[keetner]

Hi,

So, just to give you an example of a reaction:

alcohol    --- 1) H2SO4 2) HBr, peroxides ---->    1-bromo-2-ethylcyclohexane.

So, if we dehydrate the alcohol, we will get a carbocation. But the thing I'm wondering about is, if given the right circumstances, will it ALWAYS undergo a rearrangement/shift to give the more stable carbocation? Same thing with hydride shifts?

Also, this rearrangement isn't only specific to alcohols dehydration though, is it? I just don't understand why my textbook seems to focus more on it than other possible carbocation shifts...ergh. I'm pretty confused.

Any input would be greatly appreciated though - thanks in advance!

[voidSetup]

So, if we dehydrate the alcohol, we will get a carbocation. But the thing I'm wondering about is, if given the right circumstances, will it ALWAYS undergo a rearrangement/shift to give the more stable carbocation? Same thing with hydride shifts?

I don't think it will always undergo rearrangement, it kind of depends on the rate of that step of the reaction.  You could just get a mixture of products though, some with the hydride/alkyl shift and some without.

Also, this rearrangement isn't only specific to alcohols dehydration though, is it? I just don't understand why my textbook seems to focus more on it than other possible carbocation shifts...ergh

It is not only specific to alcohol dehydration.  Think about the solvent's influence on stabilizing the carbocation.