Vinylanthracene-Based Compounds as Electron-Rich Sensors for Explosives Recognition

Four new vinylanthracene-based fluorescent molecules were synthesized and characterized. The highly fluorescent vinylanthracene moiety was coupled with the ethynylbenzene group to yield rigid and electron-rich π systems, which were utilized as selective and sensitive probes for picric acid in both the solution and solid states. In solution, the molecules demonstrated signal amplification by a combined effect of photo-induced electron transfer and resonance energy transfer, whereas in the solid state the enhanced sensitivity was attributed to a collective effect of PET and exciton migration among closely spaced molecules. In direct contact mode experiments, thin films of the molecules demonstrated discernible changes in fluorescent intensity, which shows that the molecules are potential materials for in-the-field applications.