Cadmium(II) coordination polymers constructed from a bis-functionalized ligand 4′-(3-carboxypheny1)-2,2′:6′,2"-terpyridine: Synthesis, structure and luminescence

Five new cadmium(II) coordination polymers [Cd-2(L)(2)Cl-2](n).nH(2)O (1), [Cd(L)Cl(H2O)](n).n[Cd(HL)Cl-2].nH(2)O (2), [Cd-3(L)(1,4-bdc)(2.5)](n).4nH(2)O (3), [Cd-2(L)(HL)(1,3,5-btc)](n).2nH(2)O (4), [Cd-2(L)(2)(SO4)(n).2nH(2)O (5) (HL = 4'-(3-carboxyphenyl)-2,2':6',2"-terpyridine, H-2(1,4-bdc) = benzene-1,4-dicarboxylic acid, H-3(1,3,5-btc) = benzene-1,3,5-tricarboxylic acid) have been synthesized under hydrothermal conditions and characterized by elemental analysis, IR, and single crystal X-ray diffraction. Compounds 1 and 2 present a 1D chain structure, and further linked by the pi-pi interaction to form a 2D layer. Compound 3 features a new (3,3,9)-connected 3D network built up by [Cd-3(COO)(4)] clusters with the point symbol of {3.4(2)}{3(2).4(6).5(9).6(15).7(3).8}{4(3)}.Compound 4 exhibits a 2D layer structure with binuclear eight-membered rings, which demonstrates a new 3-nodal (3,3,4)-connected topological network with the point symbol of {5(2).6(2).9(2)}{5(2).6}(4). Compound 5 displays an achiral 2D layer based on 1D left- and right-handed helical chains and contains dinuclear [Cd-2(SO4)] clusters, which shows a 4-connected sql network with the point symbol of (4(4).6(2)). Additionally, the thermal stabilities and luminescent properties of 1-5 were investigated. (C) 2016 Elsevier Ltd. All rights reserved.