Nitro group reduction

The chemical reactions described as reduction of nitro compounds can be effected by many reagents and reaction conditions. Historically, the nitro group was one of the first functional groups to be reduced.

Alkyl and aryl nitro compounds behave differently. Thus, reduction conditions can be broadly classified by starting materials: aliphatic nitro compounds or aromatic nitro compounds. Secondary classifications are based upon reaction products.

Hydrodenitration (replacement of a nitro group with hydrogen) is difficult to achieve but can be effected by catalytic hydrogenation over platinum on silica gel at high temperatures.

Aliphatic nitro compounds can be reduced to aliphatic amines by several reagents:

α,β-Unsaturated nitro compounds can be reduced to saturated amines by:

Aliphatic nitro compounds can be reduced to aliphatic hydroxylamines using diborane.

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