Energetic hydrazine-based salts with nitrogen-rich and oxidizing anions

Article abstract of DOI:10.1002/asia.201200437

1,1,1-Trimethylhydrazinium iodide ([(CH₃)₃N-NH ₂]I, 1) was reacted with a silver salt to form the corresponding nitrate ([(CH₃)₃N-NH₂][NO₃], 2), perchlorate ([(CH₃)₃N-NH₂][ClO₄], 3), azide ([(CH₃)₃N-NH₂][N₃], 4), 5-amino-1H-tetrazolate ([(CH₃)₃N-NH₂][H ₂N-CN₄], 5), and sulfate ([(CH₃) ₃N-NH₂]₂[SO₄]·2H ₂O, 6·2H₂O) salts. The metathesis reaction of compound 6·2H₂O with barium salts led to the formation of the corresponding picrate ([(CH₃)₃N-NH₂][(NO ₂)₃Ph-O], 7), dinitramide ([(CH₃) ₃N-NH₂][N(NO₂)₂], 8), 5-nitrotetrazolate ([(CH₃)₃N-NH₂][O ₂N-CN₄], 9), and nitroformiate ([(CH₃) ₃N-NH₂][C(NO₂)₃], 10) salts. Compounds 1-10 were characterized by elemental analysis, mass spectrometry, infrared/Raman spectroscopy, and multinuclear NMR spectroscopy (¹H, ¹³C, and ¹⁵N). Additionally, compounds 1, 6, and 7 were also characterized by low-temperature X-ray diffraction techniques (XRD). Ba(NH₄)(NT)₃ (NT=5-nitrotetrazole anion) was accidentally obtained during the synthesis of the 5-nitrotetrazole salt 9 and was also characterized by low-temperature XRD. Furthermore, the structure of the [(CH₃)₃N-NH₂]⁺ cation was optimized using the B3LYP method and used to calculate its vibrational frequencies, NBO charges, and electronic energy. Differential scanning calorimetry (DSC) was used to assess the thermal stabilities of salts 2-5 and 7-10, and the sensitivities of the materials towards classical stimuli were estimated by submitting the compounds to standard (BAM) tests. Lastly, we computed the performance parameters (detonation pressures/velocities and specific impulses) and the decomposition gases of compounds 2-5 and 7-10 and those of their oxygen-balanced mixtures with an oxidizer. Copyright

Full text of DOI:10.1002/asia.201200437

DOI: 10.1002/asia.201200437
Energetic Hydrazine-Based Salts with Nitrogen-Rich and Oxidizing Anions
Carles Mirꢀ Sabatꢁ,*[a] Henri Delalu,[a] and Erwann Jeanneau[b]
À
Abstract: 1,1,1-Trimethylhydrazinium
were characterized by elemental analy-
sis, mass spectrometry, infrared/Raman
spectroscopy, and multinuclear NMR
spectroscopy (1H, 13C, and 15N). Addi-
tionally, compounds 1, 6, and 7 were
also characterized by low-temperature
X-ray diffraction techniques (XRD).
more, the structure of the [(CH3)3N
NH2]+ cation was optimized using the
B3LYP method and used to calculate
its vibrational frequencies, NBO charg-
es, and electronic energy. Differential
scanning calorimetry (DSC) was used
to assess the thermal stabilities of salts
2–5 and 7–10, and the sensitivities of
the materials towards classical stimuli
were estimated by submitting the com-
pounds to standard (BAM) tests.
Lastly, we computed the performance
parameters (detonation pressures/ve-
locities and specific impulses) and the
decomposition gases of compounds 2–5
and 7–10 and those of their oxygen-bal-
anced mixtures with an oxidizer.
À
iodide ([(CH3)3N NH2]I, 1) was react-
ed with a silver salt to form the corre-
À
sponding
nitrate
([(CH3)3N NH2]
À
A
À
[ClO4], 3), azide ([(CH3)3N NH2][N3],
4), 5-amino-1H-tetrazolate ([(CH3)3N
À
À
NH2]
[H2N CN4], 5), and sulfate
BaACHTGUNTREN(NUG NH4)(NT)3 (NT=5-nitrotetrazole
À
([(CH3)3N NH2]
[SO4]·2H2O, 6·2H2O)
anion) was accidentally obtained
during the synthesis of the 5-nitrotetra-
zole salt 9 and was also characterized
by low-temperature XRD. Further-
salts. The metathesis reaction of com-
pound 6·2H2O with barium salts led to
the formation of the corresponding pic-
À
rate ([(CH3)3N NH2]ACHTNUGTRNEUNG[(NO2)3Ph-O], 7),
À
dinitramide
(NO2)2],
([(CH3)3N NH2][N-
5-nitrotetrazolate
À
Keywords: crystal
density functional calculations
structures
·
·
N
8),
À
([(CH3)3N NH2]
nitroformiate
H
ACHTUNGTRENNUNG
energetic compounds · hydrazines ·
NMR (multinuclear) spectroscopy
À
([(CH3)3N NH2][C-
(NO2)3], 10) salts. Compounds 1–10
Introduction
and its liquid covalent derivatives are highly toxic and vola-
tile, and they can form explosive mixtures with air.[5] In this
context, salt-based energetic materials are at the center of
attention in view of their potential to replace liquid hydra-
zines[6–9] due to their lower vapor pressure (which essentially
eliminates the risk of exposure through inhalation), their
higher density (which is directly proportional to the energet-
ic performance of the materials), and their high thermal and
chemical stabilities.[6–13]
Liquid hydrazines (e.g., hydrazine, monomethylhydrazine,
and 1,1-dimethylhydrazine) are widely used in rocket fuels
in combination with strong oxidizers (e.g., nitrogen tetroxide
(NTO), white fuming nitric acid (WFNA), or red fuming
nitric acid (RFNA)) (Figure 1).[1–4] Unfortunately, hydrazine
Recently, we reported on a series of energetic salts based
on the 1,2-dimethylhydrazine cation, which have low sensi-
tivities to classical stimuli, are less toxic than liquid hydra-
zines, perform better than 1,3,5-trinitrotoluene (TNT), and
have good thermal and chemical stabilities.[14] Also recently,
a series of energetic salts based on the [(CH3)2N(R)NH2]+
cation (R=amino and alkyl groups) were reported.[8,9,15]
The high thermal robustness and interesting energetic prop-
Figure 1. Commonly used oxidizers: nitrogen tetroxide (NTO), white/red
fuming nitric acid (WFNA/RFNA), ammonium nitrate (AN), and ammo-
nium dinitramide (ADN).
[a] Dr. C. M. Sabatꢀ, Dr. H. Delalu
Laboratoire Hydrazines et Composꢀs ðnergꢀtiques Polyazotꢀs
UMR 5278/CNRS/UCBL/CNES/SME-SAFRAN
Universitꢀ Claude Bernard Lyon 1
3ꢁ ꢀtage, 22, av. Gaston Berger, 69622 Villeurbanne (France)
Fax : (+33)472-431-291
erties of this type of materials attracted our attention to the
+
À
[(CH3)3N NH2] cation. The synthesis of this cation was re-
ported as early as 1957 by Sisler and Omietanski[16] by alky-
lation of the corresponding hydrazine. The first report on an
+
E-mail: carlos.miro-sabate@univ-lyon1.fr
À
energetic salt of the [(CH3)3N NH2] cation was that of the
[b] Dr. E. Jeanneau
nitrate salt, which appeared as late as 1992. This compound
was synthesized by amination of trimethylamine using hy-
droxylamine-O-sulfonic acid and was only characterized by
NMR and infrared spectroscopies.[17] Reports on the azide
and azobistetrazolate salts followed in 1999 and 2001, re-
spectively.[18] Although both compounds were properly char-
Centre de Diffractomꢀtrie Henri Longchambon
Universitꢀ Claude Bernard Lyon 1
43 Bd. du 11 novembre 1918, 69622 Villeurbanne (France)
Fax : (+33)472-431-160
Supporting information for this article is available on the WWW
under http://dx.doi.org/10.1002/asia.201200437.
