What is the Difference Between Electrophilic and Nucleophilic Substitution?

The main difference between electrophilic and nucleophilic substitution lies in the reactants involved and the nature of the substitution reaction. Here are the key differences:

1. Electrophilic Substitution:

• Involves the substitution of a hydrogen atom in an aromatic ring by an electrophile, which is a species that accepts electrons.
• The electrophile attacks the aromatic ring, forming a carbocation intermediate.
• This type of substitution reaction typically results in the retention of the absolute configuration.

1. Nucleophilic Substitution:

• Involves the substitution of a leaving group in an aromatic ring by a nucleophile, which is a species that donates electrons.
• The nucleophile attacks the aromatic ring, displacing the leaving group.
• There are two types of nucleophilic substitution reactions: ${{S}{N}}^{1}$ and ${{S}{N}}^{2}$, which take place in one and two steps, respectively. The ${{S}_{N}}^{2}$ reaction follows the inversion of configuration.

In summary, electrophilic substitution involves the replacement of a hydrogen atom by an electrophile, while nucleophilic substitution involves the replacement of a leaving group by a nucleophile. The reactants, mechanism, and configuration changes differ between the two types of substitution reactions.

Comparative Table: Electrophilic vs Nucleophilic Substitution

Here is a table comparing the differences between electrophilic and nucleophilic substitution:

In summary, electrophilic substitution occurs when an electrophile (a positively charged or partially positive species) attacks a molecule, while nucleophilic substitution occurs when a nucleophile (a molecule rich in electrons) attacks a molecule. Electrophilesaccept electron pairs, while nucleophiles donate electron pairs. These differences in reactivity and stereochemistry can be useful in understanding and predicting the outcomes of various reactions in organic and inorganic chemistry.