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cyclohexene synthesis

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polly:
Hi,

In lab, we used cyclohexanol with H3PO4 as a catalyst to prepare cyclohexene.  My question is why does the equilibrium strongly favor the reverse reaction, hydration of the alkene?  Does it have to do with a double bond which is less stable?  Also, would you expect the rate of the acid catalyzed dehydration of 1-methylcyclohexanol to be slower, faster or about the same as for cyclohexanol?  I think the answer is slower but I am not sure I understand why.  Thank you!

Edit: edited title for better indexing. Mitch

GCT:
The equilibrium is a result of pi bond electron density availability combined with the presence of oxidizing agents.  It does not have anything is particular to do with the stability of one compound over another.

polly:
so your saying the equilibrim strongly favors hydration of an alkene because the pi bond electron density is readily available??  confused...

GCT:
I should have been more specific.  You should study the mechanism of acid catalyzed dehydration.  For instance if there was a base present, the reaction would have favored the products I presume through an E2 reaction.  However, since no strong base is present (as required by E2 reactions) one needs to supply heat for the reaction to favor the products.  Remember that dehydration also requires the removal of an hydrogen atom and involves the formation of acarbocation.

polly:
i am really trying to understand this... hydration of the alkene is favored bc it is easier to do as opposed to dehydration which requires heat??

also, the rate of acid catalyzed dehydration of 1-methylcyclohexanol is slower then cyclohexanol bc there is a tertiary carbocation?

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