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A rechargeable acidic polymer–air battery was firstly fabricated with poly(2,5-dihydroxy-1,4-benzoquinone-3,6-methylene) (PDBM) as the anode, the conventional Pt/C cathode catalyst, and acidic aqueous electrolyte (pH 1). This battery yielded a high discharging capacity of 349 mA h gpolymer−1 with a long-lifetime of >500 cycles and high rate capabilities (up to 10C). [ABSTRACT FROM AUTHOR]

Structural transformability accompanied by molecular accommodation is a distinguished feature of porous coordination polymers (PCPs) among porous materials. Conventional X-ray crystallography allows for the determination of each structural phase emerged during transformation. However, the propagation mechanism of transformation through an entire crystal still remains in question. Here we elucidate the structural nature of the spatial transient state, in which two different but correlated framework structures, an original phase and a deformed phase, simultaneously exist in one crystal. The deformed phase is distinctively generated only at the crystal surface region by introducing large guest molecules, while the remaining part of crystal containing small molecules maintains the original phase. By means of grazing incidence diffraction techniques we determine that the framework is sheared with sharing one edge of the original primitive cubic structure, leading to the formation of crystal domains with four mirror image relationships. [ABSTRACT FROM AUTHOR]

Flexible porous coordination polymers change their structure in response to molecular incorporation but recover their original configuration after the guest has been removed. We demonstrated that the crystal downsizing of twofold interpenetrated frameworks of [Cu2(dicarboxylate)2(amine)]n regulates the structural flexibility and induces a shape-memory effect in the coordination frameworks. In addition to the two structures that contribute to the sorption process (that is, a nonporous closed phase and a guest-included open phase), we isolated an unusual, metastable open dried phase when downsizing the crystals to the mesoscale, and the dosed phase was recovered by thermal treatment. Crystal downsizing suppressed the structural mobility and stabilized the open dried phase. The successful isolation of two interconvertible empty phases, the closed phase and the open dried phase, provided switchable sorption properties with or without gate-opening behavior. [ABSTRACT FROM AUTHOR]

Janus ‐ MOF: Dünne Filme aus nicht ‐ zentrosymmetrischen heterostrukturierten Metall ‐ organischen Gerüsten (MOFs) wurden direkt auf QCM ‐ Sensoren hergestellt (QCM=Quarzkristall ‐ Mikrowaage). Abhängig von der räumlichen Anordnung der zwei Gerüste konnten die dünnen MOF ‐ Filme die Affinität für Analyten steuern und so den QCM ‐ Sensoren hohe Selektivität verleihen. [ABSTRACT FROM AUTHOR]

Janus MOF: Thin films consisting of non‐centrosymmetric heterostructured metal–organic frameworks (MOFs) were fabricated directly on quartz‐crystal microbalance (QCM) sensor devices. Depending on the spatial configuration of two frameworks, the thin MOF films could tune the affinity for analytes, thus giving high selectivity to the QCM sensors. [ABSTRACT FROM AUTHOR]

The spatial organization of porous coordination polymer (PCP) crystals into higher-order structures is critical for their integration into separation systems, heterogeneous catalysts, ion/electron transport and photonic devices. Here, we demonstrate a rapid method to spatially control the nucleation site, leading to the formation of mesoscopic architecture made of PCPs, in both two and three dimensions. Inspired by geological processes, this method relies on the morphological replacement of a shaped sacrificial metal oxide used both as a metal source and as an 'architecture-directing agent' by an analogous PCP architecture. Spatiotemporal harmonization of the metal oxide dissolution and the PCP crystallization allowed the preservation of very fine mineral morphological details of periodic alumina inverse opal structures. The replication of randomly structured alumina aerogels resulted in a PCP architecture with hierarchical porosity in which the hydrophobic micropores of the PCP and the mesopores/macropores inherited from the parent aerogels synergistically enhanced the material's selectivity and mass transfer for water/ethanol separation. [ABSTRACT FROM AUTHOR]

The supramolecular organization of a new polychlorotriphenyl (PTM) radical bearing three long alkyl chains has been studied by scanning tunneling microscopy (STM) at the liquid-solid interface. This radical hierarchically self-assembles on graphite forming head-to-head dimers that organize in rows following an interesting spin-containing two-leg molecular ladder topology, in which the alkyl chains determine the space between the radical rows and act as diamagnetic barriers. In addition, these double-rows also self- assemble three-dimensionally, leading to a multilayer organization which is still influenced by the HOPG substrate symmetry. The observed nanostructures are sustained by different intermolecular interactions such as Cl⋯Cl, Cl⋯Ph, π-π, van der Waals, and CH⋯r interactions. Theoretical calculations were used to model the observed assemblies, and the results were in complete agreement with the experimental data. Remarkably, atomic force microscopy (AFM) studies confirmed that this tendency to form double rows composed by the PTM magnetic heads surrounded by the alkyl chains is maintained after the complete evaporation of the solvent. The electrochemical and magnetic properties of these PTM nanostructures were also demonstrated. [ABSTRACT FROM AUTHOR]

