Tetryl nitration

MC found primarily at impact areas and tiring lines of U.S. military testing and training ranges often consist of mixtures of residues from several MC. These may include the nitroaromatic explosive compounds 2,4,6-trinitrotoluene (TNT), 2,4- and 2,6-dinitro-toluene (DNT), and trinitrophenylmethylnitramine (tetryl) nitrate esters such as nitrocellulose (NC), pentaerythritol tetranitrate (PETN), and nitroglycerin (NG) and the nitramine compounds, hexahydro-l,3,5-trinitro-l,3,5-triazine (RDX) and octahydro-l,3,5,7-tetranitro-l,3,5,7-tetrazocine (HMX). Most of these MC have been in use for decades, either as primary or secondary explosives or in propellant compositions. 

It is prepd by the action of methylamine on 4-chloro-l-nitrobenzene (Ref 5) by the action of methyl iodide (Ref 6), or methyl sulfate on 4-nit roaniline (Ref 7) or by the hydrolysis of 4-nitro-N-methylformanilide with hot coned aq HC1 (Ref 8). In a study of the effect of nitric acid concn on the prods of the nitration of N,N-dimethylaniline to form Tetryl, it was isolated in low yield by the action of nitric acid, d 1.046g/cc, plus Na nitrite on N,N-dimethylaniline (Ref 10). A eutectic mixt with N-ethyl-4-nitroaniline has been patented as a stabilizer for NC (Ref 12). Studies at NPF indicate that 4-nitro-N-methyl-aniline is superior to Centralite, 2-nitrodiphenyl-amine, or Acardite in stabilizing. NC Refs 1) Beil 12, 586, (295) 1125 ... 

Registry No 19092-03-6. It has been shown to be an intermediate in the prepn of Tetryl from N,N-dimethylaniline as it can be prepd from N,N-dimethylariiline or 2,4-dinitro-N-methylaniline by the action of 70% nitric acid in 90% yield (Refs 13 14) and can be nitrated to Tetryl with a mixt of 64% sulfuric acid, 15% nitric. acid, and-21%-w yield 91.9% (Ref 14). It can be isolated from commercial Tetryl and identified by thin layer chromatography (Ref 21) N,2,6-Trinitro-N-methylaniline (2,6-dinitrophenyl-methylnitramine), mp 110.8 874.9kcal/... 

Nitroisobutylglycol dinitrate). CH3.C.N02(CH20N02)2, mw 225.14, N 18.67%, OB to C02 —24.87%, mp 38°, ignites above 240°. Prepd from the glycol by nitration with mixed acid, with 90% yield. Brisance, crushes 53g sand, equivalent to Tetryl. Qc is 531.4cal/mole. Impact sensitivity, FI 86% relative to PA, with Bruceton No 5 machine,... 

The resulting N-methyldinitrotoluidines, when further nitrated, yield methyl Tetryl. Methyl Tetryl is a less powerful expi than Tetryl, and has not been used commercially ... 

Tetryl. In the manufacture of Tetryl, it is usual not to nitrate dime thy laniline directly, but to dissolve it first in coned sulfuric acid and then to nitrate the dimethylaniline sulfate so obtained. Direct nitration of dimethylaniline proceeds so violently that it can be carried out only under specialized conditions. Many years experience of Tetryl manufacture has shown that the ratio of sulfuric acid to dimethylaniline should not be lower than 3 1, since a smaller amount of sulfuric acid may be detrimental to the nitration process. However, the ratio of sulfuric acid to dimethylaniline must not be too high, otherwise Tetryl yield is decreased. Temp must be maintained between 20-45° to avoid sulfonation of the benzene ring. Care must be exercised not to leave any unreacted dimethylaniline prior to introduction of nitric acid, because of the potential violence of the dimethyl-aniline-nitric acid reaction. Consequently, continuous methods of prepn are to be preferred as they inherently minimize accumulation of unreacted dimethylaniline... 

