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The realization of persistent luminescence and in particular circularly polarized luminescence (CPL) of organic radicals remains a challenge due to their sensitivity to oxygen at ambient conditions and elusive excited state chirality control. Here, it is reported that UV‐irradiation on a supramolecular gel from a chiral triarylamine derivative, TPA‐Ala, led to the formation of luminescent radicals with bright CPL. TPA‐Ala can form an organogel in chloroform with blue emission and supramolecular chirality as demonstrated by both CD and CPL signals. Upon UV 365 nm irradiation, an emission color change from blue to cyan is observed due to the formation of photo‐induced radicals. Interestingly, it is found that the supramolecular gel radicals showed stable luminescence with a lifetime ≈ 10 days in dark environments and inverted CPL, which represents a scarce example with persistent CPL from doublet‐state due to oxygen isolation ability of the gel network. Furthermore, doping a guest dye, Rhodamine B (RhB), into the supramolecular gel (RhB/TPA‐Ala = 30% in molar ratio) successfully obtained a transient white‐light CPL through the superposition of photo‐induced radical and guest dye emissions. This work provides a useful methodology for the fabrication of radical‐based CPL materials via a supramolecular assembly approach. [ABSTRACT FROM AUTHOR]

• Both amphiphiles are capable of forming assemblies and exhibit CD signals. • The supramolecular chirality can be reversed through hydrogen bonding interactions. • The chiral amphiphile assembly is responsive to both acid and metal ions. In this study, we have synthesized two types of Y-shaped chiral amphiphiles, namely L- BG and L- PG , with a benzene or pyridine ring at the terminal position, respectively. The optimized conformations of both amphiphiles indicate the presence of intramolecular interactions. In dimethylformamide (DMF) solution at the monomeric state, both amphiphiles exhibit positive cotton effects; however, in DMF/H 2 O mixed solution, the cotton effects are inverted. Molecular dynamics simulations reveal that both intermolecular and intramolecular hydrogen bonds facilitate the inversion of supramolecular chirality. Additionally, protonation and coordination of L- PG assembly results in chirality inversion and transformation of emission. This study emphasizes the significance of both inter- and intramolecular hydrogen bonds in the assembly process, providing insights into stimuli-responsive chiral supramolecular materials. [Display omitted] [ABSTRACT FROM AUTHOR]

• Both the amphiphiles form assemblies and show obvious CD signals. • The cyano moiety can induce the fluorescent emission transformation. • The existence of cyano moiety lead to the supramolecular chirality inversion in DMSO/H 2 O co-solvents. To modulate both the emission and the chirality in assembly system is important but challenging. Here, we design and synthesize two glutamide based amphiphiles bearing cyanostilbene or stilbene moieties. Both the amphiphiles can self-assemble in DMSO/H 2 O mixed solvent. The existence of cyano group not only induces the fluorescent emission transformation but also leads to supramolecular chirality inversion. Density functional theory and molecular dynamic simulation are conducted and the results reveal that the cyano group has influence on both the charge distribution and the stacking mode. We believe our work will bring some insights into the modulation of supramolecular chirality by precise control of molecular structure. [Display omitted] [ABSTRACT FROM AUTHOR]

We design a cyanostilbene-glutamide-based amphiphile L- GC bearing a long alkyl chain. It can form gels in methanol and exhibit circular dichroism (CD) signals. Upon ultraviolet-light irradiation, the CD signals are inverted and the morphology transforms from fibers to spheres. Chirality and energy transfer can be achieved when L- GC co-assembles with the energy acceptor DBTOC 18. Moreover, the energy-transfer efficiency of the co-assembly can be modulated via photoirradiation-induced isomerization. [Display omitted] • UV irradiation triggers the transformation of CD spectra and nanostructure. • Both chirality and energy transfer can be realized in the co-gel. • Chirality and energy transfer efficiency can be modulated simultaneously. Manipulating chirality and energy transfer simultaneously in a single self-assembly system is important but remains challenging. In this study, we design a cyanostilbene-glutamide-based amphiphile L- GC bearing a long alkyl chain. It can form gels in methanol and exhibit circular dichroism (CD) signals. Upon ultraviolet-light irradiation, the CD signals are inverted and the morphology transforms from fibers to spheres. Chirality and energy transfer can be achieved when L- GC co-assembles with the energy acceptor DBTOC 18 , which is conjugated to a long alkyl chain. Moreover, the energy-transfer efficiency of the co-assembly can be modulated via photoirradiation-induced isomerization. Molecular dynamics simulation was conducted to elucidate the photomodulated assembly behavior. This study realizes the dual modulation of chirality and energy and presents some perspectives for information exchange in chiroptical materials. [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]

