Abstract A new Cu(II) complex with flavonoxylacetate ligand was synthesized and characterized. The structure of the complex was determined by X-ray single crystal diffraction technique. In the crystal structure, flavonoxylacetate coordinates Cu(II) ion in bidentate mode resulting in a chelating pentagonal coordination structure. Central Cu(II) has an elongated octahedral coordination showing a strong Jahn-Teller effect. The stability of the crystal structure was investigated by thermal gravimetric analyses. The loss of coordination water in crystals occurs above 150 °C. Fluorescence spectra are affected by pH value and coordination metal ion as well as the substitution pattern of the carboxymethoxy on the flavone skeleton. Furthermore, the fluorescence quenched in the Cu(II) complex recovered with increase of S2- ion concentration. Graphical Abstract

中文翻译：

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具有黄酮氧基乙酸酯配体的铜 (II) 配合物的合成、晶体结构和光谱特性

摘要 合成并表征了一种具有黄酮氧基乙酸酯配体的新型Cu(II)配合物。通过X射线单晶衍射技术确定了配合物的结构。在晶体结构中，黄酮氧基乙酸酯以双齿模式配位 Cu(II) 离子，从而形成螯合五边形配位结构。中央铜 (II) 具有拉长的八面体配位，显示出强烈的 Jahn-Teller 效应。通过热重分析研究了晶体结构的稳定性。晶体中配位水的损失发生在 150 °C 以上。荧光光谱受pH值和配位金属离子以及黄酮骨架上羧基甲氧基的取代模式的影响。此外，随着 S2- 离子浓度的增加，Cu(II) 复合物中淬灭的荧光会恢复。