2,4,6-Trinitroaniline

The phenomenon has also been observed in the AT-nitration of iV-methyl-2,4,6-trinitroaniline and the O-nitration of alcohols. ... 

Another circumstance which could change the most commonly observed characteristics of the two-stage process of substitution has already been mentioned it is that in which the step in which the proton is lost is retarded because of a low concentration of base. Such an effect has not been observed in aromatic nitration ( 6.2.2), but it is interesting to note that it occurs in A -nitration. The A -nitration of A -methyl-2,4,6-trinitroaniline does not show a deuterium isotope effect in dilute sulphuric acid but does so in more concentrated solutions (> 60 % sulphuric acid kjj/kjj = 4 8). ... 

Fig. 1.11 Dissociation ranges of colour indicators for determination of the acidity function H0 in H2S04-H20 mixtures (1) p-nitroaniline, (2) o-nitroaniline, (3) p-chloro-o-nitroaniline, (4) p-nitrodiphenylamine, (5) 2,4-dichloro-6-nitroaniline, (6) p-nitroazobenzene, (7) 2,6-dinitro-4-methylaniline, (8) benzalacetophenone, (9) 6-bromo-2,4-dinitroaniline, (10) anthraquinone, (11) 2,4,6-trinitroaniline. (According to L. P. Hammett and A. J. Deyrup)...

This salt of the ac/-o-iminoquinonoid form of 2,4,6-trinitroaniline explodes violently at 110°C. 

In general the method is not as useful for the preparation of arylamines as for aliphatic amines. But the method becomes of preparative interest when the nuclear halogenated compound contains in addition some electron withdrawing substituents e.g., -N02, -CN etc. in ortho and para positions. Thus, 2, 4, 6 trinitroaniline (picramide) is readily prepared by the action of aqueous ammonia on... 

Formal sequential addition of amino groups to 2,4,6-trinitroaniline gives 1,3-diamino-2,4,6-trinitrobenzene (DATB, 56) and 1,3,5-triamino-2,4,6-trinitrobenzene (TATB, 57). TATB is more stable than expected from the additivity calculation. The ability to have hydrogen bonding with three amino groups both intra- and inter-molecularly in the crystal stabilizes the molecule. The molecule that results is thermally stable and used as an explosive in situations where a very insensitive explosive is needed. 

The same displacement occurs in the hydrolysis of picrylimidazole238 (103). 103 reacts with n-butylamine in water239 to yield picric acid (from the reaction with water) and N-n-butyl-2,4,6-trinitroaniline. The dependence of k0bs values (s 1 moP1 dm3) on pH values indicates the presence (and importance) of equilibrium 27 on the reaction pathway of the... 

Solutions of sodium or potassium nitrates in concentrated sulfuric acid can be used as a substitute for anhydrous mixed acid." 2,4,6-Trinitroaniline (picramide) has been synthesized via the addition of a solution of potassium nitrate in concentrated sulfuric acid to a solution of either o- or p-acetanilide in oleum. ... 

Nielsen and co-workers studied the oxidation of arylhydroxylamines and their O-methyl derivatives with ozone in inert solvents at subambient temperature. 1,2,3,5-Tetranitrobenzene (54) is formed in quantitative yield from the oxidation of both N-hydroxy-2,4,6-trinitroaniline... 

The presence of three nitro groups on the aromatic ring of picryl chloride makes the chloro group extremely reactive towards nucleophiles. Picryl chloride (87) is hydrolyzed to picric acid (4) in the presence of hot water or aqueous sodium hydroxide. Aminolysis of picryl chloride in the presence of primary and secondary amines is complete in minutes at room temperature. Picryl chloride is therefore a very useful starting material for the synthesis of a range of other picryl derivatives. The reaction of picryl chloride (87) with ammonia can be used to synthesize 2,4,6-trinitroaniline (53) (picramide). Treatment of picryl chloride with alcohols under reflux forms picric acid and the alkyl chloride of the corresponding alcohol, whereas the same reaction in the presence of alkali metal hydroxides, or the alkoxide anion of... 

Picryl chloride (87) reacts with hydroxylamine hydrochloride to yield 2,4,6-trinitroaniline (53) (picramide) and not the expected At-hydroxy-2,4,6-trinitroaniline. In contrast, the same reaction in the presence of sodium ethoxide is reported to yield 4,6-dinitrobenzofuroxan (94) via substitution of the halogen by hydroxylamine, followed by an internal redox reaction between the hydroxyamino group and one of the adjacent o-nitro groups. ... 

Other explosives, such as 2,4,6-trinitroanisole (7),33b.226 2,4,6-trinitroaniline (picramide), and tetryl (101), ° are conveniently prepared from the nitration of the corresponding 2,4-dinitro derivatives, which in turn, are prepared from the reaction of 2,4-dinitrochlorobenzene with the appropriate nucleophile. 

A,A -Bis(3-aminopicryl)-l,2-ethanediamine (108) (m.p. 275 °C) is prepared from the reaction of ethylenediamine with two equivalents of 3-chloro-2,4,6-trinitroaniline. " The same chemists reported 3,3 -diamino-2,2 4,4, 6,6 -hexanitrodiphenylamine (109), a heat resistant explosive (m.p. 232-237 °C) prepared from the reaction of l,3-dichloro-4,6-dinitrobenzene with 3-chloroaniline followed by mixed acid nitration and subsequent chloro group displacement with ammonia. The potassium salt of 3,3 -diamino-2,2, 4,4, 6,6 -hexanitrodiphenylamine shows very high thermal stability. " ... 

Orlova and co-workers "i reacted 1,2,3,5-tetranitrobenzene with hydrochloric and hydro-bromic acids to form picryl chloride and picryl bromide respectively. The same chemists treated 2,3,4,6-tetranitroaniline and 2,3,4,6-tetranitrophenol (121) with aqueous solutions of hydrogen halides to form 3-halo-2,4,6-trinitroanilines and 3-halo-2,4,6-trinitrophenols (122 and 123) respectively. 

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