【作者】 韩辉；

【导师】 韩相恩；

【作者基本信息】 中国矿业大学 ， 应用化学， 2015， 博士

【摘要】 喹喔啉环的平面性和刚性共轭结构使其具有独特的光学和电学性质,基于此特性而被广泛应用于电致发光,光致发光和光发射掺杂等领域。喹喔啉衍生物在抗HIV、抗结核、抗肿瘤、抗炎、抗病毒、抗原生动物、驱虫药、抗癌和抗细菌等方面也表现出广阔的生物活性。喹喔啉类衍生物的合成与应用拓展是其重要的研究方向之一。锌离子是生命体中不可获取的微量元素,参与了许多的生命活动,因此,在生命和环境科学等领域对锌离子进行检测具有重要的应用前景以及学术价值。荧光探针因具有较低的成本、简便的操作和高的灵敏度等优点而受到广泛关注。对锌离子荧光探针来说,其分子设计通常基于具有优良荧光性质的杂环作为发色团,采用吡啶,吡咯和噻吩等结构的组合作为识别基团。其中喹喔啉化合物作为识别基团或荧光基团用于锌离子荧光探针方面的研究很少有文献报道。因此,基于喹喔啉类衍生物优异的荧光性质和氮原子的配位性能,本文系统性地设计和合成了一系列二吡啶基喹喔啉和二喹啉基喹喔啉衍生物,研究其作为锌离子荧光探针的性能,并通过高斯软件对所有探针结构进行了优化,通过优化后得到的电子云空间分布与分子轨道能级讨论了探针结构与性能的关系。第一章,详细介绍了荧光探针的识别机理、喹喔啉类荧光材料的研究进展、锌离子荧光探针的发展和本文的研究思路。第二章,以单质碘为催化剂,以邻羟基酮和邻苯二胺衍生物为起始原料,创新性地‘一锅合成’喹喔啉类化合物,对相关的条件进行了讨论,该反应具有条件温和,反应速度快,催化剂毒性小和反应产率高等优点。第三章,以2,3-二(2’-吡啶基)喹喔啉衍生物作为识别基团和荧光基团,通过改变6-位的取代基,合成了一系列锌离子荧光探针(QP1-QP5),结果表明,羟甲基,甲氧酰基和甲氧基等给电子基团引入增强了其作为锌离子探针的性能,探针QP3-QP5和锌离子的结合都导致了荧光发射光谱的红移和强度的增强,并且该类探针表现出对锌离子强的选择性和灵敏度,荧光识别的机理是分子内电子转移。第四章,通过在2,3-二(2’-吡啶基)喹喔啉的6-位引入氨类化合物,得到三个氨类基团取代的锌离子探针(QP6-QP8),该类探针表现出与预测完全相反的锌离子识别荧光特性。该类探针与锌离子结合,导致了荧光光谱的不完全淬灭,饱和的锌离子条件下,该类探针荧光强度淬灭大约3/5。PET过程的禁断与允许是该类锌离子识别荧光现象的机理,这个与传统意义上禁止PET过程产生而得到的荧光增强型探针性能相反。由于氨类基团的强给电子作用,使得该类基团对锌离子具有低的检测限,达到10-12数量级。第五章,本章通过扩展该类2,3-二(2’-吡啶基)喹喔啉识别基团的共轭结构,利用偶联反应6-位引入苯基、联苯、萘和噻吩基团合成了一类喹喔啉衍生物(qp9-qp12),并将其用于锌离子检测,研究表明,该类化合物也都具有较好的锌离子检测性能,锌离子的加入都导致了荧光发射光谱的增强。另外,除了探针qp11,其它探针与锌离子结合后,其溶液颜色由淡青色变为黄色,根据此现象,可实现对锌离子的‘裸眼’定性检测,其荧光增强的识别机理也是分子内电荷转移。第六章,通过witting反应在2,3-二(2’-吡啶基)喹喔啉的6-位引入三甲氧苯基和三苯胺基,意外地得到了一类可以用来检测有机溶剂中水含量的探针(qp13和qp14),该类探针在质子化的有机溶剂中呈现荧光完全淬灭的性质,它们的非质子化有机溶液的荧光强度会随着水含量的增多而逐渐下降,荧光发射峰的位置不变,其原因可能是激发态的电荷分离导致给电子基团一端形成氢键的能力增强而发生了电子的快速迁移所致,研究表明,该类探针对dmf和丙酮中水含量的检测具有很好的效果,响应速度快,检测范围宽,小于0.1%的水含量时,探针溶液荧光强度近似线性变化,检测限达到了ppm。水含量的检测范围与给电子一端可形成氢键的个数有关,氢键个数越多检测范围越宽。第七章,合成了两个新型的双喹喔啉类锌离子荧光探针qp15和qp16,研究表明,这两个探针对锌离子也表现出荧光增强的比率响应,但两个探针的荧光发射峰的位置出现红移和蓝移两种不同的特性,可能是不同的取代基导致了两种特性,从而使得识别基团在分子整体上表现出推-拉电子的不同,也就是出现了红移和蓝移两个不同的变化;另外,在锌离子检测方面,探针qp15和qp16也表现出良好的灵敏度和选择性。第八章,为了进一步的改善该类探针的性能,以二喹啉基喹喔啉作为新的识别基团的荧光探针被设计和合成(qp17-qp20),该类探针将吡啶环用喹啉环代替,喹啉环具有优良的共轭结构和荧光特性,并被广泛应用于有机光学材料领域,它的引入希望能够制备一类具有优良特性的锌离子探针。结果表明,该类探针性能符合预期,与结构相似的吡啶基喹喔啉类探针相比,具有低一个数量级的检测限,选择性也较好,其中qp18的荧光光谱在加入饱和锌离子前后,荧光强度增大了300倍左右,远远高于吡啶基喹喔啉探针的相应数据,是一类具有更广阔的应用前景的探针材料。第九章,对全文的工作进行了总结,对喹喔啉类衍生物在荧光探针方面的应用前景进行展望。更多还原

