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

22. Carboxylic Acid Derivatives: NAS

Nucleophilic Acyl Substitution

Organic Chemistry

22. Carboxylic Acid Derivatives: NAS

Nucleophilic Acyl Substitution

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6:25 minutes

Problem 48g

Textbook Question

Show how you would accomplish the following syntheses in good yields.
(g)

Verified step by step guidance

Step 1: Analyze the starting material and the product. The starting material is a cyclic ketone with two ester groups (-COOCH₃) attached to the alpha-carbon. The product has the same cyclic ketone structure, but the ester groups have been converted into beta-keto esters (-CH₂COCH₃). This suggests a transformation involving enolate chemistry.

Step 2: Recognize that the transformation likely involves a Claisen condensation. In this reaction, an ester reacts with a base to form an enolate, which then undergoes nucleophilic attack on another ester molecule, forming a beta-keto ester.

Step 3: Choose an appropriate base for the reaction. A strong base such as sodium ethoxide (NaOEt) or sodium methoxide (NaOMe) is commonly used for Claisen condensations. The base will deprotonate the alpha-hydrogen of the ester group, forming the enolate intermediate.

Step 4: Ensure the reaction conditions are suitable for Claisen condensation. The reaction should be carried out in an alcohol solvent (e.g., ethanol or methanol) that matches the alkoxide base used. After the reaction, an acid workup (e.g., H₃O⁺) is typically performed to neutralize the base and isolate the product.

Step 5: Verify the product structure. The Claisen condensation will result in the formation of the desired beta-keto ester groups (-CH₂COCH₃) on the alpha-carbon of the cyclic ketone. This matches the target product shown in the problem.

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Key Concepts

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

Synthetic Pathways

Synthetic pathways refer to the series of chemical reactions and transformations that convert starting materials into desired products. Understanding these pathways is crucial for planning a synthesis, as it involves selecting appropriate reagents, conditions, and reaction mechanisms to achieve high yields and purity of the target compound.

Reaction Mechanisms

Reaction mechanisms describe the step-by-step process by which reactants are converted into products, detailing the bond-breaking and bond-forming events. A solid grasp of mechanisms helps predict the outcomes of reactions, optimize conditions, and troubleshoot potential issues that may arise during synthesis.

Yield Optimization

Yield optimization involves strategies to maximize the amount of desired product obtained from a reaction. This includes adjusting reaction conditions such as temperature, concentration, and time, as well as employing techniques like purification and recycling of reagents to enhance overall efficiency and minimize waste.

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