Metal(II) coordination polymers derived from bis-pyridyl-bis-amide ligands and carboxylates: Syntheses, topological structures, and photoluminescence properties

摘要

Using bis-pyridyl-bis-amide ligands N,N'-bis-(4-pyridyl)phthalamide (L1), N,N'-bis-(4-pyridyl)iso-phthalamide (L2), hexanedioic acid bis-pyridin-4-ylamide (L3), and carboxylates, six metal(II) complexes formulated as Cd_2(1, 4-chdc)(L1)_2 · 4H_2O (1,4-H2chdc = 1,4-cyclohexanedicarboxylic acid) (1), Cd_2(L1)_2(in) _4 · 3DMF (Hin = isonicotinic acid) (2), Zn(L1)(1,4-bdc) (1,4-H_2bdc = 1,4-benzenedicarboxylic acid) (3), Cd(L_2)(1,4-chdc) (4), Zn_2(L_2)_2(tdc)_2 · DMF (H_2tdc = thiophene-2,5-dicarboxylic acid) (5), and Zn(2,6-ndc)_(0.5-) (L_3) _(0.5)(SO_4) · (CH_3NHCH_3) (2,6-H_2ndc = 2,6-naphthalenedicarboxylic acid) (6) have been hydro(solvo)thermally synthesized and structurally characterized by single-crystal X-ray diffraction. Complex 1 is a uninodal 6-connected noninterpenetrated three-dimensional (3D) network with {4~4.6 ~(10).8}-mab topology, complex 2 exhibits a uninodal 6-connected 2-fold interpenetrated 3D framework with {4~(12).6~3}-pcu topology, complex 3 shows a uninodal 8-fold interpenetrated 3D diamondoid framework, complexes 4 and 5 possess similar uninodal 2D layer with 4~4-sql topology, and complex 6 shows a framework of 2D → 3D inclined polycatenation based on 4~4-sql layer. The six complexes show different thermal stability and photoluminescence properties. The emission band of complex 1 becomes strong after dehydration, and water can reduce the emission intensities of the six complexes to some extents.