The self-assembly of a series of hexadehydrotribenzo[12]annulene (DBA) derivatives has been scrutinized by scanning tunneling microscopy (STM) at the liquid-solid interface. First, the influence of core symmetry on the network structure was investigated by comparing the two-dimensional (2D) ordering of rhombic bisDBA la and triangular DBA 2a (Figure 1). BisDBA la forms a Kagome network upon physisorption from 1,2,4-trichlorobenzene (TCB) onto highly oriented pyrolytic graphite (HOPG). Under similar experimental conditions, DBA 2a shows the formation of a honeycomb network. The core symmetry and location of alkyl substituents determine the network structure. The most remarkable feature of the DBA networks is the interdigitation of the nonpolar alkyl chains: they connect the π-conjugated cores and direct their orientation. As a result, 2D open networks with voids are formed. Second, the effect of alkyl chain length on the structure of DBA patterns was investigated. Upon increasing the length of the alkyl chains (DBAs 3c-e) a transition from honeycomb networks to linear networks was observed in TCB, an observation attributed to stronger molecule—substrate interactions. Third, the effect of solvent on the structure of the nonpolar DBA networks was investigated in four different solvents: TCB as a polar aromatic solvent, 1-phenyloctane as a solvent having both aromatic and aliphatic moieties, n-tetradecane as an aliphatic solvent, and octanoic acid as a polar alkylated solvent. The solvent dramatically changes the structure of the DBA networks. The solvent effects are discussed in terms of factors that influence the mobility of molecules at the liquid-solid interface such as solvation. [ABSTRACT FROM AUTHOR]

A one-pot reaction of a cationic diruthenium complex, [Ru2II,III(O2CCH3)4(THF)2](BF4), with arylcarboxylic acids, ArCO2H, (PhCO2H = benzoic acid, NapCO2H = 1-naphthoic acid, AntCO2H = 9-anthracenecarboxylic acid) in NDMA (NDMA = N,N-dimethylaniline) has led to isolation of neutral paddlewheel-type diruthenium complexes, [RuII2(O2CAr)4-(THF)2] (Ar = Ph (1), Nap (2), Ant (3)). Paramagnetic variable temperature (VT) 1H NMR studies and GC-MS studies show that the reaction consists of two steps: a one-electron reduction of the Ru2 core by NDMA and a simple carboxylate-exchange reaction. All compounds 1–3 were structurally characterized by X-ray crystallography. While the structural features of the Ru2 core are very similar in all the compounds, the dihedral angles between the carboxylate plane and the aromatic ring are larger with the expanding of aryl groups from phenyl to anthracene. The effect of π-π stacking leads to the formation of a 1-D chain structure in compound 3, whereas compounds 1 and 2 are fully isolated from each other. The electrochemical measurements show that the quasireversible one-electron oxidation step is observed at +0.06, +0.09, and +0.17 V (vs Ag/Ag+) for 1–3, respectively, assigned to the RuII2RuII,III2 redox couple. These potentials are found to demonstrate a linear relationship with the substituent constants for aryl compounds, (σπ,B-. [ABSTRACT FROM AUTHOR]

Aerogels are porous ultralight materials known for their high porosity, wide range of pore sizes, low density, and good macroscopic mechanical properties, all of which make them promising candidates for shaped adsorbents, catalysts, and insulators, among other applications. Here, this work reports a new approach that enables both the formation of modular aerogels, via dynamic covalent chemistry, and their post‐synthetic modification, via coordination chemistry. To demonstrate this strategy, this work first polymerizes porous amino‐functionalized Rh(II)‐based metal‐organic polyhedra (MOPs) with aldehydes, which afforded robust imine‐gel networks that is then converted into aerogels. Next, this work functionalizes these aerogels through the coordination of ligands on the axial site of Rh(II) paddlewheels of the MOP. Interestingly, in this chemistry, the local changes in the coordination site of the MOPs are transferred to the overall aerogel, thereby altering its macroscopic physicochemical properties. Importantly, this feature enables the synthesis of optimized adsorbents tailored to specific guests, as this work demonstrates through a series of experiments using ligands of different electrostatic and hydrophobic characters. [ABSTRACT FROM AUTHOR]

The article focuses on the two-dimensional crystal structure of two dehydrobenzol[12]annulene derivatives. A molecular Kagomé network within a 2D crystal on a surface is presented. Key elements to control molecular network formation are core symmetry, location and orientation of interacting and connecting substituents, and symmetry matching between the networks and surface.

