Synthesis and characterization of fluorodinitroamine, FN(NO2)2

Article abstract of DOI:10.1002/anie.201410507

NF₃ and N(NO₂)₃ are known compounds, whereas the mixed fluoronitroamines, FN(NO₂)₂ and F₂NNO₂, have been unknown thus far. One of these, FN(NO₂)₂, has now been prepared and characterized by multinuclear NMR and Raman spectroscopy. FN(NO₂)₂ is the first known example of an inorganic fluoronitroamine. It is a thermally unstable, highly energetic material formed by the fluorination of the dinitramide anion using NF₄⁺ salts as the preferred fluorinating agent.

Full text of DOI:10.1002/anie.201410507

Angewandte
Chemie
DOI: 10.1002/anie.201410507
Energetic Materials
Synthesis and Characterization of Fluorodinitroamine, FN(NO ) **
2
2
Karl O. Christe,* William W. Wilson, Guillaume Bꢀlanger-Chabot, Ralf Haiges, Jerry A. Boatz,
Martin Rahm, G. K. Surya Prakash, Thomas Saal, and Mathias Hopfinger
In memory of Henry Zvi Selig
Abstract: NF and N(NO ) are known compounds, whereas
on the synthesis of fluorodinitroamine carried out during the
past 19 years in our laboratories at the Edwards Air Force
Base and the University of Southern California.
3
2 3
the mixed fluoronitroamines, FN(NO ) and F NNO , have
2
2
2
2
been unknown thus far. One of these, FN(NO ) , has now been
2
2
prepared and characterized by multinuclear NMR and Raman
spectroscopy. FN(NO2)2 is the first known example of an
inorganic fluoronitroamine. It is a thermally unstable, highly
energetic material formed by the fluorination of the dinitra-
In previous work, we have demonstrated the usefulness of
NF4 salts for the oxidative fluorination of anions. These
+
reactions involve the low-temperature metathesis of NF SbF
4
6
ꢀ
with a cesium or potassium salt of an OX anion, resulting in
the formation of an intermediate thermally unstable
+
mide anion using NF4 salts as the preferred fluorinating agent.
+
ꢀ
[
NF OX ] salt, followed by the thermal decomposition of
4
+
ꢀ
T
rifluoramine (NF ) is a very stable compound and has been
[NF OX ] to NF and the desired hypofluorite.
4 3
3
[5]
known for almost a century. It was first prepared in 1928 by
In this manner, high-yielding syntheses of FOClO ,
3
[
1]
[6]
[7]
[8]
[9]
Otto Ruff by the electrolysis of NH F/HF and is well
characterized. By contrast, trinitroamine (N(NO ) ) is
FONO2, FOSO F, FOTeF5, and FOIOF4 have been
4
2
[
2]
achieved. The preferred solvent for these reactions was
2
3
thermally unstable and decomposes above ꢀ408C. It has
not been isolated as a neat material, but instead has been
identified as a minor component in a complex reaction
anhydrous HF, and CsSbF was the by-product of choice
because of its low solubility in HF. If, however, the anion was
6
incompatible with HF, other solvents, such as SO , could also
2
1
4
mixture by N NMR spectroscopy and by several weak low-
be used. For SO , the use of potassium salts was preferred
2
[3]
temperature infrared absorptions (in CH CN).
because of the lower solubility of KSbF in this solvent. The
3
6
+
ꢀ
As the closely related CF(NO ) group is more stable than
intermediate formation of the NF OX salts was established
and NF SO F . As the
4 3
dinitramide anion (N(NO ) ) is well known,
2
2
4
+
ꢀ [5]
+
ꢀ
[7]
the C(NO2)3 group, it was interesting to synthesize and
characterize mixed fluoronitroamines (Scheme 1) and to
explore whether trinitroamine can also be stabilized by
partial fluorine substitution. Although alkylfluoronitroa-
by the isolation of NF ClO
4
4
ꢀ
[10–14]
it was
2
2
a potential starting material for the synthesis of the yet
unknown FN(NO ) molecule.
