Macromolecular metal complexes

The macromolecular metal complexes or ion-pair — — ML° might be hybrid phase catalysts, e.g. R425 ... 

In the early 1970 s, Bayer et al. reported the first use of soluble polymers as supports for the homogeneous catalysts. [52] They used non-crosslinked linear polystyrene (Mw ca. 100 000), which was chloromethylated and converted by treatment with potassium diphenylphosphide into soluble polydiphenyl(styrylmethyl)phosphines. Soluble macromolecular metal complexes were prepared by addition of various metal precursors e.g. [Rh(PPh3)Cl] and [RhH(CO)(PPh3)3]. The first complex was used in the hydrogenation reaction of 1-pentene at 22°C and 1 atm. H2. After 24 h (50% conversion in 3 h) the reaction solution was filtered through a polyamide membrane [53] and the catalysts could be retained quantitatively in the membrane filtration cell. [54] The catalyst was recycled 5 times. Using the second complex, a hydroformylation reaction of 1-pentene was carried out. After 72 h the reaction mixture was filtered through a polyamide membrane and recycled twice. 

Main Structural Principles of Macromolecular Metal Complexes. 56... 

Keywords Sonogashira polycondensation Hybrid polymers Polypyridine ligands Copolymers Macromolecular metal complexes... 

Macromolecular metal complexes can be classified into three main categories, taking into consideration the manner of binding of a metal compound to suitable macroligands [33] (Fig. 1). Type 1 metal complexes are those with the metal ion or metal chelate at a macromolecular chain, network, or surface. One possible approach to synthesize such polymers is using the polymerization of vinyl-substituted metal complexes. 

Type 2 metal complexes have the macromolecular metal complex as part of a polymer chain via the metal or the ligand. Different methods for their prepa-... 

Ciardelli F, Tsuchida E, Woerhle D (eds) (1996) Macromolecular metal complexes. Springer, Berlin Heidelberg New York... 

Tsuchida, E. 2000. Macromolecular-Metal Complexes. Wiley, New York. 

Techniques for the quantitative investigation of the dynamic processes involved, as well as of the physiochemical properties of macromolecular metal complexes, are... 

The Ru-red or Ru-brown complex adsorbed in the Nafion membrane is probably present in a microheterogeneous environment imposed by hydro-phobic cluster made of fluorocarbon moiety and by hydrophilic cluster made of sulfonate ions, and the Ru-red or Ru-brown is electrostatically held by the sulfonate ions. In a polymer membrane, the metal complex molecules would be isolated and the microheterogeneous environment would alter the complex-solvent interaction. Such effects are well characterized for macromolecular metal complexes . Since Ru-red and Ru-brown water oxidation catalysts are strong oxidants in their higher oxidation states, they would attack organic ligands of the... 

T. Matsumoto, S. Kotani, H. Yamaguchi. K. Shiina and K. Sonogashira, Preprint of Tokyo Seminar on Macromolecular Metal Complexes, 1987, Tokyo, 207. 

This book provides an overview of possible combinations of metal complexes and metals with organic and inorganic macromolecules (often also named macromolecular metal complexes — MMC [1]). This book covers the formation, synthesis, structure and properties of these exciting and relatively new materials. Metal-containing macromolecules are a fascinating field of science. It is readily understandable that materials with unusual properties are obtained by having a metal complex or metal as part of a macromolecule. Nature shows us the functions of such materials extremely well by the selectivity and activity of, for example, hemoglobin, photosynthesis and metalloenzymes. 

Type I A metal ion, metal complex or metal is bound to a chain of a linear or cross-linked organic or inorganic macromolecule via a covalent (at the metal), a coordinative (at the metal), a complex (at the ligand of a complex), an ionic or a 7i-bond (so-called Macromolecular Metal Complexes , Fig. 1-4). Additional possibilities exist for different kinds of binding at the surface of a carrier or the end group of a macromolecule. Examples are described in Chapters 4 and 5. 

Type II The ligand of a metal complex is part of a macromolecular chain or network (so-called Ligand Macromolecular Complexes , Fig. 1-5). Besides the direct synthesis of macromolecular metal complexes from low molecular precursors, a macromolecular ligand can be prepared first which is then metallated in a second step. Examples of this type are given in Chapter 6. 

Systematic studies of metal complexes and metals in macromolecules -often called macromolecular metal complexes [1] - have a short history of about sixty years. 

Today several summarizing reports exist in this field covering such themes as macromolecular metal complexes, organometallic polymers, metal-... 

An important use of polymer ligands is the extraction of trace amounts of metals, e.g. gold, uranium, from seawater. For example, an industrial extraction of uranium from seawater has been developed using polymers with amidoxime groups [76]. Also the role of macromolecular metal complexes in Green chemistry is very significant, for example their efficient use in the neutralization of effluents from chemical companies. 

The interaction of artificial metal ions/complexes with peptides/proteins [11], nucleic acids/DNA [12,13], enzymes [14], steroids [15] and carbohydrates [16] forms a bridge between natural and artificial macromolecular metal complexes. Biometal-organie chemistry concentrates on such complexes [17]. The reason for the increasing interest in this field lies in medical applications of metal complexes (cancer, photodynamic therapy of cancer, immunoassays, fluorescence markers, enantioselective catalysis, template orientated synthesis of peptides, etc.). Figure 2-4 presents an overview of metals in medicine [18]. Some examples are given below. 

Figure 2-9. A cartoon (taken from [21]) shows the steps in the construction of a macromolecular metal complex, (a) pyrrole, (b) porphyrin, (e) heme, (d) myoglobin, (e) hemoglobin.

Kinetics and Thermodynamics of Formation of Macromolecular Metal Complexes and Their Structural Organization... 

Chapter 3 concentrates on different aspects of the formation of macromolecular metal complexes (MMCs) by interaction of a macromolecular ligand with a metal compound MX . Such metal-containing macromolecules are classified in Section 1.2.1 as type I. Chapter 4 concentrates on polymerizations of metal-containing monomers. Examples of the binding of MX at macromolecular ligands are given in more detail in Chapter 5. The kinetics and thermodynamics of formation of macromolecular metal complexes of type II, type III and type rv are not known in detail. A few aspects are included in Chapters 6, 7 and 8. 

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