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Recently supramolecular chirality has received increasing interest due to its potential applications in enantioselective sensors and chromatographic separation of enantiomers. The appearance of such chirality results from the helical organization of molecules manifested by H-bonding interactions, weak van der Waals forces, and electrostatic forces. In recent years a lot of interest has been focused towards the synthesis of chiral conjugated polymers such as polyacetylene, polythiophene, polypyrrole, polyaniline (PANI), and poly(p-phenylene vinylene) due to their potential applications in circularly polarized electroluminescence and chiral electrode for asymmetric synthesis. Among these chiral PANI is desirable because it is inexpensive, environmentally stable, and can be readily doped and dedoped using simple acid–base stimuli. Besides PANI does not require any synthetic steps before the polymerization of achiral aniline and totally relies on the preferential formation of either right- or left-handed helix of the polymer backbone due to the presence of a chiral dopant in the reaction medium. Different types of chiral acids have been used for the creation of helical polyaniline using different methods. This review paper presents a detailed discussion of different methods of synthesizing helical/chiral polyaniline, different types of dopants used for chirality induction, chirality measurement by circular dichroism spectroscopy, parameters controlling induction and stabilization of chirality in PANI, and application of chiral polyanilines in diverse areas such as enantiomer separation, enantioselective synthesis, chiral nanocomposites, and microwave absorption. [ABSTRACT FROM AUTHOR]

The existence of an object, non-superimposable on its mirror image, constitutes the phenomenon of chirality. This phenomenon is often treated as a curiosity without broader practical consequences. This paper aims to show the significant implications of chirality for chemistry and biology. Chirality is inherent to all living organisms and is essential for their functioning. For instance, biomolecules are composed of chiral building blocks (amino acids, monosaccharides), which are chiral and occur predominantly with one sense of handedness (homochirality of life). The explanation of the evolution of the homochirality of life is therefore one of the important questions connected with the origin of life. The paper also shows why asymmetry with respect to mirror reflection is a general attribute of our world. Historical milestones in the scientific reflection on chirality are also presented, starting with the French crystallographers of the late 18th century, through the work of Pasteur, the fundamentals of organic stereochemistry postulated by van 't Hoff and Le Bel, the elucidation of a structure of monosaccharides by Fischer, and ending with the discovery of the absolute configuration of a molecule and the confirmation of parity violation of weak interaction. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Circularly polarized luminescent (CPL) materials with intense emission and high luminescence dissymmetry factor (glum) are highly desirable for their promising applications in communication technologies, nanotechnologies, innovative materials, etc. Motivated by benefits in supramolecular chemistry and aggregation‐induced emission (AIE) materials for the development of advanced luminescent materials, herein, we report a new class of CPL‐active AIE luminogens (AIEgens) by incorporating the p‐terphenylene (TP) with chiral alkoxyl chains. Aggregation‐induced emission and supramolecular chirality have been realized by hierarchical self‐assembly of these TP cored coil‐rod‐coil molecules under the synergistic effect of π‐π stacking, hydrogen bonding and van der Waals forces. Helical nanofibers with length up to several microns and tunable handedness in different condensed states, such as in poor solvents, thin films and gel states are produced, which exhibit strong CPL signals (glum) of ca. 10–2 and fluorescence quantum yields up to 56.7%. The well‐defined one‐component self‐assembly of AIEgens from a concise molecular design is expected to pave a general avenue to fabricate chiroptical materials with both strong emission and high glum, which would be practically important for advanced modern technologies. [ABSTRACT FROM AUTHOR]