Design and syntheses of two novel Mn(II) and Cu(II) complexes with 2,2′-biquinoline-4,4′-dicarboxylate and N-containing bidentate co-ligand

Hydrothermal reactions of Mn(II) or Cu(II) with the mixed ligands 2,2′-biquinoline-4,4′-dicarboxylic acid (H2bqdc), 4,4′-bispyridine (bipy) or dipyridin-2-ylamine (N3) lead to the isolation of two coordination polymers, namely, [Mn(bqdc)(bipy)]n (1) and {[Cu(bqdc)0.5(N3)2]·0.5bqdc·2H2O}n (2). Single-crystal X-ray analyses reveal that the complex 1 is the first three-dimensional non-interpenetrating 10-connected (312.430.52.6) topological framework with H2bqdc ligand, while the supramolecular structure of 2 exhibits a three-dimensional architecture via the π–π stacking interactions between the aromatic rings of N3 ligands and inter-chain hydrogen bonding. The H2bqdc ligand adopts bidentated and monodentated fashion in the 1 and 2, respectively. Moreover, compound 1 shows weak antimagnetic behavior.