Influence of solvent on the structures of two copper(II) coordination polymers with tetraiodoterephthalate: syntheses, crystal structures, and properties

Abstract

Two Cu^II coordination polymers {[Cu(BDC-I₄)(MeOH)₄](H₂BDC-I₄)(MeOH)₂} _n (1) and [Cu(BDC-I₄)(dioxane)(MeOH)₂] _n (2) with a rigid periodinated ligand 2,3,5,6-tetraiodo-1,4-benzenedicarboxylic acid (H₂BDC-I₄) have been synthesized and characterized by elemental analysis, IR spectroscopy, and X-ray crystallography. Complex 1 presents a one-dimensional (1-D) linear structure, further assembled to form a two-dimensional (2-D) layer through inter-chain O–HI, O–HO, or C– weak interactions. Complex 2 shows a 1-D zigzag structure that is extended into a 2-D supramolecular network by intermolecular O–HO hydrogen bonds. The Cu^II in 1 has a distorted octahedral (CuO₆) coordination sphere, whereas Cu^II in 2 displays a nearly ideal square-pyramidal (CuO₅) coordination. The structural differences between 1 and 2 imply that solvent plays an important role in the construction of coordination architectures. In addition, the luminescent properties of H₂BDC-I₄, 1 and 2 in the solid state were investigated.

Keywords:

• Coordination polymer
• Solvent-controlled synthesis
• Cu^II tetraiodoterephthalate
• Crystal structure
• Luminescent property

Acknowledgements

We gratefully acknowledge the financial support from the National Natural Science Foundation of China (21201026) and A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), as well as Open Foundation of Jiangsu Province Key Laboratory of Fine Petrochemical Technology (KF1005).