Methanedisulfonic acid is the

organosulfur compound Organosulfur chemistry is the study of the properties and synthesis of organosulfur compounds, which are organic compounds that contain sulfur. They are often associated with foul odors, but many of the sweetest compounds known are organosulfur der ...

with the formula CH₂(SO₃H)₂. It is the di

sulfonic acid In organic chemistry, sulfonic acid (or sulphonic acid) refers to a member of the class of organosulfur compounds with the general formula , where R is an organic alkyl or aryl group and the group a sulfonyl hydroxide. As a substituent, it is kn ...

methane Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The abundance of methane on Earth makes ...

. It is prepared by treatment of

methanesulfonic acid Methanesulfonic acid (MsOH, MSA) or methanesulphonic acid (in British English) is an organosulfuric, colorless liquid with the molecular formula and structure . It is the simplest of the alkylsulfonic acids (). Salts and esters of methanesul ...

with

oleum Oleum (Latin ''oleum'', meaning oil), or fuming sulfuric acid, is a term referring to solutions of various compositions of sulfur trioxide in sulfuric acid, or sometimes more specifically to disulfuric acid (also known as pyrosulfuric acid). Ol ...

. Its acid strength (pK_a) is comparable to that of

sulfuric acid Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid (English in the Commonwealth of Nations, Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen, ...

History and synthesis

The acid was first unknowingly prepared in 1833 by Gustav Magnus as a decomposition product of ethanedisulfonic acid during early attempts to synthesize

diethyl ether Diethyl ether, or simply ether, is an organic compound with the chemical formula , sometimes abbreviated as . It is a colourless, highly Volatility (chemistry), volatile, sweet-smelling ("ethereal odour"), extremely flammable liquid. It belongs ...

from

ethanol Ethanol (also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound with the chemical formula . It is an Alcohol (chemistry), alcohol, with its formula also written as , or EtOH, where Et is the ps ...

and anhydrous sulfuric acid by Magnus. Early investigations focused on ether production from alcohols and strong anhydrous acids.

Liebig Justus ''Freiherr'' von Liebig (12 May 1803 – 18 April 1873) was a Germans, German scientist who made major contributions to the theory, practice, and pedagogy of chemistry, as well as to agricultural and biology, biological chemistry; he is ...

provided a detailed overview of the various sulfonic acids obtained from these reactions, and introduced the name " ethionic acid" for the sulfooxyethanesulfonic acid previously termed "Weinschwefelsäure". Josef Redtenbacher subsequently analyzed the barium salt of MDA and coined the name (still occasionally used) methionic acid, following Liebig's convention. In 1856, Adolph Strecker analyzed various methionate salts and improved the synthesis from ether and anhydrous sulfuric acid by trapping evolving gases within the reaction vessel to maximize conversion. The same year, Buckton and Hofmann discovered a synthesis reaction from

acetonitrile Acetonitrile, often abbreviated MeCN (methyl cyanide), is the chemical compound with the formula and structure . This colourless liquid is the simplest organic nitrile (hydrogen cyanide is a simpler nitrile, but the cyanide anion is not class ...

acetamide Acetamide (systematic name: ethanamide) is an organic compound with the formula CH3CONH2. It is an amide derived from ammonia and acetic acid. It finds some use as a plasticizer and as an industrial solvent. The related compound ''N'',''N''-dime ...

with fuming sulfuric acid but didn't identify their product, designating it methylotetrasulphuric acid. developed another method in 1897, treating acetylene with fuming sulfuric acid to obtain acetaldehyde disulfonic acids, which he then decomposed to methionic acid upon boiling in alkaline solution. However, all these early synthetic routes suffered from numerous byproducts. A higher-yielding synthesis was introduced by in 1929, treating

dichloromethane Dichloromethane (DCM, methylene chloride, or methylene bichloride) is an organochlorine compound with the formula . This colorless, volatile liquid with a chloroform-like, sweet odor is widely used as a solvent. Although it is not miscible with ...

(CH₂Cl₂) with potassium sulfite under hydrothermal conditions to get a methionate salt. {{chem2, CH2Cl2 + 2 K2SO3 → CH2(SO3K)2 + 2 KCl

References

Sulfonic acids

History and synthesis

See also

References