A stepwise mechanism is to be written for the acid catalyzed formation of oxane from 1,5-pentanediol . Concept Introduction: Primary alcohols form ethers when they are heated in the presence of an acid catalyst. Two molecules of the alcohol undergo condensation and form a larger molecule, that is ether and a smaller molecule, which is water. In the first step, the alcohol is protonated by the acid catalyst producing an alkoxonium ion. In the second step, another alcohol molecule acts as a nucleophile and attacks the alkoxonium ion. In the final step, the de-protonation of alkoxonium ion takes place to form the ether molecule.

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Chapter 16.7, Problem 7P

Interpretation Introduction

Interpretation:

A stepwise mechanism is to be written for the acid catalyzed formation of oxane from 1,5-pentanediol.

Concept Introduction:

Primary alcohols form ethers when they are heated in the presence of an acid catalyst.

Two molecules of the alcohol undergo condensation and form a larger molecule, that is ether and a smaller molecule, which is water.

In the first step, the alcohol is protonated by the acid catalyst producing an alkoxonium ion.

In the second step, another alcohol molecule acts as a nucleophile and attacks the alkoxonium ion.

In the final step, the de-protonation of alkoxonium ion takes place to form the ether molecule.

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