| IUPAC name
| Other names
Phosphoric acid trimethyl ester
|Molar mass||140.07 g/mol|
|Density|| 1.2144 g/cm3 (20 °C)|
1.197 g/cm3 (25 °C)
|Melting point||−46 °C (−51 °F; 227 K)|
|Boiling point||197 °C (387 °F; 470 K)|
|Solubility||Soluble in alcohols, diethyl ether, gasoline, toluene|
|Vapor pressure||0.85 mmHg at 25 °C|
|Safety data sheet||Sigma-Aldrich|
|Flash point||150 °C (302 °F; 323 K)|
|Lethal dose or concentration (LD, LC):|
LD50 (Median dose)
|840 mg/kg (rat, oral)|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Trimethyl phosphate ((CH3O)3PO) is the trimethyl ester of phosphoric acid.
Trimethyl phosphate is a mild methylating agent, useful for dimethylation of anilines and related heterocyclic compounds.
Trimethyl phosphate is a viscous colorless or slightly yellow liquid. It is soluble in water and many organic solvents.
Trimethyl phosphate is sold by chemical suppliers.
- POCl3 + 3 CH3OH + 3 R3N → (OCH3)3PO + 3 R3NH+Cl−
- Solvent for aromatic halogenations and nitrations
- Color inhibitor for fibers
Trimethyl phosphate is irritant, though it does not show high toxicity. Hydrolysis will generate methanol which is toxic. Being non-volatile, its vapors do not accumulate in any significant amount in a closed environment at standard conditions, and thus it does not pose a significant fire or explosion hazard.
Trimethyl phosphate is best kept in closed plastic or glass bottles.