26. Amines question bank (Chemistry)

Aniline on treatment with $NaNO_2 / HCl$ at about $0^\circ C$ gives a compound $A$, which on further treatment with $CuCN / KCN$ gives a compound $B$, which when reacts with $H_2 / Ni$ gives a compound $C$. The compound $C$ on reaction with $HNO_2$ gives a compound $D$. The structure of $D$ is:

The amine which reacts with $p$-toluene sulphonyl chloride to give a clear solution which on acidification gives an insoluble compound is: