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Dynamic chemistry utilizing both covalent and noncovalent bonds provides valid protocols in manipulating properties of self‐assemblies and functions. Here we employ dynamic chemistry to realize multiple‐route control over supramolecular chirality up to five states. N‐protected fluorinated phenylalanine in the carboxylate state self‐assembled into achiral nanoparticles ascribed to the amphiphilicity. Protonation promoted one‐dimensional growth into helices with shrunk hydrophilicity, which in the presence of disulfide pyridine undergo chirality inversion promoted by the hydrogen bonding‐directed coassembly. Further interacting with the water‐soluble reductant cleavages the disulfide bond to initiate the rearrangement of coassemblies with a chirality inversion as well. Finally, by tuning the pH environments, aromatic nucleophilic substitution reaction between reduced products and perfluorinated phenylalanine occurs, giving distinct chiral nanoarchitectures with emerged luminescence and circularly polarized luminescence. We thus realized a particular five‐state control by combining dynamic chemistry at one chiral compound, which greatly enriches the toolbox in fabricating responsive chiroptical materials. [ABSTRACT FROM AUTHOR]

Dynamic chemistry utilizing both covalent and noncovalent bonds provides valid protocols in manipulating properties of self‐assemblies and functions. Here we employ dynamic chemistry to realize multiple‐route control over supramolecular chirality up to five states. N‐protected fluorinated phenylalanine in the carboxylate state self‐assembled into achiral nanoparticles ascribed to the amphiphilicity. Protonation promoted one‐dimensional growth into helices with shrunk hydrophilicity, which in the presence of disulfide pyridine undergo chirality inversion promoted by the hydrogen bonding‐directed coassembly. Further interacting with the water‐soluble reductant cleavages the disulfide bond to initiate the rearrangement of coassemblies with a chirality inversion as well. Finally, by tuning the pH environments, aromatic nucleophilic substitution reaction between reduced products and perfluorinated phenylalanine occurs, giving distinct chiral nanoarchitectures with emerged luminescence and circularly polarized luminescence. We thus realized a particular five‐state control by combining dynamic chemistry at one chiral compound, which greatly enriches the toolbox in fabricating responsive chiroptical materials. [ABSTRACT FROM AUTHOR]

Halogen bonding acknowledged as a noteworthy weak interaction, has gained growing recognition in the field of supramolecular chemistry. In this study, we selected structurally rigid diaryliodonium ions (I(III)) with two biaxial σ‐holes as halogen‐bond donors, to bind with three chiral acceptor molecules bearing cholesteryl and naphthalimides with distinct geometries. The abundant carbonyl oxygen atoms in side‐arm substituents function as multiple acceptors for halogen bonding. The self‐aggregation of chiral acceptor molecules demonstrates adaptiveness to solvent media, evidenced by the inversion of the Cotton effect and the morphological evolution from spherical to rod‐like nanoarchitectures in different solvent systems. The distinct geometries of the acceptor molecules conferred various binding modes with I(III). The introduction of I(III) as a halogen‐bond donor regulates the aggregation of the donors, achieving amplification of chiroptical signals and inheriting solvent responsiveness from the self‐aggregated assembly. This study successfully utilized rational structural design and multimodal control strategies to achieve regulation of supramolecular chirality. [ABSTRACT FROM AUTHOR]

Halogen bond has received widespread attention in recent years due to the vast applications in supramolecular chemistry, sensing and crystal engineering. In contrast to the normal halogen bonds, [N−I−N] type halogen bond exhibits enhanced strength and solvent resistance capabilities. It adopts a bonding geometry of the three‐center four‐electron bond, where the nitrogen can be a neutral, positive, or negative species such as pyridine, saccharin, and urotropine moieties. The emerging new type halogen bond has found specific potentials in constructing supramolecular architectures and catalysis. This concept provides a brief summary based on recent developments of [N−I−N] type halogen bonding, reviewing and summarizing its synthesis, structure and application. [ABSTRACT FROM AUTHOR]

Solvents influence the structure, aggregation and folding behaviors of solvatochromic compounds. Ultrasensitive solvent mediated chiroptical response is conducive to the fabrication of molecular platform for sensing and recognition, which however, remains great challenges in conceptual or applicable design. Here we report a cysteine‐based single benzene chromophore system that shows ultrasensitivity to solvents. Compared to the ratiometrically responsive systems, the chiroptical activities could be triggered or inverted depending on the substituents of chiral entities with an ultralow solvent volume fraction (<1 vol %). One drop of dipolar solvents shall significantly induce the emergence or inversion of chiroptical signals in bulky phases. Based on the experimental and computational studies, the ultrasensitivity is contributed to the intimate interplay between solvents and chiral compounds that anchors the specific chiral conformation. It illustrates that structurally simple organic compounds without aggregation or folding behaviors possess pronounced solvatochiroptical properties, which sheds light on the next‐generation of chiroptical sensors and switches. [ABSTRACT FROM AUTHOR]

Atomically precise metal nanoclusters (NCs) emerge as fascinating synthons in self‐assembled materials. The self‐assembly of metal NCs are highly sensitive to the environment because they have an inorganic‐organic hybridized structure and a relatively complicated conformation. Here, it is shown that when confined in crowded colloids, a water‐soluble Ag9‐cored nanocluster (Ag9‐NC) can self‐ assemble into ultra‐long (up to millimeters) and photoluminescent ribbons with high flexibility. The ribbon contains rectangularly organized columns of Ag9‐NCs and can undergo secondary self‐assembly to form bundled and branched structures. Formation of ribbons is observed in all the tested colloids, including lyotropic liquid crystals and disordered, three‐dimensional network. The high viscosity/elasticity of the crowded colloids weakens gravity‐induced sedimentation of the ribbons, leading to the formation of an interesting class of inorganic‐organic composite materials where the hard Ag‐containing skeleton strengthens the soft matter. The simultaneously occurring symmetry breaking during the self‐assembly of Ag9‐NCs gives uncontrolled supramolecular chirality, which can be tuned through the majority rule and soldier‐and‐sergeant rule by the introduction of chiral seeds. The regulated chirality and the intrinsic photoluminescence of the Ag9‐NCs ribbons impart the composite material circularly polarized luminescence, opening the door for a variety of potential applications. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents (DESs) show particular properties compared to ionic liquids and other traditional organic solvents. Controlled synthesis of chiral materials in DESs is unprecedented due to the complex interplays between DESs and solutes. In this work, all bio‐derived chiral DESs were prepared using choline chloride or cyclodextrin as hydrogen bonding acceptors and natural chiral acids as donors, which performed as chiral matrices for the rational synthesis of chiroptical materials by taking advantage of the efficient chirality transfer between the DESs and solutes. In a very selective manner, building units with molecular pockets could facilitate strong binding affinity towards chiral acid components of DESs disregarding the presence of competitive hydrogen bonding acceptors. Chirality transfer from DESs to nanoassemblies leads to chirality amplification in the presence of minimal amounts of entrapped chiral acids, thanks to the spontaneous symmetry breaking of solutes during aggregation. This work utilizes chiral DESs to control supramolecular chirality, and illustrates the structural basis for the fabrication of DES‐based chiral materials. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents (DESs) show particular properties compared to ionic liquids and other traditional organic solvents. Controlled synthesis of chiral materials in DESs is unprecedented due to the complex interplays between DESs and solutes. In this work, all bio‐derived chiral DESs were prepared using choline chloride or cyclodextrin as hydrogen bonding acceptors and natural chiral acids as donors, which performed as chiral matrices for the rational synthesis of chiroptical materials by taking advantage of the efficient chirality transfer between the DESs and solutes. In a very selective manner, building units with molecular pockets could facilitate strong binding affinity towards chiral acid components of DESs disregarding the presence of competitive hydrogen bonding acceptors. Chirality transfer from DESs to nanoassemblies leads to chirality amplification in the presence of minimal amounts of entrapped chiral acids, thanks to the spontaneous symmetry breaking of solutes during aggregation. This work utilizes chiral DESs to control supramolecular chirality, and illustrates the structural basis for the fabrication of DES‐based chiral materials. [ABSTRACT FROM AUTHOR]

Hematoxylin has a V-shaped chiral geometry, but its potential in chiroptical self-assembled materials is underdeveloped. Herein, three novel V-shaped chiral hematoxylin derivatives were synthesized, and they showed extended skeletons as well as photophysical and chiroptical behaviors. Moreover, their host–guest interactions with C60 were investigated. Our findings could aid in the design and synthesis of novel chiral host molecules from natural products. [ABSTRACT FROM AUTHOR]

Chiral coassembly that noncovalently incorporates distinct species is an efficient approach to constructing functional chiroptical materials with dynamically controlled properties. However, rational and precise manipulation of the coassembly pathway in multiple-component chiral systems containing three or more species remains a great challenge, and the understanding toward the coassembly selectivity is insufficient. To address these issues, in this work, we introduced a coassembly system containing three species that could mutually bind to each other. Model compounds comprising a chiral π-conjugated amino acid (F5), an electron-rich bipyridine derivative (BPE), and an electron-deficient acceptor (TCNB) were chosen. Interplays between F5/TCNB, F5/BPE, and BPE/TCNB indicated complex pathways in ternary mixing. F5/BPE/TCNB mixing selectively prefers F5/BPE combination that excludes TCNB due to protonation of bipyridines from amino acids that hinders the charge transfer and hydrogen bonds between BPE and TCNB. This selectivity allows for an in situ supramolecular substitution process that adding BPE into F5/TCNB complexes could substitute TCNB to generate F5/BPE coassemblies without breaking the gel morphology, which is assigned as [F5/TCNB]* + BPE → [F5/BPE]* + TCNB. This process unveils the selectivity in three-component chiral self-assembly systems that is useful in fabricating advanced responsive chiroptical materials and realizing the modification of luminescence in a top-down protocol. [ABSTRACT FROM AUTHOR]

Point-chiral groups as pendants conjugated to the aromatic luminophore generate weak chiroptical signals without self-assembly, showing the dependence on the flexibility of tethers, which hinders the development of point-chiral molecular materials with chiroptical properties such as the circularly polarized luminescence (CPL). Herein we introduce the molecular chiroptical materials based on the point chirality on a single benzene luminophore scaffold. Substitutes were stepwise conjugated to single benzene luminophores to boost the steric hindrance and tension, whereby the chirality transfer efficiency from point-chiral substituents to luminophores was enhanced. Multiple intramolecular CH−π interactions anchor the whole asymmetric geometry with ultra-high rotation energy barriers and excellent thermostability. Dissymmetry g-factors of circular dichroism and CPL spectra up to 10−3 order of magnitude were realized in solutions, which are comparable to the inherent-chiral luminophores such as helicene and binaphthyl derivatives. The acridine-appended single benzene system shows the emergence of thermally activated delayed fluorescence (TADF), which extends the potentials of the single benzene chiral system in the TADF-based chiroptical devices. [ABSTRACT FROM AUTHOR]

Multiple constituent coassembly is an emerging strategy to manipulate supramolecular chirality and chiroptical properties such as circularly polarized luminescence (CPL). However, the second or third constituent could not be removed from pristine self‐assembly. Here we developed a constitute‐removable chiral coassembly using sublimation that could realize coassembly with tunable supramolecular chirality, luminescence and CPL properties. Octafluoronapthalene (OFN) with small sublimation enthalpy formed coassemblies with perylene‐conjugated peptoids via arene‐perfluoroarene (AP) interaction that induced the emergence of macroscopic chirality and hypsochromic luminescence from yellow to green. Coassembly with OFN accelerated one‐dimensional growth and induced the emergence of macroscopic chirality and CPL. Despite the stability at ambient conditions, vacuum‐treatment triggered fast sublimation of OFN, which behaved as a sacrificial template. Physical removal of OFN retained the helical nanoarchitectures as well as the basic features of Cotton effects and CPL activities. X‐ray diffraction suggested the back‐fill consolidation occurred on the molecular voids by OFN removal that slightly varied the templated molecular arrangements. Sublimation of perfluorinated building units is green and efficient and non‐destructive, which is potentially applicable in constructing template‐directed chiroptical materials and devices. [ABSTRACT FROM AUTHOR]

Multiple constituent coassembly is an emerging strategy to manipulate supramolecular chirality and chiroptical properties such as circularly polarized luminescence (CPL). However, the second or third constituent could not be removed from pristine self‐assembly. Here we developed a constitute‐removable chiral coassembly using sublimation that could realize coassembly with tunable supramolecular chirality, luminescence and CPL properties. Octafluoronapthalene (OFN) with small sublimation enthalpy formed coassemblies with perylene‐conjugated peptoids via arene‐perfluoroarene (AP) interaction that induced the emergence of macroscopic chirality and hypsochromic luminescence from yellow to green. Coassembly with OFN accelerated one‐dimensional growth and induced the emergence of macroscopic chirality and CPL. Despite the stability at ambient conditions, vacuum‐treatment triggered fast sublimation of OFN, which behaved as a sacrificial template. Physical removal of OFN retained the helical nanoarchitectures as well as the basic features of Cotton effects and CPL activities. X‐ray diffraction suggested the back‐fill consolidation occurred on the molecular voids by OFN removal that slightly varied the templated molecular arrangements. Sublimation of perfluorinated building units is green and efficient and non‐destructive, which is potentially applicable in constructing template‐directed chiroptical materials and devices. [ABSTRACT FROM AUTHOR]

