Constructing Bromoaniline, the Building Block

4-bromoaniline was synthesized in multiple steps starting from nitrobenzene using a route that require a protection group strategy.

This strategy shows how creating exceptional electrophiles affects the reaction conditions to make them suitable for electrophilic aromatic substitution. First nitrobenzene was reduced to aniline. The aniline produced in the first step was then acetylated using acetic anhydride to yield acetanilide. Next, the acetanilide was brominated utilizing Br₂ and the para- isomer was collected through recrystallization. In the final step, acid and heat were used to eliminate the acetate attached to the nitrogen atom, to yield 4-bromoaniline. The successes of these reactions were assessed by IR, melting point, and NMR. Bromoaniline is a useful intermediate in the synthesis of biphenyl, which is a key chemical for creating products that protect crops from molds and fungi. Biphenyl is also useful for making greener types of plastic.