An Unusual Layered Crystal Packing Gives Rise to a Superior Thermal Stability of Energetic Salt of 3,6-Bishydrazino-1,2,4,5-tetrazine

Article abstract of DOI:10.1002/zaac.201800086

Five energetic salts of 3,6-bishydrazino-1,2,4,5-tetrazine (BHT), namely (BHT)₂(NTO)₃ (3), (BHT)(BTT)·2H₂O (4), (BHT)(DNP)₂ (5), (BHT)(NATr)₂ (6), and (BHT)(FOX-7)₂ (7), were synthesized and fully characterized by elemental analysis, FT-IR, and mass spectra. The crystal structures of salts 3 and 4 were obtained and determined. Sensitivities towards outside stimuli and thermal behaviors of all the compounds were investigated, besides, thermodynamics of both 3 and 4 were calculated as well. The compounds 3–7 exhibit splendid thermal stabilities and satisfactory sensitivities simultaneously. Notably, unlike the previously known layered packing, compound 4 was found to adopt an unusual layered crystal packing with arch layers alternately arranged upward or downward. It may play an important role in contributing to its superior thermal stability (350 °C), providing an enlightening thinking to design new highly thermal stable energetic materials.

Full text of DOI:10.1002/zaac.201800086

Title: An unusual layered crystal packing gives rise to a superior
thermal stability of energetic salt of 3,6-bishydrazino-1,2,4,5-
tetrazine
Authors: Gu-Dan Zhang, Zhen Wang, and Jianguo Zhang
This manuscript has been accepted after peer review and appears as an
Accepted Article online prior to editing, proofing, and formal publication
of the final Version of Record (VoR). This work is currently citable by
using the Digital Object Identifier (DOI) given below. The VoR will be
published online in Early View as soon as possible and may be different
to this Accepted Article as a result of editing. Readers should obtain
the VoR from the journal website shown below when it is published
to ensure accuracy of information. The authors are responsible for the
content of this Accepted Article.
To be cited as: Z. anorg. allg. Chem. 10.1002/zaac.201800086
Link to VoR: http://dx.doi.org/10.1002/zaac.201800086

10.1002/zaac.201800086
Zeitschrift für anorganische und allgemeine Chemie
An unusual layered crystal packing gives rise to a superior thermal
stability of energetic salt of 3,6-bishydrazino-1,2,4,5-tetrazine
Gu-Dan Zhang,[a] Zhen Wang,[a] Jian-Guo Zhang[a]
Abstract: Five energetic salts of 3,6-Bishydrazino-1,2,4,5-tetrazine (BHT) were
synthesized and fully characterized by elemental analysis, FT-IR and mass spectra.
They are (BHT)2(NTO)3 (3), (BHT)(BTT)·2H2O (4), (BHT)(DNP)2 (5), (BHT)(NATr)2
(6), (BHT)(FOX-7)2 (7), respectively. Of which two crystal structures 3 and 4 were
obtained and determined. Sensitivities towards outside stimuli and thermal behaviors
of all the compounds were investigated, besides, thermodynamics of both 3 and 4 were
calculated as well. All the compounds exhibit splendid thermal stabilities and
satisfactory sensitivities simultaneously. Notably, unlike the previously known layered
packing, compound 4 was found to adopt an unusual layered crystal packing with arch
layers alternately arranged upward or downward. It may play an important role in
o
contributing to its superior thermal stability (350 C), providing an enlightening
thinking to design new highly thermal stable energetic materials.
Introduction
Energetic materials include explosives, propellants, and pyrotechnics that are used for
a variety of military purposes and civilian applications.[1] Recently, nitrogen-rich
heterocycles are one of the high energy density materials (HEDMs) that each world
power competed on, of which two important kinds are azoles and tetrazines.[2-6] These
*
Prof. Dr. J.-G. Zhang
Fax: +86-10-68918091
E-Mail: zjgbit@bit.edu.cn
[a] State Key Laboratory of Explosion Science and Technology
Beijing Institute of Technology
Beijing 100081, P. R. China
1
This article is protected by copyright. All rights reserved.