Natural amino acids are the most important building blocks in supramolecular chemistry which possess the best biocompatibility in nature. To the best of our knowledge, although hydrogels based on amino acid derivatives have already been studied widely, there is still no report about natural amino acids hydrogels constructed by metal ions induction method. Herein, the self‐assembly behaviors of twelve natural amino acids with eight metal ions were studied systematically. It is surprising that only sodium L‐Phenylalanine can self‐assemble into hydrogel with ZnCl2. Various methods were used to investigate the formation mechanism of hydrogel. The formation of hydrogel is triggered mainly via π‐π stacking and metal‐ligand interactions. Moreover, this green L‐Phenylalanine hydrogel displays acid responsiveness and relatively stability under high temperature, which has great potential applications in many fields. [ABSTRACT FROM AUTHOR]

Folding phenomenon refers to the formation of a specific conformation widely featured by the intramolecular interactions, which broadly exist in biomacromolecules, and are closely related to their structures and functions. A variety of oligomeric folded molecules have been designed and synthesized, namely "foldamer", exhibiting potentials in pharmaceutical and catalysis. Molecular folding is a promising strategy to transfer chirality from substituents to the whole skeleton, when chirality transfer, amplification, evolution, and other behaviors could be achieved. Investigating chirality using foldamer model deepens the understanding of the structure‐function correlation in biomacromolecules and expands the molecular toolbox towards chiroptical and asymmetrical chemistry. Substitutes with abundant hydrogen bonding sites conjugated to a rotatable aryl group afford a parallel β‐sheet‐like conformation, which enables the emergence and manipulation of axial chirality. This concept aims to give a brief introduction and summary of the hydrogen bonded foldamers with anchored axial chirality, by taking some recent cases as examples. Design principles, control over axial chirality and applications are also reviewed. [ABSTRACT FROM AUTHOR]

Hydrogels behave as potential candidates to investigate circularly polarized light (CP)‐matter interaction, which however suffer from small sensitivity towards circular polarization. Here we report a general protocol to build hydrogels from π‐conjugated amino acids with coassembled charge‐transfer (CT) complexes, covering a wide scope of donors and acceptors, which were incorporated into stable hydrogel matrices. CT complexes formed block coassemblies with gelators, induced the emergence of macroscopic chiral helices, where efficient chirality transfer occurs to realize tunable Cotton effects from visible light to NIR‐I region depending on the structures of CT pairs. The hybrid hydrogels showed tunable photothermal performances with excellent heating‐cooling cycling durability. Circularly polarized NIR light selectively triggered gel‐solution phase transition at different timescales. Left‐ and right‐CP illumination generates up to 2.5 folds difference in gel collapse time that allows for direct discrimination by naked eyes. [ABSTRACT FROM AUTHOR]

Hydrogels behave as potential candidates to investigate circularly polarized light (CP)‐matter interaction, which however suffer from small sensitivity towards circular polarization. Here we report a general protocol to build hydrogels from π‐conjugated amino acids with coassembled charge‐transfer (CT) complexes, covering a wide scope of donors and acceptors, which were incorporated into stable hydrogel matrices. CT complexes formed block coassemblies with gelators, induced the emergence of macroscopic chiral helices, where efficient chirality transfer occurs to realize tunable Cotton effects from visible light to NIR‐I region depending on the structures of CT pairs. The hybrid hydrogels showed tunable photothermal performances with excellent heating‐cooling cycling durability. Circularly polarized NIR light selectively triggered gel‐solution phase transition at different timescales. Left‐ and right‐CP illumination generates up to 2.5 folds difference in gel collapse time that allows for direct discrimination by naked eyes. [ABSTRACT FROM AUTHOR]

