Advances in metal-free heterocycle-based columnar liquid crystals.

Liquid crystals are ordered soft materials formed by self-organized molecules and can potentially be used as new functional materials for electron-, ion- or molecular-transport; optical; and bio-active materials. In particular, the columnar liquid crystals are promising candidates used in various optical and electronic devices. For this purpose, design and synthesis of unconventional materials are essential. In this review, we have summarized several approaches for the synthesis of columnar liquid crystals composed of various heterocyclic systems. We also outline their liquid crystalline and other relevant properties, and their suitability for applications in diverse fields.