Monocarbonyl platinum dichloride

Monocarbonyl Platinum Dichloride, PtCl2. CO, obtained by heating the di- and sesqui-earbonyls to 250° C., yields golden yellow crystals, melting at 195° C. to an orange-red liquid. The crystals are hygroscopic and are decomposed by water, the main reaction consisting in the deposition of platinum and liberation of carbon dioxide and hydrochloric acid thus 3 ... 

It is also prepared by evaporating a solution of monocarbonyl platinum dichloride in hydrochloric acid on the water-bath in a current of hydrogen bromide. Upon recrystallisation from benzene it yields orange-red crystals, entirely free from platinum and platinous bromide. 

Carbonyl platinum dichloride has a distinctly basic character. It dissolves in excess of hydrochloric acid to a lemon-yellow solution, due, perhaps, to the formation of a soluble hydrochloride, PtCl2.CO.HCl. This solution is a powerful reducing agent, effecting the reduction of silver, gdld, and mercury from their salts.1 The monocarbonyl unites with soluble metallic chlorides, such as those of the alkali metals, to yield yellow, crystalline double salts. These, however, are so readily soluble and so easily decomposed that their satisfactory isolation has proved difficult. With the chlorides of certain organic bases, however, well-defined compounds have been obtained.4... 

Dicarbonyl Platinum Dichloride, PtCI2.2CO, is obtained by heating the monocarbonyl to 150° C. in a current of carbon monoxide. Upon sublimation in the gas it yields colourless needles melting at 142° C. to a yellow liquid. If raised to the melting-point in air, carbon monoxide is evolved. The residue solidifies and melts again at 190° C. A little above this temperature further decomposition sets in. 

Monocarbonyl Platinum Di-iodide, Ptl2. CO, is obtained3 by adding dilute hydriodic acid to a solution of the carbonyl platinum dichloride in hydrochloric acid ... 

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