Applications of metal complexes

Important aspects of the coordination chemistry of binary chalcogen-nitrogen ligands include (a) the ability of metals to stabilize labile neutral and anionic binary S-N ligands, (b) the applications of metal complexes as reagents for the preparation of other S-N compounds, and (c) the possible incorporation of metals into sulfur-nitrogen chains to produce conducting materials. 

Until recently the most popular method in asymmetric catalysis was the application of metal complexes. This is not surprising, since the use of different metals, ligands and oxidation states makes it possible to tune selectivity and perform asymmetric induction very easily. Thus, the concept of asymmetric catalysis has become almost synonymous with the use of metals coordinated by chiral ligands [1,2]. In many examples the metal is a Lewis acid [3]. 

Study of the polymer-metal complex is still a new field, and not all possible applications of metal complexes have been explored yet. Further demonstrations of new, unique applications of the polymer-metal complexes offering advantages over the conventional properties of both polymers and metal complexes are to be expected in the near future. 

The application of metal complexes as catalysts in various chemical and technological processes has been known for a long time. In this respect, we note a high interest displayed at present for the catalysis of hydroformylation [288-290], olefine... 

Even a relatively simple bacterial photosynthetic system is very complex and its synthetic imitation is a challenging task. Mimicking of the natural photosynthetic process requires synthetic models of all the crucial components and linking them together into a working molecular assembly. All the elements (antenna, charge separation, and reaction centres) may involve transition metals. Application of metal complexes facilitates mimicking of this complex chemical system due to rich and versatile photochemical processes typical for transition metal complexes (see section 6.4 in Chapter 6) [48]. 

In this chapter we review the application of metal complexes and light in the study of biological electron transfer events. 

Application of metal-complexing imprinted polymers as sensors for small gas molecules has been demonstrated by Borovik and co-workers [31]. Thus, a sensor... 

In our opinion, this development was facilitated mainly by two key factors the technical progress of all analytical methods, particularly in the fields of NMR spectroscopy and X-ray diffractometry, and the plenty of structural data meanwhile available for metal complexes of model compounds of carbohydrates. The basic research on the structural chemistry of the latter complexes followed by a transfer of the thereby gained knowledge in stability and regioselectivity of metal coordination into reducing carbohydrates has proved to be very successful. By this way, the improvement of existing and the development of new applications of metal complexes of carbohydrates, which provide a cheap and renewable feedstock, is merely a matter of time. 

Catalytic applications of metal complexes with secondary phosphines 262... 

Coordination chemistry and catalytic applications of metal complexes... 

In Chapter 11, Molecular Electron Transfer, the broad and deep field of electron-transfer reactions of metal complexes is surveyed and analyzed. In Chapter 12, Electron Transfer From the Molecular to the Nanoscale, the new issues arising for electron-transfer processes on the nanoscale are addressed this chapter is less a review than a toolbox for approaching and analyzing new situations. In Chapter 13, Magnetism From the Molecular to the Nanoscale, the mechanisms and consequences of magnetic coupling in zero- and one-dimensional systems comprised of transition-metal complexes is surveyed. Related to the topics covered in this volume are a number addressed in other volumes. The techniques used to make the measurements are covered in Section I of Volume 2. Theoretical models, computational methods, and software are found in Volume 2, Sections II and III, while a number of the case studies presented in Section IV are pertinent to the articles in this chapter. Photochemical applications of metal complexes are considered in Volume 9, Chapters 11-16, 21 and 22. 

Synthetic Applications of Metal Complexes, F. G. A. Stone, ibid., 1975,100, 257. 

OPTICAL AND LUMINESCENCE PROPERTIES AND APPLICATIONS OF METAL COMPLEX-BASED POLYMERS... 

Overall, the FID assay and the H-G crystallization strategy, either singly or in combination (26), can assist in circumventing the usual slow steps associated with the analysis of DNA-ligand binding. Elimination of these historically slow steps would no doubt accelerate the discovery process and perhaps lead to the increased development and application of metal complexes towards biomedically-significant problems. 

There is a vast and increasing literature on the formation, characterization, and practical applications of metallic complexes of phospholes. An excellent summary of the various types of complexes that can be prepared is provided in a review . Suffice it to say that complexation is a fundamental reaction of phospholes and has opened many pathways both in phosphole reaction chemistry and in coordination chemistry. In this section, only special reactions that occur with the phosphole moiety while in coordinated form are considered. Examples have, of course, already been encountered, as in the intramolecular form of Diels-Alder cycloadditions described in Section 2.15.5.4. Other important processes include ... 

Properties and Potential Applications of Metal Complexes and Metals in Macromolecules... 

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. 

Other Applications of Metal Complexes in Macromolecules with Small Molecule-Binding Abilities... 

It should be mentioned that simple metal complexes immobilized on polymer supports were initially used for polymerization (1965/1966) in the Solvay catalysts based on titanium complexes bound to macromolecular ligands with C=0, C=N and C=N groups. Until now the data are mainly available in patent literature, and there are few kinetic studies of polymerization processes involving the action of macromolecular complexes. At the same time the use of metal complexes bound to inorganic supports has been extensively developed in polymerization catalysis. This indicates that there has been inadequate study of the application of metal complexes immobilized on polymer supports to the catalysis of polymerization and copolymerization of different monomers, mainly olefins. 

Some therapeutic or diagnostic applications of metal complexes, thus excluding the mechanical use of metals in biomedical applications, are listed in Table 1. 

These and many other applications of metal complexes are exciting the imagination of research chemists and increasing the production potential and versatility of our chemical industry. In order to exploit the use of metal complexes, we need to know more about some of the details of the reaction processes. This chapter illustrates the approach to such problems and provides examples of information obtained and reaction theories proposed. 

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