Platinum metal derivatives

For selective saturation of one of several double bonds, palladium or Raney nickel can be used. Platinum is less selective but can nevertheless sometimes be used. The reaction is interrupted after consumption of the calculated amount of hydrogen. Sulfur must be completely absent during hydrogenation of aromatic rings with platinum metals derivatives of benzene such as benzoic acid and phenol, also naphthalene, are more easily hydrogenated than benzene itself but for such cases it is often advantageous to use nickel catalysts in an autoclave. 

The influence of cobalt(III)—amine cations on native and denatured calf thymus DNA was first reported in 1972—3 [87, 88]. Subsequent studies on tRNA [89] and DNA [90] confirmed that such complex cations are very effective in stabilizing secondary and tertiary structures of nucleic acids. Karpel et al have extended the studies on cobalt to a series of platinum metal derivatives and the results are summarized in Table l.III 91]. 

Chemistry and structure of semi-sandwich platinum metal metallacarboranes derived from nido-Ci39Hi2 97JOM(536/537)51. 

Rapoport s findings have been confirmed in the authors laboratory where the actions of carbon-supported catalysts (5% metal) derived from ruthenium, rhodium, palladium, osmium, iridium, and platinum, on pyridine, have been examined. At atmospheric pressure, at the boiling point of pyridine, and at a pyridine-to-catalyst ratio of 8 1, only palladium was active in bringing about the formation of 2,2 -bipyridine. It w as also found that different preparations of palladium-on-carbon varied widely in efficiency (yield 0.05-0.39 gm of 2,2 -bipyridine per gram of catalyst), but the factors responsible for this variation are not knowm. Palladium-on-alumina was found to be inferior to the carbon-supported preparations and gave only traces of bipyridine,... 

Advances in platinum metal carbonyls and their substituted derivatives, I. Ruthenium and osmium carbonyls. S. C. Tripathi, S. C. Srivastava, R. P. Mani and A. K. Shrimal, Inorg. Chim. Acta, 1975, 15,249-290 (327). 

Selective catal3ftic oxidation with air of glycerol and oxygenated derivatives on platinum metals... 

Mossbauer spectroscopy with started only in 1965, when Harris et al. [322] measured the Mossbauer absorption spectra of the 99 keV transition of Pt in platinum metal as a function of temperature (between 20 and 100 K) and of absorber thickness and derived the temperature dependence of the Debye-Waller factor. 

The rearrangement of platinacyclobutanes to alkene complexes or ylide complexes is shown to involve an initial 1,3-hydride shift (a-elimina-tion), which may be preceded by skeletal isomerization. This isomerization can be used as a model for the bond shift mechanism of isomerization of alkanes by platinum metal, while the a-elimination also suggests a possible new mechanism for alkene polymerisation. New platinacyclobutanes with -CH2 0SC>2Me substituents undergo solvolysis with ring expansion to platinacyclopentane derivatives, the first examples of metallacyclobutane to metallacyclopentane ring expansion. The mechanism, which may also involve preliminary skeletal isomerization, has been elucidated by use of isotopic labelling and kinetic studies. 

Platinum - the atomic number is 78 and the chemical symbol is Pt. The name derives from the Spanish platina for silver . In 1735, the Spanish mathematician Don Antonio de Ulloa found platinum in Peru, South America. In 1741, the English metallurgist Charles Wood foimd platinum from Columbia, South America. In 1750, the English physician William Brownrigg prepared purified platinum metal. 

This class of compounds showing explosive instability deals with heavy metals bonded to elements other than nitrogen and contains the separately treated groups GOLD COMPOUNDS LEAD SALTS OF NITRO COMPOUNDS LITHIUM PERALKYLURANATES MERCURY COMPOUNDS METAL ACETYLIDES METAL FULMINATES METAL OXALATES PLATINUM COMPOUNDS PRECIOUS METAL DERIVATIVES SILVER COMPOUNDS... 

Ruthenium is derived from platinum metal ores. Method of production depends on the type of ore. However, the extraction processes are simdar to those of other nohle metals (see Platinum, Rhodium and Iridium). Ruthenium, like Rhodium, may he obtained from accumulated anode sludges in electrolytic refining of nickel or copper from certain types of ores. Also, residues from refining nickel by Mond carbonyl process contain ruthenium and other precious metals at very low concentrations. The extraction processes are very lengthy, involving smelting with suitable fluxes and acid treatments. 

Several studies on models have been reported, both on the binding of a range of metals to apometallothionein and the design of ligands, particularly with Cys-X-Cys and Cys-X-Y-Cys arrangements as found for metallothionein.1163,1164 All metal derivatives appear to bind in metal-thiolate clusters.1149 Platinum has also been found bound to metallothionein in rat tissues following treatment with cisplatin and the trans isomer.1165... 

As many other derivatives of the platinum metals the alkoxide ones find... 

As for palladium discussed above, the majority of platinacyclopentanes are based on the divalent metal. However, the structurally characterised complex [Pt(C4H8) (Ph)I(bipy)] 91 has been obtained by treating [Pt(C4H8)(bipy)] 85 with di-phenyliodonium triflate followed by triflate-iodide metathesis [Eq. (36)]. As in the palladium example 79 described above, both cis and trans oxidative addition products are observed.103 Prior to this, the structurally characterised platinum(IV) derivative [Pt(C4H8)I2(PMe2Ph)2] 92 had been obtained via trans oxidative addition of iodine to [Pt(C4H8)(PMe2Ph)2] [Eq. (37)].113... 

It explodes fairly violently above 250°C, as does the pyridine analogue. See other N-METAL DERIVATIVES, PLATINUM COMPOUNDS... 

Plant cleaning incidents, 330 Platinum compounds, 330 Platinum group metals, 331 Poly(aminium) perchlorates, 331 Polyazacaged metal perchlorates, 332 Polycondensation reaction incidents, 332 Poly(dimercuryimmonium) compounds, 332 Poly(dimethylsilyl)chromate, 333 Polymeric peroxyacids, 333 Polymerisation incidents, 333 Polynitroalkyl compounds, 336 Polynitroaryl compounds, 337 Polynitroazopyridines, 340 Polyperoxides, 341 Polypropylene powder, 342 Precious metal derivatives, 342 Preparative hazards, 342... 

Molybdenum trioxide, intercalation into, 12, 823 Molybdocenes, as anticancer agents, 1, 892 MOMNs, see Metal-organometallic coordination networks Monisocyanides, with silver(I) complexes, 2, 223 Monitoring methods, kinetic studies, 1, 513 Mono(acetylacetonate) complexes, with Ru and Os halfsandwich rf-arenes, 6, 523 tj2-Monoalkene monodentate ligands, with platinum divalent derivatives, 8, 617 tetravalent derivatives, 8, 625 theoretical studies, 8, 625 zerovalent derivatives, 8, 612... 

Activation of the triple bond of enynes with electrophilic metal derivatives, especially cationic gold complexes, platinum salts such as PtCl2, and ruthenium derivatives, has been reviewed.117 These catalysts make possible nucleophilic addition of the double... 

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