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Regulation of fluorescence and self‐assembly of a salicylaldehyde azine‐containing amphiphile by a water‐soluble pillar[5]arene via host–guest recognition in water was realized. The fluorescence and the self‐assembled aggregates of the bola‐type amphiphile G can be tailored by adding different amounts of water‐soluble pillar[5]arene (WP5). In addition, the emission property and self‐assembly behavior of G and WP5 are responsive to pH conditions. Furthermore, the fluorescence emission property of G and the regulation by WP5 or pH conditions was applied as information encryption material, rewritable paper, and erasable ink. We believe that this fluorescence regulation strategy is promising for the construction of advanced fluorescent organic materials. [ABSTRACT FROM AUTHOR]

A single amino acid in a peptide sequence can play an important role to tune the self‐assembly and hydrogelation behaviour. Here, a C‐terminal cysteine‐containing ultrashort peptide hydrogelator forms hydrogel through non‐covalent and covalent interactions. Interestingly, the hydrogel is insoluble in water and buffer solutions at different pH values (1‐13) and is thixotropic and injectable. In recent years, removing dyes from contaminated water has become a significant concern because of the shortage of freshwater resources. Therefore, the adsorption of dyes through a reliable, straightforward, nontoxic, cheap, and environmentally friendly adsorbent has become a popular topic. Hence, the hydrogelator was exploited to remove organic dyes from wastewater, harnessing its applicability in the gel phase and solid supports (filter paper and cotton). [ABSTRACT FROM AUTHOR]

Supramolecular chemistry has become an interdisciplinary discipline of chemistry, physics, and biology. As a huge subunit of supramolecular compounds, the functional metal–organic supramolecular systems with well‐defined cavities which are able to accommodate size‐suitable guests via benign host‐guest behavior, have been known as "metal–organic molecular containers" (MOMCs) and attracted much attentions for their rich chemical properties and wide potential applications in molecular recognition, catalysis, bio‐medical and other fields. In particular, the MOMCs with flexible backbones exhibit a unique feature both in the aspect of structural construction and applications, due to the free rotation and self‐adaptively of the specific functional groups in the skeletons. In this paper, we review several selected examples of the coordination‐driven metal–organic supramolecular systems from the aspects of self‐assembly construction to the various applications. The self‐assembly strategies, especially the different choice of organic ligands with flexible backbones during the construction, leading to quite diverse configurations compared to the rigid ligands, have been also discussed to show a different perspective of metal–organic system construction. [ABSTRACT FROM AUTHOR]

Recently, resistance random access memories (RRAMs) have been studied extensively, because the demand for information storage is increasing. However, it remains challenging to obtain a flexible device because the active materials involved need to be nontoxic, nonpolluting, distortion‐tolerable, and biodegradable as well adhesive to diverse flexible substrates. In this paper, tannic acid (TA) and an iron ion (FeIII) coordination complex were employed as the active layer in a sandwich‐like (Al/active layer/substrate) device to achieve memory performance. A nontoxic, biocompatible TA‐FeIII coordination complex was synthesized by a one‐step self‐assembly solution method. The retention time of the TA‐FeIII memory performance was up to 15 000 s, the yield up to 53 %. Furthermore, the TA‐FeIII coordination complex can form a high‐quality film and shows stable ternary memory behavior on various flexible substrates, such as polyethylene terephthalate (PET), polyimide (PI), printer paper, and leaf. The device can be degraded by immersing it in vinegar solution. Our work will broaden the application of organic coordination complexes in flexible memory devices with diverse substrates. Flexible memory: Tannic acid (TA) and an iron (FeIII) coordination complex were employed as an active layer in a sandwich‐like (Al/active layer/substrate) device to achieve memory performance. A nontoxic, biocompatible TA‐FeIII coordination complex was synthesized by a one‐step self‐assembly solution method. This complex can form a film on various flexible substrates (PET, PI, paper, and leaf) and all display ternary memory performance (see graphic). [ABSTRACT FROM AUTHOR]

The construction of diverse and distinctive self‐assembled structures in water, based on the control of the self‐assembly processes of artificial small molecules, has received considerable attention in supramolecular chemistry. Cage‐like perforated vesicles are distinctive and interesting self‐assembled structures. However, the development of self‐assembling molecules that can easily form perforated vesicles remains challenging. This paper reports a lower critical solution temperature (LCST) behavior‐triggered self‐assembly property of a 4‐aminoquinoline (4‐AQ)‐based amphiphile with a tetra(ethylene glycol) chain, in HEPES buffer (pH 7.4). This property allows to form perforated vesicles after heating at 80 °C (> LCST). The self‐assembly process of the 4‐AQ amphiphile can be controlled by heating at 80 °C (> LCST) or 60 °C (< LCST). After cooling to room temperature, the selective construction of the perforated vesicles and nanofibers was achieved from the same 4‐AQ amphiphile. Furthermore, the perforated vesicles exhibited slow morphological transformation into intertwined‐like nanofibers but were easily restored by brief heating above the LCST. [ABSTRACT FROM AUTHOR]

Pentacene is one of the most versatile organic semiconductors. New synthetic strategies to construct the pentacene skeleton are imperative to produce pentacene derivatives with appropriate solubility, stability, and optoelectronic properties for various applications. This paper describes a template-directed approach to pentacene derivatives. In the retrosynthesis, the acene skeleton is viewed as a laddered double strand polyene instead of the more intuitive linearly fused hexagons. Based on this vision, the template strand of polyene is constructed with Wittig olefination, whereas the second strand is accomplished with Knoevenagel condensation to produce pentacene and tetracene derivatives. The synthetic scheme is flexible enough to generate an array of acene derivatives with substitution patterns that were hitherto difficult to access. Amphiphilic pentacene and tetracene derivatives were also synthesized by the template strategy. One pentacene based amphiphilic rod-coil molecule undergoes self-assembly to form helical wire structures that were visualized with TEM. [ABSTRACT FROM AUTHOR]

