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Uses of Metal Complexes

While certain TSILs have been developed to pull metals into the IL phase, others have been developed to keep metals in an IL phase. The use of metal complexes dissolved in IL for catalytic reactions has been one of the most fruitful areas of IL research to date. LLowever, these systems still have a tendency to leach dissolved catalyst into the co-solvents used to extract the product of the reaction from the ionic liquid. Consequently, Wasserscheid et al. have pioneered the use of TSILs based upon the dissolution into a conventional IL of metal complexes that incorporate charged phosphine ligands in their stmctures [16-18]. These metal complex ions become an integral part of the ionic medium, and remain there when the reaction products arising from their use are extracted into a co-solvent. Certain of the charged phosphine ions that form the basis of this chemistry (e.g., P(m-C6H4S03 Na )3) are commercially available, while others may be prepared by established phosphine synthetic procedures. [Pg.37]

This paper reviews the recent studies in the field of radical reactions of organobromine compounds. A special attention is paid to the use of metal-complex systems based on iron pentacarbonyl as catalysts this makes it possible to perform the initiation and chain transfer reactions selectively at C-Br bond. [Pg.180]

The use of metal-complex initiating systems proved to be especially promising in carrying out the reactions with acrylic monomers which can be easily polymerized, when the common initiators of radical reactions are excepted. The use of Fe(CO)s -I- DMFA system allows us to perform homolytical addition of bromoform to acrylic monomers selectively at C-Br bond with no essential polymerization (ref. 10). [Pg.186]

The reductive carbonylation has an advantage of low feedstock cost. A wide range of homogenous metal complexes have been tested for both reactions (1-16). The major drawback of the use of metal complex catalysts is the difficulty of catalyst recovery and purification of the reaction products (12). In addition, the gaseous reactants have to be dissolved in the alcohol/amine mixture in order to have an access to the catalyst. The reaction is limited by the solubility of the gaseous CO and 02 reactants in the liquid alcohol reactant (17). [Pg.472]

The use of metal complex dyes for textile and related applications has already been treated comprehensively.7 There have been few major advances since that review. Therefore, this section focuses on typical commercial metal complex dyes, key structure-property relationships, and some recent studies on metal complex azo pigments. [Pg.557]

PHARMACODYNAMIC USES OF METAL COMPLEX DRUGS 9.18.5.1 Lithium Carbonate... [Pg.832]

Up to this point, we have discussed the use of metal complexes in assay and imaging. It remains to consider how they can be used as sensors analogous to those described at the beginning of this chapter. [Pg.939]

The use of metal complexed heterocyclic polyenes in these cycloadditions has also proven useful, as both the 1,1-dioxythiepine and azepine derivatives 250 and 253 took part in [6 + 4]- and [6+ 2]-photocycloadditions, respectively, to afford good yields of the... [Pg.315]

In 1981, it was demonstrated (70) that anions of nitro compounds can be involved in C,C-coupling with allyl acetates at the allylic carbon atom with the use of metal complex catalysis. For many years, this observation did not come to the attention of chemists interested in the synthesis of cyclic nitronates. However, Trost demonstrated (71) that this process can be used in the synthesis of five-membered cyclic nitronates from olefins (18) containing two acyl groups in the different allylic positions (Scheme 3.21). [Pg.451]

Leather can be dyed with acid, direct and mordant dyes. Many of the direct dyes were based on benzidine and its congeners but the German Ordinance, covered under the toxicity of certain azo dyes in section 2.3.1.1, has meant that this is no longer an option. To improve the light fastness of the dyed leathers, 1 2 premetallised azo dyes have also been used, but once again the use of metal complex dyes is becoming less favoured. ... [Pg.108]

It seems likely that the future will see major developments in the use of metal complexes as bacteriocidal, viricidal, immunosuppressive, anti-arthritic and biocidal agents. One class of complexing agents that appears to have particular promise are the macrocyclic antibiotics, macrocyclic polyethers, polyamines and cryptates . In this group the ligand wraps around a metal ion to form a lipid-soluble complex... [Pg.210]

