Fe(III), Co(II,III), and Ni(II) phenanthrolinate peroxodisulfates

Complexes with the compositions [Fe(Phen)₃]₂(S₂O₈)₃ · 2H₂O, [Co(Phen)₃]₂(S₂O₈)₃ · 8H₂O, Co(Phen)₂S₂O₈ · 3H₂O, and [Ni(Phen)₂(H₂O)₂]S₂O₈ were synthesized and studied by spectroscopic, X-ray powder diffraction, and TG methods.     

Spectrophotometric Study of Mithramycin Complexes with Cu(II), Fe(III) and Tb(III)

Abstract

The coordination of the anticancer drug mithramycin to Tb(III), Fe(III) and Cu(II) was studied in aqueous solution using absorption measurements. The stability constants were calculated from equilibrium competition experiments by means of the SQUAD program. For both first ions, the competitor was oxalic acid and for the latter the competitor was the Cu(II) ions. Cu(II) at pH 7.5, Fe(III) at pH 3.5 and Tb(III) at pH 5.5 formed respectively 1:2, 1:3 and 1:4 metal-to-ligand species.     

Synthesis and characterization of Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) complexes with N-salicydene-o-hydroxymethyleneaniline

The new Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) complexes with tridentate Schiff base, the product of condensation of o-aminobenzyl alcohol with salicylaldehyde have been synthesized and characterized by elemental analysis, IR, electronic, EPR and Mössbauer spectra, thermal analysis, magnetic susceptibility and molecular weight measurements. Dimeric or polymeric structures for the investigated complexes were proposed. The interaction of the cobalt complex with dioxygen is also described.     

Organic acid solutions in the chromatography of inorganic ions VIII. Cation-exchange of Mn(II), Cd(II), Co(II), Ni(II), Zn(II), Cu(II), Fe(III), Sc(III), Y(III), Eu(III), Dy(III), Ho(III), Yb(III), Ti(IV) and Nb(V) in malate media

Summary The cation-exchange behaviour of Mn(II), Cd(II), Co(II), Ni(II), Zn(II), Cu(II), Fe(III), Sc(III), Y(III), Eu(III), Dy(III), Ho(III), Yb(III), Ti(IV) and Nb(V) in malate media at various concentrations and pH, was studied with Dowex 50 WX8 resin (200–400 mesh) in the ammonium form. Separation of Fe(III)/Cu(II), Fe(III)/Cu(II)/Zn(II), Fe(III)/Co(II)/Mn(II), Cu(II)/Ni(II)/Mn(II), Fe(III)/Cu(II)/Co(II)/Mn(II), Fe(III)/Cu(II)/Ni(II)/Cd(II), Yb(III)/Eu(III), Sc(III)/Y(III),Sc(III)/Yb(III)/Dy(III) and Nb(V)/Yb(III)/Ho(III) has been achieved, among others.This work was supported by C.N.R. of Italy.     

稀土配合物研究 II: 1,6-双(1'-苯基-3'-甲基-5'-氧代吡唑-4'-基)-1,6-己二酮与钐(III)、铕(III)、铽(III)、镝(III)固体配合物的合成及性质研究

本文合成了1,6-双(1'-苯基-3'-甲基-5'-氧代吡唑-4'-基)-1,6-己二酮与Sm(III),Eu(III), Tb(III), Dy(III)的固体配合物, 并对他们的某些性质进行了研究.     

The mass spectra of 1,1,1-trichloro-2,4-pentanedione and its Al(III), Cr(III), Fe(III), Mn(II), Co(II) and Cu(II) complexes

The compounds 1,1,1-trichloro-2,4-pentanedione, Cu(II)tca₂, Co(II)tca₂, Mn(II)tca₂, Al(III)tca₃, Cr(III)tca₃ and Fe(III)tca₃ (tca?1,1,1-trichloro-2,4-pentanedionato, [CCl₃COCHCOCH₃]^?) have been prepared and their mass spectra have been obtained. The mass spectral results have been compared with findings for comparable fluorinated and nonhalogenated compounds. Comparisons are made in terms of internal redox reactions and hard and soft acid base theory. Rearrangement of chloride from ligand to metal accompanied by the elimination of CO or other neutral even electron fragments emerges as an important reaction for the ions of these compounds. While the internal redox reactions characteristic of all previous β-diketonate complex mass spectra still occur, their importance appears reduced to some degree by the facility of the chlorine rearrangement.     

