Toluene nitro derivatives

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... 

Toxicity. Picric Acid is more toxic than the nitro derivatives of toluene, xylene or naphthalene. It is, however, much less toxic than nitro derivatives of benzene... 

HNS (7.5) can be prepared by many methods these include the reaction of nitro derivatives of toluene with benzaldehyde, the reaction of nitro derivatives of benzyl halogenides with alkaline agents by removing hydrogen halogenide, and the oxidation of nitro derivatives of toluene. 

Addition of nitro compounds (such as nitro derivatives of benzene and toluene) neither changes the pH nor the shape of the curve. 

The action of fuming nitric acid transforms benzene and its homologues (toluene, xylene) into nitro-compounds (nitrobenzene, etc.), which remain in the acid liquid, from which the mineral oil is subsequently separated. The liquid is then diluted with as much water and the solution neutralised with caustic soda solution and extracted with ether. The ethereal liquid (dried with a few granules of caldum chloride and filtered) is evaporated at a gentle heat and the residue weighed. If tar oils are present, this residue will consist of a reddish-brown oily liquid, heavier than water and with the odour characteristic of aromatic nitro-derivatives. The weight found, divided by 1-15 (mean sp. gr. of aromatic nitro-compounds), will give the volume. 

The Dinitro Methoxy Toluenes. See in Vol 3, C556-R to C557-L under Nitro Derivatives of Cresol . The CA Registry No for these compds is [50741-92-9]... 

The most important feature of the spectra is the large blue shift of the sulfones vs the nitro derivatives, i.e., 53 nm (3098 cm 1) for the stilbene, and 30 nm (1400 cm 1) for the azobenzene derivatives, in toluene). These large blue shifts suggest that sulfonyl compounds are more transparent in the visible region than their nitro... 

No general experimental details for the preparation of nitro derivatives can be given, as the ease of nitration and the product formed frequently depend upon the exact experimental conditions. Moreover some organic compounds react violently so that nitrations should always be conducted on a small scale. Typical procedures for benzene hydrocarbons are illustrated by the following concise notes for the nitration of benzene and toluene to yield the solid dinitro compounds. (Full experimental details are given in Expts 6.17 and 6.18). 

Titov used the following technique for the nitration. A mixture of hydrocarbon and aluminium chloride was saturated with nitrogen dioxide. An exothermic reaction took place, A1C13 being dissolved. The intensity of the reaction diminished after all the aluminium chloride had been dissolved. The saturation of the mixture with N02 was stopped at 95% of the theoretical amount. Then the unreacted nitrogen dioxide was expelled by passing C02. The liquid nitro compound phase was separated from the solid aluminium salt. The yield of the nitro derivatives of toluene and chlorobenzene was 88% and 96% of theoretical for toluene and chlorobenzene respectively. 

Niementowski reacted sodium nitrite with a solution of 3,4-bis(dimethylamine)-toluene in acetic acid and obtained a nitro derivative ... 

Toluene also yields nitro derivatives of o- and p- cresol besides nitrotoluenes... 

Nitro derivatives of benzene, when boiled with sodium hydroxide in methyl alcohol solution are reduced to azoxy compounds (pp. 31, 237, 251). Nitro derivatives of toluene under these conditions are oxidized to nitro derivatives of stilbene (pp. 70, 283, 302). 

This would explain a number of reactions of the methyl group in nitro derivatives of toluene, particularly in trinitrotoluene. For example, formaldehyde can... 

The methyl group in nitrotoluenes reacts with benzaldehyde much more readily than that of toluene itself, giving the corresponding derivatives of stilbene. Mono-, di- and tri-nitrotoluenes also react with p- nitrosodimethylaniline to form the corresponding anils. Such a product is not obtained in the case of toluene (Sachs and Kempf [34]). The methyl group of 2,4-dinitrotoluene also reacts with pyridine N-oxide in the presence of iodine to yield 2,4-dinitrobenzaldehyde [155], Poray-Koshits and Chizhevskaya [35] found that di- and trinitrotoluenes react with phthalic anhydride to form nitro derivatives of benzylidenephthalide ... 

On boiling nitro derivatives of toluene with sodium hydroxide, their methyl group is readily oxidized, forming a methine group and nitro derivatives of stilbene. 

Fig 50. Heats of formation of nitro derivatives of benzene and toluene (a) and heats of nitration of benzene and toluene (b) in kcal/mole. (Garner and Abernethy [50]). 

Of all nitro derivatives of toluene, trinitrotoluene is the most important as an explosive. It is by the most often used high explosive among those derived from aromatic compounds. It is popular because it is simple and relatively safe to manufacture, Mid has high explosive power, and above all because its high chemical stability and low sensitiveness to impact and friction make it safe to handle. In addition, its toxicity is low and thus it compares favourably in this respect with the nitro derivatives of benzene. 

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