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Topic: Which intermediate is most stable?  (Read 4020 times)

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Offline Fzang

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Which intermediate is most stable?
« on: December 09, 2010, 08:18:23 PM »
Sorry for making another topic so soon but this question is the question I cannot outthink.



Compound reacts with equivalent amount of HCl. Where will hydrogen go? Both intermediates are tertiary carbocations. I'm leaning a tiny bit towards the one to the right, because I guess R-CH2-R is ever so slightly more stable than CH3-R. Yes? :o but then there's also Markovnikovs rule ringing my bells, even though it's a thumb rule rather than a any sort of law.

Offline MissPhosgene

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Re: Which intermediate is most stable?
« Reply #1 on: December 09, 2010, 08:53:10 PM »
Yes, the one on the right. Zaitsef's rule.
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Offline orgopete

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Re: Which intermediate is most stable?
« Reply #2 on: December 09, 2010, 10:08:11 PM »
It's the one on the left. Although both are tertiary, the one on the left is tertiary and allylic, hence most stable.
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Offline MissPhosgene

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Re: Which intermediate is most stable?
« Reply #3 on: December 09, 2010, 10:40:44 PM »
It's the one on the left. Although both are tertiary, the one on the left is tertiary and allylic, hence most stable.

That's right. I was thinking about the resultant product, not the intermediate. That was really dumb. More sleep.
« Last Edit: December 09, 2010, 10:53:42 PM by MissPhosgene »
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Offline Fzang

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Re: Which intermediate is most stable?
« Reply #4 on: December 10, 2010, 04:39:51 AM »
It's the one on the left. Although both are tertiary, the one on the left is tertiary and allylic, hence most stable.

I see, thanks :)

Offline kunjal8015

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Re: Which intermediate is most stable?
« Reply #5 on: December 25, 2010, 10:10:08 AM »
one on the left, pi bonds are formed with 2ndary carbon and tertiary carbonation

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