10.1002/zaac.201800086
Zeitschrift für anorganische und allgemeine Chemie
high nitrogen content materials have a large number of N-N and C-N bonds and
therefore exhibit large positive heats of formation. Additionally, the low percentages of
C and H in these compounds have triple positive effects: (i) enhance density; (ii) allow
a good oxygen balance to be achieved easily; and (iii) produce a larger number of moles
of gaseous products per gram of the high-energy material.[1] Nowadays, there is a trend
that energetic ionic salts are becoming the research focus in the field of energetic
materials,[7-8] energetic ionic salts possess advantages over non-ionic molecules owing
to their lower vapor pressures and higher densities. Besides, tetrazine and azole based
ionic salts possess high heats of formations, the low carbon and hydrogen content rises
the oxygen balance, which makes the energetic salts very promising candidates for the
demands of new energetic materials.[9]
3,6-Bishydrazino-1,2,4,5-tetrazine (BHT, 1) was first synthesized by reacting diamino-
s-tetrazine with hydrazine hydrate.[10] In 2001, a new synthetic route for BHT using 3,6-
bis(3,5-dimethylpyrazol-1-yl)-1,2,4,5-tetrazine (BT) and hydrazine hydrate heated in
acetonitrile solvent was reported by Hiskey et al., additionally, the perchlorate and
nitrate salts of BHT were also prepared by them.[11] BHT possesses high nitrogen
content (78.9%) and positive enthalpy of formation (577.0 kJ·mol-1), along with its
good stability and reasonable alkaline concomitantly, making it a promising cation for
energetic salts.
We prepared BHT(PA)2, BHT(HTNR)2·H2O and BHT(H2TNPG)2·2H2O (where PA,
TNR and TNPG denote trinitrophenol, trinitroresorcinol and trinitrophloroglucinol,
respectively) by reacting BHT with corresponding acidic compounds directly in
2012.[12]
In 2013, several highly energetic salts of BHT were prepared and investigated by
Klapötke et al. These salts were obtained by reacting BHT·2HCl with freely soluble
salts of corresponding acidic compounds. As a result, these salts possess relatively good
properties, of which the detonation parameters of bishydrazinium-tetrazine bis (5-
nitrotetrazolate) (BHT-(NT)2) and bishydrazinium-tetrazine 4,4´,5,5´-tetranitro-2,2´-
bisimidazolate (BHT·TNBI) in terms of energetic applications were calculated using
the EXPLO5 V5.05 computer code. According to the calculate results, both of them
2
This article is protected by copyright. All rights reserved.

10.1002/zaac.201800086
Zeitschrift für anorganische und allgemeine Chemie
exhibit detonation performance commensurate with that of RDX, which gives rise to
these energetic salts of BHT as relatively good perspectives in the area of energetic
materials.[13]
Inspired by these and in order to further explore the feasibility of BHT salts being
applied as energetic materials, five brand new energetic salts of BHT were prepared,
characterized and investigated by elemental analysis, FT-IR and mass spectra herein.
All the compounds were directly synthesized via salt metathesis, including
(BHT)2(NTO)3 (3), (BHT)(BTT)·2H2O (4), (BHT)(DNP)2 (5), (BHT)(NATr)2 (6) and
(BHT)(FOX-7)2 (7), where NTO, BTT, DNP, NATr and FOX-7 denote 3-nitro-1,2,4-
triazol-5-one, 4,5-Bis(5-tetrazolyl)-1,2,3-triazole, 3,4-dinitropyrazole, 3-nitramino-
1,2,4-triazole and 1,1-diamino-2,2-dinitroethylene, respectively. Among all the
compounds, the crystal structures of 3 and 4 were obtained and investigated. All of
them are equipped with quite reasonable thermal stabilities and insensitivities towards
impact and friction. Additionally, 4 adopts an unusual layered crystal packing different
from the previously reported ways, which contributes to its superior thermal stability
with a decomposition temperature of 350 oC.
Results and Discussion
Synthesis
BHT was synthesized according to the previously known procedure.[14-15] To get the
utmost out of BHT in the subsequent salt metathesis, it was converted to
bishydrazinium-tetrazine dichloride (1:2) (BHT-2HCl, 2) based on literature,[16] too,
which is shown in Scheme 1.
As a result, the salt metathesis reactions proceeded smoothly by reacting BHT-2HCl
with sodium salts of corresponding energetic compounds to give 3-7. An overall
synthetic protocol is displayed in Scheme 2. The specified anions were synthesized as
described in the literature.[17-20]
3
This article is protected by copyright. All rights reserved.

