Electrophilic Aromatic Substitution

We have learned that activating groups are ortho, para directors, and the meta product for these benzene derivatives is obtained only in negligible quantities. To obtain a meta-substitution product, a deactivating group such as a nitro or a carbonyl group is needed. … Read more

Preparation of Aniline There are a few main ways of preparing aniline: Reduction of the Nitro Group We can add a nitro group to benzene or its derivative via a standard nitration using HNO3 and H2SO4, and then reduce the … Read more

Preparation of Phenols Phenols can be prepared industrially by a substitution reaction of aryl halides under extreme conditions:     This is a type of nucleophilic aromatic substitution via a benzyne intermediate:     Milder conditions suitable for laboratory preparation … Read more

In the last few articles, we talked about the key electrophilic aromatic substitution reactions and the synthetic strategies based on the ortho, meta, para directing effects.    Below is a summary of electrophilic aromatic substitution practice problems from different topics. … Read more

In the previous post, we talked about the nucleophilic aromatic substitution, looking at the specifics of the mechanism, regiochemistry, and the limitations.  Below are some additional examples to practice these concepts.    

We have seen that most reactions of aromatic compounds involve electrophilic substitutions because the π electrons make the aromatic ring electron-rich and therefore, nucleophilic. However, some aryl halides with a strong electron-withdrawing substituent(s) on the ring can undergo nucleophilic substitution … Read more

The benzylic position is quite reactive and presents a useful synthetic tool for preparing many aromatic compounds. The reason for this reactivity is the resonance stabilization of the benzylic carbon, regardless of whether the reaction goes through an ionic or … Read more

We have already talked about the ortho, para, and meta directions in electrophilic aromatic substitution and their combined effect for disubstituted benzene. This should allow us to synthesize different aromatic compounds starting from benzene. For example, how can we synthesize … Read more

In the previous post, we saw that a benzene ring with an activator undergoes electrophilic aromatic substitution at the ortho and para positions, while deactivated aromatic rings react at the meta position:     Here is an interesting question: Where … Read more