Chirality transfer from chiral molecules to assemblies is of vital importance to the design of functional chiral materials. In this work, selective co‐assembly behaviors between chiral molecules and an achiral luminophore, potentially driven by the intermolecular salt‐bridge type hydrogen bonds are reported. Cyano‐substituted tetrakis(arylthio)benzene carboxylic acid (TA) served as the luminophore and hydrogen bond donors, which underwent co‐assembly with different chiral amines. It was found that structures of chiral amines affect the chirality transfer and the properties of co‐assemblies due to effects on hydrogen bonds and stacking pattern. Only in specific co‐assemblies, the chiroptical properties occurred at both ground state and excited states based on the emerged Cotton effects and circularly polarized luminescence (CPL) signals, revealing that the chirality was successfully transferred from molecular level to supramolecular level. In addition, accurate quantitative examination of chiral amines was realized by circular dichroism (CD) spectra. This work demonstrates the characteristic chirality response and transfer through co‐assembly, providing a potential method to develop smart chiroptical materials. [ABSTRACT FROM AUTHOR]

The incorporation of platinum(II) metallacycles into supramolecular chiral arrays has potential in introducing intriguing chiroptical activities and applications; however, it remains a considerable challenge due to their shape-persistent feature. Herein, we present the noncovalent modulation of supramolecular chirality in platinum(II) metallacycle-involved host–guest complexation. Tetraphenylethylene-based platinum(II) metallacycles were designed and synthesized, which exhibited aggregation-induced emission with fine-tailored luminescence colors. A hex-armed tyrosine derivative showed size matching towards the metallacycles. Driven by multiple electrostatic attractions, highly affinitive host–guest complexation occurred with 1 : 1 binding stoichiometry and a constant with a 108 order of magnitude. Host–guest complexation turned on the fluorescence of the metallacycles, which also appended chirality to the photoexcited state. Circularly polarized luminescence at different wavelengths was observed, benefiting from the robust complexation, realizing the noncovalent modulation of chirality to the platinum(II) metallacycles. This work establishes a strategy to transfer chirality via host–guest interaction to shape-persistent metallacycles with potential chiroptical applications. [ABSTRACT FROM AUTHOR]

Using green chemistry to control chirality at hierarchical levels as well as chiroptical activities endows with new opportunities to the development of multiple functions. Here, the four‐component Ugi reaction is introduced for the general and precise optical chirality sensing of amines as well as the surface nanoengineering of chiral soft self‐assemblies. To overcome the relatively weak Cotton effects, direct synthesis of a folded peptide structure on a rotatable ferrocene core with axial chirality was accomplished from chiral amine, 1,1'‐ferrocenyl dicarboxylic acid, formaldehyde and isocyanide. Enhanced Cotton effects benefiting from the folded structure allow for the precise and quantitative sensing of natural and synthetic chiral amines covering alkyl, aromatic amines and amino acid derivatives. In addition, aqueous reaction enables the modification of amine‐bearing dye to microfibers self‐assembled from π‐conjugated amino acids. Surface dye‐modification via Ugi reaction barely changes the pristine morphology, showing non‐invasive properties in contrast to dye staining, which is applicable in soft nano/microarchitectures from self‐assembly. This work which combines the four‐component Ugi reaction to enable precise ee% detection and surface nanoengineering of soft chiral assemblies sheds light on the advanced application of green chemistry to chirality science. [ABSTRACT FROM AUTHOR]

The halogen bond is the attractive interaction between the electrophilic region of a halogen atom and the nucleophilic region of another molecular entity, emerging as a favorable manner to manipulate supramolecular chirality in self‐assemblies. Engineering halogen bonded helical structures remains a challenge due to its sensitivity to solvent polarity and competitive forces like hydrogen bonds. Herein, we report a X⋅⋅⋅X (X=Cl, Br, I) type weak halogen bond that induces the formation and evolution of supramolecular helical structures both in solid and solution state. The π‐conjugated phenylalanine derivatives with F, Cl, Br and I substitution self‐assembled into 21 helical packing driven by hydrogen bond and halogen bond, respectively. The specific molecular geometries of π‐conjugated amino acids gave rise to multiple noncovalent forces to stabilize the X⋅⋅⋅X halogen bond with small bond energies ranging from −0.69 to −1.49 kcal mol−1. Halogen bond induced an opposite helicity compared to the fluorinated species, accompanied by the inversed circularly polarized luminescence. [ABSTRACT FROM AUTHOR]

