|Molar mass||1244.24 g/mol|
|Melting point||160 °C (320 °F; 433 K)|
|four triphenylphosphine unidentate
ligands attached to a central Pt(0)
atom in a tetrahedral geometry
|Main hazards||PPh3 is an irritant|
|Safety data sheet||External MSDS|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|what is ?)(|
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.
Structure and behavior
The molecule is tetrahedral, with point group symmetry of Td, 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"
- Ugo, R.; Cariati, F.; La Monica, G. (1968). "Tris- and tetrakis(triphenylphosphine)platinum(0)". Inorganic Syntheses. 11: 115–108. doi:10.1002/9780470132593.ch32.
- Safety Data Sheet http://www.alfa.com/content/msds/english/10549.pdf
- Miessler, Gary L., and Donald A. Tarr. Inorganic Chemistry. 3rd ed. Upper Saddle River, NJ: Pearson Prentice Hall, 2004.