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Pentadentate Ligands (pentadentate + ligand)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

A New Pentadentate Ligand Forms Both a Di- and a Mononuclear MnII Complex: Electrochemical, Spectroscopic and Superoxide Dismutase Activity Studies

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 28 2007
Federico Cisnetti
Abstract The X-ray crystal structure of the dinuclear complex[1(PF6)2] derived from a new ligand bearing both imidazole and phenolato moieties, namely N -(2-hydroxybenzyl)- N,N,-bis[2-(N -methylimidazolyl)methyl]ethane-1,2-diamine (LH), is described and its properties in organic solvent (CH3CN) investigated (EPR, electrochemistry). [1(PF6)2] is shown to be a mononuclear MnII species in aqueous solution and displays an efficient SOD-like activity, as measured by the McCord,Fridovich assay performed both in conventional phosphate buffer and in a noncoordinating buffer (PIPES). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source]

Pentadentate Ligands for the 1:1 Coordination of Lanthanide(III) Salts

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 3 2008
Markus Albrecht
No abstract is available for this article. [source]

Pentadentate Ligands for the 1:1 Coordination of Lanthanide(III) Salts,

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 20 2007
Markus Albrecht
Abstract Three hydrazone type ligands, namely 2 -H, 3, and 4, which were designed to form 1:1 complexes with lanthanoid(III) ions, are presented. Although the tetradentate ligand 2, leads to an interesting complex [(2)(2 -H)YCl2] with yttrium(III), a more general principle for the coordination of the metal ions by hydrazone-type ligands can be found with ligand 3, where 1:1 complexes are obtained with an effective coordination of the metal salts by the ligand. The stabledimer [{(3)Nd(CF3SO3)}2(,-CF3SO3)3]CF3SO3 was characterized by X-ray structure determination. Depending on the size of the metal ion, additional co-ligands can also be bound to the metal centers. This is observed in the molecular structures of [(3)Pr(NO3)2(MeOH)2](NO3), [(3)NdCl2(MeOH)(EtOH)]Cl, [(3)ErCl2(MeOH)]Cl, and [(3)LuCl2]Cl. The solid-state molecular structures of 4 and 4·HCl show the helicating ability of this ligand upon metal coordination. The corresponding lanthanide complexes of 4 are characterized by standard techniques such as NMR and CD spectroscopy and mass spectrometry.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source]

Crystallochemical formula as a tool for describing metal,ligand complexes , a pyridine-2,6-dicarboxylate example

ACTA CRYSTALLOGRAPHICA SECTION B, Issue 1 2009
Viktor N. Serezhkin
Compounds (299) containing 494 symmetrically independent pyridine-2,6-dicarboxylate moieties have been investigated. Among them the structures of Na3[Nd(Pydc)3]·14H2O and Na3[Er(Pydc)3]·11.5H2O, where H2Pydc is pyridine-2,6-dicarboxylic acid, were determined by single-crystal X-ray diffraction, while the others were taken from the Cambridge Structural Database. The characteristics of any complex by means of the `method of crystallochemical analysis' are described, and the coordination types of all the Pydc ions and crystallochemical formulae of all the compounds were determined. Although the ion can act as a mono-, bi-, tri-, tetra- and pentadentate ligand, 96% of Pydc ions are coordinated to the central A atom in the tridentate-chelating mode. The dependence of the denticity and geometry of pyridine-2,6-dicarboxylate, as well as of the composition of Pydc-containing complexes, was studied as a function of the nature of the A atom, the molar ratio Pydc:A and the presence of neutral or acidic ligands in the reaction mixture. [source]

A lariat-functionalized copper(II) di­imine,dioxime complex

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 12 2002
Salma Kiani
The dimeric title copper(II) complex, diaqua-1,O,2,O -bis[3,9-dimethyl-6-(2-pyridyl­methyl)-4,8-di­aza­undeca-3,8-di­ene-2,10-dione dioximato(1,)]-1k4N2,N4,N8,N10;1:2,5O2:N2,N4,N8,N10 -dicopper(II) diperchlorate, [Cu2(C17H24N5O2)2](ClO4)2, crys­tallizes with one Cu atom in a square-pyramidal environment and the other Cu atom displaying a distorted octahedral coordination. In each case, the four N atoms in the core of the ligand (two imine and two oxime N atoms) form the base of the pyramid, with a water mol­ecule at an apex. The two parts of the dimer are linked by an interaction [2.869,(2),Å] between one of the Cu atoms and one of the oxime O atoms coordinated to the second Cu atom, and also by a hydrogen bond between the apical water mol­ecule on the second Cu atom and the pyridyl N atom from the coordination sphere of the first Cu atom. The pyridyl N atoms of the lariat arms are not coordinated to either of the Cu atoms. Thus, this potentially pentadentate ligand is only tetradentate when coordinated to CuII. [source]