Hamdi Temel

THE SYNTHESIS AND SPECTRAL CHARACTERIZATION OF NEW Cu(II), Ni(II), Co(III), AND Zn(II) COMPLEXES WITH SCHIFF BASE

ABSTRACT Cu(II), Ni(II), Co(III) and Zn(II) complexes with Schiff base have been prepared. Ligand is derived from condensation of 1,2-bis(p>-aminophenoxy)ethane and 2- hydroxynaphthalin-1-carbaldehyde. The complexes have been characterized by elemental analyses, ΛM, IR, UV-VIS, 1H NMR, 13C NMR and magnetic measurements. The ligand is coordinated to the central metal as a tetradentade ONNO ligand. The four bonding sites are the azomethine nitrogen and aldehydic -OH groups.

NOVEL COMPLEXES OF MANGANESE(III), COBALT(II), COPPER(II), AND ZINC(II) WITH SCHIFF BASE DERIVED FROM 1,2-BIS(p-AMINO-PHENOXY)ETHANE AND SALICYLALDEHYDE

Several new complexes of the Schiff base obtained by the condensation of 1,2-bis(p-aminophenoxy)ethane with salicylaldehyde were synthesized. The complexes have been characterized by elemental analyses, magnetic measurements, 1H NMR, UV-VIS and IR spectra. The ligand is coordinated to the central metal as a tetradentade ONNO ligand. The four bonding sites are the azomethine nitrogen and the o-OH groups.

Preconcentration and determination of copper and cadmium ions with 1,6-bis(2-carboxy aldehyde phenoxy)butane functionalized Amberlite XAD-16 by flame atomic absorption spectrometry

A new chelating resin, covalently linked 1,6-bis(2-carboxy aldehyde phenoxy)butane with the Amberlite XAD-16 was synthesized and used for preconcentration of Cu(II) and Cd(II) prior to their determination by flame atomic absorption spectrometry (FAAS). It was characterized by elemental analyses and Fourier Transform Infrared Spectroscopy (FT-IR). Cu(II) and Cd(II) ions were quantitatively preconcentrated on minicolumn loaded with synthesised resin at pH 4.00 and 6.00, respectively. They were eluated with 5 mL of 0.5 mol L(-1) HCl. Recoveries of Cu(II) and Cd(II) were found to be 100±2.15, 100±1.40 (N=5), the limits of detection of Cu(II) and Cd(II) in the determination by FAAS (3s, N=20) were found to be 0.33 and 1.19 μg L(-1), respectively. The effect of foreign ions on the recovery has been investigated. The proposed method has been applied for the determination of Cu(II) and Cd(II) ions to the real samples collected from Tigris river water in Diyarbakir and Elaziğ cities in Turkey. Standard addition method and analysis of the certified reference material (NCS-DC 73350) was employed to check the accuracy of the method.

New copper(II), manganese(III), nickel(II) and zinc(II) complexes with a chiral quadridentate Schiff base

A chiral Schiff base ligand (H2L) was obtained by condensing 2-hydroxynaphthalene-1-carbaldehyde with substituted (1R,2R)-(−)-diaminocyclohexane. Chiral Schiff base complexes [CuL], [NiL], [ZnL] and [MnLOH] have been synthesized and characterized by elemental analyses, ΛM, i.r., u.v.–vis. and 1H-n.m.r. and magnetic measurements.

SYNTHESIS, SPECTRAL AND BIOLOGICAL STUDIES OF Mn(II), Ni(II), Cu(II), AND Zn(II) COMPLEXES WITH A TETRADENTATE SCHIFF BASE LIGAND. COMPLEXATION STUDIES AND THE DETERMINATION OF STABILITY CONSTANTS (Ke)

The complexes Mn(II), Ni(II), Cu(II) and Zn(II) ions with a N2O2 Schiff base derived from 1,4-diaminobutane and salicylaldehyde, N,N′-bis(salicylidene)-1,4-diaminobutane (LH2), have been prepared and characterized by elemental analyses, molar conductivities, spectral (IR, NMR, visible, UV) and magnetic moment measurements. Stability constants were measured by means of a conductometric method. Furthermore, the stability constants for complexation between ZnCl2, Cu(NO3)2 and AgNO3 salts and the ligand in 80% dioxane-water and pure methanol were determined by conductance measurements. The magnitudes of these ion association constants are related to the nature of the solvation of the cation and the complexed cation. The mobilities of the complexes are also dependent, in part, upon solvation effects. The complexes Mn(II), Ni(II), Cu(II) and Zn(II) ions with the Schiff base have been evaluated for their antibacterial activity against rec − and rec + stains of Bacillus subtilis.

SYNTHESIS AND CHARACTERIZATION OF A NEW BIDENTATE SCHIFF BASE AND ITS TRANSITION METAL COMPLEXES

ABSTRACT The new bidentate Schiff base ligand L was synthesized by treating cinnamaldehyde with 1,2-bis(p-aminophenoxy)-ethane. The complexes of Cu(II), Ni(II), Zn(II) and Mn(II) with the Schiff base have been characterized by magnetic susceptibility, conductance measurements, elemental analyses, IR, UV-Vis, 1H and 13C NMR studies. The analytical, conductance, spectral and magnetic data support the mononuclear formulations of these complexes with M:L=1:2. In addition there are two hydroxo ligands present.

