Tetraphenyldiphosphine

Tetraphenyldiphosphine is the organophosphorus compound with the formula [PPh₂]₂, where Ph = phenyl (C₆H₅). It is a white, air-sensitive solid that dissolves in nonpolar solvents. It is a centrosymmetric molecule with a P-P bond of 2.2592 Å.^[1]

Tetraphenyldiphosphine

Names
Preferred IUPAC name Tetraphenyldiphosphane
Identifiers
CAS Number	1101-41-3
3D model (JSmol)	Interactive image
ChEMBL	ChEMBL68039
ChemSpider	63839
EC Number	214-155-9
PubChem CID	70673
CompTox Dashboard (EPA)	DTXSID60149141
InChI InChI=1S/C24H20P2/c1-5-13-21(14-6-1)25(22-15-7-2-8-16-22)26(23-17-9-3-10-18-23)24-19-11-4-12-20-24/h1-20H Key: DAPZRBJQPPDZGH-UHFFFAOYSA-N
SMILES C1=CC=C(C=C1)P(C2=CC=CC=C2)P(C3=CC=CC=C3)C4=CC=CC=C4
Properties
Chemical formula	C24H20P2
Molar mass	370.372 g·mol−1
Appearance	white solid
Density	1.292 g/cm3
Melting point	125 °C (257 °F; 398 K)
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H250
Precautionary statements	P210, P222, P280, P302+P334, P370+P378, P422
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Tetraphenyldiphosphine is produced by reductive coupling of chlorodiphenylphosphine...^[2]

2 Ph₂PCl + 2 Na → Ph₂P-PPh₂ + 2 NaCl

...or dehydrogenation of diphenylphosphine catalyzed by bis(triphenylphospine)nickel(II) bromide:^[3]

2 Ph₂PH → Ph₂P-PPh₂ + H₂

The compound is used as a source of the Ph₂P⁻ group.^[4]

Ph₂P-PPh₂ + 2 Na → + 2 NaPPh₂

Alternatively, the compound can homolyze along the weak P–P bond, in which case the resulting radicals add to alkenes and alkynes.^[2]

Oxidation with oxygen or sulfur gives the corresponding diphosphine dioxide or disulfide.^[5]