Synthesis and aggregation induced emission of quinoline-based oligoamide helical foldamers capped with bromobenzene

doi:10.7523/j.issn.2095-6134.2019.05.017

Abstract

Abstract: Two bromobenzene-capped quinoline-based oligoamide foldamers with different lengths and different side chains are designed and synthesized. The compounds have been characterized by UV-Vis, fluorescence spectra, atomic force microscopy (AFM), and scanning electron microscopy (SEM). The results show that the side chains have no effects on the morphology of the aggregated state and the different aggregated morphologies have great influence on the fluorescence intensity. The photoluminescence behavior of the compounds in THF-H₂O binary solvent system and films has been studied, and these compounds display aggregation-induced emissions (AIE). They hardly emit light in the solution state, whereas the photoluminescence intensity in the solid state is several dozen times higher than that in THF-H₂O binary solvent system. This AIE phenomenon is caused by the stable helical structure of foldamers which restricts the intramolecular random rotation of single bonds and intermolecular closest packing. Moreover, the AIE effect of the foldamers is strongly affected by solvents.

Key words: quinoline, oligoamide foldamers, helical, aggregation-induced emission

CLC Number:

TQ617.3

WANG Wentao, LIU Yanwei, MU Wenjing, QI Ting. Synthesis and aggregation induced emission of quinoline-based oligoamide helical foldamers capped with bromobenzene[J]. , 2019, 36(5): 709-715.

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