Salisaldehyde-2-aminobenzimidazole schiff base complexes of Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II)

New metal complexes of Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) with salicylidine-2-aminobenzimidazole (SABI) are synthesized and their physicochemical properties are investigated using elemental and thermal analyses, IR, conductometric, solid reflectance and magnetic susceptibility measurements. The base reacts with these metal ions to give 1:1 (Metal:SABI) complexes; in cases of Fe(III), Co(II), Cu(II), Zn(II) and Cd(II) ions; and 1:2 (Metal:SABI) complexes; in case of Ni(II) ion. The conductance data reveal that Fe(III) complex is 2:1 electrolyte, Co(II) is 1:2 electrolyte, Cu(II), Zn(II) and Cd(II) complexes are 1:1 electrolytes while Ni(II) is non-electrolyte. IR spectra showed that the ligand is coordinated to the metal ions in a terdentate mannar with O, N, N donor sites of the phenloic -OH, azomethine -N and benzimidazole -N3. Magnetic and solid reflectance spectra are used to infer the coordinating capacity of the ligand and the geometrical structure of these complexes. The thermal decomposition of the complexes is studied and indicates that not only the coordinated and/or crystallization water is lost but also that the decomposition of the ligand from the complexes is necessary to interpret the successive mass loss. Different thermodynamic activation parameters are also reported, using Coats-Redfern method. This revised version was published online in July 2006 with corrections to the Cover Date.     

Preparation and characterization of Cr(III), Mn(II), Fe(II), Co(II) and Ni(II) complexes of a hexaazadithiophenolate macrocycle

The ligating properties of the 24-membered macrocyclic dinucleating hexaazadithiophenolate ligand (L(Me))2- towards the transition metal ions Cr(II), Mn(II), Fe(II), Co(II), Ni(II) and Zn(II) have been examined. It is demonstrated that this ligand forms an isostructural series of bioctahedral [(L(Me))M(II)2(OAc)]+ complexes with Mn(II) (2), Fe(II) (3), Co(II) (4), Ni(II) (5) and Zn(II) (6). The reaction of (L(Me))2- with two equivalents of CrCl2 and NaOAc followed by air-oxidation produced the complex [(L(Me))Cr(III)H2(OAc)]2+ (1), which is the first example for a mononuclear complex of (L(Me))2-. Complexes 2-6 contain a central N3M(II)(mu-SR)2(mu-OAc)M(II)N3 core with an exogenous acetate bridge. The Cr(III) ion in is bonded to three N and two S atoms of (L(Me))2- and an O atom of a monodentate acetate coligand. In 2-6 there is a consistent decrease in the deviations of the bond angles from the ideal octahedral values such that the coordination polyhedra in the dinickel complex 5 are more regular than in the dimanganese compound 2. The temperature dependent magnetic susceptibility measurements reveal the magnetic exchange interactions in the [(L(Me))M(II)2(OAc)]+ cations to be relatively weak. Intramolecular antiferromagnetic exchange interactions are present in the Mn(II)2, Fe(II)2 and Co(II)2 complexes where J = -5.1, -10.6 and approximately -2.0 cm(-1) (H = -2JS1S2). In contrast, in the dinickel complex 5 a ferromagnetic exchange interaction is present with J = +6.4 cm(-1). An explanation for this difference is qualitatively discussed in terms of the bonding differences.     

Thermal study of chelates of Co(II), Cu(II), Ni(II), Cr(III), Mo(III), and Fe(III) with bis(acetylacetone)ethylenediimine on activated silica gel surface

The divalent copper, nickel, cobalt and trivalent chromium, molybdenium and iron chelate compounds derived from bis(acetylacetone) ethylenediimine were grafted on activated silica gel using a batch process in methanolic solution. The sequence of the maximum retention capacity was Cr(III)>Mo(III)>Fe(III)>Co(II)>Ni(II)>Cu(II). Calorimetric titration was employed to study the interaction of activated silica gel with these series of metal chelate compounds. Exothermic enthalpic results were obtained throughout all interactions process. The spontaneity of these systems was reflected in negative and positive free Gibbs energy from entropic values.     

