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Topic: Aromatic Reaction?  (Read 5760 times)

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Offline refid

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Aromatic Reaction?
« on: April 08, 2007, 01:09:00 AM »
Hi
Is this Reaction Possible?

http://bp1.blogger.com/_60ljWjzZHA0/Rhh4EEuf4tI/AAAAAAAAAQ4/WynYxD7bE8Q/s1600-h/aromatic.JPG

and is the compound aromatic(my guess is yes since the extra double bond and lone pairs of the nitro[gen] is in conjugation with the ring)

edit: nitrogen not nitro
« Last Edit: April 08, 2007, 02:18:41 PM by refid »

Offline Gius

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Re: Aromatic Reaction?
« Reply #1 on: April 08, 2007, 01:24:03 AM »
to me it looks good

as long as there is no acid catalyst that would promote the NH2 groups attacking of the carbonyl group...the reduction looks good, I believe, and the dehydration at the end forms a carbocation stabalized by resonance

Offline Gius

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Re: Aromatic Reaction?
« Reply #2 on: April 08, 2007, 01:25:20 AM »
and yes its aromatic....but there is no nitro group (that's NO2)  ;D

Offline movies

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Re: Aromatic Reaction?
« Reply #3 on: April 08, 2007, 01:07:40 PM »
The NaBH4 step is not likely to work.  If you tautomerize the ketone you get from the cyclization reaction, you would get an aromatic product.  You would then have to break aromaticity to achieve the reduction.

Offline Gius

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Re: Aromatic Reaction?
« Reply #4 on: April 08, 2007, 01:25:05 PM »
How can the ketone be tautomerized? I thought that was mostly for enols?

Offline Borek

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Re: Aromatic Reaction?
« Reply #5 on: April 08, 2007, 01:28:29 PM »
You mean - enol is in equilibrium with keto form, but keto form is not in equilibrium with enol?
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Offline movies

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Re: Aromatic Reaction?
« Reply #6 on: April 08, 2007, 01:37:41 PM »
How can the ketone be tautomerized? I thought that was mostly for enols?

The two tautomers are the ketone and the enol.  Think about acetone and its enol tautomer.

Offline Gius

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Re: Aromatic Reaction?
« Reply #7 on: April 08, 2007, 02:01:39 PM »
How can the ketone be tautomerized? I thought that was mostly for enols?

The two tautomers are the ketone and the enol.  Think about acetone and its enol tautomer.

I see what you're saying...thanks, bud

I just thought that the enol formation wouldnt be favoured in acetone because of the instability

but in this case specifically, the enol is stabalized by aromaticity...so I see what you're saying

Offline Congenial

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Re: Aromatic Reaction?
« Reply #8 on: April 08, 2007, 02:30:45 PM »
It's interesting problem!  I wonder whether the 3-hydroxyl indole gains as much stability as the Phenol after tautomerization?  Considering that the carbonyl group and the N electron pair are already conjugated with the benzene ring  and ketone is much more stable  than enol.  I have seen the following tautomerization



1 exist in majority in THF although 2 is aromatic.

For this 
Maybe 4 exists in majority in solution, but if 3 still have the minimum concentration to react with NaBH4, then the equlibrum will move toward 3, and the reduction will be completed. Just some of my opinion




« Last Edit: April 08, 2007, 02:35:52 PM by Congenial »

Offline kristo

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Re: Aromatic Reaction?
« Reply #9 on: April 11, 2007, 10:39:22 AM »
If it does indeed tautomerize then would it even be possible to isolate the final product? Or is this just theoretical?

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