苯丙炔酸和苯丙烯酸酯苯并菲盘状液晶的合成及介晶性

合成了7个含苯丙炔酸和苯丙烯酸酯链的苯并菲盘状液晶化合物C₁₈H₆(OC_nH_2n＋1)₅O₂CR' R'＝C≡CC₆H₅, n＝4～9 (1a～1f); R'＝CH＝CHC₆H₅, n＝6 (1g)]. 该系列化合物结构通过¹H NMR, IR和元素分析表征. 液晶性通过差示扫描量热法和偏光显微镜进行了研究, 结果显示: 化合物均为六方柱状相热致型液晶; 含苯丙炔酸酯链苯并菲盘状液晶化合物1a～1f, 随着烷氧链的增长, 清亮点呈现逐渐下降的趋势; 对于含苯丙烯酸酯链苯并菲化合物1g与具有同样软链长度的炔基酯链苯并菲化合物1c比较, 具有更低的熔点和结晶点, 而它们的清亮点几乎一致, 因而化合物1g有更宽的介晶性温度范围.

Synthesis and Mesomorphism of Triphenylene Discogens with a Phenylpropionyloxy or 3-Phenylpropenoyloxy Side Chain

Seven new triphenylene discogens with a phenylpropionyloxy or 3-phenylpropenoyloxy side chain, C₁₈H₆(OC_nH_2n＋1)₅OC(O)R' R'＝C≡CC₆H₅, n＝4～9 (1a～1f); R'＝CH＝CHC₆H₅, n＝6 (1g)], were synthesized. Their structures were characterized by ¹H NMR, IR spectra and elemental analy-sis. Their mesomorphism was investigated with differential scanning calorimetry and polarizing optical mi-croscopy. The result showed that all these triphenylene derivatives exhibited enantiotropic hexagonal co-lumnar mesophases. DSC investigations showed that the clearing points of the triphenylenes containing phenylpropionyloxy 1a～1f gradually decreased with n from 4 to 9. The compound 1g containing phenylpropenoyloxy has almost the same clear point with, but lower melting point and crystallization point and wider columnar mesophase range than its counterpart compound 1c.