Triphenyl phosphite is the organophosphorus compound with the formula P(OC6H5)3.

Triphenylphosphite is prepared from phosphorus trichloride and phenol in the presence of a catalytic amount of base: Triphenylphosphite is a precursor to trimethylphosphine, it serves as a source of P3+ that is less electrophilic than phosphorus trichloride:[1] Triphenylphosphite is quaternized by methyl iodide:[2] Triphenylphosphite is a common ligand in coordination chemistry.

It forms zero-valent complexes of the type M[P(OC6H5)3]4 (M = Ni, Pd, Pt).

The nickel complex can be prepared by displacement of the diene from bis(cyclooctadiene)nickel:[3] Related complexes are homogeneous catalysts for the hydrocyanation of alkenes.

[4] Triphenylphosphite is a notable example of polyamorphism in organic compounds, namely it exists in two different amorphous forms at temperatures about 200 K.[5] One polymorphic modification of triphenyl phosphite was obtained by means of crystallization in ionic liquids.