Question

Describe how the following compound can be synthesized from compounds containing no more than six carbons.

Short answer

The given compound can be synthesized from compounds containing no more than six carbons because the target molecule is a 1,5-dioxygenated compound, a negatively charged α-carbon using enamine as the synthetic equivalent and an α,β-unsaturated ketone can be used in its synthesis.

Step-by-step solution

Michael Addition

The nucleophilic addition of carbanions (enols and enolates) to the double bond of α,β-unsaturated carbonyl compound is known as Michael addition also known as conjugated addition.

Michael addition is a very good way of making 1,5-difunctionalized compound

Enamine synthesis

Enamine is formed when an aldehyde or a ketone reacts with a secondary amine.

Enamines as specific enol equivalents are particularly useful for conjugate addition as they are soft nucleophiles but are more reactive than enols. The steps involved in the synthesis are:

• The carbonyl compound is converted to an enamine by treating it with a secondary amine in the presence of a trace amount of acid.

• The product obtained is enamine, which can be converted into corresponding carbonyl by mild hydrolysis.

• The main advantage to using an enamine intermediate to alkylate an aldehyde or a ketone is that it forms a monoalkylated product without having to use a strong base (LDA).

Describe the synthesis of the following given compound

The given compound can be synthesized from compounds containing no more than six carbons because the target molecule is a 1,5-dioxygenated compound, a negatively charged α-carbon using enamine as the synthetic equivalent and an α,β-unsaturated ketone can be used in its synthesis.