Natural Aquaporin (AQP) channels are efficient water translocating proteins, rejecting ions. Inspired by this masterpiece of nature, Artificial Water Channels (AWCs) with controlled functional structures, can be potentially used to mimic the AQPs to a certain extent, offering flexible avenues toward biomimetic membranes for water purification. The objective of this paper is to trace the historical development and significant advancements of current reported AWCs. Meanwhile, we attempt to reveal important structural insights and supramolecular self‐assembly principles governing the selective water transport mechanisms, toward innovative AWC‐based biomimetic membranes for desalination. [ABSTRACT FROM AUTHOR]

Go nano! Cubelike Pt nanowire superstructures supported on vertically aligned bamboo‐shaped carbon nanotubes (see the FESEM image) are used as electrocatalysts for fuel cells. They exhibit remarkably improved stability over the commercial Pt/C catalyst made of Pt nanoparticles on amorphous carbon. [ABSTRACT FROM AUTHOR]

This Full Paper reports the formation of silver (Ag) NPs within spatially resolved two‐component hydrogel beads, which combine a low‐molecular‐weight gelator (LMWG) DBS‐CONHNH2 and a polymer gelator (PG) calcium alginate. The AgNPs are formed through in situ reduction of AgI, with the resulting nanoparticle‐loaded gels being characterised in detail. The antibacterial activity of the nanocomposite gel beads was tested against two drug‐resistant bacterial strains, often associated with hospital‐acquired infections: vancomycin‐resistant Enterococcus faecium (VRE) and Pseudomonas aeruginosa (PA14), and the AgNP‐loaded gels showed good antimicrobial properties against both types of bacteria. It is suggested that the gel bead format of these AgNP‐loaded hybrid hydrogels makes them promising versatile materials for potential applications in orthopaedics or wound healing. [ABSTRACT FROM AUTHOR]

Marseille–Provence is the European Capital of Culture in 2013. In this issue two articles from the Marseille‐based team Chirosciences analyze the role of imidazole alcohol hydrogen bonding in the nucleophlicity of dyad models (see the Full Paper by J. Leclaire, D. Bourissou, F. Fotiadu et al. on page 11301 ff.) and describe a facile synthesis and assemblies of tetraalkylporphyrins in two and three dimensions (see the Full Paper by Y. Kikkawa, T. S. Balaban et al. on page 11293 ff.). [ABSTRACT FROM AUTHOR]

Abstract: Two heptanuclear discs, [Co7(L1)6(CH3O)6]2+ (Co7‐L1) and [Co7(L2)12](ClO4)2 (Co7‐L2), have been prepared by the reaction of [Co(H2O)6](ClO4)2 with Schiff base HL1 (HL1=2‐methoxy‐6‐[(methylimino)methyl]phenolate) or benzimidazole derivative HL2 (HL2=(1H‐benzo[d]imidazol‐2‐yl)methanolate), respectively, at room temperature. In contrast, the reaction of [Co(H2O)6](ClO4)2 with a mixture of the two ligands, having similar coordination ability but different shapes, resulted in the butterfly‐structured tetranuclear cobalt cluster [Co4(L1)2(L2)4](ClO4)2⋅2H2O (Co4). Electrospray ionization mass spectrometry (ESI‐MS) analysis in real time revealed the {Co1}→{Co2}→{Co4}→{Co7} stepwise assembly when a single ligand was employed, but when both ligands were used only {Co4} was obtained, an intermediate of the former reactions. Interestingly, ligand competition was evidenced in the assembly process of the reaction with two ligands; for example, [Co4(L1)4(L2)2]2+ and [Co4(L1)3(L2)3]2+ were the primary clusters observed at the beginning of the reaction, but [Co4(L1)2(L2)4]2+ was the final product. This observation suggests ligand exchange is taking place, and DFT calculations confirmed that these transformations were possible. By varying the ratio of ligands, the abundance of a certain species in the competitive reaction could be controlled. [ABSTRACT FROM AUTHOR]

Covalently linked photosensitizer – catalyst dyads are one of the most elegant approaches in molecular “solar hydrogen” generation. In their Full Paper, Streb, Rau, Jacob et al. show how a family of polyoxometalate hydrogen evolution catalysts can be covalently linked to iridium complex photosensitizers. Visible ‐ light driven homogeneous hydrogen evolution is demonstrated and experimental as well as theoretical analyses give critical insights into the underlying features that govern catalytic activity. More information can be found in the Full Paper by Streb, Rau, Jacob et al. on page 15370. [ABSTRACT FROM AUTHOR]

The interaction of the self‐assembled trinuclear ruthenium bowl 13+, that displays three other accessible oxidation states, with oxo‐anions is investigated. Using a combination of NMR and electrochemical experimental data, estimates of the binding affinities of 14+, 15+, and 16+ for both halide and oxo‐anions were derived. This analysis revealed that, across the range of oxidation states of the host, both high anion binding affinities (>109 M−1 for specific guests bound to 16+) and high selectivities (a range of >107 M−1) were observed. As the crystal structure of binding of the hexafluorophosphate anion revealed that the host has two potential binding sites (named the α and β pockets), the host‐guest properties of both putative binding sites of the bowl, in all of its four oxidation states, were investigated through detailed quantum‐based computational studies. These studies revealed that, due to the interplay of ion‐ion interactions, charge‐assisted hydrogen‐bonding and anion‐π interactions, binding to the α pocket is generally preferred, except for the case of the relatively large and lipophilic hexafluorophosphate anionic guest and the host in the highest oxidation states, where the β pocket becomes relatively favourable. This analysis confirms that host‐guest interactions involving structurally complex supramolecular architectures are driven by a combination of non‐covalent interactions and, even in the case of charged binding pairs, simple ion‐ion interactions alone cannot accurately define these recognition processes. [ABSTRACT FROM AUTHOR]

