Fluorescent Macrocycles with Customizable Backbone: Design, Synthesis, and Detection of Explosive Picric Acid

Synthesis of size and functional-group tunable dansyl-appended fluorescent macrocycles MC-n, MC-h, MC-p, MC-c, MC-mx, and MC-px using click reaction is reported. Macrocycles were extensively characterized by using various spectroscopic and theoretical techniques. Fluorescent macrocycles showed positive-solvatofluorism, high quantum yields, and strong interactions with nitroaromatic-explosives. Sensing in real water-sample, soil and vapor phase revealed that MC-p exhibits selective detection of picric acid containing three nitro-groups when compared to other nitroaromatics and structurally similar aromatics. Paper-strip based sensor was developed for real-time detection.