Question

Preparation of ethers by acid dehydration of secondary or tertiary alcohols is not suitable. Why?

Answer 1

Dear student!
The formation of ether is a nucleophilic bimolecular reaction (SN2) involving the attack of alcohol molecule on a protonated alcohol.

The method is suitable for the preparation of ethers having primary alkyl groups only as the alkyl group should be unhindered and the temperature be kept low, otherwise the reaction will favors the formation of alkene.

When the alcohol is secondary or tertiary , the reaction follows SN1 pathway and produces alkene at same reaction medium as the elimination competes over substitution and as a consequence, alkenes are easily formed.