Two coordination polymers assembled with resorcin[4]arenes ligand: Luminescent sensing Fe3+ion and Cr2O72-anion

Two coordination polymers, [Cd2L(btbp)0.5(DMF)(H2O)].3DMF (1) and [Zn2L(btbp)0.5(H2O)2].DMF.3H2O (2) have been synthesized base on resorcin[4]arene, btbp and metal ions in solvothermal conditions (H4L = 2,8,14,20-tetra-ethyl-4,10,16,22-tetrakis(4-carboxybenzyl)oxy)-6,12,18,24-tetra-methoxy-resorcin[4]arene, btbp = 4,4 '-bis(1,2,4-triazole-1-ylmethyl)biphenyl)). The structures of CPs 1 and 2 were determined by single -crystal X-ray diffractometer. Structural analysis shows that 1 and 2 exhibit layer structures. CPs 1 and 2 were characterized by Fourier transform infrared spectroscopy (FTIR), Powder X-ray diffraction (PXRD), elemental analysis and UV-vis Spectra. The solid-state emission spectra of 1 and 2 have been carried out and exhibit emission peaks at 452 nm (lambda ex = 364 nm) and 455 nm (lambda ex = 371 nm), respectively. Remarkably, CPs 1 and 2 exhibit excellent luminescent emissions in solid-state. Furthermore, CP 1 was used to detect Fe3+ and Cr2O72-in aqueous solution, and its sensitivity and anti-interference were also studied. The Stern-Volmer constant Ksv were 4.381 x 103 M-1and 1.1109 x 104 M-1, respectively. Further analysis showed that the quenching of CP 1 might be related to the energy competition of Fe3+ and Cr2O72-.