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A highly flexible and nonflammable inorganic hydroxyapatite (HAP) paper made from HAP ultralong nanowires is reported. The paper can be used for printing and writing and is promising for the permanent and safe storage of information, such as archives and important documents. The HAP paper is also an excellent and recyclable adsorbent for organic pollutants. [ABSTRACT FROM AUTHOR]

Molecular catalysts have been shown to have high selectivity for CO2 electrochemical reduction to CO, but with current densities significantly below those obtained with solid‐state materials. By depositing a simple Fe porphyrin mixed with carbon black onto a carbon paper support, it was possible to obtain a catalytic material that could be used in a flow cell for fast and selective conversion of CO2 to CO. At neutral pH (7.3) a current density as high as 83.7 mA cm−2 was obtained with a CO selectivity close to 98 %. In basic solution (pH 14), a current density of 27 mA cm−2 was maintained for 24 h with 99.7 % selectivity for CO at only 50 mV overpotential, leading to a record energy efficiency of 71 %. In addition, a current density for CO production as high as 152 mA cm−2 (>98 % selectivity) was obtained at a low overpotential of 470 mV, outperforming state‐of‐the‐art noble metal based catalysts. [ABSTRACT FROM AUTHOR]

Synthesis of diverse sterically congested molecules from a single important intermediate is one of the ideal synthetic strategies in organic synthesis. In this paper, we found that γ‐oxoalkyl substituted cyclohexenone derivatives (OAC) possessing a quaternary carbon are a useful key intermediate to derive both congested fused [5,6] rings and spirocycles. For this purpose, we have established an efficient synthetic method to obtain OAC by tertiary alkylation of β‐methylcyclohexenone derivatives using α‐bromocarbonyl compounds as a tertiary alkyl source. The key to the success of this reaction is controlling the reactivity of the dienamine intermediate. While there have been many reports on enamine reactions, dienamine reactions have not been well studied. Herein, we report controlling reactivity of dienamines and molecular diversification from OAC. [ABSTRACT FROM AUTHOR]

This paper presents a one‐step photochemical method for the preparation of CdS/Poly(MMA‐co‐MAA) composite photocatalyst, based on the concept of simultaneous photocatalytic polymerization of organic monomers during UV‐light induced formation of CdS. The preparation is carried out in an aqueous solution of Na2S2O3, CdSO4, methyl methacrylate (MMA) and methacrylic acid (MAA), under a UV lamp. The continuously formed CdS particles with photocatalytic activity act the role of initiator to directly initiate the copolymerization of MMA and MAA, resulting in the in situ formation of the composite and full contact of the CdS particles with the oxygen‐containing groups in the polymer. Taking the photocatalytic degradation of methylene blue as a case study, the composite exhibited significantly higher activity under simulated solar light compared to the pure CdS. By analysis on various data, the enhanced photocatalytic activity is attributed to the enhanced visible light absorption, and especially the high electron‐hole separation efficiency caused by the electrostatic interaction between photogenerated holes and carbonyl oxygen atoms with negatively charged features. Furthermore, the composite displays excellent sunlight activity and recyclability, suggesting its potential for practical applications. Such a one‐step construction strategy relying only on photo‐energy is green, low‐cost and promising in obtaining high‐performance semiconductor/polymer composite photocatalysts. [ABSTRACT FROM AUTHOR]

Hydrogen‐bonded organic frameworks (HOFs) are a class of crystalline framework materials assembled by hydrogen bonds. HOFs have the advantages of high crystallinity, mild reaction conditions, good solution processability, and reproducibility. Coupled with the reversibility and flexibility of hydrogen bonds, HOFs can be assembled into a wide diversity of crystalline structures. Since the bonding energy of hydrogen bonds is lower than that of ligand and covalent bonds, the framework of HOFs is prone to collapse after desolventisation and the stability is not high, which limits the development and application of HOFs. In recent years, numerous stable and functional HOFs have been developed by π–π stacking, highly interpenetrated networks, charge‐assisted, ligand‐bond‐assisted, molecular weaving, and covalent cross‐linking. Charge‐assisted ionic HOFs introduce electrostatic attraction into HOFs to improve stability while enriching structural diversity and functionality. In this paper, we review the development, the principles of rational design and assembly of charge‐assisted ionic HOFs, and introduces the different building block construction modes of charge‐assisted ionic HOFs. Highlight the applications of charge‐assisted ionic HOFs in gas adsorption and separation, proton conduction, biological applications, etc., and prospects for the diverse design of charge‐assisted ionic HOFs structures and multifunctional applications. [ABSTRACT FROM AUTHOR]

