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Topic: Dehydration of the following 2nd order alcohol with conc hcl....  (Read 1733 times)

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Offline Bjc51192

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Dehydration with conc HCL gives rise to a tetra substituted alkene what is the stucture of this alkene?



Problem number 8

This was on my exam today. I tried doing a hydride shift but I didn't get a tetra substituted alkene. Time was up So I panicked and moved a alkyl group forming it as if it was tetra-substituted but I am not sure.


Thanks for the help

Offline orgopete

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Re: Dehydration of the following 2nd order alcohol with conc hcl....
« Reply #1 on: March 28, 2013, 10:44:21 PM »
If a hydride shift were to occur, it could give a tertiary carbocation adjacent to two cyclopentane rings. Cannot loss of a proton give a tetra-substituted alkene?
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Offline Bjc51192

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Re: Dehydration of the following 2nd order alcohol with conc hcl....
« Reply #2 on: March 28, 2013, 11:01:44 PM »
Tried that, for some reason I still don't see it. Wow... unless if the cyclopentane ring is not counted as 1 but simply the carbons attached. If so I am so mad I got that question wrong....

Offline orgopete

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Re: Dehydration of the following 2nd order alcohol with conc hcl....
« Reply #3 on: March 29, 2013, 09:32:40 AM »
If a hydride gave a tertiary carbocation, then loss of a proton from the cyclopentane should give a tetra-substituted double bond, RCH2, C5H9, and CH2CH2CH2CH2.
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