2-羟基-1-萘甲醛缩-2-萘甲酰腙对Zn2+的选择性识别

设计合成了识别Zn²⁺的荧光传感分子--2-羟基-1-萘甲醛缩-2-萘甲酰腙(3)。 通过红外光谱、核磁共振谱和质谱测试技术表征了其结构。 利用其光谱性质研究了该物质对几种过渡金属离子的识别性质，初步探讨了其结合模式。 结果表明，在乙腈介质中，受体分子3表现出对Zn²⁺良好的选择性，Zn²⁺的加入导致受体分子3的吸收光谱在435 nm处出现1新峰，其吸光度逐渐增强，同时于239、302、330、342和387 nm处观察到5个清晰的等吸收点；在516 nm处荧光增强101倍，而其它过渡金属只引起受体分子]3的荧光略微增强。 Job法实验揭示受体分子3与Zn²⁺的结合比为1∶1。

Selective Recognition of Zinc Ion by N'-((2-Hydroxynaphthalen-1-yl)methylene)-2-naphthohydrazide

A fluorescent chemosensor, N′-((2-hydroxynaphthalen-1-yl)methylene)-2-naphthohydrazone(3), was designed and synthesized. Compound 3 was confirmed by IR, 1H NMR and ESI-MS. Compound 3 was investigated to recognize transition metal ions such as Zn²⁺, Cd²⁺, Cu2+, Hg²⁺, Pb²⁺ and Ni²⁺ via the fluorescence spectroscopic method. Mechanism of enhancement of the fluorescence of compound ]3 by Zn²⁺ was briefly discussed. The experiments show that acceptor 3 has a good selectivity of Zn²⁺ in acetonitrile. A new peak in the absorption spectrum of acceptor 3 at 435 nm appears for the addition of Zn²⁺ with the gradually increasing absorbancy, while five clear absorption points can be observed at 239, 302, 330, 342 and 387 nm, respectively. The fluorescence of acceptor 3 shows a highly selective response to Zn2+only. In acetonitrile Zn²⁺ induced a dramatic enhancement in the fluorescence of acceptor 3 by 101 folds at 516 nm, whereas the other transition metal ions had little influence on the fluorescence of acceptor 3. Job′s test showed acceptor 3 coordinated to Zn²⁺ to form a 1∶1 model complex.