This article introduces a special collection of papers dedicated to Maurizio Prato, a renowned scientist in the field of carbon nanostructures and molecular nanoscience. The collection showcases Prato's team's achievements in integrating complex frontier research with groundbreaking advancements in these fields. Prato's work focuses on designing and synthesizing carbon nanostructures for applications in regenerative medicine and solar energy research. The article highlights Prato's scientific journey, his contributions to sustainable materials, and his impact on shaping functional nano-interfaces through precision chemistry. The Prato lab has made significant contributions to nanotechnology, particularly in the area of functionalized carbon nanotubes (f-CNT). Their research has shown that f-CNT are more biocompatible and easily cleared from the body compared to nonfunctionalized CNT. The lab has applied this knowledge to develop solutions for challenging problems such as healing spinal cord injuries and using water as a solar fuel. Their work in regenerative medicine has shown promising results in repairing severe and irreversible nervous system lesions, while their research in energy conversion has explored the use of f-CNT for solar energy conversion. Maurizio Prato, the leader of the lab, has fostered an interdisciplinary and collaborative environment, encouraging his team to explore diverse research avenues and promoting intellectual freedom. His mentorship and open-mindedness have been instrumental in the lab's success. [Extracted from the article]

Distyrylbenzenes (DSBs) are well‐known for their strong multicolour fluorescence. Fluorescence tuning of DSB via further functionalization/arylation, on the other hand, is uncommon. This paper reports a Pd‐catalysed direct arylation approach for introducing different aryl groups onto fluorobenzene‐containing DSB moiety (7) in high yields (67–72 %). The versatile methodology allows the substitution of neutral [tolyl (1)], electron‐deficient [p‐formyl benzene (2), p‐acetyl benzene (3), p‐nitrobenzene (4)] and electron‐rich [carbazole (5), triphenylamine (6)] aryl groups. The electron‐deficient aryls render mono‐substitution, while the electron‐rich counterparts promote di‐substitution. The compounds (1–6) show blue, green, and yellow fluorescence in both the solution and solid states; the fluorescence quantum yields reach >98 % and the peak maxima span from 425 to 560 nm. The mono‐carbazole DSB (5) exhibit white light emission (WLM) in polar solvents (acetone, DMF, CH3CN, DMSO and NMP) with very high fluorescence quantum yields (φf) of 60–80 %. For WLM, such high efficiency (φf) is somewhat uncommon. Moreover, visible‐to‐NIR reversible electrochromism is demonstrated by the TPA‐integrated DSB (6). The colour of 6 changes from pristine light yellow to orange, and the absorption maxima shifts from 372 to 1500 nm when a positive potential of 1.0 V vs Ag/Ag+ is applied. Moreover, the system shows high colouration efficiency in the NIR region with fast switching speeds for colouration and decolouration as fast as 0.98 s and 1.05 s. [ABSTRACT FROM AUTHOR]

Among many problems of a fundamental value in the heteroatom chemistry the mechanism and stereochemistry of the nucleophilic substitution reaction at the phosphorus and other heteroatom centres have attracted great attention of phosphorus chemists already in the middle of the last century. This review, which does not have a comprehensive character, summarizes the selected original contributions aimed at solution of the mechanism of SN2−P reaction and its relationship with stereochemistry. The breakthrough in these studies was the Westheimer's concept and his rules which is presented at the beginning of this article. Next, a series of papers is presented where the stereochemistry of the substitution at phosphorus was investigated in cyclic five‐, four‐ and six‐membered ring phosphorus compound. The majority of these reactions have been found to occur with retention of the P‐configuration. In the third part of this account, the selected examples of substitution reactions at phosphorus in acyclic compounds are discussed. As the results of all the investigations discussed did not allow to undoubtedly ascribe the mechanism (SN2 or A−E) to the investigated reactions, in the last part the SN‐P reactions are presented, the mechanism of which has been established by combination of the stereochemical and DFT‐studies. [ABSTRACT FROM AUTHOR]

