2.4.6- Trinitrotoluene addition products

Tertiary nitro compounds, of course, do not undergo tautomeric transformation, and they might be expected to be resistant to alkalis. Nevertheless aromatic nitro compounds, and polynitro-ones in particular, are very sensitive to alkalis, and undergo transformation when treated with them. For example, sym-trinitrobcnzcnc and also a- trinitrotoluene, when reacted with potassium hydroxide in methyl alcohol solution, form dark addition products (see also p. 202). Under certain conditions the nitro group can break off to form high molecular compounds. 

The kinetics and mechanism of Meisenheimer s reaction has been studied by Caldin and Ainscough [43] who utilized the reactions of addition of sodium etho-xylate to trinitroanisole, trinitrobenzene and trinitrotoluene. By using temperatures in the range from -70°C to -100°C they were able to reduce the reaction rate to a measurable value. On treating the addition product with acetic acid at temperatures ranging from -50°C to -80°C they obtained the starting product. Thus, the reaction was proved to be reversible, as for example in the case of trinitroanisole (TNA) ... 

Hantzsch and Kissel [81] by treating trinitrotoluene with potassium alcoholate (e.g. methylate) obtained an addition product to which they ascribed the structure given earlier by Angeli [82] for the product obtained from trinitrobenzene and CH3OK (I). 

Stefanovich [88], on the basis of Meisenheimer s formulae, ascribes the formulae VII and VIII to the addition products of a- trinitrotoluene with two or three molecules of potassium alcoholate respectively. 

T. Urbanski and Pawlowski [89] investigated the salts formed on treating trinitrotoluene in acetone-alcohol solution with sodium alcoholate and also with an alcoholic solution of Ba(OH)2. Various addition products were obtained, according to the proportion of the alcoholate or hydroxide, e.g. ... 

Trinitrotoluene, like other highly nitrated aromatic hydrocarbons, easily forms addition products with polycyclic hydrocarbons and amines. The addition products formed by a- trinitrotoluene have been extensively studied by Hepp [35] and Kremann [104a,104b]. Some of the products are listed below (Table 69). 

Brady, Hewetson and Klein [139] tried to elucidate the mechanism of the reaction of sulphitation of unsymmetrical trinitrotoluenes. They assumed the formation of an addition product of sodium sulphite and the nitro compound in the first stage. 

In industrial practice, losses of crude TNT in the sulphitation process amount from 6 to 8%. Out of this 2%-3. 5% is ascribed to the loss of a- trinitrotoluene and 3.5-4.5% to that of unsymmetrical isomers and other impurities, such as tetrani-tromethane (p. 339) and trinitrobenzene which is easily soluble in sodium sulphite, forming addition products. 

Trinitro-m-xylene forms addition products less easily than a- trinitrotoluene. Undoubtedly the two methyl groups present in the ring reduce its ability to form addition compounds. 

With sodium- or potassium methoxide, trinitroanisole reacts like sym-trinitro-benzene or a- trinitrotoluene, viz. it adds on an alcoholate molecule, forming a red-coloured addition product (I) ... 

These reactions divide the three trinitrotoluenes into two distinct classes. Alpha trinitrotoluene constitutes the one class, in which one molecule of trinitrotoluene reacts with but one molecule of aniline or dimethylaniline while in the second class, one molecule of either the beta or gamma trinitrotoluenes reacts with three molecules of the base, forming decomposition products instead of one addition product. The property of forming addition products seems to hinge npon the symmetrical positions of the nitro-groups. 

The alpha dinitrotoluene will form addition products mth naphthalene and anthracene just as the alpha trinitrotoluene will do. The naphthalene product has the following formula. (12)... 

The product is now mixed with 2 1. of distilled water at 35° in a 5-I. flask provided with a stirrer, and 15 per cent sodium hydroxide solution is dropped in with continuous stirring until a faint red color is just produced. Should this disappear, it is restored by the addition of a few drops more. When it has persisted for five minutes, the color is discharged by the addition of a few drops of acetic acid, and the insoluble unattacked trinitrotoluene filtered off and washed with a little water. The trinitrobenzoic acid is precipitated from the filtrate by the... 

Electron-transfer-induced FQ is the most practical and efficient mechanism of signal transduction for the detection of explosives. This is because explosives, especially 2,4,6-trinitrotoluene (TNT), are often highly electron-deficient molecules that readily accept electrons from excited fluorophores. In addition, explosive devices that contain TNT also usually contain a synthetic by-product, 2,4-dinitrotoluene (DNT), which is also highly electron deficient. A basic frontier molecular orbital-based mechanism for electron transfer FQ is illustrated in Figure 3. 

From a practical point of view, reduction of NACs is of great interest for two reasons. First, the amino compounds formed may exhibit a considerable (eco)toxi-city, and therefore may be of even greater concern as compared to the parent compounds. Additionally, the reduced products may react further with natural matrices, in particular with natural organic matter, thus leading to bound residues (see sections on oxidations below). One prominent example involves the reduction products of the explosive, 2,4,6-trinitrotoluene (TNT see Fig. 14.6), particularly the two isomeric diaminonitrotoluenes (2,4-DA-6-NT and 2,6-DA-4-NT) and the completely reduced triaminotoluene (TAT). These have been found to bind irreversibly to organic matter constituents present in soils (Achtnich et al., 2000) and sediments (Elovitz and Weber, 1999). This process offers interesting perspectives for the treatment of NAC contaminated sites. In fact, a dual step anaerobic/aerobic soil slurry treatment process has been developed for remediation of TNT contaminated soils (Lenke et al., 2000). 

