3-Hydroxybutanal (acetaldol) is an
organic compound
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 ...
with the formula CH
3CH(OH)CH
2CHO. It is classified as an
aldol
In organic chemistry, an aldol describes a structural motif consisting of a 3-hydroxy ketone or 3-hydroxyaldehyde. Aldols are usually the product of aldol addition. When used alone, the term "aldol" may refer to 3-hydroxybutanal.
Stereochemistr ...
, formally the product of the
dimerization
A dimer () (''wikt:di-, di-'', "two" + ''-mer'', "parts") is an oligomer consisting of two monomers joined by bonds that can be either strong or weak, Covalent bond, covalent or Intermolecular force, intermolecular. Dimers also have significant im ...
of
acetaldehyde
Acetaldehyde (IUPAC systematic name ethanal) is an organic chemical compound with the formula CH3 CHO, sometimes abbreviated by chemists as MeCHO (Me = methyl). It is a colorless liquid or gas, boiling near room temperature. It is one of the mos ...
. A colorless liquid, it is a versatile and valuable intermediate with diverse impacts.
[ The compound is chiral although this aspect is not often exploited.
]
Production
Acetaldehyde dimerizes upon treatment with aqueous sodium hydroxide:[
:2CH3CHO → CH3CH(OH)CH2CHO + H2O
]
Reactions and uses
Dehydration of 3-hydroxybutanal gives crotonaldehyde
Crotonaldehyde is a chemical compound with the formula CH3CH=CHCHO. The compound is usually sold as a mixture of the ''E''- and ''Z''-isomers, which differ with respect to the relative position of the methyl and formyl groups. The ''E''-isomer ...
. Distillation of 3-hydroxybutanal is sufficiently forcing to effect this conversion:butanediol Butanediol, also called butylene glycol, may refer to any one of four stable structural isomers:
* 1,2-Butanediol
* 1,3-Butanediol
*1,4-Butanediol
*2,3-Butanediol
2,3-Butanediol is the organic compound with the formula (CH3CHOH)2. It is classif ...
:
:CH3CH(OH)CH2CHO + H2 → CH3CH(OH)CH2CH2OH
This diol is a precursor to 1,3-butadiene
1,3-Butadiene () is the organic compound with the formula (CH2=CH)2. It is a colorless gas that is easily condensed to a liquid. It is important industrially as a precursor to synthetic rubber. The molecule can be viewed as the union of two viny ...
, precursor to diverse polymers.
Polymerization of 3-hydroxybutanal is also spontaneous, but can be stopped with the addition of water.
Former or niche uses
It was formerly used in medicine as a hypnotic
Hypnotic (from Greek ''Hypnos'', sleep), or soporific drugs, commonly known as sleeping pills, are a class of (and umbrella term for) psychoactive drugs whose primary function is to induce sleep (or surgical anesthesiaWhen used in anesthesia ...
and sedative
A sedative or tranquilliser is a substance that induces sedation by reducing irritability or excitement. They are CNS depressants and interact with brain activity causing its deceleration. Various kinds of sedatives can be distinguished, but t ...
.
See also
* 4-Hydroxybutanal
References
Hydroxy aldehydes
GABA analogues
Hypnotics
Sedatives
Aldols
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