Inorganic Chemistry, Vol.55, No.10, 4951-4957, 2016
Cyclopentaneteracarboxylic Metal-Organic Frameworks: Tuning the Distance between Layers and Pore Structures with N-Ligands
Five new isomorphic coordination polymers of the Co(II) ion, namely) {[Co2L(bpy)(0.5)(H2O)(2)]center dot 2H(2)O}(n) (1), {[Co2L(pbyb)(0.5)(H2O)(2)]center dot 3H(2)O}(n) (2), {[Co2L-(dPe)(0.5)(H2O)(2)]center dot 2H(2)O}(n) (3), {[Co2L(dpa)(0.5)(H2O)(2)]center dot 2.5H(2)O} (4), and {[Co2L(dip)(0.5)(H2O)(2)]center dot 3.5H(2)O}(n) (5) (H4L = cis,cis,cis,cis-1,2,3,4-cyclopentaneteracarboxylic acid, bpy = 4,4'-bipyridine, pbyb = 1,4-di(pyridine-411)benzene, dpe = 1,2-di(pyridine-4-71)ethane, dpa = (E)-1,2-di(pyridin-4-yl)diazene, and dip = 1,4-di(1H-imidazol-1-yl)benzene), have been synthesized under hydrothermal conditions. The L4- ligand maintains its original conformation of SSRR in all of these compounds, but {Co5L}(n) clusters shOw mirror coordination symmetry in 1, 2, and 4 while the clusters in 3 and 5 do not. The addition of different N-ligands can tune the distance between {Co2L}(n) layers and change the pore structures of the frameworks. Magnetic susceptibility measurements indicate that 1-5 exhibit antiferromagnetic behavior.