Chapter 18.SE, Problem 46AP

Interpretation Introduction

Interpretation:

The product expected when tetrahydrofuran is cleaved by treating with HI is to be given.

Concept introduction:

Ethers are cleaved by strong acids. The cleavage takes place either by S_N¹ or S_N² mechanisms, depending upon the structure of the substrate. Ethers with only primary and secondary alkyl groups react by S_N² mechanism. The Br- or I- attacks the protonated ether at the less hindered side to yield a single alcohol and a single alkyl halide. Ethers with a tertiary, benzylic or an allylic group cleave either by S_N¹ or E1 mechanism because these can produce a stable carbocations yielding alkenes and alcohols.

To give:

The product expected when tetrahydrofuran is cleaved by treating with HI.