Energetic Ionic Liquids from Azido Derivatives of 1,2,4‐Triazole

Abstract

Energetic ionic liquids with good thermal stabilities, relatively high densities, and high, positive heats of formation are described. Quaternization of azidoalkyl‐substituted 1,2,4‐triazoles with 4,5‐dinitroimidazole or 5‐nitrotetrazole (see Figure) result in room‐temperature liquids that may be useful in energetic materials/propellant applications.

Stickstoffreiche energetische Salze und ionische Flüssigkeiten

“…4,5-Dinitroimidazolat oder 5-Nitrotetrazolat) führt zur Bildung von energetischen Salzen. [30,34] Verschiedene energetische Salze von Azido-1,2,4-triazolium-Derivaten (11 a-d, Schema 3) [30] ließen sich durch Quaternisieren mit konzentrierter Salpeter-oder Perchlorsäure in Methanol in hoher Ausbeute leicht erhalten. Unter ähnlichen Bedingungen reagierte 1-Methyl-3-azido-1,2,4-triazol mit konzentrierter Salpeter-oder Perchlorsäure zu 1-Methyl-3-azido-1,2,4-triazoliumnitrat (12 a) bzw.…”

Structures and Energetic Properties of Two New Salts Comprising the 5,5'-Azotetrazolate Dianion

“…The central N=N distance in the azotetrazolate dianion is 1.2601(18) Å. Like many previously reported azolium azotetrazolate salts [23][24][25][26][27][28][29][30][31][32], the crystal structure of 2 is characterized by layers interconnected through an array of hydrogen bonds. Figure 8 shows a packing diagram of compound 2.…”

“…After short reaction times, bright yellow crystals of 2 ( Figure 6) formed in 86% isolated yield. was due to the asymmetric C-N=N stretching vibration of the azotetrazolate dianion [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33]. Bands in the range of 3127 cm are typical for the NH bonds in the 1H-1,2,4-triazole-1-carboxamidine cation.…”

“…Both the 1 H and 13 C NMR spectra were in good agreement with the expected structure. For example, the 1 H NMR spectrum showed a multiplet at δ 7.95 ppm for the phenyl hydrogens in para-position and a broad multiplet at δ 7.83-7.67 ppm can be assigned to the asymmetric N-C=N stretching vibration of the tetrazole ring, while a strong band at 724 cm −1 is characteristic for the asymmetric C-N=N stretching vibration of the azotetrazolate dianion [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33].…”

Synthesis and Crystal Structures of New 5,5'-Azotetrazolates

“…These salts typically contain cations such as hydrazinium [3][4][5], ammonium and guanidinium [6], triazolium [7][8][9][10], tetrazolium [11,12], or tetraaminopiperazinium [13], sometimes involving additional azido groups [6,10]. Preferred anions are-beside azide, nitrate, perchlorate and picrate-dinitramide [7], nitroazolates [7,10,14,15], dianions such as 5,5'-bis(tetrazolate) [16] and, in OPEN ACCESS particular, 5,5'-azotetrazolate [3][4][5][6]11,12,16]. The synthesis of 5,5'-azotetrazolates was first reported by Thiele [17].…”