How is Sodium tetrachloroplatinate(2-) hydrate (2:1:1) (CAS: 207683-21-4) typically synthesized?

Sodium tetrachloroplatinate(2-) hydrate (2:1:1) is typically synthesized by the reaction of sodium chloride and platinum(II) chloride in a stoichiometric ratio. The process involves the formation of a precipitate which is then filtered, washed, and dried under vacuum. This compound can also be prepared by the hydrolysis of platinum tetrachloride in the presence of a base, followed by the addition of sodium chloride.