Tetraphenylethene-based mononuclear aggregation-induced emission (AIE)-active mechanofluorochromism gold(I) complexes with different auxiliary ligands

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Molecular and biomolecular spectroscopy, 2024-11, Vol.321, p.124712, Article 124712
• Main Authors: Deng, Xiao-wen, Liu, Shanting, Fan, Congbin, Liu, Hongliang, Zou, Yijie, He, Hai-feng, Deng, Dian-dian, Pu, Shouzhi, Chen, Zhao
• Format: Article
• Language: English
• Subjects: Aggregation-induced emission; Different auxiliary ligands; Gold(I) complexes; Information encryption; Mechanofluorochromic; Tetraphenylethene
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2024.124712

[Display omitted] •Five tetraphenylethene-containing gold(I) complexes modified with different auxiliary ligands are synthesized.•All these complexes exhibit aggregation-induced emission property.•Complex 1 shows blue-green-cyan three-color fluorescence by sequential mechanical grinding and solvent fumigation.•Complexes 2–5 show reversible mechanofluorochromic behaviors.•An information encryption system is constructed based on tricolored fluorescence feature of 1. In this study, a series of tetraphenylethene-containing gold(I) complexes with different auxiliary ligands have been synthesized. These complexes were characterized using a variety of techniques including nuclear magnetic resonance spectroscopy, mass spectrometry, and single crystal X-ray diffraction. Their aggregation-induced emission (AIE) behaviors were investigated through ultraviolet/visible and photoluminescence spectrum analyses, and dynamic light scattering measurements. Meanwhile, their mechanofluorochromic properties were also studied via solid-state photoluminescence spectroscopy. Intriguingly, all these mononuclear gold(I) molecules functionalized by tetraphenylethene group demonstrated AIE phenomena. Furthermore, five gold(I) complexes possessing diverse auxiliary ligands exhibited distinct fluorescence changes in response to mechanical grinding. For luminogens 2–5, their solids showed reversible mechanofluorochromic behaviors triggered by the mutual transformation of crystalline and amorphous states, while for luminogen 1, blue-green-cyan three-color solid fluorescence conversion was realized by sequential mechanical grinding and solvent fumigation. Based on this stimuli-responsive tricolored fluorescence feature of 1, an information encryption system was successfully constructed.