2
2
[
4]
mines (RNF(NO )) have been known for many years, the
Numerous experimental conditions for the synthesis of
FN(NO ) were investigated, including the use of KN(NO )
2
unsubstituted fluoronitroamines, F N(NO )
, where n = 1
n
2
(3ꢀn)
2
2
2 2
or 2, have not been known. Herein, we summarize our work
or CsN(NO ) as starting materials, of NF SbF , NF BF , F ,
2 2 4 6 4 4 2
or FOSO F as fluorinating agents, and of HF, SO , CH CN,
2
2
3
C H CN, CH NO , SO ClF, CH Cl , CHF , or C F H as
2
5
3
2
2
2
2
3
3
7
solvents. SO ClF, CH F, C F H, and CH Cl could not be used
2
3
3
7
2
2
because of the low solubilities of the starting materials in
these solvents at low temperature. With CH NO , explosions
Scheme 1. Simple fluoro- and nitro-substituted amines.
3
2
were encountered at ambient temperature. The preferred
combinations were KN(NO ) and NF SbF in either SO at
2
2
4
6
2
ꢀ
+
[6]
ꢀ
648C or CH CN at ꢀ308C. As with NF NO
,
3
4
3
+
ꢀ
[8]
+
ꢀ
[9]
+
ꢀ
2
NF TeF O , and NF IF O
,
the NF N(NO ) inter-
4 2
4
5
4
4
2
[
*] Prof. Dr. K. O. Christe, Dr. W. W. Wilson, G. Bꢀlanger-Chabot,
Prof. Dr. R. Haiges, Dr. J. A. Boatz, Dr. M. Rahm,
Prof. Dr. G. K. S. Prakash, T. Saal, M. Hopfinger
Loker Hydrocarbon Research Institute
University of Southern California
mediate could not be isolated because of its thermal
instability. The insoluble alkali metal SbF6 salts could be
ꢀ
filtered off at low temperature, weighed, and identified by
Raman spectroscopy. However, for the isolation of FN(NO ) ,
2
2
Los Angeles, CA 90089-1661 (USA)
E-mail: kchriste@usc.edu
the separation of the MSbF6 precipitate from the other
reaction products is not required. In SO or CH CN solutions,
2
3
[
**] This work was supported by the Office of Naval Research, the Air
Force Office of Scientific Research, the Defense Threat Reduction
Agency, and the National Science Foundation. Guillaume Belanger-
Chabot acknowledges support from the Fonds de recherche du
Quꢀbec-nature et technologies (FQRNT) and from the Natural
Sciences and Engineering Research Council of Canada (NSERC).
+
the dinitramide anion is directly fluorinated by the NF4
cation [Eq. (1), M = K].
þ
ꢀ
þ
ꢀ
2
NF4 SbF6 þ M NðNO Þ ! NF þ FNðNO Þ þ MSbF #
ð1Þ
2
3
2
2
6
The temperature dependence of the FN(NO ) formation
according to Eq. (1) was followed by F NMR spectroscopy
Supporting information for this article is available on the WWW
under http://dx.doi.org/10.1002/anie.201410507.
2 2
1
9
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1
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.
Angewandte
Communications
products were identified by their gas-phase infrared spectra.
The formation of SO F was also observed by a slow attack of
2
2
+
SO2 by NF . Furthermore, FNO can react with SO ,
4
2
2
+
ꢀ
resulting in the formation of solid NO SO F , which was
3
identified by its Raman spectrum. Its formation was verified
in a separate experiment [Eq. (4)].
þ
ꢀ
FNO þ SO ! NO SO F
ð4Þ
2
2
3
Although the in situ yield of FN(NO ) from the reaction
2
2
in SO solution, determined by NMR spectroscopy, is nearly
2
quantitative, the complete separation of FN(NO ) from the
2
2
SO solvent presents a major problem because of their similar
1
9
2
Figure 1. F NMR spectra of the KN(NO ) +NF SbF system in SO
2
2
2
4
6
volatilities and the thermal instability of FN(NO ) . To
2
2
solution recorded as a function of temperature.
circumvent this separation problem, the possibility of using
different solvents was investigated. As in the case of the
[
15]
recently discovered NCNO2, compatibility, solubility, vol-
atility and liquid-range problems render this a very difficult
(
Figure 1). As can be seen, the formation of FN(NO ) starts
2 2
task. For example, the use of CH CN suffers from its higher
already at ꢀ608C and proceeds well between ꢀ508C and
3
melting point of ꢀ418C and in some cases the formation of
ꢀ
208C. The increase in the intensity of the FN(NO ) signal is
2
2
+
CH COF. Thus, when a reaction of NF BF with KN(NO )
2 2
accompanied by the disappearance of the NF4 signal and the
intensity increase of the NF3 signal. Above ꢀ208C, the
concentration of FN(NO ) decreases as a result of decom-
3
4
4
was carried out in this solvent at ꢀ228C, the CH CN reacted
3
+
with the nitramide anion and NF , resulting in the formation
4
2
2
of acetyl fluoride, which was identified by its gas-phase IR
position.
