2:4: 6*Trinitrobenzoic acid

Place 25 g. of phenylacetic acid (Section IV,160) in a 500 ml. round-bottomed flask, cool the latter in running water and add 250 ml. of fuming nitric acid, rather slowly at first and then more rapidly. The addition occupies about 15 minutes. Attach a condenser to the flask, reflux the solution for 1 hour, and pour into about 500 ml. of cold water. When cold, filter the crude 2 4-dinitrophenylacetic acid at the pump and wash it with cold water the resulting acid, after drying at 100°, is almost pure (m.p. 181°) and weighs 31 g. Recrystallise it from 300 ml, of 20 per cent, alcohol. Collect the first main crop (25 g.), and allow the mother liquor to stand overnight when a further 2 g. of pure acid is obtained dry at 100°, The yield of pure 2 4-dinitrophenylacetic acid, m.p. 183°, is 27 g. 

Other Names l-Carboxy-2,4,6-trinitrobenzene 2,4,6-Trinitrobenzoic acid NSC 133453 TNBA  

Trinitrobenzoic acid sym-Trinitrobenzoic acid CA Index Name Benzoic acid, 2,4,6-trinitro-CAS Registry Number 129-66-8 Merck Index Number 9727 Chemical Structure 

Chemical/Dye Class Nitro Molecular Formula C7H3N3O8 Molecular Weight 257.11 pH Range 12.0-13.4 

Solubility Solubler in water, ethanol, methanol, ether, acetone 

Boiling Point (Calcd.) 435.8 + 45.0°C Pressure 760 Torr Synthesis Synthetic methodsi-s 

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If the alcohol is required for conductivity or other physico-chemical work and traces of bases are objectionable, these may be removed by redistillation from a little 2 4 6-trinitrobenzoic acid. This acid is selected because it is not esterified by alcohols, consequently no water is introduced into the alcohol. 

Trinitrobenzoic acid, 2,4,6-trinitrobenzoic acid (indicator) dissolve 0.1 g in 100 mL water pH range colorless 12.0-13.4 orange-red. 

Trinitrobenzoic acid [129-66-8] water. Dried in a vacuum desiccator. 

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... 

Trinitrobenzoic acid has been prepared by heating trinitrotoluene with fuming acid in a sealed tube to ioo°, for two weeks,1 the oxidation being only partial. It can also be prepared by heating trinitrotoluene under a reflux condenser, with a mixture of 5 parts of concentrated nitric acid and 10 1 Ber. 8, a 3 (1870). 

Some substrates like benzoic acid, benzaldehyde etc. are so deactivated that direct nitration to their trinitro derivatives is not possible. Direct nitration of benzoic acid with excess fuming nitric and concentrated sulfuric acids at a temperature of 145 °C for several hours results in the formation of 3,5-dinitrobenzoic acid (54-58 %). The use of oleum in such reactions can significantly reduce the rate of nitration due to carbonyl protonation (see Section 4.3.3). Consequently, indirect routes are used for the synthesis of polynitroarylenes like 2,4,6-trinitrobenzoic acid and 2,4,6-trinitrobenzaldehyde (Section 4.9). 

Other examples of oxynitration include the formation of (1) 2,4,6-trinitro-m-cresol from toluene, (2) 2,4-dinitronaphth-l-ol from naphthalene, (3) 3-chloro-2,4,6-trinitrophenol from chlorobenzene and (4) 3-hydroxy-2,4,6-trinitrobenzoic acid from benzoic acid. ... 

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... 

The dehydration of A,A -diacylhydrazines is a standard method for the formation of the 1,3,4-oxadiazole ring. 2,5-Dipicryl-l,3,4-oxadiazole (DPO) (19) is synthesized by treating 2,4,6-trinitrobenzoic acid (17) with phosphorous pentachloride, followed by treatment with hydrazine to give the A, A -diacylhydrazine (18) which undergoes dehydration on further reaction with phosphorous pentachloride in 1,2-dichloroethane. DPO exhibits high thermal stability but is very sensitive to impact and shock, making it useful in detonation transfer compositions. 

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