Chem. Asian J. 2012, 00, 0 – 0
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FULL PAPER
acterized, detailed information about their thermal stabili-
ties, their sensitivities towards classical stimuli, and their en-
ergetic performances appears to be missing in the literature.
Lastly, the dicyanamide and nitrocyanamide salts were re-
cently investigated by Shreeve et al.[9] The latter compounds
were characterized by analytical and spectroscopic methods,
and their energetic properties suggest that these materials
might have potential as hypergolic ionic liquids. In this con-
text, we would like to present our results on the synthesis,
the 5-nitrotetrazole anion (i.e., BaACHTNGUETRNU(NG NH4)(NT)3, NT=5-nitro-
tetrazole anion) were obtained (see X-ray discussion
below).
Spectroscopic Analysis
The most intense bands in the Raman spectra of salts 2–10
correspond to the vibration modes of the anions and are ob-
ACTHNUTRGNEUNG
served at 1052 cmÀ1 (nitrate, n(NO3)),[19] 935 and 462 cmÀ1
characterization, and energetic properties of energetic salts
(ClO4)),[20] 1328 cmÀ1 (azide,
(perchlorate, nACTHNGUTREN(NUG ClO4) and dACHTNUGTRENNUNG
+
of the [(CH3)3N NH2] cation with nitrogen-rich and oxi-
dizing anions.
n(N3)),[21] 749 and 1046 cmÀ1 (5-amino-1H-tetrazolate, t-
À
À
(NH2) and n(Nring
N
ring)),[22] 978 cmÀ1 (sulfate, n
(SO4)),[23]
(NO2)),[24] 827
(NO2)),[21] 1024,
(NO2) and n
(NO2)),[25]
and 868 and 1271/1378 cmÀ1 (nitroformiate, d
(NO2) and n-
(NO2)).[26] Table S1in the Supporting Information contains
1309, 1329, 1347, and 1365 cmÀ1 (picrate, n
G
and 1328 cmÀ1 (dinitramide, d
1060, and 1423 (5-nitrotetrazolate, d
ACHUTGTNERNNUG(NO2) and nACHTGNUTRENNUNG
Results and Discussion
A
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
Synthesis
AHCTUNGTRENNUNG
1,1-Dimethylhydrazine was reacted with methyl iodide in
THF according to a recently published procedure[9] to form
a summary of the (scaled) calculated frequencies with infra-
red intensities and Raman scattering activities along with
À
the corresponding iodide salt ([(CH3)3N NH2]I, 1,
Scheme 1). Compound 1 was then reacted with silver salts in
the experimental averaged values of the salts of the
+
À
[(CH3)3N NH2] cation studied in this work. The most in-
À
water or alcohol, leading to the formation of the nitrate
[NO3], 2), perchlorate ([(CH3)3N NH2]
[ClO4], 3), azide ([(CH3)3N NH2][N3], 4), 5-amino-1H-tetra-
[H2N CN4], 5), and sulfate
[SO4]·2H2O, 6·2H2O) salts. Subsequently,
compound 6·2H2O was reacted in water or alcohol with
barium salts to form the corresponding picrate ([(CH3)3N
tense bands for the vibrational modes of the [(CH3)3N
([(CH3)3N NH2]
R
G
NH2]+ cation in the Raman spectra are the C N and N N
stretching modes, found experimentally in the range 750 to
945 cmÀ1.
À
À
À
À
À
À
À
zolate ([(CH3)3N NH2]
N
À
([(CH3)3N NH2]
2A
On the other hand, the bands of the anion in the infrared
spectra of salts 2–10 are obscured by the vibrational modes
+
À
À
of the [(CH3)3N NH2] cation. These spectra are dominated
À1
À
À
À
NH2]
U
[(NO2)3Ph O], 7), dinitramide ([(CH3)3N NH2][N-
by strong C N stretching bands at approximately 950 cm
(NO2)2], 8), 5-nitrotetrazolate ([(CH3)3N NH2]
[O2N CN4],
(NO2)3], 10) salts.
and signals of medium intensity at 1060 and 1150 cmÀ1 (tor-
À
À
À
À
À
9), and nitroformiate ([(CH3)3N NH2][C
U
sion modes of the NH2 and CH3 groups). The rest of the
bands have lower intensities and can be assigned as follows:
Except for salts 7 and 10, which are bright yellow com-
pounds, the remainder of the materials are colorless. Fur-
thermore, salts 1–10 are stable to hydrolysis and are readily
soluble in water, DMSO, ethanol, and acetone, less soluble
in solvents such as isopropanol and THF, and insoluble in
dichloromethane and ether. Lastly, during the synthesis of
salt 9 single crystals of the ammonium/barium double salt of
3270–3345 cmÀ1 ( NH2 group symmetric and asymmetric
À
stretches), 2965–3145 cmÀ1 ( CH3 group symmetric and
À
asymmetric stretches), 1475–1615 cmÀ1 (in-plane bending
modes of the NH2 and CH3 groups), 1315–1425 cmÀ1
À
À
À
À
(out-of-plane bending modes of the NH2 and CH3
groups), 1060–1275 cmÀ1 (torsion modes of the NH2 and
À
À
CH3 groups), and <500 cmÀ1
(C-N-N and C-N-C in-plane
bending modes).[27]
The
structure
À
of
the
+
[(CH3)3N NH2]
cation was
also characterized in solution
using multinuclear NMR spec-
troscopy (1H, 13C, and 15N).
Table 1 shows a summary of the
NMR
measurements.
The
1H NMR spectra of salts 1–10
(in [D6]DMSO) show two reso-
À
nances: that of the
CH3
groups
at
approximately
À
3.25 ppm and that of the NH2
groups, which appear as broad
signals in the range between
about 6.00 and 6.20 ppm. In the
À
13C NMR spectra, the
CH3
+
À
Scheme 1. Synthesis of salts of the [(CH3)3N NH2] cation.
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Energetic Hydrazine-Based Salts with Nitrogen-Rich and Oxidizing Anions
15
Table 1. 1H, 13C, and N NMR chemical shifts (ppm) of the [(CH3)3N
À
NH2]+ cation in compounds 1–10.[a]
1H NMR
13C NMR
15N NMR[b]
À
CH3
À
NH2
À
CH3
À
N
À
NH2
G
1
2
3
3.28
3.26
3.24
6.10
6.11
6.04
57.2
57.2
57.3
+79.7
+128.8
(1JN-H=67.7 Hz)
4
5
6
7
8
9
10
3.22
3.26
3.25
3.25
3.25
3.26
3.25
6.22
6.11
6.09
6.09
6.07
6.10
6.09
57.2
57.2
57.2
57.2
57.3
57.3
57.2
Figure 3. Optimized geometry and natural bond orbital (NBO) charge
+
À
distribution of the [(CH3)3N NH2] cation (B3LYP/6-31+G
N
[a] in [D6]DMSO; [b] ammonia was used as an external standard.
The disorder found in the crystal structure of salt 1 ac-
counts for the significant differences in the bond lengths of
this compound with the analogous distances in salts 6 and 7.
