High‐Density Energetic Mono‐ or Bis(Oxy)‐5‐Nitroiminotetrazoles

Abstract

Dedicated to Professor Malcolm M. Renfrew on the occasion of his 100th birthdayIn the last decade, the investigation of energetic tetrazolescyanotetrazole, aminotetrazole, azidotetrazole, nitrotetrazole, and nitroiminotetrazole-has led to major developments in the area of high-energetic materials by many research groups. [1] Several exciting classes of 5-substituted tetrazole moieties are introduced in the literature. [2] Tetrazoles can be protonated to form tetrazolium salts [3] or deprotonated to give tetrazolates. [4] While deprotonation increases the thermal stability of tetrazoles, protonation can lower the decomposition temperature. [5] These energetic materials based on high nitrogen content are derived from their high heats of formation due to the large number of NÀN and C À N bonds. [6] The combination of a tetrazole ring with energetic substituent groups containing oxygen atoms, such as nitro groups, nitrate esters, or nitramine, is of interest leading to excellent oxidizers. Current research issues in the field of high energetic materials include increasing oxygen content, which may result in the replacement of ammonium perchlorate in an effort to decrease pollution. Organic 5-nitrotetrazole derivatives, [1k, 7] especially for synthesis of the highly energetic 1-methyl-5-nitrotetrazole, were synthesized in good yields. These were calculated to be endothermic with heats of formation of 2.16 kJ g À1 , which was assessed by means of standard tests and quantum chemical calculations. [7] In addition, the highly energetic, nitrogen-rich 1-methyl-5-nitroiminotetrazole [8] and its salts [8c] can easily be obtained by nitration of aminotetrazole followed by metathesis reactions using silver 1-methyl-5-nitroiminotetrazolate and the guanidinium family of chlorides in aqueous solution with high yields. Although 5-nitroiminotetrazole derivatives and their salts are energetic materials with high nitrogen content, they show good stabilities towards friction and impact, and good thermal stability. [8c, 9] The development of new energetic compounds with similar attractive properties exhibit significant promise in optimizing environmentally benign replacements for toxic materials. [10] In the past few years, the most convenient route to 1substituted 5-aminotetrazole is the addition of amine or hydrazine to cyanogen azide, [11] which was found to be an efficient reagent for the synthesis of readily purified 1-substituted 5-aminotetrazoles from primary amines under non-catalytic mild conditions. Nitration of these aminotetrazoles using 100 % nitric acid has been shown to form mono-, di-, or tri-substituted nitroiminotetrazole derivatives. [12] With these features in mind, our group became interested in examining the analogous chemistry using alkoxy amine derivatives.Here we describe the work leading to a series of nitroiminotetrazole derivatives of oxy nitroiminotetrazoles and their salts, with potentially significant physical and energetic properties. The aim of our study was to elucidate the structures in the crysta...

New Application of Hydroxyl Groups: Ligands for High Density Metal Organic Frameworks

“…As show in Table 1, the density of (1) and (2) is 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 2.41 g cm À3 and 2.54 g cm À3 , respectively. The density of (1) and (2) is higher than that of the organic explosives TNT (1.65 g cm À3 ) and RDX (1.81 g cm À3 ) ( Table 1), but is also higher than that of the MOFs with the same ligands and metal ions reported to date (Figure 3), including [Cu(atz) 3 (NO 3 ) 2 ] n (1.811 g cm À3 ) [29], [Cu(atz) 2 (NO 3 ) 2 ] n (2.072 g cm À3 ) [26], Zn 2 (ata) 3 (1.68208 g cm À3 ) [27] and [Zn(ata) 2 (NO 3 )] n (2.12076 g cm À3 and CCDC: 1028765).…”

“…The solid was collected by filtration, washed with deionized water, and vacuum dried at 60 8C. Elemental analysis of CH 3…”

“…Development of superior energetic materials is becoming increasingly important in materials science research [1][2][3][4][5][6]. High-energy MOFs (HE-MOFs) which make use of high nitrogen content azole heterocycles and their derivatives as ligands are a unique class due to their interesting structures.…”

Synthesis, crystal structure and thermal behavior of a new 1D polymeric strontium complex with tetrazole-1-acetic acid

“…Tetrazole derivatives have attracted a great amount of attention in the field of heterocyclic chemistry due to their fascinating structures and interesting properties [1][2][3][4][5]. In recent years, the design and synthesis of tetrazole-based nitrogen-rich compounds have been of intense interest in the area of energetic materials [6][7][8][9][10][11][12][13][14]. Tetrazole compounds appear to demonstrate the best compromise between high performance, low sensitivity, and moderate thermal stability.…”

A novel compound [Mn(H2O)6](AMTZ)2(PA)2 (AMTZ = 4-amino-3,5-dimethyl-1,2,4-triazole and PA = Picrate) with Extensive hydrogen bonds: Synthesis, structure and thermal characters

“…Klapötke, Cudziło and others have studied nitrogen-rich energetic compounds containing imidazoles [4][5][6][7][8][9][10][11][12][13][14][15][16][17], triazoles [18][19][20][21], tetrazoles [22][23][24][25][26][27], tetrazines [28][29][30], and their derivatives [31,32].…”