[
16]
spectrum. When the reaction of KN(NO ) with NF SbF
6
In addition, two minor side reactions are also observed:
the fluorination of SO [Eq. (2)] and the formation of a small
amount of FONO [Eq. (3)] as a result of the presence of
a small amount of NO3 , a common impurity in dinitramide
2
2
4
was carried out in CH CN at ꢀ308C, no CH COF was
3
3
2
observed, however complete separation of FN(NO ) from
2 2
2
ꢀ
the solvent and N O by fractional condensation was not
2 4
achieved, as shown by low-temperature Raman spectroscopy.
Care must be taken to predissolve the separate reagents in
salts.
þ
ꢀ
NF4 SbF6 þ SO ! NF þ SO F þ SbF
ð2Þ
ð3Þ
CH CN when scaling up the reaction, otherwise deflagration
3
2
3
2
2
5
can occur. While the desired reaction also proceeds well in
propionitrile, complete separation of FN(NO2)2 from the
solvent by fractional condensation was not successful.
þ
ꢀ
þ
ꢀ
K NO3 þ NF4 SbF6 ! NF þ FONO þ KSbF
3
2
6
The formation of FN(NO ) in these solutions was also
confirmed by low-temperature Raman spectroscopy. After
the removal of most of the SO2 or CH CN solvents by
2
2
ꢀ
The fluorination of N(NO ) is not restricted to the use of
2
2
+
NF4 salts as the fluorinating agent. For example, F2 or
3
FOSO F were also used as fluorinating agents, but these
2
fractional condensation through ꢀ64, ꢀ78, and ꢀ908C traps,
modifications did not alleviate the separation problems.
Although the use of HF as a solvent suffers from its
competing reactions with the dinitramide anion, we suc-
ceeded on one occasion to isolate an essentially pure sample
of FN(NO ) for Raman spectroscopy from this system. When
the ꢀ78 and ꢀ908C traps contained the desired FN(NO )
2
2
and smaller amounts of solvent and N O . Complete removal
2
4
of the solvent and N O in this manner was not achieved.
2
4
In HF solution, the reactions are much more complicated
because of the fast reaction of the dinitramide anion with HF.
The results from a detailed study of this system are beyond
the scope of this paper and will be reported in a separate
publication.
For the synthesis of FN(NO ) , reactions of NF SbF with
either KN(NO ) in SO or CH CN solutions or CsN(NO ) in
HF solution were investigated [Eq. (1), M =K, Cs]. This
2
2
KN(NO ) was combined with NF SbF in anhydrous HF at
2
2
4
6
ꢀ788C, and all volatile products and the HF solvent were
pumped off at ꢀ648C, the resulting residue was allowed to
react further at ꢀ458C under a dynamic vacuum, and
FN(NO ) was trapped at ꢀ958C. Based on its low-temper-
2
2
4
6
2 2
ature Raman spectrum (Figure 2), the resulting product was
essentially pure FN(NO ) containing a small amount of N O
4
2
2
2
3
2 2
2
2
2
reaction could be best controlled in SO solution. The solvent
as the only detectable impurity. The exact nature of this
reaction is only poorly understood and was difficult to
duplicate.
2
was pumped off at ꢀ648C, and the volatile products,
generated by the decomposition of the unstable intermediate
+
ꢀ
NF N(NO ) between ꢀ608C and ꢀ568C, were pumped off
FN(NO ) is a colorless solid at low temperatures and
4
2
2
2 2
from the ꢀ788C trap. FN(NO ) is formed in SO solution in
melts at about ꢀ948C to a colorless liquid. Its composition
was established by multinuclear NMR and Raman spectros-
copy and quantum chemical calculations.
2
2
2
high yield (Figure 1). Several side reactions were also
observed in this system. First of all, FN(NO2)2 starts to
decompose at relatively low temperature, giving N O, NO /
1
9
The F NMR spectrum (Figure 1) shows a single, some-
what broadened resonance at 53 ppm, which is in good
agreement with those previously observed for the similar
2
2
N O , FNO , and some trans-N F , indicative of a decompo-
2
4
2
2 2
sition mechanism involving NO2 and NF radicals. These
2
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Chemie
Figure 2. Raman spectrum of solid FN(NO ) recorded at ꢀ1308C with
2
2
1
4
Figure 3. N NMR spectrum of FN(NO ) in SO solution recorded at
the 4880 ꢁ exciting line of an Ar ion laser at two different attenuations;
the bands marked by an asterisk are the result of a small amount of
N O .