With the exception of compound 1, the bond lengths in the
groups of compounds 1–10 show very consistent resonances
at about 57.2 ppm. Additionally, we measured the 15N NMR
À
spectrum of the perchlorate salt (3) as a representative ex-
cation in the crystal structures of the salts of the [(CH3)3N
+
ample of a salt containing the [(CH3)3N NH2] cation
NH2]+ cation are in the expected range for N N and C N
single bonds, while the bond angles are close to the expected
109.58 for a tetrahedral geometry (Table 2). The computed
À
À
À
À
N
(Figure 2). The nitrogen atom of the
G
nates at +79.7 ppm (ammonia as external standard), and no
À
multiplicity was observed, whereas the NH2 group reso-
nates at +128.8 ppm with a coupling constant JNÀH of
67.7 Hz.
values (B3LYP and MP2) for the gas-phase structure of the
1
+
À
[(CH3)3N NH2] cation are in good agreement with those
of the solid state. Compound 1 crystallizes in a tetragonal
cell (Figure 4). The substituents
+
À
around the [(CH3)3N NH2]
cation are disordered so that
the probability of each substitu-
À
ent being
75%, whereas that of it being
a
CH3 group is
À
a
NH2 group is 25%. The
structure does not contain any
significant hydrogen bonds;
however, long contacts between
À
the hydrogen atoms of the
NH2 groups and the iodine
anions
exist
(N···I=
3.677(15) ꢃ). These contacts
describe ring graph sets[29] with
the label R1,2(12) and are
shown in Figure 4.
Figure 2. 15N NMR spectrum of compound 3 in [D6]DMSO (ammonia as an external reference).
NBO Analysis and Crystal Structures
Table 2. Selected bond lengths (ꢃ) and angles (8) (from the X-ray crystal structures)
+
À
The optimized structure of the [(CH3)3N NH2]
cation (obtained from density functional theory cal-
culations at the B3LYP/6-31+G(d,p) level) was
+
À
for salts of the [(CH3)3N NH2] cation and comparison with the computed values
(from chemical quantum calculations).[a]
AHCTUNGTRENNUNG
Parameter
1
6 (A)
6 (B)
7
B3LYP
MP2
used for natural bond orbital (NBO) calculations
(Figure 3).[28] The amino group nitrogen atom (N1)
has the largest negative charge (À0.693e) and is in-
volved in strong hydrogen bonding to anions and
cations (see the discussion below). On the other
hand, the ammonium nitrogen atom bears the
lowest negative charge (ca. À0.182e). Lastly, the
three methyl group carbon atoms have comparable
negative charges of about À0.485e.
À
N1 N2
1.556(7)
1.463(6)
1.463(6)
1.463(6)
1.446(8)
1.521(11)
1.491(10)
1.475(9)
1.447(7)
1.504(8)
1.495(10)
1.467(10)
1.448(2)
1.501(3)
1.498(3)
1.487(3)
1.452
1.508
1.507
1.510
106.5
106.5
113.3
109.8
110.3
110.3
1.451
1.501
1.501
1.502
À
N2 C3
À
N2 C4
À
N2 C5
À
À
N1 N2 C3 105.7(1)
106.9(6)
107.7(6)
107.2(2)
106.7
À
À
N1 N2 C4 111.2(1)
107.9(6)
109.4(7)
113.1(6)
110.5(7)
108.8(6)
108.1(6)
110.1(6)
110.9(5)
110.2(6)
109.8(6)
109.0(2)
110.0(2)
110.4(2)
110.3(2)
109.6(2)
106.7
113.1
109.6
110.3
110.3
À
À
C3 N2 C4 108.2(1)
À
À
N1 N2 C5 111.2(1)
À
À
C3 N2 C5 108.2(1)
À
À
C4 N2 C5 111.9(1)
[a] See Figure 3 for the labeling scheme.
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Carles Mirꢄ Sabatꢀ et al.
FULL PAPER
and R2,2(8) ring graph sets. The three types of ring graph
sets found in the structure of 6·2H2O are shown in Figure 5.
For example, the R2,2(8) ring patterns are formed by two
hydrogen bonds between one cation and two oxygen atoms
of the same anion (C17···O4=3.242(9) and N15···O2=
3.053(9) ꢃ), and the R1,2(6) patterns involve the combina-
tion of two hydrogen bonds between one cation and the
same oxygen atom of the anion (C17···O5i =3.315(9) and
C18···O5i =3.272(9) ꢃ; symmetry code: (i) À0.5+x, 1.5Ày,
À0.5+z).
Figure 6 shows a view of the unit cell of compound
6·2H2O along the a-axis with the hydrogen bonding (dotted
lines). One of the two molecules of water of crystallization
is involved in hydrogen bonding, whereas the other one
does not participate in any significant interaction and simply
occupies the voids between cations. The C1,2(6) and
C2,2(X) (X=6, 8) infinite chains mentioned above extend
along the c-axis and keep the structure together.
Figure 4. View along the c-axis of the unit cell of compound 1 with the
iodine–hydrogen contacts (dotted lines). The substituents around the
+
À
À
À
[(CH3)3N NH2] cation are disordered (occupancy: 75/25% ( CH3/
NH2)).
+
À
The sulfate salt of the [(CH3)3N NH2] cation formed as
a dihydrate (6·2H2O). In the solid state, the compound is in-
À
À
volved in four unclassical C O and seven classical N O and
À
O O hydrogen bonds (Table S3 in the Supporting Informa-
tion), which form D1,1(2) dimeric graph-sets (primary
level). As shown in Figure 5, the oxygen atoms of the sulfate
anions are involved in hydrogen bonding to the cations and
to the molecules of water of crystallization. At the secon-
dary level, these hydrogen bonds describe dimeric patters of
the type D1,2(3) and D2,2(5), chain motifs with the descrip-
tors C1,2(6) and C2,2(X) (X=6, 8), and R1,2(6), R2,1(4),
Figure 6. View along the a-axis of the unit cell of compound 6·2H2O with
the hydrogen bonding (dotted lines).
Compound 7 crystallizes as the anhydrous material with
one cation and one anion in the asymmetric unit. The com-
pound is involved in the formation of one classical N···O
and five unclassical C···O hydrogen bonds. At the primary
level, only D1,1(2) dimeric interactions are formed, which
combine at the secondary level to form chain patterns of the
type C2,2(X) (X=10, 12) and ring graph sets with the labels
R1,2(6), R2,2(X) (X=8, 10), R2,4(X) (X=8, 12), and
R4,4(X) (X=16, 20, 24). Figure 7 shows some of the ring
hydrogen-bonding networks found in the structure of the
compound. For example, the methyl groups of two cations
interact with the oxygen atoms of two anions (C4···O21i =
2.490(2) and C4···O21iii =2.531(2) ꢃ; symmetry codes:
(i) Àx, 2Ày, 2Àz; (iii) x, y, À1+z), forming R2,4(8) graph
sets, and one of the unclassical hydrogen bonds combines
Figure 5. Packing around the anion with the hydrogen bonding (dotted
lines) and the ring graph sets in the crystal structure of compound
6·2H2O. For two of the cations, only the amino groups (N8H2) are shown
for simplicity.
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Energetic Hydrazine-Based Salts with Nitrogen-Rich and Oxidizing Anions
Figure 9. Disorder in the anion in the crystal structure of BaACHTNUGTRNEG(UN NH4)(NT)3.
the anion identical, and the disorder in the anion is charac-
terized by two possible orientations twisted by 1808.
The unit cell of BaACHTUNRGTNEUNG(NH4)(NT)3 (Figure 10) is made up of
Figure 7. Labeling scheme and ring graph sets (the hydrogen bonds are
represented by dotted lines) in the crystal structure of compound 7.
