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Topic: keto-enol mechanism  (Read 6587 times)

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Offline justforme

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keto-enol mechanism
« on: July 04, 2006, 03:13:42 AM »
can anyone explain how the mechanism works?as in how the electrons moves and forms a resonance structure thx  ;)

Offline Albert

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Re: keto-enol mechanism
« Reply #1 on: July 04, 2006, 11:30:45 AM »

Offline victor

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Re: keto-enol mechanism
« Reply #2 on: July 07, 2006, 10:35:31 AM »
What I can say is that keto-enol tautomerism is not a resonance hybrid..it's an equilibrium between two structures and usually, keto form will be preffered except for phenol. The picture posted by Albert, I think has explained the reason why keto form is more preffered.. ;D

Offline Will

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Re: keto-enol mechanism
« Reply #3 on: July 07, 2006, 10:58:54 AM »
The proton transfer can be base catalysed or acid catalysed, and each one has a different mechanism. In the acid one the carbonyl oxygen is protonated and a proton is removed from a carbon atom adjacent to the carbonyl carbon by water to form the enol. The base catalysed mechanism is very similar, just the proton is removed from the carbon atom adjacent to the carbonyl carbon forming an enolate anion (the negative charge is delocalised but most of it is the oxyanion as it is more stable) and that can be protonated by water to give the enol.

Search keto enol mechanism in google images for a few examples.

Offline justforme

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Re: keto-enol mechanism
« Reply #4 on: July 11, 2006, 02:22:09 AM »
thank a lot for the help from u guys and sorry for the late reply >.<

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