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

Previous problemNext problem

2:34 minutes

Problem 75

Textbook Question

An aqueous solution of a primary or secondary amine reacts with an acyl chloride to form an amide as the major product. However, if the amine is tertiary, an amide is not formed. What product is formed? Explain.

Verified step by step guidance

Understand the reactivity of amines: Primary and secondary amines have a hydrogen atom attached to the nitrogen, which allows them to act as nucleophiles and react with acyl chlorides to form amides. Tertiary amines, however, lack this hydrogen atom, which makes them unable to form amides in this reaction.

Analyze the reaction mechanism: In the case of primary or secondary amines, the lone pair of electrons on the nitrogen attacks the carbonyl carbon of the acyl chloride, leading to the formation of a tetrahedral intermediate. This intermediate then eliminates HCl to form the amide product.

Consider the case of tertiary amines: Since tertiary amines do not have a hydrogen atom on the nitrogen, they cannot eliminate HCl to form an amide. Instead, they act as bases and react with the HCl produced during the reaction.

Predict the product: When a tertiary amine reacts with an acyl chloride, the tertiary amine typically forms a salt by accepting a proton from the HCl. The product is an ammonium salt, specifically a quaternary ammonium chloride.

Summarize the outcome: For primary and secondary amines, the major product is an amide. For tertiary amines, the reaction does not produce an amide but instead forms a quaternary ammonium salt as the major product.

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.

Amine Reactivity

Amines are organic compounds derived from ammonia by replacing one or more hydrogen atoms with alkyl or aryl groups. Primary and secondary amines have at least one hydrogen atom available for nucleophilic attack, allowing them to react with acyl chlorides to form amides. In contrast, tertiary amines lack this hydrogen, making them unable to form amides through this reaction.

Acyl Chloride

Acyl chlorides, also known as acid chlorides, are reactive compounds containing a carbonyl group (C=O) bonded to a chlorine atom. They are highly electrophilic and readily react with nucleophiles, such as amines, to form amides. The reaction involves the nucleophilic attack of the amine on the carbonyl carbon, leading to the formation of the amide and the release of hydrochloric acid.

Amide Formation

Amides are organic compounds characterized by the presence of a carbonyl group (C=O) directly attached to a nitrogen atom (N). The formation of amides from amines and acyl chlorides is a key reaction in organic chemistry, typically resulting in the substitution of the chlorine atom by the amine. This reaction is significant in synthesizing various pharmaceuticals and agrochemicals, highlighting the importance of understanding the reactivity of different amine types.

Watch next

Master NAS - The Three Rules with a bite sized video explanation from Johnny

Start learning