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Investigating the self‐sorting behaviour of assemblies with subtle structural differences is a captivating yet challenging endeavour. Herein, we elucidate the unusual self‐sorting behaviour of metallacages with subtle structural differences in batch reactors and microdroplets. Narcissistic self‐sorting of metallacages has been observed for two ligands with identical sizes, shapes, and symmetries, with only minor differences in the substituted groups. In particular, the self‐sorting process in microdroplets occurs within 1 min at room temperature, in stark contrast to batch reactors, which require equilibration for 30 min. To reveal the mechanism of self‐sorting and the role of microdroplets, we conducted a series of experiments and theoretical calculations, including competitive self‐assembly, cage‐to‐cage transformation, control experiments involving model metallacages with larger cavities, noncovalent interaction analysis, and root mean square deviation (RMSD) analysis. This research demonstrates an unusual case of self‐sorting of very similar assemblies and provides a new strategy for facilitating the self‐sorting efficiency of supramolecular systems. [ABSTRACT FROM AUTHOR]

Polyradical cages are of great interest because they show very fascinating physical and chemical properties, but many challenges remain, especially for their synthesis and characterization. Herein, we present the synthesis of a polyradical cation cage 14⋅+ through post‐synthetic oxidation of a redox‐active phenothiazine‐based Pd2L4‐type coordination cage 1. It′s worth noting that 1 exhibits excellent reversible electrochemical and chemical redox activity due to the introduction of a bulky 3,5‐di‐tert‐butyl‐4‐methoxyphenyl substituent. The generation of 14⋅+ through reversible electrochemical oxidation is investigated by in situ UV/Vis‐NIR and EPR spectroelectrochemistry. Meanwhile, chemical oxidation of 1 can also produce 14⋅+ which can be reversibly reduced back to the original cage 1, and the process is monitored by EPR and NMR spectroscopies. Eventually, we succeed in the isolation and single crystal X‐ray diffraction analysis of 14⋅+, whose electronic structure and conformation are distinct to original 1. The magnetic susceptibility measurements indicate the predominantly antiferromagnetic interactions between the four phenothiazine radical cations in 14⋅+. We believe that our study including the facile synthesis methodology and in situ spectroelectrochemistry will shed some light on the synthesis and characterization of novel polyradical systems, opening more perspectives for developing functional supramolecular cages. [ABSTRACT FROM AUTHOR]

Room‐temperature sodium‐sulfur (RT Na‐S) batteries are promising for low‐cost and large‐scale energy storage applications. However, these batteries are plagued by safety concerns due to the highly flammable nature of conventional electrolytes. Although non‐flammable electrolytes eliminate the risk of fire, they often result in compromised battery performance due to poor compatibility with sodium metal anode and sulfur cathode. Herein, we develop an additive of tin trifluoromethanesulfonate (Sn(OTf)2) in non‐flammable phosphate electrolytes to improve the cycling stability of RT Na‐S batteries via modulating the Na+ solvation environment and interface chemistry. The additive reduces the Na+ desolvation energy and enhances the electrolyte stability. Moreover, it facilitates the construction of Na‐Sn alloy‐based anode solid electrolyte interphase (SEI) and cathode electrolyte interphase (CEI). These interphases help to suppress the growth of Na dendrites and the dissolution/shuttling of sodium polysulfides (NaPSs), resulting in improved reversible capacity. Specifically, the Na‐S battery with the designed electrolyte boosts the capacity from 322 to 906 mAh g−1 at 0.5 A g−1. This study provides valuable insights for the development of safe and high‐performance electrolytes in RT Na‐S batteries. [ABSTRACT FROM AUTHOR]

Aiming at the construction of novel stimuli‐responsive fluorescent system with precisely tunable emissions, the typical 9,14‐diphenyl‐9,14‐dihydrodibenzo[a, c]phenazine (DPAC) luminogen with attractive vibration‐induced emission (VIE) behavior has been introduced into [2]rotaxane as a stopper. Taking advantage of their unique dual stimuli‐responsiveness towards solvent and anion, the resultant [2]rotaxanes reveal both tunable VIE and switchable circularly polarized luminescence (CPL). Attributed to the formation of mechanical bonds, DPAC‐functionalized [2]rotaxanes display interesting VIE behaviors including white‐light emission upon the addition of viscous solvent, as evaluated in detail by femtosecond transient absorption (TA) spectra. In addition, ascribed to the regulation of chirality information transmission through anion‐induced motions of chiral wheel, the resolved chiral [2]rotaxanes reveal unique switchable CPL upon the addition of anion, leading to significant increase in the dissymmetry factors (glum) values with excellent reversibility. Interestingly, upon doping the chiral [2]rotaxanes in stretchable polymer, the blend films reveal remarkable emission change from white light to light blue with significant 6.5‐fold increase in glum values up to −0.035 under external tensile stresses. This work provides not only a new design strategy for developing molecular systems with fluorescent tunability but also a novel platform for the construction of smart chiral luminescent materials for practical use. [ABSTRACT FROM AUTHOR]

