Potassium amminetrichloroplatinate(II)
CAS 13820-91-2
Known classically as Cossa's salt, K[Pt(NH₃)Cl₃] is the key mono-ammine platinum(II) intermediate — the compound through which controlled, stepwise ligand substitution on a square-planar platinum centre is achieved, and the standard entry point to mixed-ligand platinum complexes.
Typical specification
| Molecular formula | K[Pt(NH₃)Cl₃] |
|---|---|
| Molecular weight | 357.57 |
| Purity (trace metals basis) | ≥ 99% |
| Platinum content | ≥ 54.5% (typical 54.52%) |
| Appearance | Orange-yellow to pale beige crystalline powder |
| Total impurities | ≤ 0.05% |
| Other PGMs (Pd, Rh, Ir, Ru, Au, Ag) | ≤ 0.02% each |
| Base metals (Cu, Fe, Ni, Al, Pb, Mn, Cr, Mg, Sn, Si, Zn, Bi) | ≤ 0.005% each; Pb ≤ 0.003% |
| Test methods | GB/T 37653-2019, YS/T 646-2007 |
| HS code (export) | 2843900039 |
Lot-specific COA issued with every shipment. SDS and ICP elemental impurity data available on request.
Where K[Pt(NH₃)Cl₃] is used
Stepwise platinum complex synthesis
With one ammine already installed and three labile chlorides remaining, Cossa's salt allows controlled sequential substitution — the practical route to cis- and trans-configured mixed-ligand Pt(II) complexes that cannot be built cleanly from K₂PtCl₄ in one step.
Pharmaceutical intermediate synthesis
A recognised intermediate in the manufacture of platinum coordination compounds for the pharmaceutical sector, where controlled geometry and low trace-metal carryover determine downstream specification compliance.
Coordination chemistry and materials research
Used in fundamental studies of trans effect and substitution kinetics on square-planar platinum, and as a precursor to luminescent and catalytic platinum complexes in materials research.
Storage and shipping
Storage. Store sealed, cool and dry, protected from light. Stable in air under normal handling.
Shipping. Ships in sealed glass or fluorinated bottles with SDS by commercial courier.
Packaging. 1 g · 5 g · 25 g · 100 g · Custom lots by contained-metal weight
Synonyms
- Cossa's salt
- Potassium trichloroammineplatinate(II)
- K[Pt(NH3)Cl3]
- Potassium amminetrichloroplatinate
- Ammine trichloro platinate potassium
Frequently asked questions
Why start from Cossa's salt instead of K₂PtCl₄?
K₂PtCl₄ carries four identical chlorides, so introducing a single ammine cleanly requires careful stoichiometric control and gives mixtures. Cossa's salt arrives with that first substitution already done and isolated, which shortens the route and improves isomeric control in mixed-ligand syntheses.
What analytical documentation ships with each lot?
A certificate of analysis stating assayed platinum content and a full impurity panel — other platinum-group metals and twelve base metals reported individually — tested against GB/T 37653-2019 and YS/T 646-2007. ICP-MS panels to customer specification are available for pharmaceutical use.
How is pricing structured?
On contained platinum (~54.5%) at the day's Pt fixing plus a stated conversion charge, so the metal and the chemistry can be benchmarked separately. Recurring volumes can be fixed forward against your production schedule.
Do you take back platinum residues?
Yes — mother liquors, filter residues and off-spec material are assayed on receipt and the recovered platinum credited against your next order.