A promising strategy was utilized to boost the detonation performance of energetic salts. The desired 4,4′,5,5′-tetraamino-4
H
,4′
H
-3,3′-bi(1,2,4-triazole)-1,1′-diium 1′-hydroxy-1
H
,1′
H
...-5,5′-bitetrazol-1-olate TABT
2+
(HBTO
−
)
2
was synthesized by controlling the ratio between the cation and anion (1 : 2) during the synthesis of 4,4′,5,5′-tetraamino-4
H
,4′
H
-3,3′-bi(1,2,4-triazole)-1,1′-diium 1
H
,1′
H
-5,5′-bitetrazole-1,1′-bis(olate) (TABT
2+
BTO
2−
). The bivalent cation-bivalent anion salt changed into bivalent cation-univalent anion salt easily as confirmed by single-crystal X-ray diffraction, NMR spectroscopy, IR spectroscopy, DSC, and elemental analysis. Compared with TABT
2+
BTO
2−
, the density, heat of formation, detonation velocity and detonation pressure of TABT
2+
(HBTO
−
)
2
increased by 0.165 g cm
−3
(10.0%), 1.81 kJ g
−1
(111.0%), 549 m s
−1
(6.8%) and 11.5 GPa (52.0%), respectively. Meanwhile, the enhanced properties of HBTO
−
salt do not come at the expense of molecular stability, just from changing one insensitive explosive to another more energetic insensitive explosive (IS > 40 J, FS > 360 N,
T
dec.,onset
= 271.8 °C). This work provides a promising route to enhance the properties of energetic salts.
A promising strategy was utilized to boost the detonation performance of insensitive energetic salts.
Sensors 4 and Sensor L-5 were successfully applied in enantioselective discrimination.
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•Three novel sensors L-4, D-4 and L-5 were synthesized and characterized.•The chiral sensors ...were applied in enantioselective discrimination.•The relationship between the discrimination and the structures.
New chiral fluorescent sensors derived from tetraphenylethylene and proline hydrazide were synthesized and applied in the chiral recognition of various chiral compounds, including unprotected amino acids, acidic compounds, chiral amines and even neutral alcohols. These results demonstrated that the excellent enantioselective response ability to various chiral substrates could be attributed to the –NH moieties of pyrrolidine ring and thiourea unit which acted as hydrogen-bonding donors. This result is of potential significance in enantiomeric discrimination and high-throughput analysis of the enantiomeric purity of chiral guests.
A series of cyclo-N5−-based lead-containing energetic coordination polymers Pb(OH)4(N5)4 (1), Pb3(N5)3(H2O)9(NO3)4(N5)8(H2O)5 (2), Pb(OH)4(N5)3(NO3)(H2O)3 (3), and Pb(OH)4(N5)3(ClO4)(H2O) (4) were ...synthesized by self-assembly and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, infrared and Raman spectroscopy, high resolution mass spectrometry, elemental analysis, scanning electron microscopy, and differential scanning calorimetry. In addition, their thermal decomposition kinetics have been studied theoretically and experimentally. The results revealed that the synthesized CPs possess regular structures, very high densities (2.852–4.537 g cm−3), good oxygen balances (CO2) (−2.72–+2.61%), good thermal stabilities (80–110 °C), and acceptable sensitivities (9.5–20 J; 120–240 N). This work will provide new inspiration for the development of cyclo-N5−-based coordination polymers and energetic materials.
A series of
-N
-based lead-containing energetic coordination polymers Pb(OH)
(N
)
(1), Pb
(N
)
(H
O)
(NO
)
(N
)
(H
O)
(2), Pb(OH)
(N
)
(NO
)(H
O)
(3), and Pb(OH)
(N
)
(ClO
)(H
O) (4) were synthesized ...by self-assembly and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, infrared and Raman spectroscopy, high resolution mass spectrometry, elemental analysis, scanning electron microscopy, and differential scanning calorimetry. In addition, their thermal decomposition kinetics have been studied theoretically and experimentally. The results revealed that the synthesized CPs possess regular structures, very high densities (2.852-4.537 g cm
), good oxygen balances (CO
) (-2.72-+2.61%), good thermal stabilities (80-110 °C), and acceptable sensitivities (9.5-20 J; 120-240 N). This work will provide new inspiration for the development of
-N
-based coordination polymers and energetic materials.
A safer, convenient, and scalable synthesis for 3,4-bis(4-nitro-1,2,5-oxadiazol-3-yl)-1,2,5-oxadiazole-2-oxide (BNFF or DNTF) is described. The obtained products were fully characterized and further ...confirmed by single-crystal X-ray diffraction. The reaction process of tandem nitration–cyclization was optimized, and the thermal stability of the optimal reaction system was studied. 3-Amino-4-(carboxymethyl)furazan is oxidized and then treated with dilute mixed acid (HNO3 and H2SO4) to obtain BNFF in a yield of 52% and a purity of 99% after liquid chromatography analysis. Compared with some previously reported multistep methods that relied on high-concentration hydrogen peroxide solutions and suffered from dangerous exothermic profiles, this new method used to synthesize BNFF promises to be safer and more efficient.
