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报道了4-正烷氧基苯甲酸和4-正全氟己基苯甲酸分别与吡啶衍生物3a,3b通过分子间氢键形成的超分子液晶化合物的合成和热致液晶性.目标超分子液晶化合物的介晶性和氢键的缔合通过热台偏光显微镜,差示扫描量热法,核磁和红外光谱进行了研究.结果显示:吡啶衍生物3a,3b不具有液晶性.4-正烷氧基苯甲酸与吡啶衍生物3a,3b形成的复合物4a和4b具有向列相和近晶C相,而4-全氟己基苯甲酸与吡啶衍生物3a,3b形成的复合物6a,6b则呈现多个近晶相.4a-n系列化合物比4b-n系列具有更高的熔点和清亮点,而4b-n系列存在明显的奇偶效应.红外光谱证实了羧基与吡啶基之间存在氢键.
The synthesis and thermotropic liquid crystalline properties of 4-n-alkoxybenzoic acid and 4-n-perfluorohexylbenzoic acid and pyridine derivatives 3a and 3b by intermolecular hydrogen bonding were reported. The target supramolecular liquid crystal The mesomorphicity and hydrogen bond association of the compounds were studied by hot stage polarization microscopy, differential scanning calorimetry, nuclear magnetic resonance and infrared spectroscopy.The results showed that the pyridine derivatives 3a and 3b did not have liquid crystallinity.4- The complexes 4a and 4b of the oxybenzoic acid with the pyridine derivatives 3a, 3b have a nematic phase and a smectic C phase, whereas the complexes 6a, 6b of the 4-perfluorohexylbenzoic acid with the pyridine derivatives 3a, 3b Then there are many smectic phases.4a-n series compounds have higher melting point and clearing point than 4b-n series, while there is obvious odd-even effect on 4b-n series.The infrared spectrum confirms the presence of hydrogen between carboxyl group and pyridyl group key.