【Abstract】 Quinoxaline ring has unique optical and electrical properties as a result of the flat and rigid conjugated structure, so its derivatives have been applied to electroluminescence, photoluminescence and light emitting dopant fields. In addition, Quinoxaline derivatives exhibit a broad biological activity in the anti-HIV, antituberculosis, anti-inflammatory, anti-tumor, anti-viral, anti-protozoan, anthelmintics, anti-cancer and anti-bacterial etc. Moreover, synthesis and application of quinoxaline derivatives are one of the important research direction. Zinc is an essential trace element in the living body and involves a lot of life activities, thus the detection of zinc ion has important academic value and application prospects in the life sciences and environmental science research. Fluorescent probes have attracted considerable attention due to a lower cost, easy operation and high sensitivity. Zinc ion fluorescent probe, its molecular design is usually based on having excellent fluorescence properties as a combination of a heterocyclic chromophore, using pyridine, pyrrole and thiophene structures such as the recognition group. The application of quinoxaline derivatives as the recognition group or fluorophore in fluorescent probes has rarely reported in the literature. Based on excellent fluorescence properties of quinoxaline, a series of pyridyl quinoxaline and quinolinyl quinoxaline derivatives were systematically designed and synthesized to detect zinc ion. The structure of the probe was optimized by Gaussian software, and the relationship between the structure and properties of the probe is discussed by the space distribution of the electron cloud and the molecular orbital energy level.The first chapter introduces the recognition mechanism of fluorescent probes, the development of quinoxaline fluorescent materials and the development of zinc ion probe.Chapter II, quinoxaline derivatives were synthesized by an innovative one-pot method with iodine as a catalyst,o-hydroxy ketone and diamine as a starting material. The influence factors of the reaction are discussed. The reaction system has the advantages of mild conditions, fast response, toxicity catalyst and high yield.Chapter Ⅲ, a series of zinc ion fluorescent probes were synthesized with 2,3-bis(2’-pyridyl) quinoxaline derivatives as a recognition group and a fluorescent group by changing the 6-position substituents. The results show that the performance of probes are enhanced by introducing methyl, methoxy group and methoxyacyl group. The combination of quinoxaline probes and zinc ion have led to red shift and the enhancement of fluorescence strength, and probes exhibit strong selectivity and sensitivity for detectin zinc ion. Mechanism of ion recognition for probes may be intramolecular electron transfer.Chapter Ⅳ, three zinc ion probes substituted were designed and synthesized by introducing ammonia groups in the 6-position of 2,3-bis(2’-pyridyl) quinoxaline. The combination of these probes and zinc ion has led to the quenching of fluorescence spectra, and probes exhibit strong selectivity and sensitivity for detecting zinc ion. The mechanism may be the PET process.Chapter Ⅴ, according to expand the conjugated system of 2,3-bis(2’-pyridyl) quinoxaline, several quinoxaline derivatives were synthesized and were applied to the detection of zinc ion. Results show that these compounds have good performance as zinc ion fluorescence probe. In addition, the solution of the probe and zinc ion turned yellow from colourless liquid that can be utilized to the qualitative detection of zinc ions.Chapter VI, two probes was designed and synthesized by introducing trimethoxyphenyl and triphenylamine in 6-position of 2, 3-bis(2’-pyridyl) quinoxaline. The two probes were used to detect the water content in the organic solution. With increasing water content, the fluorescence intensity of the probe solution gradually decreases. The position of the fluorescence emission peak has not been changed. The reason may be charge-separated excited states lead to the end of the electron-donating group enhanced ability to form hydrogen bonds occurs due to rapid migration of electrons. The results show that the probe has a good efficiency in the detection of water content in DMF and acetone. The response speed is fast, the detection range is wide. When the water content is less than 0.1%, the fluorescence intensity of the probe solution is approximately linear, and the detection limit is reached to ppm. The detection range of the water content is related to the number of hydrogen bonds in the donor group, and the number of hydrogen bond is more, the detection range is wider.Chapter VII, two types of di-quinoxaline zinc ion fluorescent probe was designed and synthesized. The results showed that the two probes also showed enhanced fluorescence ratio response to zinc ion. But the position of the fluorescent emission peak show two different characteristics of red-shift and blue-shift. This difference is attributed to different substituent. The different substituents result in the change of intramolecular electron density. The intramolecular charge transfer is considered as the probe mechanism. In addition, two probes also display a high selectivity and sensitivity for detecting zinc ion.Chapter VIII, in order to further improve the properties of such probes, di quinolinyl quinoxaline derivatives(QP17-QP20) were designed and synthesized. Quinoline has excellent conjugated structure and fluorescence properties. Therefore, we have adopted the structure of quinoline containing pyridine instead of pyridine, and get a series of more excellent probes. The results show that these probes have a lower limit of detection and fluorescence characteristics than the corresponding pyridyl quinoxaline probe. For example, fluorescence intensity of the probe QP18 increased about 300 times after the addition of zinc ion, the detection limit also lows an order of magnitude.Chapter Ⅸ,the work of the full text are summarized, and the future prospect of quinoxaline fluorescence probes for detecting zinc ion was discuss.更多还原