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

26. Amines

Amines by Reduction

Organic Chemistry

26. Amines

Amines by Reduction

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2:04 minutes

Problem 30a

Textbook Question

Show how you would accomplish the following synthetic conversions.
(a) benzyl bromide → benzylamine

Verified step by step guidance

Identify the functional group transformation: The conversion involves replacing the bromine atom in benzyl bromide with an amine group (-NH2), which is a nucleophilic substitution reaction.

Choose an appropriate nucleophile: Ammonia (NH3) is a good nucleophile for this reaction, as it can replace the bromine atom to form benzylamine.

Select the reaction conditions: Use an excess of ammonia in a polar solvent like ethanol to promote the substitution reaction. This ensures that the nucleophilic substitution proceeds efficiently.

Write the reaction mechanism: The reaction proceeds via an SN2 mechanism, where the nucleophile (NH3) attacks the carbon atom bonded to the bromine, displacing the bromine atom as a leaving group. The reaction can be represented as:

C_{6} H_{5} CH Br + NH ₃ \to C_{6} H_{5} CH NH ₂ + HBr

Isolate and purify the product: After the reaction is complete, the benzylamine product can be separated from the reaction mixture by techniques such as extraction, followed by purification using distillation or recrystallization.

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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 electrophile, resulting in the replacement of a leaving group. In the conversion of benzyl bromide to benzylamine, the bromine atom acts as the leaving group, while the amine (NH2) serves as the nucleophile. Understanding this mechanism is crucial for predicting the outcome of the reaction.

Reactivity of Alkyl Halides

Alkyl halides, such as benzyl bromide, are compounds where a halogen atom is bonded to an alkyl group. The reactivity of these compounds is influenced by the nature of the halogen and the structure of the alkyl group. Benzyl bromide is particularly reactive due to the stability of the resulting carbocation during the nucleophilic substitution process, making it a suitable substrate for conversion to benzylamine.

Amine Nucleophilicity

Amines are organic compounds that contain a nitrogen atom bonded to hydrogen and/or carbon atoms. They are known for their nucleophilic properties, meaning they can donate a pair of electrons to form a bond with an electrophile. In the context of synthesizing benzylamine from benzyl bromide, the amine's nucleophilicity is essential for effectively attacking the electrophilic carbon in the alkyl halide, facilitating the substitution reaction.

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Textbook Question

Show how each transformation may be accomplished by using a nitrile as an intermediate. You may use any necessary reagents.

(a) hexan-1-ol → heptan-1-amine

Textbook Question

Show how to prepare the following aromatic amines by aromatic nitration, followed by reduction. You may use benzene and toluene as your aromatic starting materials.

(d) m-aminobenzoic acid

Textbook Question

Show how you can synthesize the following compounds starting with benzene, toluene, and alcohols containing no more than four carbon atoms as your organic starting materials. Assume that para is the major product (and separable from ortho) in ortho, para mixtures.

(g) 4-isobutylaniline

Textbook Question

Using any necessary reagents, show how you can accomplish the following multistep syntheses.

(b)

Textbook Question

Several additional amine syntheses are effectively limited to making primary amines. The reduction of azides and nitro compounds and the Gabriel synthesis leave the carbon chain unchanged. Formation and reduction of a nitrile adds one carbon atom. Show how these amine syntheses can be used for the following conversions.

Textbook Question

Starting with cyclohexene, how can the following compounds be prepared?

b. cyclohexylmethylamine

Textbook Question

How could you convert N-methylbenzamide to the following compounds?

a. N-methylbenzylamine

Textbook Question

What are the products of the following reactions?

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