The halogen bond is the attractive interaction between the electrophilic region of a halogen atom and the nucleophilic region of another molecular entity, emerging as a favorable manner to manipulate supramolecular chirality in self‐assemblies. Engineering halogen bonded helical structures remains a challenge due to its sensitivity to solvent polarity and competitive forces like hydrogen bonds. Herein, we report a X⋅⋅⋅X (X=Cl, Br, I) type weak halogen bond that induces the formation and evolution of supramolecular helical structures both in solid and solution state. The π‐conjugated phenylalanine derivatives with F, Cl, Br and I substitution self‐assembled into 21 helical packing driven by hydrogen bond and halogen bond, respectively. The specific molecular geometries of π‐conjugated amino acids gave rise to multiple noncovalent forces to stabilize the X⋅⋅⋅X halogen bond with small bond energies ranging from −0.69 to −1.49 kcal mol−1. Halogen bond induced an opposite helicity compared to the fluorinated species, accompanied by the inversed circularly polarized luminescence. [ABSTRACT FROM AUTHOR]

Circularly polarized luminescence (CPL) active materials have received increasing attention due to their promising applications in fields such as photoelectric devices, spintronic devices and information storage systems. In developing CPL‐active materials, the key issue is to amplify the dissymmetry g‐factor (glum) and flexibly regulate the handedness, luminescence color and other properties. Relying on non‐covalent forces, multicomponent assembly provides an effective solution for control over CPL features. This Minireview summarizes recent progress in the regulation and amplification of CPL‐active materials in multicomponent coassembled systems, where the role of solvents, metal ions, quantum dots, achiral luminophores and nematic liquid crystals as well as a series of photophysical approaches including Förster resonance energy transfer (FRET), charge transfer (CT), arene‐perfluoroarene (AP) interactions and photon upconversion between different components are discussed. Furthermore, future challenges and opportunities of CPL‐active materials in multicomponent assembly systems are also reviewed. This Minireview aims to provide inspiration for the rational design and manufacture of CPL‐active materials based on multicomponent assembly. [ABSTRACT FROM AUTHOR]

Fluorescent chemosensors represent fast response to analytes with pronounced luminescent variations. They are promising as potential candidates in controlling luminescence and chiroptical activities of self-assembled chiral systems, which however have not been accomplished to date. We present a coassembled multiple component system that could respond to SO2 derivatives, giving rise to dynamic aggregation behaviors and switchable luminescence as well as circularly polarized luminescence (CPL). Cholesteryl-naphthalimide and coumarin derivatives coassemble into vesicles and nanohelices under the solvent strategy, behaving as energy transfer donor and accepter respectively. Energy transfer enables CPL transition from green to red depending on the molar fraction. After the addition of SO2 derivatives, hypochromic shifts occur to CPL due to the nucleophilic addition reaction to coumarin domain, hindering energy transfer and allow for the emergence of pristine luminescence. Here, we show a protocol to control over luminescence and chiroptical features of supramolecular chiral self-assemblies using fluorescent chemosensors. 'Fluorescent chemisensors with fast response time and pronounced luminescence variation are important but have not been well investigated for self-assembled chiral systems. Here, the authors present a coassembled multiple component system that responds to SO2 derivatives, giving rise to dynamic aggregation behaviors and switchable luminescence as well as circularly polarized luminescence. [ABSTRACT FROM AUTHOR]

Beyond merely as a solvent, water is increasingly recognized as an active constituent in physiochemical processes of artificial and biological systems. Its mysterious role in controlling the mechanical movement of chiral molecular systems has not been addressed so far. Here, we present unprecedented hydration-driven chiral molecular rotor systems based on the Herrick's conformation of N-terminated ferrocene diamino acids. In solid and solution phases, double intramolecular H-bonds fixed the orientation of amino acids to allow for chirality transfer to ferrocene, which demonstrated significant dependence on solvent environments. Water intercalation aroused the destruction of pristine H-bonds between adjacent amino acids and the formation of new H-bonds, driving the movement of diamino acid arms with increased dihedral angles. Water dynamics in molecular switching behavior were illustrated by proton NMR and DFT calculations that indicated the intercalation of water via multiple H-bonds. Hydration-triggered molecular movement caused pronounced variations to the induced axial chirality with switchable chiroptical responses. This work discloses the crucial role of water in chiral switchable molecular movement behavior, and provides a promising protocol for fabricating external field-responsive chiral materials. [ABSTRACT FROM AUTHOR]

