Novel Fluorene-based compounds: Investigation on the synthesis, function and fluorescence mechanism

Fluorene-based compounds are known for their unique role in photoluminescence and electroluminescent materials. Based on this idea, a series of fluorene-based fluorescent compounds were designed and synthesized by the Suzuki coupling reaction. The luminescence effect was evaluated by comparing fluorescence intensity and fluorescence quantum yield of the control compounds. The research indicated that the novel fluorene-based compounds 2,7-di(quinol-4-yl)-9,9-dimethylfluorene(F4) and 2,7-di(indole-5-yl)-9,9-dimethyl fluorene (F5) have better fluorescence characteristics. They are used as sensors for the recognition of nitro compounds and metal ions. In addition F4 has good selectivity and sensitivity to TNP(160600 M-1, 2.63 mu M) and Fe3+ (121140 M-1, 1.68 mu M). Finally, fluorescence quenching mechanism of F4 with TNP was studied by theoretical calculation. (C) 2021 Elsevier B.V. All rights reserved.