Three novel bent-core liquid crystal compounds (8, 9a and 9b) were prepared with a central bent core based on 2,5-disubstitueted-1,3,4-oxadiazole,ester group bridge (-coo-), alkyl terminal tails, and one side wing substituted by fluorine atom .The structures of the target compounds were confirmed by IR , 1 H NMR, 13 C NMR, MS, and their transition temperatures and phase textures were investigated by using differential scanning calorimet -ric (DSC) and polarizing optical microscopy (POM).The result suggested that all target compounds had right chemical structure .All target compounds exhibited nematic phase and wide temperature range of nematic phase , and the widest range of nematic phase was 78℃.The temperature range of nematic phase of compounds 8 with later-al monofluoro-substituted benzene was more narrow than compounds 9 with lateral difluoro-substituted benzene .%以2,5-二取代-1,3,4-噁二唑为中心核,酯基(-COO-)为桥键,直链烷基为末端基团,在单侧苯环侧位上引入氟原子,设计合成了3个新型不对称弯曲形液晶化合物8,9a和9b;并通过IR,1 H NMR,13 C NMR,19 F NMR和MS对其结构进行鉴定,经差热扫描仪( DSC)和偏光显微镜( POM)测定其液晶相态。结果表明:所有目标化合物的分子结构正确,都呈现向列相态,向列相态温度范围最宽达78℃;侧位单氟苯环结构化合物(8)的向列相温度范围没有二氟苯环结构(9)的宽。
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