It has been established experimentally (T. Urbanski, Kwiatkowski, Miladowski [22]) that the addition to pentaerythritol tetranitrate of such nitro compounds as nitrobenzene, nitrotoluene, dinitrobenzene, dinitrotoluene, trinitrobenzene, and trinitrotoluene, decreases its stability as determined by heating to 120-135°C. The degree of decomposition of PETN, heated alone or in mixtures, can be estimated in terms of the pH-values determining the acidity of the decomposition products (Table 32, Fig. 72). 

Nitro compounds, particularly the higher nitrated derivatives, readily enter into nucleophilic reactions. The reactions of aromatic halogenonitro compounds with bases (p. 453), as well as the addition of potassium methoxylate on to sym-trini-trobenzene resulting in the formation of an anisole derivative will be discussed below. Similar addition reactions of potassium methoxylate to trinitrotoluene (p. 301) and trinitroanisole (p. 546) are also known. These reactions were described in detail by Meisenheimer [36-38], Confirmation of such an interpretation of the reaction is provided by the fact that in the reaction of potassium ethoxylate with trinitroanisole the same dark coloured product (I) is obtained, as when potassium methoxylate is reacted with trinitrophenetole ... 

However, trinitrotoluene reacts with alkalis, yielding organo-metallic products. The readiness of trinitrotoluene to react with alkalis has suggested the idea that it is an acid. This problem was studied by Fanner [75] in 1901. He applied a method, based on determining the partition coefficient K for trinitrotoluene between two liquid phases water and benzene or water and ligroin phase, with addition of sodium hydroxide to the water phase. 

Naoum [100] found that trinitrotoluene, when exposed to light, yields a product of the formula C14H8O10N5, insoluble in benzene or water, and exceptionally sensitive to impact. In addition, a water-soluble red dye is formed. 

Dissolve 100 grams of 2,4,6-trinitrotoluene into 200 milliliters of p-dioxane, and then place the mixture into a cold-water bath. Then stir the mixture, and add 2 milliliters of 28 - 30% ammonium solution. Then bubble 46 grams of hydrogen sulfide gas into the mixture over a 2-hour period while keeping the reaction temperature at 20 Celsius by means of the cold-water bath, and stir the reaction mixture continuously during the addition. After the addition of the hydrogen sulfide gas, filter off the precipitated sulfur, and then add the filtered reaction mixture to 1000 milliliters of ice water. After which, filter off the yellow precipitated solid, and then wash the solid with 400 milliliters of water. Then vacuum dry or air-dry the solid. The result is a mixture of the desired 4-amino-2,6-dinitrotoluene (61%), and the by-product, 4-hydroxylamino-2,6-dinitrotoluene (39%). 

Beta and gamma trinitrotoluenes react with aniline, but the product formed is not an additive compound... 

Alkalies produce addition, substitution, and condensation products. Alkalies and alkali compounds produce red colorations with alpha trinitrotoluene. Coparisow found that when 5 c.c. of a saturated solution of potassium hydroxide in methyl alcohol, cooled in solid carbon-dioxide-ether mixture, are added to. 166 g. of pure symmetrical trinitrotoluene, dissolved in a mixture of 1 c.c. pryidine and, 5 c.c. methyl alcohol the latter solution being kept cool in solid carbon-dioxide-ether mixture, the color change took place at a temperature as low as —65° C. 

Anhydrous sodium carbonate (30 g.) is added to a warm solution of 70 g. (0.31 mole) of 2,4,6-trinitrotoluene (Caution—-explosive substance) in 500 ml. of a mixture of equal volumes of ethanol and acetone. To the resulting mixture is added gradually (1 hour) with stirring 50 g. (0.33 mole) of p-nitrosodimethylaniline [Org. Syntheses Coll. Vol. 1, 214 (1941)]. The temperature of the reaction mixture is held below 50° during this period and for an additional hour of stirring, after which the mixture is allowed to stand for 24 hours. The solid product is removed by filtration and triturated with ethanol followed by filtration to remove the ethanol. The material is treated three times with ethanol and once with acetic acid in this manner and then is dried and powdered. (Caution—product is a dangerous explosive.)... 

Although many other explosives and explosives-related compounds exist, only the data for 2,4,6-trinitrotoluene (TNT) and its breakdown products, the cyclic nit-ramines (RDX and HMX), tetryl, trinitrobenzene, and nitroglycerin will be reviewed in this chapter. Two dinitrotoluene isomers are also included, as they are still used as explosives in addition to being side-products of TNT synthesis. 

You have to determine (a) formaldehyde and acetaldehyde in 50 samples of white wine per day (b) 2,4,6-trinitrotoluene in white powder samples which might be potential material in making bombs—3 to 5 samples per month (c) copper content in a rare Etruscan vase (d) a toxic keto compound in an antibiotic, the analysis being done in a production-line quality-control laboratory in a pharmaceutical company. In which cases and why would you use a standard-addition method and when would you use a calibration curve for evaluating current-versus-voltage curves ... 

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