A new synthesis of [195mPt]-tetraplatin has been described: By reaction of potassium hexachloroplatinate (195Pt) with trans-1,2-cyclohexanediamine in water.

Potassium tetrachloroplatinate (I) is treated with an equivalent amount of 1,2-diaminocyclohexane in degassed water under nitrogen. The precipitated complex (II) is filtered and washed with HCl, ethanol and diethyl ether. The precipitate is dissolved in N,N-dimethylformamide, filtered and reprecipitated by addition of methanol. The precipitate is collected and suspended in 0.5N HCl and treated with chlorine gas at 100 C to convert to the tetrachloroplatinum(IV) complex. Removal of excess chlorine and then solvent, dissolution in methanol, filtration and removal of the methanol by vacuum yields the yellow product (III) in about 83% yield.