ChemInform Abstract: DIPOLE-MOMENT MEASUREMENTS ON METAL CHELATE COMPLEXES PART 1, DIPOLE-MOMENT AND DIELECTRIC-RELAXATION MEASUREMENTS ON SQUARE-PLANAR AND OCTAHEDRAL METAL COMPLEXES OF SEVEN MERCAPTO-BETA-DIKETONES

Homobinuclear metal chelate complexes having 1,4-dihydroxy-9,10-anthracenedione (quinizarin) as a bridging unit have been prepared with four bivalent first row transition elements, namely cobalt, nickel, copper, and zinc. The coordination spheres of the metal ions consist of two nearly equivalent six-membered rings with oxygen donor atoms derived from the quinizarin and the terminal ligands which are either β-diketones or salicylic aldehyde. TG, spectroscopic (ir, uv–vis, epr), and magnetic measurements have been applied to an investigation of the geometry adopted by the MO4 chromophores. The results are consistent with varying degrees of distortion from the ideal square planar toward a tetrahedral arrangement around the metal ions, closely related to the specific metal center involved.

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AlPO4 Molecular Sieves Modified with Metal Chelate Complexes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19920774 ◽

1992 ◽

Vol 57 (4) ◽

pp. 774-780 ◽

Cited By ~ 19

Author(s):

Stanisłav Kowalak ◽

Kenneth J. Balkus

Keyword(s):

Ion Exchange ◽

Metal Complexes ◽

Molecular Sieves ◽

Metal Chelate ◽

New Method ◽

Cyclohexene Oxidation ◽

Chelate Complexes ◽

Pore System ◽

Catalytic Applications ◽

Exchange Properties

A new method for modification AlPO4 molecular sieves has been presented. Lack of ion-exchange properties makes the modification of aluminium phosphates for catalytic applications difficult. We have developed a method that involves the crystallization of AlPO4 molecular sieves around metal complexes. This results in encapsulation of the complexes within the intracrystalline pore system. Several metallophthalocyanines have been successfully encapsulated into AlPO4-5 and subsequently tested as catalysts for cyclohexene oxidation. Significant differences in activity result from the presence of different metallophthalocyanines.

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Metallkomplexe von N-(Pyrrol-l-yl)salicylaldiminen und deren Strukturbestimmung mittels Röntgendiffraktometrie und Röntgenabsorptionsspektroskopie (XANES) / Metal Chelates of N -(Pyrrol-l-yl)salicylaldim ines and their Structure D eterm ination by X-Ray Structure Analysis and X -R ay Absorption Spectroscopy (XANES)

Zeitschrift für Naturforschung B ◽

10.1515/znb-1996-0601 ◽

1996 ◽

Vol 51 (6) ◽

pp. 757-764 ◽

Cited By ~ 7

Author(s):

A. Bach ◽

L. Beyer ◽

T. Gelbrich ◽

K. H. Hallmeier ◽

C. Hennig ◽

...

Keyword(s):

Structure Analysis ◽

Absorption Spectroscopy ◽

Line Shape ◽

Metal Chelate ◽

Molecular Structures ◽

Chelate Complexes ◽

X Ray ◽

3D Metals ◽

Square Planar ◽

X Ray Absorption

Abstract A series of three N-(pyrrol-l-yl)salicylaldim ines 1-3 has been prepared an d characterized. Their metal chelate complexes with Cu, Ni and Co are described. The molecular structures of bis[N-(pyrrol-l-yl)salicylaldim inato]copper(lI) la, bis{N-[3-(pyrrol-l-yl)propyl]- salicylaldiminato}nickel(II) 2b and tris{N-[3-(pyrrol-l-yl)propyl]salicylaldiminato}cobalt(III) 2d were determined by X-ray structure analysis. The chelates with tetracoordinated copper and nickel show a square planar coordination with the characteristic trans configuration. The chelate with hexacoordinated cobalt has a meridional coordination sphere. The complexes have also been investigated by X-ray absorption spectroscopy (X̲-ray A̲bsorption N̲ear E̲dge S̲tructure, XANES) at the K edges of the 3d metals. Analyzing the relative intensities of the Is → 3d prepeak and the K edges of the line shape, it was possible to distinguish between planar, tetrahedral and octahedral coordination of the chelates

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