Ligand geometry-driven formation of Zn(II) MOFs based on 1,3-bis[2-(4-pyridyl)ethenyl] benzene and aromatic dicarboxylic acids

Abstract

Abstract Based on the ligand 1,3-bis[2-(4-pyridyl)ethenyl] benzene (1,3-BPEB), three coordination polymers [Zn(1,3-BPEB)(1,4-BDC)]n (1), [Zn2(1,3-BPEB)(4,4′- BPDC)2·DMF]n (2), [Zn(1,3-BPEB)(4,4′-STDC)]n (3) have been obtained respectively by the hydrothermal synthesis of 1,4-benzenedicarboxylic acid (1,4-BDC), 4,4′-biphenyldicarboxylic acid (4,4′-BPDC) and 4,4′-stilbenedicarboxylic acid (4,4′-STDC) as auxiliary ligands. Single crystal X-ray diffraction showed that complex 1 possesses sql networks and the mutually parallel 2-D grids penetrate with each other constituting the 3-D structure which belongs to parallel interpenetration model of 2D → 3D. Complex 2 shows a kgd net and forms 2D → 3D parallel polycatenated architecture. Complex 3 has a fivefold interpenetrating 3D framework. The intentional change of the ligands’ geometries have a significant impact on the final frameworks of the complexes. Thermal stabilities and solid-state fluorescence properties of 1–3 have been investigated.