【作者】 薛鹏冲；

【导师】 王宗睦； 卢然； 赵英英；

【作者基本信息】 吉林大学 ， 有机化学， 2005， 博士

【摘要】 本论文设计合成了一系列含胆固醇基团的小分子有机凝胶剂,并详细地研究了它们在有机溶剂中形成凝胶的能力及其性质,并以凝胶为模板构筑了多种形貌不同的无机纳米结构,获得了一些创新性的结果。主要内容包括: 合成并研究了胆固醇取代双水杨醛西佛碱衍生物在有机溶剂中的凝胶性质,结果发现,在苯/环己烷凝胶中分子通过单分子层的层状堆积形成片状结构。在紫外光照射下凝胶发出很强的绿色荧光,而溶胶几乎不发光,凝胶材料表现出荧光增强现象,是由凝胶状态下分子运动受到限制和发色团形成J-聚集体引起的。合成并研究了一系列胆固醇取代双西佛碱衍生物在有机溶剂中的凝胶性质,发现它们的凝胶性质具有与分子构型相关的奇偶性,并以其中两种凝胶为模板分别合成了不同形貌的金和银纳米线,以及螺距不同的CuS纳米线。合成了酰氨基取代双胆固醇衍生物,研究了它在有机溶剂中的凝胶性质,发现分子在乙醇凝胶中通过双分子堆积模式自组装形成一维纳米纤维,并以此纤维为模板合成了直径约60 nm 的项链形多孔CdS 纳米线,详细研究了CdS 的矿化机理,首次发现体系中游离的凝胶剂分子在CdS矿化过程中起到了重要作用。设计并合成了新型双胆固醇取代紫精衍生物,研究了其在有机溶剂中的凝胶性质,结果表明分子在凝胶中通过折叠构型的层状堆积自组装形成很长的纤维,以此凝胶纤维为模板合成了内径不同的SiO2 纳米纤维,首次发现在强催化剂下,凝胶纤维的堆积在转录过程中能发生重排,由层状结构变成六方堆积,而在弱催化剂下,凝胶纤维的层状堆积保持不变。利用N-十二酰丙氨酸钠形成的溶致液晶相为模板合成了结构新颖的CdS 纳米结构,并发现在模板合成无机纳米结构时,同一分子在不同条件下可以充当不同的模板,分别得到多孔的CdS 纳米结构、内部多孔外壳实心的CdS 纳米棒以及形貌不同的纳米棒。更多还原

【Abstract】 Nowadays, the design, synthesis and study of gelation properties of low-molecular-weight gelators have been received much attentions because of the diversity of structures of gelators, which may induce the gelators to self-assemble into various dimensional and morphologic suparstructures in organic solvents directed by nanocovalent interactions such as H-bonding, van der Walls, π-πstacking ect. We may construct functional organogel with special nanostructures through introduction some functional groups to the organogelators. The organogels have numerous potential applications in hardeners of solvents and drug delivery systems. Very recently, organogels were applied as novel media to produce various inorganic nanostructures, such as linear fibers, lamellar and helical fibers structures, which give us an opportunity to prepare various novel inorganic nanomaterials. We synthesized several organogelators consisting of cholesterol groups and investigated their gelation properties, furthermore, used their gels as templates to produce various inorganic nanomaterials. Some creative results were obtained. The main results were outlined as following: (1) Dicholesterol derivative consisting of salicylideneaniline moieties was synthesized, and its gelation property was studied in organic solvents. It was found that it was good gelator and the organogelators packed with unimolecular repeating layer into lamellar structure. Moreover, strong green fluorescence in gel state could be observed and very weak fluorescence in sol state was invisible by our naked eye. This enhanced fluorescence emission was ascribed to the restriction of the molecular motions and the formation of J-aggregate. (2) Synthesis and gelation properties of a series of dicholesterol derivatives consisting of Schiff’base moieties were investigated. It found that their gel abilities possessed obvious odevity, which was related with their chemical structures. Moreover, we successed in constructing CuS nanofibers with different helical pitches, and firstly affirmed that binding sites between metal ions and gel fibers could be tunned by the solvent, which induced the difference of morphologies of inorganic nanostructures. (3) A organogelator of cholesterol derivative with amide groups was synthesized. Gelator self-assembled into one-dimensional nanofibers with dimolecular repeating layer in ethanol. The CdS nanofibers with an approximate 60 nm outer diameters and 4-6 nm inner diameters were prepared using organogel fibers as template. On one hand, one can obtain useful information on how the gel molecule and inorganic precursor interacted, which induced the transformation of the arrangement of gelator molecule. On the other hand, it was confirmed that the formation of pearl-necklace CdS nanofibers consisting of porous network particles was on base of the更多还原