Nitro compound
From Biocrawler, the free encyclopedia.
Nitro compounds are organic compounds that contain one or more nitro functional groups (NO2). They are often highly explosive; various impurities or improper handling can easily trigger a violent exothermic decomposition.
Aromatic nitro compounds are typically synthesized by the action of a mixture of nitric and sulfuric acids on a suitable organic molecule. Some examples of such compounds are trinitrophenol(picric acid), trinitrotoluene(TNT), and trinitroresorcinol(styphnic acid).
| Contents |
[edit]
Preparation
In organic synthesis various methods exists to prepare nitro compounds.
[edit]
Aliphatic nitro compounds
- nitromethane adds to aldehydes in 1,2-addition in the nitroaldol reaction
- nitromethane adds to alpha-Beta unsaturated carbonyl compounds as a 1,4-addition in the Michael reaction as a Michael donor
- nitroethylene is a Michael acceptor in a Michael reaction with enolate compounds.
- in nucleophilic aliphatic Substitution sodium nitrite (NaNO2) replaces an alkyl halide
[edit]
Aromatic nitro compounds
- in electrophilic substitution nitric acid reacts with aromatic compounds in nitration
[edit]
Reactions
Nitro compounds participate in several organic reactions.
[edit]
Aliphatic nitro compounds
- aliphatic nitro compounds are reduced to amines with hydrochloric acid and a iron catalyst
- hydrolysis of nitro compounds yield aldehydes or ketones in the Nef reaction
[edit]
Aromatic nitro compounds
- reduction of Aromatic nitro compounds give anilines with hydrogen gas over a platinum catalyst
- in nucleophilic aromatic substitution the nitro group is replaced by the hydroxide anion to a phenol and by an alkoxy nucleophile to an aryl ether.
