Synthesis and efficient solid-state emission of conjugated donor–acceptor–donor triphenylamine chromophores

Abstract

Two symmetrical donor–acceptor–donor chromophores built by connecting two triphenylamine donors to a central electron acceptor 2,5-diphenyl-1,3,4-oxadiazole or anthracene core have been synthesized and characterized. The aggregation-induced emission phenomenon of these compounds with bright and deep emission from orange to green in the solid state can be obsreved. The chromophores based on the triphenylamine unit exhibit efficient solid-state emission. The results indicate that D–A–D conjugation bridging provides a new opportunity for AIE-materials. The multiphoton induced fluorescence spectra of these chromophores were measured using a femtosecond Ti:sapphire. The three-photon excited fluorescence spectra are in the green region with peaks at 554 nm for An-BIPAS and 504 nm for Ox-BIASP in THF, respectively. These AIE-active compounds are potential materials to design sensitive and selective fluorescent sensors or bioprobes.