Illustrated Glossary of Organic Chemistry

Acetoacetic ester synthesis: A reaction sequence used to form a carbon-carbon bond at the α-carbon of a ketone, starting with a β-ketoester such as ethyl acetoacetate. Especially useful to minimize side products from aldol reactions or excessive alkylation.

Acetoacetic Ester Synthesis Sequence for the Preparation of 4-Phenyl-2-Butanone


Ethyl acetoacetate is converted to its enolate with sodium ethoxide, a strong base.


The enolate is alkylated with benzyl bromide (PhCH₂Br) in an S_N2 reaction.


  Base or acid hydrolysis converts the β-keto ester to a β-keto acid.


Decarboxylation of the β-keto acid gives the ketone product.