Potassium tetrachloroplatinate(II) is the chemical compound

Chemical compound

A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...

 with the formula

Chemical formula

A chemical formula or molecular formula is a way of expressing information about the atoms that constitute a particular chemical compound....

 K₂PtCl₄. This reddish orange salt

Salt

In chemistry, salts are ionic compounds that result from the neutralization reaction of an acid and a base. They are composed of cations and anions so that the product is electrically neutral...

 is an important reagent

Reagent

A reagent is a "substance or compound that is added to a system in order to bring about a chemical reaction, or added to see if a reaction occurs." Although the terms reactant and reagent are often used interchangeably, a reactant is less specifically a "substance that is consumed in the course of...

 for the preparation of other coordination complexes

Complex (chemistry)

In chemistry, a coordination complex or metal complex, is an atom or ion , bonded to a surrounding array of molecules or anions, that are in turn known as ligands or complexing agents...

 of platinum

Platinum

Platinum is a chemical element with the chemical symbol Pt and an atomic number of 78. Its name is derived from the Spanish term platina del Pinto, which is literally translated into "little silver of the Pinto River." It is a dense, malleable, ductile, precious, gray-white transition metal...

. It consists of potassium

Potassium

Potassium is the chemical element with the symbol K and atomic number 19. Elemental potassium is a soft silvery-white alkali metal that oxidizes rapidly in air and is very reactive with water, generating sufficient heat to ignite the hydrogen emitted in the reaction.Potassium and sodium are...

 cations and the square planar

Square planar

The square planar molecular geometry in chemistry describes the stereochemistry that is adopted by certain chemical compounds...

 dianion PtCl₄^2-. Related salts are also known including K₂PtCl₄, which is brown-colored and soluble in alcohols, and quaternary ammonium salts

Quaternary ammonium cation

Quaternary ammonium cations, also known as quats, are positively charged polyatomic ions of the structure NR4+, R being an alkyl group or an aryl group. Unlike the ammonium ion and the primary, secondary, or tertiary ammonium cations, the quaternary ammonium cations are permanently charged,...

, which are soluble in a broader range of organic solvents.

Preparation

Potassium tetrachloroplatinate is prepared by reduction of the corresponding hexachloroplatinate salt

Potassium hexachloroplatinate

Potassium hexachloroplatinate, an inorganic compound, is an example of a comparatively insoluble potassium salt.The precipitation of this compound from solutions of hexachloroplatinic acid was formerly used for the determination of potassium by gravimetry....

 with hydrazine

Hydrazine

Hydrazine is an inorganic compound with the formula N2H4. It is a colourless flammable liquid with an ammonia-like odor. Hydrazine is highly toxic and dangerously unstable unless handled in solution. Approximately 260,000 tons are manufactured annually...

. K₂PtCl₄ is one of the salts that is most easily obtained from platinum ore

Ore

An ore is a type of rock that contains minerals with important elements including metals. The ores are extracted through mining; these are then refined to extract the valuable element....

s. The complex is appreciably soluble only in water. Treatment with alcohols, especially in the presence of base, causes reduction to platinum metal. Conversion to organic salts, such as [PPN]₂PtCl₄ are soluble in chlorocarbons.

Reactions

The chloride ligands on [PtCl₄]^2- are displaced by many other ligand

Ligand

In coordination chemistry, a ligand is an ion or molecule that binds to a central metal atom to form a coordination complex. The bonding between metal and ligand generally involves formal donation of one or more of the ligand's electron pairs. The nature of metal-ligand bonding can range from...

s to afford derivatives:

PtCl₄²⁻ + 2 PPh₃

Triphenylphosphine

Triphenylphosphine is a common organophosphorus compound with the formula P3 - often abbreviated to PPh3 or Ph3P. It is widely used in the synthesis of organic and organometallic compounds. PPh3 exists as relatively air stable, colorless crystals at room temperature...

  → cis-PtCl₂(PPh₃)₂ + 2 Cl⁻

The anti-cancer drug Cisplatin

Cisplatin

Cisplatin, cisplatinum, or cis-diamminedichloroplatinum is a chemotherapy drug. It is used to treat various types of cancers, including sarcomas, some carcinomas , lymphomas, and germ cell tumors...

 can similarly be prepared:

PtCl₄²⁻ + 2 NH₃

Ammonia

Ammonia is a compound of nitrogen and hydrogen with the formula . It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or...

  → cis-PtCl₂(NH₃)₂ + 2 Cl⁻

Enedithiolates displace all four chloride ligands to give bis(dithiolene

Dithiolene

Metal dithiolene complexes are complexes containing dithiolene ligands. Dithiolene ligands are unsaturated bidentate ligand wherein the two donor atoms are sulfur. Dithiolenes are often referred to as "metallodithiolenes" or "dithiolene complexes"...

) complexes. Reduction gives colloidal platinum of potential interest in for catalysis.

Historically, an important reaction involves ammonia and [PtCl₄]^2-. This reaction affords a deep green precipitate with the formula PtCl₂(NH₃)₂. This material, known as Magnus' green salt

Magnus' green salt

Magnus' green salt is the chemical compound with the formula [Pt4][PtCl4]. This species has been of interest in materials chemistry and solid-state physics because of its one-dimensional structure. It contains a linear chain of alternating [PtCl4]2− anions and [Pt4]2+ cations, in which the...

, is a semiconducting coordination polymer consisting of chains of alternating [PtCl₄]^2- and [Pt(NH₃)₄]²⁺ centres.