Herein, we describe the synthesis of coordination compounds starting from carbohydrazide ((H2NHN)2C=O (CHZ)) and the Zn2+ salt of dinitramic acid (HDN), which are high-nitrogen substances that exhibit properties similar to those of a burning-rate inhibitor of pyrotechnic compositions. This study demonstrates that these compounds react with glyoxal to furnish adducts of metal-organic macrocyclic cages bearing the elements of carbohydrazide, complexing metals and the HDN anion, depending on the ratio of the starting reactants. The assembled macrocyclic cage has "host-guest" properties and is a safe container for the storage of HDN salts. X-ray crystallographic analysis of the resultant coordination compound, [Zn(chz)3(N(NO2)2)2]), indicated that the metal-ligand association occurs via the N and O atoms of carbohydrazide. The zinc salt of dinitramic acid, which is enclosed into adducts with a macrocycle, is thermally stable and insensitive to mechanical impacts. The complex zinc salt of dinitramide was shown herein to exhibit inhibitory activity towards the burning rate of pyrotechnic compositions.
Keywords: adducts; carbohydrazide; dinitramide; glyoxal; macrocycles; zinc (II).