Question

What are the electrophile and nucleophilic in the electrophilic aromatic substitution reaction.

Answer 1

Electrophile is an atom or functional group who reacts with aromatic organic compound in which a hydrogen atom or any other aromatic functional group of an organic compound is get attached with electrophile.

Total 6 type of electrophiles can be seen as follows:-

1.Chlorination

2.Bromination

3.Nitration

4.Sulphonylation

5.Alkylation

6.Acylation

1.In chlorination, Cl atom acts as an electrophile and any chlorine salt like FeCl3 or AlCl3 can act as nucleophile. Here, Nucleophile is lewis acid which is AlCl3 or FeCl3 which accepts a lone pair of electron to make Cl2 much better nucleophile. Then this nucleophile reacts with organic compound to form chloride organic compound.

2. In bromination, same as chlorination, Br2 is electrophile and AlBr3 or FeBr3 can be nucleophile.

3. Nitration is carried out by nitric acid in which NO2 group acts as electrophile while an acid like H2SO4 can act as nucleophile.

4. Sulfonylation is carried out with Sulphur trioxide as electrophile while again H2SO4 can be a nucleophile.

5.Alkylation is reaction of aromatic organic compound with alkyl halide mostly, alkyl group gets added into organic compound so alkyl group is electrophile and AlCl3 or FeCl3 can be nucleophile.

6.Acylation is addition of "RCO" group works as electrophile and AlCl3 acts as nucleophile.