Trimethyl phosphate
Names
Preferred IUPAC name
Other names
Phosphoric acid trimethyl
ester Methyl phosphate, tribasic
Trimethoxyphosphine oxide
Trimethyl orthophosphate fraction
Identifiers
Abbreviations
TMP
1071731
ChEBI
ChemSpider
ECHA InfoCard
100.007.405
49926
RTECS number
UNII
InChI=1S/C3H9O4P/c1-5-8(4,6-2)7-3/h1-3H3
Y Key: WVLBCYQITXONBZ-UHFFFAOYSA-N
Y InChI=1/C3H9O4P/c1-5-8(4,6-2)7-3/h1-3H3
Key: WVLBCYQITXONBZ-UHFFFAOYAV
Properties
(CH3 O)3 PO
Molar mass
140.08
Appearance
Colorless liquid
Melting point
−46 °C (−51 °F; 227 K)
Boiling point
197 °C (387 °F; 470 K)
good
Hazards
GHS labelling :
Danger
H302 , H315 , H318 , H319 , H340 , H350 , H351 , H361 , H373
P201 , P202 , P260 , P264 , P270 , P280 , P281 , P301+P312 , P302+P352 , P305+P351+P338 , P308+P313 , P310 , P314 , P321 , P330 , P332+P313 , P337+P313 , P362 , P405 , P501
NFPA 704 (fire diamond)
Except where otherwise noted, data are given for materials in their
standard state (at 25 °C [77 °F], 100 kPa).
Chemical compound
Trimethyl phosphate is the trimethyl ester of phosphoric acid . It is a colourless, nonvolatile liquid. It has some specialized uses in the production of other compounds.[ 1]
Production
Trimethyl phosphate is prepared by treating phosphorus oxychloride with methanol in the presence of an amine base:
POCl3 + 3 CH3 OH + 3 R3 N → PO(OCH3 )3 + 3 R3 NH+ Cl−
It is a tetrahedral molecule that is a weakly polar solvent.
Applications
Trimethyl phosphate is a mild methylating agent , useful for dimethylation of anilines and related heterocyclic compounds .[ 2] The method is complementary to the traditional Eschweiler-Clarke reaction in cases where formaldehyde engages in side reactions.
Trimethyl phosphate is used as a solvent for aromatic halogenations and nitrations as required for the preparation of pesticides and pharmaceuticals .
Other applications
It is used as a color inhibitor for fibers (e.g. polyester ) and other polymers . Trimethyl phosphate is used as a simulant for chemical weapon nerve agents .[citation needed ]
Safety considerations
With an LD50 of 2g/kg for rats, trimethylphosphate is expected to have low acute toxicity.[ 3]
References
^ D. E. C. Corbridge "Phosphorus: An Outline of its Chemistry, Biochemistry, and Technology" 5th Edition Elsevier: Amsterdam 1995. ISBN 0-444-89307-5 .
^ William A. Sheppard (1973). "m-Trifluoromethyl-N,N-dimethylaniline" . Organic Syntheses ; Collected Volumes , vol. 5, p. 1085 .
^ J. Svara, N. Weferling, T. Hofmann "Phosphorus Compounds, Organic" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2006. doi :10.1002/14356007.a19_545.pub2
External links