Applications
Triphenylphosphine oxide is used as a catalyst, Lewis base, ligand for metals and starting material for the preparation of other phosphorus compounds. It is also used in epoxidations, Michael reactions and coupling reactions. It reacts with copper(II) halides and form coordination complexes of Copper(II). Further, it acts as a crystallization aid for chemical compounds. In addition to this, it is used for processing, extraction, separation and spectrophotometric determination of cadmium and mercury.

Solubility
Soluble in polar organic solvents. Slightly soluble in hexane and diethyl ether. Insoluble in water.

Notes
Incompatible with strong oxidizing agents.