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1.
Within this contribution on bis(oxadiazoles) we report on bis‐hydroxylammonium 5,5′‐dinitro‐methyl‐3,3′‐bis(1,2,4‐oxadiazolate), which (to the best of our knowledge) shows the highest density (2.00 g cm?3 at 92 K, 1.95 g cm?3 at RT) ever reported for an ionic CHNO explosive. Also the corresponding bis(ammonium) salt shows an outstanding density of 1.95 g cm?3 (173 K). The reaction of the 3,3′‐bis(1,2,4‐oxadiazolyl)‐5,5′‐bis(2,2′‐dinitro)‐diacetic acid diethyl ester with different nitrogen‐rich bases, such as ammonia, hydrazine, hydroxylamine, and triaminoguanidine causes decarboxylation followed by the formation of the corresponding salts (cation/anion stoichiometry 2:1). The reactions are performed at ambient temperature in H2O/MeOH mixtures and furnish qualitatively pure products showing characteristics of typical secondary explosives. The obtained compounds were characterized by multinuclear NMR spectroscopy, IR and Raman spectroscopy, as well as mass spectrometry. Single‐crystal X‐ray diffraction studies were performed and the structures of all compounds were determined at low temperatures. The thermal stability was measured by differential scanning calorimetry (DSC). The sensitivities were explored by using the BAM drophammer and friction test. The heats of formation were calculated by the atomization method based on CBS‐4M enthalpies. With these values and the X‐ray densities, several detonation parameters such as the detonation pressure, velocity, energy, and temperature were computed using the EXPLO5 code.  相似文献   

2.
This contribution covers the preparation and characterization of 2,2‐bis(5‐tetrazolyl)propane (5‐DTP) ( 1 ). The bridged bitetrazole is used as a neutral nitrogen‐rich ligand in 3d transition metal(II) based complexes for the first time and can be synthesized via [2+3] cycloaddition from sodium azide and dimethylmalononitrile. The combination with different anions (e.g., perchlorate, nitrate, sulfate, and chloride) yields materials with widely varying physicochemical properties. The obtained coordination compounds were characterized using low‐temperature single‐crystal X‐ray diffraction (except 14 ), IR spectroscopy, elemental analysis, and DTA (except 16 ). The sensitivities toward external stimuli (impact and friction) were determined according to the Bundesamt für Materialforschung und ‐prüfung (BAM) standard methods together with its sensitivities against electrostatic discharge (except 16 ). Complexes 10 and 14 were characterized in laser ignition experiments. For determination of the compounds' deflagration to detonation transition (DDT) capability, hot plate and hot needle tests were performed for the zinc(II) and copper(II) perchlorate complexes.  相似文献   

3.
The synthesis of 3,3′‐bis(dinitromethyl)‐5,5′‐azo‐1H‐1,2,4‐triazole ( 5 ) using the readily available starting material 2‐(5‐amino‐1H‐1,2,4‐triazol‐3‐yl)acetic acid ( 1 ) is described. All compounds were characterized by means of NMR, IR, and Raman spectroscopy. The energetic compound 5 was additionally characterized by single‐crystal X‐ray diffraction and DSC measurements. The sensitivities towards impact, friction and electrical discharge were determined. In addition, detonation parameters (e.g. heat of explosion, detonation velocity) of the target compound were computed using the EXPLO5 code based on the calculated (CBS‐4M) heat of formation and X‐ray density.  相似文献   

