Question

Why is heterocyclic chemistry such a vast field?

Answer 1

Consider the wealth of organic compounds with ONLY carbon and hydrogen atoms.......

Explanation:

Add in a nitrogen heteroatom, and we add another layer onto the chemistry, i.e. we go from `C_nH_(2n+2)` to `C_nH_(2n+1)N`, the same thing will occur with oxygen, sulfur, etc. There is a whole army of chemists who deal with heterocyclic chemistry.......pyrroles, furans, thiophenes, etc....... The heteroatom adds vast possibilities for structure and chemistry; the presence of lone pairs on the nitrogen or oxygen centre gives so-called `pi-"excessive"` molecules that ARE MORE reactive than benzene.