Photoinduced Electron Transfer and Aggregation-Induced Emission in 1,8-Naphthalimide Probes as a Platform for Detection of Acid/Base Vapors

In the last few decades, photoinduced electron transfer (PET) based on "fluorophore-spacer-receptor" format became the most popular approach in the design of fluorescent sensing probes. As a result, a variety of architectures for detection of different chemical species has been synthesized, and PET has been well-studied in liquid solutions. The extension of the principles of molecular sensors from liquid solution onto solid support is currently a major task, which opens up new directions for practical applications. An approach for the design of solid state fluorescence-sensing materials could be based on aggregation-induced emission (AIE). That is why, herein, we focused our attention on the investigation of some 1,8-naphthalimides designed on classical "fluorophore-spacer-receptor" to serve as fluorescence-sensing materials in solid state via simultaneous PET and AIE. The effects of different substituents were investigated, and it was found that the examined compounds with well-pronounced AIE could be used as an efficient platform for rapid detection of pH and acid/base vapors in solid state.