Diphosphorus tetrachloride

Diphosphorus tetrachloride is an inorganic compound with a chemical formula P₂Cl₄. It is a colorless liquid that decomposes near room temperature and ignites in air.^[1]

Diphosphorus tetrachloride

Identifiers
CAS Number	13497-91-1 Y
3D model (JSmol)	Interactive image
ChemSpider	123003
PubChem CID	139480
CompTox Dashboard (EPA)	DTXSID10159174
InChI InChI=1S/Cl4P2/c1-5(2)6(3)4 Key: SWRNIYAQKATHDJ-UHFFFAOYSA-N
SMILES P(P(Cl)Cl)(Cl)Cl
Properties
Chemical formula	P2Cl4
Appearance	colorless liquid
Melting point	−28 °C; −19 °F; 245 K
Boiling point	180 °C; 356 °F; 453 K
Related compounds
Other anions	Diphosphorus tetrafluoride Diphosphorus tetraiodide
Related compounds	Diphosphorus tetrafluoride Diphosphorus tetraiodide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Production

It was first prepared in 1910 by Gauthier by the following reaction:

2 PCl₃ + H₂ → P₂Cl₄ + 2 HCl

An improved method involves coevaporation of phosphorus trichloride and copper, as described by the following:^[1]

2 PCl₃ + 2 Cu → P₂Cl₄ + 2 CuCl

Reactions

Near room temperature, the compound degrades to give phosphorus trichloride and an ill-defined phosphorus monochloride:

P₂Cl₄ → PCl₃ + 1/n [PCl]n

The compound adds to cyclohexene to give trans-C₆H₁₀-1,2-(PCl₂)₂.^[1]