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Topic: Why will this reaction not occur?  (Read 2500 times)

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Offline akaEMILY

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Why will this reaction not occur?
« on: October 11, 2012, 06:09:44 PM »
B(CH3)3 + [(CH3)3C]2O

B(CH3)3 is a lewis acid.. I just don't understand why it wouldn't occur. Would it be too unstable to exist?

Offline akaEMILY

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Why will this lewis acid reaction not occur?
« Reply #1 on: October 11, 2012, 06:20:23 PM »
Sorry about the repost. I posted this in general chem but realized I could get a more specific answer in organic.

B(CH3)3 + [(CH3)3C]2O

B(CH3)3 is a lewis acid.. I just don't understand why it wouldn't occur. Would it be too unstable to exist?

Offline Arkcon

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Re: Why will this lewis acid reaction not occur?
« Reply #2 on: October 11, 2012, 09:31:59 PM »
We don't need two. http://www.chemicalforums.com/index.php?topic=62723.0;topicseen So I will merge them.  But next time, akaEMILY: don't cross-post.
« Last Edit: October 12, 2012, 10:30:36 AM by Arkcon »
Hey, I'm not judging.  I just like to shoot straight.  I'm a man of science.

Offline Hunter2

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Re: Why will this reaction not occur?
« Reply #3 on: October 12, 2012, 01:05:55 AM »
The ether is a big molecule. Probably steric problems.

Offline orgopete

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Re: Why will this reaction not occur?
« Reply #4 on: October 12, 2012, 08:51:56 AM »
This is an interesting combination of effects. The chemistry of boron is consistent with becoming tetrahedral, for example boric acid B(OH)4(-) + H(+), BF4(-), BH4(-). That explains why trivalent boron compounds are Lewis acids. In this case, methyl groups are attached which donate electrons and reduce the Lewis acidity of boron.

Di-t-butylether is probably very easy to protonate and therefore generate a tertiary carbocation. Even with a weak Lewis acid, I might think B(CH3)3 would be sufficient to cleave t-butylether.

Could someone confirm the actual experiment results? What did or did not happen? How was the experiment done?
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Offline orgopete

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Re: Why will this lewis acid reaction not occur?
« Reply #5 on: October 12, 2012, 08:54:16 AM »
I posted an answer in the general chemistry forum linked by Arkcon. I think this may have been a better topic in organic chemistry. Would it have formed a carbocation?
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