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]

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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. [ABSTRACT FROM AUTHOR]

[Display omitted] • Amphiphile forms assembly in acetonitrile and shows circular dichroism signals. • CD signals can be inverted by photo-irradiation. • After UV and heating–cooling process, the minority of E -isomer determined the supramolecular chirality. Here, amphiphile GCH based on glutamide-cyanostilbene is designed and synthesized, it is found that it can assembly in acetonitrile, and shows circular dichroism signals. After Z-E isomerizaition by UV irradiation, the CD signal of the assembly can be inverted. Unexpectedly, after another heating and cooling process, the circular dichroism signals can be totally inverted even though the E -isomers are in minority. Finally, the molecular dynamics (MD) simulations deeply elucidate the supramolecuar chirality inversion mechanism. This work brings some new insights into the control of chirality inversion, which may provide a perspective for the smart chiroptical materials construction. [ABSTRACT FROM AUTHOR]

We design and synthesize several glutamide azobenzene based amphiphiles bearing different length of alkyl chains. The amphiphiles could form self-assemblies and show CD signals in aqueous solution. As the length of the alkyl chains in the amphiphiles increase, the CD signals of the assemblies could be enhanced. However, the long alkyl chains will conversely restrict the isomerization of the azobenzene group and the corresponding chiroptical property. [Display omitted] • The alkyl chain length have great influence on the gelation property. • Long alkyl chain conversely restrict the light-responsive property of the azobenzene moiety. • Dye adsorption efficiency of the assemblies is dependent on the length of the amphiphiles. Controlling the supramolecular chirality of a self-assembly system by molecular structure design and external stimuli in aqueous solution is significant but challenging. Here, we design and synthesize several glutamide-azobenzene-based amphiphiles with different length alkyl chains. The amphiphiles can form self-assemblies in aqueous solution and show CD signals. As the number of the alkyl chain of amphiphiles increases, the CD signals of the assemblies can be enhanced. However, the long alkyl chains conversely restrict the isomerization of the azobenzene and the corresponding chiroptical property. Moreover, the alkyl length can determine the nanostructure of the assemblies and exert critical influence on the dye adsorption efficiency. This work exhibits some insights into the tunable chiroptical property of the self-assembly by delicate molecular design and external stimuli, and emphasizes the molecular structure can determine the corresponding application. [ABSTRACT FROM AUTHOR]

• Gelator GPCS could form supramolecular gel in DMF/H 2 O co-solvents and exhibit obvious CD signals. • After the protonation of the pyridine ring, the fluorescent emission of the gel was transited from 485 nm to 530 nm. • Chirality can be inverted by the protonation process, dual switch of chirality and switch in one system is realized. Regulating both the helicity and fluorescent emission in a self-assembly system is significant, but it is difficult to realize dual switchimg in a single system. Here, organogelator GPCS based on glutamide pyridine-cyanostilbene is designed and synthesized, and it is found that the gelator can form a gel and show obvious circular dichroism signals. After the protonation of the pyridine moiety, not is only the supramolecular chirality inverted but also the fluorescent emission transtions from 485 nm to 530 nm. This work provides insights into the control of chiroptical inversion and emission transition, and may have potential applications such as in the field of anticounterfeiting. [ABSTRACT FROM AUTHOR]