Poly[(μ-3,5-dinitro-2-oxidobenzoato)(μ-3-hydroxypyridine)copper(II)]

Abstract

A new coordination polymer, [Cu(C7H2N2O7)(C5H5NO)]n, exhibits a double-chain structure, in which 3,5-dinitro-2-oxidobenzoate and 3-hydroxypyridine both act as bridging ligands, connecting adjacent copper(II) centers to form an infinite double-stranded chain. The asymmetric unit contains one CuII ion, one 3,5-dinitro-2-oxidobenzoate ligand and a 3-hydroxypyridine ligand. Coordination by one N atom and three O atoms from two different 3,5-dinitro-2-oxidobenzoate ligands and a 3-hydroxypyridine ligand creates a square-planar CuII center, which is augmented by a less tightly bonded fifth phenol O atom to form a square-pyramidal five-coordinate complex with an essentially planar base. The double-stranded chains are stabilized by intrachain π–π interactions [the centroid-to-centroid distance between adjacent aromatic rings is 3.719 (7) Å], and further linked through O—H...O hydrogen bonds, forming a three-dimensional supramolecular network.