新型光可调控联萘酚类手性荧光化学传感器的合成及其应用

Chiral fluorescent chemosensors are the molecules or materials that can interact with the chiral targets and convert the enantioselective recognition events into observably optical signal outputs. The chiral fluorescence sensor have drawn substantial interests of researchers owing to their advantageous features including simplicity, low cost, high sensitivity, adaptation to automation and real-time analysis, and diverse signal output modes. BINOL can be used to construct chiral fluorescent sensors to carry out highly enantioselective, sensitive recognition of chiral amino alcohols, α-hydroxycarboxylic acids, and amino acid derivatives due to their particularities, such as special C2 axial chirality and rigid structure and readily selective functionalization. As an attempt to magnify the fluorescence signal and to further elevate the chiral recognition sensitivities of naphthyls toward chiral analytes, diarylethene derivatives are the most promising candidates for fluorophore of fluorescent sensor. Among all photochromic compounds, diarylethenes are one of the most promising candidates for fluorescence applications owing to their excellent thermal-stability, remarkable fatigue-resistance, rapid response and fairly high photocyclization quantum yields. The chiral switch of BINOL-diarylethene derivatives containing nonconjugated amine groups, schiff-base, bisimidazolium group were synthesized by different reaction such as the click reaction. The light harvesting effect of diarylethene can be used to greatly increase the sensitivity of the fluorescent sensors. Sequentially, a double-check chemosensor system was developed with both fluorometric detection in open isomer as the first check and colorimetric measurement in the photostationary state as the second check. This novel idea facilitates the development of double-check chemosensor for future sensors of chiral molecule and ion racognition.The chiral switch of BINOL-diarylethene derivatives should be used to construct a logic circuit and a molecular keypad lock with UV irradiation, host molecule as inputs.

具有独特光学性质的手性化学荧光传感器不但制作成本低，结构简单，检测灵敏度高，而且比较容易实现高通量及实时的检测，广泛应用于手性化合物和金属离子的识别中。但是一个传感器仅仅只能检测一次，无法实现差异化的两次检测。本项目把联萘酚独特的C2轴手性、刚性结构、易修饰和优异的手性识别能力与二噻吩乙烯良好的热稳定性、显著的抗疲劳性、高量子产率及响应时间短等光开关性质结合起来，设计合成系列不同的连接基团（西弗碱、非共轭胺、咪唑盐和三氮唑等）的新型光致变色环状手性联萘酚全氟二噻吩乙烯化合物。利用联萘酚的手性识别能力以及二噻吩乙烯的光致变色作用，研究开环态和闭环态环状手性荧光传感器对手性氨基酸、α-羟基羧酸和金属离子进行检测，研究大环手性荧光传感器结构、构型、溶剂等对客体分子检测结果的影响，考察联萘酚二噻吩乙烯手性荧光化学传感器的对映体选择性和检测灵敏度，并构建分子逻辑门开关。

高的灵敏度和能直接快速对异构体进行识别与检测，是光学活性的联萘酚(BINOL)衍生物作为荧光化学传感器展示的研究亮点，其特殊的C2轴手性、刚性结构和易修饰的特点，广泛应用于金属离子、阴离子、手性化合物的选择性识别等。手性荧光传感器的主体分子的设计与合成对传感器的识别能力和灵敏度起到决定性作用，把联萘酚独特的C2轴手性、刚性结构、高量子产率、优异的手性识别能力与糖、香豆素、荧光素、二芳烯和甲基喹啉等结合起来，设计合成了16种新型手性联二萘酚荧光探针M1-M16，为手性联二萘酚衍生物合成提供了方法。首先设计合成了一种新型糖基化三氮唑修饰的手性联二萘酚银离子探针，具有低毒性、灵敏度高、抗干扰能力强等特点，在甲醇溶液中实现对Ag+专一性识别。络合常数2.4×106 M-1 (R= 0.997)，检测限很低，达到1.57*10-9 mol/L，可作为特定的高选择性、高灵敏度银离子探针.设计合成了六种新型手性联二萘酚铜离子探针，具有低毒性、灵敏度高、抗干扰能力强等特点，同时实现在甲醇溶液中、乙腈溶液和水溶液对Cu2+有专一性识别作用，可作为特定的铜离子探针，同时通过核磁滴定和红外推断了铜离子识别机理，为铜离子探针结构优化提供依据。设计合成了两种新型手性联二萘酚铁离子探针和半胱氨酸探针，具有低毒性、灵敏度高、抗干扰能力强等特点，实现甲醇溶液中和水溶液中对Fe3+检测。同时探针与铁离子形成的络合物可进一步识别半胱氨酸，络合物稳定，抗干扰能力强，构建了探针-铁离子-半胱胺酸分子识别逻辑门，可作为特定的铁离子探针和半胱氨酸探针检测。还设计合成了两种新型手性联二萘酚锌离子探针和镉离子探针M12和M13，通过Hildebrand-equation方程计算M12与锌离子的络合常数6.65×105 M-1 (R= 0.99)，检测限是1.08*10-6 mol/L；通过Hildebrand-equation方程计算M12与Zn2+的络合常数1.65×105 M-1 (R= 0.997)，检测限是2.08*10-6 mol/L。实现了对银离子、铜离子、铁离子、锌离子和半胱氨酸的微量检测，具有重要的研究意义和广阔的应用前景。