Acetoacetic Ester Synthesis

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Acetoacetic ester synthesis is a synthetic procedure used to convert a compound that has the general structural formula 1 into aketone that has the general structural formula 2.

R¹ = alvikyl
L = leang group

The group —CH₂COCH₃ in 2 is contributed by an acetoacetic ester, hence the term acetoacetic ester synthesis.

R² = alkyl, aryl

Acetoacetic ester synthesis consists of four consecutive reactions that can be carried out in the same pot.

reaction 1: acid-base reaction
reaction 2: nucleophilic substitution
reaction 3: ester hydrolysis (using saponification)
reaction 4: decarboxylation

eg:

reaction 1:

reaction 2:

reaction 3:

reaction 4:

A more direct method to convert 3 to 4 is the reaction of 3 with the enolate ion (5) of acetone.

However, the generation of 5 from acetone quantitatively in high yield is not an easy task because the reaction requires a very strong base, such as LDA, and must be carried out at very low temperature under strictly anhydrous conditions.