Philip W. Leonard

Crystal structure of 2-diazo-imidazole-4,5-dicarbo-nitrile.

In the title compound, C5N6, all the atoms are approximately coplanar. In the crystal, molecules are packed with short contact distances of 2.885 (2) (between the diazo N atom connected to the ring and a cyano N atom on a neighboring molecule) and 3.012 (2) Å (between the terminal diazo N atom and an N atom of a neighboring imidazole ring).

Simple and Efficient Synthesis of Explosive Cocrystals containing 3,5‐Dimethylpyrazol‐1‐yl‐substituted‐1,2,4,5‐tetrazines

The reaction of 3,4-dinitropyrazole, 5-nitrotetrazole, or 4-nitro-1,2,3-triazole with 1,2,4,5-tetrazines substituted with 3,5-dimethylpyrazolyl (dmp) groups results in energetic cocrystals after 1 minute of reflux and cooling to room temperature in yields of 89-92 %. Hydrogen-bonding between the dmp group to the N-H of the energetic heterocycles are the predominant interaction that stabilizes the new cocrystals. Each cocrystal packs in a different lattice structure and the cocrystals with sheet-like and herring-bone crystal packing orientations are less sensitive than the cocrystal with the interlocked structure. Electrostatic potential mapping helps rationalize why dmp-substituted tetrazines readily form cocrystals, whereas more electron-deficient pyrazolyl tetrazines do not. The calculated energetic performance of the new cocrystals approaches that of 2,4,6-trinitrotoluene (TNT) and importantly, these materials will aid in the rational design of new cocrystalline energetic materials.

Crystal structure of 2-azido-1H-imidazole-4,5-di-carbonitrile.

In the title compound, C5HN7, the nitrile and azido substituents are close to being coplanar with the central ring. Molecules in the crystal are linked via an N—H⋯N hydrogen bond to a nitrile acceptor, forming a chain extending along the c-axis direction.

Energetic salt of trinitrophloroglucinol and melamine

We hope to harness the field of energetic co-crystals for development of insensitive, high-performing explosives. As demonstrated by other groups, co-crystals of energetic materials are diverse in their resultant properties versus the native materials. Herein, we discuss the synthesis, characterization, and testing of an energetic co-crystal of trinitrophloroglucinol (1,3,5-trihydroxy-2,4,6-trinitrobenzene) and melamine. Although melamine is not an energetic material, high nitrogen content and insensitivity can be of benefit in a co-crystal. Currently, trinitrophloroglucinol (TNPG) and melamine have been found to exist as a 1:1 ionic co-crystal. Characterization by NMR, IR, small-scale sensitivity, thermal stability and powder X-ray diffraction have all been used to characterize the individual compounds as well as the co-crystals developed.

Final report for SERDP WP-2209 Replacement melt-castable formulations for Composition B

Abstract : Objective. Composition B is a melt-cas Objective. Composition B is a melt-castable explosive formulation incorporating TNT and RDX. Both of these components have undesirable environmental impacts from production and use. The desired outcome of this work was the selection of an explosive material to replace Comp-B that would preserve the beneficial attributes of that explosive without the negative environmental ramifications table explosive formulation incorporating TNT and RDX. Both of these components have undesirable environmental impacts from production and use. The desired outcome of this work was the selection of an explosive material to replace Comp-B that would preserve the beneficial attributes of that explosive without the negative environmental ramifications.

Crystal structures of the three closely related compounds: Bis[(1H-Tetrazol-5-yl)methyl]-nitramide, triaminoguanidinium 5-({[(1H-Tetrazol-5-yl)methyl](nitro)amino}methyl)tetrazol-1-ide, and diammonium bis[(tetrazol-1-id-5-yl)methyl]-nitramide monohydrate

The crystal packing and intermolecular hydrogen-bonding schemes vary greatly between the three compounds. In all three structures, the nitramide is mainly sp 2-hybridized and the bond lengths indicate delocalization of charges on the tetrazole rings.

Crystal structure of 4,5-di-nitro-1H-imidazole.

The title compound, C3H2N4O4, forms crystals with two molecules in the asymmetric unit which are conformationally similar. With the exception of the O atoms of the nitro groups, the molecules are essentially planar. In the crystal, adjacent molecules are associated by N—H⋯N hydrogen bonds involving the imidazole N—H donors and N-atom acceptors of the unsaturated nitrogen of neighboring rings, forming layers parallel to (010).