8 research outputs found
Refinement of Copper(II) Azide with 1‐Alkyl‐5H‐tetrazoles: Adaptable Energetic Complexes
A concept for stabilizing highly sensitive and explosive copper(II) azide with 1‐N‐substituted tetrazoles is described. It was possible to stabilize the system by the use of highly endothermic, nitrogen‐rich ligands. The sensitivities of the resulting energetic copper coordination compounds can be tuned further by variation of the alkyl chain of the ligands and by phlegmatization of the complexes with classical additives during the synthesis. It is demonstrated, using the compound based on 1‐methyl‐5H‐tetrazole ([Cu(N3)2(MTZ)], 1) that this class of complexes can be applied as a potential replacement for both lead azide (LA) and lead styphnate (LS). The complex was extensively investigated according to its chemical (elemental analysis, single‐crystal and powder X‐ray diffraction, IR spectroscopy, scanning electron microscopy) and physico‐chemical properties (differential thermal analysis, sensitivities towards impact, friction, and electrostatic discharge) compared to pure copper(II) azide
Copper(II) Chlorate Complexes: The Renaissance of a Forgotten and Misjudged Energetic Anion
A convenient synthetic
route toward new copper(II) chlorate complexes
with potential use in modern advanced ignition or initiation systems
is described. Obtained compounds were not only accurately characterized
(XRD, IR, UV/Vis EA and DTA) but also investigated for their energetic
character (sensitivities, initiation capability and laser ignition).
The copper 4-aminotriazolyl chlorate complex showed excellent initiation
of PETN, while also being thermally stable and safe to handle. Solid-state
UV–Vis measurements were performed to get a possible insight
toward the laser initiation mechanism. In contrast to expectations,
the presented copper(II) chlorate energetic coordination compounds
show manageable sensitivities that can be tamed or boosted by the
appropriate choice of nitrogen-rich ligands
Nitrogen-Rich Copper(II) Bromate Complexes: an Exotic Class of Primary Explosives
Because of the ongoing
very challenging search for potential replacements of the currently
used toxic lead-based primary explosives, new synthetic strategies
have to be developed. In particular, the smart concept of energetic
coordination compounds (ECC) has proven to hold great potential to
solve this difficult and complex problem. The herein-described approach
combines the exotic and neglected class of copper(II) bromate ECC
with different environmentally friendly nitrogen-rich heterocycles,
which exhibit the energetic properties of powerful primary explosives.
The concept is the simple adjustment of the energetic properties of
the complexes through alteration of the corresponding azoles. Six
new copper(II) bromate complexes with reasonable sensitivities are
featured in this study, which were synthesized in a practical and
straightforward fashion, assured through easy access to copper(II)
bromate obtained by metathesis reaction. Obtained compounds were comprehensively
characterized through various analytical methods such as low-temperature
X-ray diffraction, IR spectroscopy, and elemental analysis. Their
sensitivities toward impact and friction were assessed through BAM
standard techniques, together with their sensitivity against electrostatic
discharge. Evaluation of the energetic properties of the newly synthesized
compounds included examination of the respective thermal stabilities
by differential thermal analysis. Furthermore, the complexes were
tested regarding their behavior toward laser irradiation. Additionally,
to receive insight into a possible correlation between the laser-investigated
compounds’ optical absorption and their ability to ignite by
exposure to laser irradiation, UV–vis–near-IR spectra
were recorded
Copper(II) Chlorate Complexes: The Renaissance of a Forgotten and Misjudged Energetic Anion
A convenient synthetic
route toward new copper(II) chlorate complexes
with potential use in modern advanced ignition or initiation systems
is described. Obtained compounds were not only accurately characterized
(XRD, IR, UV/Vis EA and DTA) but also investigated for their energetic
character (sensitivities, initiation capability and laser ignition).
The copper 4-aminotriazolyl chlorate complex showed excellent initiation
of PETN, while also being thermally stable and safe to handle. Solid-state
UV–Vis measurements were performed to get a possible insight
toward the laser initiation mechanism. In contrast to expectations,
the presented copper(II) chlorate energetic coordination compounds
show manageable sensitivities that can be tamed or boosted by the
appropriate choice of nitrogen-rich ligands
Di(1<i>H</i>-tetrazol-5-yl)methane as Neutral Ligand in Energetic Transition Metal Complexes
The
synthesis of di(1<i>H</i>-tetrazol-5-yl)methane (<b>1</b>, 5-DTM), starting from commercially available sodium azide and malononitrile,
is described. This tetrazole was characterized and investigated for
use as a neutral nitrogen-rich ligand in various energetic transition
metal complexes: ([CuCl<sub>2</sub>(5-DTM)<sub>2</sub>]·2H<sub>2</sub>O (<b>2</b>), [Co(H<sub>2</sub>O)<sub>2</sub>(5-DTM)<sub>2</sub>]Cl<sub>2</sub> (<b>3</b>), [Ni(H<sub>2</sub>O)<sub>2</sub>(5-DTM)<sub>2</sub>]Cl<sub>2</sub> (<b>4</b>), [Co(H<sub>2</sub>O)<sub>2</sub>(5-DTM)<sub>2</sub>](NO<sub>3</sub>)<sub>2</sub> (<b>6</b>), [Ni(H<sub>2</sub>O)<sub>2</sub>(5-DTM)<sub>2</sub>](NO<sub>3</sub>)<sub>2</sub> (<b>7</b>), [Zn(H<sub>2</sub>O)<sub>2</sub>(5-DTM)<sub>2</sub>](NO<sub>3</sub>)<sub>2</sub> (<b>8</b>), {[Cu<sub>3</sub>(SO<sub>4</sub>)<sub>2</sub>(5-DTM<sub>–H</sub>)<sub>2</sub>(H<sub>2</sub>O)<sub>4</sub>(5-DTM)<sub>2</sub>]·2H<sub>2</sub>O}<sub>∞</sub> (<b>9</b>), [Cu(H<sub>2</sub>O)<sub>2</sub>(5-DTM)<sub>2</sub>](NO<sub>3</sub>)<sub>2</sub> (<b>11</b>), [Cu(NO<sub>3</sub>)<sub>2</sub>(5-DTM)<sub>2</sub>]·2H<sub>2</sub>O (<b>12</b>), [Cu(NO<sub>3</sub>)<sub>2</sub>(5-DTM)<sub>2</sub>] (<b>13</b>), [Cu(H<sub>2</sub>O)<sub>2</sub>(5-DTM)<sub>2</sub>](ClO<sub>4</sub>)<sub>2</sub> (<b>14</b>), and [Cu(ClO<sub>4</sub>)<sub>2</sub>(5-DTM)<sub>2</sub>] (<b>15</b>). Obtained coordination
compounds were characterized using single crystal X-ray diffraction
(except for <b>7</b> and <b>13</b>), IR spectroscopy,
elemental analysis, and differential thermal analysis. The sensitivities
to external stimuli (impact, friction, electrostatic discharge) were
determined. Complexes <b>12</b> and <b>13</b> were tested
for their ignitability by laser irradiation