Extended-Core Discotic Liquid Crystals Based on the Intramolecular H-Bonding in<i>N</i>-Acylated 2,2′-Bipyridine-3,3′-diamine Moieties
作者:Anja R. A. Palmans、Jozef A. J. M. Vekemans、Hartmut Fischer、Rifat A. Hikmet、E. W. Meijer
DOI:10.1002/chem.19970030220
日期:1997.2
new type of disc-shaped molecule (1 a-c) has been synthesised and characterised. The molecules were built up by linking three lipophilic, N-monoacylated 2,2'-bipyridine-3,3'-diamine wedges to a central 1,3,5-benzenetricarbonyl unit. They show liquid crystalline behaviour, as shown by DSC, polarisation microscopy and X-ray diffraction. In all cases the mesophase was characterised as a Dho phase. From
一种新型的盘状分子(1 ac)已经合成并表征。通过将三个亲脂性的N-单酰化的2,2'-联吡啶-3,3'-二胺楔连接到一个中心1,3,5-苯三羰基单元来构建分子。它们显示出液晶行为,如DSC,偏振显微镜和X射线衍射所示。在所有情况下,中间相均被表征为Dho相。从(1)H NMR结果表明,由于强分子内H键,化合物1ac的内部优先采用C3对称构象,从而形成扩展的核。这个大核诱导了分子之间的强相互作用,从而导致中间相增强了热稳定性。