Although metal–organic frameworks (MOFs) have been shown to catalyse a wide range of reactions, understanding the influence of nanoscale structuralisation (e.g. crystal size and morphology) on their performance is a difficult challenge. Here, we have prepared Zn(2-mIM)2 (ZIF-8; 2-mIM− = 2-methylimidazolate) crystals of varied size and morphology, and studied the catalytic properties of these samples in the context of the transesterification of vinyl acetate with hexanol. ZIF-8 has previously been shown to catalyse reactions at Lewis acidic sites at the crystal surface and at defect sites. The substrates were selected as they are significantly larger than the pore apertures, allowing the reaction to be confined to the surface of the crystals and providing the best opportunity to understand the influence of the structuralisation on the observed properties. In this case, the rate of hexyl acetate production increased as the crystal size was reduced; however, the effect of crystal morphology on the rate of reaction was not appreciable due to the instability of ZIF-8 under catalytic conditions. It was clearly observed that the surface of ZIF-8 was unstable in catalytic conditions featuring hydrophobic reagents with a polar functional groups, with scanning electron microscopy (SEM) revealing indiscriminate etching of all crystal surfaces. Atomic adsorption spectrometry (AAS) analyses confirmed the etching led to significant leaching of Zn2+, which was observed to contribute considerably to the catalytic activity of ZIF-8. Our results highlight the need for fundamental characterisation of MOF catalysts to enable their deployment under a wider variety of catalytic conditions. [ABSTRACT FROM AUTHOR]

Taking advantage of the outstanding properties of a naphthalenediimide-based entangled porous coordination polymer, a simple strategy for the achievement of white light emission is herein presented. The dynamic structural transformation of the [Zn2(bdc)2(dpNDI)]n metal-organic framework enhances the interactions with aryl-guests giving rise to different luminescence colors upon UV (ultraviolet) illumination. Thus, through the rational selection of those small aromatic guest molecules with different electron donor substituents at the appropriate proportion, the emission color was tuned by mixture ratio of guest molecules and even white light emission was achieved. Furthermore, domains in large crystals with a complementary response to linearly polarized light were noticed. [ABSTRACT FROM AUTHOR]

Review: [28 refs. [ABSTRACT FROM AUTHOR]

Nanoparticles exhibiting enzymatic functions have garnered considerable attention due to their structural robustness and the profusion of active sites that can be introduced to a single nanosized particle. Here we report that nanosized mixed‐metal zeolitic imidazolate frameworks (ZIFs) show a superoxide dismutase (SOD)‐like catalytic activity. We chose a ZIF composed of copper and zinc ions and 2‐methylimidazole, CuZn‐ZIF‐8, in which the Cu and Zn ions are bridged by an imidazolato ligand. This coordination geometry closely mimics the active site of CuZn superoxide dismutase (CuZnSOD). The CuZn‐ZIF‐8 nanoparticles exhibit potent SOD‐like activity, attributed to their porous nature and numerous copper active sites, and also possess exceptional recyclability. [ABSTRACT FROM AUTHOR]

Three new ligands containing a bicyclo[2.2.2]oct‐7‐ene‐2,3,5,6‐tetracarboxydiimide unit have been used to assemble lantern‐type metal‐organic cages with the general formula [Cu4L4]. Functionalisation of the backbone of the ligands leads to distinct crystal packing motifs between the three cages, as observed with single‐crystal X‐ray diffraction. The three cages vary in their gas sorption behaviour, and the capacity of the materials for CO2 is found to depend on the activation conditions: softer activation conditions lead to superior uptake, and one of the cages displays the highest BET surface area found for lantern‐type cages so far. [ABSTRACT FROM AUTHOR]

The development of nitric oxide (NO) releasing materials has been of significant importance due to their application in cell biology and biomedicine. Besides the macromolecular scaffold dangling NO releasing moiety, porous materials have been used to host such NO releasing molecules. Here we synthesized a series of porous coordination polymers (PCPs), in which N-nitrosamine functional groups as photoactive NO donors were introduced into the framework scaffolds by post-synthetic nitrosation of amine functionalized analogous PCPs. We further demonstrated a controlled release of NO from the PCPs by light irradiation. Though isoreticular frameworks based on octanuclear clusters of titanium or aluminium ions were chosen due to their water-stability, the frameworks showed difference in stability in cell culture media; while aluminium frameworks were less stable in water and physiological media, the titanium analogue was highly stable even under physiological conditions. [ABSTRACT FROM AUTHOR]

