Chapter 16.SE, Problem 70AP

Interpretation Introduction

Interpretation:

A mechanism for the reaction of benzene with 2,2,5,5-teteamethyltetrahydrofuran shown below is to be proposed.

Concept introduction:

The reaction involves the electrophilc substitution of cyclic ether into a benzene ring. The electrophile can be produced by the protonation of the ethereal oxygen followed by a cleavage of a C-O bond. The eletrophilic attack will lead to the formation of an alcohol. Protonation of the alcohol and subsequent elimination of water generates another carbocation which can internally attack the ring. The loss of a proton from the intermediate will lead to product expected.

To propose:

A mechanism for the reaction of benzene with 2,2,5,5-teteamethyltetrahydrofuran shown.