4.
4, 4′,5, 5′‐Tetranitro‐2, 2′‐bisimidazole (TNBI) was synthesized by nitration of bisimidazole (BI) and recrystallized from acetone to form a crystalline acetone adduct. Its ammonium salt ( 1 ) was obtained by the reaction with gaseous ammonia. In order to explore new explosives or propellants several energetic nitrogen‐rich 2:1 salts such as the hydroxylammonium ( 3 ), guanidinium ( 4 ), aminoguanidinium ( 5 ), diaminoguanidinium ( 6 ) and triaminoguanidinium 7 4, 4′,5, 5′‐tetranitro‐2, 2′‐bisimidazolate were prepared by facile metathesis reactions. In addition, methylated 1, 1′‐dimethyl‐4, 4′,5, 5′‐tetranitro‐2, 2′‐bisimidazole (Me2TNBI, 8 ) was synthesized by the reaction of 2 and dimethyl sulfate. Metal salts of TNBI can also be easily synthesized by using the corresponding metal bases. This was proven by the synthesis of pyrotechnically relevant dipotassium 4, 4′,5, 5′‐tetranitro‐2, 2′‐bisimidazolate ( 2 ), which is a brilliant burning component e.g. in near‐infrared flares. All compounds were characterized by single crystal X‐ray diffraction, NMR and vibrational spectroscopy, elemental analysis and DSC. The sensitivities were determined by BAM methods (drophammer and friction tester). The heats of formation were calculated using CBS‐4M electronic enthalpies and the atomization method. With these values and mostly the X‐ray densities different detonation parameters were computed by the EXPLO5 computer code. Due to the great thermal stability and calculated energetic properties, especially guanidinium salt 4 could be served as a HNS replacement.  相似文献   

5.
1,1′‐Bis(trimethylsilylamino)ferrocene reacts with trimethyl‐ and triethylgallium to give the μ‐[ferrocene‐1,1′‐diyl‐bis(trimethylsilylamido)]tetraalkyldigallanes. These were converted into the 1,3‐bis(trimethylsilyl)‐2‐alkyl‐2‐pyridine‐1,3,2‐diazagalla‐[3]ferrocenophanes, of which the ethyl derivative was characterized by X‐ray structural analysis. Treatment of gallium trichloride with N,N′‐dilithio‐1,1′‐bis(trimethylsilylamino)ferrocene affords μ‐[ferrocene‐1,1′‐diyl‐bis(trimethylsilylamido)]tetrachlorodigallane along with bis(trimethylsilyl)‐2,2‐dichloro‐1‐aza‐3‐azonia‐2‐gallata‐[3]ferrocenophane as a side product, and both were structurally characterized by X‐ray analysis. The solution‐state structures of the new gallium compounds and aspects of their molecular dynamics in solution were studied by NMR spectroscopy (1H, 13C, 29Si NMR).  相似文献   

6.
A conjugated polymer with a butatriene segment in the main chain, poly(biphenyl‐4,4′‐diyl‐1,4‐bis(4‐dodecyloxyphenyl)buta‐1,2,3‐triene‐1,4‐diyl), was synthesized from 1,4‐bis(4‐bromophenyl)‐1,4‐bis(4‐dodecyloxyphenyl)buta‐1,2,3‐triene by dehalogenative polycondensation using Ni(cod)2. The polymer was well soluble in usual organic solvents such as CHCl3 and THF. Structural analyses and characterizations were carried out by IR, NMR, UV‐Vis, PL, and Raman spectroscopy, as well as electrical conductivity. It is suggested that π‐conjugation is extended to some degree through biphenylylene and butatrienylene linkages.  相似文献   

7.
A large variety of twice‐deprotonated nitrogen‐rich 5,5′‐bistetrazolates, that is, the ammonium ( 1 ), hydrazinium ( 2 ), hydroxylammonium ( 3 ), guanidinium ( 4 ), aminoguanidinium ( 5 ), diaminoguanidinium ( 6 ), triaminoguanidinium ( 7 ), and diaminouronium ( 8 ) salts, have been synthesized. Energetic compounds 1 – 8 were fully characterized by single‐crystal X‐ray diffraction (except 8 ), NMR spectroscopy, IR and Raman spectroscopy, and differential scanning calorimetry (DSC) measurements. With respect to their potential use in propellant applications, the sensitivity towards impact, friction, and electrical discharge were determined. Several propulsion and detonation parameters (e.g., heat of explosion, detonation velocity) were computed by using the EXPLO5 computer code based on calculated (CBS‐4M) heats of formation and X‐ray densities. Additionally, the performance of 1 – 8 in various formulations was investigated by calculating the specific energy and specific impulse of the compounds under isochoric conditions.  相似文献   