Fluorescent polymeric materials have been exploited in the fields of aesthetical purposes, biomedical engineering, and three‐dimensional printing applications. While the fluorescent materials are prepared by the polymerization of fluorescent monomer or the blending a fluorescent dye with common polymer, the covalent immobilization of fluorescent dye onto common polymers is not the practical technique. In this paper, dansylated nitrile N‐oxide (Dansyl‐NO) has been designed and synthesized to be a stable nitrile N‐oxide as the derivative of 2‐hydroxy‐1‐naphthaldehyde. While Dansyl‐NO shows good reactivity to an alkene and an alkyne to give fluorescent Dansyl‐Ene and Dansyl‐Yne, respectively, it hardly reacts to a nitrile. The results indicate that Dansyl‐NO serves as a fluorescent dye clickable to alkenes and alkynes. To know the effects of solvent on the fluorescent properties, the UV‐vis and fluorescence spectra of Dansyl‐Ene are measured in three solvents. Dansyl‐Ene shows fluorescent solvatochromism, which appears to be red‐shifted along with the increase in solvent polarity. Poly(styrene‐co‐butadiene) directly reacts with Dansyl‐NO to give fluorescent modified SB. The emission spectrum of modified SB is blue‐shifted compared with that of Dansyl‐Ene. The blue‐shift could be possibly attributed to the presence of less polar polymer skeleton around the dansyl moieties of modified SB. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) are a class of porous crystalline polymeric materials constructed by linking organic small molecules through covalent bonds. COFs have the advantages of strong covalent bond network, adjustable pore structure, large specific surface area and excellent thermal stability, and have broad application prospects in various fields. Based on these advantages, rational COFs design strategies such as the introduction of active sites, construction of conjugated structures, and carbon material composite, etc. can effectively improve the conductivity and stability of the electrode materials in the field of batteries. This paper introduces the latest research results of high‐performance COFs electrode materials in alkali metal‐ion batteries (LIBs, SIBs, PIBs and LSBs) and other advanced batteries. The current challenges and future design directions of COFs‐based electrode are discussed. It provides useful insights for the design of novel COFs structures and the development of high‐performance alkali metal‐ion batteries. [ABSTRACT FROM AUTHOR]

Bubbles arising from wild gas evolution commonly exist in electrochemical systems, particularly in water electrolysis and rechargeable aqueous batteries (e. g. Zn‐air batteries). Substantial energy dissipation occurs due to the obstruction of active sites and ion‐conducting pathways by evolving bubbles. Efforts are made to elucidate effective strategies for fast gas transport, most of which focus on minimizing bubble size and facilitating their timely detachment through complex techniques such as constructing super‐hydrophilic nano‐structure electrodes, flowing electrolytes, and ultrasonic oscillation. Recently, an innovative, facile, and highly efficient method utilizing a breathable electrode design to promote gaseous molecules to the external environment emerges as a promising approach since it avoids remarkable bubble accumulation while remaining free of additional accessories. This paper highlights the origin and evolution of this promising design. Starting with introducing the basic concept of traditional breathable electrodes based on hydrophobic polymer networks and discussing the current progress made in underlying mechanisms, a detailed description of the advanced design inspired by a "bubble‐diode" concept with superior breathability follows. This Concept aims to contribute to a deep understanding of this technology and paves the way for further advancements in this renewable energy era. [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]

The selective synthesis of cage‐type hydrocarbons through the editing of the highly symmetric molecule cubane can be anticipated as one of the efficient approaches. In this paper, we identify a catalyst that facilitates the efficient scaffold isomerization of cubanes into homocubanes. This approach, which involves the direct synthesis of homocubanol esters, is promising as a novel method for the synthesis of phenoxy bioisosteres. Additionally, we observed that the isomerization of 1,4‐bis(acyloxymethl)cubane results in the generation of both D2‐ and C2‐symmetrical bishomocubanes. The same catalyst was also applied to the isomerization of acyloxymethylcuneanes, producing homocuneanol esters. [ABSTRACT FROM AUTHOR]

