Far-infrared and electronic spectra of some bis(ethylenediamine) and related complexes of copper(II) and the relevance of these data to tetragonal distortion and bond strengths

Lever, A. B. P.; Mantovani, E.

doi:10.1021/ic50098a031

Cited by 201 publications

(63 citation statements)

References 2 publications

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“…[34] The far infrared region includes vibrations arising from coordination of the metal to the ligand. In far-IR ( Figures 13S-15S), it can be seen the appearance of the absorption bands characteristic for the new created metal-ligand bonds at 370 and 397 cm −1 (Cu-N), 384 and 417 cm −1 (Co-N) and 384 and 424 cm −1 (Zn-N) [31,[34][35][36] (Figure 12Sd). These observations support the hypothesis that metal ions are complexed through both nitrogen atom types from azomethine group and oxadiazole ring.…”

Section: Complexationmentioning

confidence: 99%

A silicon-containing polyazomethine and derived metal complexes: synthesis, characterization, and evaluation of the properties

Zaltariov¹,

Cazacu²,

Shova³

et al. 2014

Designed Monomers and Polymers

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A new dialdehyde-containing silicon was prepared by a reaction of Williamson-type and structurally characterized. By its subsequent condensation with 2,5-bis(p-aminophenyl)-1,3,4-oxadiazole, a multifunctional polyazomethine-containing imine, phenylene, oxadiazole, ether, and carbosilane groups within the chain was prepared. The complexes of this polymer with Co(II), Cu(II), and Zn(II) ions formed on the basis of electron-donor ability of the oxadiazole and azomethine groups were prepared in a one-step approach by mixing the two precursors of polyazomethine (dialdehyde and diamine) with corresponding metal salt. The ligand and metal complexes were characterized by spectral (Fourier transform infrared (FTIR), 1 H, and 13 C NMR) methods. The thermal, optical, electrochemical, and dielectric properties were studied and the effects of the metal insertion in dependence on its nature over these properties were evaluated. All compounds are soluble in common organic solvents and show low glass transitions due to the flexible ether and Si-C bonds, are fluorescent, mainly due to the oxadiazole ring, are redox active and have high dielectric constant due to the presence of oxadiazole, azomethine metal units.

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Section: Complexationmentioning

confidence: 99%

A silicon-containing polyazomethine and derived metal complexes: synthesis, characterization, and evaluation of the properties

Zaltariov¹,

Cazacu²,

Shova³

et al. 2014

Designed Monomers and Polymers

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“…The discussion follows that developed for the copper(I1) complexes of the same general formula (2,3). However, whilst the axial bonds in the very strongly tetragonally distorted copper complexes did not in general give rise to metalaxial ligand vibrational absorption above 200 cm-', this will not necessarily be the case in the cobalt(I1) and nickel(I1) complexes, where the tetragonal distortion may be less marked.…”

Section: Resultsmentioning

confidence: 94%

“…If the earlier assignment (17) is accepted then this lower energy metal sensitive band must be assigned to a bending mode, to a metal -axial ligand mode or to a ligand mode coupled with motion of the metal. These possibilities seem excluded since in the octahedral complexes bending modes are not expected at such a high frequency (2,16,17) and the lower energy band is insensitive to replacement of the axial ligand. Finally this band is isotopically sensitive in every copper and nickel complex so studied; if the band in question Can.…”

Section: Discussionmentioning

confidence: 99%

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Isotopic Studies of the Metal–Ligand Bond. Part III. The Far Infrared Spectra of Some Tetragonal Diamine Complexes of Cobalt(II) and Nickel(II): Studies of the Metal–Nitrogen Bond, as a Function of Metal Ion and of Spin State

Lever¹,

Mantovani²

1973

Can. J. Chem.