8ꢅ1/8=one Ba2+ cation (occupying the vertices), 12ꢅ1/4=
three disordered 5-nitrotetrazole anions (occupying the mid-
points of the sides), and one ammonium cation (occupying
the center).
with the classical hydrogen bond (C3···O20i =3.517(3) and
N1···O12iii =2.838(3) ꢃ) to form the R4,4(20) networks.
Figure 8 shows a view of the unit cell of compound 7. The
picrate anions form wavy layers, which are linked to each
other by hydrogen bonding to the cations. In a layer, two
methyl groups of the cation form hydrogen bonds with the
same oxygen atom of one of the nitro groups (C4···O21i =
3.391(3) and C5···O21i =3.484(3) ꢃ), leading to the forma-
tion of R1,2(6) motifs.
As illustrated in Figure 11, the barium cations coordinate
to the 5-nitrotetrazole anions, which act as bidentate ligands.
The coordination number around the cations is twelve and
completed by interactions to six symmetrically equivalent
anions with Ba···N5=2.916(7) and Ba···O3=3.056(7) ꢃ.
Figure 10. View along the c-axis of the unit cell of BaACHTNUGTRNEG(UN NH4)(NT)3 with
the disordered 5-nitrotetrazole anions (ellipsoid model) and the barium
cations (ball-and-stick model). The hydrogen atoms around the ammoni-
um cation could not be found.
Figure 8. Unit cell of compound 7 (view along the a-axis) with the ring
graph sets (the hydrogen bonds are represented by dotted lines).
As mentioned above, single crystals of Ba
(NT=5-nitrotetrazole anion) were obtained during the syn-
thesis of compound 9. Ba(NH4)(NT)3 is a mixed salt com-
ACHTUGNERTN(NUNG NH4)(NT)3
AHCTUNGTRENNUNG
posed of three 5-nitrotetrazole anions, one barium cation,
and one ammonium cation so that the overall charge is zero.
Unfortunately, the quality of the crystals did not allow us to
localize the hydrogen atoms of the ammonium cation. The
compound crystallizes in a cubic cell, and the 5-nitrotetra-
zole anions are disordered so that two possible orientations
are possible with the same probability. Figure 9 shows the
disorder of the anion in the structure of the compound. A
Figure 11. Coordination around the Ba2+ cations (dotted lines) in the
crystal structure of BaACHTNUGTRNEG(UN NH4)(NT)3 (view along the a-axis). Only one of
À
symmetry plane along the C N bond makes both halves of
the two possible orientations of the 5-nitrotetrazole anions is shown.
Chem. Asian J. 2012, 00, 0 – 0
ꢂ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.chemasianj.org
5
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Carles Mirꢄ Sabatꢀ et al.
FULL PAPER
+
À
Table 3. Physical, chemical and thermodynamic properties of salts of the [(CH3)3N NH2] cation.
This results in the formation
of infinite (coordination)
chains along all three axes,
with the ammonium cations
occupying the voids be-
tween anions.
2
3
4
5
7
8
9
10
Formula
C3H11N3O3 C3H11N2ClO4 C3H11N5 C4H13N7 C9H13N5O7 C3H11N5O4 C4H11N7O2 C4H11N5O6
Mol. Mass [g
137.14
174.58
117.15
159.19
303.23
181.15
189.18
225.16
molÀ1
]
Tm [8C][a]
Td [8C][b]
–
258
66
–
322
53
À64
1.589
759
182
216
60
À157
1.217*
759
-
238
264
60
À92
1.573
759
–
155
74
–
175
69
À97
1.479
759
–
137
74
À53
1.603
759
250
62
À145
1.439
759
N+O [%][c]
W [%][d]
À99
À66
1.497
759
Physical, Chemical, and
Energetic Properties
[e]
1 [gcmÀ3
]
1.437
DfH8 (g, Cat+)/ 759
kJmolÀ1[f]
The sensitivities of com-
pounds 2–5 and 7–10 to-
wards fast heating without
confinement where evaluat-
ed by burning the materials
DfH8 (g, AnÀ)/ À312
À276
192
175
À370
À122
104
À217
kJmolÀ1[f]
DUL/kJmolÀ1[g] 537
DHL/kJmolÀ1[g] 542
517
522
À39
536
539
169
516
521
247
447
452
À243
505
510
À73
497
502
212
485
490
À96
DfH8 (s)/
kJmolÀ1[h]
DfU8 (s)/
kJkgÀ1[h]
À96
with
a
Bunsen burner
À547
À101
1615
1706
À698
À266
1254
À464
(“flame test”). Additionally,
we assessed the thermal sta-
bilities of all compounds by
means of differential scan-
ning calorimetry (DSC)
measurements. We then cal-
culated the standard enthal-
pies (H) and standard free
energies (G) of all com-
pounds in this work using
the modified complete basis
set (CBS-4M) method (Sup-
[a] Melting point (DSC onset, measurement at b=58C minÀ1); [b] decomposition point (DSC onset, measurement
at b=58C minÀ1); [c] combined nitrogen and oxygen contents; [d] oxygen balance; [e] density (from the crystal
structure or from the picnometer measurements), *density of compound 4 from ref. [18a]; [f] standard (gas phase)
heats of formation of the cation (Cat+) and of the anion (AnÀ); [g] (solid-phase) lattice energies and lattice en-
thalpies; [h] standard (solid-phase) formation heats/energies of the ionic species.
Table 4. Detonation parameters (calculated using the EXPLO5 code) and initial safety testing data for salts of the
+
À
[(CH3)3N NH2] cation.
Tex [K][a] Pdet [kbar][b] D [msÀ1
]
V0 [LkgÀ1
]
Isp [s][e] Impact [J][f] Friction [N][f] ESD
Thermal
[c]
[d]
(+/À)[g] Shock[h]
2
2799
218
246
132
181
190
7905
7912
6790
7468
7208
883
818
854
810
686
213
238
184
181
190
>50
<40
>50
>50
>50
>360
>360
>360
>360
>360
À
À
À
À
À
burns
burns fast
burns
burns
burns
3[i] 3612
porting
Information,
4
5
7
1866
1850
3027
Table S4). These values were
then used to estimate the
formation energies and en-
thalpies of compounds 2–5
and 7–10. Subsequently, we
used the calculated forma-
tion energies and the
EXPLO5 software[30] to esti-
mate the detonation param-
eters of salts 2–5 and 7–10.
Additionally, we simulated
formulations of compounds
2–5 and 7–10 with oxidizers,
slowly
8
9
3139
2686
228
201
260
7947
7595
8176
870
798
820
219
202
235
<12
<2
<10
<30
<48
<20
À
À
À
deflagrates
deflagrates
deflagrates
10 3550
[a] Temperatures of the explosion gases; [b] calculated detonation pressures; [c] calculated detonation velocities;
[d] volumes of the explosion gases; [e] specific impulses (calculated for an isobaric combustion at a chamber pres-
sure of 60.0 bar); [f] impact and friction sensitivities (according to BAM methods); [g] rough sensitivities to elec-
trostatic discharge (+ and À indicate sensitive and insensitive, respectively); [h] responses to fast heating in the
flame of a Bunsen burner (“flame test”); [i] the detonation parameters (excepting Isp) of compound 3 were calcu-
lated for a mixture containing 99% of 3+1% trifluorotrinitroazahexane (TFNA).
namely ammonium nitrate (AN) and ammonium dinitra-
mide (ADN), and also predicted the detonation parameters
of the mixtures. The results of these measurements and cal-
culations are summarized in Tables 3 and 4 and in the Sup-
porting Information (Tables S5 and S6).