We report the synthesis of photoactive carbon monoxide-releasing coordination polymer particles through the assembly of Mn(I) carbonyl complexes with bis(imidazole) ligands. The use of Mn(I) carbonyl complexes as metallic nodes in the coordination network avoids the potential for aggregation-induced self-quenching, favouring their use in the solid state. [ABSTRACT FROM AUTHOR]

Vanadium-based porous coordination polymers (or metal-organic frameworks) possess both porous and electronic properties, which make these new materials appealing for applications in molecular separation, sensing and heterogeneous catalysis. Their integration into systems that fully exploit their intrinsic properties requires versatile methods allowing assembly of the PCP crystals into well-defined films, patterns, fibers or the formation of heterostructures. In this contribution, polycrystalline macrostructures and heterostructures made of ijVIJOH)ndc]n (ndc = 1,4-naphthalenedicarboxylate) PCP crystals were synthesized through a dissolution-recrystallization process, so-called coordination replication, where a pre-shaped V2O5 sacrificial phase was replaced by well-intergrown PCP crystals in the presence of H2ndc as an organic linker and under a reductive environment. In this process, V2O5 acts both as the metal source and as the template that provides the shape to the resulting mesoscopic polycrystalline architecture. Ascorbic acid, acting as the reducing agent, both promotes the dissolution of the sacrificial V2O5 phase and provides the VIII species required for the construction of the [V(OH)ndc]n framework. Two-dimensional patterns were successfully synthesized by applying this procedure. [ABSTRACT FROM AUTHOR]

There is growing interest in metal–organic cages (MOCs) as porous materials owing to their processability in solution. The discrete molecular character and surface features of MOCs have a direct impact on the interactions between cages, enabling the final physical state of the materials to be tuned. In this tutorial review, we discuss how to use MOCs as core building units, highlighting the role played by surface functionalisation of MOCs in leading to porous materials in a range of states covering crystalline solids, soft matter, liquids and composites. We finish by providing an outlook on the opportunities for this work to serve as a foundation for the development of increasingly complex functional porous materials structured over various length scales. [ABSTRACT FROM AUTHOR]

Abstract: The effect of an external direct current (DC) electric field induction during hot-water treatment (HWT) on sol3gel derived ZnO coatings for controlled formation of good crystalline ZnO films was investigated. The electric field induced hot-water treatment (EF-HWT) was found to influence the formation of crystalline ZnO nanostructures on the ZnO gel films at low-temperature of 50°C for 3h. The effects of time, voltage and substrates used during the EF-HWT were investigated. Flower-like precipitates of hexagonal zinc oxide were generated from the zinc acetate derived ZnO gel film on a silicon single crystal substrate at the negative electrode by applying an electric field. Significant c-axis orientation of hexagonal ZnO on the silicon substrate was confirmed from XRD patterns. These results demonstrated that the EF-HWT of sol3gel derived ZnO films is a promising, low-temperature technique to control the morphology and crystallinity of oxide coatings. [Copyright &y& Elsevier]

Nanoporous carbon (NPC) is prepared by direct carbonization of Al-based porous coordination polymers (Al-PCP). By applying the appropriate carbonization temperature, both high surface area and large pore volume are realized for the first time. Our NPC shows much higher porosity than other carbon materials (such as activated carbons and mesoporous carbons). This new type of carbon material exhibits superior sensing capabilities toward toxic aromatic substances. [ABSTRACT FROM AUTHOR]

The design of crystal morphology, or exposed crystal facets, has enabled the development (e.g., catalytic activities, material attributes, and oriented film formation) of porous coordination polymers (PCPs) without changing material compositions. However, because crystal growth mechanisms are not fully understood, control of crystal morphology still remains challenging. Herein, we report the morphology design of [Cu3(btc)2]n (btc = benzene-1,3,5-tricarboxylate) by the coordination modulation method (modulator = n-dodecanoic acid or lauric acid). A morphological transition (octahedron-cuboctahedron-cube) in the [Cu3(btc)2]n crystal was observed with an increase in concentration of the modulator. By suitably defining a coarse-grained standard unit of [Cu3(btc)2]n as its cuboctahedron main pore and determining its attachment energy on crystal surfaces, Monte Carlo coarse-grain modeling revealed the population and orientation of carboxylates and elucidated an important role of the modulator in determining the 100- and 111-growth throughout the crystal growth process. This comprehension, in fact, successfully led to designed crystal morphologies with oriented growth on bare substrates. Because selective crystal orientations on the bare substrates were governed by crystal morphology, this contribution also casts a new light on the unexplored issue of the significance of morphology design of PCPs. [ABSTRACT FROM AUTHOR]

The article presents a study that examines the significance of yeast thioredoxin (TRX)-enriched extracts in mitigating the allogenicity of foods. It notes that treating the yeast RTX-enriched extracts and yeast thioredoxin reductase (NADPH) have enhanced the pepsin cleavage of β-lactoglobin and ovomucoid (OM). It adds that the treatment with TRX has significantly reduced the anaphylactic symptoms induced by OM, highlighting its benefits against food allergy.

