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91.
Dr. Sevi Öz Ingrid Svoboda Raif Kurtaran Mecit Aksu Musa Sari Melike Kunduraci Orhan Atakol 《无机化学与普通化学杂志》2011,637(2):257-262
Nine CuII complexes ( I – IX ) containing the azide ion and bis‐2,6‐(pyrazol‐1‐yl)pyridine (pp), bis‐2,6‐(pyrazol‐1‐yl)pyridine (dmpp), and 2‐(pyrazol‐1‐yl)‐6‐(3,5‐dimethylpyrazol‐1‐yl)pyridine (mpp), which are derivatives of pyrazolylpyridine, were prepared in nonaqueous medium. These complexes were characterized by elemental analyses and IR spectroscopy. Crystals of one of these complexes [CumppClN3 ( VII )] were prepared in suitable size, and a molecular structure of this complex was obtained with X‐ray diffraction method. Complexes were examined by thermogravimetry and differential scanning calorimetry methods. Thermal decomposition was observed in complexes including two azide groups similar to that seen in explosives. In the complexes containing one azide group, formation of the CuI complexes was observed after thermal decomposition of the azide group. 相似文献
92.
Jinhong Song Prof. Dr. Zhiming Zhou Dan Cao Haifeng Huang Lixuan Liang Kai Wang Jun Zhang 《无机化学与普通化学杂志》2012,638(5):811-820
Energetic salts that contain nitrogen‐rich cations and the 2‐(dinitromethyl)‐3‐nitro‐1, 3‐diazacyclopent‐1‐ene anion were synthesized in high yield by direct neutralization reactions. The resulting salts were fully characterized by multinuclear NMR spectroscopy (1H and 13C), vibrational spectroscopy (IR), elemental analysis, density and differential scanning calorimetry (DSC), and elemental analysis. Additionally, the structures of the ammonium ( 1 ) and isopropylideneaminoguanidinium ( 9 ) 2‐(dinitromethyl)‐3‐nitro‐1, 3‐diazacyclopent‐l‐ene salts were confirmed by single‐crystal X‐ray diffraction. Solid‐state 15N NMR spectroscopy was used as an effective technique to further determine the structure of some of the products. The densities of the energetic salts paired with organic cations fell between 1.50 and 1.79 g · cm–3 as measured by a gas pycnometer. Based on the measured densities and calculated heats of formation, detonation pressures and velocities were calculated using Explo 5.05 and found to to be 25.2–35.5 GPa and 7949–9004 m · s–1, respectively, which make them competitive energetic materials. 相似文献
93.
A straightforward way for the preparation of the energetic 5‐aminotetrazolium and 1, 5‐diaminotetrazolium salts is reported. The energetic salts were readily synthesized by the reaction of 5‐aminotetrazolium nitrate or 1, 5‐diaminotetrazolium nitrate with ammonium 5‐nitroiminotetrazolate, ammonium 1‐methyl‐5‐nitroiminotetrazolate, bis(ammonium) ethylene bis(5‐nitroiminotetrazolate), and diammonium iminobis(5‐tetrazolate), respectively, in water under mild conditions. All products were recovered as highly crystalline materials in excellent yields and purities, and were fully characterized by IR spectroscopy, 1H and 13C NMR spectroscopy, DSC measurements as well as elemental analyses. 相似文献
94.
The energetic boron esters tris(1‐ethyl‐5‐aminotetrazolyl) borate, tris(2‐ethyl‐5‐aminotetrazolyl) borate, tris(1‐ethyltetrazolyl) borate, tris(2‐ethyltetrazolyl) borate, and tris(2‐(3‐nitro‐1, 2,4‐triazolyl)ethyl) borate were synthesized and analyzed by NMR and IR spectroscopy, elemental analysis, and mass spectrometry. Two tetracoordinate borates potassium tetrakis(3‐nitro‐1, 2,4‐triazolyl)borate and potassium bis(4, 4′,5, 5′‐tetranitro‐2, 2′‐bisimidazolyl)borate were synthesized and fully characterized as well. Moreover, the energetic and thermal properties of the energetic boron esters and tetracoordinate borates were determined. The 11B NMR chemical shifts of potassium tetrakis(3‐nitro‐1, 2,4‐triazolyl)borate and potassium bis(4, 4′,5, 5′‐tetranitro‐2, 2′‐bisimidazolyl)borate were calculated and compared to the experimental values. Tris(1‐ethyl‐5‐aminotetrazolyl) borate was tested as colorant in pyrotechnic formulations with respect to the combustion behavior and color properties as well as the energetic and thermal properties. 相似文献
95.
Furazan and furoxan represent fascinating explosophoric units with intriguing structures and unique properties. Compared with other nitrogen-rich heterocycles, most poly furazan and furoxan-based heterocycles demonstrate superior energetic performances due to the higher enthalpy of formation and density levels. A large variety of advanced energetic materials have been achieved based on the combination of furazan and furoxan moieties with different kinds of linkers and this review provides an overview of the development of energetic poly furazan and furoxan structures during the past decades, with their physical properties and detonation characteristics summarized and compared with traditional energetic materials. Various synthetic strategies towards these compact energetic structures are highlighted by covering the most important cyclization methods for construction of the hetercyclic scaffolds and the following modifications such as nitrations and oxidations. Given the synthetic availabilities and outstanding properties, energetic materials based on poly furazan and furoxan structures are undoubtedly listed as a promising candidate for the development of new-generation explosives, propellants and pyrotechnics. 相似文献
96.
