Dimethylphosphite
Dimethylphosphite.png
Names
Preferred IUPAC name
Dimethyl phosphonate
Other names
Phosphonic acid, dimethyl ester
Identifiers
3D model (JSmol)
ChEMBL
ChemSpider
ECHA InfoCard 100.011.622 Edit this at Wikidata
UNII
  • InChI=1S/C2H7O3P/c1-4-6(3)5-2/h3H,1-2H3
    Key: DLQDGVZAEYZNTG-UHFFFAOYSA-N
  • COP(O)OC
Properties
C2H7O3P
Molar mass 110.049 g·mol−1
Appearance colorless liquid
Density 1.20 g/cm3
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Dimethyl hydrogen phosphite (DMHP), also known as Dimethylphosphite, is an organophosphorus compound with the formula (CH3O)2P(O)H. 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]

Due to the presence of hydrogen, a "soft" ligand, the compound resonates. DMHP exists in chemical equilibrium, in two structures. One of the structures has a lone electron cloud, which is nucleophilically attacking the remaining tetrahedral structure. Due to the structural equilibrium tending towards the phosphonate, this reaction is slow, needing a chemical or electromagnetic catalyst (heat).

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.[2] 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.[3]

References[edit]

  1. ^ Balint, Erika; Tajti, Adam; Drahos, Laszlo; Ilia, Gheorge; Keglevich, Gyorgy (2013). "Alcoholysis of Dialkyl Phosphites Under Microwave Conditions". Current Organic Chemistry. 17 (5): 555–562. doi:10.2174/1385272811317050010.{{cite journal}}: CS1 maint: uses authors parameter (link)
  2. ^ Sipri - Chemical Weapons: Destruction and Conversion. p 57-62
  3. ^ Mark A. Prelas, Dabir S. Viswanath,. Science and Technology of Terrorism and Counterterrorism, Second lllllEdition. p 341-342.