my-server
← Wiki

Tetraphenyldiphosphine

Tetraphenyldiphosphine is the organophosphorus compound with the formula [PPh<sub>2</sub>]<sub>2</sub>, where Ph = phenyl (C<sub>6</sub>H<sub>5</sub>). 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...

2 Ph<sub>2</sub>PCl + 2 Na → Ph<sub>2</sub>P-PPh<sub>2</sub> + 2 NaCl

...or dehydrogenation of diphenylphosphine catalyzed by bis(triphenylphospine)nickel(II) bromide:

2&nbsp;Ph<sub>2</sub>PH&nbsp;→ Ph<sub>2</sub>P-PPh<sub>2</sub>&nbsp;+ H<sub>2</sub>

The compound is used as a source of the Ph<sub>2</sub>P<sup>−</sup> group.

Ph<sub>2</sub>P-PPh<sub>2</sub> + 2 Na → + 2 NaPPh<sub>2</sub>

Alternatively, the compound can homolyze along the weak P&ndash;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.

References