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

19. Reactions of Aromatics: EAS and Beyond

Nucleophilic Aromatic Substitution

Organic Chemistry

19. Reactions of Aromatics: EAS and Beyond

Nucleophilic Aromatic Substitution

Previous problemNext problem

5:54 minutes

Problem 95

Textbook Question

Propose a mechanism for each of the following reactions:
b.

Verified step by step guidance

Step 1: Analyze the reactants and products. The starting material contains a hydroxyl group (-OH) and a sulfone group (-SO2) attached to a benzene ring. The product shows the formation of an ether bond (-O-) between two aromatic rings, with the sulfone group now bearing a negative charge.

Step 2: Recognize the role of the reagent, NaOCH3. Sodium methoxide (NaOCH3) is a strong base and can deprotonate the hydroxyl group (-OH) on the benzene ring, forming a phenoxide ion (-O⁻). This phenoxide ion is highly nucleophilic.

Step 3: Propose the nucleophilic attack mechanism. The phenoxide ion generated in Step 2 can attack the electrophilic sulfone group (-SO2) on the adjacent benzene ring. This results in the formation of a new ether bond (-O-) between the two aromatic rings.

Step 4: Account for the charge distribution. After the nucleophilic attack, the sulfone group (-SO2) loses one of its oxygen atoms to form a negatively charged sulfonate group (-SO2⁻). This charge is stabilized by resonance within the sulfonate group.

Step 5: Verify the mechanism consistency. Ensure that the proposed mechanism aligns with the observed product structure, including the ether bond formation and the sulfonate group (-SO2⁻) in the final 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.

Williamson Ether Synthesis

Williamson Ether Synthesis is a method for producing ethers through the reaction of an alkoxide ion with a primary alkyl halide. In this reaction, the alkoxide acts as a nucleophile, attacking the electrophilic carbon of the alkyl halide, leading to the formation of an ether. This reaction is particularly effective with primary halides to avoid elimination reactions.

Nucleophilic Substitution Mechanism

Nucleophilic substitution is a fundamental reaction mechanism in organic chemistry where a nucleophile replaces a leaving group in a molecule. This can occur via two main pathways: SN1, which involves a two-step mechanism with a carbocation intermediate, and SN2, which is a one-step process where the nucleophile attacks the substrate simultaneously as the leaving group departs. The choice of mechanism depends on the structure of the substrate and the conditions of the reaction.

Alkoxide Ion

An alkoxide ion is a deprotonated alcohol, represented as R-O⁻, where R is an alkyl group. Alkoxides are strong nucleophiles and are commonly used in organic synthesis, particularly in reactions like Williamson Ether Synthesis. They can be generated by treating alcohols with strong bases, such as sodium hydride or sodium metal, making them highly reactive in forming new carbon-oxygen bonds.

Watch next

Master General Mechanism with a bite sized video explanation from Johnny

Start learning

Related Videos

Related Practice

Textbook Question

Show how the substituents containing the azo group (N=N) can facilitate both electrophilic and nucleophilic aromatic substitution.

(b)

Textbook Question

Show how you would accomplish the following syntheses.

Textbook Question

Explain why hydroxide ion catalyzes the reaction of piperidine with 2,4-dinitroanisole but has no effect on the reaction of piperidine with 1-chloro-2,4-dinitrobenzene.

Textbook Question

Rank the following compounds from greatest tendency to least tendency to undergo nucleophilic aromatic substitution:

chlorobenzene

1-chloro-2,4-dinitrobenzene

p-chloronitrobenzene

Multiple Choice

Provide the structure of the product formed from the reaction of 1-bromo-2,4,6- trinitrobenzene with one equivalent of sodium methoxide.

Multiple Choice

Provide the major organic product for the following reaction.

Multiple Choice

Provide the major organic product for the following reaction.

Multiple Choice