In the method of preparing aniline from benzene, benzene is first treated with nitric acid. In the process of treatment, benzene is nitrated by nitric acid to form nitrobenzene, and then nitrobenzene is reduced by hydrogen to obtain aniline. The benzene used at that time was mainly obtained from diphenyl ethanol ketone resin, and the source was quite small.

You want to write a paper to understand Hoffman (august wilhelm hofmann 18 18- 1892) and his Hoffman theory.