2.4.6- Trinitrotoluene, hydrolysis

Another concern for polystyrene- and some aromatic-based PEMs is hydrolysis of fhe sulfonic acid group from aromatic rings as well as hydrolytic cleavage of polymer backbone under fuel cell conditions for aromafic polymers including polyimides, poly(arylene ethers), poly(ether ketones), and poly(ether sulfones). It is well known that the sulfonation of aromafic rings is a reversible process especially at low pH and at elevated temperature (Scheme 3.3). The reversibility of sulfonation, for example, is used in fhe preparafion of trinitrotoluene or picric acid. Por the simplest membrane of the class of arylsulfonic acids (i.e., benzenesulfonic acid), fhe reacfion occurs upon freatment with a stream of superheated steam at 180°C.i ... 

Mills A, Seth A, and Peters G, Alkaline hydrolysis of trinitrotoluene, TNT, Phys. Chem. Chem. Phys., 5, 3921, 2003. 

Emmrich M, Kinetics of the alkaline hydrolysis of 2,4,6-trinitrotoluene in aqueous solution and highly contaminated soils, Environ. Sci. Technol., 33, 3802, 1999. 

The classical Vilsmeier-Haack reaction - involves electrophilic substitution of a suitable carbon nucleophile with a chloromethyleneiminium salt, for example salt (1). Suitable carbon nucleophiles are generally electron-rich aromatic compounds such as V,N-dimethylaniline (2), alkene derivatives such as styrene (3) or activated methyl or methylene compounds such as 2,4,6-trinitrotoluene (4 Scheme I). These compounds (2-4) react with salt (1) giving, after loss of hydrogen chloride, the corresponding im-inium salts (5-7). Hydrolysis of iminium salt (5) affords aldehyde derivative (8) and this transformation (Ar—H - Ar—CHO) is the well-known Vilsmeier-Haack formylation reaction. Hydrolysis of iminium... 

While no new synthetic methods for this group have appeared improvements in the synthesis of phloroglucinol and that of some of its derivatives have attracted attention. The classic route by way of trinitrotoluene, trinitrobenzoic acid, triaminobenzoic acid and its hydrolysis and decarboxylation has been challenged by methods based on the use of acyclic precursors. 

General Finding 3. The conditions under which aromatic nitro compounds, such as trinitrotoluene (TNT) or picric acid, will emulsify in the aqueous phase and not be completely hydrolyzed are not well understood. Therefore, this type of material could be present in the output stream from an energetic hydrolysis step. 

The reaction of l,2-dichloro-4,5-dinitrobenzene with dilute aqueous sodium hydroxide results in substitution of a nitro-group by hydroxide. However, in hydroxide concentrations greater than 2 mol-dm", only the formation of monohydroxy- and dihydroxy-adducts (42) is observed, and acidification yields the original reactant. The cyanide adduct (43) of 1,3,5-trinitrobenzene has been observed by electrospray ionization mass spectrometry, using acetonitrile as the cyanide source. X-ray structures of the stable crystalline adducts formed from 4,6-dinitrobenzofiiroxan and dodecyl- and hexadecyl-amine have been reported. There has also been a report, related to the destruction of energetic materials, of Meisenheimer complex formation during the alkaline hydrolysis of 2,4,6-trinitrotoluene and 2,4-dinitroanisole. ... 

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