Nitro compound

Nitro compounds are organic compounds in which one or more nitro groups (- NO2) bonded to each carbon atom of an organic radical. One can distinguish between aliphatic and aromatic nitro compounds. The aromatic are generally more stable. Organic compounds with nitro groups on nitrogen atoms (N- nitro compounds ) are called nitramines.

Aromatic nitro compounds

The aromatic nitro compounds (often nitroaromatics ) can be prepared directly by electrophilic aromatic substitution with nitrating acid.

The simplest nitroaromatic is nitrobenzene. Among the best known representatives include the explosives trinitrotoluene, picric and styphnic. In addition to the group of nitroaromatic explosives also includes dyes, pharmaceuticals, herbicides, raw materials for the plastics industry and synthetic fragrances (eg, nitro musks, now fallen into disrepute ). In the chemical industry nitroaromatics are important intermediates because they are needed for the production of aromatic amines (e.g., aniline, which is synthesized from nitrobenzene ) - see BASF.

Nitroaromatics as environmental toxins

Many nitroaromatic compounds are environmental toxins and as such a (waste) problem dar. Thus, the soils and groundwater in the area of former explosives factories still contaminated, for example, in Germany with nitroaromatics.

Aliphatic nitro compounds

Aliphatic nitro compounds can be prepared, inter alia, by nucleophilic substitution of alkyl halides with inorganic nitrites, such as silver nitrite, AgNO2 or sodium nitrite, NaNO2.

You are synthetically versatile. So they can be used for example in a Henry reaction ( nitro - aldol reaction ). The nitro compounds thus obtained may also be converted by reduction to the aliphatic amines, or a Nef reaction in further reaction steps to give ketones. Meaning they possess as intermediates in the chemical industry as a solvent or fuel.

Distinguishing nitro and nitrite groups

In the preparation of nitro compounds is produced in a side reaction, and the ester of nitrous acid ( nitrite ) still as a by- product. The percentage, however, is the reaction path dependent. The difference in the valence of the nitrogen. The nitro group is bonded via the nitrogen atom on the carbon atom. The isomeric nitrite group, the nitrogen is trivalent and bonded via an oxygen atom on the carbon. Nitroalkanes are temperature stable than nitrite ester.