Chemistry - GOC Question with Solution | TestHub

The enol of beta-dicarbonyl compounds are more stable because of conjugation and intramolecular H-bonding. Thus, the order of stability is,

$\underset{\text{III}}{{\text{CH}}_3-\stackrel{\text{OH}}{\stackrel{|}{\text{C}}=}\text{CH}-\stackrel{\text{O}}{\stackrel{\left|\right|}{\text{C}}}-{\text{CH}}_3}>\underset{\text{II}}{{\text{CH}}_3-\text{CO}-{\text{CH}}_2-\text{CO}-{\text{CH}}_3}>\underset{\text{I}}{{\text{CH}}_2=\text{C}\left(\text{OH}\right)-{\text{CH}}_2-\text{CO}-{\text{CH}}_3}$

I is less stable as (=) bond is not in conjugation with carbonly group.

III is most stable due to conjugation of (=) bond and intramolecular hydrogen bonding.