The “flame tests” resulted in slow burning for the less en-
ergetic picrate salt 7, normal burning for the more energetic
compounds 2, 4, and 5 and fast burning/deflagration for the
better oxygen-balanced salts 3, 8, 9, and 10. On the other
hand, the DSC measurements showed a defined melting for
compounds 4 and 7 at 182 and 2388C, respectively, whereas
the remainder of the salts melted with concomitant decom-
position. Salts 8 and 10 have low thermal stabilities and de-
compose sharply at 155 and 1378C, respectively. The rest of
the salts have good to excellent thermal stabilities with the
perchlorate salt 3 exhibiting the highest decomposition point
at 3228C. The formation energies of the salts of the
+
À
[(CH3)3N NH2] cation vary between À698 (7) and 1706
(5) kJkgÀ1 and are approximately between that of the com-
monly used diaminotrinitrobenzene (DATB), DfU8=
À403 kJkgÀ1,[31] and that of the recently reported 1-proparg-
yl-1,1-dimethylhydrazinium
dicyanamide
(DfU8=
1734 kJkgÀ1).[9] Regardless of being a highly exothermic
compound (DfU8=1615 kJkgÀ1), the low crystal density of
the azide salt 4 (1=1.217 gcmÀ3) accounts for its low deto-
nation pressure and detonation velocity (Pdet =132 kbar and
D=6790 msÀ1). On the other hand, the higher density of
the nitroformiate salt 10 (1=1.603 gcmÀ3) explains the
higher detonation parameters of the latter material (Pdet
=
260 kbar and D=8176 msÀ1). For the remainder of the com-
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ꢂ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Chem. Asian J. 0000, 00, 0 – 0
ÝÝ These are not the final page numbers!

Energetic Hydrazine-Based Salts with Nitrogen-Rich and Oxidizing Anions
pounds the detonation pressures are in the range 181 to
246 kbar and the detonation velocities vary between 7208
and 7947 msÀ1. By comparison, 2,4,6-trinitrotoluene (TNT)
has a detonation pressure of 195 kbar and a detonation ve-
largest amount of nitrogen gas (ca. 350 gkgÀ1). After water
and nitrogen, the main decomposition product is expected
to be carbon soot. The amounts are expected to be lower,
the less negative the oxygen balance of the materials, so that
the better oxygen-balanced perchlorate and dinitramide
salts (compounds 3 and 8) are expected to form less carbon
soot (ca. 185 gkgÀ1). The amounts of ammonia gas predicted
are higher for the salts with the non-oxidizing azide and 5-
amino-1H-tetrazole salts (compounds 4 and 5, ca. 300 gkgÀ1)
than for the remainder of the compounds containing an
oxygen-based anion. The amounts of gases such as CO2, CO,
locity of 6881 msÀ1.[31] The specific impulses of the salts of
+
À
the [(CH3)3N NH2] cation in this work are in the range be-
tween 181 (5) and 238 seconds (3) and are comparable to
those of recently reported hydrazine-based salts.[9] Formula-
tions of the compounds in this work with AN and ADN at
neutral oxygen ratios have improved the predicted perform-
ances in comparison to the stand-alone materials (Support-
ing Information, Tables S5 and S6). Mixtures with AN have
detonation pressures in the range 262 (4+AN) to 278 kbar
(3+AN and 10+AN), detonation velocities between 8147
(4+AN) and 8322 msÀ1 (10+AN), and specific impulses,
which vary between 227 (4+AN and 5+AN) and 236 sec-
onds (3+AN). The ADN formulations have higher predict-
ed performances than the AN mixtures (Pdet =334–343 kbar,
D=8777–8953 msÀ1, and Isp =248–255 s).
H2, CH4, or HCN are generally low. Formulations of the
+
À
salts of the [(CH3)3N NH2] cation with AN and ADN at
approximately neutral oxygen ratios are predicted to form
three main decomposition products (Supporting Informa-
tion, Tables S7 and S8). For the formulations with AN, gas-
eous water is expected to be the major product (between
437 and 494 gkgÀ1), followed by nitrogen gas (between 304
and 381 gkgÀ1) and carbon dioxide (between 124 and
231 gkgÀ1). On the other hand, the ADN mixtures are ex-
pected to decompose forming mainly nitrogen gas (between
366 and 476 gkgÀ1), followed by water vapor (between 310
and 378 gkgÀ1) and carbon dioxide (between 158 and
283 gkgÀ1). The predicted heats of explosion of the pure
compounds vary between very low for the nitrogen-richer
salts 4 and 5 (ca. 660 calgÀ1) to high for the better oxygen-
balanced materials 3 and 10 (ca. 1615 calgÀ1). Formulations
of the compounds with higher heats of explosion with AN
are expected to reduce their values in comparison to the
stand-alone materials, while salts 4 and 5, which have lower
heats of explosion, are expected to increase their values
when formulated with AN. The formulations with ADN
generally show a significant increase in the heats of explo-
sion, although the materials with higher heats of explosion
(e.g., 3: 1631 calgÀ1) are expected to have slightly lower
values when formulated with ADN (3+AND: 1605 calgÀ1).
Commonly used energetic compounds such as 1,3,5-trinitro-
perhydro-1,3,5-triazine (RDX) have values of about
1590 calgÀ1.[37]
We used standard BAM tests (BAM=Bundesanstalt fꢆr
Materialforschung und –prꢆfung; Federal Institute for Mate-
rials Research and Testing) to assess the sensitivities of all
compounds in this work to impact, friction, and electrostatic
discharge.[32–35] All tested materials are insensitive to an elec-
trostatic discharge of approximately 20 kV. Compounds 2–7
are insensitive to impact and friction, whereas the better
oxygen-balanced compounds 8–10 are either very sensitive
or sensitive to impact and very sensitive towards friction ac-
cording to the UN recommendations on the transport of
dangerous goods[35] By comparison, TNT has an impact sen-
sitivity of 15 J and a friction sensitivity of 355 N.[31]
Heats of Explosion and Decomposition Gases
We used the ICT software[36] to predict the heats of explo-
sion and the decomposition gases of the energetic salts of
+
À
the [(CH3)3N NH2]
(Table 5).
cation described in this report
In general, for the compounds with an oxygen-based
anion, gaseous water is the major predicted decomposition
product, followed by the formation of molecular nitrogen.
In particular, the nitrogen-richer azide and 5-amino-1H-tet-
razole salts (compounds 4 and 5) are predicted to form the
Conclusions
1,1,1-Trimethylhydrazinium
À
iodide ([(CH3)3N NH2]I, 1) was
used as a starting material for
+
À
Table 5. Predicted heats of explosion and decompositions gases of energetic salts of the [(CH3)3N NH2] cati-
on.[a]
the synthesis of energetic salts
+
[b]
À
of the [(CH3)3N NH2] cation
Compound
CO2
H2O
N2
CO
H2
NH3
CH4
HCN
C
DHex [calgÀ1
]
with nitrogen-rich (azide, 5-
amino-1H-tetrazolate, and 5-ni-
trotetrazolate) and oxidizing
(nitrate, perchlorate, picrate, di-
nitramide, and nitroformiate)
anions. The compounds were
fully characterized including X-
ray crystal structure determina-
tion. The hydrogen-bonding
2
5
16
–
387
394
–
189
119
353
351
215
320
395
292
5
8
–
–
24
7
3
5
2
8
6
2
2
3
1
142
49
297
321
18
80
148
22
31
10
135
78
6
9
30
2
1
235
191
206
243
317
184
228
179
1415
1631
670
3[c]
4
0.6
1.3
1.3
0.4
0.8
1
5
7
8
9
–
–
649
88
16
3
328
379
186
392
1265
1424
1097
1599
10
93
17
0.5
[a] The amount of gases formed at 298 K is given in grams of gas per kilogram of energetic compound;
[b] heat of explosion; [c] additionally, HCl (209 gkgÀ1) was predicted for the perchlorate salt 3.
