Tetramethoxymethane

Names
	Preferred IUPAC name Tetramethoxymethane
	Other names Tetramethyl orthocarbonate
Identifiers
CAS Number	1850-14-2;
3D model (JSmol)	Interactive image;
ChemSpider	67188;
ECHA InfoCard	100.015.853
EC Number	217-438-5;
PubChem CID	74613;
UNII	FHC4GZ2SYJ ;
UN number	3272
CompTox Dashboard (EPA)	DTXSID70171695 ;
	InChI InChI=1S/C5H12O4/c1-6-5(7-2,8-3)9-4/h1-4H3 Key: AHJWSRRHTXRLAQ-UHFFFAOYSA-N;
	SMILES COC(OC)(OC)OC;
Properties
Chemical formula	C5H12O4
Molar mass	136.15 g·mol−1
Appearance	colourless liquid[1]
Density	1.023 g/cm3 (25 °C)
Melting point	−5.5 °C[1]
Boiling point	114 °C[1]
Hazards
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H225, H315, H319, H335
Precautionary statements	P210, P261, P305+P351+P338
Related compounds
Other cations	Tetramethoxysilane
Related compounds	Tetraethoxymethane
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Tetramethoxymethane

Tetramethoxymethane is a chemical compound which is formally formed by complete methylation of the hypothetical orthocarbonic acid C(OH)4.

Preparation

The obvious synthetic route from the tetrahalomethanes does not yield the desired product, instead giving orthoformates and a halohydrin byproduct.[2]: 13 The original preparation of the tetramethoxymethane was therefore based on chloropicrin:[1]

Because of the extreme toxicity of chloropicrin, other tetrasubstituted reactive methane derivatives were investigated as starting material for tetramethoxymethane. For example, trichloromethanesulfenyl chloride (also used as a chemical warfare agent and easily accessible from carbon disulfide and chlorine) was used:[3][4]

A less problematic synthesis is based on trichloroacetonitrile:[5][6]

Thallium methoxide reacts with carbon disulfide to give tetramethoxymethane and thallium sulfide;[7] likewise dimethyl dibutylstannate gives tetramethoxymethane and dibutyltin sulfide.[8] Further preparative methods are described in the literature.[7]

Synthesis from chloropicrin only yields about 50% product. Syntheses from trichloromethanesulfenyl chloride or trichloroacetonitrile or the thallium-sulfide route yield about 70-80% product,[3][7] but the tin-sulfide synthesis has a 95% yield.[8]

Properties

Tetramethoxymethane is a clear, colorless, aromatic-smelling, low-viscosity liquid which is stable against peroxide formation.[9]

Use

In addition to its use as a solvent, tetramethoxymethane is also used as a fuel in polymer fuel cells,[10] as an alkylating agent at elevated temperatures (180-200 °C),[11] as a transesterification reagent (but showing less reactivity than trimethoxymethane[2]), and as a reagent for the synthesis of 2-aminobenzoxazoles, which are used as molecular building blocks in pharmaceutical active ingredients used in neuroleptics, sedatives, antiemetics, muscle relaxants, fungicides and others.[12]

Depending on the substituents, the one pot reaction proceeds in "modest to excellent" yields.