A new strategy to synthesize monodispersed porous coordination polymer (PCP) nanocrystals at room temperature was developed and utilized for the formation of PCP thin films on gold substrates with fine control over the crystal sizes using the coordination modulation method. Hybridization of these PCP thin films with an environment-controlled quartz crystal microbalance system allowed determining the adsorption properties for organic vapors (methanol and hexane). In the case of high sensitivity (at the low-concentration dosing of analytes), the sensor response depended on the crystal size but not on the type of analyte. In contrast, at the high-concentration dosing, a clear dependence of the sorption kinetics on the analyte was observed due to significant sorbate-sorbate interaction. [ABSTRACT FROM AUTHOR]

Precise control of spin transition temperature (Tc) is one of the most important challenges in molecular magnetism. A Hofinann-type porous coordination polymer {Fe(pz)[PtII(CN)4]} (1; pz = pyrazine) exhibited cooperative spin transition near room temperature (TCUP = 304 K and Tcdown~ = 284 K) and its iodine adduct {Fe(pz)[PtII/IV(CN)4(I)]} (1~I), prepared by oxidative addition of iodine to the open metal sites of Pt , raised the Tc by 100 K. DSC and microscopic Raman spectra of a solid mixture of 1-I and 1 revealed that iodine migrated from 1-I to 1 through the grain boundary after heating above 398 K. We have succeeded in precisely controlling the iodine content of {Fe(pz)[Pt(CN)4(I)n]} (1-In; n = 0.0-1.0), which resulted in consecutive modulation of Tc in the range 300-400 K while maintaining the hysteresis width. Furthermore, it was demonstrated that iodine migration in the solid mixture was triggered by the spin transition of 1-I. The magnetically bistable porous framework decorating guest interactive open-metal-site in the pore surface makes it possible to modulate Tc ad arbitrium through unique postsynthetic method using iodine migration. [ABSTRACT FROM AUTHOR]

Introduction of porosity into supramolecular gels endows soft materials with functionalities for molecular encapsulation, release, separation and conversion. Metal‐organic polyhedra (MOPs), discrete coordination cages containing an internal cavity, have recently been employed as building blocks to construct polymeric gel networks with potential porosity. However, most of the materials can only be synthesized in organic solvents, and the examples of porous, MOP‐based hydrogels are scarce. Here, we demonstrate the fabrication of porous hydrogels based on [Rh2(OH‐bdc)2]12, a rhodium‐based MOP containing hydroxyl groups on its periphery (OH‐bdc=5‐hydroxy‐1,3‐benzenedicarboxylate). By simply deprotonating [Rh2(OH‐bdc)2]12 with the base NaOH, the supramolecular polymerization between MOPs and organic linkers can be induced in the aqueous solution, leading to the kinetically controllable formation of hydrogels with hierarchical colloidal networks. When heating the deprotonated MOP, Nax[Rh24(O‐bdc)x(OH‐bdc)24‐x], to induce gelation, the MOP was found to partially decompose, affecting the mechanical property of the resulting gels. By applying a post‐synthetic deprotonation strategy, we show that the deprotonation degree of the MOP can be altered after the gel formation without serious decomposition of the MOPs. Gas sorption measurements confirmed the permanent porosity of the corresponding aerogels obtained from these MOP‐based hydrogels, showing potentials for applications in gas sorption and catalysis. [ABSTRACT FROM AUTHOR]

In this paper, we describe the facile preparation of a chiral catalyst by the combination of the amino acid, L -proline (Pro), and the enzyme, porcine pancreas lipase (PPL), immobilized on a microporous metal–organic framework (PPL-Pro@MOF). The multipoint immobilization of PPL onto the MOF is made possible with the aid of Pro, which also provided a chiral environment for enhanced enantioselectivity. The application of the microporous MOF is pivotal in maintaining the catalytic activity of PPL, wherein it prevented the leaching of Pro during the catalytic reaction, leading to the enhanced activity of PPL. The prepared biocatalyst was applied in asymmetric carbon–carbon bond formation, demonstrating the potential of this simple approach for chemical transformations. [ABSTRACT FROM AUTHOR]

In this contribution, we present a coordination framework built from a novel (Zn4O)(O2C)6metaprismatic unit showing the interpenetration of a pair of enantiomorphic lcynets that exhibits commensurate sorption properties. [ABSTRACT FROM AUTHOR]

