In organic chemistry, 3-hydroxybutanal (acetaldol, aldol) is an organic compound with the formula CH3CH(OH)CH2CHO and the structure H3C−CH(OH)−CH2−CH=O. It is classified as an aldol (R−CH(OH)−CHR'−C(=O)−R") and the word "aldol" can refer specifically to 3-hydroxybutanal. It is formally the product of the dimerization of acetaldehyde (CH3CHO). A thick colorless or pale-yellow liquid, it is a versatile and valuable intermediate with diverse impacts.[2] The compound is chiral although this aspect is not often exploited.
^"3-hydroxybutanal – Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 26 March 2005. Identification and Related Records. Retrieved 13 October 2011.