10.1002/zaac.201800086
Zeitschrift für anorganische und allgemeine Chemie
Scheme 1. Synthetic route of BHT-2HCl.
Scheme 2. The overall synthetic protocol of the energetic salts 3-7.
4
This article is protected by copyright. All rights reserved.

10.1002/zaac.201800086
Zeitschrift für anorganische und allgemeine Chemie
Crystal Structure
The X-ray crystallographic data were determined by using a Rigaku Saturn 724+CCD
diffractometer equipped with graphite mono-chromated Mo-Kα radiation. The
structures were solved with successive Fourier difference syntheses (with SHELXS-97)
program and refined by full-matrix least squares on F2 using SHELXL-97.
Crystallographic data are summarized in Table 1. Further information regarding the
crystal-structure determinations have been deposited with the Cambridge
Crystallographic Data Centre as supplementary publication numbers.
Single crystal of compound 3 (Figure 1) was obtained successfully in the anhydrous
form, which crystallizes in the triclinic space group P-1 with one formula unit per unit
cell and a calculated density of 1.737 g·cm-3 at 293 K. The NTO anions also follow the
planar structure described previously such as DATr·NTO (where DATr denotes 3,4-
diamino-1,2,4-triazole),[21] while a twisting was observed in tetrazine ring.
Figure 1. Molecular structure of 3. Selected bond lengths (Å): C1-N2 1.341(8), C1-N3 1.331(8),
C2-N1 1.331(8), C2-N4 1.353(8), C3-N10 1.339(8), C3-N11 1.351(8), C4-N9 1.304(8), C4-N12
1.420(8), C5-O1 1.296(7), C7-O4 1.267(8), C9-O7 1.300(7); selected bond angles (°): C1-N2-N1
115.7(5), C2-N1-N2 116.4(5), C1-N3-N4 115.4(5), C2-N4-N3 118.6(5), C5-N17-N18 110.6(5), C6-
N18-N17 100.6(5), O1-C5-N17 124.9(5), O2-N20-O3 125.5(6); selected torsion angles (°): C5-
N17-N18-C6 0.1(6), C7-N21-N22-C8 0.2(6), C9-N25-N26-C10 -0.3(6), N17-N18-C6-N20
5
This article is protected by copyright. All rights reserved.

10.1002/zaac.201800086
Zeitschrift für anorganische und allgemeine Chemie
-179.4(5), C5-N19-C6-N18 0.3(7), N25-N26-C10-N27 0.0(7).
Compound 4 (Figure 2) crystallizes in the monoclinic space group P 2(1)/c with four
formula units per unit cell. The unit cell has the dimensions of a=14.4559 (12) Å,
b=6.7390 (6) Å, c=16.0941 (13) Å, β=99.105 (2) °. It crystallizes with a cell volume of
1548.1 (2) Å3 and a density of 1.645 g·cm-3 at 298 K. It was found to have an unusual,
wavelike layered crystal packing on the whole, with a pair of BHT and BTT together
as the gibbous part while another pair alongside plays the concave role. Precisely
speaking, both the gibbous and the concave parts are not genuinely concatenate.
However, both of them adopt an arch structure, upward or downward by turns, resulting
in a wavelike packing viewed as a whole, as given in Figure 3.
Figure 2. Molecular structure of 4. Selected bond lengths (Å): N1-N2 1.329(3), N1-C2 1.341(4),
N3-C3 1.341(4), C2-C3 1.407(4), C1-N4 1.320(4), C1-N7 1.326(4), C5-N12 1.340(4), C5-N15
1.378(4), C6-N13 1.315(4), C6-N14 1.369(4); selected bond angles (°): C2-N1-N2 103.0(3), N1-
N2-N3 116.2(3), C4-N8-N9 104.7(3), N4-C1-N7 108.9(3), N13-C6-N14 126.9(3), N13-C6-N18
119.5(3), C6-N13-N12 117.0(3); selected torsion angles (°): C2-N1-N2-N3 0.1(4), N1-N2-N3-C3
0.7(4), C1-N4-N5-N6 -0.6(4), N4-N5-N6-N7 0.9(4), C4-N8-N9-N10 -0.4(4), N8-N9-N10-N11
0.2(4), C5-N12-N13-C6 -0.1(4), C6-N14-N15-C5 -1.8(4), N19-N18-C6-N14 164.9(3).
6
This article is protected by copyright. All rights reserved.

