Potassium hexachloroplatinate, solubility

Most alkaloids are isolated from plant extracts by conversion into the difficultly soluble salts which they form with complex acids such as hexachloroplatinic acid, chlorauric add, phosphotungstic add, hydroferro-cyanic add, Rdnecke s add, etc. Perchloric add, picric add, flavianic add, mercuric chloride, iodine in potassium iodide are also used. 

None of the accepted preparative methods12 for disodium hexa-chloroplatinate(IV), Na2[PtCl6], is entirely suitable for routine use, because these procedures require reaction of a mixture of solid sodium chloride and platinum metal with chlorine gas at temperatures near 500°. However, a preparation of the desired compound is described below which yields a product of very high purity and which is much more convenient than those previously reported since only solution chemistry is involved. Unlike the corresponding ammonium and potassium salts, disodium hexachloroplatinate(IV) exhibits high solubility in water and in several nonaqueous solvents, including ethanol, methanol, and Ar,/V-dimethylformamide—a fact which enables one to extend the range of studies of the chemistry of hexachloroplatinate(IV). 

The sodium salt of the hexachloroplatinate(IV) ion, Na2PtCl6, was prepared in the same manner as the potassium salt, except that NaCl was added instead of KCl. Furthermore, due to solubility differences, the product was washed only with 95 % ethanol. 

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