Polynitroaromatic compound

Zeman, S., "The Relationship between Differential Thermal Analysis Data and the Detonation Characteristics of Polynitroaromatic Compounds," Thermo-chimica Acta, 41 (1980). 

Polynitroaromatic compounds are used as explosives. They are toxic and might cause liver damage, methemoglobinemia and uncoupling of the oxidative phosphorylation process. Trace analyses of polynitroaromatic residues in groundwater, surface water, rainwater... 

It is widely stated in the usual reference texts that nitroaromatic compounds and more particularly polynitroaromatic compounds may present a severe explosion risk if subjected to shock, or if heated rapidly and uncontrollably, as in fire... 

It has been known for a long time that polynitroaromatic compounds produce colored products in contact with aUcafis [1]. These color reactions have been extensively used for the identification of nitroaromatic explosives. In the Janowski reaction [7], a solution of the polynitroaromatic compound (di- or trinitroaromatic) in acetone is treated with concentrated aqueous KOH solution. 1,3,5-Trinitrobenzene (TNB) and 2,4,6-trinitrotoluene (TNT), treated with 30% aqueous KOH, produced violet-red and red colors, respectively. Many variations of the Janowski reaction were reported, using KOH or NaOH in aqueous or ethanoHc solutions as reagents, and dissolving the explosives in acetone, ethanol or acetone-ethanol mixture [3,8]. The reaction was used both for spot tests and for spraying TLC plates [9]. 

Polynitroaromatic compounds were reported to undergo color reactions with numerous bases, such as ammonia in methanol [3] and aqueous solution of tetra-methylammonium hydroxide [10]. 

The structures of the colored products of the reactions between polynitroaromatic compounds and bases were first suggested by Meisenheimer [12]. They are usually described as resonance-stabilized complexes known as Meisenheimer complexes. Thus, the red-colored product of a reaction between TNB and sodium methoxide was assigned the following formula (1) ... 

It seems that the color produced in a reaction between bases and polynitroaromatic compounds consists of more than one substance. It was observed that the initial brown color in the reaction between TNT and sodium ethoxide changed slowly to purple [13, 14]. It was also assumed that the initial brown color was most probably a Meisenheimer... 

Lenke, H., C. Achtnich, and H.-J. Knackmuss, Perspectives of bioelimination of polynitroaromatic compounds . In Biodegradation of Nitroaromatic Compounds and Explosives, J. C. Spain, J. B. Hughes and H.-J. Knackmuss, Eds., Lewis Publishers, Boca Raton, FL, 2000, pp. 92-126. 

Glover E.G. Kayser, Quantitative Spectro-photometric Analysis of Polynitroaromatic Compounds by Reaction with Ethylenediamine , NOLTR-67-175 (1977) 68) S.S. Al-Kazraji... 

J.C. Hoffsommer J.F. McClullough, Quantitative Analysis of Polynitroaromatic Compounds by Combination of Thin-Layer Chromatography and Visible Spectrometry , JChromatogr 38, 508-14 (1968) 32) DX... 

Amperometric detection is the preferred method for the analysis of nitroaromatic explosives on microchip devices since it offers up to three orders of magnitude higher sensitivity than indirect LIF and it has a great potential for miniaturization and integration on microchip platform. Presence of nitrogroup allows its cathodic reduction to form al-kylhydroxyamines. The reduction mechanism of polynitroaromatic compounds is complex and depends on the number of nitro groups,... 

S. Zeman, Thermal Stabilities of Polynitroaromatic Compounds and their Derivatives, Thermochim. Acta, 31 (1979) 269. 

Picrates, especially salts of transition and heavy metals, such as nickel, lead, mercury, copper, and zinc picric acid is explosive but is less sensitive to shock or friction than its metal salts, and is relatively safe as a water wet paste Polynitroalkyl compounds, such as tetranitromethane and dinitroacetonitrile Polynitroaromatic compounds, especially polynitrohydrocarbons, phenols, and amines... 

Polynitroaromatic compounds are reduced more easily than mono-nitro compounds. Additional nitro groups facilitate the reduction however, the reduced functional groups, hydroxylamine and amine, hinder the reduction of other nitro groups. At pH < 3 the reduction of dinitroaromatic compounds follows two four-electron steps ... 

The hydrodynamic voltammograms of picric acid and p-nitro-phenol depicted in Figure 12 illustrate the influence of mechanism on the detection process. If the detector potential is set at the potential on the plateau of the voltammogram of p-nitro-phenol, both compounds are detected. If the potential is set at the plateau of the first wave of picric acid, it alone is detected. At more negative potentials the unit response for the polynitroaromatic compounds will be greater than the response for mononitroaromatic compounds since more electrons are involved in the electrochemical reduction of polynitroaromatics. 

However, Field, W. G. Gamer and Smith [138] had concluded earlier that proton transfers do not occur in liquid ammonia solutions of m- dinitrobenzene. On the basis of ultra-violet and visible absorption spectra and electrical conductance measurements of the products of interaction of polynitroaromatic compounds with a variety of amines, Miller and Wynne-Jones [139] came to the conclusion that ... 

Zeman, S. (1980). The relationship between differential thermal analysis data and the detonation characteristics of polynitroaromatic compounds. Thermochim. Acta, 41, 199-212. [275]... 

MEISENHEIMER-JANOVSKY Complex The adduct formed from a polynitroaromatic compound in alkaline solution with RO, HO (Meisenheimer) or with acetone (Janovsky) (see 1st edition). 

The anionic a complexes formed between polynitroaromatic compounds and bases (1, 2), commonly known as Meisenheimer complexes, are used as models of the reaction intermediates that are considered to be formed in activated nucleophilic aromatic substitution reactions (3-6), as well as being of intrinsic interest. Thus, numerous studies describe the formation and transformation of such a complexes (7-14). As a result, a variety of structural types of these species have been characterized and subjected to detailed investigation. A number of theoretical studies relating to these species have also been reported (15). 

A polynitroaromatic compound such as TNT reacts with an alkali such as potassium hydroxide to give an intensely coloured Jackson-Meisenheimer reaction product. When this reaction takes place in a ketone solution such as acetone, it is known as Janowsky reaction. In this paper, we slightly modify the approach by replacing acetone with DMSO. We have chosen DMSO as the solvent in our system because the DMSO droplets would be immiscible with the surrounding silicone oil while acetone would mix with the silicone... 

A Meisenheimer complex (7), a model for the -complex formed by nucleophilic attack of certain species on polynitroaromatic compounds, has been observed to fluoresce. The emission maximum is at 670 nm in acetonitrile and Of 0.09. It has been suggested that such a compound may be useful as a fluorescent biophysical probe.87 78 J. Blais and M. Gauthier, J. Luminescence, 1974, 9, 143. 

Polynitroalkyl compounds such as tetranitromethane and dinitroacetonitrile Polynitroaromatic compounds, especially polynitro hydrocarbons, phenols, and amines... 

EDS applications. In addition, new test data from the ACWA Program indicate that polynitroaromatic compounds (e.g., trinitrobenzoic acid and trinitrobenzene) precipitate during treatment of liquid wastes containing explosive residues, which may be present in EDS neutralents (Winkler, 2001). Electrochemical oxidation with Ce(IV) is also dropped from track two, owing to its relative immaturity and the possibility of corrosion and plugging of the electrochemical cells as a result of higher levels of metal ions in the EDS neutralents. 

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