Chem. Asian J. 2012, 00, 0 – 0
ꢂ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.chemasianj.org
7
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Carles Mirꢄ Sabatꢀ et al.
FULL PAPER
(27, [Cat10A11]À), 1569.6 (29, [Cat11A12]À), 1706.7 (33, [Cat12A13]À), 1843.7
(31, [Cat13A14]À), 1980.7 (28, [Cat14A15]À); elemental analysis (%) calcd
for C3H11N3O3 (MW=137.14 gmolÀ1): C 26.27, H 8.08, N 30.64; found C
26.56, H 8.27, N 30.87.
networks found in the solid state in the structures of salts 1,
6, and 7 were described in the formalism of graph-set analy-
sis. Additionally, we also determined the crystal structure of
BaACHTUNGTRENNUNG(NH4)(NT)3 (NT=5-nitrotetrazole anion). With the ex-
1,1,1-Trimethylhydrazinium perchlorate (3)
ception of the oxygen-richer dinitramide and nitroformiate
salts 8 and 10, the remainder of the materials have good to
excellent thermal stabilities up to 3228C. While com-
pounds 8–10 have relatively high sensitivities towards
impact and friction (BAM tests), the rest of the materials
are insensitive to the same stimuli. Except for the low-densi-
ty azide salt 4, the calculated detonation velocities of all
compounds in this work are higher than that of the com-
monly used TNT, and most of the salts in this work are less
sensitive towards classical stimuli than TNT. Lastly, the
amounts of toxic gases predicted upon decomposition of
salts 2–5 and 7–10 (using the ICT code) are relatively low
and are reduced in the case of oxygen-balanced formula-
tions with ammonium nitrate and ammonium dinitramide,
which in turn have higher (computed) performances.
The crude product was dissolved in methanol, the insolubles were fil-
tered, and the solvent was removed under reduced pressure to yield a col-
1
orless powder (0.659 g, 94%). DSC (58CminÀ1,8C): 322.1 (dec); H NMR
À
([D6]DMSO, 400.18 MHz, TMS): d=3.24 (9H, s, CH3), 6.04 ppm (2H,
s(br), NH2); 13C NMR ([D6]DMSO, 100.52 MHz, TMS): d=57.3 ppm
À
( CH3); 15N NMR ([D6]DMSO, 50.77 MHz, NH3) d/ppm: +128.8 (t, JN-
1
À
À
À
NACHTUNGTRENNUNG
H =67.7 Hz, NH2), +79.7 (s,
462(7) 479(4) 627(6) 747(19) 912(6) 935ACTHUNGTRENNUNG
3045 cmÀ1 (3); IR (golden gate, rel. int.): n˜ =3343(w) 3284(w) 3204(w)
3054(w) 2924(w) 1617(m) 1540(w) 1510(w) 1481(m) 1407(w) 1325(w)
1297(w) 1264(w) 1047(s) 945(s) 901(m) 820(w) 772(w) 746(w) 698(w)
678(w) 650(w) 620(s) 554(w) 544(w) 520(w) 506(w) 468(w) 460 cmÀ1 (w).
MS m/z (ESI+): 249.0 (53, [Cat2A]+), 423.1 (5, [Cat3A2]+), 597.2 (66,
[Cat4A3]+), 773.2 (100, [Cat5A4]+), 945.3 (23, [Cat6A5]+), 1119.4 (21,
[Cat7A6]+), 1297.1 (48, [Cat8A7]+), 1471.0 (37 [Cat9A8]+), 1644.9 (46,
[Cat10A9]+), 1818.9 (20, [Cat11A10]+); m/z (ESIÀ): 273.2 (10, [CatA2]À),
447.2 (1, [Cat2A3]À), 623.2 (28, [Cat3A4]À), 797.1 (40, [Cat4A5]À), 971.5
(42, [Cat5A6]À), 1145.6 (56, [Cat6A7]À), 1321.4 (33, [Cat7A8]À), 1495.3 (41,
[Cat8A9]À), 1671.3 (100, [Cat9A10]À), 1845.4 (43, [Cat10A11]À); elemental
analysis (%) calcd for C3H11N2ClO4 (MW=174.58 gmolÀ1): C 20.64, H
6.35, N 16.05; found C 20.47, H 6.18, N 15.79.
Experimental Section
Cautionary Note
1,1,1-Trimethylhydrazinium 5-amino-1H-tetrazolate (5)
Hydrazines and its derivatives are powerful fuels and might react vigo-
rously with certain oxidizers. Many of the compounds handled and de-
scribed in this work are sensitive and/or potentially explosive materials.
Special care needs to be taken, in particular, when working with silver
azide and handling compounds 8–10. Thus, we recommend the handling
of these materials to be carried out only by expert personnel and using
safety equipment (e.g., Kevlar/leather gloves, Kevlar/leather coat, face
shield, and ear plugs).
The crude product was treated in the same way as the nitrate salt 2
(0.567 g, 89%). DSC (58C minÀ1,8C): 250.1 (dec); 1H NMR ([D6]DMSO,
À
À
400.18 MHz, TMS): d=3.28 (9H, s, CH3), 3.99 (2H, s(br), C NH2),
6.39 ppm (2H, s(br), N NH2); 13C NMR ([D6]DMSO, 100.52 MHz,
À
À
À
TMS): d=57.1 ( CH3), 164.2 ppm (C NH2); Raman (rel. int.): n˜ =407(1)
486(1) 499(2) 708(2) 749(17) 900(1) 911(3) 1046ACTHNUTRGNE(NUG 100) 1461(4) 2958(6)
3040 cmÀ1 (4); IR (golden gate, rel. int.): n˜ =3288(w) 3145(w) 3049(w)
3014(w) 1608(m) 1483(m) 1433(w) 1318(m) 1288(m) 1203(w) 1154(w)
1109(w) 1050(s) 942(vs) 895(s) 829(m) 811(w) 772(w) 745(m) 688(w)
670(w) 630(w) 591(w) 573(w) 526(w) 497(w) 476(w) 469 cmÀ1 (w). MS m/
General Method for the Preparation of Salts 2–6
z
(ESI+): 234.0 (100, [Cat2A]+), 393.2 (11, [Cat3A2]+), 552.5 (6,
The corresponding silver salt, i.e., silver nitrate (0.680 g, 4.0 mmol), silver
perchlorate (0.830 g, 4.0 mmol), silver 5-amino-1H-tetrazolate (0.921 g,
4.8 mmol), and silver sulfate (0.623 g, 2.0 mmol) was dissolved/suspended
in distilled water (10 mL), and neat compound 1 (0.808 g, 4.0 mmol) was
added portionwise. The reaction mixture was stirred at room temperature
under the exclusion of light for 4 h (compounds 2, 3, and 6) or overnight
(compound 5). The insoluble silver iodide was then removed by filtration
and the solvent was removed under reduced pressure and at 408C. The
crude product was treated as described below.
