An addition
compound formed between an aldehyde
or ketone and hydrogen cyanide. The
general formula is RCH(OH)(CN) (from
an aldehyde) or RR′C(OH)(CN) (from a
ketone). Cyanohydrins are easily hydrolyzed
to hydroxycarboxylic acids. For
instance, the compound 2-hydroxypropanonitrile
(CH3CH(OH)(CN)) is hydrolyzed
to 2-hydroxypropanoic acid
(CH3CH(OH)(COOH)).