September 28, 2020, 06:40:18 PM
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Topic: Diels-Alder pericyclic reaction mechanism proof check  (Read 212 times)

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Offline Traumatic Acid

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Diels-Alder pericyclic reaction mechanism proof check
« on: September 14, 2020, 02:31:51 AM »
G'day ladies and germs.
I've been trying to figure out the mechanism behind the reaction between 2,3,4,5-Tetraphenylcyclopentadienone and dimethylacetylenedicarboxylate to form dimethyl-3,4,5,6-tetraphenylphthalate catalysed by dimethylformamide. That hurts to read so I will attach a photo of the general reaction.

My question is whether my working out of the mechanism (attached) is correct?
Steps 1 and 2 sure would not occur under normal conditions, so if someone could explain to me a bit about dimethylformamide that would be much appreciated.

Thanks :)

Offline AWK

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Re: Diels-Alder pericyclic reaction mechanism proof check
« Reply #1 on: September 14, 2020, 02:48:17 AM »
Why are you opening the cyclopentadienone ring? The Diels-Alder reaction is followed by thermal decarbonylation.
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Offline Traumatic Acid

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Re: Diels-Alder pericyclic reaction mechanism proof check
« Reply #2 on: September 14, 2020, 09:40:31 PM »
More like this?

Offline AWK

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Re: Diels-Alder pericyclic reaction mechanism proof check
« Reply #3 on: September 15, 2020, 02:57:54 AM »
OK
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Offline wildfyr

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Re: Diels-Alder pericyclic reaction mechanism proof check
« Reply #4 on: September 16, 2020, 08:18:08 AM »
Your first step arrows do not lead to the product shown in the second step. You never show the C-C bond breaking.

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