The covalent attachment of molecular photosensitizers (PS) to polyoxometalates (POMs) opens new pathways to PS‐POM dyads for light‐driven charge‐transfer and charge‐storage. Here, we report a synthetic route for the covalent linkage of BODIPY‐dyes to Anderson‐type polyoxomolybdates by using CLICK chemistry (i. e. copper‐catalyzed azide‐alkyne cycloaddition, CuAAC). Photophysical properties of the dyad were investigated by combined experimental and theoretical methods and highlight the role of both sub‐components for the charge‐separation properties. The study demonstrates how CLICK chemistry can be used for the versatile linkage of organic functional units to molecular metal oxide clusters. [ABSTRACT FROM AUTHOR]

Helical architectures with controllable helical sense bias have recently attracted considerable interest for mimicking biological helices and developing novel chiral materials. Coordination polymers (CPs), composed of metal ion nodes and organic linkers, are intriguing systems showing tunable structures and functions. However, CPs with helical morphologies have rarely been explored so far. Particularly, chirality inversion through external stimulus has not been achieved in helical CPs. In this work, we carried out an in‐depth investigation on the self‐assembly of 1D gadolinium(III) phosphonate CPs using GdX3 (X=Cl, Br, I) and Gd(RSO3) (R=CH3, C6H5, CF3) as metal sources and R‐(1‐phenylethylamino)methyl phosphonic acid (R‐pempH2) as ligand. Superhelices were formed by precise control of the interchain interactions through different intercalated anions. Furthermore, the twisting direction of superhelices could be controlled by synergistic effect of anions and pH. This study may provide a new route to fabricate helical nanostructures of CPs with a desirable chiral sense and help understand the inner mechanism of the self‐assembly process of macroscopic helical structures of molecular systems. [ABSTRACT FROM AUTHOR]

Ordered molecular self‐assembly of glycoamphiphiles has been regarded as an attractive, practical and bottom‐up approach to obtain stable, structurally well‐defined, and functional mimics of natural polysaccharides. This study describes a versatile and rational design of carbohydrate‐based hydrogelators through N,N'‐substituted barbituric acid‐mediated Knoevenagel condensation onto unprotected carbohydrates in water. Amphiphilic N‐substituted β‐C‐maltosylbarbiturates self‐assembled into pH‐ and calcium‐triggered alginate‐like supramolecular hydrogel fibers with a multistimuli responsiveness to temperature, pH and competitive metal chelating agent. In addition, amphiphilic N,N'‐disubstituted β‐C‐maltosylbarbiturates formed vesicle gels in pure water that were scarcely observed for glyco‐hydrogelators. Finally, barbituric acid worked as a multitasking group allowing chemoselective ligation onto reducing‐end carbohydrates, structural diversity, stimuli‐sensitiveness, and supramolecular interactions by hydrogen bonding. [ABSTRACT FROM AUTHOR]

Supramolecular forces govern self-assembly and further determine the final morphologies of self-assemblies. However, how they control the morphology remains hitherto largely unknown. In this paper, we have discovered that the self-assembled nanostructures of rigid organic semiconductor chromophores can be finely controlled by the secondary forces by fine-tuning the surrounding environments. In particular, we used water/methanol/hydrochloric acid to tune the environment and observed five different phases that resulted from versatile molecular self-assemblies. The representative self-assembled nanostructures were nanotapes, nanoparticles and their 1D assemblies, rigid microplates, soft nanoplates, and hollow nanospheres and their 1D assemblies, respectively. The specific nanostructure formation is governed by the water fraction, Rw, and the concentration of hydrochloric acid, [HCl]. For instance, nanotapes formed at low [HCl] and Rw values, whereas hollow nanospheres formed when either the HCl concentration is high, or the water fraction is low, or both. The significance of this paper is that it provides a useful phase diagram by using Rw and [HCl] as two variables. Such a self-assembly phase diagram maps out the fine control that the secondary forces have on the self-assembled morphology, and thus allows one to guide the formation toward a desired nanostructure self-assembled from rigid organic semiconductor chromophores by simply adjusting the two key parameters of Rw and [HCl]. [ABSTRACT FROM AUTHOR]

In our bodies, a slight pH change causes remarkable activation or serious damage in the biological processes and continuously keeps biological homeostasis. Detection of such a slight pH change has been a constant demand in searching for unusual biological events. In this paper, we demonstrate a novel pH sensory system that has been achieved through a combination of charge neutralization by a slight pH change with aggregation-induced emission (AIE). We selected a cyano-functionalized oligo(phenylene-vinylene) (cyanoOPV) backbone for AIE and introduced ammonium-tethered boronic acid groups as a pH-dependent function. The self-assembling of these dyes ( OPV-Cn) was readily achieved by pH-dependent charge neutralization at the neutral pH region. This sensory system showed unusually sensitive pH responsiveness in a narrow pH range. Moreover, this pH change was observed in a biologically important neutral pH region. We therefore believe that this system is broadly applicable to detect the slight pH change occurring in the biological events. [ABSTRACT FROM AUTHOR]

Surface‐assisted hierarchical DNA origami assembly can be scaled up to produce highly homogeneous polycrystalline DNA origami lattices at the mica‐electrolyte interface over cm2 areas with only minor boundary effects at the substrate edges. At total DNA costs of € 0.12 per cm2, this large‐scale DNA origami nanopatterning technique holds great promise for the development and fabrication of versatile functional surfaces. For more details see the Full Paper by A. Keller, V. Linko et al. on page 8564 ff. [ABSTRACT FROM AUTHOR]

Tetraphenylmethane appended with four pyridylpyridinium units works as a scaffold to self‐assemble four ruthenium porphyrins in a tetrahedral shape‐persistent giant architecture. The resulting supramolecular structure has been characterised in the solid state by X‐ray single crystal analysis and in solution by various techniques. Multinuclear NMR spectroscopy confirms the 1 : 4 stoichiometry with the formation of a highly symmetric structure. The self‐assembly process can be monitored by changes of the redox potentials, as well as by modifications in the visible absorption spectrum of the ruthenium porphyrin and by a complete quenching of both the bright fluorescence of the tetracationic scaffold and the weak phosphorescence of the ruthenium porphyrin. An ultrafast photoinduced electron transfer is responsible for this quenching process. The lifetime of the resulting charge separated state (800 ps) is about four times longer in the giant supramolecular structure compared to the model 1 : 1 complex formed by the ruthenium porphyrin and a single pyridylpyridinium unit. Electron delocalization over the tetrameric pyridinium structure is likely to be responsible for this effect. [ABSTRACT FROM AUTHOR]