The development of multimode photopatterning systems based on supramolecular coordination complexes (SCCs) is considerably attractive in supramolecular chemistry and materials science, because SCCs can serve as promising platforms for the incorporation of multiple functional building blocks. Herein, we report a light‐responsive liquid‐crystalline metallacycle that is constructed by coordination‐driven self‐assembly. By exploiting its fascinating liquid crystal features, bright emission properties, and facile photocyclization capability, a unique system with spatially‐controlled fluorescence‐resonance energy transfer (FRET) is built through the introduction of a photochromic spiropyran derivative, which led to the realization of the first example of a liquid‐crystalline metallacycle for orthogonal photopatterning in three‐modes, namely holography, fluorescence, and photochromism. [ABSTRACT FROM AUTHOR]

Metallic Na is a promising metal anode for large‐scale energy storage. Nevertheless, unstable solid electrolyte interphase (SEI) and uncontrollable Na dendrite growth lead to disastrous short circuit and poor cycle life. Through phase field and ab initio molecular dynamics simulation, we first predict that the sodium bromide (NaBr) with the lowest Na ion diffusion energy barrier among sodium halogen compounds (NaX, X=F, Cl, Br, I) is the ideal SEI composition to induce the spherical Na deposition for suppressing dendrite growth. Then, 1,2‐dibromobenzene (1,2‐DBB) additive is introduced into the common fluoroethylene carbonate‐based carbonate electrolyte (the corresponding SEI has high mechanical stability) to construct a desirable NaBr‐rich stable SEI layer. When the Na||Na3V2(PO4)3 cell utilizes the electrolyte with 1,2‐DBB additive, an extraordinary capacity retention of 94 % is achieved after 2000 cycles at a high rate of 10 C. This study provides a design philosophy for dendrite‐free Na metal anode and can be expanded to other metal anodes. [ABSTRACT FROM AUTHOR]

This article, published in Angewandte Chemie International Edition, discusses various research articles in the field of chemistry. One article focuses on differentiating chiroptical signals in a topologically chiral [2]catenane using spectroscopy techniques. Another article explores an innovative approach to remediate and upcycle NOx pollutants using organonickel pincer catalysis. A third article presents a method for accessing chiral atropisomers through a dynamic kinetic asymmetric reaction. Additionally, the article mentions research on a new material that functions as a long afterglow emitter and photocatalyst, as well as a method for electrochemically monitoring single vesicle dynamics. [Extracted from the article]

Supramolecular cages/vesicles in biology display sophisticated structures and functions by utilizing a few types of protein subunit quasi‐equivalently at distinct geometrical locations. However, synthetic supramolecular cages still lack comparable complexity to reach the high levels of functionality found in natural systems. Herein we report the self‐assembly of giant pentagonal supramolecular prisms (molecular weight >50 kDa) with tetratopic pyridinyl subunits serving different geometrical roles within the structures, and their packing into a novel superstructure with unexpected three‐fold rotational symmetry in a single two‐dimensional layer of crystalline state. The formation of these complicated structures is controlled by both the predetermined angles of the ligands and the mismatched structural tensions created from the multi‐layered geometry of the building blocks. Such a self‐assembly strategy is extensively used by viruses to increase the volume and complexity of capsids and would provide a new approach to construct highly sophisticated supramolecular architectures. [ABSTRACT FROM AUTHOR]

In this study, we established a feasible strategy to construct a new type of metallo‐polymer with helicoidal structure through the combination of covalent polymerization and intramolecular coordination‐driven self‐assembly. In the design, a tetratopic monomer (M) was prepared with two terminal alkynes in the outer rim for polymerization, and two terpyridines (TPYs) in the inner rim for subsequent folding by selective intramolecular coordination. Then, the linear covalent polymer (P) was synthesized by polymerization of M via Glaser‐Hay homocoupling reaction. Finally, intramolecular coordination interactions between TPYs and Zn(II) folded the backbone of P into a right‐ or left‐handed metallo‐helicoid (H) with double rims. Owing to multiple positive charges on the inner rim of helicoid, double‐stranded DNA molecules (dsDNA) could interact with H through electrostatic interactions. Remarkably, dsDNA allowed exclusive formation of H with right handedness by means of chiral induction. [ABSTRACT FROM AUTHOR]

A recent article in Angewandte Chemie International Edition discusses a new system for photopatterning using a light-responsive liquid-crystalline metallacycle. This system allows for holographic, fluorescent, and photochromic patterning, which has potential applications in optical storage devices for information storage, encryption, and anticounterfeiting. The authors of the article, Haiyan Peng, Lin Xu, and others, explain the concept and its implications in their research. [Extracted from the article]

