Polyiodine-Modified 1,3,5-Benzenetricarboxylic Acid Framework Zn(II)/Cd(II) Complexes as Highly Selective Fluorescence Sensors for Thiamine Hydrochloride, NACs, and Fe3+/Zn2+

Four new complexes, [Zn(TIBTC)(DMA)]·[NH₂(CH₃)₂] (1), [Cd(TIBTC)(H₂O)]·[NH₂(CH₃)₂]·DMA (2), [Cd₂(TIBTC)(2,2'-bipy)₂(HCOO)] (3), and [Cd₂(DIBTC)(2,2'-bipy)₂(HCOO)] (4) (H₃TIBTC = 2,4,6-triiodo-1,3,5-benzenetricarboxylic acid, H₃DIBTC = 2,4-diiodo-1,3,5-benzenetricarboxylic acid, 2,2'-bipy = 2,2'-bipyridine, and DMA = dimethylacetamide), were successfully synthesized and characterized by elemental analysis, powder X-ray diffraction, infrared spectroscopy, ultraviolet-visible spectroscopy, and thermogravimetric analysis. Complexes 1 and 2 are three-dimensional supramolecular network structures, while complex 4 has a two-dimensional network structure. We preliminarily studied the fluorescence properties of the complexes and found that complexes 1-3 can detect thiamine hydrochloride, NACs, and Fe³⁺/Zn²⁺ with high sensitivity and selectivity.