A series of coordination polymers based on 5,5′-(ethane-1,2-diyl)-bis(oxy)diisophthalic acid and structurally related N-donor ligands: syntheses, structures and properties

Abstract

Ten new coordination polymers, namely, [Ni₂(L)(H₂O)₃]·5H₂O (1), [Ni₂(L)(pbib)₂(H₂O)]·H₂O (2), [Co₂(L)(pbib)_1.5]·2.5H₂O (3), [Co₂(L)(bbtz)_1.5(H₂O)₅] (4), [Ni(L)_0.5(biim-3)_0.5(H₂O)(CH₃CH₂OH)_0.5]·2H₂O (5), [Zn₃(L)(biim-3)(OH)₂] (6), [Ni(L)_0.5(btp)(H₂O)₂]·H₂O (7), [Zn₂(L)(btp)₂]·3H₂O (8), [Co(L)_0.5(btb)_0.5(H₂O)₂]·1.5H₂O (9), and [Zn(L)_0.5(btb)]·0.5H₂O (10), where pbib = 1,4-bis(imidazol-1-ylmethyl)benzene, bbtz = 1,4-bis(1H-1,2,4-triazol-1-ylmethyl)benzene, biim-3 = 1,3-bis(imidazol-1-yl)propane, btp = 1,3-bis(1,2,4-triazol-1-yl)propane, btb = 1,4-bis(1,2,4-triazol-1-yl)butane, and H₄L = 5,5′-(ethane-1,2-diyl)-bis(oxy)diisophthalic acid, have been synthesized under hydrothermal conditions. Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by infrared spectra (IR), elemental analyses, powder X-ray diffraction (PXRD) and thermogravimetric (TG) analyses. Compound 1 features a 2-fold interpenetrating diamond-like framework. Compound 2 is a 3D 4-connected net with the (8⁶)(7³·8²·9)(8²·9²·10²)(8²·9⁴) topology. Compound 3 is a 3D 2-fold interpenetrating framework with the (5·6²)(4·5⁴·6)(4²·5⁸·8⁵) topology. Compound 4 shows a rare 3D (4,7)-connected net with the (3·4·5·6³)(3²·4²·5·6¹³·7³) topology. Compounds 5 and 6 exhibit 3D 2-fold interpenetrating frameworks with the (5²·6²·8²)(4²·8²·9²)(4·5⁴·6) and (5⁴·6²) (5⁸·6⁶·7) topologies, respectively. Compounds 7 and 8 are 3D 3-fold interpenetrating frameworks with the 6⁴·8² and (6⁴·8²)₂(6⁶)₂ topologies, respectively. Compound 9 has a (3,4)-connected 2D layer structure with the (4·6²)(4²·6²·8²) topology. Compound 10 is a 3D 3-fold interpenetrating framework with the (6²·8)(6²·8²·10²) topology. The effects of the L anions, the N-donor ligands, and the metal ions on the structures of the coordination polymers have been discussed. The luminescent properties of 6, 8 and 10 and the optical band gaps of 1–10 have also been investigated in details.