10.1002/zaac.201800086
Zeitschrift für anorganische und allgemeine Chemie
Table 1. Crystallographic data of compound 3 and 4
Compound
Formula
BHT2-(NTO)3 (3)
C10H21N28O9
677.55
BHT-BTT·2H2O (4)
C6H13N19O2
383.35
FW(g·mol-1)
Crystal system
Space group
Triclinic
Monoclinic
P2(1)/c
P1
Crystal size(mm)
a (Å)
0.15 x 0.10 x 0.06
6.8283(6)
0.35 x 0.11 x 0.05
14.4559(12)
6.7390(6)
b (Å)
6.9278(6)
c (Å)
14.3445(14)
80.315(2)
16.0941(13)
α (°)
β (°)
76.6020(10)
82.666(2)
γ (°)
V (Å3)
647.90(10)
1548.1(2)
4
Z
1
ρ (g·cm-1)
1.737
1.645
μ (mm-1)
0.150
0.133
F(000)
349
792
λMoKα(Å)
0.71073
0.71073
298(2)
2.56-25.02
7437
T(K)
293(2)
θ (°)
2.95-25.02
3319
Reflection collected
Independent reflection [Rint]
R1, wR2 [I > 2σ (I)]
R1, wR2 (all)
Δρmax, Δρmin (e·Å −3)
CCDC No.
2766 [R(int) = 0.0251]
0.0508, 0.1385
0.0618, 0.1464
0.389, -0.326
1533133
2716 [R(int) = 0.0730]
0.0585, 0.1254
0.1129, 0.1404
0.331, -0.301
1560575
7
This article is protected by copyright. All rights reserved.

10.1002/zaac.201800086
Zeitschrift für anorganische und allgemeine Chemie
(a)
(b)
Figure 3. Ball-and-stick packing diagrams of compound 4 viewed down the a axis (a) and c axis
(b), respectively.
In the packing diagram of both 3 and 4, many strong interactions derived from both
intermolecular and intramolecular hydrogen bonding are observed, also contributing to
enhancing the stabilities.
Sensitivities and Thermal Stabilities
Values of sensitivities towards impact and friction stimuli were obtained according to
BAM standard as given in Table 2. All the compounds are insensitive towards friction,
8
This article is protected by copyright. All rights reserved.

10.1002/zaac.201800086
Zeitschrift für anorganische und allgemeine Chemie
even the lowest value reaches up to 240 N. Resulting from the existence of nitroamino
group probably, compound 6 possesses the highest impact sensitivity (6 J). Salt 3, 5 and
7 (12-15 J) are sensitive to impact, whereas 1, 2 and 4 (20-30 J) are less sensitive.
Thermal stabilities of all compounds described in this work were investigated via
differential scanning calorimetry(DSC). As shown in Table 2, the decomposition
o
temperatures of all compounds range from 144 to 350 C, exhibiting quite favorable
thermal stability. Only compound 3 has an endothermic peak, maybe corresponding to
the melting process. The endothermic event of water loss is absent in the DSC curve of
4, which indicates that either water is released during the decomposition process, or
crystal water is lost over the time during the storage of this material at ambient
temperature. It is important to note that most of them possess thermal behavior either
comparable to RDX (204 oC) or better than it, probably owing to the salt formation.
Table 2. Sensitivities and decomposition temperatures of the compounds
Compound
IS(J)
30
28
12
20
15
6
FS(N)
>360
>360
324
Tdec(°C)
144
1
2
3
4
5
6
7
193
157
>360
>360
240
350
243
217
14
360
252
Additionally, non-isothermal kinetic calculations of compound 3 and 4 were done by
using the temperature data of the first exothermic peaks of the DSC curves. The DSC
curves were obtained based on four different heating rates (5,10,15 and 20 K·min-1).
Kissinger's method[22] and Ozawa–Doyle's method[23] were used, and equations of the
two methods are shown as follows, respectively:
휑
퐸
푎
ln 푇 = ln 퐴퐸푅
−
(1)
2
푅푇
푚
푚
푎
9
This article is protected by copyright. All rights reserved.

