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

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Multiple Choice

Give the structure of the ester precursor for the following Claisen condensation product.

Reaction showing the Claisen condensation of two ester precursors.

Another representation of the Claisen condensation reaction with ester precursors.

Alternative view of the Claisen condensation reaction with ester precursors.

Final representation of the Claisen condensation reaction with ester precursors.

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Verified step by step guidance

Identify the Claisen condensation product structure. The product shown is an ester with a β-keto group, indicating it is formed from two ester molecules.

Recognize that in a Claisen condensation, two ester molecules react to form a β-keto ester. The reaction involves the formation of a new carbon-carbon bond between the α-carbon of one ester and the carbonyl carbon of another.

Analyze the product structure to determine the two ester precursors. The product has a phenyl group and an ethyl ester group, suggesting one precursor is ethyl benzoate.

Consider the second ester precursor. The product has an additional ethyl ester group and a methyl group adjacent to the carbonyl, indicating the second precursor is ethyl acetate.

Verify the precursors by mentally reconstructing the Claisen condensation reaction: ethyl benzoate and ethyl acetate react, with the enolate ion of ethyl acetate attacking the carbonyl carbon of ethyl benzoate, forming the observed β-keto ester product.