基于偶氮苯衍生物光响应及阴离子响应的研究

发布时间：2018-11-24 11:39

【摘要】：有机小分子凝胶具有响应外界刺激,如光、电、磁、超声波和离子刺激等,从而呈现出不同的物理、化学性质,其在化学传感器、分子识别等领域具有潜在的应用前景。本论文从分子设计出发,设计并合成了含联酰胺基元的偶氮苯衍生物(BNB-t4)和含1,3,4-VA二唑基元的偶氮苯衍生物(AOB-t4)。系统研究了这两类化合物的有机凝胶行为、光响应行为和阴离子响应行为,分别获得了具有光响应的有机智能凝胶和具有离子识别能力的分子传感器,揭示了其响应的微观机制。具体内容如下:1、合成了以偶氮苯与1,3,4-VA二唑为刚性基元、以烷氧基为尾端取代基的楔形偶氮苯衍生物BNB-t4和AOB-t4。通过核磁共振氢谱、红外光谱和元素分析对其分子结构进行了表征和确认。2、AOB-t4在中等极性溶剂,如二氯甲烷、氯仿和丙酮中可以形成稳定的凝胶。通过红外光谱,紫外可见吸收光谱等证明,分子间氢键、偶氮苯的π-π堆积及烷基链间范德华力的协同作用是凝胶因子形成凝胶的原因。此外,AOB-t4的二氯甲烷凝胶具有良好的光响应能力,研究发现用365nm的紫外光对AOB-t4的二氯甲烷凝胶进行照射,可导致自组装结构的转变及凝胶的坍塌。因此,紫外光诱导的AOB-t4从trans-到cis-的异构化及其引发的分子间作用力变化是凝胶坍塌的主要原因,凝胶-溶胶的转变微观上对应着纤维-颗粒的形貌转变,并诱导了分子排列方式的变化及聚集态的荧光增强。3、BNB-t4在苯、甲苯、二氯甲烷、氯仿等中等极性有机溶剂中可以形成稳定的橘黄色不透明凝胶,在极性较大的溶剂中完全溶解,不溶于非极性溶剂。同时,BNB-t4溶液可以通过“裸眼”和光谱变化选择性地对F-、H2PO4-和AcO-进行识别。分析表明,BNB-t4与阴离子结合主要是通过氢键作用( NH和 OH)实现质子化与去质子化的过程。另外,BNB-t4与F-的溶液中加入HSO4-能使溶液恢复原有的性质,从而实现了分子检测功能的可逆性,为构筑新型分子逻辑门提供了依据。
[Abstract]:Organic small molecular gels exhibit different physical and chemical properties in response to external stimuli, such as light, electricity, magnetic, ultrasonic and ion stimuli. They have potential applications in chemical sensors, molecular recognition and other fields. Based on molecular design, azobenzene derivatives (BNB-t4) and azobenzene derivatives (AOB-t4) containing biamide-unit were designed and synthesized. The organic gel behavior, photoresponse behavior and anion response behavior of the two compounds were systematically studied. The organic smart gel with photoresponse and the molecular sensor with ion recognition ability were obtained, respectively. The micro mechanism of its response is revealed. The main contents are as follows: 1. The wedge-shaped azobenzene derivatives BNB-t4 and AOB-t4. were synthesized with azobenzene and 1 azobenzene as rigid unit and alkoxy as tail substituent. The molecular structure was characterized and confirmed by NMR, IR and elemental analysis. 2AAOB-t4 can form stable gel in medium polar solvents such as dichloromethane, chloroform and acetone. It was proved by IR and UV-Vis absorption spectra that the formation of gel was due to the interaction of intermolecular hydrogen bond, 蟺-蟺 stacking of azobenzene and van der Waals force between alkyl chains. In addition, the dichloromethane gel of AOB-t4 has good photoresponse. It is found that UV irradiation of 365nm can lead to the transformation of the self-assembled structure and the collapse of the gel. Therefore, the isomerization of AOB-t4 from trans- to cis- induced by ultraviolet light and the change of intermolecular force initiated by it are the main causes of gel collapse. It also induced the change of molecular arrangement and fluorescence enhancement of aggregation state. 3BNB-t4 can form stable orange opaque gel in benzene, toluene, dichloromethane, chloroform and other medium polar organic solvents. It is completely dissolved in the more polar solvent and insoluble in the non polar solvent. At the same time, F-H2PO4- and AcO- can be selectively recognized by BNB-t4 solution through "naked eye" and spectral changes. The results show that the binding of BNB-t4 to anions is mainly through hydrogen bonding (NH and OH) to realize protonation and deprotonation. In addition, the addition of HSO4- to the solution of BNB-t4 and F- can restore the original properties of the solution, thus realizing the reversibility of the molecular detection function, which provides the basis for the construction of a new molecular logic gate.
【学位授予单位】：河南大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：O648.17;O621.13

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