Question

Draw a stepwise mechanism for the following reaction.

Short answer

The name, electrophilic substitution, comes from the electrophile which is placed on the substrate (electron-rich). Therefore, the carbocations are also substituted as the electrophiles.

Step-by-step solution

Electrophilic substitution reaction

The name, electrophilic substitution, comes from the electrophile which is placed on the substrate (electron-rich). Therefore, the carbocations are also substituted as the electrophiles.

Generation of electrophile

Electrophiles are generated in the presence of Lewis acid. The Lewis acid accepts the anion (from the substrate) and completes its octet.

Electrophilic substitution and the abstraction of hydrogen

Electrophiles are substituted in the second step on the substrate. The third step involves the abstraction of hydrogen from the base which forms the final product.

Explanation

The stepwise mechanism for the given question is shown as: