Trimethyl phosphate
| Names | |
|---|---|
| IUPAC name
Trimethyl phosphate
| |
| Other names
Methyl phosphate
Phosphoric acid trimethyl ester TMP Trimethoxyphosphine oxide Trimethyl orthophosphate | |
| Properties | |
| C3H9PO4 (CH3O)3PO | |
| Molar mass | 140.07 g/mol |
| Appearance | Colorless liquid |
| Odor | Mild, pleasant |
| 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) |
| Miscible | |
| Solubility | Soluble in alcohols, diethyl ether, gasoline, toluene |
| Vapor pressure | 0.85 mmHg at 25 °C |
| Hazards | |
| 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) |
| Related compounds | |
| Related compounds
|
Phosphoric acid |
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
| Infobox references | |
Trimethyl phosphate ((CH3O)3PO) is the trimethyl ester of phosphoric acid.
Contents
Properties
Chemical
Trimethyl phosphate is a mild methylating agent, useful for dimethylation of anilines and related heterocyclic compounds.
Physical
Trimethyl phosphate is a viscous colorless or slightly yellow liquid. It is soluble in water and many organic solvents.
Availability
Trimethyl phosphate is sold by chemical suppliers.
Preparation
Trimethyl phosphate is prepared by treating phosphoryl chloride with methanol in the presence of an amine base
- POCl3 + 3 CH3OH + 3 R3N → (OCH3)3PO + 3 R3NH+Cl−
Projects
- Solvent for aromatic halogenations and nitrations
- Color inhibitor for fibers
Handling
Safety
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.
Storage
Trimethyl phosphate is best kept in closed plastic or glass bottles.
Disposal
Adding sodium hydroxide to the compound will hydrolyze it to sodium phosphates and methanol, both which can be diluted and poured down the drain.
