Heterocyclic-based nitrodicyanomethanide and dinitrocyanomethanide salts: a family of new energetic ionic liquids

Twelve novel energetic salts 1a-f and 2a-f with nitrodicyanomethanide and dinitrocyanomethanide anions paired with 1,5-diamino-4-methyltetrazolium, 1,4-dimethyl-5-aminotetrazolium 1,4,5-trimethyltetrazolium, 1-methyl-4-amino-1,2,4-triazolium, 1,4-dimethyltriazolium, and 1,3-dimethylimidazolium have been prepared through metathesis reactions of equivalent silver(I) salts with corresponding iodide salts in acetonitrile. Key physical properties, such as melting point, thermal stability and density, were measured. The relationship between their structures and these properties was determined. The structures of 1,5-diamino-4-methyltetrazolium-based salts 1a and 2a were further confirmed by single-crystal X-ray analysis. The densities and standard enthalpies of formation for these energetic salts were calculated. All of the salts possess higher enthalpies of formation than the nitrate analogues.     

1-磺酰基-3,5-二氨基-1H-吡唑-4-腈的合成及其生物活性

除草剂;1-磺酰基-3;5-二氨基-1H-吡唑-4-腈的合成及其生物活性     

Derivatives of 2,4-diamino-6-methylpteridine

Eighteen derivatives of 2,4-diamino-6-methylpteridine related to methotrexate and aminopterin have been prepared from 6-(bromomethyl)-2,4-pteridinediamine by nucleophilic displacement reactions. None of these compounds showed any antileukemic acitivity.     

Derivatives of 1,5-diborocane

Russian Chemical Bulletin -     

3-Azido-N-nitro-1H-1,2,4-triazol-5-amine-based energetic salts

Twelve energetic nitrogen‐rich salts based on 3‐azido‐N‐nitro‐1H‐1,2,4‐triazol‐5‐amine were prepared and fully characterized by ¹H, ¹³C NMR, and IR spectroscopy, differential scanning calorimetry (DSC), and elemental analysis. The crystal structures of the neutral compound 3‐azido‐N‐nitro‐1H‐1,2,4‐triazole‐5‐amine ( 1 ) and its triaminoguanidinium salt ( 13 ) were determined by single‐crystal X‐ray diffraction. The density of 1 and its twelve salts ranged from 1.57 to 1.79 g cm^?3, and the heat of formation was calculated with the Gaussian 03 suite of programs. Compounds 1 – 13 exhibit promising detonation performances (pressure: 25.3–39.3 GPa; velocity: 8159–9409 ms^?1; EXPLO 5.05). Impact sensitivities were also determined by hammer tests and resulted ranging from 2.5 J (very sensitive) to >40 J (insensitive).     

Structure and energetic properties of 1,5-dinitrobiuret

The two-dimensional potential energy scan shows that the pseudo-trans conformer of 1,5-dinitrobiuret (DNB) is the most stable form of isolated molecule, while the pseudo-cis conformer is about 7.5 kJ/mol higher in energy. Thus, the structure of gaseous DNB is different from that in crystal state, where the molecules have pseudo-cis conformation. The value of enthalpy of formation of gaseous DNB (?257 ± 5 kJ/mol) is calculated from isodesmic reactions using G4 energies. Combining this value with empirically estimated enthalpy of sublimation, the enthalpy of formation of crystal DNB is predicted to be ?415 ± 15 kJ/mol. The bond dissociation enthalpies are calculated for all bonds. The energy of the weakest N–NO₂ bonds is equal to 190–200 kJ/mol. Similar calculations were carried out for biuret. The gaseous biuret exists predominantly in the pseudo-trans form. The calculated enthalpy of formation of gaseous biuret agrees well with the experimental one. The correlation of calculated bond energies with corresponding bond distances and electron density is discussed for biuret and DNB.     

Novel (1H-tetrazol-5-yl-NNO-azoxy)furazans and their energetic salts: synthesis,characterization and energetic properties

Six novel energetic furazans containing tetrazol-5-yl-NNO-azoxy moiety were synthesized using (cyano-NNO-azoxy)-furazans as starting compounds. The obtained compounds exhibit high enthalpies of formation (531–792 kcal kg^–1), acceptable densities (1.70–1.76 g cm^–3), good thermal stability (T_onset = 146–199 °C), and, as a result, excellent detonation performance (detonation velocities of 8.61–8.95 km s?1 and detonation pressures of 31.6–36.0 GPa).     

