A new bis(rhodamine) B hydrazone L, bearing two rhodamine chromophores, has been designed and synthesised in 70 % yield. The chemical structure of the new ligand L was characterised using different spectroscopic techniques. The receptor L was utilised for rapid ‘naked eye’ detection of Fe³⁺, Bi³⁺, Cu²⁺, and Hg²⁺ in THF–H₂O (1 : 1, v/v) by displaying significant colour changes. The mechanism of detection of metal ions was based on the ring-opening of the spirolactam rings of L upon recognition. UV/Vis spectrometry was employed to investigate L–metal ion interactions in THF–H₂O (1 : 1, v/v). The stoichiometries of the complexes were determined using Job’s method, which revealed 1 : 2 L–metal ion stoichiometries in the case of L–(Fe³⁺/Bi³⁺/Hg²⁺) complexes, while a 1 : 1 L–metal ion stoichiometry was recognised for the L–Cu²⁺ complex. ¹H NMR spectroscopy was applied to study the L–metal ion interactions in DMSO-d₆ and results are presented.

设计并合成了带有两个若丹明生色团的新型双（若丹明）B L L，合成产率为70％。使用不同的光谱技术表征了新配体L的化学结构。通过显示明显的颜色变化，受体L用于快速“裸眼”检测THF–H ₂ O（1：1，v / v）中的Fe ³⁺，Bi ³⁺，Cu ²⁺和Hg ²⁺。金属离子的检测机理是基于识别时L的螺内酰胺环的开环。紫外/可见光谱法用于研究THF-H中的L-金属离子相互作用₂ O（1：1，v / v）。确定了复合物的使用工作的方法，该方法显示1所述的化学计量：2 大号在的情况下-金属离子化学计量大号- （铁³⁺ /铋³⁺ /汞柱²⁺）络合物，而1：1的 大号-金属L –Cu ²⁺络合物的离子化学计量被公认。^用1 H NMR光谱研究了DMSO- d _6中的L-金属离子相互作用，并给出了结果。