Table of contents

1. A Review of General Chemistry5h 5m
2. Molecular Representations1h 14m
3. Acids and Bases2h 46m
4. Alkanes and Cycloalkanes4h 17m
5. Chirality3h 39m
6. Thermodynamics and Kinetics1h 22m
7. Substitution Reactions1h 48m
8. Elimination Reactions2h 30m
9. Alkenes and Alkynes2h 9m
10. Addition Reactions3h 19m
11. Radical Reactions1h 58m
12. Alcohols, Ethers, Epoxides and Thiols2h 42m
13. Alcohols and Carbonyl Compounds2h 17m
14. Synthetic Techniques1h 26m
15. Analytical Techniques:IR, NMR, Mass Spect7h 3m
16. Conjugated Systems6h 13m
17. Ultraviolet Spectroscopy51m
18. Aromaticity2h 34m
19. Reactions of Aromatics: EAS and Beyond5h 1m
20. Phenols55m
21. Aldehydes and Ketones: Nucleophilic Addition4h 56m
22. Carboxylic Acid Derivatives: NAS2h 51m
23. The Chemistry of Thioesters, Phophate Ester and Phosphate Anhydrides1h 10m
24. Enolate Chemistry: Reactions at the Alpha-Carbon1h 53m
25. Condensation Chemistry2h 9m
26. Amines1h 43m
27. Heterocycles2h 0m
28. Carbohydrates5h 53m
29. Amino Acids4h 20m
30. Peptides and Proteins2h 42m
31. Catalysis in Organic Reactions1h 30m
32. Lipids 2h 50m
33. The Organic Chemistry of Metabolic Pathways2h 52m
34. Nucleic Acids1h 32m
35. Transition Metals6h 14m
36. Synthetic Polymers1h 49m

25. Condensation Chemistry

Intramolecular Aldol Condensation

Organic Chemistry

25. Condensation Chemistry

Intramolecular Aldol Condensation

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7:07 minutes

Problem 32e

Textbook Question

Show how each compound can be dissected into reagents joined by an aldol condensation, then decide whether the necessary aldol condensation is feasible.
(e)

Verified step by step guidance

Step 1: Analyze the given compound structure. The compound contains a ketone functional group (C=O) and an α,β-unsaturated system (double bond adjacent to the carbonyl group). This suggests that the compound could be formed via an aldol condensation reaction.

Step 2: Identify the two fragments that could combine to form the given compound. In an aldol condensation, one fragment acts as the enolate ion (nucleophile) and the other as the electrophile (carbonyl compound). Here, the enolate ion would likely form from the methyl ketone group (CH3CO-) and the electrophile would be cyclohexanone.

Step 3: Write the retrosynthetic disconnection. Break the compound at the α,β-unsaturated bond to identify the two starting materials. The disconnection suggests that the compound can be formed by the reaction of cyclohexanone and acetone (CH3COCH3).

Step 4: Assess the feasibility of the aldol condensation. Cyclohexanone can form an enolate ion under basic conditions, and acetone can act as the electrophile. The reaction is feasible because both components are reactive under typical aldol condensation conditions.

Step 5: Summarize the reaction mechanism. Under basic conditions, cyclohexanone forms an enolate ion, which attacks the carbonyl carbon of acetone. This forms a β-hydroxyketone intermediate, which then undergoes dehydration to yield the α,β-unsaturated ketone product shown in the image.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

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. Understanding this process is crucial for dissecting compounds into their respective reagents.

Enolate Ion Formation

Enolate ions are formed when a base abstracts an alpha-hydrogen from a carbonyl compound, resulting in a resonance-stabilized anion. This ion acts as a nucleophile in aldol reactions, allowing it to attack another carbonyl carbon. Recognizing how enolate ions are generated and their role in aldol condensation is essential for analyzing the feasibility of the reaction.

Intramolecular Aldol Condensation

Intramolecular aldol condensation occurs when the aldehyde or ketone reacts with itself within the same molecule, forming a cyclic compound. This process is often favored due to the stability of the resulting ring structure. Identifying whether a compound can undergo intramolecular aldol condensation is key to determining the feasibility of the reaction presented in the question.

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Show how each compound can be dissected into reagents joined by an aldol condensation, then decide whether the necessary aldol condensation is feasible.(e)

Key Concepts

Aldol Condensation

Enolate Ion Formation

Intramolecular Aldol Condensation

Watch next

Show how each compound can be dissected into reagents joined by an aldol condensation, then decide whether the necessary aldol condensation is feasible.
(e)