Position isomerism of anthracene-based derivatives induced different emission and applications
摘要
Suzuki coupling and Knoevenagel reactions were utilized to design two isomers that contained anthracene and cyanostyrene. The exploration focused on the influence of position isomerism of cyanostyrene on solventochromism, aggregation-induced emission, dual-state emission, mechanochromism, and applications. The isomer bearing a cyano group adjacent to the anthracene core exhibited extremely weak emission in solutions. In contrast, the isomer with the cyano group positioned farther away displayed bright emission and a high fluorescence quantum yield in different solutions. The isomer with the cyano group adjacent to the anthracene core exhibited aggregation-induced emission, whereas the isomer with the cyano group positioned farther away displayed dual-state emission. This difference resulted from a balance between the twisted molecular conformation and the electronic effect. In the solid state, the isomer with the cyano group adjacent to anthracene exhibited a weak yellow emission that showed negligible change upon mechanical force. Contrarily, the isomer with the cyano group far from anthracene exhibited a strong blue emission that displayed a pronounced red-shift upon the same stimulus. The significant difference in mechanochromism behavior for both isomers could be attributed to different intramolecular interactions induced by the adjacent aromatic units. Furthermore, these results demonstrate that both isomers hold promise as candidates for applications in rewritable luminescent paper and bioimaging. As a result, these investigations provided a simple method for constructing functional materials that have distinct properties and broad applications.