Aliphatic nitro compounds
Reduction to hydrocarbons
Hydrodenitration (replacement of a nitro group with hydrogen) is difficult to achieve, but can be completed by catalytic hydrogenation over platinum on silica gel at high temperatures.
Reduction to amines
Aliphatic nitro compounds can be reduced to aliphatic amines using several different reagents:
Catalytic hydrogenation using platinum(IV) oxide (PtO2) or Raney nickel
Iron metal in refluxing acetic acid
Samarium diiodide
,-Unsaturated nitro compounds can be reduced to saturated amines using:
Catalytic hydrogenation new era colorado rockies purple caps over palladium-on-carbon
Iron metal
Lithium aluminium hydride (Note: Hydroxylamine and oxime impurities are typically found.)
Reduction to hydroxylamines
Aliphatic nitro compounds can be reduced to aliphatic hydroxylamines using diborane.
Reduction to oximes
Nitro compounds are typically reduced to oximes using metal salts, such as stannous chloride or chromium(II) chloride. Additionally, catalytic hydrogenation
Aromatic nitro compounds
The reduction of aryl nitro compounds can be finely tuned to obtain a different products typically in high new era colorado rockies purple caps yields.
Reduction to anilines
Many methods for the production of anilines from aryl nitro compounds exist, such as:
Catalytic hydrogenation using palladium-on-carbon, platinum(IV) oxide, or Raney nickel
Iron in acidic media (Note: Iron is particularly well suited for this reduction as the reaction conditions are typically gentle and also because iron has a high functional group tolerance.) (See Bechamp reduction)
Sodium hydrosulfite
Sodium sulfide (or hydrogen sulfide and base)
Tin(II) chloride
Titanium(III) chloride
Zinc
Samarium
It is also possible to form a nitroaniline by reduction of a dinitroarene using sodium sulfide.
Metal hydrides are typically not used to reduce aryl nitro compounds to anilines because they tend to produce azo compounds. (See below)
Reduction to hydroxylamines
Several methods for the production of aryl hydroxylamines from aryl nitro compounds exist:
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