Show how you would use an aldol, Claisen, or another type of condensation to make each compound.
(b)

Verified step by step guidance

1. Step 1: Identify the target molecule and analyze its structure. The compound contains a β-keto ester functional group, which suggests it can be synthesized using a Claisen condensation reaction. The two cyclopentyl groups indicate that the starting materials should include cyclopentanone and ethyl acetate.
2. Step 2: Select the starting materials. For a Claisen condensation, you need an ester with an α-hydrogen (ethyl acetate) and a ketone (cyclopentanone) that can act as the nucleophile.
3. Step 3: Set up the reaction conditions. Use a strong base, such as sodium ethoxide (NaOEt), to deprotonate the α-hydrogen of ethyl acetate, forming an enolate ion. This enolate will act as the nucleophile in the reaction.
4. Step 4: Perform the Claisen condensation. The enolate ion attacks the carbonyl carbon of cyclopentanone, forming a new C-C bond. After the reaction, protonation restores the β-keto ester functional group.
5. Step 5: Purify the product. After the reaction is complete, the mixture is acidified to neutralize the base and isolate the β-keto ester product. Techniques such as recrystallization or distillation can be used to purify the compound.

Key Concepts

Aldol Condensation

Aldol condensation is a reaction between aldehydes or ketones that contain alpha-hydrogens, leading to the formation of β-hydroxy aldehydes or ketones. This reaction involves the nucleophilic addition of an enolate ion to a carbonyl compound, followed by dehydration to yield an α,β-unsaturated carbonyl compound. It is a key method for forming carbon-carbon bonds and is widely used in organic synthesis.

Claisen Condensation

Claisen condensation is a reaction between two esters or an ester and a carbonyl compound in the presence of a strong base, resulting in the formation of a β-keto ester or a β-diketone. The reaction involves the formation of an enolate ion from one ester, which then attacks the carbonyl carbon of the other ester. This reaction is significant for building complex molecules and is a fundamental reaction in organic chemistry.

Condensation Reactions

Condensation reactions are a class of reactions where two molecules combine to form a larger molecule, typically with the loss of a small molecule such as water or alcohol. In organic chemistry, these reactions are crucial for synthesizing larger, more complex structures from simpler precursors. Understanding the mechanisms and conditions for these reactions is essential for effective synthesis in organic chemistry.