Question

What is the mechanism of aromatization?

Answer 1

Hint:Aromatization is a chemical reaction during which a single non-aromatic precursor is used to form an aromatic system.
An aromatic compound is the one which is planer, cyclic, has conjugation, and has (4n+2) pi electrons i.e., obeys Huckel’s rule.
There are many pathways for aromatization but the most common one is dehydrogenation.
Complete step by step answer:
Aromatization can be done using various pathways, some of them are described below:
Dehydrogenation of cyclic compounds:
E.g. dehydrogenation of cyclohexane in the presence of Platinum and heat will yield benzene.
  

Similarly, cyclohex-1-ene, cyclohex-1,4-diene will also give benzene as a product. As the degree of unsaturation of the precursor (reactant) increases the rate of the reaction also increases.
From Acyclic precursor:
Benzene can also be formed when 3 molecules of ethyne are heated at high temperatures in the presence of Zn dust which acts as a catalyst.
There are many more pathways to carry out aromatization but dehydrogenation remains the most widely used. Dehydrogenation, as the name suggests, is the removal of hydrogen from a molecule.
Aromatization also happens inside the biological system in various biological compounds. The difference is in a biological system the catalysts for the reaction are enzymes. The enzyme responsible for the aromatization of biologically active compounds is known as Aromatase.

Note: Aromatic compounds are called so because each aromatic compound has a distinct aroma (odour). They are known for their high stability and undergo any chemical change under drastic conditions. These are highly conjugated systems and undergo resonance.