Crystal structures and properties of four coordination polymers constructed from flexible pamoic acid

Four novel coordination polymers constructed from flexible pamoic acid, namely [Co(pam)(4,4'-bipy)](n)center dot nH(2)O (1), [Ni(pam)(4,4'-bipy)(H2O)(2)](n)center dot 2nCH(3)CN (2), [Cd(pam)(py)(2)](n)center dot npy (3) and [Mn-2(pam)(2) (py)(6)(H2O)(2)](n)center dot 2nPy (4), (H(2)pam = pamoic acid, 4,4'-bipy = 4,4'-bipyridine, py = pyridine), have been synthesized and characterized by elemental analysis, infrared spectra and X-ray crystallography. Complex 1 is a 2-D coordination polymer constructed from chelating bis-bidentate pam and 4,4'-bipyridine bridging ligands. Complex 2 is a 2-D coordination polymer assembled by bis-monodentate pam and 4,4'-bipyridine, where acetonitrile is filled in the rectangle channels. Both 2-D coordination polymers display undulated (4,4) grid layers as sql topology. Complex 3 displays a 1-D polymeric chain using chelating bis-bidentate pam as bridging ligand. Complex 4 exhibits an interesting bis-monodentate pam-Mn(II) 1-D polymeric chain, in which exist two-type six-coordinated manganese centers. Mn(1) is bound to four pyridine ligands, whereas Mn(2) is combined to two pyridine and two H2O molecules. Their thermal stabilities have been investigated. Cadmium complex 3 displays strong green luminescence with emission maximum at 543 nm. (C) 2010 Elsevier Ltd. All rights reserved.