[Cat4A3]+), 711.7 (4, [Cat5A4]+); m/z (ESIÀ): 242.9 (6, [CatA2]À), 402.5
(3, [Cat2A3]À), 561.6 (46, [Cat3A4]À), 720.8 (80, [Cat4A5]À), 879.7 (91,
[Cat5A6]À), 1038.7 (100, [Cat6A7]À), 1198.0 (59, [Cat7A8]À), 1357.0 (56,
[Cat8A9]À); Raman (rel. int.): n˜ =407(1) 486(1) 499(2) 708(2) 749(17)
900(1) 911(3) 1046ACTHNUTRGNEUNG
(100) 1461(4) 2958(6) 3040 cmÀ1 (4); IR (golden gate,
rel. int.): n˜ =3288(w) 3145(w) 3049(w) 3014(w) 1608(m) 1483(m) 1433(w)
1318(m) 1288(m) 1203(w) 1154(w) 1109(w) 1050(s) 942(vs) 895(s) 829(m)
811(w) 772(w) 745(m) 688(w) 670(w) 630(w) 591(w) 573(w) 526(w)
497(w) 476(w) 469 cmÀ1 (w); elemental analysis (%) calcd for C4H13N7
(MW=159.19 gmolÀ1): C 30.18, H 8.23, N 61.59; found C 30.02, H 8.11,
N 61.17.
1,1,1-Trimethylhydrazinium nitrate (2)
The crude product was washed twice with THF (2ꢅ5.0 mL) and twice
with diethyl ether (2ꢅ5.0 mL) and dried under high vacuum to give a col-
orless crystalline solid (0.527 g, 96%). DSC (58C minÀ1,8C): 258.0 (dec);
General Method for the Preparation of the Barium Salt
1H NMR ([D6]DMSO, 400.18 MHz, TMS): d=3.26 (9H, s, CH3),
À
The barium salts of dinitramide, 5-nitrotetrazole, and nitroform were pre-
pared by the reaction of ammonium dinitramide, ammonium 5-nitrotetra-
zolate, and hydrazinium nitroformate, respectively, with half an equiva-
lent of barium hydroxide octahydrate and used “in situ” for the reactions
below.
6.11 ppm (2H, s(br), NH2); 13C NMR ([D6]DMSO, 100.52 MHz, TMS):
À
À
d=57.2 ppm ( CH3); Raman (rel. int.): n˜ =435(4) 461(7) 484(4) 749(89)
910(6) 947(8) 1043(62) 1052
G
2952(22) 3035 cmÀ1 (24); IR (golden gate, rel. int.): n˜ =3385(w) 3278(m)
3164(m) 3035(w) 1617(m) 1517(vs) 1483(m) 1467(w) 1442(m) 1346(m)
1216(w) 1205(w) 1160(m) 1134(m) 1109(m) 1091(s) 1001(w) 989(w)
947(m) 908(w) 833(w) 785(w) 751(w) 725(w) 710(w) 641(w) 544(w)
506(w) 497(w) 476(w) 468 cmÀ1 (w); MS m/z (ESI+): 212.0 (38, [Cat2A]+
), 349.1 (63, [Cat3A2]+), 486.2 (100, [Cat4A3]+), 623.3 (80, [Cat5A4]+),
760.3 (58, [Cat6A5]+), 897.3 (36, [Cat7A6]+), 1034.5 (52, [Cat8A7]+),
1171.5 (45 [Cat9A8]+), 1308.5 (46, [Cat10A9]+), 1445.5 (41, [Cat11A10]+),
1582.6 (31 [Cat12A11]+), 1720.0 (17, [Cat13A12]+), 1857.6 (19, [Cat14A13]+);
m/z (ESIÀ): 198.9 (2, [CatA2]À), 336.1 (1, [Cat2A3]À), 473.3 (7, [Cat3A4]À),
610.5 (13, [Cat4A5]À), 747.5 (22, [Cat5A6]À), 884.4 (61, [Cat6A7]À), 1021.6
(45, [Cat7A8]À), 1158.4 (64, [Cat8A9]À), 1295.4 (100, [Cat9A10]À), 1432.7
General Method for the Preparation of Salts 7–10
The corresponding barium salt, i.e., barium picrate tetrahydrate (1.331 g,
2.0 mmol), barium dinitramide (0.699 g, 2.0 mmol), barium 5-nitrotetrazo-
late (0.731 g, 2.0 mmol), and barium nitroformate (0.875 g, 2.0 mmol) was
dissolved/suspended in distilled water (10 mL) and neat compound
6·2H2O (0.565 g, 2.0 mmol) was added portionwise. The reaction mixture
was stirred at room temperature for 2 h and the insoluble barium sulfate
was filtered through a plug of Celite. The solvent was then removed
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Energetic Hydrazine-Based Salts with Nitrogen-Rich and Oxidizing Anions
under reduced pressure and at 408C, yielding the crude product, which
1,1,1-Trimethylhydrazinium nitroformate (10)
was treated as described below.
The crude product was treated in the same way as the dinitramide salt 8
(0.801 g, 89%). DSC (58C minÀ1,8C): 106.9 (dec); 1H NMR ([D6]DMSO,
1,1,1-Trimethylhydrazinium picrate (7)
À
À
400.18 MHz, TMS): d=3.25 (9H, s, CH3), 6.09 ppm (2H, s(br), NH2);
13
The crude product was recrystallized from hot water yielding single crys-
tals of the compound suitable for the X-ray experiments (1.067 g, 88%).
DSC (58C minÀ1,8C): 238.0 (mp), 263.6 (dec); 1H NMR ([D6]DMSO,
À
C NMR ([D6]DMSO, 100.52 MHz, TMS): d=57.2 ( CH3), 150.7 ppm
À
(C NO2); Raman (rel. int.): n˜ =251(3) 463(2) 495(3) 748(5) 788(7) 868-
(100) 1148(11) 1271(14) 1378(15) 1464(3) 2973(2) 3047 cmÀ1 (1); IR
À
À
400.18 MHz, TMS): d=3.25 (9H, s, CH3), 6.09 (2H, s(br), N NH2),
(golden gate, rel. int.): n˜ =3318(w) 3198(w) 1623(w) 1534(m) 1477(s)
1402(m) 1372(m) 1249(s) 1142(s) 1072(m) 946(w) 909(w) 866(w) 786(s)
731(s) 565(w) 544(w) 521(w) 497(w) 484(w) 468 cmÀ1 (w); MS m/z (ESI+
): 299.9 (56, [Cat2A]+), 525.1 (31, [Cat3A2]+), 750.1 (26, [Cat4A3]+); m/z
(ESIÀ): 150.1 (16, [A]À), 375.0 (4, [CatA2]À), 600.1 (2, [Cat2A3]À), 825.3
(7, [Cat3A4]À), 1050.5 (4, [Cat4A5]À), 1275.0 (3, [Cat5A6]À), 1500.2 (5,
[Cat6A7]À); elemental analysis (%) calcd for C4H11N5O6 (MW=
225.16 gmolÀ1): C 21.34, H 4.92, N 31.10; found 21.11, H 4.70, N 30.79.