Thermal stability and photostability of water solutions of sulfophthalocyanines of Ru(II), Cu(II), Ni(II), Fe(III) and Co(II)

The thermal and photochemical stabilities were investigated for tetrasulfophthalocyanines of Cu, Co, Ni, Fe and Ru (MPcS) and for two monosulfophthalocyanines of Ru, either without (RuPcS1) or with the coordination of two units of DMSO in apical positions ([RuPcS1(DMSO)₂]DMSO). The thermal degradation of all of the studied complexes never showed the formation of spectroscopically detectable intermediates. CuPcS was the most stable complex, while all of the Ru-sulfophthalocyanines were particularly prone to thermal degradation. Photodegradation showed a better selectivity, and as with thermal degradation, the order of reactivity goes from the most stable CuPcS, to the least stable Ru-sulfophthalocyanines (RuPcS, RuPcS1 and [RuPcS(DMSO)₂]DMSO). In particular, when the RuPcS complex was irradiated, a stable intermediate was detected that had an absorption band at 532 nm and a mass spectrum attributable to the tetrasulfophthalocyanine from oxidative ring cleavage by the action of the singlet oxygen formed via ¹*RuPcS photosensitization. The most probable molecular formula demonstrates a new complex, with a cleaved ring containing an -NO group and two -OH groups that are all bonded at the two extremities of the open-chain molecule.     

Synthesis, investigation and spectroscopic characterization of piroxicam ternary complexes of Fe(II), Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) with glycine and DL-phenylalanine

The ternary piroxicam (Pir; 4-hydroxy-2-methyl-N-(2-pyridyl)-2H-1,2-benzothiazine-3-carboxamide 1,1-dioxide) complexes of Fe(II), Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) with various amino acids (AA) such as glycine (Gly) or DL-phenylalanine (PhA) were prepared and characterized by elemental analyses, molar conductance, IR, UV-Vis, magnetic moment, diffuse reflectance and X-ray powder diffraction. The UV-Vis spectra of Pir and the effect of metal chelation on the different interligand transitions are discussed in detailed manner. IR and UV-Vis spectra confirm that Pir behaves as a neutral bidentate ligand coordinated to the metal ions via the pyridine-N and carbonyl group of the amide moiety. Gly molecule acted as a uninegatively monodentate ligand and coordinate to the metal ions through its carboxylic group, in addition PhA acted as a uninegatively bidentate ligand and coordinate to the metal ions through its carboxylic and amino groups. All the chelates have octahedral geometrical structures while Cu(II)- and Zn(II)-ternary chelates with PhA have square planar geometrical structures. The molar conductance data reveal that most of these chelates are non electrolytes, while Fe(III)-Pir-Gly, Co(II)-, Ni(II)-, Cu(II)- and Zn(II)-Pir-PhA chelates were 1:1 electrolytes. X-ray powder diffraction is used as a new tool to estimate the crystallinity of chelates as well as to elucidate their geometrical structures.     

SYNTHESIS AND CHARACTERIZATION OF Fe(III), Co(III), Cu(II) AND Zn(II) COMPLEXES OF N-2,4-HYDROXYBENZAL-D-GLUCOSAMINE

Abstract

The Schiff base N-2,4-dihydroxybenzal-D-glucosamine (L), and its Fe(III), Co(III), Cu(II) and Zn(II) complexes have been synthesized and characterized. Magnetic moments suggest that all complexes are high-spin. The Cu(II) chelate in DMF solution has a distorted tetrahedral structure, as shown by ESR and electronic spectra. Detailed studies have been made concerning the solution equilibrium of L with transition metal ions. Stabilities of the complexes are in accord with the Irving-Williams series.     

A series of new pyridine carboxamide complexes and self-assemblies with Tb(III), Eu(III), Zn(II), Cu(II) ions and their luminescent and magnetic properties

In this study, we present eight new complexes and self-assemblies of Tb(III), Eu(III), Zn(II) and Cu(II) ions with novel pyridine carboxamides, L1 [methyl 4-methyl-3-(pyridine-4-carbonylamino)benzoate] and L2 [methyl 2-methyl-3-(pyridine-4-carbonylamino)benzoate], as heterocyclic ligands. Two luminescent and spatially organized coordination compounds were obtained with the use of the solvothermal synthesis method, (1) [Tb₃(L1)₄(BTC)₃(H₂O)₃] (where BTC is benzene-1,3,5-tricarboxylic acid) and (5) [Eu(L2a)₃(H₂O)₃](H₂O)₄. As a result of one pot reaction synthesis under reflux the d-electron metal ions and self-organization of ligands gave complexes (2) [Zn(L1)₂Cl₂], (3) [Cu(L1)₂(SCN)₂(H₂O)], (4) [Cu(L1)₂Cl₂], hybrid salt (6) [(CuCl₄)^2-(L2b)₂²⁺](H₂O), (7) [Cu(L2)₂Cl₂] and 1D-chain coordination polymer (8) [Cu(L2)₂(SCN)₂]. Identification of the obtained compounds was performed on the basis of the excitation, emission, ¹H NMR, FT-IR spectra, luminescence lifetimes, SEM images, PXRD, single-crystal X-ray diffraction, MS, TGA and elemental analysis. Selected compounds were also analyzed in terms of their potential magnetic properties.     

