Trinitrobenzene, sym

Three isomers of trinitrobenzene are known 1,3,5-trinitrobenzene (sym-tri-nitrobenzene), 1,2,4-trinitrobenzene and 1,2,3-trinitrobenzene ... 

Reaction specific to sym-trinitrobenzene. Sym-trinitrobenzene in acetone solution rapidly produces a red colour with alkali hydroxides or ammonia. In the absence of the solvent the colour develops slowly. 

Trinitrobenzene (sym-ti nitrobenzene, TNB) may be prepared only with the greatest difificulty by the nitration of m-dinitrobenzene. Hepp first prepared it by this method, and Hepp and Lobry dc Bruyn improved the process, treating 60 grams of m-dinitrobenzene with a mixture of 1 kilo of fuming sulfuric acid and 500 grams of nitric acid (d. 1.52) for 1 day at 100 and for 4 days at 110 . Claus and Becker obtained trinitrobenzene by the action of concentrated nitric acid on trinitrotoluene. Trinitrobenzoic acid is formed first, and this substance in the hot liquid loses carbon dioxide from its carboxyl group. 

Other Names 1,3,5-Trinitrobenzene 2,4,6-Trinitrobenzene NSC 36931 TNB TNB (nitro compound) Trinitrobenzene i-Trinitrobenzene sym-Trinitrobenzene CA Index Name Benzene, 1,3,5-trinitro-CAS Registry Number 99-35-4 Merck Index Number 9726 Chemical Structure... 

In the nitration of benzene, wj-dinilro- and sym-trinitrobenzenes are obtained under more vigorous conditions. With naphthalene, 1-nitronaphthalene is the first product and further nitration gives a mixture of 1,5- and 1,8-dinitronaphthalenes 2-nitronaphthalene is never obtained. 

Synonyms CCRIS 1299 EINECS 204-289-6 Entsufon 1-Methyl-2,4,6-trinitrobenzene 2-Methyl-l,3,5-trinitrobenzene NCI-C56155 NSC 36949 TNT 2,4,6-TNT a-TNT TNT-tolite Tolit Tolite Trilit Trinitrotoluene sj/ 3-Trinitrotoluene Trinitrotoluol a-Trinitrotoluol sym-Tx -nitrotoluol Tritol Triton Trotyl Trotyl oil UN 0209 UN 1356. 

Dinitro-p-cresol 2,4,6-rTrinitroaniline (Picramide) sym-Trinitromesytylene (1,3,5-Triraethyl-2,4,6-trinitrobenzene) 2,4,6-Trinitroresorcinol (Styphnic Acid) 2-Amino-... 

As a starting material for the preparation of sym-trinitrotriazidobenzene, 1,3,5-trichlorobenzene is used. It is obtained by the chlorination of aniline and the removal of the amino group. Nitration to the trinitro derivative is described in Vol. I. The final reaction is simple powdered 1,3,5,-trichloro-2,4,6-trinitrobenzene is added to an aqueous alcohol solution of sodium azide. The precipitated product is washed with alcohol and water and dried at a moderate temperature. The product so obtained may be purified by crystallization from chloroform. 

Hackel and Kuboszek [30] have examined the eutectics of both forms of DEGDN with sym-trinitrobenzene and a-trinitrotoluene (Table 22). 

It was first prepd in 1923 by Turek on treating 2,4,6-trichloro-l,3,5-trinitrobenzene with an alkali azide in ale, acet or w soln. It can be obtained also from aniline by chlorination to sym-trichloro-aniline, followed by diazotization, treatment with ale to give sym-trichlorobenzene, nitration with mixed nitric-sulfuric acid to trinitrotrichloro-benzene and finally treatment with an ale soln of Na azide(Refs 3,5,6a 8)... 

Oxidation of nitro compounds to nitrophenols is another example of a nucleophilic reaction. Thus, m- dinitrobenzene and sym- trinitrobenzene were oxidized in an alkaline medium when boiled with potassium ferricyanide solution (Hepp[45]) ... 

Holleck and Perret [51] gave the following diagrammatic presentation of nucleophilic addition of the OH" or CN" ion to sym- trinitrobenzene in alkaline medium (X=OH" or CN") ... 

With regard to the other coloured compounds formed from m- dinitrobenzene or sym- trinitrobenzene, it was claimed that the carbanion of active methylene compounds condenses with the nitro compound in terms of nucleophilic substitution ... 

Dinitrotoluene does not give this reaction. Trinitro compounds (such as sym-trinitrobenzene and a- trinitrotoluene) also give the colour reaction but this is less typical, as the trinitro compounds give a similar colour with alcoholic NaOH alone without primary nitroparaffins. 

A number of authors have studied the emission spectra characteristics of many complexes of sym-trinitrobenzene (TNB) with aromatics (Reid [119] Bier and Ketelaar [120] Bier [121] Czekalla, Briegleb etal. [122] McGlynn Mid Boggus [123]). These experiments led to the conclusion that in most complexes the emission is a charge transfer (E -> N) emission. 

A detailed list of addition compounds formed by sym- trinitrobenzene, 2,4,6-trinitrotoluene, picric acid and other polynitro compounds is given in the appropriate paragraphs devoted to these nitro compounds. 

It is important to add that some molecular addition compounds of sym- trinitrobenzene with hydrocarbons can serve for identification and purification of hydrocarbons (Veibel [141]). Trinitrofluorenone seems to be of particular value (Orchin and Woolfolk [142], Lepley [154]). 

All the isomers are crystalline, pale yellow products and are poisonous. In addition, sym-trinitrobenzene causes severe irritation of the skin. 1,3,5-Trinitrobenzene can be formed in poor yield by the action of a mixture of anhydrous nitric acid and fuming sulphuric acid on m- dinitrobenzene, the 1,2,4-isomer also being formed in a very small quantity. The 1,2,3-isomer can be obtained only by indirect methods. 

According to Jefremov and Bogoyavlenskii [37] sym-trinitrobenzene exists in two isomorphic forms, which melt at 122.5°C and 106.3°C respectively. 

The solubility of sym-trinitrobenzene in various solvents according to Orlova [3] is given in Table 41. 

It was Hepp [30] in 1882 who first found that sym-trinitrobenzene forms a dark coloured substance with sodium alcoholate. V. Meyer [38] isolated a similar substance in 1896 when treating sym-trinitrobenzene with potassium alcoholate, and assigned the following structure to it ... 

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