|Preferred IUPAC name
3D model (JSmol)
CompTox Dashboard (EPA)
|Molar mass||88.106 g·mol−1|
|Boiling point||162 °C (324 °F; 435 K)|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
(what is ?)
3-Hydroxybutanal (acetaldol, aldol) is an organic compound with the formula CH3CH(OH)CH2CHO. It is classified as an aldol and the word "aldol" can refer specifically to 3-hydroxybutanal. It is formally the product of the dimerization of acetaldehyde. A thick colorless or pale-yellow liquid, it is a versatile and valuable intermediate with diverse impacts. The compound is chiral although this aspect is not often exploited.
Acetaldehyde dimerizes upon treatment with aqueous sodium hydroxide:
This is the prototypical aldol reaction.
Dehydration of 3-hydroxybutanal gives crotonaldehyde. Distillation of 3-hydroxybutanal is sufficiently forcing to effect this conversion:
Hydrogenation of 3-hydroxybutanal gives 1,3-butanediol:
This diol is a precursor to 1,3-butadiene, precursor to diverse polymers.
Polymerization of 3-hydroxybutanal is also spontaneous, but can be stopped with the addition of water.
Aldol has been used in making perfumes and in ore flotation.
It was formerly used in medicine as a hypnotic and sedative.