Structural Diversities and Fluorescent and Photocatalytic Properties of a Series of Cu-II Coordination Polymers Constructed from Flexible Bis-pyridyl-bis-amide Ligands with Different Spacer Lengths and Different Aromatic Carboxylates

Thirteen new Cull coordination polymers, namely, [Cu(3-dppa)(1,3,5-HBTC)] (1), [Cu(3-dpha)(1,3,5-HBTC)(H2O)]center dot H2O (2), [Cu-3(3-dpsea)(1,3,5-BTC)(2)-(H2O).5]center dot 4H(2)O (3), [Cu(3-dpba)(1,2-BDC)]center dot H2O (4), [Cu(3-dpha)(1,2-BDC)] (5), [Cu(3-dpsea)(1,2-BDC)]center dot H2O (6), [Cu-2(3-dpyp)(1,3-13DC)2(H2O)(4)]center dot 3H(2)O (7), [Cu(3-dppa)(1,3-BDC)(H2O)]center dot 2H(2)O (8), [Cu(3-dppia)(1,3-BDC)(H2O)(2)]center dot 2H(2)O (9), [Cu2(3-dpsea)2(1,3-BDC)2(H2O)(2)]center dot 7H(2)O (10), [Cu(3-dpba)(1,4-NDC)]center dot 3H(2)O (11), [Cu(3-dpyh)(1,4-NDC)(H2O)]center dot 3H(2)O (12), [Cu(3-dPYh)(0.5)(1,4-NDC)]center dot H2O (13), have been purposefully synthesized under hydrothermal conditions [3-dppa = N,N'-di(3-pyridyl)-propanediamide, 3-dpba = N,N'-di(3-pyridyl)butanediamide, 3-dpha = N,N'-di(3-pyridyl)hexanedioicdiamide, 3-dppia = N,N'-di(3-pyridyl)pimelicdiamide, 3-dpsea = N,N'-di(3-pyridyl)sebacicdiamide, 3-dpyp = N,N'-di(3-pyridinecarboxamide)-1,3-propane, 3-dpyh = N,N'-di(3-pyrkiinecarboxamide)-1,6-hexane, I,3,5-H3BTC = 1,3,5-benzenetricarboxylic acid, 1,2-H2BDC = 1,2-benzenedicarboxylic acid, 1,3-H2BDC = 1,3-benzenedicarboxylic acid and I,4-H2NDC = 1,4-naphthalenedicarboxylic acid]. Complexes 1-3 based on the same auxiliary ligand show various structures. Complex 1 features a one-dimensional (1D) infinity-like double-chain structure, which consists of a [Cu-1,3,5-HBTC](n) chain and [Cu-3-dppa](n) meso-helical chain. Complex 2 possesses a (2,4) undulated honeycomb (hcb) net. Complex 3 is a 3-fold interpenetrating three-dimensional (3D) framework, which shows trinodal (2,3,3)-connected topology with the Schlafli symbol of (10 center dot 12(2))2(103)2(12). Complexes 4-6 with I,2-BDC as secondary ligand exhibit different two-dimensional (2D) layer structures. Complex 4 exhibits a 2D (2,4)-connected (4 center dot 12(4)center dot 14)(4) net. Complexes 5 and 6 have similar structures and show 2D networks with undulated sql topology. For complexes 7-10 based on 1,3-BDC secondary ligand, complex 7 shows a ID zigzag chain, while complexes 8-10 have similar wave-like 2D structures. When I,4-NDC was used as the auxiliary ligand, complex 11 is a 2D puckered (4,4) network, complex 12 reveals a 4-connected topology with the point symbol of (4(4)center dot 6(2)), while complex 13 exhibits a 3-fold interpenetrating 3D alpha-Po framework. The structural diversity indicates that the bis-pyridyl-bis-amide ligands with different spacers and the aromatic polycarboxylates play important roles in tuning the dimensionalities and structures of the title complexes. The fluorescent and photocatalytic properties for 1-13 have also been investigated in detail.