Two new Zn(II) coordination polymers based on mixed pipemidic acid and flexible aromatic dicarboxylic acid ligands: Syntheses, crystal structures and luminescent properties

• Two new Zn(II) frameworks based on mixed pipemidic acid and flexible aromatic dicarboxylic acid ligands.
• Compound 1 features a 1D chain structure, and compound 2 features 6-connectedα-Po-type framework.
• These two compounds exhibit intense luminescence at room temperature.

Two new Zn(II) coordination polymers, namely [Zn(4,4′-sdb) (HPPA)]n (1) and [Zn(2,2′-bpdc)0.5(PPA)]n (2) (4,4′-H2sdb = 4,4′-sulfonyldibenzoate, 2,2′-H2bpdc = 2,2′-biphenyldicarboxylic acid, HPPA = pipemidic acid) were successfully obtained under hydrothermal conditions. These two compounds were further characterized by single-crystal X-ray diffraction analyses, elemental analyses, powder X-ray diffraction (PXRD) analyses and IR spectra. Compound 1 features a 1D chain structure, which further extended into a 3D supramolecular framework via intermolecular hydrogen bonds and weak van der Waals interactions, and compound 2 features a 3D framework with 6-connected α-Po-type topology. The structural regulation for these two compounds was successfully achieved by changing the flexible aromatic dicarboxylic acid ligand. Moreover, the thermal stabilities and luminescent properties for these two compounds were also investigated.

Via changing the flexible aromatic dicarboxylic acid ligand, namely [Zn(4,4′-sdb) (HPPA)]n (1) and [Zn(2,2′-bpdc)0.5(PPA)]n (2) (4,4′-H2sdb = 4,4′-sulfonyldibenzoate, 2,2′-H2bpdc = 2,2′-biphenyldicarboxylic acid, HPPA = pipemidic Acid). Compound 1 features a 1D chain structure, which further extended into a 3D supramolecular structure via intermolecular hydrogen bonding and weak van der Waals interactions, and compound 2 features a 3D framework with 6-connected α-Po-type topology.Figure optionsDownload as PowerPoint slide