Are you an EPFL student looking for a semester project?
Work with us on data science and visualisation projects, and deploy your project as an app on top of Graph Search.
Concept
Dimethyl sulfate
Summary
Dimethyl sulfate (DMS) is a chemical compound with formula (CH3O)2SO2. As the diester of methanol and sulfuric acid, its formula is often written as (CH3)2SO4 or Me2SO4, where CH3 or Me is methyl. Me2SO4 is mainly used as a methylating agent in organic synthesis.
Me2SO4 is a colourless oily liquid with a slight onion-like odour (although smelling it would represent significant exposure). Like all strong alkylating agents, Me2SO4 is extremely toxic. Its use as a laboratory reagent has been superseded to some extent by methyl triflate, CF3SO3CH3, the methyl ester of trifluoromethanesulfonic acid.
Dimethyl sulfate was discovered in the early 19th century in an impure form. J. P. Claesson later extensively studied its preparation.
It was investigated as a candidate for possible use in chemical warfare in World War I in 75% to 25% mixture with methyl chlorosulfonate (CH3ClO3S) called "C-stoff" in Germany, or with chlorosulfonic acid called "Rationite" in France.
Dimethyl sulfate can be synthesized in the laboratory by several methods, the simplest being the esterification of sulfuric acid with methanol:
2 CH3OH + H2SO4 → (CH3)2SO4 + 2 H2O
At higher temperatures, dimethyl sulfate decomposes.
The reaction of methyl nitrite and methyl chlorosulfonate also results in dimethyl sulfate:
CH3ONO + (CH3)OSO2Cl → (CH3)2SO4 + NOCl
Dimethyl sulfate has been produced commercially since the 1920s. A common process is the continuous reaction of dimethyl ether with sulfur trioxide.
(CH3)2O + SO3 → (CH3)2SO4
Dimethyl sulfate is a reagent for the methylation of phenols, amines, and thiols. One methyl group is transferred more quickly than the second. Methyl transfer is assumed to occur via an SN2 reaction. Compared to other methylating agents, dimethyl sulfate is preferred by the industry because of its low cost and high reactivity.
Commonly Me2SO4 is employed to methylate phenols.
Official source
About this result
This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.