2
2
2
ꢀ
438C; the weak signal at ꢀ19.7 ppm is the result of a trace of
[20b]
N O .
2
4
2
4
[
17]
compounds F NNF2 (60.4 ppm),
(
FN = C(CN)(CH )
of the decomposition product N O . Thus, the Raman
2 4
2
3
[
18]
14
60 ppm), and FN = C(CF3)2 (48.3 ppm).
The N NMR
spectrum clearly establishes the identity of this compound
as FN(NO ) .
spectrum (Figure 3) shows a broad resonance at ꢀ6.1 ppm for
2
2
the amidic nitrogen atom and a sharp doublet at ꢀ44.9 ppm
In the absence of a crystal structure, the good agreement
between the observed and calculated vibrational spectrum
lends strong support to the minimum energy structure
predicted by our calculations for free gaseous FN(NO2)2
(Figure 4). The structure is derived from a pseudo-tetrahe-
dron with the four ligand positions being occupied by two
nitro groups, one fluorine atom and a sterically active free
valence electron pair. The only symmetry element is a sym-
2
14
19
with a J( N- F) of 8 Hz for the nitro groups. The resonance
for the amidic nitrogen (ꢀ6.1 ppm) is similar to that of
[19]
ꢀ14.3 ppm found
for NF3 in accord with the similar
electronegativities of fluorine and the nitro group. The
signal for the nitro groups (ꢀ44.9 ppm) is similar to that
observed by us at ꢀ46.3 ppm for HN(NO ) in diethyl ether.
2
2
2
14
19
The J( N- F) coupling constant of 8 Hz for the nitro groups
is very similar to that of 9.8 Hz
[
20a]
1
14
found for FC(NO ) .
The J( N-
2
3
1
9
F) coupling could not be observed Table 1: Observed and calculated Raman spectra of FN(NO ) .
2
2
1
4
in the N NMR spectrum because
of the broadness of the amidic
nitrogen resonance. Attempts to
Vibrational assignments in C symmetry, Observed frequencies
Calculated frequencies
s
[a]
[a,b]
approximate mode description
[relative Raman intensities] [relative Raman intensities]
[
c]
1
A’ n nas NO ip
1 2
1743 [1] 1715 [16]
1351 [3], 1335 [2], 1332 [14] 1329 [100]
1064 [1], 1054 [0.5]
842 [2], 825 [31]
794 [22]
observe this J coupling constant in
n2 nsym NO ip
1
5
2
the N NMR spectrum of FN-
n3 n NF
1064 [8]
831 [63]
798 [14]
607 [15]
428 [86]
318 [24]
198 [16]
59 [9]
1
5
(
NO ) with natural N abundance
2 2
n4 dsciss NO ip
n5 nsym N3
rock NF
n7 dsciss N3
2
were also unsuccessful. Overall, the
1
9
14/15
F and
N NMR spectra are in
accord with the proposed FN(NO2)2
structure.
The Raman spectrum of solid
FN(NO ) is shown in Figure 2, and
n
6
d
615 [4], 606 [9]
430 sh, 425 [88]
329 [70]
207 [26], 200 [15]
77 [30]
n8 drock NO +d NF ip
2
rock
n9 dwag NO ip
n10 t NO ip
A’’ n11 nas NO oop
2
2
[c]
2
2
1682 sh, 1680 [4], 1668 [0.5] 1693 [44]
2
the observed frequencies and their
assignments are listed in Table 1.
The agreement between observed
and calculated vibrational spectra is
very good, particularly when keep-
ing in mind that the observed spec-
trum is for the solid, where solid-
state effects can influence some of
the frequencies and cause addi-
tional splittings of some of the
bands. The only observed impurities
n12 nsym NO oop
1254 [1], 1249 [3]
758 [3]
680 sh, 675 [5]
593 [9], 589 [9]
337 [10]
324 [100]
not observed
165 [20], 99 [20], 87 [8]
1244 [7]
743 [0]
692 [3]
604 [17]
328 [3]
306 [50]
(33) [5]
2
n13 dsciss NO oop
2
n
14
n
asym
N
3
n15 dwag NF
n16 drock NO +d NF oop
2
rock
n17 nsym NO oop
2
n18 t NO oop
2
lattice vibrations
ꢀ1
[
a] Frequencies in cm ; uncorrected intensities based on peak heights in percent based on the most
intense band being 100. [b] Calculated at the COSMO-mPW2PLYP/Def2-TZVPP level using individual
anharmonicity corrections for each mode obtained by comparing harmonic and anharmonic B3LYP/
aug-cc-pVTZ frequency calculations; Raman intensities were calculated at the B3LYP/aug-cc-pVTZ level
in the spectrum were small amounts of theory. [c] ip and oop stand for in-phase and out-of-phase, respectively.
