Diphenylphosphide

Diphenylphosphide is an organophosphorus compound with the chemical formula (C6H5)2P-. It is the conjugate base of diphenylphosphine ((C6H5)2PH). Diphenylphosphide is typically encountered as its alkali metal salts, such as lithium diphenylphosphide (LiPPh2) or sodium diphenylphosphide (NaPPh2). These salts are commonly prepared by the reaction of diphenylphosphine with an alkali metal hydride or organolithium reagent.

The diphenylphosphide anion is a strong nucleophile and a strong base. Its nucleophilicity makes it useful in organic synthesis for the formation of carbon-phosphorus bonds. It readily reacts with electrophiles such as alkyl halides, acyl halides, and epoxides. This reactivity is exploited in the synthesis of various phosphine ligands and other organophosphorus compounds that find applications in catalysis and materials science.

Diphenylphosphide and its derivatives are air-sensitive and are usually handled under an inert atmosphere to prevent oxidation. The corresponding alkali metal phosphides are often commercially available as solutions in ethereal solvents like tetrahydrofuran. The study of diphenylphosphide and its reactions provides insight into the chemistry of phosphide anions and their role in phosphorus-containing molecules.