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This is the answer to chapter 16, problem number 35 from the smith organic chemistry textbook.
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And in this problem, we are asked to explain why the cyclopentadine, or pardon me, dionide anion, gives only one signal in its carbon 13 nmr spectrum.
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And so in order to answer this, we're going to draw all the resonant structures for this molecule.
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And so that is going to look like this.
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So these electrons can go here.
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These electrons can go to this carbon.
00:58
Sorry, let's try that again.
01:03
There we go.
01:03
That's better.
01:06
And so when we do that, we now have our loan pair situated here with negative charge.
01:15
And so from there, the electrons, the loan pair can go there.
01:21
These electrons can go to this carbon.
01:46
And so now our double bonds will be here and here, and the loan pair will be here with the negative charge.
01:58
And so now we can move the electrons like this.
02:06
And so what you're seeing and what will be really apparent in just one more structure is that really this loan pair could be seated on any of these carbons and any of these carbons could have the double bonds going on.
02:29
And so now loan pair and negative charge here.
02:35
And so lastly, we can move electrons like this.
02:49
And so now our negative charge is here...