Textbook Question
Predict the major product of the following electrophilic aromatic substitution reactions.
(b)
2
views
Ch. 23 - Benzene I: Aromatic Stability and Substitution Reactions
Mullins1st EditionOrganic Chemistry: A Learner Centered ApproachISBN: 9780137566471
Not the one you use?Change textbookSelect a different textbook
Table of contents
- Ch. 2 - General Chemistry Translated: Finding the Electrons114
- Ch. 3 - Alkanes and Cycloalkanes: Properties and Conformational Analysis109
- Ch. 4 - Acids and Bases: Electron Flow144
- Ch. 5 - Chemical Reaction Analysis: Thermodynamics and Kinetics118
- Ch. 6 - Stereoisomerism: Arrangement of Atoms in Space112
- Ch. 7 - Principles of Green (Organic) Chemistry3
- Ch. 8 - Alkenes I: Properties and Electrophilic Additions158
- Ch. 9 - Alkenes II: Oxidation and Reduction150
- Ch. 10 - Alkynes: Electrophilic Addition and Redox Reactions101
- Ch. 11 - Properties and Synthesis of Alkyl Halides: Radical Reactions108
- Ch. 12 - Substitution and Elimination: Reactions of Haloalkanes172
- Ch. 13 - Alcohols, Ethers and Related Compounds: Substitution and Elimination239
- Ch. 14 - Structural Identification I: Infrared Spectroscopy and Mass Spectrometry54
- Ch. 15 - Structural Identification II: Nuclear Magnetic Resonance Spectroscopy93
- Ch. 16 - Metals in Organic Chemistry48
- Ch. 17 - Carbonyl Addition Reactions: Aldehydes and Ketones45
- Ch. 18 - Nucleophilic Acyl Substitution I: Carboxylic Acids18
- Ch. 19 - Nucleophilic Acyl Substitution II: Carboxylic Acid Derivatives39
- Ch. 20 - Enolates: Carbonyl Addition and Substitution13
- Ch. 21 - Conjugated Systems I: Stability and Addition Reactions56
- Ch. 22 - Conjugated Systems II: Pericyclic Reactions54
- Ch. 23 - Benzene I: Aromatic Stability and Substitution Reactions64
- Ch. 24 - Benzene II: Reactions Influenced by the Aromatic Ring62
- Ch. 25 - Amines: Structure, Reactions, and Synthesis27
- Ch. 26 - Amino Acids, Proteins, and Peptide Synthesis9
- Ch. 27 - Carbohydrates, Nucleic Acids, and Lipids54
Mullins1st EditionOrganic Chemistry: A Learner Centered ApproachISBN: 9780137566471Not the one you use?Change textbook
All textbooks
Mullins 1st EditionCh. 23 - Benzene I: Aromatic Stability and Substitution ReactionsProblem 33b
Mullins 1st EditionCh. 23 - Benzene I: Aromatic Stability and Substitution ReactionsProblem 33bChapter 22, Problem 33b
Predict the product of the following Friedel–Crafts acylation reactions.
(b) 
Verified step by step guidance1
Identify the acyl chloride in the reaction. In this case, it is a 4-chlorobutanoyl chloride, which will be used in the Friedel-Crafts acylation.
Recognize the role of AlCl₃ as a Lewis acid catalyst. It will facilitate the generation of the acylium ion from the acyl chloride.
Understand that the acylium ion, which is a positively charged species, will be formed by the interaction of the acyl chloride with AlCl₃. This ion is highly electrophilic and will attack the benzene ring.
Predict the site of electrophilic attack on the benzene ring. The acylium ion will preferentially attack the para position relative to any existing substituents, unless steric hindrance or other directing effects are present.
Consider the final product structure. The acyl group will be added to the benzene ring, resulting in a ketone with the acyl group attached to the para position of the benzene ring.
Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Was this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Friedel-Crafts Acylation
Friedel-Crafts acylation is a reaction that introduces an acyl group into an aromatic ring using an acyl chloride and a Lewis acid catalyst, typically aluminum chloride (AlCl3). The reaction proceeds through the formation of an acylium ion, which acts as an electrophile, attacking the electron-rich aromatic ring to form a ketone. This reaction is useful for adding carbonyl groups to aromatic compounds, enhancing their reactivity and functional diversity.
Recommended video:
Guided course
05:20
Friedel-Crafts Acylation
Role of Aluminum Chloride (AlCl3)
Aluminum chloride (AlCl3) is a strong Lewis acid used as a catalyst in Friedel-Crafts reactions. It facilitates the generation of the acylium ion from the acyl chloride by accepting a chloride ion, thus increasing the electrophilicity of the acyl group. This enhanced electrophile can then effectively attack the aromatic ring, leading to the substitution of a hydrogen atom with the acyl group, forming a ketone.
Recommended video:
Guided course
03:13Acid Chloride Nomenclature
Electrophilic Aromatic Substitution
Electrophilic aromatic substitution (EAS) is a fundamental reaction mechanism in organic chemistry where an electrophile replaces a hydrogen atom on an aromatic ring. In the context of Friedel-Crafts acylation, the acylium ion acts as the electrophile, attacking the π-electron-rich benzene ring. The reaction proceeds through the formation of a resonance-stabilized carbocation intermediate, followed by deprotonation to restore aromaticity, resulting in the acylated aromatic compound.
Recommended video:
Guided course
03:07EAS Review
Related Practice
Textbook Question
The zwitterionic form of carbonyls is often used to explain their electrophilicity. Draw the zwitterionic structure of NO+2. Why is this such a great electrophile at the central nitrogen?
1
views
Textbook Question
Predict the product of the following Friedel–Crafts alkylation reactions. Assume only one alkyl group adds in each case.
(d)
1
views
Textbook Question
With a small electron-donating group on the ring, it is possible to get as much as a 2:1 ratio of ortho to para. Why might this be?
1
views
Textbook Question
In Section 23.7.4, we learned that Friedel–Crafts alkylation suffers from overalkylation.
(a) Draw the product of a Friedel–Crafts reaction that resulted in three methyl groups adding to the ring.
(b) Why is hard to stop at the addition of one alkyl group?
Textbook Question
Classify the following conjugated systems as having 4n or 4n + 2 π electrons.
(f)
1
views