Inside Back Cover: Highly Efficient Self-Assembly of Metallacages and Their Supramolecular Catalysis Behaviors in Microdroplets (Angew. Confined Space, Metallacages, Microdroplets, Self-Assembly, Supramolecular Catalysis Keywords: Confined Space; Metallacages; Microdroplets; Self-Assembly; Supramolecular Catalysis EN Confined Space Metallacages Microdroplets Self-Assembly Supramolecular Catalysis 1 1 1 06/30/23 20230703 NES 230703 B A highly efficient strategy b for the supramolecular self-assembly of well-defined metallacages in microdroplets through continuous-flow microfluidic devices is described by Lin Xu and co-workers in their Research Article (e202301900). [Extracted from the article]

The bottom‐up synthesis of discrete tubular molecules that mimic the structural features of carbon nanotubes has been a long‐standing pursuit for synthetic chemists. As the shortest segments of armchair‐type carbon nanotubes, cycloparaphenylenes are regarded as ideal macrocyclic building blocks for achieving this goal. Here we report the synthesis of a helical tubular molecule featuring three diyne linkers between two site‐specifically functionalized [9]cycloparaphenylenes. Its C3‐symmetrical, radially conjugated structure and solid‐state packing have been elucidated by spectroscopic and crystallographic characterizations. Notably, the resolved enantiomers display a circularly polarized luminescence brightness value of 1.47×103 M−1 cm−1, which is among the highest values for chiral organic molecules. Furthermore, the diyne‐linked molecule could be directly converted into a thiophene‐linked helical molecule, demonstrating the post‐functionalization approach for the construction of chiral tubular molecules from cycloparaphenylenes. [ABSTRACT FROM AUTHOR]

Starting from AIEgen‐functionalized chiral [2]rotaxane building block, we have successfully synthesized a new class of chiral rotaxane‐branched dendrimers through controllable divergent strategy for the first time, based on which novel chiral artificial light‐harvesting systems (LHSs) were successfully constructed in aqueous phase by sequentially introducing achiral donor and acceptor. More importantly, accompanied by the two‐step Förster resonance energy transfer (FRET) process in the resultant artificial LHSs, the sequentially amplified circularly polarized luminescence (CPL) performances were achieved, highlighting that the chiral rotaxane‐branched dendrimers could serve as excellent relay for both energy transfer and chirality transmission. Impressively, compared with the sole chiral rotaxane‐branched dendrimers, the dissymmetry factors (glum) values of the resultant artificial LHSs were amplified by one order of magnitude up to 0.038, enabling their further applications in information storage and encryption. The proof‐of concept study provides not only a feasible approach for the efficient amplification of CPL performances but also a novel platform for the construction of novel chiral luminescent materials. [ABSTRACT FROM AUTHOR]

π‐Conjugated chiral shape‐persistent molecular nanocarbons hold great potential as chiroptical materials, though their synthesis remains a considerable challenge. Here, we present a simple approach using Suzuki coupling of a [5]helicene building block with various aromatic units, enabling the one‐pot synthesis of a series of chiral macrocycles with persistent figure‐eight and Möbius shapes. Single‐crystal structures of 7 compounds were solved, and 22 enantiomers were separated by preparative chiral HPLC. A notable pyrene‐bridged figure‐eight macrocycle, with its rigid, fully π‐conjugated and overcrowded structure, exhibited pure excimer emission and outstanding circularly polarized luminescence (CPL) properties, including a large dissymmetric factor (|glum|=3.8×10−2) and significant CPL brightness (BCPL=710.5 M−1cm−1). This method provides a versatile synthetic platform for producing various chiral D2‐symmetric figure‐eight macrocycles and singly or triply twisted Möbius macrocycles with C2 and D3 symmetry, offering tunable chiroptical properties for CPL applications. [ABSTRACT FROM AUTHOR]

Aiming at the fabrication of circularly polarized organic light‐emitting diodes (CP‐OLEDs) with high dissymmetry factors (gEL) and color purity through the employment of novel chiral source, topologically chiral [2]catenanes were first utilized as the key chiral skeleton to construct novel multi‐resonance thermally activated delayed fluorescence (MR‐TADF) emitters. Impressively, the efficient chirality induction and unique switchable feature of topologically chiral [2]catenane not only lead to a high |gPL| value up to 1.6×10−2 but also facilitate in situ dynamic switching of the full‐width at half‐maximum (FWHM) and circularly polarized luminescence (CPL). Furthermore, the solution‐processed CP‐OLEDs based on the resultant topologically chiral emitters exhibit a narrow FWHM of 36 nm, maximum external quantum efficiency of 17.6 %, and CPEL with |gEL| of 2.1×10−3. This study demonstrates the successful construction of the first CP‐MR‐TADF emitters based on topological chirality with the highest |gPL| among the reported CP‐MR‐TADF emitters and excellent device performance to the best of our knowledge. Moreover, it endowed the MR‐TADF emitter with distinctive switchable CPL performances, thus providing a novel design strategy as well as a promising platform for developing intelligent CP‐OLEDs. [ABSTRACT FROM AUTHOR]