10.1002/zaac.201800086
Zeitschrift für anorganische und allgemeine Chemie
lg 휑 + 0.4567퐸 = 퐶
(2)
푎
푅푇
푚
where φ is the heating rate, K·min-1; R is the universal gas constant, 8.314 J·(mol·K)-1;
Tm is the temperature of the exothermic peak, K; Ea is the apparent activation energy,
kJ·mol-1; A is the pre-exponential factor, s-1; and C is a constant.
Non-isothermal kinetic parameters of compound 3 and 4 are given in Table 3.
Apparent activation energy can be approximated to reflect the difficult degree of the
thermal decomposition of the compound. The results using both methods correspond
well with each other and the Arrhenius equation can be expressed as follow:
3
ln푘 = 23.46 − 99.8×10
(3) for compound 3
(4) for compound 4
푅푇
3
ln푘 = 48.86 − 274.6×10
푅푇
Which can be used to estimate the rate constants of the initial thermal decomposition
process of the compound 3 and 4. Compound 4 possesses high apparent activation
energy, which reveals a very good thermal stability.
Table 3. Non-isothermal kinetic parameters of compound 3 and 4
Kissinger’s method
Ozawa–Doyle’s method
Parameters
3
4
3
4
Apparent activation energy Ea (kJ·mol-1)
Pre-exponential factor lg A
99.8
274.6
101.7
‒
270.9
‒
10.19
-0.9914
0.09020
21.22
The linear correlation coefficient
Standard deviation
-0.9968
0.05685
-0.9924
0.03929
-0.9970
0.02471
It is noteworthy that compound 4 is featured with both superior thermal behavior (350
oC) and satisfying sensitivities (IS: 20 J, FS: >360 N), which highlights it as a potential
stable explosive. It appears that the strong interactions born of intermolecular and
intramolecular hydrogen bonding as well as the wavelike layered crystal packing
together account for its high thermal stability and insensitivities. As a whole, the
wavelike construction makes it easy to circulate the energy due to flexible up-and-down
movements, in case of heat accumulation; as far as each individual layer concerned, the
10
This article is protected by copyright. All rights reserved.

10.1002/zaac.201800086
Zeitschrift für anorganische und allgemeine Chemie
arch structure is always favored in architecture because it is characteristic of
distributing the load to different parts so as to avoid localized stress concentration issue,
herein it comes into play, resulting in the satisfying insensitivities of compound 4 to
some extent. What an ingenious way of different things adapting themselves to this
complicated world spontaneously. This kind of layer stacking mode with arch layers
alternately arranged may provide some enlightening thinking to design new highly
thermal stable and insensitive energetic materials.
The heat of formation (ΔfH°(s,M)) of compound 3 was determined by using oxygen-
bomb calorimeter, and the molar standard enthalpies of formation (ΔHm) was calculated
to be -261.1 kJ·mol-1, then the detonation parameters of compound 3 were calculated
based on the values of density and the heat of formation using the EXPLO5 V5.05
computer code. The results are listed in Table 4.
Table 4. Detonation parameters of compound 3 by EXPLO5 V5.05
Compound 3
VDet./ m·s-1 a
TDet./K b
7779
2117.98
21.40
PCJ/GPa c
HDet./kJ·Kg-1 d
-2536.39
Vg/dm3·Kg-1 e
844.06
a
b
c
d
e
Detonation velocity; Detonation temperature; Detonation pressure; Heat of detonation;
Volume of gas at STP.
Compound 3 exhibits a moderate detonation velocity of 7800 m·s-1 approximately,
keeping a reasonable balance between energy and safety in consideration of its
relatively low sensitivities towards mechanical stimuli, which supports its application
potential.
Conclusion
In summary, five salts of 3,6-bishydrazinium-1,2,4,5-tetrazine (BHT) were synthesized
and fully characterized by elemental analysis, FT-IR and mass spectra, of which two
11
This article is protected by copyright. All rights reserved.

