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The photophysical and chiroptical properties of a chiral biquinoline amphiphile were found to be closely related to its aggregate states. Photochromism through photo-induced radical and circularly polarized luminescence were realized in its gel state and thin film state, respectively. [ABSTRACT FROM AUTHOR]

To control the dimension of the supramolecular system was of great significance. We construct a two component self-assembly system, in which the gelator LHC18 and achiral azobenzene carboxylic acid could co-assembly and form gels. By modulating the stoichiometric ratio of the two components, not only the morphology could be transformed from 1D nanaotube to 0D nanospheres but also the supramolecualr chirality could be tuned. This work could provide some insights to the control of dimension and the supramolecular chirality in the two-component systems by simply modulating the stoichiometric ratio. [ABSTRACT FROM AUTHOR]

The chiral exciton couplings within a Y-shaped amphiphilic glutamide–cyanostilbene (GCS) could be significantly biased by solvent polarity and hydration effects, which led to sign inversion of both the circular dichroism and circularly polarized luminescence of the GCS assemblies. [ABSTRACT FROM AUTHOR]

Different from molecular level topology, the development of supramolecular topology has been limited due to a lack of reliable synthetic methods. Here we describe a supramolecular strategy of accessing Möbius strip, a fascinating topological object featured with only a single edge and single side. Through bending and cyclization of twisted nanofibers self-assembled from chiral glutamate amphiphiles, supramolecular nano-toroids with various twist numbers were obtained. Electron microscopic techniques could clearly identify the formation of Möbius strips when twist numbers on the toroidal fibers are odd ones. Spectroscopic and morphological analysis indicates that the helicity of the Möbius strips and nano-toroids stems from the molecular chirality of glutamate molecules. Therefore, M- and P-helical Möbius strips could be formed from L- and D-amphiphiles, respectively. Our experimental results and theoretical simulations may advance the prospect of creating chiral topologically complex structures via supramolecular approach. Different to exploring molecular topology, the development of supramolecular topology has been limited due to a lack of reliable synthetic methods. Here, the authors describe a supramolecular strategy to access Möbius strips through bending and cyclization of twisted nanofibers self-assembled from chiral glutamate amphiphiles. [ABSTRACT FROM AUTHOR]

A cyanostilbene conjugated gelator was incorporated into the cavities of cyclodextrins via the host–guest interaction and the resulting supra-gelator from γ-CyD enabled chiroptical photo-switching, while the other gels showed enhanced circularly polarized luminescences. [ABSTRACT FROM AUTHOR]

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Multiple noncovalent interactions can drive self‐assembly through different pathways. Here, by coordination‐assisted changes in π‐stacking modes between chromophores in pyrene‐conjugated histidine (PyHis), a self‐assembly system with reversible and inversed switching of supramolecular chirality, as well as circularly polarized luminescence (CPL) is described. It was found that l‐PyHis self‐assembled into nanofibers showing P‐chirality and right‐handed CPL. Upon ZnII coordination, the nanofibers changed into nanospheres with M‐chirality, as well as left‐handed CPL. The process is reversible and the M‐chirality can change to P‐chirality by removing the ZnII ions. Experimental and theoretical models unequivocally revealed that the cooperation of metal coordination and π‐stacking modes are responsible the reversible switching of supramolecular chirality. This work not only provides insight into how multiple noncovalent interactions regulate self‐assembly pathways. Chirality switch: By efficiently switching the π‐stacking modes, T‐shaped and π–π stacking, of pyrenes by zinc coordination, a dynamic supramolecular system is obtained. The system allows control in the change of circularly polarized luminescence (CPL) and is reversible. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

By constructing a supramolecular light‐harvesting chiral nanotube in the aqueous phase, we demonstrate a cooperative energy and chirality transfer. It was found that a cyanostilbene‐appended glutamate compound (CG) self‐assembled into helical nanotubes exhibiting both supramolecular chirality and circularly polarized luminescence (CPL). When two achiral acceptors, ThT and AO, with different energy bands were co‐assembled with the nanotube, the CG nanotube could transfer its chirality to both of the acceptors. The excitation energy could be transferred to ThT but only be sequentially transferred to AO. During this process, the CPL ascribed to the acceptor could be sequentially amplified. This work provides a new insight into the understanding the cooperative chirality and energy transfer in a chiral supramolecular system, which is similar to the natural light‐harvesting antennas. On the other hand: When the achiral acceptors thioflavin T (ThT) and acridine orange (AO), with different energy bands, were co‐assembled with the nanotube CG it could transfer its chirality to both of the acceptors to give an enhancement of acceptor circularly polarized luminescence (CPL). The excitation energy could be transferred to ThT but only be sequentially transferred to AO. [ABSTRACT FROM AUTHOR]

A naphthalene substituted histidine derivative was found to form an organogel showing circularly polarized luminescence (CPL) and the addition of non-fluorescent achiral benzoic acids could efficiently enhance the CPL via non-covalent interactions. [ABSTRACT FROM AUTHOR]