Keto-enol Tautomerism
Enols interconvert with carbonyl compounds that have an α-hydrogen, like ketones and aldehydes. The compound is deprotonated on one side and protonated on another side, whereas a single bond and a double bond are exchanged. This is called keto-enol tautomerism.
The enol form is usually unstable, does not survive long, and changes into the keto (ketone). This is because oxygen is more electronegative than carbon and thus forms stronger bonds.
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