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The development of stimuli‐responsive fluorescent materials in water based on organic molecule has drawn significant interest. Herein, we designed and synthesized an amphiphilic molecule M containing a fixed tetraphenylethylene moiety (FTPE) as hydrophobic part and tri(ethylene glycol) (TEG) chains as hydrophilic part. Notably, the FTPE moiety is aggregation‐induced emission (AIE) active, while the TEG chains are thermo‐responsive. M can self‐assemble into fluorescent nanoparticles (NPs) in water, which showed lower critical solution temperature (LCST) behavior. Moreover, its clouding point can be reversibly tuned upon the concentration variation. Interestingly, the NPs can be acted as a fluorescence thermometer in aqueous media owing to their unique AIE and LCST behaviors. Our work herein not only provides an integration strategy to construct stimuli‐responsive fluorescent materials but also shows great potential in biological applications including bioimaging and biosensors. [ABSTRACT FROM AUTHOR]

Sequential energy transfer widely exists in natural light-harvesting systems (LHSs), which greatly benefits the full use of solar energy. In this work, we report an artificial light-harvesting platform derived from pillar (Wang et al., 2021) [5]arene-directed host-guest nanoparticles (WP5 ⊃ G) in aqueous media. The WP5 ⊃ G assembly can serve as a good donor owing to the excellent fluorescence behavior of G in the aggregated state, guaranteeing a two-step FRET from the WP5 ⊃ G to the relay acceptor eosin Y (ESY) and then to the final acceptor Nile red (NiR) to form a WP5 ⊃ G @ ESY / NiR system with high efficiency. As a consequence of the flexibility of the system, tunable emission including a highly efficient white-light emission can be realized. The WP5 ⊃ G @ ESY / NiR system was further used as a photocatalyst to catalyze dehalogenation reaction in aqueous solution, exhibiting remarkable catalytic activity as compared with the WP5 ⊃ G or ESY / NiR alone. [Display omitted] • A light-harvesting system based on self-assembly was successfully fabricated. • The system contains a stepwise energy transfer process. • The material is color tunable and a bright white-light emission was realized. • The material can be used as a photocatalyst for dehalogenation reaction. • The fabrication and application of the system were totally in an aqueous media. [ABSTRACT FROM AUTHOR]

Cobalt-catalyzed C−H amination of arenes with alkylamines by the assistance of 8-aminoquinoline as auxiliary through sp2 C−H bond functionalization has been achieved. Attractive features of this protocol include the low loading of the cobalt catalyst and the readily available reagents. [ABSTRACT FROM AUTHOR]

Supramolecular complexes, including variouslow-molecular-massstructures and large molecular aggregates that are assembled by reversibleand highly directional noncovalent interactions, have attracted moreand more attention due to their fascinating and unconventional chemicaland physical properties that are different from those of traditionalarchitectures encountered by covalently linked backbones. Supramolecularcomplexes are by nature dynamic architectures considering the reversibilityof noncovalent interactions by which small molecular monomers canassemble into specific architectures that are able to be repeatablyreorganized through the assembly/disassembly processes under certainenvironmental factors such as temperature, concentration, and solventconditions. The construction of supramolecular complexes by orthogonalself-assembly with different types of highly specific, noninterferinginteractions is currently attracting considerable interest since theynot only can dynamically self-assemble, but also can be tuned by variousexternal stimuli through addressing each type of noncovalent interactionseparately. Therefore, these dynamic supramolecular complexes, especiallywith external responsiveness, represent the most outstanding candidatesfor the future development of functional and smart materials, andeven mimic the assembling process of natural systems. [ABSTRACT FROM AUTHOR]

