Synthetic routes to an aromatic amine:

As a second instance, let us consider the synthesis of an aromatic amine. The alkylamine group cannot be applied to an aromatic ring straight and thus must be acquired by changing other functional group. Working backwards, the alkylamine group could be acquired through alkylation of an amino group (NH₂). An amino group cannot be straight applied to an aromatic ring either. Though, an amino group could be acquired by reduction of a nitro group. A nitro group can be applied straight to an aromatic ring. So, the complete synthesis would be nitration followed through reduction and alkylation.

Note: There are two techniques of converting aniline (PhNH₂) to the last product. Alkylation is the direct method, but occasionally acylation followed through reduction provides better yields, despite the extra step. This is since it is sometimes hard to control the alkylation to just one alkyl group.

Figure: Possible synthetic routes to an aromatic amine.