Trimethyl phosphite

Trimethyl phosphite is an organophosphorus compound with the formula P(OCH3)3, often abbreviated P(OMe)3. This colorless liquid is used as a ligand in organometallic chemistry and as a reagent in organic synthesis. The material also has a highly pungent smell. The molecule features a pyramidal phosphorus(III) center bound to three methoxy groups. Trimethyl phosphite is an organophosphorus compound with the formula P(OCH3)3, often abbreviated P(OMe)3. This colorless liquid is used as a ligand in organometallic chemistry and as a reagent in organic synthesis. The material also has a highly pungent smell. The molecule features a pyramidal phosphorus(III) center bound to three methoxy groups. Trimethyl phosphite is prepared from phosphorus trichloride: It is susceptible to oxidation to trimethyl phosphate. It reacts with a catalytic amount of methyl iodide in the Arbuzov reaction to give dimethyl methylphosphonate: As a ligand, trimethyl phosphite has a smaller cone angle and better acceptor properties relative to trimethylphosphine. A representative derivative is the colorless, tetrahedral complex Ni(P(OMe)3)4 (m.p. 108 °C). The tridentate ligand called the Klaui ligand is derived from trimethylphosphite. The formation of this ligand illustrates the susceptibility of trimethylphosphite (and metal complexes thereof) to the Arbuzov reaction. Trimethyl phosphite is also used as a mild desulfurization reagent in organic synthesis, for example in the preparation of derivatives of tetrathiafulvalene. The LD50 is 1600–2890 mg/kg (oral, rat).