Hydrocarbons, with Nitro

Likewise the mechanism of nitration of an aromatic hydrocarbon with nitro-... 

In mononitration the hazard is due to the extremely violent reaction of the unreacted hydrocarbon with the MA, and to the fact that nitro derivatives of cresols are formed in the process, along with nitro toluenes. The last stage — trinitration — is dangerous due to the drastic conditions of the reaction which requires coned acids and a high temp. The earlier method of trinitration at which temps up to 120° were applied was particularly hazardous. If the mono-nitre toluene hns not b n freed from nitro-cresols, trinitration is still more dangerous, due to the high reactivity of nitrocresols, and their liability to undergo oxidation... 

The silica gel surface is extremely polar and, as a result, must often be deactivated with a polar solvent such as ethyl acetate, propanol or even methanol. The bulk solvent is usually an n-alkane such as n-heptane and the moderators (the name given to the deactivating agents) are usually added at concentrations ranging from 0.5 to 5% v/v. Silica gel is very effective for separating polarizable materials such as the aromatic hydrocarbons, nitro hydrocarbons (aliphatic and aromatic), aliphatic ethers, aromatic esters, etc. When separating polarizable substances as opposed to substances with permanent dipoles, mixtures of an aliphatic hydrocarbon with a chlorinated hydrocarbon such as chlorobutane or methylene dichloride are often used as the mobile... 

It has been recently described [55d) that aliphatic nitrile oxides can be formed in solution by treating an aliphatic a-nitro-hydrocarbon with phenylisocyanate in the presence of a catalytic amount of tri-ethylamine. Dehydration of the nitro compounds occurs with the con-committant formation of benzoylurea. From nitroethane, the reaction is formulated as follows ... 

Yu, S., D. Herreno-Saenz, D. W. Miller, F. F. Kadlubar, and P. P. Fu, Mutagenicity of Nitro-Polycyclic Aromatic Hydrocarbons with the Nitro Substituent Situated at the Longest Molecular Axis, Mutat. Res., 283, 45-52 (1992). 

Benzin is a mixture of various hydrocarbons. It has, therefore, no sharp boiling point, but distils within rather wide limits. The testing of benzin for benzene by nitrating the latter with nitro-sulphuric acid was not adopted here, because it is impossible to obtain a benzin that will stand this test. 

Nitro compounds can be prepared in a number of ways, including the direct substitution of hydrocarbons with nitric acid,... 

Nitroparaffins such as nitromethane, nitro-ethane, nitropropane, are mild oxidizers and should not be heated with easily oxidized hydrocarbons. With water, they form nitronic acids as tautomeric forms, which form explosive salts with inorganic bases (Ref 83)... 

Many polycyclic aromatic amines and aldehydes are commercially available, but their supply is very limited. Preparation of these starting materials is necessary for studying the (3-lactam formation reaction [93]. Nitro compounds are the precursors for the amines. An important task was to prepare polycyclic aromatic nitro compounds, particularly those of chrysene, phenanthrene, pyrene, and dibenzofluorene in good yield. Nitration of these hydrocarbons with concentrated nitric acid in sulfuric acid is a widely used reaction for this purpose. Our research culminated in facile synthesis of polyaromatic nitro derivative 9 starting from polyaromatic hydrocarbons (PAHs) 8 through the use of bismuth nitrate impregnated with clay (Scheme 1) ([94, 95] for some examples of bismuth nitrate-catalyzed reactions... 

Nitration is the insertion of a nitro group (-N02) into an organic compound, usually through the agency of the reaction of a hydrocarbon with nitric acid. Concentrated sulfuric acid may be used as a catalyst. 

Konovalov [15] nitrated aliphatic hydrocarbons in sealed tubes at 120-130°C, using dilute nitric acid of concentration 6.5-19%. From normal hydrocarbons he obtained secondary nitro compounds in yields varying from 40% (2-nitro-hexane from hexane) to 49-50% (2-nitrooctane from octane). Aromatic hydrocarbons with an aliphatic substituted group when nitrated under the same conditions gave nitro derivatives with a nitro group in the side chain. For example, ethylbenzene, when nitrated with 12.5% nitric acid at 105-108°C, gives phenyl-nitroethane in 44% yield. The optimum yield is obtained with 13% acid. 

Nitration of aromatic hydrocarbons with a side chain gives mononitro compounds with the nitro group attached either to the ring or to the side chain, with a predominance of the former. For example, from toluene at temperature 14-15°C, 46% of nitrotoluenes and 9% of phenylnitromethane were obtained. 

The ability to form addition compounds, especially with aromatic hydrocarbons composed of condensed rings, is one of the specific properties of aromatic poly-nitro compounds. For example, compounds of trinitrobenzene or picric acid with naphthalene, as well as with other hydrocarbons with condensed rings, are very characteristic. Generally they are intensely coloured. 

This group (—NO2), is the residue of nitric acid, HO—NO2, left when the acid hydroxyl is removed. It is known as the nitro groups and compounds containing it as nitro compounds. Some of the higher paraffin hydrocarbons yield nitro compounds when heated with dilute nitric acid under pressure by the reaction... 

Nitro Products.—(a) Benzene and its homologous hydrocarbons readily form nitro-suhstitution products when treated with nitric acid, whereas the paraffin hydrocarbons form nitro-substitution products only indirectly, CeHs—NO2, nitro benzene. 

The advantages of the nitration circuit method are as follows low oxidation tue to the short contact time of the hydrocarbon with the acid, full nitric acid itilization, safety due to a very small quantity of the nitro compound in the ircuit. 

Nitro derivatives of cyclohexane can be obtained by the method of Severin (Chapter IV, formula 16) while reducing some nitroaromatic hydrocarbons with Grignard reagent or with sodium borohydride. Sodium borohydride reduced 1,3,5-tiiniirobenzene to 13,5-lrinitrocydohexane (Vol. I. p. 252). 

When a molecule contains electronegative substituens isotope exchange is simpler than it is with hydrocarbons. It occurs relatively readily with nitro-alkanes, alkyl cyanides, monochloroacetic acid, acetamide, and similar compounds. The following prescription has been given for the preparation of [1,1-D2] nitroethane 8 5... 

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