Our understanding of the factors affecting the stability of cyclic d/l peptide (CP) nanotubes remains underdeveloped. In this work, we investigate the impact of side chain alignment, hydrophobicity and charge on CP nanotube stability through X‐ray crystallography, NMR spectroscopy and molecular dynamics (MD) simulations. We characterise the distinct CP‐CP alignments that can form and identify stable and unstable dimers by MD simulation. We measure H‐bond half‐lives of synthesised CPs by 1H−D exchange experiments and find good correlation with predicted CP‐CP stabilities. We find that hydrophobic amino acids improve CP dimer stability but experimentally reduce solubility. Charged amino acids either increase or decrease CP dimer stability depending on the relative orientation and composition of charged groups. X‐ray crystal structures are solved for two CPs, revealing non‐tubular folded conformations. Ultimately, this work will assist the educated design of stable tubular structures for potential applications in biomedicine. [ABSTRACT FROM AUTHOR]

Polyoxometalates (POMs) have emerged as material of interest in many applications such as energy storage and conversion due to their redox activity and molecularly defined structure. However, especially for polyoxovanadates a lack of understanding between structural modifications and physicochemical properties remains. The present study leverages a lacunary dodecavanadate to systematically investigate the electronic effect of heterometal functionalization. While structural distortion affects the stability of the cluster, the redox potentials correlate with the overall cluster charge. Furthermore, we report the first bromide‐templated analogue of this cluster family. While the halide anion is crucial for the formation of the cluster, no major effect on the electrochemical properties is observed. By improving the understanding of structure‐property relationship in this work, we hope to enable a more predictable tuning of redox‐properties of polyoxovandates. [ABSTRACT FROM AUTHOR]

Despite their intrinsic hydrolysable character, imine bonds can become remarkably stable in water when self‐assembled in amphiphilic micellar structures. In this work, we systematically studied some of these structures and the influence of various parameters that can be used to take control of their hydrolysis, including pH, concentration, the position of the imine function in the amphiphilic structure, relative lengths of the linked hydrophilic and hydrophobic moieties. Thermodynamic and kinetic data led us to the rational design of stable imines in water, partly based on the location of the imine function within the hydrophobic part of the amphiphile and on a predictable quantitative term that we define as the total hydrophilic–lipophilic balance (HLB). In addition, we show that such stable systems are also stimuli‐responsive and therefore, of potential interest in trapping and releasing micellar components on demand. [ABSTRACT FROM AUTHOR]

The functionalization of photocatalytic metal oxide nanoparticles of TiO2, ZnO, WO3 and CuO with amine‐terminated (oleylamine) and thiol‐terminated (dodecane‐1‐thiol) alkyl‐chain ligands was studied under ambient conditions. A high selectivity was observed in the binding specificity of a ligand towards nanoparticles of these different oxides. It was observed that oleylamine binds stably to only TiO2 and WO3, whereas dodecane‐1‐thiol binds stably only to ZnO and CuO. Similarly, polar‐to‐nonpolar solvent phase transfer of TiO2 and WO3 nanoparticles could be achieved by using oleylamine, but not dodecane‐1‐thiol, whereas the opposite holds for ZnO and CuO. The surface chemistry of ligand‐functionalized nanoparticles was probed by attenuated total reflectance (ATR)‐FTIR spectroscopy, which enabled the occupation of the ligands at the active sites to be elucidated. The photostability of the ligands on the nanoparticle surface was determined by the photocatalytic self‐cleaning properties of the material. Although TiO2 and WO3 degrade the ligands within 24 h under both UV and visible light, ligands on ZnO and CuO remain unaffected. The gathered insights are also highly relevant from an application point of view. As an example, because the ligand‐functionalized nanoparticles are hydrophobic in nature, they can be self‐assembled at the air‐water interface to give nanoparticle films with demonstrated photocatalytic as well as anti‐fogging properties. [ABSTRACT FROM AUTHOR]

Luminescent copper(I)‐based compounds have recently attracted much attention since they can reach very high emission quantum yields. Interestingly, Cu(I) clusters can also be emissive, and the extension from small molecules to larger architecture could represent the first step towards novel materials that could be obtained by programming the units to undergo self‐assembly. However, for Cu(I) compounds the formation of supramolecular systems is challenging due to the coordinative diversity of copper centers. This works shows that this diversity can be exploited in the construction of responsive systems. In detail, the changes in the emissive profile of different aggregates formed in water by phosphine‐thioether copper(I) derivatives were followed. Our results demonstrate that the self‐assembly and disassembly of Cu(I)‐based coordination polymeric nanoparticles (CPNs) is sensitive to solvent composition. The solvent‐induced changes are related to modifications in the coordination sphere of copper at the molecular level, which alters not only the emission profile but also the morphology of the aggregates. Our findings are expected to inspire the construction of smart supramolecular systems based on dynamic coordinative metal centers. [ABSTRACT FROM AUTHOR]

This paper reports a small family of cationic surfactants designed to bind polyanions such as DNA and heparin. Each molecule has the same hydrophilic cationic ligand and a hydrophobic aliphatic group with eighteen carbon atoms with one, two, or three alkene groups within the hydrophobic chain (C18-1, C18-2 and C18-3). Dynamic light scattering indicates that more alkenes lead to geometric distortion, giving rise to larger self-assembled multivalent (SAMul) nanostructures. Mallard Blue and Ethidium Bromide dye displacement assays demonstrate that heparin and DNA have markedly different binding preferences, with heparin binding most effectively to C18-1, and DNA to C18-3, even though the molecular structural differences of these SAMul systems are buried in the hydrophobic core. Multiscale modelling suggests that adaptive heparin maximises enthalpically favourable interactions with C18-1, while shape-persistent DNA forms a similar number of interactions with each ligand display, but with slightly less entropic cost for binding to C18-3-fundamental thermodynamic differences in SAMul binding of heparin or DNA. This study therefore provides unique insight into electrostatic molecular recognition between highly charged nanoscale surfaces in biologically relevant systems. [ABSTRACT FROM AUTHOR]

