Home > Community > Mechanism of acid-catalyzed ring opening of a cyclopropane ring
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+ Elimination
+ Chemistry
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Mickey Curran

Mechanism of acid-catalyzed ring opening of a cyclopropane ring

Cheating - Spouse/Partner  Follow

I believe the mechanism should be somewhat like this (after the formation of carbocation) -

enter image description here

It would account for the product shown, but I am not sure if it's correct. I feel it's more favourable for a dehydration to occur with the hydrogen from the ring itself (shown on the dash at the top) to form this -

enter image description here

This double bond is conjugated and more substituted, so I should have thought that this would be the major product.

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Ebhohon Victory  Follow
@Mithoron Thanks for the insight. Yes, if its a single step then to form my proposed product it would need to start making a double bond before the ring was completely broken - which of course would be difficult owing to angle strain.More
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Eashan Das  Follow
If my mechanism is wrong, please let me know.More
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Jessyca Conrad  Follow
@user55119 Great point! It shows how reading things closely matters a lot :)More
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John Barton  Follow
Probably elimination is concerted with ring opening, so "less favorable" product is created.More
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John Privett  Follow
Did the OPs question state that the observed product was the major product? No.More
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