Synthesis, mesomorphic and fluorescent properties of 1,3,4-oxadiazoles/thiadiazoles with a terminal 3-fluoro-4-cyanophenyl group
作者:Wen-Yue Zhong、Le-Qian Song、Bin Zhou、Hao-Tian Zhou、Hao-Sen Sun、Huacheng Zhang、Jie Han
DOI:10.1016/j.tet.2023.133579
日期:2023.9
A series of new liquid crystalline 1,3,4-oxa/thiadiazoles with a terminal 3-fluoro-4-cyanophenyloxy group were synthesized, and their structures were characterized by nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESI-MS). The liquid crystal properties were studied by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). All of the 1,3,4-oxadizoles
合成了一系列末端带有3-氟-4-氰基苯氧基的新型液晶1,3,4-氧杂/噻二唑,并通过核磁共振(NMR)和电喷雾电离质谱(ESI-MS)对其结构进行了表征。 )。通过差示扫描量热法(DSC)和偏光光学显微镜(POM)研究了液晶特性。所有1,3,4-恶二唑仅表现出向列中间相,而1,3,4-噻二唑类似物在较宽的温度范围内表现出近晶A (SmA) 和近晶C (SmC)。使用紫外可见分光光度计(UV-Vis)和荧光光谱仪研究了荧光特性。所有最终化合物在 CH 2 Cl 2中的溶液分别显示出一个带有 λ 的吸收带其abs-max值在319-340 nm处,并且在432-448 nm处表现出强烈的发射,λ em-max值在432-448 nm处,光致发光量子产率达到0.52-0.66。比较讨论了杂环结构单元、末端烷氧基链长和侧氟原子对液晶和荧光性能的影响。