Which of the compounds has the highest percentage of enol?
How do I compare these?
You could expect higher enol content in the following cases:
1.If there is an active methylene group ( or any other acidic $\ce{C-H}$ bond )
2.Extended conjugation in the enol form
3.Attainment of aromaticity after enolisation
4.Any intramolecular hydrogen bonding possibility in the enol form
Coming to your question:
3,4 - there's no α-hydrogen (no enolisable hydrogen).So, no tautomerisation takes place
1- has 99% keto content
2- is expected to have more enol content due to extended conjugation of the π-electrons of the double bond formed after enolisation with the phenyl rings.
ANS: 2 has the highest enol content.
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Tapi
Updated on January 30, 2023Comments
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Tapi 4 months
Which of the compounds has the highest percentage of enol?
$\ce{CH3-CHO}$
$\ce{Ph2-CH-CHO}$
$\ce{Ph-CO-Ph}$
Parabenzoquinone
How do I compare these?