References

^ a b c d H. v. Hartel, Über Existenz und Darstellung des Orthokohlensäure-tetramethylesters, Ber.dtsch.chem.Ges., 60(8), 1841 (1927), doi:10.1002/cber.19270600821.
^ a b R. H. De Wolfe, Carboxylic ortho acid derivatives: preparation and synthetic applications, Organic Chemistry, Vol. 14, Academic Press, Inc. New York – London, 1970, ISBN 978-0-12-214550-6.
^ a b H. Tieckelmann, H. W. Post, The preparation of methyl, ethyl, propyl, and butyl orthocarbonates, J. Org. Chem., 13 (2), 265-267 (1948), doi:10.1021/jo01160a014.
^ US-Patent US 4,059,656, Processes for neutralizing 2,3-dibromopropanol phosphoric acid esters contained in tris(2,3-dibromo-1-propyl) phosphate, Erfinder: M. Demarcq, Anmelder: Produits Chimiques Ugine Kuhlmann, erteilt am 22. November 1974.
^ US-Patent US 3,876,708, Orthocarbonic acid esters, Erfinder: R. Speh, W. Kantlehner, Anmelder: Akzo B.V., erteilt am 8. April 1975.
^ US-Patent US 6,825,385 B2, Process for the preparation of orthocarbonates, Erfinder: G. Fries, J. Kirchhoff, Anmelder: Degussa AG, erteilt am 30. November 2004.
^ a b c W. Kantlehner et al., Die präparative Chemie der O- und N-funktionellen Orthokohlensäure-Derivate, Synthesis; 1977(2): 73-90, doi:10.1055/s-1977-24283.
^ a b Sakai Shizuyoshi; Kobayashi Yoshihiro; Ishii Yoshio (1971) [13 April 1970]. "Reaction of dialkyltin dialkoxides with carbon disulfide at higher temperature" (PDF). Journal of Organic Chemistry. 36 (9): 1176–1180. doi:10.1021/jo00808a002.
^ K. R. Kopecky; J. Molina (1987). "Bis(dimethoxymethyl) peroxide and bis(1,1-dimethoxyethyl) peroxide". Canadian Journal of Chemistry. 65 (10): 2350. doi:10.1139/v87-392.
^ US-Patent US 6,864,001, Tetramethyl orthocarbonate fuel cells and systems and methods related thereto, Erfinder: J. Zhang, K. Colbow, Anmelder: Ballard Power Systems Inc., erteilt am 8. März 2005.
^ M. Selva et al., Esters and Orthoesters as Alkylating Agents at High Temperature. Applications to Continuous-flow Processes, J. Chem. Soc., Perkin Trans. 2, 519 (1992), doi:10.1039/P29920000519.
^ C. L. Cioffi et al., Synthesis of 2-Aminobenzoxazoles Using Tetramethyl Orthocarbonate or 1,1-Dichloro-diphenoxymethane, J. Org. Chem., 75 (2), 7942-7945 (2010), doi:10.1021/jo1017052.

[von_Hartel-1] H. v. Hartel, Über Existenz und Darstellung des Orthokohlensäure-tetramethylesters, Ber.dtsch.chem.Ges., 60(8), 1841 (1927), doi:10.1002/cber.19270600821.

[De_Wolfe-2] R. H. De Wolfe, Carboxylic ortho acid derivatives: preparation and synthetic applications, Organic Chemistry, Vol. 14, Academic Press, Inc. New York – London, 1970, ISBN 978-0-12-214550-6.

[TP-3] H. Tieckelmann, H. W. Post, The preparation of methyl, ethyl, propyl, and butyl orthocarbonates, J. Org. Chem., 13 (2), 265-267 (1948), doi:10.1021/jo01160a014.

[4] US-Patent US 4,059,656, Processes for neutralizing 2,3-dibromopropanol phosphoric acid esters contained in tris(2,3-dibromo-1-propyl) phosphate, Erfinder: M. Demarcq, Anmelder: Produits Chimiques Ugine Kuhlmann, erteilt am 22. November 1974.

[5] US-Patent US 3,876,708, Orthocarbonic acid esters, Erfinder: R. Speh, W. Kantlehner, Anmelder: Akzo B.V., erteilt am 8. April 1975.

[6] US-Patent US 6,825,385 B2, Process for the preparation of orthocarbonates, Erfinder: G. Fries, J. Kirchhoff, Anmelder: Degussa AG, erteilt am 30. November 2004.

[Rev-7] W. Kantlehner et al., Die präparative Chemie der O- und N-funktionellen Orthokohlensäure-Derivate, Synthesis; 1977(2): 73-90, doi:10.1055/s-1977-24283.

[Tin-8] Sakai Shizuyoshi; Kobayashi Yoshihiro; Ishii Yoshio (1971) [13 April 1970]. "Reaction of dialkyltin dialkoxides with carbon disulfide at higher temperature" (PDF). Journal of Organic Chemistry. 36 (9): 1176–1180. doi:10.1021/jo00808a002.

[9] K. R. Kopecky; J. Molina (1987). "Bis(dimethoxymethyl) peroxide and bis(1,1-dimethoxyethyl) peroxide". Canadian Journal of Chemistry. 65 (10): 2350. doi:10.1139/v87-392.

[10] US-Patent US 6,864,001, Tetramethyl orthocarbonate fuel cells and systems and methods related thereto, Erfinder: J. Zhang, K. Colbow, Anmelder: Ballard Power Systems Inc., erteilt am 8. März 2005.

[11] M. Selva et al., Esters and Orthoesters as Alkylating Agents at High Temperature. Applications to Continuous-flow Processes, J. Chem. Soc., Perkin Trans. 2, 519 (1992), doi:10.1039/P29920000519.

[12] C. L. Cioffi et al., Synthesis of 2-Aminobenzoxazoles Using Tetramethyl Orthocarbonate or 1,1-Dichloro-diphenoxymethane, J. Org. Chem., 75 (2), 7942-7945 (2010), doi:10.1021/jo1017052.