新型席夫碱型液晶冠醚的合成与性质  

Synthesis and Properties of Schiff Base Crown Ether Liquid Crystals

作　　者：张淑媛[1] 何可可[2] 郑世军[2] 王永欣[2] 张宝国[1] 李自法[2] 

机构地区：[1]郑州大学化学系,郑州450052 [2]郑州大学材料工程学院,郑州450052

出　　处：《应用化学》2005年第3期272-277,共6页Chinese Journal of Applied Chemistry

基　　金：国家自然科学基金(29974026);河南省自然科学基金(0211021100);河南省教育厅自然科学基金(20021500004)资助项目

摘　　要：以4-(4'-烷氧基联苯基-4-羧基)苯甲醛和二氨基二苯并-15-冠-5为原料,通过溶液缩合反应,合成了一系列席夫碱型液晶冠醚,产率为95.2%～96.7%,产物经元素分析、旋光仪、核磁共振、红外光谱、基质辅助激光解析电离飞行时间质谱、示差扫描量热法和偏光显微镜测试技术进行了表征. 化合物6Ⅰ和6Ⅱ加热至熔点以上都能形成液晶态,可以观察到手性近晶C相、近晶相、胆甾相和向列相的典型织构. 随分子末端烷氧基碳原子数增加,化合物的熔点(Tm)和液晶态的清亮点(Ti)递减,近晶相范围渐增,而近晶相-向列相转变温度和向列相温度范围递减.A series of novel Schiff base crown ether liquid crystals were synthesized from intermediates 4-(4′-alkoxylbiphenyl-4-carboxyl)benzaldehyde and diaminodib enzo-15-crown-5 in yields of 95.2%～96.7%, and their structures and propert ies were characterized by elemental analysis, polarimetry, 1H NMR, IR, MAL DI-TOF-MS, DSC and polarizing optical microscopy with a heating stage. It was found that end products 6Ⅰ and 6Ⅱ formed liquid crysta lline phase when heated to their melting points. In their liquid crystalline state, typical chiral smectic C phase, smectic phase, cholesteric phase, an d nematic phase textures can be observed. The smectic phase temperature rang e increases, but the smectic-nematic transition temperature and nemetic pha se temperature rang decrease with the increasing of the carbon number of end alk oxy groups, and the melting point(T_m) and isotropization temperature( T_i) decrease gradually.

关 键 词：席夫碱 冠醚 热致性液晶 合成 

分 类 号：O625.5[理学—有机化学]