Chapter 10, Problem 10.21P

Interpretation Introduction

Interpretation:

The ether formed in the given reaction with detailed mechanism is to be drawn.

Concept introduction:

The formation of ether by dehydration of an alcohol proceeds with the proton transfer process which converts $\text{OH}$ to a good leaving group ${\text{H}}_{\text{2}}\text{O}$. In the second step, the $\text{OH}$ group of the second molecule of alcohol acts as a nucleophile and attacks on the carbon attached to the leaving group ${\text{H}}_{\text{2}}\text{O}$. If the substrate is a diol (a molecule with two $\text{OH}$ groups that can form larger stable cyclic ether), one $\text{OH}$ is converted to the leaving group by protonation, and the second $\text{OH}$ acts as a nucleophile. In the substrate, if the leaving group is attached to benzylic carbon atom, then the reaction proceeds with ${\text{S}}_{\text{N}}\text{1}$ mechanism via formation of resonance stabilized carbocation.