10.1002/zaac.201800086
Zeitschrift für anorganische und allgemeine Chemie
crystal structures (BHT2-(NTO)3 (3) and BHT-BTT·2H2O (4)) were obtained and
investigated. Besides acceptable sensitivities, all compounds display splendid thermal
behavior simultaneously, with most of them being comparable to RDX if not better,
maybe as a consequence of salt formation. The thermodynamics parameters of 3 and 4
were calculated via Kissinger's method and Ozawa–Doyle's method.
Compound 3 keeps a reasonable balance between energetic performance and safety,
showing the application potential. Compound 4 is featured with both high thermal
stability and insensitivities. The observed strong interactions and arch layer stacking
are likely to contribute to its stability and insensitivities, providing a new thinking to
design new highly stable energetic materials.
Experimental Section
Synthesis of BHT2-(NTO)3 (3)
Sodium 3-nitro-1,2,4-triazolate-5-one (0.304g, 2mmol) was dissolved in water (5mL).
This solution was added to a stirred solution of 3,6-bishydrazinium-1,2,4,5-tetrazine
dichloride (0.215g, 1mmol) in water (5mL). The mixture was stirred at ambient
temperature and was then stored at 2 °C for 24h. Afterwards dark red crystals were
filtered off.
EA: found(calc): C 17.65 (17.73), H 3.18 (3.10), N 57.79 (57.90); IR (KBr, cm-1):
ν=3319, 2738, 1615, 1502, 1350, 1303, 1055, 779, 631, 605; Mass spec:
259.15[2C2H2N4O3].
Synthesis of BHT-BTT (4)
Sodium 4,5-Bis(tetrazol-5-yl)-1,2,3-triazolate (0.227g, 1mmol) was dissolved in water
(10mL). This solution was added to a stirred solution of 3,6-bishydrazinium-1,2,4,5-
tetrazine dichloride (0.215g, 1mmol) in water (5mL). The mixture was stirred at
ambient temperature and was then stored at 2 °C for 24h. Afterwards light orange
crystals were filtered off.
EA: found(calc): C 18.87 (18.80), H 3.44 (3.39), N 69.37 (69.45); IR (KBr, cm-1):
ν=3502, 3382, 3290, 3025, 1846, 1656, 1587, 1447, 1210, 1058, 995, 695, 586; Mass
12
This article is protected by copyright. All rights reserved.

10.1002/zaac.201800086
Zeitschrift für anorganische und allgemeine Chemie
spec: 347.7.
Synthesis of BHT-(DNP)2 (5)
Sodium 3,4-dinitro-pyrazolate (0.36g, 2mmol) was dissolved in water (5mL). This
solution was added to a stirred solution of 3,6-bishydrazinium-1,2,4,5-tetrazine
dichloride (0.215g, 1mmol) in water (5mL). A yellow powder precipitated suddenly.
The powder was filtered off, washed with cold water and dried.
EA: found(calc): C 21.12 (20.96), H 2.27 (2.18), N 48.83 (48.91); IR (KBr, cm-1):
ν=3301, 3216, 3008, 2931, 1643, 1535, 1453, 1056, 1001, 938, 744, 563; Mass spec:
-
+
157.10[C3HN4O4 ], 143.05[C2H7N8 ].
Synthesis of BHT-(NATr)2 (6)
Sodium 3-nitroamino-1,2,4-triazolate (0.302g, 2mmol) was dissolved in water (5mL).
This solution was added to a stirred solution of 3,6-bishydrazinium-1,2,4,5-tetrazine
dichloride (0.215g, 1mmol) in water (5mL). A brown powder precipitated suddenly.
The powder was filtered off, washed with cold water and dried.
EA: found(calc): C 18.08 (18.00), H 3.11 (3.00), N 62.92 (63.00); IR (KBr, cm-1):
ν=3414, 3269, 3161, 2926, 1598, 1535, 1467, 1390, 1327, 1241, 1051, 952, 771, 708;
-
Mass spec: 128.15[C2H2N5O2 ].
Synthesis of BHT-(FOX-7)2 (7)
Sodium 1,1-diamino-2,2-dinitroethylene (0.34g, 2mmol) was dissolved in water (5mL).
This solution was added to a stirred solution of 3,6-bishydrazinium-1,2,4,5-tetrazine
dichloride (0.215g, 1mmol) in water (5mL). A yellow brown powder precipitated
suddenly. The powder was filtered off, washed with cold water and dried.
EA: found(calc): C 16.51 (16.44), H 3.26 (3.20), N 51.08 (51.14); IR (KBr, cm-1):
ν=3406, 3322, 3296, 1625, 1500, 1468, 1389, 1193, 1159, 1136, 1018, 753, 623; Mass
-
spec: 146.70[C2H3N4O4 ].
Acknowledgements
The supports of the 111 project (G2017001) in China and State Key Laboratory of
Explosion Science and Technology (YBKT16-04 and YBKT16-15) are gratefully
13
This article is protected by copyright. All rights reserved.