The incorporation of functional groups into the cavity of discrete supramolecular coordination cages (SCCs) will bring unique functions and applications. Here, three dicarboxylate ligands (H2L1Cl, H2L2Cl and H2L3Cl) containing N‐heterocyclic carbene (NHC) precursors as linkers were introduced to construct SCCs by combining with two C3‐symmertic (CpZr)3(μ3‐O)(μ2‐OH)3 clusters as three‐connect vertices, resulted in a series of rugby‐like V2E3 (V=vertex, E=edge) type homoleptic cages (SCC‐1, SCC‐2 and SCC‐3). However, V4E6‐type tetrahedral cages (SCC‐4 and SCC‐5), incorporating six Au‐NHC moieties, were obtained when the corresponding NHC‐gold(I) functionalized ligands (H2L1Au, H2L2Au) were applied. For the first time, we present a trackable CpZr‐involved cage to cage conversion to generate a heteroleptic V2E3 cage (SCC‐6) from two homoleptic cages (SCC‐2 and SCC‐5) with different geometries of V2E3 and V4E6. The heteroleptic assembly SCC‐6 can also be formed upon a subcomponent displacement strategy. The structural transformation and reassembly processes were detected and monitored by 1H NMR spectroscopy and electrospray‐ionization mass spectrometry. The formation of heteroleptic assembly was further supported by single crystal X‐ray diffraction analysis. Moreover, homoleptic cage SCC‐2 possesses a trigonal bipyramidal cationic cavity allowing the encapsulation of a series of sulfonate anionic guests. [ABSTRACT FROM AUTHOR]

There is increasing interest in the development and applications of synthetic receptors that recognize target biomolecules in aqueous media. We have developed a new tweezer‐type synthetic receptor that gives a significant fluorescence response upon complexation with heme in aqueous solution at pH 7.4. The synthetic receptor consists of a tweezer‐type heme recognition site and sulfo‐Cy5 as a hydrophilic fluorophore. The receptor–heme complex exhibits a supramolecular amphiphilic character that facilitates the formation of self‐assembled aggregates, and both the tweezer moiety and the sulfo‐Cy5 moiety are important for this property. The synthetic receptor also exhibits significant fluorescence responses to biliverdin and bilirubin, but shows very weak fluorescence responses to flavin mononucleotide, folic acid, and nicotinamide adenine dinucleotide, which contain smaller π‐scaffolds. [ABSTRACT FROM AUTHOR]

In this study, photoswitchable fluorescent supramolecular metallacycles with high fatigue‐resistance have been constructed by coordination‐driven self‐assembly by using bithienylethene with dipyridyl units (BTE) as a coordination donor and a fluorescent di‐platinum(II) (Pt‐F) as a coordination acceptor. The photo‐triggered reversible transformation between the ring‐open and ring‐closed form of the metallacycles was confirmed by 1H NMR, 31P NMR, and UV/Vis spectroscopy. This unique property enabled a reversible noninvasive "off–on" switching of fluorescence through efficient Förster resonance energy transfer (FRET). Importantly, the metallacycles remained structurally intact after up to 10 photoswitching cycles. The photoresponsive property and exceptional photostability of the metallacycles posit their potential promising application in optical switching, image storage, and super‐resolution microscopy. [ABSTRACT FROM AUTHOR]

Herein, the photodynamic activity of phthalocyanine (pc)‐assembled nanoparticles against bacterial strains is demonstrated. The photosensitizers (PS) studied in this work are two chiral ZnIIPcs (PS‐1 and PS‐2), with an AABB geometry (where A and B refer to differently substituted isoindole constituents). They contain differently functionalized, chiral binaphthyloxy‐linked A isoindole units, which determine the hydrophobicity of the system, and cationic methyl pyridinium moieties in the other two isoindoles to embody hydrophilicity. Both compounds have the ability to self‐assemble into nanoparticles in aqueous media and have proved efficient in the photo‐inactivation of Staphylococcus aureus and Escherichia coli, selected as models of Gram‐positive and Gram‐negative bacteria. The average size of the nanoparticles was determined by substitution at the binaphthyl core and, in turn, influences the toxicity of the PS. Thus, PS‐1, presenting a nonsubstituted binaphthyl core, forms larger nanoparticles with a larger cationic surface than the octyl‐functionalized PS‐2. Although both PSs present similar structure and photophysical features, the self‐assembled nanostructures of PS‐1 are more effective at killing both types of strain, showing an outstanding photo‐inactivation capacity with the Gram‐negative E. coli. [ABSTRACT FROM AUTHOR]

The formation of supramolecular structural units through self‐assembly is a powerful method to design new architectures and materials endowed with specific properties. With the aim of adding a group of versatile tectons to the toolkit of crystal engineers, we have devised and synthesised four new V‐shaped building blocks characterised by an aryl acetylene scaffold comprising three substituted pyridine rings connected by two triple bonds. The judicious choice of different substituents on the pyridine rings provides these tectons with distinctive steric, electrostatic and self‐assembly properties, which influence their crystal structures and their ability to form co‐crystals. Co‐crystals of the tectons with tetraiododifluorobenzene were obtained both via traditional and mechanochemical crystallisation strategies, proving their potential use in crystal engineering. The energetic contributions of the supramolecular interactions at play in the crystal lattice have also been evaluated to better understand their nature and strength and to rationalise their role in designing molecular crystals. [ABSTRACT FROM AUTHOR]

