Protonation converts the hydroxyl group of an alcohol to a good leaving group. Suggest a mechanism for each reaction.
(E1) \rightarrow H2SO4, heat+ H2O
(SN2 or SN1) \rightarrow HBr, heat - Br + H2O
- The mechanism of reaction is given below -
When cyclohexanol is protonated in presence of acid () it gives carbonated. In second step proton is lost to give cyclohexene.
When Br- attack directly then -OH is substituted by -Br to give bromocyclohexane by 2 mechanism.
Bromocyclohexane can also obtained by mechanism. In this firs carbocation is formed by protonation of -OH group. Then Br- attacks on carbonation to give bromocyclohexane