1D, 2D and 3D coordination polymers of 5,5′-methylenebis(oxy)dinicotinic acid with Co(II), Mn(II), Cu(II) and Cd(II) ions

A series of new coordination polymers of the 5,5'-methylenebis(oxy)dinicotinic acid ligand with various metal ions, have been synthesized under hydro(solvo)thermal conditions and characterized by X-ray crystallography: [Co(L)(H2O)(4)](n) (1), [Cu(L)(H2O)(2)](n) (2), two polymorphs of [Cd(L)(H2O)](n)center dot(DMA)(n) (3 and 4), [Co-4(L)(4)(H2O)(3)](n)center dot(acetonitrile)(n) (5), [Mn-2(L)(2)(H2O)](n)center dot(acetonitrile)(n) (6) and [Cd-2(L)(2)(H2O)](n)center dot(DMA)center dot 11/2(H2O)(n) (7) (H2L = 5,5'-methylenebis(oxy)dinicotinic acid; DMA = dimethyl acetamide) The hybrid metal-organic polymeric assemblies reveal diverse connectivity and topological features in one-, two- and three-dimensions, depending on the number of ligation sites available on the metal centers for binding the organic ligands and the nuclearity of connecting nodes. Compounds 1-4 involve mono-nuclear metal connectors and represent 1D and 2D coordination polymers. The three-dimensional single-framework polymers in compounds 5-7 are tessellated via dinuclear coordination nodes. Solid-state variable temperature magnetic susceptibility data of 5 and 6 involving the paramagnetic Co(II) and Mn(II) ions are reported as well. They reveal week anti-ferromagnetic coupling between the proxime metal centers observed in these two complexes.