Perylene tetra-(alkoxycarbonyl) derivative and its copper chelate for selective sensing of fluoride ions

Two novel fluoride ion fluorescent probes (P1 and P2) containing perylene tetra-(alkoxycarbonyl) derivative (PTAC) and its copper chelate were designed and synthesized. The identification properties of the probes were studied by absorption and fluorescence methods. The results showed that the probes were highly selective and sensitive to fluoride ions. ¹H NMR titration confirmed that the sensing mechanism involved the formation of H-bond between the O-H moiety and fluoride ions, and the coordination of copper ion could enhance the H-bond donor capacity of the receptor unit (O-H). The corresponding orbital electron distributions were calculated by density functional theory (DFT). In addition, fluoride ion can be easily detected by probe-coated Whatman filter paper without the need for expensive equipment. Until now, there have been few reports of such probes enhancing the capacity of the H-bond donor based on metal ion chelation. This study will contribute to the design and synthesis of novel sensitive perylene fluoride probes.