1,3-Nitramine nitrates

The use of oxetanes for the synthesis of polynitrate esters is generally of less value than the use of epoxides, which are readily available from the epoxidation of alkenes. The analogous reaction of azetidines with dinitrogen pentoxide is a route to 1,3-nitramine-nitrates and these reactions are discussed in Section 5.8.2. ... 

A-Picrylazetidine (155) is found to be inert to attack by dinitrogen pentoxide, a consequence of the electron-withdrawing picryl group. The triazine (156) gave a 60 % crude yield of the energetic 1,3-nitramine-nitrate (157) which is an analogue of Tris-X. 

The reaction of aziridines and azetidine heterocycles with dinitrogen pentoxide in chlorinated solvents yields 1,2-nitramine nitrates and 1,3-nitramine nitrates respectively. In most cases yields are good to excellent, but, reactions are not as general as with the oxygen heterocycles the outcome of reactions is heavily dependent on the nature of the substituent on the exocyclic nitrogen. Some of the products from these reactions find use as melt-castable explosives i.e. Tris-X (46) and energetic plasticizers e.g. Bu-NENA (48) the latter is a component of some LOVA (low vulnerability ammunition) propellant formulations. 

The anhydride of nitric acid, N20, reacts with 2-methyl aziridine to give the dinitrate (105). In the case of A/-substituted aziridines, the reaction stops at the stage of the nitramine nitrate prior to elimination of N2O (106). 

At best, expl power i a somewhat nebulous quantity. If we consider relative power as measured in a Ballistic Mortar or Trauzl Block, then OB correlates reasonably well with relative power, provided these comparisons are made for similar expls. This is illustrated in Fig 1, where Ballistic Mortar measurements axe respectively correlated with OB for nitro, nitramine, nitrate ester and aluminized expls. In general Ballistic Mortar measurements are more reproducible than Trauzl Block data. Consequently we have shown these in preference to Trauzl Block measurements. Correlation between Trauzl block data and OB are reported in Refs 1 8... 

A number of nitramine-nitrate explosives have been prepared by Millar and co-workers from the action of dinitrogen pentoxide on aziridines and azetidines (Section 5.8). Millar and co-workers used their aziridine ring-opening nitration methodology (Section 5.8.1) to synthesize the high performance melt-castable nitramine-nitrate explosive known as Tris-X... 

Millar and co-workers studied the reaction of dinitrogen pentoxide in chlorinated solvents with a number of different A-substituted aziridines and found that reactions are highly dependent on the nature of the A-substituent on the aziridine nitrogen (Table 5.9). A-Alkylaziridines give good yields of 1,2-nitramine-nitrate product (Table 5.9, Entry 1). These... 

Nitramine-nitrates from the reaction of aziridines with dinitrogen pentoxide (ref. 124)... 

The order and timing of the addition of reagents in the KA-process is varied but in a typical procedure three reagents, namely, acetic anhydride, a solution of ammonium nitrate in nitric acid, and solid hexamine dinitrate, are added slowly, in small portions and in parallel, into the reaction vessel which is preheated to 60-80 °C. On completion the reaction mixture is often cooled to 50-60 °C and the RDX filtered and sometimes washed with acetic acid. This process produces a product which melts over a 2 °C range but the RDX still contains up to 10 % HMX as a by-product. Dilution of the reaction mixture with water before removing the RDX produces a very impure product containing numerous unstable linear nitramine-nitrates. Based on the assumption that one mole of hexamine dinitrate produces two mole of RDX the KA-process commonly yields 75-80 % of RDX. 

Nitramine-nitrates of general structure (133) are known as NENAs and are conveniently prepared from the nitrative cleavage of A-alkylaziridines " with dinitrogen pentoxide or from the direct nitration of the corresponding aminoalcohols. These compounds find use as energetic plastisizers in explosive and propellant formulations Bu-NENA (R = n-Bu) is a component of some LOVA (low vulnerability ammunition) propellants. ... 

The 1,2-nitramine-nitrate Tris-X (189) (VOD 8700 m/s, m.p. 69 °C)has been synthesized from the reaction of 2,4,6-tris(aziridino)-l,3,5-triazine (188) with dinitrogen pentoxide in chloroform or methylene chloride at subambient temperature (Section 5.8.1). °... 

Aziridines and azetidines react similarly, giving nitramine nitrates e.g., N-butylazetidine gave N02OCH2CH2CH2N(Bu)N02.736... 

See 2,4,6-Trinitrophenyl-(l-methylol)propyl-nitramine Nitrate] 7)A.D.Little,Inc, Report on Study of Pure Explosive Compound, Cambridge,Mass,.v 4(1952) Compd No 305, p 586(Part of rept is unclassified)... 

TrinitrophenylaminoybiaanoU N-nitramine Nitrate McGill(Ref 4) 2,4.6-Trinitrophenylisobutylolnitramine Nitrate and Blatt(Ref 6) 2l4,6 Trinitropbenyl (l methyloiypTopylnitramme Nitrate. 

OSRD Rept 4134(1944) (Nitramine-nitrates from aminoalcohols) i)J.(3arbidre,BullFr[5], 11,470-80... 

This change in editorial leadership has resulted, perhaps inevitably, in a change in editorial policy which is reflected in the contents of Volume 8. there has been a marked de-emphasis on the inclusion of organic parent compounds followed by an exhaustive and voluminous cataloging of azide, azido, azo, diazido, diazonium, diazo, nitro, dinitro, polynitro, nitramine, nitrate (esters and salts), dinitrate, polynitrate, nitroso, polynitroso, chlorate, perchlorate, peroxide, picrate, etc, derivatives - regardless of whether any of these derivatives exhibit documented explosive or energetic properties. Only those materials having such properties have been included in this volume... 

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