π-Conjugated amino acids are widely applied in chiroptical materials, in which chiroptical activities are believed to originate from supramolecular packing. However, the intramolecular contribution has been largely ignored. In this work, we report that intramolecular chirality transfer behaviors in ferrocene-conjugated amino acids depend on the substituent groups, which influence the modality of multiple intramolecular interactions, as well as the molecular geometry. The structural basis and structure–property relationships of chirality and chiroptical activities were unveiled in this work. Based on single crystal structure and density functional theory calculations, we demonstrate that intramolecular weak forces, including hydrogen bonds, CH⋯π interactions and van der Waals interactions, affect the molecular geometry and contribute to diverse Cotton effects. This work provides evidence for the ignored intramolecular factors in self-assembled systems and paves the way for the fabrication of functional chiroptical systems. [ABSTRACT FROM AUTHOR]

Incorporation of giant molecular nanoparticles with atomic precision into chiral nanoassemblies facilitates the fabrication of functional ordered phases with supramolecular chirality, which remains mysterious. Reported here is the first example of polyhedral oligosilsesquioxane (POSS) derivatives that self‐assemble into well‐defined chiral nanoassemblies. POSSs were covalently conjugated to N‐terminal aromatic amino acids, which self‐assembled into nanohelices and twists with explicit handedness tuned by solvent polarity. Chiral nanoassemblies showed active chiroptical responses including Cotton effects and circularly polarized luminescence. The chiral systems can bind guest molecules by charge‐transfer interactions, whereby self‐assembled structures, chiroptical activities, and luminescent colors were further modulated. The unique coassembly systems were applied for instant information encryption and storage with multiple luminescent displays. This work offers a new protocol for the design of functional chiral materials of POSS by molecular self‐assembly. [ABSTRACT FROM AUTHOR]

Incorporation of giant molecular nanoparticles with atomic precision into chiral nanoassemblies facilitates the fabrication of functional ordered phases with supramolecular chirality, which remains mysterious. Reported here is the first example of polyhedral oligosilsesquioxane (POSS) derivatives that self‐assemble into well‐defined chiral nanoassemblies. POSSs were covalently conjugated to N‐terminal aromatic amino acids, which self‐assembled into nanohelices and twists with explicit handedness tuned by solvent polarity. Chiral nanoassemblies showed active chiroptical responses including Cotton effects and circularly polarized luminescence. The chiral systems can bind guest molecules by charge‐transfer interactions, whereby self‐assembled structures, chiroptical activities, and luminescent colors were further modulated. The unique coassembly systems were applied for instant information encryption and storage with multiple luminescent displays. This work offers a new protocol for the design of functional chiral materials of POSS by molecular self‐assembly. [ABSTRACT FROM AUTHOR]

In this work, we report a highly accurate quantitative ee value detection of chiral acids based on the coassembly between achiral benzimidazole derivatives and chiral acids, wherein the chiral transfer occurred from chiral acids to imidazole probes accompanied by the emergence of Cotton effects. A well-defined linear correlation between gabs and ee values with a correlation coefficient (R2) up to 0.999 was accomplished in such coassembled systems. Except for the linear gabs–ee dependence, both positive and negative nonlinear gabs–ee dependence with high R2 (0.999 and 0.998) were also observed. Therefore, the application for the detection of ee values of natural and synthesized chiral acids can be achieved by relying on the fine linear and nonlinear correlations with gabs. This work provides a simple and generic method to quantitatively determine ee values using novel molecular probes for natural and synthesized chiral acids via a two-component coassembly. [ABSTRACT FROM AUTHOR]

Deep understanding of structure–property relationship between packing of chiral building units and their chiroptical behaviors would significantly facilitate the rational design and fabrication of the emerging chiroptical materials such as circularly polarized luminescence (CPL) emissive materials. In this paper, we unveil the universal existence of supramolecular tilt helical superstructures in self‐assembled π‐conjugated amino acid derivatives. A series of coded amino acid methyl esters were conjugated to anthracene segments at N‐terminus, which afforded 21 and 31 symmetry supramolecular tilt chirality in solid‐states. Helical assemblies enabled diversified Cotton effects and CPL performances, which were in accordance with the tilted chirality between anthracene segments. Such correlation shows fine universality, whereby the chiroptical prediction could be realized. Furthermore, on top of charge‐transfer complexation, manipulation of CPL emission colors and handedness were realized. [ABSTRACT FROM AUTHOR]

