The role of Chlorine Interactions in the construction of Nickel(Ii) and Cobalt(Ii) Supramolecular Metal-Organic Frameworks Based on Mixed Tetrachloroterephthalate and 2,2'-Bipyridine Ligands

Abstract

Reactions of the rigid ligand 2,3,5,6-tetrachloro-1,4-benzenedicarboxylic acid (H 2 BDC-Cl 4 ) with nickel(II) and cobalt(II) metal salts in the presence of 2,2′-bipyridine in DMF/MeOH afforded [M(BDC-Cl 4 )(2,2′-bpy)(MeOH) 2 ] n (M = Ni or Co). The Ni complex has a one-dimensional (1-D) linear structure that is further extended into a three-dimensional (3-D) supramolecular framework by inter-chain C-H···Cl hydrogen bonds, whereas the Co compound shows a 1-D zigzag structure, which is further assembled into a 3-D supramolecular architecture through intermolecular C-H···Cl and Cl···Cl interactions. These results reveal that weak chlorine interactions play an important role in governing these supramolecular structures. Thermal and fluorescence properties have also been investigated.