Aniline Germany. Today, the name of BASF, originally "Badische Anilin- und Soda-Fabrik" (English: Baden Aniline and Soda Factory), now the largest chemical supplier, echoes the legacy of the synthetic dye industry, built via aniline dyes and extended via the related azo dyes. The first azo dye was aniline yellow. In the late 19th century, aniline emerged as an analgesic drug, its cardiac-suppressive side effects countered with caffeine. During the first decade of the 20th century, while trying to modify synthetic dyes to treat African sleeping sickness, Paul Ehrlich – who had coined the term "chemotherapy" for his "magic bullet" approach to
Aniline as benzeneazophenol, in a process called "coupling". It reacts with nitrobenzene to produce phenazine in the Wohl-Aue reaction. Hydrogenation gives cyclohexylamine. Being a standard reagent in laboratories, aniline is used for many niche reactions. Its acetate is used in the Aniline acetate test for carbohydrates, identifying pentoses by conversion to furfural. It is used to stain neural RNA blue in the Nissl stain. The largest application of aniline is for the preparation of methylene dianiline and related compounds by condensation with formaldehyde. The diamines are condensed with phosgene to give methylene diphenyl diisocyanate, a precursor to urethane polymers. Other uses