The Claisen condensation involves the reaction of esters [1] in a basic medium to form 3-ketoesters [2]
Mechanism:
Step 1. Formation of the ester enolate
Step 2. Nucleophilic addition
Stage 3. Ethoxide removal
The displacement of the equilibria is produced by the subtraction of the acid hydrogen in the final keto ester, forming an enolate that is protonated in the second stage.
