New troponoid liquid crystals (1–4) with a bitropone core were prepared. The ester derivatives (1) had enantiotropic smectic A and/or C phases with higher thermal stabilities than the corresponding benzenoid derivatives (5), which had a smectic B phase. The amide derivatives (3) had an enantiotropic smectic A phase, but the ether (2) and alkylamine (4) derivatives were not mesomorphic. The crystals of 1c had a layer structure with an intermolecular π–π interaction between the bitropone cores. X-ray diffraction studies revealed that the layer spacings of the smectic A and C phases of 1i were not very much different.
新型的含有双取酮核心的液晶物质(1–4)被制备出来。酯衍
生物(1)具有比相应苯基衍
生物(5)更高的热稳定性,并且具有等温性的向列A相和/或C相,而苯基衍
生物(5)则具有向列B相。胺衍
生物(3)具有等温性的向列A相,但醚(2)和烷基胺(4)衍
生物则没有表现出液晶性。1c的晶体具有层状结构,双取酮核心之间存在分子间的π–π相互作用。X射线衍射研究表明,1i的向列A和C相的层间距并没有太大差异。