Angew. Chem. Int. Ed. 2014, 53, 1 – 6
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3
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.
Angewandte
Communications
for NF and increases with an increasing number of the more
3
bulky nitro groups.
In conclusion, FN(NO ) , one of the two thus far unknown
2
2
mixed fluoronitroamines, has been prepared and character-
ized by multinuclear NMR and Raman spectroscopy. It is
a thermally unstable compound that readily decomposes to
N O , trans-N F , N O, and FNO . It is shown that in contrast
2
4
2
2
2
2
to the closely related trinitromethyl compounds, fluorine
substitution weakens the relatively labile NꢀN bonds in
N(NO ) , and that the yet unknown F N(NO ) molecule will
2
3
2
2
be even less stable than FN(NO ) , but might be accessible by
2
2
ꢀ
low-temperature fluorination of the known FN(NO2)
[
24]
anion.
Figure 4. Minimum energy structures of NF , F N(NO ), FN(NO ) ,
3
2
2
2
2
Experimental Section
and N(NO ) predicted at the M06-2X/aug-cc-pVTZ level (bond lengths
2
3
Caution! Anhydrous HF can cause severe burns and contact with the
skin must be avoided. Many of the materials described in this work
are energetic and should be handled on a small scale while taking
appropriate safety measures, such as wearing face shields, leather
gloves and protective clothing, and working in a well-ventilated
environment.
in ꢁ and bond angles in deg) viewed along the sterically active free
valence electron pair on the central nitrogen atom.
metry plane bisecting the fluorine ligand, the free valence
electron pair, and the central nitrogen atom. As can be seen
from the N-N-N and F-N-N bond angles of 103.78 and 104.78,
respectively, the sterically active lone pair is arguably more
voluminous than the remaining ligands, compressing their
bond angles from the ideal tetrahedral angle of 109.58 by
about 58. This view is supported by a quantum chemical
topological study of the lone pair domain by the HELP
All volatile materials were handled in either a stainless-steel/
[25]
Teflon-FEP
or Pyrex-glass vacuum line with greaseless Teflon
stopcocks. Solids were handled in the dry Ar atmosphere of a glove
[
26]
box. HF was dried by storage over BiF or TaF . Acetonitrile was
5
5
dried by storage over P
O10 and Linde 3 ꢀ molecular sieves and
4
distilled prior to use. A reported method was used for the preparation
[
27]
of NF SbF , and the sample of KN(NO ) was kindly donated by
4
6
2 2
EURENCO Bofors.
1
4
NMR spectra were recorded on a Bruker AMX 500 ( N, n =
[
21]
0
method (see the Supporting Information). Because of the
planarity of the N(NO ) group, the N-N-O bond angles are
36.13 MHz) and on a Varian-400 spectrometer. Spectra were exter-
2
nally referenced to neat CH NO (d = 0.00 ppm). Raman spectra
3 2 0
1
13.98. The predicted NꢀF bond length of 1.34 ꢀ is similar but
were recorded in 3 mm Pyrex tubes on a Cary Model 83 using the
4880 ꢀ excitation line of an Ar ion laser.
slightly shorter than that of 1.37 ꢀ experimentally found for
[
22]
Preparation of FN(NO ) : In a typical experiment, NF SbF
NF3,
and the NꢀO bond lengths are as expected for
2
2
4
6
(
2.00 mmol) and KN(NO ) (2.00 mmol) were loaded in the drybox
a normal NO group. The NꢀN bonds of 1.55 ꢀ are predicted
2 2
2
1
into a passivated = ’’ o.d. Teflon-FEP ampule closed by a stainless
4
to be considerably longer than those of 1.35–1.44 ꢀ typically
steel valve. The solvent (SO2 or CH CN, 2–5 mL) was added at
3
[23]
found in organic nitramines, in accord with the decreased
stability of FN(NO ) . Therefore, the predicted structure is in
ꢀ
1968C on the vacuum line and the mixture was warmed to the
2
2
melting point of the solvent at which point NF evolution began. The
3
agreement with the observed decomposition mode, that is, the
volatile products were separated by repeated fractional condensa-
tions through a series of ꢀ64, ꢀ80, ꢀ95, and ꢀ1968C traps in
a dynamic vacuum. The bulk of the desired FN(NO ) product was
found in the ꢀ78 and ꢀ958C traps. The purity of the isolated materials
was estimated by Raman and NMR measurements.
strong NꢀFand NꢀO bonds and weak NꢀN bonds result in an
easy loss of NO groups producing N O , and in the formation
2 2
2
2
4
of NF radicals producing trans-N F .
