Question

How could you prepare the following compound using a starting material that contains no more than three carbons?

Short answer

A reaction followed as:

Step-by-step solution

LDA reagent

Lithium di-isopropyl amide is the most basic reagent is used to abstract the proton from the molecule. It is used in the aldol condensation to form the enolate ion from the enol or ketone by abstracting the proton for further reaction.

Formation of the compound

The given compound is formed by the acetone followed by the formation of the enolate ion than in reaction with the alkyl halide the alkyl group attaches to the enolate oxygen and the removal of the halide ion occurs and forms the desired product.

Mechanism

Mechanism followed as:

1. Acetone reacts with LDA

2. Enolate ion formed

3. Enolate reacts with ethyl bromide

4. Ethyl attack on enolate oxygen

5. Removal of bromide on desired product formed