Hydroxyacetone, also known as acetol, is the
organic chemical
In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The st ...
with the formula CH
3C(O)CH
2OH. It consists of a
primary alcohol
A primary alcohol is an alcohol in which the hydroxy group is bonded to a primary carbon atom. It can also be defined as a molecule containing a “–CH2OH” group.
In contrast, a secondary alcohol has a formula “–CHROH” and a tertiary ...
substituent on
acetone
Acetone (2-propanone or dimethyl ketone), is an organic compound with the formula . It is the simplest and smallest ketone (). It is a colorless, highly volatile and flammable liquid with a characteristic pungent odour.
Acetone is miscib ...
. It is an
α-hydroxyketone, also called a ketol, and is the simplest
hydroxy ketone
In organic chemistry a hydroxy ketone (often referred to simply as a ketol) is a functional group consisting of a ketone flanked by a hydroxyl group. In the two main classes, the hydroxyl group can be placed in the alpha position (an alpha-hydroxy ...
structure. It is a colorless, distillable liquid.
Preparation
It is produced commercially by dehydration of
glycerol
Glycerol (), also called glycerine in British English and glycerin in American English, is a simple triol compound. It is a colorless, odorless, viscous liquid that is sweet-tasting and non-toxic. The glycerol backbone is found in lipids known ...
.
Hydroxyacetone is commercially available, but it also may be synthesized on a laboratory scale by a
substitution reaction
A substitution reaction (also known as single displacement reaction or single substitution reaction) is a chemical reaction during which one functional group in a chemical compound is replaced by another functional group. Substitution reactions ar ...
on
bromoacetone
Bromoacetone is an organic compound with the formula . It is a colorless liquid although impure samples appear yellow or even brown. It is a lachrymatory agent and a precursor to other organic compounds.
Occurrence in nature
Bromoacetone is pre ...
.
Reactions
It undergoes rapid
polymerization
In polymer chemistry, polymerization (American English), or polymerisation (British English), is a process of reacting monomer, monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. There are ...
, including forming a
hemiacetal
A hemiacetal or a hemiketal has the general formula R1R2C(OH)OR, where R1 or R2 is hydrogen or an organic substituent. They generally result from the addition of an alcohol to an aldehyde or a ketone, although the latter are sometimes called hemike ...
cyclic
dimer
Dimer may refer to:
* Dimer (chemistry), a chemical structure formed from two similar sub-units
** Protein dimer, a protein quaternary structure
** d-dimer
* Dimer model, an item in statistical mechanics, based on ''domino tiling''
* Julius Dimer ...
. Under
alkaline
In chemistry, an alkali (; from ar, القلوي, al-qaly, lit=ashes of the saltwort) is a base (chemistry), basic, ionic compound, ionic salt (chemistry), salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as ...
conditions, it undergoes a rapid
aldol condensation
An aldol condensation is a condensation reaction in organic chemistry in which two carbonyl moieties (of aldehydes or ketones) react to form a β-hydroxyaldehyde or β-hydroxyketone (an aldol reaction), and this is then followed by dehydration to ...
.
Hydroxyacetone can be produced by degradation of various sugars. In foods, it is formed by the
Maillard reaction
The Maillard reaction ( ; ) is a chemical reaction between amino acids and reducing sugars that gives browned food its distinctive flavor. Seared steaks, fried dumplings, cookies and other kinds of biscuits, breads, toasted marshmallows, and man ...
. It reacts further to form other compounds with various aromas.
As such it finds some use as a flavoring.
See also
*
Acyloin
Acyloins or α-hydroxy ketones are a class of organic compounds which all possess a hydroxy group adjacent to a ketone group. The name acyloin is derived from the fact that they are formally derived from reductive coupling of carboxylic acyl gro ...
, the simplest secondary α-hydroxy ketone.
References
External links
*{{Commonscatinline
Alpha-hydroxy ketones