Red-emissive quinoxaline-based BODIHY: Aggregation-induced emission and multi-responsive properties

• Published in: Dyes and pigments 2024-04, Vol.223, p.111974, Article 111974
• Main Authors: Dwivedi, Bhupendra Kumar, Bhowmik, Prasanta, Pandey, Sunil Kumar, Pandey, Daya Shankar
• Format: Article
• Language: English
• Subjects: Acidochromism; Aggregation induced emission; BODIHY; Mechanochromism; Solid state emission; Solvatochromism
• ISSN: 0143-7208; 1873-3743
• DOI: 10.1016/j.dyepig.2024.111974

Two new BODIHY-based AIEgens DQB1 and DQB2 including quinoxaline and benzothiazole scaffold have been synthesized and characterized. Comprehensive photophysical properties of the compounds in solution and aggregated/solid state have been investigated and fine-tuned via structural modifications. These display quite high Stokes shift (≥5991 cm−1) in solution and aggregated/solid state. Further, these derivatives display faint emission in solution (THF), while bright yellow [λem; 560 nm (DQB1)] and intense red [λem; ∼650 nm (DQB2)] in aggregated state with good quantum yield [Φf; 17.5 (DQB1) and 23.2 (DQB2)], and represent a family of dye with good AIE characteristics. Both the systems display superior solid state emission and crystallization-induced red-shifted emission. It has been shown that the compounds under study exhibit multi-responsive characteristics toward external stimuli, particularly significant color tuning in solid state due to mechanical stress and acid/base vapors. Crystal structure analyses for both DQB1 and DQB2 revealed efficient J-type aggregation and vital role of the intermolecular interactions toward AIE and multi-responsive properties. Through this work, we describe strategic design, synthesis, thorough characterization, and detailed photophysical properties of quinoxaline-based BODIHY conjugates (DQB1 and DQB2) displaying efficient AIE, good solid-state emission, viscosity-induced emission, crystallization-induced red-shifted emission and multi-stimuli responsive properties. [Display omitted]