Synthesis, characterization and crystal structure of Ni(II) coordination polymer with 1,3,5 benzenetricarboxylic acid and 2,2′-bipyridine ligands

A Ni(II) coordination polymer namely {[Ni2(btc)2(bpy)2(μ-H2O)2(H2O)2][Ni(bpy)(H2O)4]}.4H2O (1) (H3btc is 1,3,5-benzenetricarboxylic acid and bpy is 2,2′-bipyridine) with nickel acetate tetrahydrate, was prepared under hydrothermal conditions and characterized by single crystal X-ray diffraction, FTIR, TGA and elemental analysis techniques. In compound (1), the asymmetric part of the unit cell was found to contain two independent halves of centrosymmetric, binuclear water-bridged complex [Ni2(μ-H2O)2(H2O)2(btc)2(bpy)2]2 −, an equivalent of the [Ni(bpy)(H2O)4]2 + complex and four uncoordinated water molecules. Single crystal X-ray analysis revealed that the complex crystallizes in the triclinic P-1 space group, with a = 9.0787(3) Å, b = 10.5726(4) Å, c = 30.0065(11) Å, α = 83.439(3)°, β = 88.213(3)° and γ = 65.361(4)°. A 3D coordination polymer network as a supramolecular structure is formed by means of numerous hydrogen bonds involving all hydrogen atoms from water molecules and carboxylate groups of btc ligands.