液晶化合物戊基偶氮苯甲醛光反应动力学及其与金属离子作用  

Study on the Photo-Reaction Kinetics of Liquid Crystalline Compound Pentyl Benzoxy Benzaldehyde and Its Interaction with Metal Ions

作　　者：郑敏燕[1] 魏永生[1] 古元梓[1] 侯雅慧 袁戈 Zheng Minyan;Wei Yongsheng;Gu Yuanzi;Hou Yahui;Yuan Ge(College of Chemistry and Chemical Engineering,Xianyang Normal University,Xianyang,Shuanjri 712000,China)

机构地区：[1]咸阳师范学院化学与化工学院,陕西咸阳712000

出　　处：《化学世界》2020年第4期260-266,共7页Chemical World

基　　金：国家自然科学基金(No.21102121);国家级大学生科研创新训练计划(No.201710722003);咸阳市科技局科学技术研究计划(No.2017k02-19)资助项目。

摘　　要：分别以甲醇、四氢呋喃为溶剂,利用紫外光谱,研究了液晶化合物4-[4-(4-戊基苯酰氧)苯偶氮]苯甲醛光异构化正反应(紫外光照)、逆反应(日光照射)的动力学过程,以及该偶氮化合物样品与常见金属离子(不同浓度)之间的相互作用;利用循环伏安法(CV)对化合物在紫外光照(正反应)、日光照射(逆反应)不同时间时的电化学性质变化进行了研究。结果表明,该化合物在365 nm紫外光照/日光照射下,可进行反顺异构化及其逆过程,其正逆反应均为二级速率过程。光稳态顺式结构在四氢呋喃(THF)溶液中,质量分数为15.0%,转化率为16.2%;在甲醇溶液中,质量分数为9.0%,转化率为8.7%,表明极性较强的甲醇溶液中,顺反异构化过程较难进行。不同金属离子对该偶氮样品光异构化过程有影响,其中影响最显著的为氯化铜。循环伏安法研究表明,该化合物在不同溶剂体系中发生氧化或还原反应的程度和强度均有较大差异。Kinetic process of photoisomerization of liquid crystalline compound,4-[4-(4-n-pentyl benzoyloxy)phenylazo]benzaldehyde,under UV and sunlight irradiation were studied by UV spectroscopy using methanol and tetrahydrofuran as solvents.Cyclic voltammetry(CV)was employed to investigate the changing of electrochemical properties of the compound under UV(positive reaction)and sunlight(negative reaction)irradiation.The results showed that the compound could be trans-cis-isomerized under ultraviolet irradiation of 365 nm or sunlight,and the positive and negative reactions were secondary rate processes.In Tetrahydrofuran(THF)solution,the content of cis-structure was 15.0%and the conversion was 16.2%,while in methanol solution,its content was 9.0%and the conversion was 8.7%.It is demonstrated that trans-cis isomerization is difficult in methanol solution due to high polarity.Different metal ions also affect the photoisomerization of azo sample,and the most significant one is copper chloride.Cyclic voltammetry results showed that the extent and intensity of oxidation or reduction reactions in different systems were quite different.

关 键 词：偶氮液晶 反应动力学 循环伏安法 紫外光谱 

分 类 号：O625.4[理学—有机化学]