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Molecular coordination compounds

This established C-H chemistry in molecular coordination compounds should have its formal analog in metal surface chemistry. Carbon-hydrogen bond-cleavage is a common reaction at metal surfaces but it does not comprise mechanistically the simple collision of a hydrocarbon such as methane with a metal surface vide infra). Methane neither reacts with nor is chemisorbed on a metal surface under moderate conditions. However, propylene does chemisorb, and then C-H bonds may be broken, depending upon the nature of the metal surface. Generally, the sequence at the surface comprises first the formation of a coordinate bond between a surface metal atom(s) and some functionality in the... [Pg.274]

Examples briefly discussed here in which the coordination aspect is important have been chosen in order to emphasize the close ties between this kind of solid state compound, molecular coordination compounds and organic chemistry. Bonding in these materials was described purposely from a molecular viewpoint, regarding them as giant "metal complexes" in order to facilitate excursion of the molecular chemist in the realms of solid-state chemistry. [Pg.520]

The second area that has exploded during the last decade concerns materials that involve open-frameworks that are constructed from both inorganic and organic components we shall refer to them collectively as hybrid materials and wUl cover them in two separate sections. The first will examine the so-called coordination polymers [14] in which molecular coordination compounds are connected by organic linkers to form chains, sheets or 3-D networks. The second class involves extended metal-oxygen-metal networks that are decorated by organic ligands we shall refer to these as hybrid metal oxides. [Pg.590]

Molecular clusters have been considered for more than 20 years as models that help rationalize the reactions occurring on the active surface of heterogeneous catalysts. In fact, like metal surfaces, they contain several metal atoms bonded to each other and they can bind ligands through both polycentric and direct ligand-metal interactions. Moreover, as they are molecular coordination compounds, they are normally soluble in organic solvents, and we nowadays have powerful, readily available, spectroscopic tools (IR, NMR, etc.) for characterizing molecular species in solution. [Pg.715]

Most of the preparations of molecular coordination compounds of iron published in Inorganic Syntheses or elsewhere require the readily available pentacarbonyliron or derivatives thereof. However, pentacarbonyliron is a rather stable compound that needs either thermal or photochemical activation to react. We describe here the selective, high-yield, one-pot synthesis of the title complexes from potassium tetracarbonylhydridoferrate(l — ), easily generated from pentacarbonyliron, a method that can be referred to as a nucleophilic activation of pentacarbonyliron. ... [Pg.151]

The eight-fold coordination type with the ligands situated at the corners of a cube maximizes non-bonded repulsions (20, 58, 59,64), and it, therefore, is not an appealing coordination t 7pe. The cube is, indeed, unknown as a structure type among the molecular coordination compounds of the d-transition elements although it is prevalent among inonic compounds with the CaF2 and CsCl lattice types. [Pg.19]

Measurements on copper) I) chloride show the vapour to be the dimer of formula CU2CI2, but molecular weight determinations in certain solvents such as pyridine show it to be present in solution as single molecules, probably because coordination compounds such as py -> CuCl (py = pyridine) are formed. [Pg.415]

According to these basic concepts, molecular recognition implies complementary lock-and-key type fit between molecules. The lock is the molecular receptor and the key is the substrate that is recognised and selected to give a defined receptor—substrate complex, a coordination compound or a supermolecule. Hence molecular recognition is one of the three main pillars, fixation, coordination, and recognition, that lay foundation of what is now called supramolecular chemistry (8—11). [Pg.174]

Reedijk J, Fichtinger-Schepman AMJ, Oosterom AT van, Putte P van de (1987) Platinum Amine Coordination Compounds as Anti-Tumour Drugs. Molecular Aspects of the Mechanism of Action. 67 53-89 Rein M, see Schultz H (1991) 74 41-146... [Pg.253]

Konig and others published in the 1970s an impressive series of studies on six-coordinate iron(II)-bis-phenanthroline complexes [160-164] for which they inferred 5=1 from thorough magnetic susceptibility and applied-field Mossbauer measurements. Criteria for the stabilization of the triplet ground state for six-coordinate compounds with tetragonal ( >4 ) and trigonal ( >3 ) symmetry were obtained from LFT analyses [163], The molecular structures, however, were not known because the materials could not be crystallized. [Pg.428]

Application of coordination compounds in medicine, materials chemistry, and as catalysts are mentioned and are cross-referenced to a fuller discussion in Volume 9. Comment is made on application of complexes in nanotechnology, and on the molecular modeling of complexes. The material cannot be totally comprehensive because of space limitations, but is selected in such a way to give the most effective review of discoveries and new interpretations. [Pg.1295]

Reedijk, J., Fichtinger-Schepman, A.M.J., van Oosterom, A.T., and van de Putte, P. (1987) Platinum amine coordination compounds as anti-tumor drugs. Molecular aspects of the mechanism of action. Struct. Bonding (Berlin) 68, 53-72. [Pg.1106]


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See also in sourсe #XX -- [ Pg.5 , Pg.19 , Pg.27 , Pg.54 ]




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