10.1002/zaac.201800086
Zeitschrift für anorganische und allgemeine Chemie
acknowledged.
Keywords: 3,6-Bishydrazino-1,2,4,5-tetrazine ⋅ Thermal stability ⋅ Sensitivity ⋅
Layered crystal packing
References
[1] H. Gao, J. M. Shreeve, Chem. Rev. 2011, 111, 7377-7436.
[2] P. Yin, C. He, J. M. Shreeve, J. Mater. Chem. A. 2016, 4, 1514-1519.
[3] D. Fischer, T. M. Klapötke, J. Stierstorfer, N. Szimhardt, Chem. Eur. J. 2016, 22, 4966-4970.
[4] D. E. Chavez, D. A. Parrish, L. Mitchell, Angew. Chem. Int. Ed. 2016, 55, 8666-8669.
[5] C. He, J. M. Shreeve, Angew. Chem. Int. Ed. 2015, 54, 6260-6264.
[6] D. Zhao, M. Lv, C. Cai, Propellants Explos. Pyrotech. 2015, 40, 627-631.
[7] J.-T. Wu, J.-G. Zhang, J. Qin, X. Yin, L. Wu, Z. Anorg. Allg. Chem. 2016, 642, 409-413.
[8] T. M. Klapötke, F. Mieskes, J. Stierstorfer, M. Weyrauther, Propellants Explos. Pyrotech. 2016,
41, 217-222.
[9] Z. Wang, J.-G. Zhang, J.-T. Wu, X. Yin, T.-L. Zhang, RSC Adv. 2016, 6, 44742-44748.
[10] H. J. Marcus, A. Remanick, J. Org. Chem. 1963, 28, 2372-2735.
[11] M. A. Hiskey, D. E. Chavez, D. L. Naud, U.S. Pat. 6214139 B1, 2001.
[12] J.-G. Zhang, Y.-H. Liang, J.-L. Feng, K. Wang, T.-L. Zhang, Z.-N. Zhou, L. Yang, Z. Anorg.
Allg. Chem. 2012, 638, 1212-1218.
[13] T. M. Klapötke, A. Preimesser, S. Schedlbauer, J. Stierstorfer, Cent. Eur. J. Energ. Mater. 2013,
10, 151-170.
[14] M. D. Coburn, G. A. Buntain, B. W. Harris, M. A. Hiskey, K.-Y. Lee, D. G. Ott, J. Heterocyclic
Chem. 1991, 28, 2049-2050.
[15] D. E. Chavez, M. A. Hiskey, J. Heterocycl. Chem. 1998, 35, 1329-1332.
[16] H. J. Marcus, U.S. Pat. 3244702, 1966.
[17] A. Saikia, R. Sivabalan, G. M. Gore, A. K. Sikder, J. Sci. Ind. Res. 2014, 73, 485-488.
[18] A. A. Dippold, Dániel. Izsák, T. M. Klapötke, C. Pflüger, Chem. – Eur. J. 2016, 22, 1768-1778.
[19] P. Ravi, J. Mol. Struct. 2015, 1079, 433-447.
[20] T. P. Kofman, G. Y. Kartseva, M. B. Shcherbinin, Russ. J. Org. Chem. 2002, 38, 1343-1350.
14
This article is protected by copyright. All rights reserved.

10.1002/zaac.201800086
Zeitschrift für anorganische und allgemeine Chemie
[21] J.-T. Wu, J.-G. Zhang, X. Yin, M. Sun, T.-L. Zhang, Z. Anorg. Allg. Chem. 2013, 639, 2354-
2358.
[22] H. E. Kissinger, Anal. Chem. 1957, 29, 1702-1706.
[23] T. Ozawa, Bull. Chem. Soc. Jpn. 1965, 38, 1881-1886.
15
This article is protected by copyright. All rights reserved.