Reticular materials are of high interest for diverse applications, ranging from catalysis and separation to gas storage and drug delivery. These open, extended frameworks can be tailored to the intended application through crystal‐structure design. Implementing these materials in application settings, however, requires structuring beyond their lattices, to interface the functionality at the molecular level effectively with the macroscopic world. To overcome this barrier, efforts in expressing structural control across molecular, nano‐, meso‐, and bulk regimes is the essential next step. In this Review, we give an overview of recent advances in using self‐assembly as well as externally controlled tools to manufacture reticular materials over all the length scales. We predict that major research advances in deploying these two approaches will facilitate the use of reticular materials in addressing major needs of society. [ABSTRACT FROM AUTHOR]

Retikuläre Materialien sind von großem Interesse für Anwendungen in der Katalyse und Stofftrennung sowie der Gasspeicherung und gezielten Wirkstoffzufuhr. Diese offenporigen, ausgedehnten Gerüststrukturen können durch Kristallstrukturdesign auf spezifische Anwendungen zugeschnitten werden. Die Implementierung dieser Materialien in Anwendungsumgebungen erfordert jedoch eine Strukturierung über ihr Kristallgitter hinaus, um die Funktionalität auf molekularer Ebene effektiv mit der makroskopischen Welt zu verbinden. Um diese Barriere zu überwinden, werden als nächster Schritt Strategien für die Strukturierung retikulärer Materialien im Nano‐, Meso‐ und Volumenregime benötigt. In diesem Aufsatz geben wir einen Einblick in die jüngsten Fortschritte für die Herstellung von retikulären Materialien über allen Längenskalen, mit dem Fokus auf Selbstorganisationsstrategien und extern kontrollierten Ansätzen. Wir erwarten, dass bedeutende Forschungsfortschritte bei der Anwendung dieser beiden Ansätze in Verbindung mit retikulären Materialien erreicht werden und diese dabei helfen werden, wichtige Bedürfnisse der Gesellschaft zu bewältigen. [ABSTRACT FROM AUTHOR]

The discovery of NO, CO, and H2S as gasotransmitters and their beneficial role in multiple physiological functions opened an era of research devoted to exogenously delivering them as therapeutic agents. However, the gaseous nature of these molecules demands new forms of administration that enable one to control the location, dosage and timing of their delivery. Porous materials are among the most suitable scaffolds to store, deliver and release gasotransmitters due to their high surface area, tunable composition and reactivity. This review highlights the strategies employed to load and release gasotransmitters from different kinds of porous materials, including zeolites, mesoporous silica, metal–organic frameworks and protein assemblies. [ABSTRACT FROM AUTHOR]

Structural deformation in response to gas sorption is rarely observed for porous molecular solids, when compared to porous framework materials. Here, we describe the effect of chemical modification on the exterior of lantern-type metal–organic cages on the emergence and then disappearance of cooperative gas uptake. The results suggest that supramolecular design of ligands can be used to reveal this behaviour. [ABSTRACT FROM AUTHOR]

Zeolitic imidazolate frameworks (ZIFs) are a sub‐class of metal–organic frameworks (MOFs). Although generally stable, ZIFs can undergo post‐synthetic linker exchange (PSLE) in solution under mild conditions. Herein, we present a novel, solvent‐free approach to post‐synthetic linker exchange through exposure to linker vapor. [ABSTRACT FROM AUTHOR]

Zeolitic imidazolate frameworks (ZIFs) are a sub‐class of metal–organic frameworks (MOFs). Although generally stable, ZIFs can undergo post‐synthetic linker exchange (PSLE) in solution under mild conditions. Herein, we present a novel, solvent‐free approach to post‐synthetic linker exchange through exposure to linker vapor. [ABSTRACT FROM AUTHOR]

Porous molecular cages have a characteristic processability arising from their solubility, which allows their incorporation into porous materials. Attaining solubility often requires covalently bound functional groups that are unnecessary for porosity and which ultimately occupy free volume in the materials, decreasing their surface areas. Here, a method is described that takes advantage of the coordination bonds in metal–organic polyhedra (MOPs) to render insoluble MOPs soluble by reversibly attaching an alkyl‐functionalized ligand. We then use the newly soluble MOPs as monomers for supramolecular polymerization reactions, obtaining permanently porous, amorphous polymers with the shape of colloids and gels, which display increased gas uptake in comparison with materials made with covalently functionalized MOPs. [ABSTRACT FROM AUTHOR]

Porous molecular cages have a characteristic processability arising from their solubility, which allows their incorporation into porous materials. Attaining solubility often requires covalently bound functional groups that are unnecessary for porosity and which ultimately occupy free volume in the materials, decreasing their surface areas. Here, a method is described that takes advantage of the coordination bonds in metal–organic polyhedra (MOPs) to render insoluble MOPs soluble by reversibly attaching an alkyl‐functionalized ligand. We then use the newly soluble MOPs as monomers for supramolecular polymerization reactions, obtaining permanently porous, amorphous polymers with the shape of colloids and gels, which display increased gas uptake in comparison with materials made with covalently functionalized MOPs. [ABSTRACT FROM AUTHOR]

