Synthesis, crystal structures, and theoretical calculations of two diverse three-dimensional hybrid materials based on polyoxoanions bridging macrocyclic copper/nickel complex

Abstract

Two hybrid materials, formulated as [NiL]3[VO3]6·2H2O (1) and [CuL][VO3]2·2H2O (2) (L = 1,8-dibutyl-1,3,6,8,10,13-hexaazacyclotetradecane), were obtained by the reactions of transition metal macrocyclic complexes [ML](ClO4)2 (M = Ni, Cu) with NH4VO3, characterized by elemental analysis, infrared spectroscopy analysis, thermogravimetric analysis, and X-ray powder diffraction. The single-crystal structures analysis showed that the Ni(II)/Cu(II) atom is coordinated by two oxygen atoms from [VO4] tetrahedra, plus four nitrogen atoms from L, forming a distorted six-coordinate octahedral coordination geometry. Six [VO4] tetrahedra form a hexanuclear [V6O18]6− ring by sharing six μ2 -oxygen atoms in compound 1, and the [VO4] tetrahedra are connected by sharing μ2 -oxygen atoms to form a one-dimensional zigzag chain of [VO3] n n - in compound 2. Compounds 1 and 2 show diverse three-dimensional structures, which are constructed by the connections of hexanuclear [V6O18]6- rings with [NiL]2+ moieties in compound 1, and [VO3] n n - chains with [CuL]2+ moieties in compound 2, respectively.