The amino group is introduced into the aromatic ring by reduction of the nitro.

The reagents used in the reduction can be:

• Sn, HCl
• H₂ , Ni, EtOH
• Fe, HCl

Peracids oxidize the amino group to nitro.

Since the amino group orients to ortho/para and the nitro to meta, the conversion of one group to another is a method of important synthetic utility.