Gazi Irez

A Co(III) complex with a tridentate amine-imine-oxime ligand from 1,2,3,4-tetrahydroquinazoline: synthesis, crystal structure, spectroscopic and thermal characterization

A cobalt(III) complex [Co(L)2]Cl · PPO · H2O (1) (HL = 1-(2-aminobenzylimino)-1-phenyl-propan-2-one oxime, PPO = 1-phenyl-1,2-propanedione-2-oxime) has been synthesized and characterized by elemental analyses, spectral, thermal, magnetic and molar conductance measurements and single crystal X-ray diffraction. It crystallizes in the monoclinic crystal system, space group P21/c. Complex 1 consists of one uncoordinated water, one 1-phenyl-1,2-propanedione-2-oxime molecule, one bis[1-(2-aminobenzylimino)-1-phenyl-propan-2-one oxime]cobalt(III) cation and one uncoordinated chloride. The coordination geometry around Co is slightly distorted octahedral, completed with six nitrogens of two L− ligands. The oxime moieties have E configurations. In the crystal structure, intramolecular O–H···Cl and N–H···O and intermolecular N–H···O, O–H···Cl and N–H···Cl hydrogen bonds link the molecules into chains parallel to the c axis; hydrogen-bonded PPO molecules fill the spaces between the chains and stabilization of the structure.

Giant Magneto–Impedance Effect in Thin Zinc Oxide Coated on Co-Based (2705 X) Amorphous Ribbons

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.

Syntheses and characterizations of a novel 1,2,3,4-tetrahydroquinazoline and a Co(III) complex

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 Reaction of α-Carbonyl Oxime and Amido Alcohol: Synthesis, Characterization, Crystal Structure, and Thermal Studies of an Amido Alcohol, a New Oximino Alcohol Ligand, and its Metal Complexes

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 CuII, NiII, ZnII, and CoII. Amido alcohol was characterized by single-crystal x-ray diffraction, and all complexes were characterized by using spectroscopic techniques and thermogravimetric analysis (TGA).

Syntheses, Structural Characterization, and Thermal Properties of New 1,2,3,4-Tetrahydroquinazoline Ligands and Their Co(III) Complexes

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 Cyclic Ligand and Complexes of Its Open-Chain Tautomer With Co(III) and Ni(II) Ions: Synthesis, Characterization and Thermal Properties

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.

Synthesis, characterisation, and equilibrium studies of 1-(2-ethyl-1,2,3,4-tetrahydro-quinazolin-2-yl)-ethanone oxime and the copper(II) complex of its open-chain tautomer

Abstract1-(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.