Characterization of New H-Bonded Liquid Crystalline Complexes Based on Iminophenyl Nicotinate (original) (raw)
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Supramolecular liquid crystals in binary and ternary systems
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Angewandte Chemie International Edition, 2004
There are numerous examples in nature that demonstrate the crucial role of hydrogen bonds. Through imitation of this phenomenon, hydrogen bonds have been used to good effect by researchers to achieve specific synthetic targets. [1] Fields such as supramolecular chemistry and materials science are indebted to this strategy, and important breakthroughs have been achieved by exploiting these inter-or intramolecular "strong and directional, and… lovely" interactions. Liquid crystals, which are related to both of the aforementioned fields, are another example of the attractive possibilities of this interaction. Mesomorphic properties result from a suitable combination of the shape of a molecule and the magnitude and direction of interactions between the molecules. Hydrogen bonding, through self-assembly, has been used to order thermotropic and lyotropic liquid crystals in which the magnitude and the direction of the interactions have been appropriate to maintain order within the fluid state. Calamitic and columnar mesophases of low or high molecular-weight materials have been stabilized with this approach. Such systems have also been obtained by the use of either mesogenic or non-liquid-crystalline moieties.