Synthesis and promising properties of a new family of high-density energetic salts of 5-nitro-3-trinitromethyl-1H-1,2,4-triazole and 5,5'-bis(trinitromethyl)-3,3'-azo-1H-1,2,4-triazole

Salts of trinitromethyl-substituted triazoles, 5-nitro-3-trinitromethyl-1H-1,2,4-triazole and 5,5'-bis(trinitromethyl)-3,3'-azo-1H-1,2,4-triazole (5), form a new class of highly dense energetic materials. Single-crystal X-ray structuring supports the formation of the cocrystal of 5 with 3,5-diamino-1,2,4-triazole, which was found to be remarkably less impact-sensitive than the azo precursor. The compounds were fully characterized using IR and multinuclear NMR spectroscopy, elemental analysis, and differential scanning calorimetry. Based on heats of formation calculated with Gaussian 03 and combined with experimentally determined densities, detonation properties of the energetic materials obtained with the EXPLO5 program identify them as potentially explosive compounds. They exhibit high density, moderate to good thermal stability, acceptable oxygen balance, reasonable heat of formation, and excellent detonation properties, which in some cases are superior to those of 1,3,5,-trinitrotriazacyclohexane (RDX).     

Synthesis of Novel Derivatives of 1,5-Benzothiazepines (Part 1)

Synthesis of 2,4-disubstituted 1,5-benzothiazepines 3a-3i is reported by the condensation of 2-aminothiophenol 1 with 1,3-diones in pyridine. The structures of the compounds have been established by elemental, IR, 1 H NMR, 13 C NMR, and mass spectral analyses.     

Functionalization graphene oxide with energetic groups as a new family of metal-free and energetic burning rate catalysts and desensitizers for ammonium perchlorate

Journal of Thermal Analysis and Calorimetry - A new family of metal-free and energetic graphene oxide (GO)-based burning rate catalysts (FGO 1–6) with excellent catalytic and desensitization...     

含能材料2,6-二胺-3,5-二硝基吡嗪-1-氧化物的B3LYP 研究

在B3LYP/6-31G^**水平下,研究了LLM-105的稳定几何构型,并进行了集居数分析,自然键轨道(NBO)分析,成键轨道分析,以及振动光谱分析。根据计算可知,LLM-105分子中所有原子均处于同一平面,分子是由一个除了H以久所有原子均参与的大的Ⅱ共轭体系构成;分子内存在着较强的氢键,使分子的稳定性增强;以C-NO2的C-N键键强度最小,可能是分解引发键,在爆炸时最先断裂。     

Competition between π–π stacking and hydrogen bonding in (1:2) picrates of 1,5-diamino-3-oxapentane, 1,8-diamino-3,6-dioxaoctane and 1,5-diamino-3-azapentane—solid state studies

Crystallographic studies of (2:1) salts of picric acid with 1,5-diamino-3-oxapentane (1OPICR), 1,8-diamino-3,6-dioxaoctane (2OPICR) and 1,5-diamino-3-azapentane (1NPICR) showed significant conformational change of the picrate ion due to numerous electrostatic, H-bonding and π–π stacking interactions present in the crystal lattice. In particular, intermolecular N–HO H-bonds were found to cause significant twisting of the o-NO₂ groups from the plane of the benzene ring, whereas overlapping of the picrate ions due to electrostatic interactions and π–π stacking caused flattening of the molecule. Analysis of the geometry of 74 picrate ions found in the Cambridge Crystallographic Database, in their various crystallochemical environments, showed that competition between essentially weak but numerous intermolecular interactions of different types led to systematic changes in geometric parameters within the picrate ion. In particular, relations found between the C1–C2–N–O (C1–C6–N–O) torsion angle and the endocyclic C1–C2–C3 (C1–C6–C5) valence angle can be explained on the basis of competition between resonance effects of the o-NO₂ group and π–π stacking.     

Interaction of 2,4,6-heptanetrione with 1,5-diamino-3-azapentane and similar polyamines. The crystal and molecular structure of a new heterocyclic compound

The pathway of the reaction between 2,4,6-heptanetrione and 1,5-diamine-3-aza-pentane was studied and some products identified by ir, uv, mass spectra and x-ray diffractometry. This reaction is not a simple condensation with the formation of a Schiff base but a more complicated process. The structure of the final compound was determined by x-ray crystallography and refined to R = 0.047. Crystals are triclinic, space group Pl, with a = 11.795(5), b = 9.779(5), c = 7.801(5) Å, α = 101.74(3), β = 90.93(3), γ = 110.65(3), Dx = 1.27 g. cm^?3 for Z = 2. The structure is essentially formed by three heterorings two of which have a common edge. Only the 4-pyridone ring is planar. As expected 1,5-diamino-3-thiapentane reacts with the same triketone, in 1:1 or 1:2 molar ratios, to give the acyclic or macrocyclic Schiff bases.     