8.
1‐Hydroxy‐5‐aminotetrazole ( 1 ), which is a long‐desired starting material for the synthesis of hundreds of new energetic materials, was synthesized for the first time by the reaction of aqueous hydroxylamine with cyanogen azide. The use of this unique precursor was demonstrated by the preparation of several energetic compounds with equal or higher performance than that of commonly used explosives, such as hexogen (RDX). The prepared compounds, including energetic salts of 1‐hydroxy‐5‐aminotetrazole (hydroxylammonium ( 2 , two polymorphs) and ammonium ( 3 )), azo‐coupled derivatives (potassium ( 5 ), hydroxylammonium ( 6 ), ammonium ( 7 ), and hydrazinium 5,5′‐azo‐bis(1‐N‐oxidotetrazolate ( 8 , two polymorphs)), as well as neutral compounds 5,5′‐azo‐bis(1‐oxidotetrazole) ( 4 ) and 5,5′‐bis(1‐oxidotetrazole)hydrazine ( 9 ), were intensively characterized by low‐temperature X‐ray diffraction, IR, Raman, and multinuclear NMR spectroscopy, elemental analysis, and DSC. The calculated energetic performance, by using the EXPLO5 code, based on the calculated (CBS‐4M) heats of formation and X‐ray densities confirm the high energetic performance of tetrazole‐N‐oxides as energetic materials. Last but not least, their sensitivity towards impact, friction, and electrostatic discharge were explored. 5,5′‐Azo‐bis(1‐N‐oxidotetrazole) deflagrates close to the DDT (deflagration‐to‐detonation transition) faster than all compounds that have been investigated in our research group to date.  相似文献   

9.
Two highly energetic nitric acid esters were synthesized from the dimer of dihydroxyacetone. 1,3‐Dinitratoacetone ( 1 ) and its dimer 2,5‐bis(nitratomethyl‐2,5‐nitrato)‐1,4‐dioxane ( 2 ) were characterized by single‐crystal X‐ray diffraction, vibrational spectroscopy (IR and Raman), multinuclear NMR spectroscopy, and elemental analysis. The thermal behavior was investigated with DTA measurements. Although showing the same atomic stoichiometry, dimer 2 shows significantly higher sensitivities measured by BAM methods (drophammer and friction tester). Due to the high oxygen content of 62.2 %, 1 and 2 were evaluated as potential high energy dense oxidizers.  相似文献   

10.
This study features the preparation of three new energetic C‐azido‐1, 2, 4‐triazoles, with the anion of one being a new binary C–N compound. 5‐Azido‐1H‐1, 2, 4‐triazole‐3‐carbonitrile ( 1 ) was prepared from 5‐amino‐1H‐1, 2, 4‐triazole‐3‐carbonitrile and further derivatized to 5‐azido‐1H‐1, 2, 4‐triazole‐3‐carbohydroximoyl chloride ( 5 ) with 3‐azido‐1H‐1, 2, 4‐triazole‐5‐carboxamidoxime ( 3 ) as an intermediate. The ability of 1 and 3 for salt formation was shown with the respective silver salts 2 and 4 . All compounds were well characterized by various means, including IR and multinuclear NMR spectroscopy, mass spectrometry, and DSC. The molecular structures of 1 , 3 , and 5 in the solid state were determined by single‐crystal X‐ray diffraction. The sensitivities towards various outer stimuli (impact, friction, electrostatic discharge) were determined according to BAM standards. The silver salts were additionally tested for their potential as primary explosives.  相似文献   

