Job/Unit: Z13019
/KAP1
Date: 04-03-13 16:46:15
Pages: 6
D. L. Naud, M. A. Hiskey, D. E. Chavez
ARTICLE
(600 mL). The heterogeneous mixture was allowed to stir for 1 h be-
fore it was transferred to a separatory funnel. Tert-butylmethyl ether
(100 mL) was added and shaken. The aqueous layer was removed and
the organic layer washed with two 50 mL portions of saturated brine.
The organic layer was collected and dried with magnesium sulfate,
filtered, and the solvent stripped by rotary evaporation. To the resulting
residue was added a solution composed of NaOH (8.8 g, 0.22 mol) and
400 mL water and stirred until the mixture became homogeneous. The
solution was transferred to a 2 L beaker. A mixture composed of
NaNO2 (30 g, 0.43 mol) and potassium ferricyanide (3.5 g, 0.01 mol)
ignition temperatures and melting points. In other words, a
CDN compound will vaporize and combust to release chlorine
at lower temperatures than a thermally stable chlorine-contain-
ing polymer such as PVC. This may partly explain why in our
preliminary burn experiments the CDN donors were found to
be quite effective when incorporated with nitrocellulose, which
is easily ignitable and cooler burning. And the utility nitrocel-
lulose as a pyrotechnic ingredient has other advantages, speci-
fically: (1) NC is inexpensive and commercially available; (2)
the addition of small amounts of nitroguanidine to a nitrocellu- and water (65 mL) was added with vigorous stirring. In one portion,
solid sodium persulfate (27 g, 0.11 mol) was added to the solution and
allowed to stir for 2 h. The resulting precipitate was collected by fil-
tration, washed copiously with water and air dried (17.1 g or 66%
yield), m.p. 54 °C. CHN: calcd. 29.95% C, 3.77% H, 11.64% N;
lose-based formulation enhances the color purity; (3) NC al-
ready is intrinsically oxygen rich, which reduces the need for
oxidants; and (4) NC burns cleanly with little or no residue,
appropriate for low-smoke pyrotechnic applications. So, for all
of these reasons combined, the CDN/NC/NQ matrix appears
to be the most promising as a perchlorate-free, low-smoke py-
rotechnic formulation.
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found 30.14% C, 3.95% H, 11.34% N. H NMR (300 MHz, CDCl3):
δ = 1.55 (s, 3 H), 3.58 (s, 2 H), 4.69 (d, J = 13.5 Hz, 2 H), 4.79 (d, J
= 13.5, 2 H). 13C NMR (300 MHz, CDCl3): δ = 18.51, 45.74, 62.28,
100.59, 111.14. By differential scanning calorimetry (DSC), the onset
of decomposition with some exothermicity is 235 °C.
Because of their solubility in organic solvents, the CDN
compounds might be best incorporated and processed with
raw, fibrous NC using a solvent system that would partially
dissolve or swell the nitrocellulose fibers. This method will
not fully dissolve and destroy the fibrous nature of the nitrocel-
lulose, and therefore retain its good ignitability and high burn
speed characteristics, but still allow for the matrix to be
pressed or extruded into strongly bound shapes. The CDN ma-
terials in this processing method could act as plasticizers, and
if necessary, additional co-plasticizers (such as 1,2,4-bu-
tanetriol trinitrate, BTTN, or trimethylolethane trinitrate,
TMETN) could also be added to improve the oxygen balance
and processing behavior. Because non-aqueous solvents are
employed, magnesium or magnesium-aluminum alloys could
be safely processed into the formulation. At the moment, the
simplest and most effective coloring agents are the oxidants
strontium and barium nitrates. To improve reactivity, the par-
ticle size of the nitrates should be as small as possible.
