tetramethoxymethane

The obvious synthetic route from the tetrahalomethanes does not yield the desired product, instead giving orthoformates and a halohydrin byproduct.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}}.{{rp|p=13}} The original preparation of the tetramethoxymethane was therefore based on chloropicrin:

:File:TMOC from chloropicrin corr.svg

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 bisulfide and chlorine) was used: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, [http://www.google.co.uk/patents/US4059656 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.

:File:TMOC from trichlorsulfenylchloride.svg

A less problematic synthesis is based on trichloroacetonitrile:US-Patent US 3,876,708, [http://www.google.co.uk/patents/US3876708 Orthocarbonic acid esters], Erfinder: R. Speh, W. Kantlehner, Anmelder: Akzo B.V., erteilt am 8. April 1975.US-Patent US 6,825,385 B2, [http://www.google.co.uk/patents/US6825385 Process for the preparation of orthocarbonates], Erfinder: G. Fries, J. Kirchhoff, Anmelder: Degussa AG, erteilt am 30. November 2004.

:File:TMOC aus Trichloracetonitril.svg

Thallium methoxide reacts with carbon disulfide to give tetramethoxymethane and thallium sulfide; likewise dimethyl dibutylstannate gives tetramethoxymethane and dibutyltin sulfide.{{cite journal|url=https://www.ic.unicamp.br/~stolfi/realwork/EXPORT/projects/wikipedia/ancient_alphabets/00-DOCS/sakai-et-al-2002-reaction-of-dialkyltin-dialkoxides-with-carbon-disulfide-at-higher-temperature-preparation-of.pdf|pages=1176–1180|journal=Journal of Organic Chemistry|volume=36|issue=9|year=1971|title=Reaction of dialkyltin dialkoxides with carbon disulfide at higher temperature|author1=Sakai Shizuyoshi|author2=Kobayashi Yoshihiro|author3=Ishii Yoshio|doi=10.1021/jo00808a002 |orig-date=13 April 1970}} Further preparative methods are described in the literature.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}}.

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

Tetramethoxymethane is a clear, colorless, aromatic-smelling, low-viscosity liquid which is stable against peroxide formation.{{cite journal|journal=Canadian Journal of Chemistry|author=K. R. Kopecky|author2= J. Molina |title=Bis(dimethoxymethyl) peroxide and bis(1,1-dimethoxyethyl) peroxide |year=1987 |volume=65 |issue=10 |page=2350 |doi=10.1139/v87-392 }}

In addition to its use as a solvent, tetramethoxymethane is also used as a fuel in polymer fuel cells,US-Patent US 6,864,001, [https://patents.google.com/patent/US6864001 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. as an alkylating agent at elevated temperatures (180-200 °C),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}}. as a transesterification reagent (but showing less reactivity than trimethoxymethane), 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.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}}.

Aminobenzoxazole aus Orthocarbonaten

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

Category:Orthocarbonates

Category:Methoxy compounds