The compounds X, Y and Z are as shown.
X=C6H5NH2
Y=C6H5N2Cl
Z=C6H5NO2
The reaction is as shown:
C6H5CONH2Br2→KOHC6H5NH2XHNO2→HClC6H5N2ClYNaNO2→Cu+C6H5NO2Z
Hoffmann bromamide degradation of benzamide gives aniline. Aniline is diazotized to form benzene diazonium chloride. The diazonium salt s then converted into nitrobenzene by treatment with NaNO2/Cu+