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Nitroderivatives

An NO2 group can be introduced into an alkyl chain by nucleophilic substitution with silver nitrite. But what is the point of preparing a nitroalkane?

Preparation of 1-nitrooctane from 1-iodooctane and AgNO₂ (83%)
Acidity of nitromethane (pKa = 10): its conjugate base is resonance-stabilized by the nitro group

The most important property of nitroalkanes is the high acidity of the hydrogens bonded to the carbon bearing the NO2 group.

A CH2 group next to an NO2 group is about five orders of magnitude (100,000 times) more acidic than an alcohol and as acidic as a phenol.

The carbanion is formed very easily and can carry out nucleophilic attacks, either substitutions or additions:

Reactions of the nitromethane anion: epoxide opening, addition to cyclohexanone and substitution of a tosylate, followed by reduction of the nitro group to an amine or by a new reaction with acetaldehyde

Reduction of the nitro group gives amines.

Moreover, once the nitroalkane has reacted, it can be made to react again if it still has alpha hydrogens.