Modifizierung von Schichtsilicaten mit sterisch anspruchsvollen Metallkomplexen. 3. Synthese und Intercalation der planar‐quadratischen Komplexe [Cu(bppep)(H₂O)](ClO₄)₂ und [Ni(bppep)(Cl)Cl] (bppep = 2,6‐Bis[1‐phenyl‐1‐(pyridin‐2‐yl)ethyl]pyridin) in Hectorit

Abstract

Die Umsetzung von Na+(aq)‐Hectorit mit [Cu(bppep)(H2O)](ClO4)2 und [Ni(bppep)(Cl)]Cl führt zum Austausch der Na+(aq)‐Ionen gegen die Komplexkationen [Cu(bppep)(H2O)]2+ und [Ni(bppep)(Cl)]+. Zusätzlich werden die Kation‐Anion‐Paare [Cu(bppep)(H2O)](ClO4)2 und [Ni(bppep)(Cl)]Cl zwischen den Hectoritschichten intercaliert (Intersalation). Andererseits ist es möglich, [Cu(bppep)(H2O)]2+ oder [Ni(bppep)(H2O)]2+‐modifizierte Hectorite ohne zusätzliche Ionenpaar‐Intercalation (Intersalation) durch Reaktion der Cu2+ (aq)‐ und Ni2+ (aq)‐Hectorite mit dem bppep‐Ligand zu synthetisieren.

Coordination Chemistry of Tripyridinedimethane

“…The well-studied polypyridines, A, have a very rigid structure, limiting their coordination geometry on a metal. In contrast, the rarely studied polypyridinepolyalkanes 1,2 contain alkanediyl bridges between pyridine rings and therefore combine features of polyazaheterocycles with enhanced molecular flexibility. For example, they have the flexibility to adopt either meridional chelation (which is exclusive for polypyridines) or facial chelation, which is characteristic for trihetaryl-substituted methane or boronate.…”

Intracrystalline and Electronic Structures of Copper(II) Complexes Stabilized in Two-Dimensional Aluminosilicate

“…Various kinds of transition metal complexes with polyaza macrocyclic ligands − have received much attention due to their significant catalytic activities in electrochemical, biological, and photobiological processes. Such complexes have been successfully intercalated into the charged layer of host structures such as clay mineral by ion-exchange reaction, − and these intercalates have often exhibited efficient biomimetic catalytic properties comparable to those of the homogeneous solution containing the same amount of the metal complex. , In addition, many transition metal cationic porphyrins have been known to be stable against demetalation on clay surfaces, ,, and from several studies, it has been pointed out that the complex stability on clay surfaces may be different from that in solution. − It is expected that the electronic configuration, mobility, and orientation of the complex could be altered in the interlayer surface of clays. Therefore, the characterization of the chemical bonding nature as well as the local structure of transition metal ion within the charged layers has been one of the most attractive research problems.…”

“…However, the insufficiency in numbers and intensities of the observed (00l) reflections due to their lower dimensionality might make it impossible for the powder X-ray diffraction method to determine directly the geometry and ligand environment of the metal complex ion intercalated into clay material. In addition, even though nearly all the conceivable permutations have been proposed by means of spectroscopies such as IR, ,, UV−visible, , and EPR, ,,, it is still unclear how the intercalation of metal complex into the charged layer affects the changes in coordination of a transition metal and bonding character. In these points of view, X-ray absorption spectroscopy would be a useful tool to probe the metal ions absorbed in the interlayer, − because of its peculiar property of being sensitive to both structural and electronic evolutions in a specific atom due to its element selectivity and no requirement of long-range order in the crystal structure.…”

“…Various kinds of transition metal complexes with polyaza macrocyclic ligands [1][2][3][4][5][6][7] have received much attention due to their significant catalytic activities in electrochemical, biological, and photobiological processes. Such complexes have been successfully intercalated into the charged layer of host structures such as clay mineral by ion-exchange reaction, [8][9][10][11][12][13][14][15][16][17] and these intercalates have often exhibited efficient biomimetic catalytic properties comparable to those of the homogeneous solution containing the same amount of the metal complex. 18,19 In addition, many transition metal cationic porphyrins have been known to be stable against demetalation on clay surfaces, 15,17,20 and from several studies, it has been pointed out that the complex stability on clay surfaces may be different from that in solution.…”