Nitrogruppi

Nitrogruppi is a term used in organic chemistry to refer to the nitro group. The nitro group is a functional group with the chemical formula -NO2. It consists of a nitrogen atom bonded to two oxygen atoms. One oxygen atom is double-bonded to the nitrogen, while the other is single-bonded and carries a formal negative charge. The nitrogen atom itself carries a formal positive charge. This arrangement results in a resonance structure where the positive and negative charges are delocalized between the nitrogen and oxygen atoms.

The nitro group is strongly electron-withdrawing due to the high electronegativity of oxygen and the positive formal charge on nitrogen. This electron-withdrawing effect significantly influences the reactivity of organic molecules containing the nitro group. For instance, it can make adjacent hydrogen atoms more acidic and can deactivate aromatic rings towards electrophilic aromatic substitution.

Nitro compounds are synthesized through various methods, most commonly by nitration reactions, which involve the introduction of a nitro group into an organic molecule. A classic example is the nitration of benzene using a mixture of concentrated nitric acid and sulfuric acid. The nitro group can also be introduced through oxidation of amines or by nucleophilic substitution reactions.

The nitro group is a versatile functional group found in a wide range of organic compounds. Many explosives, such as nitroglycerin and TNT (trinitrotoluene), contain nitro groups. Nitro compounds also play important roles in pharmaceuticals, dyes, and pesticides. For example, nitrofurantoin is an antibiotic, and nitrobenzene is a precursor to aniline, which is used in the production of dyes and polymers. The reduction of the nitro group is a common transformation, often leading to the formation of an amine group.