Nikita E. Leonov;Michael S. Klenov;Oleg V. Anikin;Aleksandr M. Churakov;Yurii A. Strelenko;Konstantin A. Monogarov;Vladimir A. Tartakovsky; 《European journal of organic chemistry》2019,2019(1):91-94
The first aliphatic nitro-NNO-azoxy compounds were synthesized by substitutive nitration of appropriate tert-butyl-NNO-azoxy compounds with nitronium tetrafluoroborate. Nitro(nitro-NNO-azoxy)methane (1), (tert-butyl-NNO-azoxy)(nitro-NNO-azoxy)methane (2), bis(nitro-NNO-azoxy)methane (3), and 2-nitro-2-(nitro-NNO-azoxy)propane (4) were prepared. Compound 4 with the nitro-NNO-azoxy group bound with the tertiary C atom appeared most stable (DSC, onset temperature of decomposition 104 °C). Compound 2 was less stable (DSC, onset temperature 88 °C). Compounds with strong electron withdrawing substituents had the least stability, assumingly, due to rather high acidity of CH protons alongside with instability of C-anions of nitro-NNO-azoxy compounds. 相似文献
97.
Haifeng Huang;Yameng Shi;Yao Yu;Jun Yang; 《European journal of organic chemistry》2018,2018(1):113-119
A series of energetic salts based on the 1,1,3,3-tetranitropropane-1,3-diide (TNP) dianion have been prepared and fully characterized by NMR and IR spectroscopy, elemental analysis, and single-crystal X-ray diffraction. Their thermal stability (Td = 111.0–180.9 °C) and sensitivities to mechanical stimuli (IS = 2–5 J; FS = 80–128 N) have been measured. Additionally, their heats of formation (–369.8 to 347.1 kJ mol–1) and detonation performances (P = 25.0–37.0 GPa; vD = 7675–9104 m s–1) have been calculated. 相似文献
98.
Ivan Gospodinov;Thomas M. Klapötke;Jörg Stierstorfer; 《European journal of organic chemistry》2018,2018(8):1004-1010
The synthesis of 3,5-diamino-4,6-dinitropyridazine-1-oxide (8) is reported. It is prepared in a six-step synthetic procedure starting from acyclic compounds, and shows good properties (detonation velocity DC–J = 8486 m s–1, detonation pressure pC–J = 302 kbar), and sensitivity toward mechanical stimuli. Compound 8 and its precursor (7, 3,5-dimethoxy-4,6-dinitropyridazine-1-oxide) were characterized by means of multinuclear (1H, 13C, 14N, 15N) NMR spectroscopy, mass spectrometry, vibrational spectroscopy (IR and Raman), elemental analysis and differential thermal analysis (DTA) measurements. Compounds 4, 5, 6, 7, 8 and 9 were also characterized by low-temperature single-crystal X-ray diffraction. The heats of formation for 7 and 8 were calculated using the atomization method based on CBS-4M enthalpies. Using the experimentally determined (X-ray) densities and the calculated standard molar enthalpies of formation, several detonation parameters such as the detonation pressure, energy and velocity were predicted by using the EXPLO5 code (V6.03). The sensitivities of 3,5-dimethoxy-4,6-dinitropyridazine-1-oxide (7) and 3,5-diamino-4,6-dinitropyridazine-1-oxide (8) toward impact, friction and electrical discharge were tested according to BAM standards. In addition, the shock reactivity of 8 was measured by applying the small-scale shock reactivity test, showing similar values to HNS, PYX and TKX-55. 相似文献
99.
Sodium and potassium methyl(nitroso)amide (M[CH3N2O], M = Na ( 1 ), K ( 2 )) were prepared by the reaction of monomethylhydrazine with iso‐pentyl nitrite or n‐butyl nitrite and a suitable metal ethoxide (M[CH3CH2O], M = Na, K) in an ethanol‐ether mixture. The reaction of monomethylhydrazine with a small excess of iso‐pentyl nitrite or n‐butyl nitrite and in the absence of a metal ethoxide led to the formation of N‐nitroso‐N‐methylhydrazine (CH3(NO)N–NH2, ( 3 )). Alternatively, compound 3 was prepared by the amination reaction of 1 or 2 using the sodium salt of HOSA in ethanol solution. Compounds 1–3 were characterized using elemental analysis, differential scanning calorimetry, mass spectrometry, vibrational (infrared and Raman) and UV spectroscopy and multinuclear (1H, 13C and 15N) NMR spectroscopy. For compounds 1–3 , several physical and chemical properties of interest and sensitivity data were measured and for compound 3 thermodynamic and explosive properties are also given. Additionally, the solid‐state structure of compound 3 was determined by single‐crystal X‐ray analysis and the structures of the cis‐ and trans‐[CH3N2O]– anions and that of 3 were optimized using DFT calculations and used to calculate the NBO charges. 相似文献
100.
Gregory Drake Greg Kaplan Leslie Hall Tommy Hawkins Joann Larue 《Journal of chemical crystallography》2007,37(1):15-23
A new class of energetic ionic liquids based upon 1-amino-3-alkyl-1,2,3-triazolium nitrates (alkyl = methyl, ethyl, n-propyl, 2-propenyl, and n-butyl) has been synthesized and characterized by vibrational spectra, multinuclear NMR, elemental as well as contaminant
analyses, and DSC studies. A single crystal X-ray study was carried out for 1-amino-3-methyl-1,2,3-triazolium nitrate and
the details will be presented. 相似文献