Dimethylphosphite is an organophosphorus compound with the formula (CH3O)2P(O)H, known as dimethyl hydrogen phosphite (DMHP). Dimethylphosphite, is a minor tautomer of the phosphorus(V) derivative. It is a reagent for generating other organophosphorus compounds, exploiting the high reactivity of the P-H bond. The molecule is tetrahedral. It is a colorless liquid. The compounds can be prepared by methanolysis of phosphorus trichloride or by heating diethylphosphite in methanol.[1]
Although studies have not been reported for this compound, the closely related diethylphosphite exists predominantly as the phosphorus(V) tautomer.[2]
This tautomeric nature of DMHP made it desirable as a precursor to the G-series compounds, and it was the most successful among all other phosphonate precursors.[3] The now obsolete process, which used it as a precursor, was called the DMHP process, investigated by Otto Ambros' team and implemented to scale sarin production.[4]