Aniline is mainly used to prepare methylene diphenylamine and related compounds by condensation with formaldehyde. The condensation of diamine with phosgene yields methylene diphenyl diisocyanate, which is the precursor of polyurethane polymers.

Other uses include rubber-processing chemicals (9 percent), herbicides (2 percent) and dyes and pigments (2 percent). As additives of rubber, aniline derivatives such as phenylenediamine and diphenylaniline are antioxidants. An example of a drug prepared from aniline is acetaminophen (paracetamol, tylenol). Aniline's main use in the dye industry is as a precursor of indigo (the blue color of blue jeans).

history
Aniline was first isolated by Otto Unverdorben in 1826 by the destructive distillation of indigo. He calls it a crystal in. In 1834, Friedlieb Runge isolated a substance from coal tar that turned a beautiful blue when treated with lime chloride. He named it Kyanol or Cyanol. In 1840, Carl Julius Fritzsche (1808-1871) treated indigo with potash and obtained an oil that he named aniline, Named after anil (Indigofera suffruticosa), a plant that produces indigo. In 1842, Nikolay Nikolaevich Zinin reduced nitrobenzene and obtained a base which he named Benzidam. In 1843, August Wilhelm von Hofmann proved that these were all the same substance, which has since been called aniline or aniline.

Synthetic dye industry
In 1856, von Hoffmann's student William Henry Perkin discovered magenta while trying to synthesize quinine and went into industry to produce the first commercial synthetic dye. Other aniline dyes followed, such as magenta, saffron and inulin. When amaranth was found, aniline was expensive. Shortly thereafter, it was prepared "by the ton" using a method reported by Antoine Bechamp in 1854. The decline of Bechamp contributed to the development of a large-scale dye industry in Germany. Today, basF's name was originally Badische Anilin-und Soda-Fabrik. Baden Aniline and Soda-Fabrik), now the largest supplier of chemicals, echoes the tradition of the synthetic dye industry, building from Aniline dyes and extending dyes through related azo dyes. The first azo dye is aniline yellow.