(C₂H₅O)₂HPO A colorless liquid with a boiling point of 138°C; soluble in water and common organic solvents; used as a paint solvent, antioxidant, and reducing agent.

It has chemical formula C₂₂H₃₁O₃P.

Triethylphosphite is an organophosphorus compound with the formula P(OCH₂CH₃)₃, often abbreviated P(OEt)₃ This colorless liquid is used as a ligand in organometallic chemistry and as a reagent in organic synthesis. The molecule features a pyramidal phosphorus(III) center bound to three ethoxide groups.

Triphenyl phosphite is the chemical compound with the formula P(OC₆H₅)₃. This colourless viscous liquid is the ester of phosphorous acid and phenol. It is used as a ligand in organometallic chemistry. Nickel complexes of this ligand are homogeneous catalysts for the hydrocyanation of alkenes.