Understanding the relationship between molecular design and packing modes constitutes one of the major challenges in self‐assembly and is essential for the preparation of functional materials. Herein, we have achieved high precision control over the supramolecular packing of amphiphilic PtII complexes by systematic variation of the hydrophilic side‐chain length. A novel approach of general applicability based on complementary X‐ray diffraction and solid‐state NMR spectroscopy has allowed us to establish a clear correlation between molecular features and supramolecular ordering. Systematically increasing the side‐chain length gradually increases the steric demand and reduces the extent of aromatic interactions, thereby inducing a gradual shift in the molecular packing from parallel to a long‐slipped organization. Notably, our findings highlight the necessity of advanced solid‐state NMR techniques to gain structural information for supramolecular systems where single‐crystal growth is not possible. Our work further demonstrates a new molecular design strategy to modulate aromatic interaction strengths and packing arrangements that could be useful for the engineering of functional materials based on PtII and aromatic molecules. [ABSTRACT FROM AUTHOR]

Cyanuric acid (CA), a triazine heterocycle, is extensively utilized for noncovalent self‐assembly. The association between poly(adenine) and CA into micron‐length fibers was a remarkable observation made by Sleiman and co‐workers, who proposed that adenine and CA adopt a hexameric rosette configuration in analogy with previously reported structures for CA assemblies. However, recent experimental observations from the Krishnamurthy group led to a reevaluation of the hexameric rosette model, wherein they have proposed a hydrogen‐bonded helicene model as an alternative. Our molecular dynamics simulations show that the hexad model is indeed unlikely and that this novel noncovalent helicene geometry, where the adenine and CA bases form an extended helical hydrogen‐bond network across the system, is a more probable structural motif. The existence of noncovalent helicene compounds may have wide‐ranging applications in DNA nanotechnology and helicene chemistry. [ABSTRACT FROM AUTHOR]

Accumulation and aggregation of the intrinsically disordered protein α‐synuclein (α‐Syn) into amyloid fibrils are hallmarks of a series of heterogeneous neurodegenerative disorders, known as synucleinopathies and most notably Parkinson's disease (PD). The crucial role of α‐Syn aggregation in PD makes it an attractive target for the development of disease‐modifying therapeutics that would inhibit α‐Syn aggregation or disrupt its preformed fibrillar assemblies. To this end, we have designed and synthesized two naphthoquinone–dopamine‐based hybrid small molecules, NQDA and Cl‐NQDA, and demonstrated their ability to inhibit in vitro amyloid formation by α‐Syn using ThT assay, CD, TEM, and Congo red birefringence. Moreover, these hybrid molecules efficiently disassembled preformed fibrils of α‐Syn into nontoxic species, as evident from LUV leakage assay. NQDA and Cl‐NQDA were found to have low cytotoxicity and they attenuated the toxicity induced by α‐Syn towards SH‐SY5Y neuroblastoma cells. NQDA was found to efficiently cross an in vitro human blood–brain barrier model. These naphthoquinone–dopamine based derivatives can be an attractive scaffold for therapeutic design towards PD. [ABSTRACT FROM AUTHOR]

Simple particle counting cannot in general be reliably employed to predict the observed architecture as DFT analysis shows that vibrational contributions to entropy dominate and may significantly influence the preferred architecture. However, simple particle counting, which predicts triangles over squares, is seen to be correct here, and DFT confirms the triangles are energetically favored over the corresponding squares. Image kindly created by Michael Crawford (Dunedin). More information can be found in the Full Paper by A. L. Garden, S. Brooker et al. on page 14193. [ABSTRACT FROM AUTHOR]

In comparison with the hybridization with 0D TiO2 nanoparticle, 2D layered TiO2 nanosheets are much more effective in the improvement of the photocatalytic activity and photostability of semiconducting compounds. The 2D TiO2-Ag3PO4 nanohybrid described in this paper shows a greater decrease in the electron-hole recombination upon hybridization and a stronger chemical interaction between the components than the 0D homologue. This result confirms the benefits of 2D layered TiO2 nanosheets as a building block for efficient hybrid-type photocatalyst materials. [ABSTRACT FROM AUTHOR]

Quantum chemical calculations were used to study the reaction of carboxylic acids with isonitriles inside a resorcinarene‐based self‐assembled capsule. Experimentally, it has been shown that the reactions between p‐tolylacetic acid and n‐butyl isonitrile or isopropyl isonitrile behave differently in the presence of the capsule compared both with each other and also with their solution counterparts. Herein, the reasons for these divergent behaviors are addressed by comparing the detailed energy profiles for the reactions of the two isonitriles inside and outside the capsule. An energy decomposition analysis was conducted to quantify the different factors affecting the reactivity. The calculations reproduce the experimental findings very well. Thus, encapsulation leads to lowering of the energy barrier for the first step of the reaction, the concerted α‐addition and proton transfer, which in solution is rate‐determining, and this explains the rate acceleration observed in the presence of the capsule. The barrier for the final step of the reaction, the 1,3 O→N acyl transfer, is calculated to be higher with the isopropyl substituent inside the capsule compared with n‐butyl. With the isopropyl substituent, the transition state and the product of this step are significantly shorter than the preceding intermediate, and this results in energetically unfavorable empty spaces inside the capsule, which cause a higher barrier. With the n‐butyl substituent, on the other hand, the carbon chain can untwine and hence uphold an appropriate guest length. [ABSTRACT FROM AUTHOR]

Tetramethylaluminato/halogenido(X) ligand exchange reactions in half‐sandwich complexes [CpRLa(AlMe4)2] are feasible in non‐coordinating solvents and provide access to large coordination clusters of the type [CpRLaX2]x. Incomplete exchange reactions generate the hexalanthanum clusters [CpR6La6X8(AlMe4)4] (CpR=Cp*=C5Me5, X=I; CpR=Cp′=C5H4SiMe3, X=Br, I). Treatment of [Cp*La(AlMe4)2] with two equivalents Me3SiI gave the nonalanthanum cluster [Cp*LaI2]9, while the exhaustive reaction of [Cp′La(AlMe4)2] with the halogenido transfer reagents Me3GeX and Me3SiX (X=I, Br, Cl) produced a series of monocyclopentadienyl rare‐earth‐metal clusters with distinct nuclearity. Depending on the halogenido ion size the homometallic clusters [Cp′LaCl2]10 and [Cp′LaX2]12 (X=Br, I) could be isolated, whereas different crystallization techniques led to the aggregation of clusters of distinct structural motifs, including the desilylated cyclopentadienyl‐bridged cluster [(μ‐Cp)2Cp′8La8I14] and the heteroaluminato derivative [Cp′10La10Br18(AlBr2Me2)2]. The use of the Cp′ ancillary ligand facilitates cluster characterization by means of NMR spectroscopy. [ABSTRACT FROM AUTHOR]

