Platinum complexes chemistry

Organonickel derivatives also offer cases of the -coordination of the substituted hydrotrisfpyrazol- l-yl)borate ligand. For the palladium and platinum complexes, the M(II) M(IV) (M = Pd, Pt) transformation is facile. Organopalla-dium chemistry offers anew type of agostic interactions, C—H - - - Pd, where the C—H bond belongs to one of the pyrazolate rings. Cyclopalladation of various pyrazol-l-ylborates and -methanes does not modify their structure. 

The chemistry of anti-tumour platinum complexes. A, I. Stetsenko, M. A. Presnov and A. L. Konovalova, Russ. Chem. Rev. (Engl Transl), 1981,50,353-367 (131). 

The chemistry of silylene-metal complexes has developed in quite another direction, however, from reactions of disilyl-metal complexes, leading to complexes of otherwise unstable disilenes such as Me2Si=SiMe2. Molybdenum and tungsten complexes have been particularly well investigated by Berry and co-workers,103 and platinum complexes have also been isolated.104 Readers interested in this field are directed to a 1992 review of silylene, silene, and disilene-metal complexes.105... 

A review17 with 25 references of five-coordination in palladium(II) and platinum(II) chemistry is presented. The complexes have invariably a trigonal bipyramidal geometry with the bidentate ligand and the alkene in the equatorial plane. 

The effects of the bifunctional Pt drugs are very like those of the cross-linking dialkylating agents known to be effective against cancer (90). The reader is reminded of the parallel chemistry of carbonium ions and of platinum complexes, section IIF. 

Rosenberg, B. Platinum Complexes for the Treatment of Cancer. Why the Search goes on. In Cisplatin Chemistry and Biochemistry of a Leading Anticancer Drug Lippert, B., Ed. Wiley-VCH New York, 1999 pp 3-30. 

Among the less common oxidation states those of I and III have the most significance. Complexes of platinum(III) have been of interest for many years because of their intermediacy in substitution reactions of platinum(II) and (IV). More recently binuclear platinum(I) and (III) complexes have been isolated, and the chemistry of these new complexes will be of increasing interest in platinum chemistry. Platinum forms strong homometallic bonds giving rise to multimetallic chain compounds and cluster complexes. The increasing use of X-ray crystallography, and 31P and 19 PtNMR will allow systematic studies to be made on these multimetallic platinum complexes. 

A recent review discusses the chemistry of ylides and their reactions with transition metal complexes.425 This article integrates platinum yhde chemistry with that of other metal ions, and has sections covering bonding. 

Again such complexes are more prevalent in palladium chemistry. Examples in platinum(II) chemistry are found with azobenzene, 121< 1216 N,A-dialkylbenzylamine,1217 benzoquin-oline,1218 8-methylquinoline,1218 acetophenone oxime1220 and N-alky 1-7V-nit rosoanilines.1221... 

A number of dppm complexes with hydride and methylene bridges have been referenced already in this chapter under the respective sections on hydrides and carbenes. These compounds will not be included again here. The binuclear platinum(I) chemistry of these complexes has also been developed. The complexes have a metal-metal bond between platinums, although this may be broken by formation of A-frame type molecules. This chemistry has been described in a series of papers, and the reaction types are outlined in Schemes 13 and 14, i28 .1438-1445 a similar chemistry will likely develop with the methylated ligand Me2PCH2PMe2.1450... 

Sulfur, thiolates and sulfide ligands form very stable complexes with platinum. Many complexes have platinum in the divalent state, but complexes with a Pt—S bond are formed with platinum in the zerovalent or tetravalent state. Several recent reviews have been written on various aspects of the platinum coordination chemistry of sulfur heteroatom ligands, and these are listed in Table 9. 

Since these substitution reactions follow a two-term rate law, it is clear that solvent effects are very significant. Poorly coordinating solvents are benzene, carbon tetrachloride and sterically hindered alcohols and strongly coordinating solvents are water, lower alcohols, DMF, DMSO, acetonitrile and nitromethane. The first-order rate constants are greater in DMSO than in water. Since the majority of precursor platinum complexes used in synthetic and mechanistic studies are halo complexes, the replacement of halide ligands by solvent and the reversibility of this reaction are important features of platinum halide chemistry. 

Pinacolone, o-(diphenylphosphino)benzoyl-coordination chemistry, 401 Piperidine, IV-hydroxy-metal complexes, 797 pA a values azole ligands, 77 Plant roots amino acids, 962 carboxylic acids, 962 Plastocyanin copper binding site, 557 copper(II) complexes, 772 copper(II) site in, 770 Platinum, dichlorobis(benzonitrile)-IR spectrum, 264 Platinum, cis-dichlorodianunine-antitumor activity, 34, 979 Platinum, ethylenebis(triphenylphosphine)-reactions with 5,6-dimethyl-2,l,3-benzothiadiazole, 194 Platinum blue formation, 265 Platinum complexes acetylacetone reactions, 380 amides, 491 amidines... 

Complexes of cyclic perfluoroolefins are also quite common. For example, the iron and platinum complexes of perfluorocyclobutene, 20 (62) and 21 (56), have been prepared. Recently the chemistry of the smallest cyclic perfluoro-olefin, perfluorocyclopropene, has been explored, and initial results indicate... 

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. 

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