Tetraphenyldiphosphine
Tetraphenyldiphosphine is the organophosphorus compound with the formula 2, where Ph = phenyl. 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.
Tetraphenyldiphosphine is produced by reductive coupling of chlorodiphenylphosphine...
...or dehydrogenation of diphenylphosphine catalyzed by bis(triphenylphospine)nickel(II) bromide:
The compound is used as a source of the Ph2P− group.
Alternatively, the compound can homolyze along the weak P-P bond, in which case the resulting radicals add to alkenes and alkynes.
Oxidation with oxygen or sulfur gives the corresponding diphosphine dioxide or disulfide.