11.
Various energetic polynitro esters, carbamates, and nitrocarbamates that were derived from the amino acid glycine were fully characterized by single‐crystal X‐ray diffraction, vibrational spectroscopy (IR and Raman), multinuclear NMR spectroscopy, elemental analysis, and differential scanning calorimetry (DSC). Owing to their positive oxygen balance, the suitability of these compounds as potential oxidizers in energetic formulations was investigated and discussed. In addition, the heats of formation of the products were calculated by using the Gaussian 09 program package at the CBS‐4M level of theory. From these values and the calculated densities (from the X‐ray data), several detonation parameters, such as detonation pressure, velocity, energy, and temperature, were computed by using the EXPLO5 code. Furthermore, their sensitivities towards impact, friction, and electrostatic discharge were tested by using a drop hammer, a friction tester (both BAM certified), and a small‐scale electrical‐discharge device, respectively.  相似文献   

12.
3,5‐Diamino‐1,2,4‐triazole ( 1 , guanozol) was protonated with diluted hydrochloric acid, nitric acid, as well as perchloric acid forming 3,5‐diamino‐1,2,4‐triazolium chloride hemihydrate ( 2 ), 3,5‐diamino‐1,2,4‐triazolium nitrate ( 3 ) and 3,5‐diamino‐1,2,4‐triazolium perchlorate ( 4 ), respectively. In a second step 4 reacted with potassium dinitramide forming 3,5‐diamino‐1,2,4‐triazolium dinitramide ( 5 ) and low soluble potassium perchlorate. Compounds 2 – 5 were characterized by low temperature single X‐ray diffraction, IR and Raman as well as multinuclear NMR spectroscopy, mass spectrometry and differential scanning calorimetry. The heats of formation of 1 – 5 were calculated by the CBS‐4M method to be 81.1 ( 1 ), 124.7 ( 2 ), –76.1 ( 3 ), –25.2 ( 4 ) and 138.7 ( 5 ) kJ·mol–1. With these values as well as the X‐ray densities several detonation parameters were calculated using both computer codes EXPLO5.03 and EXPLO5.04. In addition, the sensitivities of 1 – 5 were determined by the BAM drophammer and friction tester as well as a small scale electrical discharge device.  相似文献   

13.
In this contribution, the synthesis and full structural and spectroscopic characterization of five bis‐1,2,4‐triazoles in combination with different energetic moieties like amino, nitro, nitrimino, azido, and dinitromethylene groups is presented. The main goal is a comparative study on the influence of those energetic moieties on the structural and energetic properties. A complete characterization including IR, Raman, and multinuclear NMR spectroscopy of all compounds is presented. Additionally, X‐ray crystallographic measurements were performed and deliver insight into structural characteristics as well as inter‐ and intramolecular interactions. The standard enthalpies of formation were calculated for all compounds at the CBS‐4M level of theory, the detonation parameters were calculated by using the EXPLO5.05 program. Additionally, the impact as well as the friction sensitivities and the sensitivity against electrostatic discharge were determined. The potential application of the synthesized compounds as energetic material will be studied and evaluated by using the experimentally obtained values for the thermal decomposition, the sensitivity data, and the calculated performance characteristics.  相似文献   

14.
The synthesis of 5,5′‐diamino‐3,3′‐azo‐1H‐1,2,4‐triazole ( 3 ) by reaction of 5‐acetylamino‐3‐amino‐1H‐1,2,4‐triazole ( 2 ) with potassium permanganate is described. The application of the very straightforward and efficient acetyl protection of 3,5‐diamino‐1H‐1,2,4‐triazole allows selective reactions of the remaining free amino group to form the azo‐functionality. Compound 3 is used as starting material for the synthesis of 5,5′‐dinitrimino‐3,3′‐azo‐1H‐1,2,4‐triazole ( 4 ), which subsequently reacted with organic bases (ammonia, hydrazine, guanidine, aminoguanidine, triaminoguanidine) to form the corresponding nitrogen‐rich triazolate salts ( 5 – 9 ). All substances were fully characterized by IR and Raman as well as multinuclear NMR spectroscopy, mass spectrometry, and differential scanning calorimetry. Selected compounds were additionally characterized by low temperature single‐crystal X‐ray diffraction measurements. The heats of formation of 4 – 9 were calculated by the CBS‐4M method to be 647.7 ( 4 ), 401.2 ( 5 ), 700.4 ( 6 ), 398.4 ( 7 ), 676.5 ( 8 ), and 1089.2 ( 9 ) kJ · mol–1. With these values as well as the experimentally determined densities several detonation parameters were calculated using both computer codes EXPLO5.03 and EXPLO5.04. In addition, the sensitivities of 5 – 9 were determined by the BAM drophammer and friction tester as well as a small scale electrical discharge device.  相似文献   