The ability to control the structure and topology of polymer networks, both on macroscopic and molecular levels, is crucial for optimizing their performance. Here we describe a novel type of network polymer, which is synthesized via conversion of a highly ordered metal-organic framework (MOF) template into a polymer gel. The synthesis is performed using light-induced and metal-free thiol-ene click chemistry. The use of light-triggered reactions in combination with photomasks or other photopatterning techniques allows the reaction to be locally confined and thereby structuring the network polymer on a macroscopic level. The potential to vary and exactly adjust the parameters within the polymer network (including exact network topology on the nanometer scale as well as the macroscopic morphology) combined with the ability to further functionalize their surfaces or incorporate guest molecules allows their targeted design for potential applications in catalysis and optoelectronics as well as their use as a novel biomaterial. [ABSTRACT FROM AUTHOR]

During bread-making processes, yeast cells are exposed to baking-associated stresses such as freeze-thaw, air-drying, and high-sucrose concentrations. Previously, we reported that self-cloning diploid baker's yeast strains that accumulate proline retained higher-level fermentation abilities in both frozen and sweet doughs than the wild-type strain. Although self-cloning yeasts do not have to be treated as genetically modified yeasts, the conventional methods for breeding baker's yeasts are more acceptable to consumers than the use of self-cloning yeasts. In this study, we isolated mutants resistant to the proline analogue azetidine-2-carboxylate (AZC) derived from diploid baker's yeast of Saccharomyces cerevisiae . Some of the mutants accumulated a greater amount of intracellular proline, and among them, 5 mutants showed higher cell viability than that observed in the parent wild-type strain under freezing or high-sucrose stress conditions. Two of them carried novel mutations in the PRO1 gene encoding the Pro247Ser or Glu415Lys variant of γ-glutamyl kinase (GK), which is a key enzyme in proline biosynthesis in S. cerevisiae . Interestingly, we found that these mutations resulted in AZC resistance of yeast cells and desensitization to proline feedback inhibition of GK, leading to intracellular proline accumulation. Moreover, baker's yeast cells expressing the PRO1 P247S and PRO1 E415K gene were more tolerant to freezing stress than cells expressing the wild-type PRO1 gene. The approach described here could be a practical method for the breeding of proline-accumulating baker's yeasts with higher tolerance to baking-associated stresses. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks are a unique class of materials well known for their crystallinity and ultra-high porosity. Since their first report over fifteen years ago, research in this area has sought to actively exploit these properties, especially in gas adsorption. In this article we canvass some emerging topics in the field of MOF research that show promise for new applications in areas such as biotechnology, catalysis, and microelectronics. [ABSTRACT FROM AUTHOR]

The application of metal–organic frameworks (MOFs) for gas storage, molecular separations and catalysis necessitates careful consideration of the particle size and structuralisation (e.g. pelletisation, surface-anchoring) of a material. Recently, particle size has been shown to dramatically alter the physical and structural properties of certain MOFs, but overall there is limited information on how the particle size affects the properties of flexible MOFs. Here we demonstrate that the particle size of a flexible MOF, specifically the as-synthesised form of [Cu(bcppm)H2O]·S (H2bcppm = bis(4-(4-carboxyphenyl)-1H-pyrazolyl)methane, S = solvent) (1), correlates with the rate of structural reorganisation from a “kinetically-trapped”, activated 3D form of this MOF to an “open” 2D form of the structure. We also outline two methods for synthetically reducing the particle size of 1 at room temperature, using 0.1 M NaOH (for two reaction times: 0.5 and 16 h) and with the sodium salt of the ligand Na2bcppm, producing crystals of 85 ± 15, 280 ± 14 and 402 ± 41 nm, respectively. [ABSTRACT FROM AUTHOR]

Composites based on Metal-Organic Frameworks (MOFs) are an emerging class of porous materials that have been shown to possess unique functional properties. Nanoparticles@MOFs composites combine the tailorable porosity of MOFs with the versatile functionality of metal or metaloxide nanoparticles. A wide range of nanoparticles@MOFs have been synthesised and their performance characteristics assessed in molecular adsorption and separation, catalysis, sensing, optics, sequestration of pollutants, drug delivery, and renewable energy. This review covers the main research areas where nanoparticles@MOFs have been strategically applied and highlights the scientific challenges to be considered for their continuing development. [ABSTRACT FROM AUTHOR]

