Tetrakis(triphenylphosphine)platinum(0)

Tetrakis(triphenylphosphine)platinum(0) is the chemical compound with the formula Pt(P(C₆H₅)₃)₄, often abbreviated Pt(PPh₃)₄. The bright yellow compound is used as a precursor to other platinum complexes.

Tetrakis(triphenylphosphine)­platinum(0)

Names
IUPAC name Tetrakis(triphenylphosphane)platinum(0)
Other names Tetrakis(triphenylphosphane)platinum(0) TPP platinum(0)
Identifiers
CAS Number	14221-02-4 Y
3D model (JSmol)	Interactive image
ChemSpider	10152943
ECHA InfoCard	100.034.610
EC Number	238-087-4
PubChem CID	11979705
CompTox Dashboard (EPA)	DTXSID4065733
InChI InChI=1S/4C18H15P.Pt/c4*1-4-10-16(11-5-1)19(17-12-6-2-7-13-17)18-14-8-3-9-15-18;/h4*1-15H; Key: SYKXNRFLNZUGAJ-UHFFFAOYSA-N
SMILES c0ccccc0[P+](c0ccccc0)(c0ccccc0)[Pt-4]([P+](c0ccccc0)(c0ccccc0)c0ccccc0)([P+](c0ccccc0)(c0ccccc0)c0ccccc0)[P+](c0ccccc0)(c0ccccc0)c0ccccc0
Properties
Chemical formula	C72H60P4Pt
Molar mass	1244.251 g·mol−1
Appearance	yellow crystals
Melting point	160 °C (320 °F; 433 K)
Solubility in water	Insoluble
Structure
Coordination geometry	four triphenylphosphine unidentate ligands attached to a central Pt(0) atom in a tetrahedral geometry
Molecular shape	tetrahedral
Dipole moment	0 D
Hazards
Occupational safety and health (OHS/OSH):
Main hazards	PPh3 is an irritant
GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H302
NFPA 704 (fire diamond)	2 1
Safety data sheet (SDS)	External MSDS
Related compounds
Related complexes	Tetrakis(triphenylphosphine)palladium(0) tetrakis(triphenylphosphine)nickel(0) tris(triphenylphosphine)platinum(0)
Related compounds	triphenylphosphine
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

Structure and behavior

The molecule is tetrahedral, with point group symmetry of T_d, as expected for a four-coordinate metal complex of a metal with the d¹⁰ configuration. Even though this complex follows the 18 electron rule, it dissociates triphenylphosphine in solution to give the 16e⁻ derivative containing only three PPh₃ ligands:

Pt(PPh₃)₄ → Pt(PPh₃)₃ + PPh₃

Synthesis and reactions

The complex is typically prepared in one-pot reaction from potassium tetrachloroplatinate(II). Reduction of this platinum(II) species with alkaline ethanol in the presence of excess triphenylphosphine affords the product as a precipitate. The reaction occurs in two distinct steps. In the first step, PtCl₂(PPh₃)₂ is generated. In the second step, this platinum(II) complex is reduced. The overall synthesis can be summarized as:

K₂[PtCl₄] + 2KOH + 4PPh₃ + C₂H₅OH → Pt(PPh₃)₄ + 4KCl + CH₃CHO + 2H₂O

Pt(PPh₃)₄ reacts with oxidants to give platinum(II) derivatives:

Pt(PPh₃)₄ + Cl₂ → cis-PtCl₂(PPh₃)₂ + 2 PPh₃

Mineral acids give the corresponding hydride complexes:

Pt(PPh₃)₄ + HCl → trans-PtCl(H)(PPh₃)₂ + 2 PPh₃

The reaction with oxygen affords a dioxygen complex:

Pt(PPh₃)₄ + O₂ → Pt(η²-O₂)(PPh₃)₂ + 2 PPh₃

This complex is a precursor to the ethylene complex

Pt(η²-O₂)(PPh₃)₂ + C₂H₄ → Pt(η²-C₂H₄)(PPh₃)₂ + "NaBH₂(OH)₂"