Quiz - Electrophilic Aromatic Substitution - 3 | Electrophilic Aromatic Substitution

Organic Chemistry 2 - Quiz - Electrophilic Aromatic Substitution - 3


What is the role of FeBr3 in the bromination of benzene?

FeBr3 acts as a Lewis acid to coordinate with bromine, creating a Br+ cation that is a strong electrophile capable of attacking the electron-rich benzene ring, facilitating its bromination.


During nitration of benzene, what is the electrophile that reacts with the benzene ring?

The nitronium ion (NO2+), generated from the reaction between nitric acid (HNO3) and sulfuric acid (H2SO4), is the true electrophile in the nitration of benzene.


What functional group is introduced during the sulfonation of benzene?

The sulfonation of benzene introduces a sulfonic acid group (-SO3H) onto the benzene ring, as benzene reacts with sulfur trioxide (SO3) in sulfuric acid.


Friedel-Crafts Alkylation can result in polysubstitution because alkyl groups are:

Alkyl groups are ortho/para-directing and activating due to their electron-donating inductive effect, which increases the electron density of the benzene ring and can lead to polysubstitution.


In Friedel-Crafts Acylation, the electrophile is a(n):

The electrophile in a Friedel-Crafts Acylation reaction is an acylium ion, which is generated from the acyl halide in the presence of a Lewis acid catalyst.


Which effect explains why electron-donating groups facilitate EAS more than electron-withdrawing groups?

Electron-donating groups facilitate EAS more than electron-withdrawing groups due to both inductive and resonance effects, which increase the electron density on the benzene ring, making it more reactive towards electrophiles.


Why is EAS of disubstituted benzene less straightforward than monosubstituted benzene?

EAS of disubstituted benzene is complicated by the fact that each substituent can have its own directing effects, which could be either additive or opposing, affecting the outcome of the reaction.


Which synthesis strategy is commonly employed for the generation of electrophiles used in EAS?

The use of Lewis acids to generate electrophilic species from reagents like acyl halides or alkyl halides is a common strategy in EAS to create the strong electrophiles necessary for reaction with benzene.