Question

Convert (i) 3-Methylaniline into 3-nitrotoluene.

Answer 1

Hint:
The structures of 3-Methylaniline and 3-nitrotoluene are shown below.

From the structures if given names, it is clear that the amine group is changed into nitro group. So, you have to do such reactions where an amine group can change into a nitro group with unchanged another group in the compound.

Complete step by step answer:
There are so many different kinds of reaction sequence pathways to do this conversion. One of those is using diazonium cation formation reaction as one reaction of the sequence. This diazonium formation is a very common reaction from class XII organic chemistry.
Now the diazonium formation reaction is shown below,

From the diazonium cation nitrobenzene can be produced very easily. To convert diazonium cation nitro benzene the following process can be used.

Now using these two reactions the conversion of 3-Methylaniline to 3-nitrotoluene is possible as follows.
Additional information:
There are so many other conversions also possible from diazonium cation. For example, chlorobenzene formation, cyano benzene formation, aniline formation etc. these reactions are shown below,

Note:
Aliphatic amines form diazonium salt which is unstable as it is not resonance stabilized and hence gives nitrogen and carbonium ions.