Metal- and anion-directed assemblies of CuII, CoII, NiII, and ZnII coordination polymers based on a bent dipyridyl ligand 4-amino-3,5-bis(3-pyridyl)-1,2,4-triazole and malonic acid

This work presents six CuII, CoII, NiII, and ZnII coordination polymers assembled from a bent dipyridyl ligand 4-amino-3,5-bis(3-pyridyl)-1,2,4-triazole (3-bpt) and malonic acid (H2mal), which have been prepared at ambient conditions in water–methanol solution. Single-crystal X-ray diffraction indicates that these complexes show a variety of 1-D (for 2–6) and 2-D (for 1) coordination patterns. The results evidently reveal the versatility of 3-bpt with different configurations and binding modes in coordination assemblies, which will be profoundly influenced by the metal ions and even inorganic counter anions. Furthermore, extended supramolecular architectures are constructed via multiple secondary interactions such as hydrogen bonding and aromatic stacking.

► Six new coordination polymers are assembled from a bent dipyridyl ligand and malonic acid.
► These coordination polymers display diverse 2-D and 1-D coordination networks regulated by metal ions and inorganic anions.
► Secondary interactions are critical to extend the coordination motifs into higher-dimensional supramolecular architectures.