1-(2-Hydroxyethyl)-3-nitro-1, 2, 4-triazole and its Complexes with Copper(II) Chloride and Copper(II) Perchlorate

1-(2-Hydroxyethyl)-3-nitro-1, 2, 4-triazole (hnt), prepared by alkylation of 3-nitro-1, 2, 4-triazole with 2-chloroethanol, was found to react with copper(II) chloride and copper(II) perchlorate in acetonitrile/ethanol solutions giving complexes [Cu2(hnt)2Cl4(H2O)2] and[Cu(hnt)2(H2O)3](ClO4)2, respectively. They are the first examples of coordination compounds with a neutral N-substituted 3-nitro-1, 2, 4-triazole ligand. 1-(2-Hydroxyethyl)-3-nitro-1, 2, 4-triazole and the obtained complexes were characterized by NMR and IR spectroscopy, X-ray, and thermal analyses. [Cu2(hnt)2Cl4(H2O)2] presents a dinuclear chlorido-bridged complex in which hnt acts as a chelating bidentate ligand, coordinated to the metal by a nitrogen atom of the triazole ring and an oxygen atom of the nitro group, and the copper atoms are inconsiderably distorted octahedral coordination. [Cu(hnt)2(H2O)3](ClO4)2comprises a mononuclear complex cation, in which two nitrogen atoms of two hnt ligands in trans configuration and three water oxygen atoms form a square pyramidal environment around the copper atom, which is completed to an distorted octahedron with a bifurcated vertex due to two additional elongated Cu–O bonds with two nitro groups. In both complexes, Cu–O bonds with the nitro groups may be considered as semi-coordinated.