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Synthesis of Ethers via Acid-catalysed Condensation of Alcohols

ether synthesis by alcohol condensation

Reaction type: Nucleophilic Substitution (SN2)

Summary

QUESTIONS:
Why can this reaction be termed a condensation reaction ? ANSWER
Why is the reaction unsuitable for unsymmetrical ether synthesis ? ANSWER
What is the most likely side reaction that will compete with the substitution ? ANSWER

Related reactions

MECHANISM FOR ALCOHOL CONDENSATION TO GIVE AN ETHER
Step 1:
An acid/base reaction. Protonation of the alcoholic oxygen to make a better leaving group. This step is very fast and reversible.  The lone pairs on the oxygen make it a Lewis base.
acid-catalysed alcohol condensation mechanism
Step 2:
The O of the second alcohol molecule functions as the nucleophile and attacks to displace the good leaving group, a neutral water molecule, by cleaving the C-O bond. This creates an oxonium ion intermediate.
Step 3:
Another acid / base reaction. The proton is removed by a suitable base (here a water molecule, ROH is another alternative) to give the ether product.

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© Dr. Ian Hunt, Department of Chemistry, University of Calgary