Preparation, characterisation and redox properties of four new tetradentate salicylaldimines with their Cu(II) complexes

Some new tetradentate salicylaldimine ligands of Schiff bases were synthesised by treating 3,5-di-tert-butyl-2-hydroxybenzaldehyde with 1,2-bis-(o-aminophenoxy)ethane, 1,4-bis-(o-aminophenoxy)butane, 1,4-bis-(m-aminophenoxy)buthane and 1,4-bis-(p-aminophenoxy)butane. The compounds were characterised by IR, UV-vis, 1H NMR, 13C NMR, magnetic susceptibility measurements, elemental analysis, molar conductance (ΛM), thermogravimetric analysis (TGA) and cyclic voltammetry. The metal to ligand ratios of the Cu(II) complexes were found to be 1:1. The coordination of the novel tetradentate salicylaldimines appears to occur through the two azomethine nitrogens and two o-OH groups. Cyclic voltammetric studies showed that all of the Cu(II) complexes undergo quasi reversible one-electron transfer redox processes attributed the Cu(II)/Cu(I) couples in dimethylsufoxide. The electron donor affinity of copper(II) complexes increases in order Cu(L4)>Cu(L3)>Cu(L2)>Cu(L1).

THE SYNTHESIS, CHARACTERIZATION AND CONDUCTANCE STUDIES OF NEW Cu(II), Ni(II) AND Zn(II) COMPLEXES WITH THE SCHIFF BASE DERIVED FROM 1,2-BIS-(o-AMINOPHENOXY)ETHANE AND SALICYLALDEHYDE

Cu(II), Ni(II) and Zn(II) complexes with the Schiff base derived from 1,2-bis-(o-aminophenoxy)ethane with salicylaldehyde have been prepared. The complexes have been characterized by elemental analysis, magnetic measurements, 1H NMR, 13C NMR, UV, visible and IR spectra as well as conductance measurements. The ligand is coordinated to the central metal as a tetradentate ONNO ligand. The four bonding sites are the central azomethine nitrogen and aldehydic OH groups. The ligand was used for complexation studies. Stability constants were measured by a conductometric method. Furthermore, the stability constants for complexation between ZnCl2 and Cu(NO3)2 salts and N,N′-bis(salicylidene)-1,2-bis-(o-aminophenoxy)ethane (H2L) in 80% dioxane/water and pure methanol were determined from conductance measurements. The magnitudes of these ion association constants are related to the nature of the solvation of the cation and the complexed cation. The mobilities of the complexes are also dependent, in part, upon solvation effects.

Synthesis and Characterization of a Novel Oxovanadium(IV) Complex and Conductometric Studies with N,N′‐bis(Salicylidene)‐1,2‐bis‐(p‐aminophenoxy)ethane

Abstract A new oxovanadium complex of the Schiff base obtained by the condensation of 1,2‐bis(p‐aminophenoxy)ethane with salicylaldehyde was synthesized. The complex has been characterized by elemental analyses, magnetic measurements, UV‐VIS and IR spectra. Stability constants and thermodynamic values for complexation between Cu(NO3)2, Zn(NO3)2 · 6H2O, and VOSO4 · 5H2O salts and the ligand synthesized by the method described in the literature in 80% dioxane–water and pure methanol were determined by conductance measurements. The stability constants (log K e) in 80% dioxane/water decrease in the order Cu(II) > (Zn(II). However, just the opposite behavior has been obtained for these metal complexes with the ligand in methanol (Zn(II) > (Cu(II)). The magnitudes of these ion association constants are related to the nature of solvation of the cation and of the complexed cation. The mobility of the complexes is also dependent, in part, upon solvation effects. Since the mobility of the VO(IV)L complex has been found to be higher than that of VO(IV) ion, assuming that the complex–solvent interaction in the VO(IV)‐L systems is comparatively weak. A major consequence of the complexation is the increase in the molar conductivity of the complex and a corresponding large decrease in κ values. For this reason, it was not obtained any stability constant values for VO(IV)‐L systems in two type of solvents.

Synthesis, spectral characterization and electrochemical studies of copper(II) and cobalt(II) complexes with novel tetradentate salicylaldimines

Several new complexes of Schiff bases obtained by the condensation of 1,2-bis(p-aminophenoxy)ethane and 1,2-bis(m-aminophenoxy)ethane with 3,5-di-tert-butyl-2-hydroxybenzaldehyde have been synthesized, and characterized by elemental analyses, FT-IR, UV–VIS, 1H NMR spectroscopy, magnetic susceptibility measurements and cyclic voltammetry. The metal to ligand ratios of the Co(II) and Cu(II) complexes were found to be 1 : 1. The coordination of the Schiff base appears to occur through the two azomethine nitrogens and two o-OH groups. Electrochemical data suggest the existence of copper(II)/copper(I) and cobalt(II)/cobalt(I) redox couples in DMSO along with an irreversible oxidation peak assigned to the oxidation of ligands for all of the complexes.