Deep understanding of structure–property relationship between packing of chiral building units and their chiroptical behaviors would significantly facilitate the rational design and fabrication of the emerging chiroptical materials such as circularly polarized luminescence (CPL) emissive materials. In this paper, we unveil the universal existence of supramolecular tilt helical superstructures in self‐assembled π‐conjugated amino acid derivatives. A series of coded amino acid methyl esters were conjugated to anthracene segments at N‐terminus, which afforded 21 and 31 symmetry supramolecular tilt chirality in solid‐states. Helical assemblies enabled diversified Cotton effects and CPL performances, which were in accordance with the tilted chirality between anthracene segments. Such correlation shows fine universality, whereby the chiroptical prediction could be realized. Furthermore, on top of charge‐transfer complexation, manipulation of CPL emission colors and handedness were realized. [ABSTRACT FROM AUTHOR]

Many plant tendrils coil into helices which further exhibit terminal-spiral behavior in toroids. In this work, we illustrate the occurrence of such behavior at nano- and microscales whereby nanohelices feature tendril coil-type terminal-cyclization, allowing for the co-existence of toroid-terminated helical superstructures and independent chiral nanotoroids. Multiple-component coassembly was employed to magnify the chirality evolution from the molecular to the macroscopic scale, enabling a consecutively varied supramolecular chirality inversion expressing on Cotton effects, circularly polarized luminescence (CPL) and macroscopic handedness of superstructures. N-Terminal aryl serine derivatives were noncovalently bound to distinct species via charge-transfer and duplex H-bonds, which diminished the unfavorable competitive pathways and facilitated a ternary coassembly route. Hierarchical and modularized coassembly from one to three species witnessed the consecutive chirality inversion, which enabled the flexible chiroptical manipulation including Cotton effects and CPL. Spring-like helices by coassembly demonstrate terminal-spiral behavior, allowing for the formation of heterojunction-like superstructures, which shares a similar process to the tendril coiling. Due to the specific cyclization behavior, the affiliated and independent toroidal structures share identical chirality to helices. Such a ternary coassembly affords a modularized and precise protocol to noncovalently synthesize soft topological structures with fine tailored CPL handedness, dissymmetry factor and luminescent colors. [ABSTRACT FROM AUTHOR]

In the solid state, amino acids (alanine and phenylglycine) with appended pyrene segments self‐assembled into α‐helix‐like structures by asymmetrical H‐bonds between carboxylic acid and amide segments, further inducing supramolecular tilted chirality of the achiral pyrenes. These structures bind melamine and electron‐deficient units through H‐bond and charge‐transfer interactions, respectively. Charge‐transfer interactions enhance the dissymmetry g‐factor of absorption (gabs; up to 1.4×10−2) with an extended Cotton effect active region (from 250 to 600 nm). Incorporating melamine inverts the handedness of circularly polarized luminescence and boosts the dissymmetry g‐factor (glum). Melamine also induces macroscopic chirality at the nanoscale, whereby the 2D lamellar structures are transformed into 1D helices at the nanoscale, leading to giant tubular structures at the microscale. [ABSTRACT FROM AUTHOR]

In the solid state, amino acids (alanine and phenylglycine) with appended pyrene segments self‐assembled into α‐helix‐like structures by asymmetrical H‐bonds between carboxylic acid and amide segments, further inducing supramolecular tilted chirality of the achiral pyrenes. These structures bind melamine and electron‐deficient units through H‐bond and charge‐transfer interactions, respectively. Charge‐transfer interactions enhance the dissymmetry g‐factor of absorption (gabs; up to 1.4×10−2) with an extended Cotton effect active region (from 250 to 600 nm). Incorporating melamine inverts the handedness of circularly polarized luminescence and boosts the dissymmetry g‐factor (glum). Melamine also induces macroscopic chirality at the nanoscale, whereby the 2D lamellar structures are transformed into 1D helices at the nanoscale, leading to giant tubular structures at the microscale. [ABSTRACT FROM AUTHOR]

A rational design of chiroptical active materials from a multi-component co-assembly remains a great challenge due to the spontaneous pathway competition and complexity. In this study, we report a modularized, ternary component co-assembly system constituted by two N-terminated aromatic glutamic amino acids and an imidazole-based binder, which demonstrate mutual binding behaviors via aromatic interactions and complementary H-bonds that allow for flexible manipulation of the chiroptical activities, including circularly polarized light absorbance and luminescence. Through a modular combination, we synthesized up to six self-assembled aggregates with distinct chiroptical activities, showing chirality emergence, transfer, amplification and inversion behaviors. The modular molecular self-assembly protocol provides an alternative route to the noncovalent synthesis of chiroptical active materials with high throughput efficacy. [ABSTRACT FROM AUTHOR]