8.59 ppm (2H, s, Ar-H); 13C NMR ([D6]DMSO, 100.52 MHz, TMS): d=
À
160.7 (C1), 141.8 (C2), 125.2 (C3), 124.1 (C4), 57.2 ppm ( CH3); Raman
(rel. int.): n˜ =214(3) 330(11) 520(4) 707(9) 745(3) 821(90) 924(4) 942(31)
1074(2) 1165(7) 1257(24) 1309(75) 1329(73) 1347ACTHNUTRGNE(NUG 100) 1365(57) 1430(2)
1496(4) 1556(11) 2975(1) 3048 cmÀ1 (1); IR (golden gate, rel. int.): n˜ =
3326(w) 3156(w) 3078(w) 1631(m) 1609(s) 1567(s) 1547(s) 1516(s)
1481(s) 1426(m) 1362(s) 1325(vs) 1264(vs) 1163(s) 1109(m) 1072(s)
942(m) 911(s) 835(w) 820(w) 787(m) 743(s) 702(vs) 593(w) 554(w)
514(w) 497(w) 490(w) 468 cmÀ1 (w). MS m/z (ESI+): 377.9 (3, [Cat2A]+),
1286.8 (5, [Cat5A4]+); m/z (ESIÀ): 228.1 (100, [A]À), 479.0 (6, [2AÀ+Na+
]À), 530.9 (19, [CatA2]À), 708.0 (21, [3AÀ+Na++H+]À), 729.7 (7,
[3AÀ+2Na+]À); elemental analysis (%) calcd for C9H13N5O7 (MW=
303.23 gmolÀ1): C 35.65, H 4.32, N 23.09; found C 35.48, H 4.21, N 22.86.
Acknowledgements
1,1,1-Trimethylhydrazinium dinitramide (8)
Financial support by the CNRS (Centre Nationale de la Recherche Sci-
entifique) and the University Claude Bernard of Lyon are gratefully ac-
knowledged.
The crude product was treated twice with isopropanol (2·5 mL) and sub-
sequently evaporated to dryness (0.629 g, 87%). DSC (58C minÀ1,8C):
1
À
155.4 (dec); H NMR ([D6]DMSO, 400.18 MHz, TMS): d=3.25 (9H, s,
CH3), 6.07 ppm (2H, s(br), N NH2); 13C NMR ([D6]DMSO, 100.52 MHz,
À
[1] C. Nonnenberg, I. Frank, T. M. Klapçtke, Angew. Chem. 2004, 116,
4686–4689; Angew. Chem. Int. Ed. 2004, 43, 4586–4589.
[2] L. Catoire, N. Chaumeix, C. Paillard, J. Propul. Power 2004, 20, 87–
92.
[3] L. Catoire, N. Chaumeix, S. Pichon, C. Paillard, J. Propul. Power
2006, 22, 120–126.
À
TMS): d=57.3 ppm ( CH3); Raman (rel. int.): n˜ =298(11) 381(3) 483(12)
747(87) 827
A
3045 cmÀ1 (6); IR (golden gate, rel. int.): n˜ =3316(w) 3196(w) 3048(w)
1624(w) 1518(m) 1481(m) 1425(m) 1333(w) 1170(s) 1087(w) 1009(s)
945(m) 910(w) 826(w) 758(m) 726(w) 688(w) 679(w) 602(w) 573(w)
553(w) 497(w) 484(w) 469 cmÀ1 (w). MS m/z (ESI+): 256.0 (98, [Cat2A]+
), 437.1 (47, [Cat3A2]+), 618.2 (100, [Cat4A3]+), 799.2 (56, [Cat5A4]+),
980.0 (51, [Cat6A5]+), 1161.2 (64, [Cat7A6]+), 1342.2 (84, [Cat8A7]+),
1523.2 (36 [Cat9A8]+); m/z (ESIÀ): 287.1 (13, [CatA2]À), 468.0 (3,
[Cat2A3]À), 649.5 (46, [Cat3A4]À), 830.7 (32, [Cat4A5]À), 1011.6 (53,
[Cat5A6]À), 1192.7 (90, [Cat6A7]À), 1373.7 (87, [Cat7A8]À), 1554.4 (100,
[Cat8A9]À), 1735.5 (77, [Cat9A10]À), 1916.4 (46, [Cat10A11]À); elemental
analysis (%) calcd for C3H11N5O4 (MW=181.15 gmolÀ1): C 19.89, H 6.12,
N 38.66; found C 19.73, H 5.87, N 38.42.
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hart, Propellants Explos. Pyrotech. 2008, 33, 209–212.
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20–22 June 2001, Noordwijk, The Netherlands: http://esamultime-
dia.esa.int/conferences/01a05/index.html.
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1,1,1-Trimethylhydrazinium 5-nitrotetrazolate (9)
The pale yellow liquid obtained after concentration in vacuum was treat-
ed as described above for compound 8 to yield a colorless powder
(0.692 g, 91%). In one reaction illustrating the synthesis of compound 9,
ammonium 5-nitrotetrazolate was reacted with an equivalent amount of
barium hydroxide octahydrate to form barium 5-nitrotetrazolate, which
was reacted in situ with an equivalent amount of compound 6·H2O. The
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chamber yielding single crystals of BaACTHNUTRGNEUNG(NH4)(NT)3, which were used for
the X-ray experiments. DSC (58C minÀ1,8C): 175.3 (dec); 1H NMR
À
([D6]DMSO, 400.18 MHz, TMS): d=3.26 (9H, s, CH3), 6.10 ppm (2H,
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13
À
À
s(br), N NH2); C NMR ([D6]DMSO, 100.52 MHz, TMS): d=168.7 (C
À
NO2), 57.3 ppm ( CH3); Raman (rel. int.): n˜ =548(3) 753(3) 845(9)
1024(51) 1060(47) 1167(3) 1320(6) 1423
(100) 1535(4) 2981(2) 3043 cmÀ1
(1); IR (golden gate, rel. int.): n˜ =3235(m) 3145(m) 3038(w) 2851(w)
1645(w) 1542(s) 1485(m) 1467(m) 1439(s) 1413(s) 1315(s) 1295(w)
1167(m) 1149(w) 1106(m) 1057(w) 1023(w) 949(m) 922(w) 834(vs)
749(w) 667(m) 553(vw) 512(w) 491(w) 471(w) 461 cmÀ1 (w); MS m/z
(ESI+): 263.9 (100, [Cat2A]+), 453.1 (42, [Cat3A2]+), 642.1 (62, [Cat4A3]+
), 831.2 (68, [Cat5A4]+), 1020.2 (64, [Cat6A5]+), 1209.3 (63, [Cat7A6]+),
1398.3 (98, [Cat8A7]+), 1587.3 (33 [Cat9A8]+), 1776.3 (19, [Cat10A9]+); m/
z (ESIÀ): 303.1 (14, [CatA2]À), 492.5 (7, [Cat2A3]À), 681.5 (71, [Cat3A4]À),
870.6 (66, [Cat4A5]À), 1059.7 (38, [Cat5A6]À), 1248.6 (100, [Cat6A7]À),
1437.7 (58, [Cat7A8]À), 1626.6 (61, [Cat8A9]À), 1815.5 (46, [Cat9A10]À); ele-
mental analysis (%) calcd for C4H11N7O2 (MW=189.17 gmolÀ1): C 25.40,
H 5.86, N 51.83; found C 25.18, H 6.01, N 51.57.
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Carles Mirꢄ Sabatꢀ et al.
FULL PAPER
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Received: May 16, 2012
Published online: && &&, 0000
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ꢂ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Chem. Asian J. 0000, 00, 0 – 0
ÝÝ These are not the final page numbers!

FULL PAPER
Bursting with energy: 1,1,1-Trimethyl-
hydrazinium iodide (see figure) was
used as a starting material for the syn-
thesis of energetic salts with nitrogen-
rich and oxidizing anions. Many of the
compounds have excellent thermal sta-
bilities, low sensitivities towards classi-
cal stimuli, and performance values
higher than the commonly used 1,3,5-
trinitrotoluene (TNT).
Energetic Salts
Carles Mirꢁ Sabatꢂ,* Henri Delalu,
Erwann Jeanneau
&&&& — &&&&
Energetic Hydrazine-Based Salts with
Nitrogen-Rich and Oxidizing Anions
Chem. Asian J. 2012, 00, 0 – 0
ꢂ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.chemasianj.org
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