Synthesis of a new class of carbon-bonded anionic sigma complexes with 1,3-dimethyl-2,6-dioxo-5-(2,4,6-trinitrophenyl)-1,2,3,6-tetrahydropyrimidin-4-olate moiety as insensitive high energy density materials -- implications from impact sensitivity and thermal testings.

Background: Poly nitro aromatic compounds are high energy density materials. Carbon-bonded anionic sigma complexes derived from them have remarkable thermal stability. At present there is a strong requirement for thermally stable insensitive high energy density materials (IHEDMs) in the energetic field which necessitates the present investigation.

Triethyl-ammonium 1,3-dimethyl-5-(2,4,6-trinitro-phenyl)barbiturate.

In the title mol-ecular salt [systematic name: triethyl-ammonium 1,3-dimethyl-2,6-dioxo-5-(2,4,6-trinitro-phen-yl)-1,2,3,6-tetra-hydro-pyrimidin-4-olate], C(6)H(16)N(+)·C(12)H(8)N(5)O(9) (-), the dihedral angle between the aromatic rings in the anion is 46.88 (8)°. The nitro group para to the ring junction is almost coplanar with its attached ring [dihedral angle = 0.