512-56-1

A pale straw colored liquid. Inhalation may irritate or seriously burn respiratory tract. vapor or liquid may irritate or severely burn skin or eyes. Ingestion may irritate or burn the mucous membranes of the gastrointestinal tract.

TRIMETHYL PHOSPHATE may explode when heated. Residue from a large scale atmospheric pressure distillation of this chemical has exploded violently. METHYL ACID PHOSPHATE(512-56-1) is incompatible with nitrates. . Organophosphates are susceptible to formation of highly toxic and flammable phosphine gas in the presence of strong reducing agents such as hydrides. Partial oxidation by oxidizing agents may result in the release of toxic phosphorus oxides.

Water soluble.

This chemical is nonflammable.

Trimethyl phosphate (TMP), the simplest trialkyl ester of phosphoric acid, It is a colourless, nonvolatile liquid. soluble in most organic solvents, low solubility in water. TMP is stable in neutral, acidic or alkaline solutions, and is classified as "not readily biodegradable". Direct photodegradation is not expected because trimethyl phosphate does not absorb UV light.

ChEBI: A trialkyl phosphate that is the trimethyl ester of phosphoric acid.

Prepared by the reaction of phosphorus oxychloride with methanol.

The Journal of Organic Chemistry, 39, p. 3178, 1974 DOI: 10.1021/jo00935a041
Tetrahedron Letters, 28, p. 2981, 1987 DOI: 10.1016/S0040-4039(00)96262-2

Toxic by ingestion and inhalation, strong irritant to skin and eyes.

There are no reports on the toxicity of trimethyl phosphate to humans.

TMP is a mutagen, teratogen, and a cancercausing compound. The health hazard from this compound is somewhat different from those of the higher members of the organic phosphate series. While carcinogenicity is observed only for this phosphate, with mutagenicity and the teratogenic effects being more marked, higher alkyl phosphates are more neurotoxic but noncarcinogenic.
TMP is toxic at high dosages.LD50 value,oral(mice):1470 mg/kg(NIOSH 1986)
Laboratory tests on animals indicated clear evidence of its cancer-causing actions, producing uterine and skin tumors. There is so far no report on such carcinogenic actions in humans. The compound tested positive in mutagenic tests and caused fetal deaths and birth defects in mice, rats, and hamsters when given orally or intraperitoneally..

Notclassified

1 Gasoline additive at 0.25 g/gal for controlling surface ignition and spark plug fouling.
2 Methylating agent, chemical intermediate in the production of polymethyl polyphosphates.
3 Flame retardant solvent for paints and polymers.
4 Catalyst in the preparation of polymers and resins.

A system utilizing isolated anterior forearm stratum corneum conjunctum of man to study skin penetrating capacity of a series of organic phosphates was developed. Trimethyl phosphate was tested in the system and had the greatest skin-penetrating capacity of the 8 related compounds tested (Marzulli et al 1965).
Rats treated orally at 100 mg/kg and mice treated i.p. at 1000 mg/kg with [³²]P-labeled trimethyl phosphate excreted primarily dimethyl phosphate in the urine. Only traces of the parent compound were detected, and only in the rats at less than 6 h after treatment. S-Methyl cysteine and S-methyl cysteine N-acetate were also isolated. Small amounts of S-methyl glutathione were detected, presumably the initial methylation product in this series of metabolites (Jones 1970). Metabolism of trimethyl phosphate was faster in the mouse than in the rat, but there was no evidence of further conversion to monomethyl phosphate or inorganic phosphate in either species (Jackson and Jones 1968).

Purify the phosphate by fractionation through an efficient column at high reflux ratio. It is quite soluble in H2O; the solubility is 1:1 at 25o. [Becker J Am Chem Soc 74 2923 1952, IR: Bergmann et al. J Chem Soc 847 1952, McIvor et al. Can J Chem 36 820 1958, Kosolapoff Organophosphorus Compounds, Wiley p 258 1950, and Cherbuliez in Organo Phosphorus Compounds (Kosolapoff & Maier eds) Wiley Vol 6 pp 211-577 1973, Beilstein 1 IV 1259.]

TMP is mixed with a combustible solvent and destroyed by burning in a chemical incinerator.