2-(Dichloromethyl)-2-methyl-5,5-dinitro-1,3-dioxane (11-CDN): In
a 100 mL flask, a mixture of BF3-etherate (37 mL, 0.29 mol), tris(hyd-
roxymethyl)-nitromethane (17.8 g, 0.118 mol), and 1b (12.5 g,
0.098 mol) was vigorously stirred for 12 h at room temperature. After-
wards, the reaction mixture was slowly poured into a 2 L beaker con-
taining sodium hydrogen carbonate (74 g) and water (750 mL). After
stirring for 1 h, tert-butyl methyl ether (200 mL) was added and the
mixture was transferred to a separatory funnel. The organic layer was
saved and washed twice with 100 mL portions of saturated brine, sub-
sequently, it was dried with magnesium sulfate, filtered, and its solvent
stripped by rotary evaporation. The resulting residue was treated with
an aqueous solution composed of NaOH (10 g) and water (360 mL).
Vigorous stirring and breaking up of the residue with a spatula was
required to facilitate its dissolution. After several hours of stirring, the
mixture was filtered to remove insoluble impurities. To the clear fil-
trate was added a mixture composed of sodium nitrite (27 g, 0.39 mol)
and potassium ferrocyanide (3.2 g, 0.01 mol) in water (60 mL). With
continued stirring solid sodium persulfate (24.5 g, 0.10 mol) was added
in one portion. After 4 h, the product was filtered throughto a Buchner
funnel and washed copiously with water and air dried (19.3 g, 70%
yield), m.p. 48 °C. CHN: calcd. 26.20% C, 2.93% H, 10.18% N;
Conclusions
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found 26.35% C, 3.06% H, 9.96% N. H NMR (300 MHz, CDCl3):
Three novel compounds based on the 1,3-dioxane system
were synthesized and investigated as possible chlorine donors
in perchlorate-free, low-smoke formulations. Simple pyrotech-
nic test mixtures utilizing these compounds along with a vari-
ety of fuels and nitrates were burned and their resulting flames
analyzed for color quality. The resulting color values (C.I.E.
1931) for some of the mixtures were equal or better than those
obtained by traditional means.
δ = 1.71 (s, 3 H), 4.71 (d, J = 13.6 Hz, 2 H), 4.89 (d, J = 13.6 Hz, 2
H), 5.71 (s, 1 H). 13C NMR (300 MHz, CDCl3): δ = 15.74, 63.32,
72.89, 102.65, 111.53. DSC analysis shows that the onset of decompo-
sition with some exothermicity is 239 °C.
2,2-Bis(chloromethyl)-5,5-dinitro-1,3-dioxane (13-CDN): Using the
identical procedure as described for 11-CDN, 13-CDN was obtained
from 1c in 44% yield; m.p. 78 °C. CHN: calcd. 26.20% C, 2.93% H,
10.18% N; found 26.52% C, 3.11% H, 9.76% N. 1H NMR
(300 MHz, CDCl3): δ = 3.78 (s, 4 H), 4.78 (s, 4 H). 13C NMR
(300 MHz, CDCl3): δ = 40.75, 62.55, 100.40, 111.22. The onset of
decomposition by DSC is 219 °C.
Experimental Section
2-Chloromethyl-2-methyl-5,5-dinitro-1,3-dioxane (1-CDN): Tris-
(hydroxymethyl)nitromethane (18.0 g, 0.119 mol)was added to aceto-
nitrile (100 mL) and stirred until the mixture became homogeneous.
Compound 1a (10.0 g, 0.108 mol) was added to the solution followed
by BF3-etherate complex (30 mL, 0.24 mol). Upon addition of the
Acknowledgements
This work was supported by the Laboratory Research And Develop-
complex, the temperature increased from 20 to 35 °C. After stirring ment office. Los Alamos National Laboratory is operated by Los Al-
for 90 min at room temperature, the solution was carefully poured into amos National Security (LANS, LLC) under contract No. DE-AC52–
2 L beaker containing sodium hydrogen carbonate (60 g) and water
06NA25396 for the U.S. Department of Energy.
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© 0000 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Z. Anorg. Allg. Chem. 0000, 0–0
Naud, Darren L.
