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Topic: Thermodynamic vs kinetic enolate  (Read 1003 times)

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Offline xshadow

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Thermodynamic vs kinetic enolate
« on: December 23, 2019, 06:04:28 AM »
I have some doubts explained here :

Why the first one is the thermodynamic enolate?

Ok,in one resonance structure is more stable than the other enolate...but in the second resonance structure (the carboanionic structure)is less stable 

Some help?
Thanks!!

Offline kriggy

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Re: Thermodynamic vs kinetic enolate
« Reply #1 on: December 25, 2019, 12:17:11 PM »
AFAIK more substitued double bonds are more stable due to hyperconjugation.

Also, I think your note underneath is wrong. If A1 > B1 then A2>B2 because A1 and A2 are the same jsut drawn differently

Offline spirochete

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Re: Thermodynamic vs kinetic enolate
« Reply #2 on: December 25, 2019, 02:06:17 PM »
You use Zaitsev's rule to assess the relative stability. The greatest contributor to the resonance hybrid is generally best for comparing stability. Also, Kriggy is correct that you need to consider each enolate as one single species.

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