15.
The novel mesoporous silica‐supported bis(diazo‐azomethine) compounds have been synthesized and characterized successively. In the first step, 1,3‐phenylenedimethanamine and 4,4′‐diaminodiphenylmethane were diazotized, and the obtained bis(diazonium) cations were coupled with 2,4‐dihydroxybenzaldehyde. The synthesized bis(diazo‐carbonyl) compounds, 5,5′‐((1,3‐phenylenebis(methylene))bis(diazene‐2,1‐diyl))bis(2,4‐dihydroxybenzaldehyde) (A1) and 5,5′‐((methylenebis(4,1‐phenylene))bis(diazene‐2,1‐diyl))bis(2,4‐dihydroxybenzaldehyde) (A2) were chemically supported on amino‐modified silica‐gel (as L1 and L2). Elemental analysis, liquid chromatography‐mass spectroscopy, liquid‐phase NMR (1H and 13C) and solid‐phase NMR (CP‐MAS 29Si and 13C), FT‐IR, TG/DTA, scanning electron microscopy and energy‐dispersive X‐ray spectroscopy techniques were used for characterizations of all the synthesized compounds. The syringe and batch techniques were applied for the solid‐phase extraction properties of Pb(II), Cu(II), Cd(II) and Cr(III) ions using an inductively coupled plasma‐atomic emission spectroscopy instrument. The recoveries of Pb(II), Cu(II), Cd(II) and Cr(III) ions have been achieved to 95–99% with the (RSDs) of ± 2–3% in optimum conditions.  相似文献   

16.
2-Methyl-5-nitraminotetrazole (1) was formed by nitration of 2-methyl-5-aminotetrazole. 2-Methyl-5-aminotetrazole was obtained by an improved synthesis starting from sodium 5-aminotetrazolate, which is methylated with dimethyl sulfate in dimethyl formamide giving 2-methyl-5-aminotetrazole in 29% yield. Nitrogen-rich salts such as guanidinium (2), 1-aminoguanidinium (3), 1,3-diamino-guanidinium (4), 1,3,5-triamino-guanidinium (5), azidoformamidinium (6), hydrazinium (7), diaminouronium 2-methyl-5-nitraminotetrazolate (8), as well as an urea adduct (9), were prepared by facile deprotonation or metathesis reactions. Diaminourea was synthesized by hydrazinolysis of dimethyl carbonate with hydrazine hydrate. All compounds were fully characterized by vibrational spectroscopy (IR and Raman), multinuclear NMR spectroscopy, elemental analysis, and differential scanning calorimetry (DSC) measurements. The crystal structures of 2-6, 8, and 9 could be determined using single crystal X-ray diffraction. The heats of formation of 2-9 were calculated using the atomization method based on CBS-4M enthalpies. With these values and the experimental (X-ray) densities several detonation parameters such as the detonation pressure, velocity, energy, and temperature were computed using the EXPLO5 code. In addition, the sensitivities toward impact, friction, and electrical discharge were tested using the BAM drop hammer, BAM friction tester, as well as a small scale electrical discharge device.  相似文献   

