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Topic: Resonance questions  (Read 2777 times)

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Offline Nitin_Naudiyal

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Resonance questions
« on: May 18, 2012, 03:49:43 AM »
Please help me with this problem.

Offline JustinCh3m

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Re: Resonance questions
« Reply #1 on: May 18, 2012, 06:27:14 PM »
the first structure is BY FAR the best structure because the benzene ring has 6 pi electrons (4n +2) - special stability of being aromatic.  The other resonance structures are neither aromatic not antiaromatic (4n) because there are now 7 pi electrons in the cyclic, conjugated array of p-orbitals.  It's just an "ordinary compound" - not aromatic, not antiaromatic.

Offline Dan

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Re: Resonance questions
« Reply #2 on: May 19, 2012, 08:08:31 AM »
Here is a better picture, which might make things clearer:

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Offline juanrga

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Re: Resonance questions
« Reply #3 on: May 19, 2012, 11:49:54 AM »
Please help me with this problem.

I would add that a resonance is a representation of what is happening. The molecule is not in one of those forms and then jumps to another. You cannot say that the "bond shift". The molecule is in a quantum mixture of all the resonant forms.
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