When trans-2-methylcyclohexanol is subjected to acid-catalyzed dehydration, the major product is 1-methylcyclohexene.
However, when trans-1-bromo-2-methylcyclohexane is subjected to dehydrohalogenation, the major product is 3-methylcyclohexene.
The attempt at a solution
Obviously, this is an E1 mechanism and the hydride shifts occur from either of the adjacent (to the carbocation) carbons in each case.
Also, -Br is a much better leaving group than -OH (but I don't know if it's relevant here).
The 3° hydrogen in case 2 is more acidic due to the greater -I effect of -Br. Right?
How will this affect the outcome of the reaction?
How can we account for the different outcomes anyway?
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