Coordination compounds have become very usable in medicine [361-364]. In this respect, use of metal complexes (mostly those of lanthanides) as diagnostic [365-367] and anticancer [368-370] media should be specially emphasized. Among the last complexes, the aminoplatinum-containing compounds play an important role, so the structural study of platinum complexes as a model of nucleobases [371] is a topic of renewed interest. The new issue of Comprehensive Coordination Chemistry II [372] contains a wide description of nanoparticles (vols. 6 and 7), biocoordination chemistry (vol. 8), and other aspects of application of coordination compounds. [Pg.361]

As a reversible protection measure, complexation with a Fe(CO)4 moiety appeared to be most promising. The monoene 68 was indeed found to react smoothly with Fe(CO)s at room temperature to give the tetracarbonyliron complex 73b in 75% yield after crystallization. The complex 73b proved to be stable for days in air as a solid and in solution (CHCl3, benzene), and its ligand 68 can be conveniently liberated under mild oxidative conditions [Ce(N03)4/ MeOH/THF] at room temperature (Scheme 14) [77]. Although the use of metal complexation as a protection method for such compounds with highly pyramidalized double bonds works well for the monoene 68 and the diene 70, the complexation of more highly unsatu-... [Pg.47]

The in situ deprotonation of an azolium salt to produce the desired NHC has the advantage that the carbene does not have to be isolated, thus simplifying the reaction workups when the aim is preparation of the metal complex. This avoids the handling of the free NHCs, which most of the times are air-and moisture-sensitive. Two types of azolium in situ deprotonation reactions can be found in the literature, depending on the deprotonation process employed (i) addition of an external base and (ii) use of metal complexes with basic ligands. [Pg.93]

The use of metal-complex mediators was applied by Nunnecke and co-authors (Nunnecke and Voss 1999) to the dechlorination of chlorinated benzenes and diben-zofurans. The main products were chlorobenzene and unsubstituted dibenzofurans, respectively. [Pg.295]

Only in recent decades has it become clear that inorganic molecule-based compounds can possess remarkable physical properties. These properties can be electrical, magnetic, or optical. One of the first typical examples is KCP (kalium tetracyanoplatinat, in German), K2[Pt(CN)4X0.3] /1H2O X = Cl, Br), which was prepared as early as 1842 (1, 2). This complex was shown to be a metal-like conductor more than a century later (3, 4). Likewise, but within a shorter period of time, the use of metal complexes of 1,2-dithiolene ligands (Scheme 1), first... [Pg.400]

Final purification by use of metal complexes was also applied in the syntheses of the ligands XS4—H4. These ligands exclusively contain thiolate donors and were prepared by Hahn et al. (23) using 2,3-dimercaptobenzoic acid as starting material (Scheme 8). Isopropyl or benzyl protection of the thiol functions, conversion into the acyl chlorides, reaction with a,oo-diamines, and deprotection of the sulfur atoms enabled the connection of two 1,2-benzene-dithiol units via carboxylic acid amide bonds. [Pg.595]

Several reviews describing the use of metal complexes as photochemical polymerization initiators have appeared. ... [Pg.3795]


See other pages where Uses of Metal Complexes is mentioned: [Pg.104]    [Pg.180]    [Pg.809]    [Pg.913]    [Pg.1066]    [Pg.178]    [Pg.41]    [Pg.198]    [Pg.172]    [Pg.264]    [Pg.335]    [Pg.100]    [Pg.75]    [Pg.64]    [Pg.37]    [Pg.327]    [Pg.85]    [Pg.135]    [Pg.47]    [Pg.141]    [Pg.11]    [Pg.348]    [Pg.337]    [Pg.113]    [Pg.71]    [Pg.195]   


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