Question

The major product of the following reaction has the molecular formula C10H16O3. Draw its structure in the most stable tautomeric form.

The major product of the following reaction has the molecular formula C10H16O3. Draw its structure in the most stable tautomeric form.

Answer 1

Concepts and reason

A reaction is given in which a diester is reacting with sodium ethoxide followed by acidic work up. The correct product of the reaction needs to be written. Sodium ethoxide acts as a base and abstract the acidic hydrogen forming a carbanion.

Acidic hydrogen generally refers to the hydrogen which can be easily abstracted or in other words whose conjugate base formed is stable.

Fundamentals

Esters having ${\rm{\alpha - hydrogen}}$ in the presence of base undergo Claisen condensation and result in the formation ${\rm{\beta - keto}}$ ester. Consider the following reaction:

If the compound contains two ester functional group itself then the reaction is termed as Dickman Condensation, that is, intramolecular claisen condensation.

Draw the structure of the given diester and identify the acidic hydrogen that would be abstracted by the base, that is, sodium ethoxide and result in the formation of as shown below:

Write the product of the reaction by the intermolecular attack of carbanion at the carbonyl center as shown below:

Ans:

Hence, the final product of the reaction is as follows: