Amines Part 1

In first step, ${\mathit{N}\mathit{O}}_2$ group is electron withdrawing group, it decreases the electron density in meta position and bromination occur in meta position. In second step, $\mathit{S}\mathit{n}∕\mathit{H}\mathit{C}\mathit{l}$ used for reduction to convert $-{\mathit{N}\mathit{O}}_2$ to $-{\mathit{N}\mathit{H}}_2$ and form aniline. In next step, diazonium salt is formed and at last bromine replace ${\mathit{N}}_2^{+}{\mathit{C}\mathit{l}}^{-}$group to form 1 , 3-dibromobenzene.
Complete reaction is as follows