Synthesis, characterization, and crystal structure of 1,4-bis(3-aminopropyl)piperazineperchloratocopper(II) perchlorate

The complex [Cu(C10H24N4)(ClO4)]ClO4, where C10H24N4=1,4-bis(3-aminopropyl)piperazine was synthesized and characterized, and its molecular structure was established by X-ray diffraction. The complex crystallizes in orthorhombic Pbca (no. 61) with Z=8, a=14.417(3) Å, b=15.067(3) Å, and c=16.101(3) Å. The structure consists of isolated [Cu(C10H24N4)(ClO4)]+ cations and perchlorate counter anions. The coordination geometry of the Cu(II) center may be described as square pyramidal (SP) with ClO4− group at the apical site and the N donor atoms of the neutral tetradentate ligand occupy the basal sites. The Cu–N bond distances are 2.069(4), 2.020(3) Å for the internal chelate rings, and 2.033(4) and 1.996(3) Å for the outer rings. The Cu–O(1) distance is 2.454(3) Å. The central six-membered ring of the tetradentate ligand has a boat conformation, whereas the two terminal six-membered chelate rings of the amine ligand adopt the chair conformation.