Nonaqueous titrimetry has been applied to detn the purity of inorganic stearates, nitrates, RDX, Aram Picrate, Tetryl, Haleite, TNG, K nitrate in M-8 propint and NGu (See Vol 1, A165-R Vol 3, D102-L C625-R to C626-L Vol 6, G154-L G161 Refs 30, 30a, 30b, 30c, 30d, 30c, 30f, 30g, 36, 59 61)... 

Phenyl ethyleneglycol Nitrated Products. Nitration of phenylethyleneglycol with mixed nitric-sulfuric acid gave an expl product, mp ca 85°, which was claimed to be 110% as powerful as TNT, as detd by the Trauzl test, and whose performance was intermediate between that of Tetryl and TNT (Ref 1)... 

More recently methylamine is treated with 2, 4- or 2, 6-dinitrochlorobenzene (usually in the form of an unseparated mixture of isomers) to give dinitrophenylmethylamine. This without separation is then nitrated to tetryl. 

Durgapal, U. C. et al., Propellants, Explosives, Pyrotechnics, 1995, 20, 64 This compound, made by mild nitration of polyvinyl alcohol, is an explosive as shock sensitive as tetryl. 

The chemical structures of some common mifttary explosives are shown in Figure 1. These include the nitrate esters such as nitrocellulose (NC), NG, EGDN, and (PETN) nitroarenes such as trinitrotoluene (TNT, CH3—C6H2(N02)3), picric acid (HO—C5H2(N02)3), and 2,4,6-trinitrophenylmethylnitramine (tetryl) and nitramines such as RDX (C3H6N6O6), HMX (C4H8N8O8), and hexanitrohexa-azaisowurtzitane (CL— 20). Of these, only CL— 20 is new , that is, less than 50 years old [3]. Mixtures of oxidizers and fuels, such as AN and FO (called ANFO), are also secondary explosives. 

Alkahne hydrolysis, followed hy the use of sulfanihc acid and 1-naphtylamine, was the basis of a spot test for NG [37], as well as for several nitrate esters and nitramines, including NG, NC, tetryl, and RDX [38]. It is also a common spray for the detection of nitrate esters and nitramines on TLC plates [25, 29, 37, 39—41]. 

Nitrations of aromatic amines often involve the intermediate formation of N-nitramines, although these are rarely seen under the strongly acidic conditions of mixed acid nitration (Section 4.5). N,2,4,6-Tetranitro-N-methylaniline (tetryl) is an important secondary high explosive usually synthesized from the nitration of N,N-dimethylaniline or 2,4-dinitro-N-methylaniline. ° The synthesis of tetryl is discussed in Section 5.14. 

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 number of important explosives contain nitramino functionality in conjunction with nitrate ester or C-nitro functionality. A-Nitrodiethanolamine dinitrate (DINA) (7) is a powerful explosive which can be melt-cast into charges. A,2,4,6-Tetranitro-A-methylaniline (tetryl) (8) exhibits high brisance (VOD 7920 m/s, d = 1.73 g/cm ) and has found application in both detonators and boosters, in addition to being a component of some composite high explosives. 

Tetryl (8) can be prepared from the nitration-oxidation of A, A-dimethylaniline (90) with a variety of nitrating agents and conditions, including the use of a large excess of 70 % nitric... 

Tetryl (8) can be synthesized in two steps from 2,4-dinitrochlorobenzene (231). Thus, reaction of the latter with methylamine under aqueous conditions yields 2,4-dinitro-lV-methylaniline (228), which readily undergoes nitration to tetryl (8) on treatment with mixed... 

Kinetics of isothermal decompn of K perchlorate) 3) Inst of Study of Rate Processes, Univ of Utah, "The Isothermal Decomposition of Tetryl and Hydrazine Nitrate , TechRept No XL111 (Dec 1954) Contract N7-onr-45107 4) R.M. 

K chlorate PA Pb nitrate Tetryl and Pb nitride TNT) 22-3 (Nature of priming compositions) 23-5 (Primer composition materials) 25 (Sampling of primer materials) 25 (Identification of primer materials) ... 

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