1: water 2: NaNO3; AgNO3; KOH / acetone; water View Scheme

NaNO3; AgNO3; KOH in water; acetone byproducts: AgI; NaNO3 in water/acetone and AgNO3 in water was added to the Pt-comd., the suspn. stirred for 0.5 h, AgI filtered off, excess malonic acid neutralized with KOH added, pH of the soln. adjusted to 5; the product crystd. within 1 d, the crystals filtered, washed with ethanol/water, ethanol and Et2O, dried in vac. at room temp.; elem. anal.;