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

reduction nitro to amino

The reagents used in the reduction can be:

  • Sn, HCl
  • H2 , Ni, EtOH
  • Fe, HCl

Peracids oxidize the amino group to nitro.

amino oxidation 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.