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The far infrared spectra of 35 complexes of the formula M(diamine),X, are reported where M = Co(I1) and Ni(II), X = C1-, Br-, I-, NO3-, SCN-, C104-, and AgIZ-and the diamine is ethylenediamine or its N,N-symmetric or antisymmetrically substituted dimethyl or diethyl derivative. Isotopic substitution studies with 62Ni and with are carried out with eleven characteristic complexes and assignments for the metal-nitrogen modes in both octahedral and square planar complexes so deduced. In most cases the appropriate number of metal-ligand modes, based on symmetry considerations, are observed. The variations in observed M-N frequencies are discussed in terms of the electronic and geometric factors previously utilized for the corresponding copper(I1) complexes. In complexes containing the asymmetric ligands, stretching vibrations arising from the two types of metal-nitrogen bond can be separately identified. Isotopic studies of pairs of complexes containing the same ligand and metal ion but with the latter in alternate spin states are reported here for the first time. All of the cobalt(I1) complexes and several of the nickel(I1) con~plexes are reported here for the first time.Les spectres dand l'infrarouge lointain de 35 complexes de formule M (diamine),X, ont etC rapportds, avec M = Co(I1) et Ni(II), X = C1-, Br-, I -, NO3-, SCN-, ClO4-, et Ag1,-et la diamine est 1'6th~-lenediamine ou ses derives N,N-dimethyles ou N,N-diethylis, symetriquement ou antisymetriquenlent substitues. Les etudes de substitution isotopique avec 62Ni et ,H ont etC effectuees sur onze complexes caracteristiques et les attributions sur les modes concernant la liaison metal-azote, a la fois pour les complexes octaedral et carre-plan, ont pu Ctre deduites. Dans la plupart des cas, le nombre approprie de modes relatifs au nlCta1-ligand bask sur des considerations de symetrie, a pu 6tre observe. Les variations dans les frequences M-N observees ont Cte discutees par rapport aux facteurs electroniques et gComCtriques precedemment utilises pour les complexes de cuivre(I1) correspondants. Dans les complexes comprenant des ligands asymktriques, les vibrations d'elongation qui sont dues aux deux types de liaison metal-azote ont pu 6tre separement identifiees. Les etudes isotopiques portant sur les paires de complexes contenant le mCme ligand et le mCme ion metal, ce dernier se trouvant dans des Ctats de spin alternes, ont etk rapportees ici pour la premiere fois. TOLE les complexes de cobalt(I1) et plusieurs complexes de nickel(I1) ont Bte decrits ici pour la premiere fois.[

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“…The data in Table 3 reveal that for a given ligand there is slight red shift of the d-d maximum in the case of squareplanar terminally coordinated chloro and bromo complexes (2) and (5). This indicates that these halogeno complexes are somewhat weaker in-plane donating ligands [38] than the corresponding four-coordinated complexes (6), (9), (10), (11) and (12) in the squareplanar environment. There is a correlation between the electronic and vibrational data, such as the in-plane bond strength decreases both the in-plane metal ligand stretching frequencies m(Cu-N) and the electronic transition frequency decreases.…”

Section: Electronic Absorption Spectramentioning

confidence: 93%

Synthesis, characterization and ascorbic acid oxidase mimetic catalytic activity of copper(II) picolyl hydrazone complexes

El-Motaleb

Ramadan

Issa

2005

Transition Met Chem

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Four new picolyl hydrazones were prepared via Schiff-base condensation of picolonic acid hydrazide with a-formyl-(L 1 ), a-acetyl-(L 2 ), a-benzoyl-(L 3 ) pyridine and a-formyl-(L 4 ) thiophene. Copper(II) complexes of these hydrazones and a series of copper(II) complexes containing (L 2 ) and various anions (Cl, Br, NO 3 , SCN, SO 4 , ClO 4 , AcO, PF 6 and BF 4 ) have been synthesized. Elemental, thermal analysis, molar conductivity, magnetic moment measurements and spectral (i.r., electronic and e.s.r.) studies have been used to characterize the prepared compounds. The overall structure and reactivity of the reported copper(II) chelates critically depend on the ligand structure and the nature of counter anion incorporated in the complex molecule. Octahedral [complex (7)], square-pyramidal [complex (8)] and square-planar monomeric species [complexes (1-6), (9) and (10)] and a dimeric structure with oxygen bridge in square-planar geometry [complexes (11) and (12)] were suggested. The reported copper(II) complexes exhibit promising oxidase catalytic activity towards the aerobic oxidation of vitamin C. A linear correlation exists between the oxidase catalytic activity and the Lewis-acidity of the central copper(II) ion created by the donating properties of the parent ligand, as well the irregularity of the coordination environment. The probable mechanistic implications of the catalytic oxidation reactions are discussed.

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Far-infrared and electronic spectra of some bis(ethylenediamine) and related complexes of copper(II) and the relevance of these data to tetragonal distortion and bond strengths

Cited by 201 publications

References 2 publications

A silicon-containing polyazomethine and derived metal complexes: synthesis, characterization, and evaluation of the properties

A silicon-containing polyazomethine and derived metal complexes: synthesis, characterization, and evaluation of the properties

Isotopic Studies of the Metal–Ligand Bond. Part III. The Far Infrared Spectra of Some Tetragonal Diamine Complexes of Cobalt(II) and Nickel(II): Studies of the Metal–Nitrogen Bond, as a Function of Metal Ion and of Spin State

Synthesis, characterization and ascorbic acid oxidase mimetic catalytic activity of copper(II) picolyl hydrazone complexes

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