Electron-rich dioxynaphthalene (DNP) group bridged bifunctionalureidopyrimidinone (UPy) derivatives (L1, L2, and L3) were synthesized, which could form small cyclicmonomers, oligomers, or linear supramolecular polymers at certainconcentration in solution, to achieve a highly controllable ring–chainequilibrium self-assembling supramolecular system. The ring–chainequilibrium of these supramolecular monomers constructed by differentlengths of oligo(ethylene oxide) (oligoEO) chain as spacers were investigatedby a combination of techniques, such as 1H NMR, DOSY, single-crystalX-ray diffraction, and viscometry. The experiment results demonstratedthat there exists intramolecular π–π stacking interactionbetween DNP group and intramolecularly dimerized UPy motif in themonomeric cyclic form of these supramolecular monomers, and the strengthof this π–π stacking interaction directly dependson the length of the oligoEO chain. Furthermore, strong intramolecularπ–π stacking interaction was found to promote self-assemblyfavorable for intramolecularly cyclic monomerization, leading to agreat increase of critical polymerization concentration (CPC). Monomer L1awith the shortest length of oligoEO chain is present asan exclusive type of intramolecularly hydrogen-bonded assembly, namelythe cyclic monomers, over a broad concentration range (1.6–500mM) in solution. Single crystal structure of the cyclic monomer L1b, which is an analogue of L1a, was thoroughlystudied. The CPC values of monomer L2and L3with longer oligoEO chain are ca. 70 and 23 mM, respectively. However, L2and L3could perform selective cyclizationover the entire concentration range in solution after threading intothe tetracationic cyclobis(paraquat-p-phenylene)cyclophane(CBPQT4+) driven by host–guest interaction, whichprovides another supramolecular strategy to control ring–chainequilibrium. The combined results may provide new insights into thering–chain equilibrium and offer valuable information on theunderstanding of the correlation between supramolecular assistanceand polymerizability. [ABSTRACT FROM AUTHOR]

Artificial light‐harvesting systems (LHSs) are of growing interest for their potential in energy capture and conversion, but achieving efficient fluorescence in aqueous environments remains challenging. In this study, a novel tetraphenylethylene (TPE) derivative, TPEN, is synthesized and co‐assembled with poly(sodium 4‐styrenesulfonate) (PSS) to enhance its fluorescence via electrostatic interactions. The resulting PSS⊃TPEN network significantly increased blue emission, which is further harnessed by an energy‐matched dye, 4,7‐di(2‐thienyl)benzo[2,1,3]thiadiazole (DBT), to produce an efficient LHS with yellow emission. Moreover, this system is successfully applied to develop color‐tunable light‐emitting diode (LED) devices. The findings demonstrate a cost‐effective and environmentally friendly approach to designing tunable luminescent materials, with promising potential for future advancements in energy‐efficient lighting technologies. [ABSTRACT FROM AUTHOR]

The integration of multiple functions within a single fluorescent molecule provides a promising platform for developing versatile, efficient, and cost-effective materials with enhanced performance across diverse applications. In this study, we introduce TPEC, an aggregation-induced emission (AIE) molecule derived from tetraphenylethylene-based tetracarboxylate, which demonstrates multifunctional capabilities, including metal ion sensing and self-erasable writing. TPEC exhibits amphiphilicity in water, self-assembling into single-layer nanosheets with robust blue fluorescence. Notably, the aqueous solution of TPEC displays a fluorescence colorimetric response to Al3+ ions and fluorescence quenching in the presence of Fe³⁺ ions. Additionally, TPEC powders undergo fluorescence colorimetric changes under mechanical stimulation, enabling self-erasable writing on prepared paper. This study presents a straightforward strategy for the development of multifunctional luminescent materials based on the self-assembly of a single-component fluorophore., (© 2024 Wiley‐VCH GmbH.)

Responsive fluorescent nanomaterials have been received considerable attention in recent years. In this work, a bola-type amphiphilic molecule, CSO, was synthesized which contains a hydrophobic cyanostilbene core and hydrophilic oligo(ethylene glycol) (OEG) coils at both sides. The cyanostilbene group is aggregation-induced emission (AIE) active, while the OEG coils are thermo-responsive. As a result, the CSO molecules can self-assemble into blue-fluorescent nanoassemblies with lower critical solution temperature (LCST) behavior in aqueous media. It is noteworthy that the LCST behavior can be reversibly regulated with changes in concentration and the introduction of K + . Intriguingly, fluorescence of CSO assembly shows a blue-shift upon heating. Finally, by employing CSO as a light capturing antenna and energy donor, an artificial light harvesting system with tunable emission and thermo-responsive characteristics was fabricated. This study not only demonstrates an integrated approach to create responsive fluorescent nanomaterials, but also shows great potential for producing luminescent materials and mimicking photosynthesis in nature., (© 2022 Wiley-VCH GmbH.)