An N -trinitromethyl strategy was employed for the synthesis of polynitro-pyrazole based high-energy-density compounds with great potential as energetic materials. The new compounds were ...characterized by 1 H and 13 C NMR, IR spectroscopy, elemental analysis, differential scanning calorimetry, and single-crystal X-ray diffraction. Compound 10 exhibits high energetic properties, has a positive oxygen balance (OB) of +2.1%, and an excellent specific impulse (272.4 s), making it a potential high-energy dense oxidizer to replace AP in solid rocket propellants. The nitration of 7 with HNO 3 /H 2 SO 4 yielded the green primary explosive 12, which showed higher density, higher performance, better oxygen balance and lower sensitivities to those of currently used diazodinitrophenol. Compound 13 is a nitrogen and oxygen rich secondary explosive with a high OB (+5.0%), comparable energy ( D = 9030 m s −1 ; P = 35.6 GPa; η = 1.03) to HMX, and much lower mechanical sensitivity (IS = 12 J, FS = 240 N).
The research of all-nitrogen compounds has always been a hot topic in nitrogen chemistry and high-energy-density material communities. This research mainly focuses on acyclic and monocyclic ...all-nitrogen derivatives, while the bicyclic systems of all-nitrogen materials have been rarely investigated. In this study, four bicyclic all-nitrogen derivatives, viz bridged N10 and N12 , and caged N10 and N12 , are presented. Caged- N10 and caged- N12 exhibit much higher density ( d : 1.84 and 1.89 g cm −3 ) and higher heats of formation ( H f : 15.19 and 16.41 kJ g −1 ) than bridged- N10 and bridged- N12 ( d : 1.71 and 1.72 g cm −3 ; H f : 7.64 and 10.24 kJ g −1 ), respectively. All these materials exhibit remarkable detonation performance ( D : 9.87–12.29 km s −1 ; P : 39.41–72.26 GPa) and excellent specific impulses ( I sp : 325.00–434.60 s), which is superior to the state-of-art CL-20 ( D : 9.40 km s −1 ; P : 44.60 GPa; I sp : 272.61 s), endowing these materials with great potential as promising explosives and propellants. In addition, molecular electrostatic potentials, frontier molecular orbitals, and noncovalent interactions were studied to investigate their structure–property relationship.
Among energetic materials, there is a significant challenge facing researchers: to seek an optimal balance between detonation performance and molecular stability. By introducing an ...azo1,2,4‐oxadiazole backbone and low‐sensitivity C‐NO2 moieties, a promising energetic molecule, 1,2‐bis(3‐nitro‐1,2,4‐oxadiazol‐5‐yl)diazene (4) was prepared through three‐step reaction and well‐characterized by IR and multinuclear NMR spectroscopy, DSC measurement, elemental analysis, and single‐crystal X‐ray diffraction. It shows high thermal stability (Td=260 °C), good mechanical sensitivity (IS: 21 J, FS: 220 N), and superior detonation performance (D: 9336 m s−1, P: 37.7 GPa). The combination of advanced performance and desirable safety as well as the simple reaction process make it highly competitive in the field of energetic materials.
The pentazolate anion, or
cyclo
-N
5
−
, which is a five-membered ring composed solely of nitrogen atoms, has a unique structure among polynitrogen compounds.
Cyclo
-N
5
−
is receiving ...ever-increasing levels of attention because of its potential ability to store large amounts of energy compared to the azide ion, its environmentally friendly decomposition products, and its carbon- and hydrogen-free composition, which are promising characteristics for advancing the field of high-energy-density materials (HEDMs), that include explosives, oxidisers, and propellants in closed environments. In this review, we provide a detailed introduction to
cyclo
-N
5
−
and cover the following topics: (1) substituted pentazoles as precursors of
cyclo
-N
5
−
, with a focus on the syntheses and stabilities of substituted pentazole derivatives; (2) routes to
cyclo
-N
5
−
through cleavage of C-N bonds in substituted pentazoles, during which competitive reactions between pentazole decomposition and C-N bond cleavage need to be considered to ensure a successful outcome; (3) complexes of
cyclo
-N
5
−
, summarising recent progress toward producing
cyclo
-N
5
−
-based complexes through the assembly of isolated
cyclo
-N
5
−
with both metallic and nonmetallic components; and (4) interactions between
cyclo
-N
5
−
and metal cations and non-metal species, as well as factors that influence the stability of these complexes; in particular, the thermal stabilities of prepared
cyclo
-N
5
−
salts are discussed. This review summarises recent studies and is intended to improve the understanding of polynitrogen chemistry while supporting further research into its potential application as an efficient, safe, and environmentally friendly HEDM.
This review summarizes recent developments and advances in pentazole chemistry, including substituted-pentazole precursors, strategies for the preparation of pentazolate anion, derivatives of pentazolate anion and their bonding properties.
Abstract
Among energetic materials, there is a significant challenge facing researchers: to seek an optimal balance between detonation performance and molecular stability. By introducing an ...azo1,2,4‐oxadiazole backbone and low‐sensitivity C‐NO
2
moieties, a promising energetic molecule, 1,2‐bis(3‐nitro‐1,2,4‐oxadiazol‐5‐yl)diazene (4) was prepared through three‐step reaction and well‐characterized by IR and multinuclear NMR spectroscopy, DSC measurement, elemental analysis, and single‐crystal X‐ray diffraction. It shows high thermal stability (T
d
=260 °C), good mechanical sensitivity (IS: 21 J, FS: 220 N), and superior detonation performance (D: 9336 m s
−1
, P: 37.7 GPa). The combination of advanced performance and desirable safety as well as the simple reaction process make it highly competitive in the field of energetic materials.
