Chapter 9, Problem 9.62P

Interpretation Introduction

Interpretation:

A complete mechanism for the given reaction is to be provided.

Concept introduction:

Under acidic conditions, an ether is protonated, converting the oxygen into a better leaving group and the adjacent carbon into an electrophile. The oxygen is bonded to a primary carbon. Therefore, its substitution will occur via the ${\text{S}}_{\text{N}}\text{2}$ mechanism. Once the ether oxygen is protonated and converted to a better leaving group, the nucleophile ethanol will attack the adjacent carbon, opening the ring. A second substitution can take place, replacing the $-\text{OH}$ group at the other end of the opened chain by a second ethoxide to give a disubstituted product.