Chapter 18
Reactions of Aromatic Compounds
![NMR Spectroscopy of Benzene Derivatives](https://cloudfront.jove.com/files/media/science-education/science-education-thumbs/12871.jpg)
Simple unsubstituted benzene has six aromatic protons, all chemically equivalent. Therefore, benzene exhibits only a singlet peak at δ 7.3…
![Reactions at the Benzylic Position: Oxidation and Reduction](https://cloudfront.jove.com/files/media/science-education/science-education-thumbs/12463.jpg)
The benzylic position describes the position of a carbon atom attached directly to a benzene ring. Benzene by itself does not undergo oxidation. In…
![Electrophilic Aromatic Substitution: Overview](https://cloudfront.jove.com/files/media/science-education/science-education-thumbs/12464.jpg)
In an electrophilic aromatic substitution reaction, an electrophile substitutes for a hydrogen of an aromatic compound.
Many functional groups can…
![Electrophilic Aromatic Substitution: Chlorination and Bromination of Benzene](https://cloudfront.jove.com/files/media/science-education/science-education-thumbs/12874.jpg)
Chlorination and bromination are important classes of electrophilic aromatic substitutions, where benzene reacts with chlorine or bromine in the…
![Electrophilic Aromatic Substitution: Nitration of Benzene](https://cloudfront.jove.com/files/media/science-education/science-education-thumbs/12465.jpg)
The nitration of benzene is an example of an electrophilic aromatic substitution reaction. It involves the formation of a very powerful electrophile,…
![Electrophilic Aromatic Substitution: Sulfonation of Benzene](https://cloudfront.jove.com/files/media/science-education/science-education-thumbs/12466.jpg)
Sulfonation of benzene is a reaction wherein benzene is treated with fuming sulfuric acid at room temperature to produce benzenesulfonic acid. Fuming…
![Electrophilic Aromatic Substitution: Friedel–Crafts Acylation of Benzene](https://cloudfront.jove.com/files/media/science-education/science-education-thumbs/12468.jpg)
The Friedel–Crafts acylation reactions involve the addition of an acyl group to an aromatic ring. These reactions proceed via electrophilic…
![Limitations of Friedel–Crafts Reactions](https://cloudfront.jove.com/files/media/science-education/science-education-thumbs/12469.jpg)
Several restrictions limit the use of Friedel–Crafts reactions. First, the halogen in the alkyl halide must be attached to an sp3-hybridized…
![Directing Effect of Substituents: <em>meta</em>-Directing Groups](https://cloudfront.jove.com/files/media/science-education/science-education-thumbs/12471.jpg)
Substituents on the benzene ring that direct an incoming electrophile to undergo substitution at the meta position are…
![<em>ortho</em>–<em>para</em>-Directing Activators: –CH<sub>3</sub>, –OH, –⁠NH<sub>2</sub>, –OCH<sub>3</sub>](https://cloudfront.jove.com/files/media/science-education/science-education-thumbs/12472.jpg)
All ortho–para directors, excluding halogens, are activating groups. These groups donate electrons to the ring, making the ring carbons…
![<em>meta</em>-Directing Deactivators: –NO<sub>2</sub>, –CN, –CHO, –⁠CO<sub>2</sub>R, –COR, –CO<sub>2</sub>H](https://cloudfront.jove.com/files/media/science-education/science-education-thumbs/12474.jpg)
All meta-directing substituents are deactivating groups. These substituents withdraw electrons from the aromatic ring, making the ring less reactive…
![Directing and Steric Effects in Disubstituted Benzene Derivatives](https://cloudfront.jove.com/files/media/science-education/science-education-thumbs/12475.jpg)
When disubstituted benzenes undergo electrophilic substitution, the product distribution depends on the directing effect of both substituents. When…
![Nucleophilic Aromatic Substitution: Elimination–Addition](https://cloudfront.jove.com/files/media/science-education/science-education-thumbs/12478.jpg)
Simple aryl halides do not react with nucleophiles. However, nucleophilic aromatic substitutions can be forced under certain conditions,…
![Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic S<sub>N</sub>1](https://cloudfront.jove.com/files/media/science-education/science-education-thumbs/12479.jpg)
Treating arylamines with nitrous acid gives aryldiazonium salts that are effective substrates in nucleophilic aromatic substitution reactions. The…
![Benzene to 1,4-Cyclohexadiene: Birch Reduction Mechanism](https://cloudfront.jove.com/files/media/science-education/science-education-thumbs/12481.jpg)
Birch reduction uses solvated electrons as reducing agents. The reaction converts benzene to 1,4-cyclohexadiene. The reaction proceeds by the…
![Hydrolysis of Chlorobenzene to Phenol: Dow Process](https://cloudfront.jove.com/files/media/science-education/science-education-thumbs/12482.jpg)
Simple aryl halides do not react with nucleophiles under normal conditions. However, the reaction can proceed under drastic conditions involving high…
![Efficient Synthesis of Polyfunctionalized Benzenes in Water <em>via</em> Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes](https://cloudfront.jove.com/files/thumbs/60767_t.png)
Benzannulation reactions represent an effective protocol to transform acyclic building blocks into structurally varied benzene skeletons. Despite…
![1,3,5-Triphenylbenzene and Corannulene as Electron Receptors for Lithium Solvated Electron Solutions](https://cloudfront.jove.com/files/thumbs/54366_t.png)
1,3,5-Triphenylbenzene and Corannulene as Electron Receptors for Lithium Solvated Electron Solutions
The authors report on conductivity studies carried out on lithium solvated electron solutions (LiSES) prepared using two types of polyaromatic…