Synthesis of functionalized triphenylene discotic liquid crystals and the influence of unsaturated periphery on mesomorphism  

作　　者：ZHAO KeQing ZHOU Hui YU WenHao HU Ping WANG BiQin MONOBE Hirosato SHIMIZU Yo 

机构地区：[1]College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610066, China [2]National Institute of Advanced Industrial Science and Technology, Kansai Centre, Midorigaoka, lkeda, Osaka 563-8577, Japan

出　　处：《Science China Chemistry》2011年第10期1576-1583,共8页中国科学（化学英文版）

基　　金：supported by the National Natural Science Foundation of China (50973076 & 51073112)

摘　　要：Twelve triphenylene discogens with unsaturated periphery (abbreviated as C18H6(OC5H11)6-x(OR)x(x=1,2,3), R=-C3H6CH==CH2(a),-C3H6C≡CH(b),-C2H4OCH==CH2(c)) were synthesized and characterized. The thermotropic liquid crystal prop-erties were studied by using polarized optical microscopy, differential scanning calorimetry and X-ray diffractometry. The results showed that all triphenylenes exhibited hexagonal columnar mesophase. The thermotropic studies showed that series a (alkene periphery) exhibited higher clearing points than the corresponding series b (alkyne periphery), while series c (vinyloxy periphery) exhibited highest clearing points and widest mesophase temperature ranges. We also found that the symmetric discogens sym-C18H6(OC5H11)3(OR)3 displayed higher melting points and clearing points than the asymmetric ones asym-C18H6(OC5H11)3(OR)3.Twelve triphenylene discogens with unsaturated periphery （abbreviated as C18H6（OC5H11）6-x（OR）x（x=1,2,3）, R=–C3H6CH==CH2（a）,–C3H6C≡CH（b）,–C2H4OCH==CH2（c）） were synthesized and characterized. The thermotropic liquid crystal prop-erties were studied by using polarized optical microscopy, differential scanning calorimetry and X-ray diffractometry. The results showed that all triphenylenes exhibited hexagonal columnar mesophase. The thermotropic studies showed that series a （alkene periphery） exhibited higher clearing points than the corresponding series b （alkyne periphery）, while series c （vinyloxy periphery） exhibited highest clearing points and widest mesophase temperature ranges. We also found that the symmetric discogens sym-C18H6（OC5H11）3（OR）3 displayed higher melting points and clearing points than the asymmetric ones asym-C18H6（OC5H11）3（OR）3.

关 键 词：discotic liquid crystal TRIPHENYLENE functional periphery hexagonal columnar mesophase mesomorphism engineering 

分 类 号：O753.2[理学—晶体学] TQ323.42[化学工程—合成树脂塑料工业]