Synthesis and characterization of oxazolone complexes with Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) in different counterions

Oxazolone forms (1:1) complexes with Fe²⁺, Co²⁺, Ni²⁺, Cu²⁺ and Zn²⁺ chlorides, as well as forms (1:1) complexes with Co²⁺ and Cu²⁺ acetates. All the complexes are found to be non-electrolytes in DMF; tetrahedral, square-planar and octahedral structures are assigned to them based on electronic and magnetic data. IR studies reveal that the complexes are formed by donating the lone-pair electron from O and N atoms to the metal ion. The thermal decomposition of the [ML·mX·nH₂O]_y·H₂O chelates was studied by TG–DTA techniques. The mechanism of the decomposition has been established from TG–DTA data. The kinetic parameters, activation energy (E_a) and pre-exponential factor (A), were calculated from TG curves using Coats and Redfern method. Relative thermal stabilities of the chelates have been evaluated on the basis of these parameters.     

Spectroscopic,Magnetic and Thermal Investigations on Cu(II), Mn(II), Co(II) and Fe(III) Complexes with Glutamyl Nitroanilide

New complexes CuL₂×2H₂O, CoL₂×3H₂O, MnL₂×2H₂O and FeL₃×2H₂O, L=γ-L -glutamyl-5-(p-nitroanilide), were synthesized and characterized by their spectral, magnetic and thermal properties. The thermal stabilities of the synthesized complexes were examined in the temperature range 20–500°C. In all these complexes γ-L -glutamyl-5-(p -nitroanilide) acts as a bidentate ligand, its coordination involving the carbonyl oxygen and the nitrogen atom of the second amino group. The local structure around the Cu(II) ion is pseudotetrahedral. In the Co(II), Mn(II) and Fe(III) complexes, the metal ions are in the high-spin form, with octahedral stereochemistry. This revised version was published online in August 2006 with corrections to the Cover Date.     

Dinuclear triple helical Mn(III), Fe(III) and Co(III) complexes

Synthesis, characterization and physical properties of the dinuclear triple helical complexes [Mn₂(μ-L)₃] (1), [Fe₂(μ-L)₃] (2) and [Co₂(μ-L)₃] (3) with the tetradentate Schiff base (H₂L) derived from 1 mol equiv. of hydrazine and 2 mole equiv. of 2-hydroxy-1-naphthaldehyde are described. Triple helical molecular structures of 2 and 3 have been confirmed by X-ray crystallography. Magnetic susceptibility measurements reveal complex 3 is diamagnetic while a weak antiferromagnetic interaction is operative between the metal centres in both 1 and 2.     

Quantum efficiency of the luminescence of Eu(III), Tb(III) and Dy(III) in aqueous solutions

Summary The luminescence quantum efficiency of Eu(III), Tb(III) and Dy(III) in chloride solutions as well as complexed by aminopolyacetic acids was determined. An interpretation of the observed dependences in the system investigated has been proposed.

---

Die Lumineszenz-Quantenausbeute von Eu(III), Tb(III) und Dy(III) in wäßrigen Lösungen

Zusammenfassung Die Lumineszenz-Quantenausbeute von Eu(III), Tb(III) und Dy(III) in Chloridlösung und in Komplexen mit Aminopolyessigsäuren wurde bestimmt. Eine Interpretation der beobachteten Abhängigkeiten im untersuchten System wurde vorgeschlagen.

     

Extraction of Mn(II), Co(II), Cr(III) and Fe(III) from succinic acid medium by high molecular weight amines

The extraction behavior of Mn(II), Co(II), Cr(III) and Fe(III) has been studied in high molecular weight amines from succinic acid medium. The effect of different variables, like, type of amine, effect of pretreatment of amine with various acids, type of diluent and concentration of metal, succinate, hydrogen ions and amine, has been investigated. Extraction of Cr(III) and Fe(III) species is proposed and some binary separations achieved.