The synthesis of highly crystalline macro-meso-microporous monolithic Cu3(btc)2 (HKUST-1; btc3− = benzene-1,3,5-tricarboxylate) is demonstrated by direct conversion of Cu(OH)2-based monoliths while preserving the characteristic macroporous structure. The high mechanical strength of the monoliths is promising for possible applications to continuous flow reactors. [ABSTRACT FROM AUTHOR]

[Display omitted] • Defined coordination cages (CCs) with metal-pyridine coordination bonds. • Defined metal-organic cages (MOCs) bearing tetracarboxylates paddlewheel complexes. • Meta-analyzed experimental information of 197 CCs and 83 MOCs. • Unveiled roles of ligand, metal ion, temperature and solvent for cage formation. • Discussed challenges and future perspectives of CCs and MOCs in unexplored areas. Cage-like molecules, assembled by the coordination of multiple metal ions and organic links, are pushing new frontiers in science due to their design flexibility and the resulting diverse and unique chemical properties. This field has been advanced by two close but distinct chemistry communities. Consequently, the family of molecules referred to as coordination cages (CCs) constituted of metal-pyridine coordination bonds or metal–organic cages (MOCs) based on dinuclear tetracarboxylates paddlewheel complexes in each community had not been reviewed cross-sectionally, even though they are conceptually similar. This review article extracted and compared experimental information on a total of 197 CCs and 83 MOCs from 185 reports to identify their synthetic and structural signatures. We did not merely enumerate the reports we collected; we meta-analyzed the data extracted from the reports and highlighted both the similarities and dissimilarities between CCs and MOCs. As a result, we clarified the key parameters governing the synthetic conditions. Furthermore, we identified a new research direction by visualizing unexplored features and properties of CCs and MOCs. This review article provides a good tutorial both for researchers attempting to cross the boundary between CCs and MOCs and those who are new to the field. [ABSTRACT FROM AUTHOR]

In this study, we selected 181 nematode glycogenes that are orthologous to human glycogenes and examined their RNAi phenotypes. The results are deposited in the Caenorhabditis elegans Glycogene Database (CGGDB) at AIST, Tsukuba, Japan. The most prominent RNAi phenotypes observed are disruptions of cell cycle progression in germline mitosis/meiosis and in early embryonic cell mitosis. Along with the previously reported roles of chondroitin proteoglycans, glycosphingolipids and GPI-anchored proteins in cell cycle progression, we show for the first time that the inhibition of the functions of N-glycan synthesis genes (cytoplasmic alg genes) resulted in abnormal germline formation, ER stress and small body size phenotypes. The results provide additional information on the roles of glycoconjugates in the cell cycle progression mechanisms of germline and embryonic cells. [ABSTRACT FROM PUBLISHER]

We demonstrate a new approach to superhydrophobic porous coordination polymers by incorporating an anisotropic crystal morphology featuring a predominant surface that is highly corrugated and terminated by aromatic hydrocarbon moieties. The resulting low-energy surface provides particularly promising hydrophobic properties without the need for postsynthetic modifications or surface processing that would block the porosity of the framework. Consequently, hydrophobic organic molecules and water vapor are able to penetrate the surface and be densely accommodated within the pores, whereas bulk water is repelled as a result of the exterior surface corrugation derived from the aromatic surface groups. This study provides a new strategy for the design and development of superhydrophobic porous materials. [ABSTRACT FROM AUTHOR]

We demonstrate a new approach to superhydrophobic porous coordination polymers by incorporating an anisotropic crystal morphology featuring a predominant surface that is highly corrugated and terminated by aromatic hydrocarbon moieties. The resulting low-energy surface provides particularly promising hydrophobic properties without the need for postsynthetic modifications or surface processing that would block the porosity of the framework. Consequently, hydrophobic organic molecules and water vapor are able to penetrate the surface and be densely accommodated within the pores, whereas bulk water is repelled as a result of the exterior surface corrugation derived from the aromatic surface groups. This study provides a new strategy for the design and development of superhydrophobic porous materials. [ABSTRACT FROM AUTHOR]

A critical materials challenge over the next quarter century is the sustainable use and management of the world’s natural resources, particularly the scarcest of them. Chemistry’s ability to get more from less is epitomized by porous coordination polymers, also known as metal–organic frameworks (MOFs), which use a minimum amount of material to build maximum surface areas with fine control over pore size. Their large specific surface area and tunable porosity make MOFs useful for applications including small-molecule sensing, separation, catalysis, and storage and release of molecules of interest. Proof-of-concept projects have demonstrated their potential for environmental applications such as carbon separation and capture, water purification, carcinogen sequestration, byproduct separation, and resource recovery. To translate these from the laboratory into devices for actual use, however, will require synthesis of MOFs with new functionality and structure. [ABSTRACT FROM AUTHOR]