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

13. Alcohols and Carbonyl Compounds

Organometallic Cumulative Practice

Organic Chemistry

13. Alcohols and Carbonyl Compounds

Organometallic Cumulative Practice

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6:20 minutes

Problem 29c

Textbook Question

Show how you would accomplish the following syntheses. You may use whatever additional reagents you need.
(c)

Verified step by step guidance

Step 1: Analyze the starting material and the product. The starting material is a bromomethyl ketone, and the product is an α,β-unsaturated ketone with a phenyl group attached to the β-carbon. This suggests that the reaction involves a substitution followed by elimination.

Step 2: Perform a nucleophilic substitution reaction. Use a phenyl nucleophile, such as a phenyl Grignard reagent (PhMgBr) or phenyl lithium (PhLi), to replace the bromine atom with a phenyl group. This step generates an intermediate with a phenyl group attached to the α-carbon.

Step 3: Introduce conditions for elimination. Use a base, such as potassium tert-butoxide (KOtBu) or sodium hydride (NaH), to promote the elimination of a proton from the α-carbon and the formation of a double bond between the α- and β-carbons. This step results in the formation of the α,β-unsaturated ketone.

Step 4: Ensure stereochemistry and regioselectivity. Verify that the elimination occurs in the correct position to yield the desired conjugated system with the phenyl group attached to the β-carbon.

Step 5: Purify the product. Use techniques such as distillation or chromatography to isolate the α,β-unsaturated ketone with the phenyl group attached to the β-carbon.

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Key Concepts

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

Nucleophilic Substitution

Nucleophilic substitution is a fundamental reaction in organic chemistry where a nucleophile attacks an electrophilic carbon atom, replacing a leaving group. In this synthesis, the bromine atom in CH2Br acts as a leaving group, allowing the nucleophile to form a new bond with the carbon atom. Understanding this mechanism is crucial for predicting the outcome of the reaction.

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, which can further dehydrate to form α,β-unsaturated carbonyl compounds. This process is essential in the synthesis shown, as it allows for the formation of the desired product through the coupling of two carbonyl compounds.

Electrophilic Aromatic Substitution

Electrophilic aromatic substitution is a reaction where an electrophile replaces a hydrogen atom on an aromatic ring. In the context of the provided synthesis, the phenyl group (Ph) can be introduced to the aromatic compound through this mechanism, allowing for the formation of the final product. Recognizing the role of aromaticity and the stability of the intermediates is key to understanding this step.

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Textbook Question

Show how each of the following compounds can be prepared, using the given starting material:

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Identify A through O:

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a. Show the reagents required to form the primary alcohol in each of the following reactions.

Textbook Question

a. Show the reagents required to form the primary alcohol in each of the following reactions.

Textbook Question

Predict the major products of the following reactions.

(d)

Textbook Question

Two of the methods for converting alkyl halides to carboxylic acids are covered in Sections 20-8B and 20-8C. One is formation of a Grignard reagent followed by addition of carbon dioxide and then dilute acid. The other is substitution by cyanide ion, followed by hydrolysis of the resulting nitrile. For each of the following conversions, decide whether either or both of these methods would work, and explain why. Show the reactions you would use.

(a)

(b)

Textbook Question

Predict the products of the following reactions.

(a) sec-butylmagnesium iodide + D₂O

(b) n-butyllithium + CH₃CH₂OH

Textbook Question

Point out the flaws in the following incorrect Grignard syntheses.

(a)

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