There are different ways of obtaining aniline.The feedstock material is nitrobenzene having the formula C6H5NO2.Initially nitrobenzene was directly hydrogenated using the catalysts and high temperatures.The reaction proceeds as follows: C6H5NO2 + 3H2 = C6H5NH2 + 2H2O.Its advantage - simplicity and low cost of the reagents.Disadvantage - the low yield of the desired product.
In 1842, the Russian chemist Nikolai Zinin experimentally found a much more efficient method of converting nitrobenzene to aniline.He is exposed to nitrobenzene ammonium sulfide.The reaction proceeds as follows: S
6H5NO2 +3 (NH4) 2S = C6H5NH2 + 6NH3 + 3S + 2H2O.
addition to aniline formed elemental sulfur and ammonia is released, which immediately binds to partially water.Description of this reaction is impressed on the scientific world.One of the most prominent chemists in this regard, said: "If Zinin did not do anything more, except for the conversion of nitrobenzene to aniline, and even then his name would remain written in golden letters in the history of chemistry!".The above reaction is still considered a special case of the so-called"Reactions Zinin."
can get from aniline and nitrobenzene by reduction of iron powder in the presence of water vapor.The reaction proceeds as follows: 4S6H5NO2 + 9Fe + 4H2O = 4C6H5NH2 + 3Fe3O4.