Laboratory of Organic Chemistry, Eindhoven University of Technology POBox 513, 5600 MB Eindhoven (The Netherlands), Fax: Int. code +(40)245-1036, e-mail:
Chemistry. 1997 Feb;3(2):300-7. doi: 10.1002/chem.19970030220.
A 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 (1) H NMR results it was shown that the interior of compounds 1 a-c preferentially adopts a C3 symmetrical conformation owing to strong intramolecular H-bonding, which gives rise to an extended core. This large core induces strong interactions between molecules, leading to mesophases of enhanced thermal stability.
一种新型盘状分子（1a-c）已经被合成并进行了特征描述。这些分子是通过将三个亲脂性的 N-单酰化 2,2'-联吡啶-3,3'-二胺楔形物连接到一个中心的 1,3,5-苯三甲酰基单元上构建而成的。它们表现出液晶行为，如差示扫描量热法（DSC）、偏光显微镜和 X 射线衍射所示。在所有情况下，中间相都被表征为 Dho 相。从 1 H NMR 结果可以看出，由于强的分子内氢键，化合物 1a-c 的内部优先采用 C3 对称构象，从而形成了一个扩展的核心。这个大的核心诱导分子之间的强烈相互作用，导致中间相具有增强的热稳定性。
