Mannheim of 1848, the city was a centre for political and revolutionary activity. In 1865, Friedrich Engelhorn founded the "Badische Anilin- und Soda-Fabrik" (Baden Aniline and Soda Factory, BASF) in Mannheim, but the factory was constructed across the Rhine in Ludwigshafen because Mannheim residents feared air pollution from its operations. From this dye factory, BASF has developed into the largest chemical company in the world. After opening a workshop in Mannheim in 1871 and patenting engines from 1878, Karl Benz patented the first motor car in 1886. He was born in Mühlburg (now part of Karlsruhe). The Schütte-Lanz company, founded by
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