Near‐infrared (NIR) circularly polarized absorbing or emitting materials offer distinct advantages over their visible‐light counterparts and have attracted considerable interest across various fields. Materials exhibiting NIR chiroptical properties with high fluorescence quantum yields (ΦF) are particularly rare. In this study, we report the synthesis of a series of helical nanographenes (1, 2, 3, and 4), where perylene is fused with one to four hexa‐peri‐hexabenzocoronene (sub) units by a strategy involving Diels–Alder cycloaddition followed by a Scholl reaction. X‐ray crystallographic analysis confirmed their structures, revealing helicene moieties integrated into a highly contorted framework. Benefiting from a similar distribution pattern of frontier molecular orbitals to perylene and extended π‐conjugation, compounds 1–4 demonstrate respectable ΦF values of 31.9 %, 15.0 %, 13.7 %, and 6.5 %, respectively, with emission maxima reaching up to 1010 nm. Their enantiopure forms, isolated by preparative chiral HPLC, exhibit distinct circular dichroism signals and circularly polarized luminescence across a broad spectral range, extending from the ultraviolet to the NIR. [ABSTRACT FROM AUTHOR]

As a novel type of macrocycles with attractive planar chirality, pillar[5]arenes have gained increasing research interest over the past decades, enabling their widespread applications in diverse fields such as porous materials, molecular machines, and chiral luminescence materials. However, the catalytic methodology towards the enantioselective synthesis of planar chiral pillar[5]arenes remains elusive. Here we report a novel method for the enantioselective synthesis of planar chiral pillar[5]arenes via asymmetric Sonogashira coupling, giving access to a wide range of highly functionalized planar chiral pillar[5]arenes, including both homo‐ and hetero‐rimmed ones, with excellent enantioselectivities. Attractively, the resultant planar chiral pillar[5]arenes show great potential for widespread use in many areas such as chiral luminescent materials. This work not only enables the successful synthesis of planar chiral pillar[5]arenes with abundant structural and functional diversity as key building blocks for practical applications but also enriches the asymmetric cross‐coupling methodologies in organic synthetic chemistry. [ABSTRACT FROM AUTHOR]

The exploration of novel functionalized supramolecular coordination complexes (SCCs) can enable new applications in domains that include purification and sensing. In this study, employing a coordination‐driven self‐assembly strategy, we designed and prepared a series of benzochalcogenodiazole‐based metallohelicates as high‐efficiency charge‐transfer surface‐enhanced Raman scattering (SERS) substrates, expanding the range of applications for these metallohelicates. Through structural modifications, including the substitution of single heteroatoms on ligands, replacement of coordinating metals, and alteration of ligand framework linkages, the Raman performance of these metallohelicates as substrates were systematically optimized. Notably, the SERS enhancement factors (EFs) of the metallohelicate‐based SERS substrates were significantly enhanced to levels as high as 1.03×107, which rivals the EFs of noble metals devoid of “hot spots”. Additionally, the underlying Raman enhancement mechanisms of these metallohelicates have been investigated through a combination of control experiments and theoretical calculations. This study not only demonstrates the utility of metallohelicates as SERS substrates but also offers insights and materials for the development of high‐efficiency new charge‐transfer SERS substrates. [ABSTRACT FROM AUTHOR]

Aiming at the further extension of the application scope of traditional molecular muscles, a novel bispyrene‐functionalized chiral molecular [c2]daisy chain was designed and synthesized. Taking advantage of the unique dimeric interlocked structure of molecular [c2]daisy chain, the resultant chiral molecular muscle emits strong circularly polarized luminescence (CPL) attributed to the pyrene excimer with a high dissymmetry factor (glum) value of 0.010. More importantly, along with the solvent‐ or anion‐ induced motions of the chiral molecular muscle, the precise regulation of the pyrene stacking within its skeleton results in the switching towards either “inversed” state with sign inversion and larger glum values or “down” state with maintained handedness and smaller glum values, making it a novel multistate CPL switch. As the first example of chiral molecular muscle‐based CPL switch, this proof‐of‐concept study not only successfully widens the application scopes of molecular muscles, but also provides a promising platform for the construction of novel smart chiral luminescent materials for practical applications. [ABSTRACT FROM AUTHOR]