【作者】 邢春勇；

【导师】 张文勤；

【作者基本信息】 天津大学 ， 有机化学， 2010， 博士

【摘要】 荧光分子开关作为超分子化学的重要组成部分，近年来得到了快速发展并成为各国化学家的研究热点。本论文旨在合成苯并噁唑荧光受体，在该类物质的功能性分子设计、金属离子识别方面开展研究。合成了一系列含有苯并噁唑荧光基团的氧杂和氮杂18-冠-6醚以及开链聚醚分子探针，通过金属离子滴定测试了它们的荧光光谱变化，测试结果表明，这两个冠醚化合物对常见金属阳离子虽然都有一定的络合作用，但是没有特定的选择性。金催化下的有机化学反应近几年成为研究的热点，近年来，随着对金催化剂研究的逐步深入，发现金催化剂在催化反应中具有的较高催化活性和较高的反应选择性，例如在氢化反应，氧化反应，以及环化反应中，都表现出了与传统催化剂不一样的特点。我们通过应用密度泛函理论（DFT），在B3LYP水平下，探讨了配体对于Au(Ⅰ)配合物和芳卤进行氧化加成反应的影响，为设计合成高催化活性的Au(Ⅰ)催化剂提供理论依据。我们设计了Au(Ⅰ)配合物和芳卤氧化加成的反应模型并计算了它们反应势能图。在芳卤和三个Au(Ⅰ)配合物[Au(ppy)]、[Au(dpe)]+和[Au(NHC)Cl]的氧化加成反应中，与[Au(ppy)]的反应能垒最低。这主要是由于富电子的N原子在氧化加成过程中可以与金原子中心配合，大大稳定了反应的过渡态TSppy(2-3)和氧化加成产物3ppy。对于阳离子Au(Ⅰ)配合物[Au(dpe)]+，由于它的缺电子性质，导致了它和芳卤进行氧化加成时要经历的过渡态TSdpe(2-3)和氧化加成产物3dpe的相对吉布斯自由能都比较高，使得氧化加成反应的能垒和产物的稳定性大大降低，不利于反应的顺利进行。由于线性的[Au(NHC)Cl]与芳卤进行氧化加成反应时需要一个很大的变形能，使得反应的能垒急剧升高，阻碍了反应的进行。更多还原

【Abstract】 As an important branch of the supermolecular chemistry, the fluorescence mo-lecular switch has developed rapidly and attracted interests by the chemists. In thisdissertation, the functional design and the molecular recognition of benzoxazole fluo-rescent receptors were studied.A series of fluorescent probes with double benzoxazole fluorescen groups linkedcrown ether or open chain polyester were designed and synthesed. According to themetal ion titration test, it was found that there is no good selectivity to the particularmetal ion and the further identification was given up.Gold catalysts have attracted considerable interests in recent years because oftheir high activity and selectivity in catalyzed reactions. They showed different chrac-teristics in many reactions, such as hydrogenation, oxidation and cycloaddition reac-tions, etc.Here, DFT calculations under B3LYP were performed to investigated the role theligands affecting the oxidative addition reaction of the aryl halides to Au(Ⅰ) complexes.We provide a theoretical basis for the catalysts designing. The results show that thecomplex [Au (ppy)] is prefer to the oxidative addition reactions of aryl halide com-pared to the complexes [Au(dpe)]+and [Au(NHC)Cl]. The coordination of elec-tron-rich nitrogen to gold center play a key role to stabilize the transition stateTSppy(2-3)and the oxidative addition products3ppy. The electron-deficient feature ofcomplex [Au(dpe)]~+increase the relative energies of the transition states TSdpe(2-3)andthe oxidative additive products3dpe. For the complex [Au(NHC)Cl], the great defor-mation-energies result in the very high barriers for the oxidative addition reactions ofaryl halide.更多还原