Two 1D chain complexes based on N,N′-bis(4-pyridylmethyl)pyromellitic diimide and fluorescence azide sensing

Two complexes, {[Hg(4-pmpmd)Br₂]•CHCl₃)}<i>_n</i>(<b>1</b>), [Cd(4-pmpmd) (CF₃SO₃)₂]<i>_n</i> (<b>2</b>) were synthesized (4-pmpmd: N,N′-bis(4-pyridylmethyl)pyromellitic diimide). Both complexes were characterized by IR spectroscopy, powder X-ray diffraction, elemental analyses, single crystal X-ray diffraction, and thermogravimetric analyses. Complex <b>1</b> features a typical 1D zigzag chain structure with the adjacent chains intertwined via hydrogen bonds, while complex <b>2</b> shows 1D parallel-packed wavy chains structure through π···π stacking interactions. The weak interactions of pyromellitic diimide and anions effect on 1D chain supramolecular structural diversity. Taking advantage of azide anion strong binding affinities, complex <b>2</b> could be developed as fluorescence sensor for azide anion. Two 1D chain complexes were synthesized based on N,N′-bis(4-pyridylmethyl) pyromellitic diimide, the anions and pyromellitic diimide ligand effect on 1D chains supramolecular structural diversity. Complex <b>2</b> was promising for fluorescence sensing azide anion.