Synthesis, crystal structure and properties of cobalt(II) and nickel(II) coordination polymers supported by functionalized dicarboxylate ligands

Four new coordination polymers of cobalt(II) and nickel(II) with functionalized dicarboxylate ligands, namely, [CoIIL1(2,2′-bpy)(H2O)] (1), [NiIIL1(2,2′-bpy)(H2O)]·H2O (2), [CoII2(L2)2(2,2′-bpy)2(H2O)] (3) and [NiII2(L2)2(2,2′-bpy)2(H2O)] (4), where H2L1 = 2,5-dibenzoylterephthalic acid, H2L2 = 4,6-bis(4-methylbenzoyl)isophthalic acid and 2,2′-bpy = 2,2′-bipyridine, were synthesized and characterized by elemental analysis, IR spectra and thermogravimetric analysis. Complex 1 exhibits a zigzag chain with a C–H ⋯ π interaction between the phenyl ring proton and the phenyl ring of an adjacent chains to form a 2D supramolecular sheet. Complex 2 contains two helical chains which extend into 2D via a C–H ⋯ π interaction between the pyridine ring proton and the pyridine ring. Complexes 3 and 4 are isomorphous with helical chains that extend in the same direction and further link to one another by supramolecular forces into a 2D structure. Moreover, magnetic and luminescence properties have been investigated for 1 and 2, respectively.