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Topic: keto-enol tautomerism  (Read 1655 times)

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Offline HB

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keto-enol tautomerism
« on: November 22, 2013, 12:38:56 PM »
why is the keto form of acetone is more stable than enol form

Offline orgopete

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Re: keto-enol tautomerism
« Reply #1 on: November 22, 2013, 01:09:12 PM »
I don't know the molecular orbital argument, but I think you could expect this result for a practical reason. Water is more acidic than methane, electrons are more pulled toward an oxygen nucleus because it has more protons. If the keto and enol form were in equilibrium, the equilibrium would shift toward the less acidic C-H bonds from O-H bonds.
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Offline zsinger

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Re: keto-enol tautomerism
« Reply #2 on: November 22, 2013, 04:34:57 PM »
A ketone formation rxn. is the very strongly entropically favored.  For instance, most nucleophilic substitutions are driven by the RE-formation of the ketone species.  Hope this helps.
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