Final answer:
Nitration of aniline leads to formation of ortho, meta, and para derivatives due to the amino group getting protonated under acidic conditions used for nitration, which causes it to direct the incoming nitro group to the meta position as well.
Step-by-step explanation:
Although aniline has an amino (NH₂) group, which is generally an ortho- and para-directing group in electrophilic aromatic substitution reactions, nitration of aniline also produces a significant amount of the meta-substituted product. This is due to the fact that under the acidic conditions employed for nitration, the amine group gets protonated, becoming an -NH₃⁺+, which is a meta-directing group. So, alongside the expected ortho and para nitro derivatives, you also get the meta derivative.
A common name for the aromatic compound with an amino group is aminobenzene, often referred to as aniline. When it is modified through the process of nitration, the added -NO₂ group is called a nitro group. The various positionings relative to the amino group (ortho, meta, and para) dictate the nomenclature of the resulting compounds. Ortho and para positions are preferred typically, but under certain reaction conditions, the meta position can also be favored.