[Diaquasesqui(nitrato-κO)hemi(perchlorato-κO)copper(II)]-μ-{bis[5-methyl-3-(pyridin-2-yl)-1H-pyrazol-4-yl] selenide}-[triaqua(perchlorato-κO)copper(II)] nitrate monohydrate

Abstract

In the binuclear title complex, [Cu2(ClO4)1.5(NO3)1.5(C18H16N6Se)(H2O)5]NO3·H2O, both CuII ions are hexa­coordinated by O and N atoms, thus forming axially elongated CuO4N2 octa­hedra. The equatorial plane of each octa­hedron is formed by one chelating pyrazole–pyridine fragment of the organic ligand and two water mol­ecules. The axial positions in one octa­hedron are occupied by a water mol­ecule and a monodentately coordinated perchlorate anion, while those in the other are occupied by a nitrate anion and a disordered perchlorate/nitrate anion with equal site occupancy. The pyrazole–pyridine units of the organic selenide are trans-oriented to each other with a C—Se—C angle of 96.01 (14)°. In the crystal, uncoordinated nitrate anions and the coordinating water mol­ecules are involved in O—H⋯O and N—H⋯O hydrogen bonds, forming a bridge between the pyrazole group and the coordinating water mol­ecules. Further O—H⋯O hydrogen bonds between the complex mol­ecules and a π–π stacking inter­action with a centroid–centroid distance of 3.834 (4) Å are also observed.

Synthesis, structure and in vitro biological properties of a new copper(II) complex with 4-{[3-(pyridin-2-yl)-1H-pyrazol-1-yl]methyl}benzoic acid

“…Within the equatorial plane, the Cu-pyridine distances [Cu1-N1 = 2.022 (2) Å and Cu1-N4 = 2.022 (2) Å ] are shorter than the Cu-pyrazole separation [Cu1-N2 = 2.155 (2) Å ]. The equatorial Cu-N and Cu-Cl bond lengths agree with similar previously reported bond lengths (Chakrabarty et al, 2004;Seredyuk et al, 2013;Zhuang et al, 2010;Davydenko et al, 2011). As a consequence of pyrazole coordination in the axial versus the equatorial position, the bite angles of the L ligand differ slightly [74.38 (9) versus 78.11 (8) ], but are consistently smaller than 90 , causing an appreciable angle variance (Robinson et al, 1971) All classical hydrogen-bond donors find an acceptor in a suitable geometry; detailed information has been compiled in Table 2.…”