由1,5-二羟基多羟基烃合成哌啶衍生物

以1,5-二羟基多羟基烃为原料,通过磺酰化转化为活泼的1,5-二磺酸酯,再与不同类型的伯胺化合物反应生成多羟基哌啶衍生物。 探讨了反应温度、反应时间和伯胺类型等条件对成环反应的影响,当反应温度为90~100 ℃、反应时间为18 h时,成环反应的收率达到了74%~94%。     

1,5-苯并二氮杂的合成及其生物活性研究

采用两种方法: 以三氧化铝为载体邻苯二胺与查尔酮为原料的无溶剂合成法和以PPA(多聚磷酸)为催化剂邻苯二胺与苯乙酮的一锅合成法, 合成了1,5-苯并二氮杂, 产物收率为53.7%～74.5%. 通过¹H NMR, ¹³C NMR, MS, IR, 元素分析等手段对所合成的化合物进行了结构确定, 并测试了它们对菌和乙酰胆碱酶的抑制活性.     

Simple, nitrogen-rich, energetic salts of 5-nitrotetrazole

A new family (ammonium, 1, hydrazinium, 2, guanidinium, 3, aminoguanidinium, 4, diamino-guanidinium, 5, and triaminoguanidinium, 6) of simple, nitrogen-rich energetic salts based on 5-nitro-2 H-tetrazole (HNT) were synthesized. In addition, the hemihydrate of 1 (1a) and the hydrate of 6 (6a) were also isolated. In all cases, stable salts were obtained and fully characterized by vibrational (IR, Raman) spectroscopy, multinuclear ((1)H, (13)C and (14)N) NMR spectroscopy, mass spectrometry, elemental analysis, and X-ray structure determination. Compounds 1and 2 crystallize in the monoclinic space group P2 1/c, 1a and 3 crystallize in C/2 c, 4 in P2 1/n, 5 in P2 1, 6 in orthorhombic P2 12 12 1, and 6a in triclinic P1. Initial safety testing (impact, friction, and electrostatic sensitivity) and thermal stability measurements (DSC) were also carried out. The NT salts all exhibit good thermal stabilities (decomposition above 150 degrees C). The constant volume energies of combustion (Delta c U(exp)) of 1-6 were experimentally determined by oxygen bomb calorimetry to be -1860(30) cal/g ( 1), -1770(30) cal/g ( 1a), -2110(150) cal/g (2), -2250(40) cal/g ( 3), -2470(30) cal/g (4), -2630(40) cal/g (5), -2690(50) cal/g (6), and -2520(50) cal/g (6a). Because of the significant experimental uncertainties obtained in these measurements, their validity was checked by way of quantum chemical calculation (MP2) of electronic energies and an approximation of lattice enthalpy. The predicted constant volume energies of combustion (Delta c U(pred)) calculated by this method were -2095.9 cal/g (1), -1975.7 cal/g ( 1a), -2362.4 cal/g (2), -2526.6 cal/g (3), -2654.6 cal/g (4), -2778.6 cal/g ( 5), -2924.0 cal/g (6), and -2741.4 cal/g ( 6a). From the experimentally determined density, chemical composition, and energies of formation (back calculated from the heats of combustion) the detonation pressures and velocities of 1 (7950 m/s, 23.9 GPa), 1a (7740 m/s, 22.5 GPa), 2(8750 m/s, 30.1 GPa), 3 (7500 m/s, 20.1 GPa) 4(8190 m/s, 24.7 GPa), 5(8230 m/s, 24.4 GPa), 6 (8480 m/s, 26.0 GPa) and 6a (7680 m/s, 20.7 GPa) were predicted using the EXPLO5 code.     

N-Amination of 3-amino-1,2,4-triazole with hydroxylamine-O-sulfonic acid: Synthesis of 1,5-diamino-1,2,4-triazole

N-Amination of the 3(5)-amino-1,2,4-triazolide anion with hydroxylamine-O-sulfonic acid is studied. This method provided an access to the previously unknown 1,5-diamino-1,2,4-triazole.