17.
New energetic bis(2, 2‐dinitroethyl‐N‐nitro)ethylenediamine‐based salts exhibiting moderate physical properties, good detonation properties, and relatively low impact sensitivities were synthesized in high yield by direct reactions of bis(2, 2‐dinitroethyl‐N‐nitro)ethylenediamine with organic bases. The resulting salts were fully characterized by multinuclear NMR spectroscopy (1H and 13C), vibrational spectroscopy (IR), differential scanning calorimetry (DSC), and elemental analysis. Solid‐state 15N NMR spectroscopy was used as an effective technique to further determine the structure of some products. Thermal decomposition kinetics and several thermodynamic parameters of some salts were obtained under non‐isothermal conditions by DSC. The densities of the energetic salts paired with organic cations were in the range 1.60–1.89 g · cm–3 as measured with 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 be 23.6–44.8 GPa and 7790–9583 m · s–1, respectively, which make them potentially useful as energetic materials.  相似文献   

18.
2,6‐Bis(picrylamino)pyridine ( 1 ; pre‐PYX) and 2,6‐bis(picrylamino)‐3,5‐dinitropyridine ( 2 ; PYX) were synthesized using an improved literature method. Compounds 1 and 2 were reinvestigated in detail and the X‐ray structures ( 1 : ρ=1.698 g cm?3 at 173 K; 2 : ρ=1.757 g cm?3 at 298 K) are given. The reactions of 2 with different bases, such as alkali metal hydroxides (sodium, potassium, rubidium, cesium), and N‐bases (ammonia, hydrazine, hydroxylamine, guanidinium carbonate, aminoguanidine bicarbonate) are reported, as well as metathesis reactions producing energetic salts. Several energetic compounds were synthesized and characterized for the first time using vibrational (IR, Raman) and multinuclear NMR spectroscopy, mass spectrometry, elemental analysis, and DSC. The crystal structures of four energetic salts were determined using low temperature single‐crystal X‐ray diffraction. Heats of formation for the metal‐free species were calculated using the Gaussian 09 software. Detonation parameters were estimated using the EXPLO5 program. The sensitivities towards impact, friction, and electrostatic discharge were also determined.  相似文献   

19.
Magnesium azotetrazole‐1,1′‐dioxide ( 1 ) was first prepared and intensively characterized by single‐crystal X‐ray diffraction, IR spectroscopy, mass spectrometry, elemental analysis, and DSC measurements. The heat of formation was calculated using the atomization energy method based on quantum chemistry and the heat of detonation was also predicted. The NBO analysis was performed for inspecting charge distributions. The sensitivities towards impact and friction were tested using the BAM standard. The high detonation performance (5289 kJ · kg–1), good thermal stabilities (245.5 °C) and excellent insensitivity (39.2 J and >360 N) as well as clean decomposition products supports it of great interest as a promising candidate of green insensitive energetic materials.  相似文献   

20.
《Electroanalysis》2006,18(4):417-422
In dimethylformamide containing tetramethylammonium tetrafluoroborate, cyclic voltammograms for reduction of 4,4′‐(2,2,2‐trichloroethane‐1,1‐diyl)bis(chlorobenzene) (DDT) at a glassy carbon cathode exhibit five waves, whereas three waves are observed for the reduction of 4,4′‐(2,2‐dichloroethane‐1,1‐diyl)bis(chlorobenzene) (DDD). Bulk electrolyses of DDT and DDD afford 4,4′‐(ethene‐1,1‐diyl)bis(chlorobenzene) (DDNU) as principal product (67–94%), together with 4,4′‐(2‐chloroethene‐1,1‐diyl)bis(chlorobenzene) (DDMU), 1‐chloro‐4‐styrylbenzene, and traces of both 1,1‐diphenylethane and 4,4′‐(ethane‐1,1‐diyl)bis(chlorobenzene) (DDO). For electrolyses of DDT and DDD, the coulometric n values are essentially 4 and 2, respectively. When DDT is reduced in the presence of a large excess of D2O, the resulting DDNU and DDMU are almost fully deuterated, indicating that reductive cleavage of the carbon–chlorine bonds of DDT is a two‐electron process that involves carbanion intermediates. A mechanistic scheme is proposed to account for the formation of the various products.  相似文献   

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