2
2
For a meaningful comparison of the trends within the NF3,
F N(NO ), FN(NO ) , and N(NO ) series, it was necessary to
Computational Details: Structure optimizations of NF , F N-
3
2
2
2
2
2
2
3
(NO ), FN(NO ) , and N(NO ) in the gas phase were calculated
2 2 2 2 3
calculate the structures of all the members at the same level of
using the hybrid meta exchange-correlation density functional M06-
[
28]
theory, as only the structure of NF is experimentally
2X, the aug-cc-pVTZ basis set, and Gaussian09, revA02. M06-
3
[
29]
[
22]
2X
is a reliable general-purpose density functional theory (DFT)
known. The results are shown in Figure 4. A comparison
functional for main-group chemistry, with a mean absolute deviation
of the observed structure of NF , rN-F = 1.37 ꢀ, ]F-N-F =
3
ꢀ
1
[30]
[22]
of 2.2 kcalmol , as demonstrated by several benchmarks.
The
1
1
02.18, with that predicted by us, rN-F = 1.36 ꢀ, ]F-N-F =
01.98, indicates that our predicted structures are good
[
31]
CBS-QB3 composite method was employed for calculating adia-
batic bond dissociation energies. CBS-QB3 is based on CCSD(T)
energies extrapolated to the basis set limit using MP2 and MP4
calculations together with empirical corrections, and is expected to be
highly reliable for thermochemistry.
in the G2 test set is reported to be 0.87 kcalmol
frequencies were calculated at the mPW2PLYP/Def2-TZVPP level
approximations to the actual structures. As can be seen
from Figure 4, substitution of a fluorine ligand in NF by
3
[
31,32]
a nitro group slightly shortens the NꢀF bonds. The NꢀN
Its mean absolute deviation
ꢀ
1 [33]
.
Harmonic
bonds in N(NO ) become increasingly longer and weaker
2
3
[
33]
with increasing fluorine substitution. Thus, the calculated Nꢀ
of theory using the ORCA 3.0 code, with implicit consideration of
N bond dissociation enthalpies for N(NO ) , FN(NO ) , and
2
ꢀ
3
2 2
CH CN solution, as treated by the COSMO method. Raman
3
1
F N(NO ) are 28.2, 22.1, and 14.2 kcalmol , respectively, and
2
2
intensities were calculated at the B3LYP/aug-cc-pVTZ level of
theory, using the standard implementation of the polarizable con-
F N(NO ) is predicted to be the least stable compound within
2
2
[
21]
this series. As expected, the tetrahedral angle is the smallest
tinuum model (PCM) of Gaussian09ꢁ. HELP analyses
were
4
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These are not the final page numbers!

Angewandte
Chemie
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Received: October 28, 2014
Published online: && &&, &&&&
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4
Keywords: dinitramide anion · energetic materials ·
.
fluoronitroamines · quantum chemical calculations
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Angew. Chem. Int. Ed. 2014, 53, 1 – 6
ꢀ 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
5
These are not the final page numbers!

.
Angewandte
Communications
Communications
Energetic Materials
A missing link: FN(NO ) , a fluoronitro-
2 2
amine, is a thermally unstable compound
that decomposes at about ꢀ208C. It is
shown that fluorine substitution further
weakens the NꢀN bonds in N(NO ) , and
K. O. Christe,* W. W. Wilson,
G. Bꢁlanger-Chabot, R. Haiges,
J. A. Boatz, M. Rahm, G. K. S. Prakash,
2
3
T. Saal, M. Hopfinger
&&&& — &&&&
the yet unknown F N(NO ) molecule is
2 2
thus predicted to be even less stable than
FN(NO ) .
Synthesis and Characterization of
Fluorodinitroamine, FN(NO2)2
2
2
6
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ꢀ 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2014, 53, 1 – 6
These are not the final page numbers!