The nuclear coactivator binding domain (NCBD) of transcriptional co‐regulator CREB‐binding protein (CBP) is an example of conformationally malleable proteins that can bind to structurally unrelated protein targets and adopt distinct folds in the respective protein complexes. Here, we show that the folding landscape of NCBD contains an alternative pathway that results in protein aggregation and self‐assembly into amyloid fibers. The initial steps of such protein misfolding are driven by intermolecular interactions of its N‐terminal α‐helix bringing multiple NCBD molecules into contact. These oligomers then undergo slow but progressive interconversion into β‐sheet‐containing aggregates. To reveal the concealed aggregation potential of NCBD we used a chemically synthesized mirror‐image d‐NCBD form. The addition of d‐NCBD promoted self‐assembly into amyloid precipitates presumably due to formation of thermodynamically more stable racemic β‐sheet structures. The unexpected aggregation of NCBD needs to be taken into consideration given the multitude of protein–protein interactions and resulting biological functions mediated by CBP. [ABSTRACT FROM AUTHOR]

Besides their widespread use in coordination chemistry, 2,2'‐bipyridines are known for their ability to undergo cis–trans conformational changes in response to metal ions and acids, which has been primarily investigated at the molecular level. However, the exploitation of such conformational switching in self‐assembly has remained unexplored. In this work, the use of 2,2'‐bipyridines as acid‐responsive conformational switches to tune supramolecular polymerization processes has been demonstrated. To achieve this goal, we have designed a bipyridine‐based linear bolaamphiphile, 1, that forms ordered supramolecular polymers in aqueous media through cooperative aromatic and hydrophobic interactions. Interestingly, addition of acid (TFA) induces the monoprotonation of the 2,2'‐bipyridine moiety, leading to a switch in the molecular conformation from a linear (trans) to a V‐shaped (cis) state. This increase in molecular distortion along with electrostatic repulsions of the positively charged bipyridine‐H+ units attenuate the aggregation tendency and induce a transformation from long fibers to shorter thinner fibers. Our findings may contribute to opening up new directions in molecular switches and stimuli‐responsive supramolecular materials. [ABSTRACT FROM AUTHOR]

Hydrogen bonds can efficiently guide the self‐assembly of organic materials, enabling to tune the properties of the aggregation processes. In the case of π‐conjugated materials, several parameters such as temperature, concentration and solvent can be used to modify the aggregation state while tuning the optoelectronic properties. Chirality can be included within the impacting parameters due to the differences in molecular packing. Here, chiral and achiral thiophene‐capped diketopyrrolopyrrole derivatives were designed and synthesized containing amide bonds, with the aim to study the interplay between chiral assemblies and their stabilization through hydrogen‐bonding. Differences in aggregation properties were observed with spectroscopy and microscopy, and a contactless microwave‐based technique was used to study their intrinsic charge carrier mobility. The positive role of hydrogen‐bonding has been highlighted and the differences between chiral and achiral compounds have been elucidated. [ABSTRACT FROM AUTHOR]

The rational control of the electrochemical properties of polyoxovanadate‐alkoxide clusters is dependent on understanding the influence of various synthetic modifications on the overall redox processes of these systems. In this work, the electronic consequences of ligand substitution at the heteroion in a heterometal‐functionalized cluster was examined. The redox properties of [V5O6(OCH3)12FeCl] (1‐[V5FeCl]) and [V5O6(OCH3)12Fe]X (2‐[V5Fe]X; X=ClO4, OTf) were compared in order to assess the effects of changing the coordination environment around the iron center on the electrochemical properties of the cluster. Coordination of a chloride anion to iron leads to an anodic shift in redox events. Theoretical modelling of the electronic structure of these heterometal‐functionalized clusters reveals that differences in the redox profiles of 1‐[V5FeCl] and 2‐[V5Fe]X arise from changes in the number of ligands surrounding the iron center (e.g. 6‐coordinate vs. 5‐coordinate). Specifically, binding of the chloride to the sixth coordination site appears to change the orbital interaction between the iron and the delocalized electronic structure of the mixed‐valent polyoxovanadate core. Tuning the heterometal coordination environment can therefore be used to modulate the redox properties of the whole cluster. [ABSTRACT FROM AUTHOR]

Pseudo‐isocyanine chloride (PIC) is a cationic dyestuff that exhibits self‐assembly in aqueous solution, promoted either by increasing the PIC concentration or by decreasing the temperature. PIC‐aggregates exhibit a characteristic and sharp absorption band as well as a fluorescence band at a wavelength of 573 nm making PIC an interesting candidate to analyze the self‐assembly process in various environments. The present work developed PIC‐based, synthetic model systems, suitable to investigate how macromolecular crowding influences self‐assembly processes. Four synthetic additives were used as potential crowders: Triethylene glycol (TEG), polyethylene glycol (PEG), Ficoll 400 as a highly branched polysaccharide, and sucrose corresponding to the monomeric unit of Ficoll. Combined UV/Vis spectroscopy and time‐resolved light scattering revealed a strong impact of crowding based on excluded volume effects only for Ficoll 400. Sucrose had hardly any influence on the self‐assembly of PIC and PEG and TEG impeded the PIC self‐assembly. Development of such a PIC based model system led over to in‐cell experiments. HeLa cells were infiltrated with PIC solutions well below the aggregation threshold in the infiltrating solution. In the cellular environment, PIC was exposed to a significant crowding and immediately started to aggregate. As was demonstrated by fluorescence imaging, the extent of aggregation can be modulated by exposing the cells to salt‐induced osmotic stress. The results suggest future use of such a system as a sensor for the analysis of in vitro and in vivo crowding effects on self‐assembly processes. [ABSTRACT FROM AUTHOR]

