A Solid‐State‐Emissive 1, 8‐Naphthalimide Probe Based on Photoinduced Electron Transfer and Aggregation‐Induced Emission. Issue 14 (11th April 2019) - Georgiev, Nikolai I.
Abstract: In this work we focused on the design and synthesis of a fluorescence sensing 4‐chloro‐1, 8‐naptalimide derivative operating simultaneously by photoinduced electron transfer (PET) and aggregation induced emission (AIE) mechanisms. Absorption and fluorescence properties of the probe were studied as a function of pH in solution and in solid state as compared to the properties of similar 1, 8‐naphthalimide derivatives without a substituent at the 1, 8‐naphthalimide C‐4 position. The photoinduced fluorescence enhancement of the probe was FE = 22 after protonation in solution ( λ F = 405 nm, p K a = 8.50±0.08) and FE = 44 ( λ F = 472 nm) in solid state after reversible exposure on HCl and ammonia vapours due to the amalgamation of monomer emission and AIE. In solid state on paper support the PET process in the probe was switched " off " in a pH window 2.5‐1.5. Due to the remarkable changes in the fluorescence emission the synthesized compound was successfully applied as a solid‐state chemosensing material for rapid detection of acid‐base vapours and pH in aqueous solutions. The concept proposed herein could drive the classic AIE and PET molecular sensors towards new directions and practical applications. Abstract : A solid state emissive 4‐chloro‐1, 8‐naptalimide fluorophore based on simultaneous action of photoinduced electron transfer (PET) and aggregation induced emission (AIE) mechanisms was synthesised and studied. Due to the remarkable changes in the fluorescence emission the synthesised compound was successfully applied as a solid‐state chemosensing material (on glass plate and strip paper) for rapid detection of acid‐base vapours and pH in aqueous solutions.