【摘要】 以丁二酸胆甾醇单酯(CSA)作为质子给体,以4-对烷氧基苯甲酰氧基-4′-苯乙烯基吡啶(NCn)作为质子受体,通过羧酸和吡啶之间的氢键作用形成氢键诱导液晶化合物(CSA·NCn)。利用紫外光谱研究了含苯乙烯基吡啶基团的液晶化合物NCn及其与丁二酸胆甾醇单酯(CSA)的氢键复合物CSA·NCn在溶液中的光致变色及光化学反应。结果表明,在乙醇溶液中紫外光照射下二者均发生顺反异构化,分子间氢键对顺反异构化反应没有太大的影响;NCn化合物在氯仿溶液中,紫外光照射下发生光化学反应,而CSA·NCn的氯仿溶液,紫外光照射下只发生顺反异构化,这一方面说明光化学反应发生在吡啶的氮端,同时也表明这类氢键液晶化合物中的氢键比较稳定,光照下不发生解离;在NCn和CSA·NCn的乙醇溶液中加入H2SO4,两者均发生质子化。表明强酸可以破坏CSA·NCn化合物中的氢键,使含吡啶端基解离出来,同H+发生质子化。更多还原

【Abstract】 A new type of liquid crystalline was formed through self-assembly via intermolecular hydrogen bonding between the carboxylic acid and the pyridyl group of the stilbazoles.Cholesteryl butane diacid single ester(CSA) was synthesized for use as H-bond donor and the stilbazole derivatives(NCn) were prepared as H-bond acceptors.The spectroscopic behavior and the photochemical stabilities of these two compounds,NCn and its intermolecular H-bonding complex CSA·NCn were investigated by UV-Vis spectroscopy.The results show that these two compounds easily undergo photoisomerization from trans to cis isomers in alcohol.In chloroform solution,the CSA·NCn only undergoes trans-cis photoisomerization,while NCn exhibits not only trans-cis isomerization but also a special photoreaction.The reason is that in CSA·NCn compounds,the pyridyl N-end group is forms intermolecular H-bonding with CSA,and can’t catch the H+ and the radical.It is proved that this intermolecular H-bond was very stable when being exposed to UV light.更多还原