1.3.5- Trinitrobenzene preparation

The Griesheim method is generally used for the laboratory preparation of sym-trinitrobenzene. However, it is too expensive to be applied in industry. Trinitrobenzene prepared in this way is much more costly than trinitrotoluene, whereas the gain in explosive power obtained is relatively small. 

Place 4 grams of the bis-urethan trinitrobenzene (prepared in step 2) into 100 milliliters of 98% sulfuric acid, and then heat the mixture to 70 Celsius for 3 hours while rapidly stirring. During the reaction, bubbles of gas are evolved and the solution slowly turns a deep red color. After 3 hours, remove the heat source and allow the reaction mixture to cool to room temperature. After which, add the cooled reaction mixture to 400 milliliters of ice water, and then filter-off the yellow precipitate. Then wash the... 

Prepare a mixture by adding 10.44 grams of 5-fluoro-l,3-diamino-2,4,6-trinitrobenzene (prepared in step 1), and 9.92 grams cyanotrimethylsilane into 200 milliliters of nitromethane. Afterwards, reflux the mixture at 100 Celsius for two hours. After refluxing the mixture for 2 hours, remove the heat source, and allow the mixture to cool to room temperature. Then filter the reaction mixture to remove any insoluble impurities. After which, recrystallize the crude product from the nitromethane, and then vacuum dry or air-dry the product. Then recrystallize the dry product from 200 milliliters of acetonitrile. After recrystallization, vacuum dry or air-dry the product. The yield of 5-cyano-l,3-diamino-2,4,6-trinitrobenzene will be 8.8 grams as orange-brown crystals with a melting point of 212 Celsius (with decomposes). 

Dinitrobenzofuroxan can be prepared by thermal decomposition of 1-azido-2,4,6-trinitrobenzene (prepared from l-chlor-2,4,6-trinitrobenzene) [13, 15] or more effectively, without isolation of l-azido-2,4,6-trinitrobenzene, directly from l-chlor-2,4,6-trinitrobenzene [31]. The other method of 4,6-dinitrobenzofuroxan synthesis is based on nitration of benzofuroxan (prepared from o-nitroanUine) [31-33]. 

Trinitrobenzene may be prepared by heating the sodium salt of 2 4 6-trinitrobenzoio acid with water ... 

Trinitrobenzene can be prepared by heating w-dinitro-benzene with nitric acid and sulfuric acid to 1200 1 by heating 2, 4, 6-trinitrotoluene with fuming nitric acid in a sealed tube at 180° for three hours 2 by heating 2, 4, 6-trinitrobenzoic acid or its sodium salt with water, alcohol, dilute sodium carbonate or other suitable solvent.3... 

The mother liquors and washings lose carbon dioxide on boiling, and the insoluble trinitrobenzene separates see preparation XXIV) after filtering, washing, and drying, it weighs 15-20 g. (4 to 6 per cent of the theoretical amount). 

Agrawal and co-workers prepared some energetic explosives containing nitrate ester, nitramine and aromatic C-nitro functionality within the same molecule and studied their thermal and explosive properties l-(2-nitroxyethylnitramino)-2,4,6-trinitrobenzene... 

Trinitrobenzene is present in crude TNT manufactured by mixed acid nitration and results from methyl group oxidation followed by decarboxylation." In fact, a convenient method for the synthesis of 1,3,5-trinitrobenzene involves oxidation of 2,4,6-trinitrotoluene with a solution of sodium dichromate in sulfuric acid, followed by decarboxylation of the resulting 2,4,6-trinitrobenzoic acid in boiling water." 1,3,5-Trinitrobenzene is prepared from 2,4,6-trinitro-m-xylene by a similar route." 2,4,6-Trinitroanisole can be prepared from the... 

Some nitro derivatives of benzofurazan have been investigated for their explosive properties. 4-Amino-5,7-dinitrobenzofurazan (56) has been prepared by a number of routes including (1) the thermally induced cyclodehydration of l,3-diamino-2,4,6-trinitrobenzene (55), (2) the nitration of 4-amino-7-nitrobenzofurazan and (3) the reduction of 4-amino-5,7-dinitrobenzofuroxan with triphenylphoshine. The isomeric 5-amino-4,7-dinitrobenzofurazan (57) has been prepared along similar routes. ... 

Benzenetrifuroxan (66) is a powerful explosive which was first synthesised by Turek in 1931 by heating 1,3,5-triazido-2,4,6-trinitrobenzene (65) to its melting point (131 °C) the latter prepared from the reaction of 1,3,5-trichloro-2,4,6-trinitrobenzene with sodium azide in aqueous ethanol. 

The 7i-donor behavior of 4-arylmethylene-2-phenyl-5(47/)-oxazolones 762 with the 7i-acceptor tetracyanoethylene has also been studied. The initially formed charge-transfer complex is converted via intermediate 763 to a new compound for which a 2-aryl-l-benzamido-3,3,4,4-tetracyanocyclobutanecarboxylic acid 764 has been proposed on the basis of the NMR spectral data (Scheme 7.233). Charge-transfer complexes of 2-aryl-4-arylidene-5(47/)-oxazolones with di- and trinitrobenzene as n acceptors have also been prepared. ... 

Beilstein Kuhlberg investigated nitration of toluene with mixed nitric-sulfuric acid of various concns and isolated for the first time several isomers of mono- and dinitro-toluene. They also prepd in 1870 TNT, but did not prepare Trinitrobenzene. At about the same time, mono-, di-, tri- and tetra-nitronaphthalenes were prepd (Ref 12, p 18). Trinitrobenzenes were prepd in 1882 by P. Hepp... 

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. 

Trichloro-2,4,6-trinitrobenzene is prepared by the nitration of trichlorobenzene with a mixture of nitric acid and sulfuric acid. 1,3,5-Trichloro-2,4,6-trinitrobenzene is then converted to l,3,5-trinitro-2,4,6-triaminobenzene (TATB) by nitrating with ammonia as shown in Reaction 7.4. The yellow-brown crystals of TATB are filtered and washed with water. 

Arylthiophenes are formed by reaction of 2-thienylcopper with iodoarenes (Scheme 182) (70ACS2379, 71ACS2428). A Meisenheimer complex (501) has been prepared from 2-thienylcopper and trinitrobenzene (71TL2713). 

CA 50,16332(1956) 14)M.Blais et al.PATR 2524(1959), "Preparation of Thermally Stable Explosives 2,4,6-Trinitrobenzene Derivatives (Conf Rpt, not used as a source of info)... 

M,Blais et aC Preparation of Thermally Stable Explosives 2,4,6-Trinitrobenzene Derivatives , PATR 2524 (1958) [Table 2 presents the expl properties of selected 2,4,6-TNB derivatives... 

Stock solutions (1000 mg/L in acetonitrile) of 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitrobenzene (TNB), 2,4-dinitrotoluene (2,4-DNT), and 4-amino-2,6-dinitrotoluene (4-Am-2,6-DNT) (Supelco). Sodium dodecyl sulfate (SDS) and sodium borate 10-hydrate. Standard solutions of the various explosives should be prepared daily (using the proper safety precautions) in an SDS-containing electrophoresis buffer. Platinum and silver wires, 0.1mm diameter. 

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