Structural diversity and photoluminescence properties of zinc coordination polymers constructed from 1,4-bis[2-(4-pyridyl)ethenyl]-2,3,5,6-tetramethylbenzene and para-dicarboxylates†
Abstract
Five new coordination networks, formulated as [Zn(1,4-BDC)(1,4-bpetmb)]n (1), [Zn2(1,4-CDC)2(1,4-bpetmb)2]n (2), {[Zn(4,4′-BPDC)(1,4-bpetmb)0.5]·0.25MeCN}n (3), [Zn(4,4′-OBBC)(1,4-bpetmb)0.5]n (4) and {[Zn(4,4′-CDBC)(1,4-bpetmb)]·0.5C6H12} (5), have been synthesized under solvothermal conditions, based on the dipyridyl linker 1,4-bis[2-(4-pyridyl)ethenyl]-2,3,5,6-tetramethylbenzene (1,4-bpetmb) along with 1,4-benzenedicarboxylic acid (1,4-H2BDC), 1,4-cyclohexanedicarboxylic acid (1,4-H2CDC), 4,4′-biphenyldicarboxylic acid (4,4′-H2BPDC), 4,4′-oxybisbenzoic acid (4,4′-H2OBBC) and 4,4′-carbonyldibenzoic acid (4,4′-H2CDBC), respectively. Compounds 1–5 have been structurally characterized by elemental analysis, IR spectroscopy, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction analysis. 1 represents a sixfold interpenetrating 66 diamondoid framework. 2 reveals a 3D twofold interpenetrating pcu network with point symbol 41263. 3 comprises a 3D fourfold interpenetrating 6-connected architecture with 41263 u topology. 4 exhibits a 3D threefold interpenetrating 6-connected framework with an unprecedented Schläfli symbol 55610. 5 displays a highly undulating 2D (4,4) net. A systematic structural comparison of these coordination polymers shows that the frameworks can be tuned by various para-dicarboxylates coligands. The thermal stability and photoluminescence properties of 1–5 in the solid state have also been investigated.