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

Claisen Condensation

Organic Chemistry

25. Condensation Chemistry

Claisen Condensation

Previous problemNext problem

3:13 minutes

Problem 49a

Textbook Question

Draw the products of the following reactions:
a. diethyl heptanedioate: (1) sodium ethoxide; (2) HCl

Verified step by step guidance

Step 1: Analyze the structure of diethyl heptanedioate. It contains two ester groups (-COOEt) attached to a heptane backbone. The reaction involves two steps: (1) treatment with sodium ethoxide (CH3O⁻), a strong base, and (2) acidification with HCl.

Step 2: In the first step, sodium ethoxide acts as a base and deprotonates the alpha-hydrogen (hydrogen adjacent to the ester group). This generates an enolate ion, which is stabilized by resonance between the alpha-carbon and the carbonyl group.

Step 3: The enolate ion undergoes intramolecular nucleophilic attack on the second ester group, leading to the formation of a cyclic intermediate. This step is a key part of the Dieckmann condensation reaction, which forms a β-keto ester.

Step 4: In the second step, the reaction mixture is acidified with HCl. This protonates the intermediate and stabilizes the β-keto ester product. Additionally, any remaining ethoxide ions are neutralized.

Step 5: The final product is a cyclic β-keto ester, which is formed as a result of the Dieckmann condensation. The exact structure depends on the specific positions of the ester groups in the starting material.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above

Video duration:

Play a video:

Was this helpful?

Key Concepts

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

Claisen Condensation

Claisen condensation is a reaction between two esters or an ester and a carbonyl compound in the presence of a strong base, leading to the formation of a β-keto ester or a β-diketone. In this process, the base deprotonates the alpha hydrogen of one ester, allowing it to act as a nucleophile and attack the carbonyl carbon of another ester, resulting in a new carbon-carbon bond.

Sodium Ethoxide as a Base

Sodium ethoxide (NaOEt) is a strong base commonly used in organic synthesis, particularly in reactions like the Claisen condensation. It effectively deprotonates the alpha hydrogen of esters, generating an enolate ion that can participate in nucleophilic attacks on carbonyl compounds, facilitating the formation of larger carbon skeletons.

Acid Workup

An acid workup, typically involving a reagent like HCl, is performed after a reaction to protonate any negatively charged species formed during the reaction. In the context of Claisen condensation, the acid workup neutralizes the base and helps to stabilize the product by converting the enolate back to a carbonyl compound, ensuring the final product is in its desired form.

Watch next

Master Claisen Condensation with a bite sized video explanation from Johnny

Start learning

Draw the products of the following reactions: a. diethyl heptanedioate: (1) sodium ethoxide; (2) HCl

Key Concepts

Claisen Condensation

Sodium Ethoxide as a Base

Acid Workup

Watch next

Draw the products of the following reactions:
a. diethyl heptanedioate: (1) sodium ethoxide; (2) HCl