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Claisen Rearrangment of Aryl Allyl Ethers

the Claisen rearrangement

Reaction type : Electrocyclic reaction or sigmatropic rearrangement

Summary

Caution: Do not confuse this reaction with the Claisen condensation of esters.
 
 
MECHANISM OF CLAISEN REARRANGEMENT 
Step 1:
An electrocyclic process. Push those electrons around the 6 membered ring.... Best appreciated by starting the electron flow by having the aromatic C=C attacking the allyl C=C and displacing an O leaving group....
Claisen rearrangement of allyl aryl ethers
Step 2:
Tautomerisation of the ketone (actually a dienone) to the more stable aromatic enol, the phenol.

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