Platinic compounds

Platin-oxyd, n. platinum oxide, specif, platinic oxide, platinum(IV) oxide. -oxydul, n. platinous oxide, platinum(II) oxide, -oxy-dulverbindung, /. platinous compoimd, platinum (II) compound, -oxydverbindung, /. platinic compound, specif, platinum (IV) compound. 

Only one series of diacido-diammino-palladous compounds is known, although, reasoning from analogy with the corresponding platinous compounds, a symmetrical series corresponding to the platos-ammines, NH3X yCI... 

Tetracido-diammino-platinic compounds, platini-ammines or... 

Tetrammino-platinous salts are known containing pyridine in place of ammonia. Thus, diammino-dipyridino-platinous salts have been prepared. These salts are interesting, as they exist in isomeric forms, and through them the configuration of the isomeric diacido-diammino-platinous compounds have been determined. It is well known that diacido-diammino-platinum exists in stereo-isomeric forms. These isomers react with two molecules of pyridine in such a manner that pyridine replaces acidic radicles in the complex with formation of diammino-dipyTidino-platinous salts. Depending upon which isomer is treated with pyridine, two different diammino-dipyridino-platinous salts are produced. Cis- or unsymmetrical dichloro-diammino-platinum is... 

These substances are obtained by heating the corresponding tetrani-mino-platinous salts. They dissolve in aqueous ammonia until reformation of the tetrammino-salts, and they can take up two atoms of chlorine yielding the corresponding platinic compound thus ... 

In the annnino-platinous compounds there is, as in the other amniino-metallic compounds, a complete transition series from tetrammino-platinous salt to tetra-acido-platinous salt for example, tetrammino-platinous chloride, [Pt(NH3)JC12, chloro-triammino-platinous chloride, [Pt(NH3)3Cl]Cl, dichloro-diammino-platinum, [Pt(NH3)2Cl2], trichloro-ammino-platinous salt, [Pt(NH3)Cl3]K, and potassium chloropiatinite, [PtCl6]K2, where all the ammonia is replaced by chlorine. Comparing the molecular conductivities, the first-mentioned compound has conductivity at 1000 litres dilution of 260, the next 115-8 in the third compound the conductivity drops almost to zero, the fourth has conductivity of 106-8, and the last salt has conductivity of 267.2... 

A series of compomids has been prepared containing a hydroxo-group in place of an acidic group in the pentaminino-platinic compounds. These have general formula [Pt(NH3)sOH]R3. 

With platinic compounds having a co-ordination number 6, the six co-ordinated units in the complex appear to adopt some symmetrical arrangement, and to behave as if they were located at the six vertices of an imaginary regular octahedron described about the sphere of influence of the central atom. Thus, the two isomers of [Pt(NH3)2Cl4] can be represented by ... 

Platinic compounds [see specific compounds under Platinum (IV)] Platinized asbestos, 1 160 3 129 Platinized silica gel, use of, in preparation of hydrogen bromide, 1 152... 

Platinous compounds [see specific compounds under Platinum (II)] Platinum (II) chloride, 5 208 6 209 analysis of, 5 209 Platinum (IV) chloride, 2 253 Platinum (II) complex compounds, anions, with 1,4-butadiene, K2[Cl3PtC4H6PtCI3], 6 216 anions, with ethylene, [Pt(C2H4)-CU]K, 5 211, 214... 

The acid may also be obtained electrolytically5 by passing an electric current through concentrated hydrochloric acid containing precipitated platinum in a fine state of subdivision, using platinum foil as electrodes. The anodic chlorine attacks the finely divided metal, yielding the tetrachloride, which dissolves in the liquid to form the acid. The finely divided metal is conveniently prepared for this purpose by precipitation with metallic zinc from a solution of a platinum salt. On concentrating the solution to obtain the pure chlor-platinic acid it is advisable to introduce a small quantity of chlorine to ensure the absence of platinous compounds. 

Toxicity is best prevented by dose reduction and decreased frequency of administration, which usually requires using the platin compounds... 

Carbonyl compounds are formed with platinous derivatives, as, for example, by passing carbon monoxide over platinous chloride at 250°. Under these conditions there is obtained a mixture of PtCl - 2 CO, and 2 PtClj 3 CO, which on further heating gives PtClj CO. Other platinous compounds yield similar derivatives. Carbonyl compounds may also be prepared by passing an equimolecular mixture of carbon monoxide and chlorine over platinum sponge or foil at 240°-250°. This reaction is sometimes used to detect the presence of small amounts of rhodium or certain base metals in platinum. ... 

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