confirmed the presence ofethanol in the Co(III) complex. The experimental results of TG-DTA showed that the Co(III) complex contained ethanol and crystal water in the first two stages. The end of the thermal decomposition of the complexes yielded a final product of a metal oxide.

In this study, a novel reaction was observed between isonitrosoacetophenone and 1-phenylethanol amine. Acetophenone was used as a starting material to synthesize isonitrosoacetophenone by reaction of acetophenone with n-butyl nitrite in the presence of sodium ethoxide and to synthesize 1-phenylethanol amine by reduction of isonitrosoacetophenone with LiAlH4 in diethyl ether. When the isonitrosoacetophenone reacted with 1-phenylethanol amine, (3E)-3-aza-5-(hydroxyimino)1,4-diphenylpent-3-en-1-ol monohydrate, a new oximino alcohol ligand and amido alcohol were obtained as associated product interestingly. Four complexes were prepared by treatment of oximino alcohol with metal salts such as Cu-II, Ni-II, Zn-II, and Co-II. Amido alcohol was characterized by single-crystal x-ray diffraction, and all complexes were characterized by using spectroscopic techniques and thermogravimetric analysis (TGA).

In this study, the stability constants of a mixed ligand complex of lanthanum(III) ion by using ethylenediaminetetraacetic acid (EDTA, H(2)A) as a primary ligand and 2,3-dihydroxybenzoic acid (2,3-DHBA, H3B) as a secondary ligand have been investigated. The stability constants of the binary and mixed ligand complexes have been determined by using a potentiometric method and the BEST computer program at 25 degrees C, in a 0.1 M NaCl ionic medium. In addition, the identified ternary complex by potentiometry was isolated as a solid, and the structural characteristics have been examined using IR, NMR, elemental analysis, differential thermal analysis, thermogravimetric analysis, and the conductivity method.

ZnO film coated Co-based (2705 X) amorphous ribbons are prepared by the successive ionic layer adsorption and reaction technique. The influence of coating on giant magneto-impedance (GMI) has been investigated over a frequency range from 0.1 to 3.5 MHz and under a static magnetic field between -8 and +8 kA/m. The highest GMI ratio of 15.63% was obtained in the coated Co-based amorphous ribbons which is 80% higher than the sample without coating. The results indicate that the surface coating process plays an important role in the GMI effect.

In this study, UV-Vis and fluorescence properties of two iminooxime ligands and their complexes, which have been previously synthesized, were investigated. UV-Vis. spectrum of the HL, H2L'. H2O and their complexes were measured in chloroform and pi ->pi*, n ->pi*, CT -> M, d -> d transitions were determined. Fluorescence properties of the complexes of HL and H2L'.H2O were studied at room temperature. Measurement results showed that all the complexes display intraligand (pi ->pi*) fluorescence. The optical behavior of the complexes of HL and H2L'.H2O were investigated using optical reflectance and transmittance measurements. The optical band gaps, which turned out to depend significantly on the metal coordination were calculated by optical absorption method. The analysis of the optical absorption data revealed optical direct transition with band gaps of 3.8-4.1 for all of the complexes.

(2E)-3-Aza-1-(hydroxyimino)-2,4-diphenylpent-2-ene (HL) was synthesized by the reaction of isonitrosoacetophenone with I -phenyl-1 -aminoethane in 1: 1 molar ratio. The ligand was characterized by using IR, H-1 NMR, C-13 NMR, UV-vis spectra, elemental analysis, thermal analysis and mass spectroscopy. Ni(II), Cu(II), Co(III) and Zn(II) complexes of this ligand were synthesized and their structures were identified using AAS, IR. electronic spectra, thermal analysis. mass spectroscopy, elemental analyses, conductance and magnetic moment measurements. In the process of obtaining Co(III) complex, when the cobalt(II) chloride solution was added into the alcoholic solution of the ligand gave orange colored complex by air oxidation and this complex was seen polymeric and diamagnetic in nature.

The optical behaviour of the complexes of (2E)-3-aza-1-(hydroxyimino)-2,4-diphenylpent-2-ene (HL) was investigated by optical reflectance and transmittance measurements. The optical constants (refractive index, n; extinction coefficient, k and dielectric constant, e) of some organic thin films were determined using reflectance and transmittance spectra. The optical absorption studies show that the transition is direct with band gap energy values, which are calculated. Analysis of the basis absorption spectra was also carried out to determine optical band gap (E-g) and Urbach parameter (E-o). The analysis of the optical absorption data revealed optical direct transition with band gaps of 3.7-3.9 eV. A surface observation of these thin films was also carried out by an Atomic Force Microscope.

A Copper oxide (CuO) film has been grown on a surface of Co-based amorphous ribbon using chemical successive ionic layer adsorption and reaction technique, at room temperature and atmosphere pressure. The influence of coating and width of ribbon on giant magneto impedance have been investigated over a frequency range from 0.1 to 3MHz and under a static magnetic field between −8 and +8kA/m. The results showed that Co-based amorphous ribbons, which are coated CuO film, have a significant effect on the magnitude and operation frequency for the giant magneto impedance effect as compared to the samples without coating. The highest giant magneto impedance effect was found to be 14.90 on 5mm width coated ribbon, which is 60% higher than the sample without coating. A surface observation of these samples has been carried out by an atomic force microscope. The AFM images reveal the difference between surfaces of coated and as-cast sample.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.