Isethionic acid is an
organosulfur compound
Organosulfur compounds are organic compounds that contain sulfur. They are often associated with foul odors, but many of the sweetest compounds known are organosulfur derivatives, e.g., saccharin. Nature abounds with organosulfur compounds—sulfu ...
containing an
alkyl
In organic chemistry, an alkyl group is an alkane missing one hydrogen.
The term ''alkyl'' is intentionally unspecific to include many possible substitutions.
An acyclic alkyl has the general formula of . A cycloalkyl is derived from a cycloalk ...
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 ...
located beta to a
hydroxy group
In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy ...
. Its discovery is generally attributed to
Heinrich Gustav Magnus
Heinrich Gustav Magnus (; 2 May 1802 – 4 April 1870) was a notable German experimental scientist. His training was mostly in chemistry but his later research was mostly in physics. He spent the great bulk of his career at the University of Berl ...
, who prepared it by the action of solid
sulfur trioxide
Sulfur trioxide (alternative spelling sulphur trioxide, also known as ''nisso sulfan'') is the chemical compound with the formula SO3. It has been described as "unquestionably the most important economically" sulfur oxide. It is prepared on an ind ...
on
ethanol
Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an Alcohol (chemistry), alcohol with the chemical formula . Its formula can be also written as or (an ethyl ...
in 1833.
It is a white
water-soluble
In chemistry, solubility is the ability of a substance, the solute, to form a solution with another substance, the solvent. Insolubility is the opposite property, the inability of the solute to form such a solution.
The extent of the solub ...
solid used in the manufacture of certain
surfactant
Surfactants are chemical compounds that decrease the surface tension between two liquids, between a gas and a liquid, or interfacial tension between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsifiers, foaming ...
s and in the industrial production of
taurine. It is most commonly available in the form of its sodium salt (
sodium isethionate).
Synthesis
Its original synthesis, by the reaction of
sulfur trioxide
Sulfur trioxide (alternative spelling sulphur trioxide, also known as ''nisso sulfan'') is the chemical compound with the formula SO3. It has been described as "unquestionably the most important economically" sulfur oxide. It is prepared on an ind ...
on
ethanol
Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an Alcohol (chemistry), alcohol with the chemical formula . Its formula can be also written as or (an ethyl ...
,
has largely been surpassed. It may be produced by the hydrolysis of
carbyl sulfate
Carbyl sulfate is an organosulfur compound. The white solid is the product of the reaction of sulfur trioxide and ethylene. It is used in preparation of some dyes and other organosulfur compounds. Carbyl sulfate is a colorless, crystalline, hygr ...
, which is obtained by the sulfonation of
ethylene
Ethylene (IUPAC name: ethene) is a hydrocarbon which has the formula or . It is a colourless, flammable gas with a faint "sweet and musky" odour when pure. It is the simplest alkene (a hydrocarbon with carbon-carbon double bonds).
Ethylene i ...
.
:
However the most common route is the reaction of
ethylene oxide with aqueous
sodium bisulfite
Sodium bisulfite (or sodium bisulphite, sodium hydrogen sulfite) is a chemical mixture with the approximate chemical formula NaHSO3. Sodium bisulfite in fact is not a real compound, but a mixture of salts that dissolve in water to give solutions ...
, which produces the sodium salt (
sodium isethionate):
:
Reactions
Isethionic acid is used as a starting material in the industrial production of
taurine.
Dehydration of isethionic acid gives
vinylsulfonic acid
Vinylsulfonic acid is the organosulfur compound with the chemical formula CH2=CHSO3H. It is the simplest unsaturated sulfonic acid. The C=C double bond is a site of high reactivity. Polymerization gives polyvinylsulfonic acid, especially when ...
.
Derivatives
Fatty acid
In chemistry, particularly in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated or unsaturated. Most naturally occurring fatty acids have an unbranched chain of an even number of carbon atoms, fr ...
esters of isethionic acid (such as
sodium lauroyl isethionate and
sodium cocoyl isethionate
Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable isot ...
) are used as
biodegradable
Biodegradation is the breakdown of organic matter by microorganisms, such as bacteria and fungi. It is generally assumed to be a natural process, which differentiates it from composting. Composting is a human-driven process in which biodegradati ...
anionic
surfactant
Surfactants are chemical compounds that decrease the surface tension between two liquids, between a gas and a liquid, or interfacial tension between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsifiers, foaming ...
s.
These materials are much milder to skin that other sulfate based surfactants (i.e.
sodium lauryl sulfate
Sodium dodecyl sulfate (SDS) or sodium lauryl sulfate (SLS), sometimes written sodium laurilsulfate, is an organic compound with the formula . It is an anionic surfactant used in many cleaning and hygiene products. This compound is the sodium salt ...
)
making them popular for use in make-up, shampoos and ‘Dove type’ soap bars.
Isethionic acid is also used as a
counter ion in certain pharmaceutical
formulation
Formulation is a term used in various senses in various applications, both the material and the abstract or formal. Its fundamental meaning is the putting together of components in appropriate relationships or structures, according to a formul ...
s, including the
antimicrobials
hexamidine
Hexamidine is an antiseptic and disinfectant. Hexomedine is the trade name of a diisethionate solution (1/1.000) of hexamidine. Hexamidine is used primarily as its diisethionate salt, which is more water-soluble than the dihydrochloride. The dih ...
and
pentamidine
Pentamidine is an antimicrobial medication used to treat African trypanosomiasis, leishmaniasis, ''Balamuthia'' infections, babesiosis, and to prevent and treat pneumocystis pneumonia (PCP) in people with poor immune function. In African trypano ...
.
Biological importance
Studies made on dog heart slices suggested that heart tissue may be capable of converting
taurine to isethionic acid, further experiments demonstrated that this tissue may synthetize taurine from
cystine.
[{{cite journal, author=W.O Read and J.D.Welty, year=1961, title=Synthesis of Taurine and Isethionic Acid by Dog Heart Slices, journal=The Journal of Biological Chemistry, volume=237, issue=5, pages=1521–1522, doi=10.1016/S0021-9258(19)83734-1, pmid=14490797, doi-access=free]
See also
*
1,3-Propane sultone
1,3-Propane sultone is the organosulfur compound with the formula (CH2)3SO3. It is a cyclic sulfonate ester, a class of compounds called sultones. It is a readily melting colorless solid.
Synthesis
It may be prepared by the acid catalyzed reacti ...
References
Sulfonic acids
Primary alcohols