Octa‐ and tetrafluorinated bisanthene derivatives were synthesized for investigating the effect of electronegative fluorine substitution on the structure and physical property of bisanthene. Notably, a triisopropylsilylethynyl‐substituted octafluorinated derivative exhibited strong fluorescence with high fluorescence quantum yield and excellent photostability. Moreover, the derivative self‐assembled to form bundles of long semicrystalline nanofibers exhibiting hole‐transporting properties, see the Full Paper by H. Yamada et al. on page 7000. [ABSTRACT FROM AUTHOR]

NMR analysis reveals that quartet assemblies formed by a guanosine building block in solution can transform into a mixture of quartet (Q) and ribbon (R) ‐ like assemblies after solvent evaporation. Our results demonstrate that the existence of a stable supramolecular structure in solution or in the solid state may not reflect its stability and integrity in another phase. More information can be found in the Full Paper by S. P. Brown et al. on page 2315 ff. [ABSTRACT FROM AUTHOR]

This paper reports that Janus AuNi nanoparticles (JANNPs) can self-assemble onto silica spheres in a novel way, which is different from that of single-component isotropic nanoparticles. JANNPs modified with octadecylamine (ODA) assemble onto catechol-modified silica spheres (SiO2OH) to form a very special core-loop complex structure and finally the core-loop assemblies link each other to form large assemblies through capillary force and the hydrophobic interaction of the alkyl chains of ODA. The nanocomposites disassemble in the presence of vanillin and oleic acid because of the breakage of the catechol-metal link. Vanillin-induced disassembly enables the JANNPs to reassemble into a core-loop structure upon ODA addition. The assembly of SiO2OH and isotropic Ni or Fe3O4 particles generates traditional core-satellite structures. This unconventional self-assembly can be attributed to the synergistic effect of Janus specificity and capillary force, which is also confirmed by the assembly of thiol-terminated silica spheres (SHSiO2) with anisotropic JANNPs, isotropic Au, and Ni nanoparticles. These results can guide the development of novel composite materials using Janus nanoparticles as the primary building blocks. [ABSTRACT FROM AUTHOR]

With the rapid progress in the development of supramolecular soft materials, examples of low-molecularweight gelators (LMWGs) with the ability to immobilise both water and organic solvents by the same structural scaffold are very limited. In this paper, we report the development of pyrene-containing peptide-based ambidextrous gelators (AGs) with the ability to efficiently gelate both organic and aqueous solvents. The organo- and hydrogelation efficiencies of these gelators are in the range 0.7–1.1% w/v in various organic solvents and 0.5–5% w/v in water at certain acidic pH values (pH 2.0–4.0). Moreover, for the first time, AGs have been utilised to prepare single-walled carbonnanotube (SWNT)-included soft nanocomposites in both hydro- and organogel matrices. The influence of different non-covalent interactions such as hydrogen bonding, hydrophobic, π–π and van der Waals interactions in self-assembled gelation has been studied in detail by circular dichroism, FTIR, variable-temperature NMR, 2D NOESY and luminescence spectroscopy. Interestingly, the presence of the pyrene moiety in the structure rendered these AGs intrinsically fluorescent, which was quenched upon successful integration of the SWNTs within the gel. The prepared hydroand organogels along with their SWNT-integrated nanocomposites are thermoreversible in nature. The supramolecular morphologies of the dried gels and SWNT–gel nanocomposites have been studied by transmission electron microscopy, fluorescence microscopy and polarising optical microscopy, which confirmed the presence of three-dimensional self-assembled fibrillar networks (SAFINs) as well as the integrated SWNTs. Importantly, rheological studies revealed that the inclusion of SWNTs within the ambidextrous gels improved the mechanical rigidity of the resulting soft nanocomposites up to 3.8-fold relative to the native gels. [ABSTRACT FROM AUTHOR]

The internal cavity size of a metallosupramolecular assembly can be tuned by thoughtful design of the ligand. This work reports the introduction of imidazo[1,5‐a]pyridine scaffolds in place of the conventional imidazol‐2‐ylidene moieties, which resulted in new molecular containers bearing significantly enlarged cavities. The new hexacarbene metal assemblies can easily accommodate a dimethylsulfoxide molecule as a molecular guest. This is the first study of a unique "host–guest" system featuring an organometallic cylinder‐like cage exclusively derived from poly‐NHC ligands. More information can be found in the Full Paper by Y.‐F. Han et al. on page 5472. [ABSTRACT FROM AUTHOR]

Foldectures are typically formed from foldamers carrying a Boc group at the N‐terminus, which creates a network of N−H⋅⋅⋅O hydrogen bonds linking adjacent foldamers in head‐to‐tail packing modes. Although much less sterically demanding, cyclopropanoyl amides feature additionally an α‐proton known to form Cα−H⋅⋅⋅O hydrogen bonds with electron‐rich partners. Experimental and computational investigations of the tractable model system revealed that the strength of this secondary noncovalent interaction was sufficient to influence self‐assembly of foldamers. More information can be found in the Full Paper by R. W. Driver, M.‐H. Baik, and H.‐S. Lee et al. on page 2226. [ABSTRACT FROM AUTHOR]

Lipid–porphyrin conjugates are considered as promising building blocks for supramolecular structures with multifunctional properties such as those required for anticancer photodynamic therapy. The Full Paper by A. Makky et al. on page 19179 ff. describes the synthesis of two new lipid‐porphyrin conjugates by coupling chlorophyll‐a derivative, pheophorbide‐a, to natural phospholipids. These conjugates exhibited self‐assembling properties, high loading rate in liposomes membranes, interesting optical behavior and promising photodynamic activity with better selectivity in vitro to esophageal squamous cell carcinoma relative to normal cells. [ABSTRACT FROM AUTHOR]