The paper presents the colloidal and thermal stability of the three‐component hybrid materials containing halloysite, polysaccharides (alginic acid, cationic cellulose and hydroxyethyl cellulose) and Tritons. TX‐100, TX‐165 and TX‐405 were used as non‐ionic surfactants. Stability and other properties of the hybrid materials were tested by the following methods: UV–Vis, TGA (thermogravimetric analysis) and DSC (differential scanning calorimetry), CHN (elemental analysis), SEM‐EDX (scanning electron microscopy with energy dispersive X‐ray spectroscopy) and tensiometry. According to the results with the increasing polymer concentration the colloidal stability of the tested systems also increases. Moreover, the addition of the surfactants causes the increase of polysaccharide adsorption but the colloidal stability of the tested systems decreases due to large weights of formed aggregates. As follows from the thermal analysis, the comparison of the TG/DTG‐DSC curves obtained for the investigated polymers confirms that their thermal decomposition courses have some common features. The obtained results have the application potential in the formation of the materials for the pollutants removal from water and sewages. [ABSTRACT FROM AUTHOR]

Worldwide lithium demand has surged in recent years due to increased production of Li‐ion batteries for electric vehicles and stationary storage. Li supply and production will need to increase such that the transition towards increased electrification in the energy sector does not become cost prohibitive. Many countries have taken policy steps such as listing Li as a critical mineral. Current commercial Li mining is mostly from dedicated mine sources, including ores, clays, and brines. The conventional ways to extract Li+ from those resources are through chemical processing and includes steps of calcination, leaching, precipitation, and purification. The environmental and economic sustainability of conventional Li processing has recently received increased scrutiny. Routes such as direct Li+ extraction may provide advantages relative to conventional Li+ extraction technologies, and one possible route to direct Li+ extraction includes leveraging intercalation materials. Intercalation material processing has recently demonstrated high selectivity towards Li+ as opposed to other cations. Reviews and reports of direct Li+ extraction with intercalation materials are limited, even as this technology has started to show promise in smaller‐scale demonstrations. This paper will review selective Li+ extraction via intercalation materials, including both electrochemical and chemical methods to drive Li+ in and out, and efforts to characterize the Li+ insertion/deinsertion processes. [ABSTRACT FROM AUTHOR]

The tremendous importance of dirhodium paddlewheel complexes for asymmetric catalysis is largely the result of an empirical optimization of the chiral ligand sphere about the bimetallic core. It was only recently that a H(C)Rh triple resonance 103Rh NMR experiment provided the long‐awaited opportunity to examine – with previously inconceivable accuracy – how variation of the ligands impacts on the electronic structure of such catalysts. The recorded effects are dramatic: formal replacement of only one out of eight O‐atoms surrounding the metal centers in a dirhodium tetracarboxylate by an N‐atom results in a shielding of the corresponding Rh‐site of no less than 1000 ppm. The current paper provides the theoretical framework that allows this and related experimental observations made with a set of 19 representative rhodium complexes to be interpreted. In line with symmetry considerations, it is shown that the shielding tensor responds only to the donor ability of the equatorial ligands along the perpendicular principal axis. Axial ligands, in contrast, have no direct effect on shielding but may come into play via the electronic cis ${cis}$ ‐effect that they exert onto the neighboring equatorial sites. On top of these fundamental interactions, charge redistribution within the core as well as the electronic trans ${trans}$ ‐effect of ligands of different donor strengths is reflected in the recorded 103Rh NMR shifts. [ABSTRACT FROM AUTHOR]

Biohybrid catalysts that operate in aqueous media are intriguing for systems chemistry. In this paper, we investigate whether control over the self‐assembly of biohybrid catalysts can tune their properties. As a model, we use the catalytic activity of functional hybrid molecules consisting of a catalytic H‐dPro‐Pro‐Glu tripeptide, derivatized with fatty acid and nucleobase moieties. This combination of simple biological components merged the catalytic properties of the peptide with the self‐assembly of the lipid, and the structural ordering of the nucleobases. The biomolecule hybrids self‐assemble in aqueous media into fibrillar assemblies and catalyze the reaction between butanal and nitrostyrene. The interactions between the nucleobases enhanced the order of the supramolecular structures and affected their catalytic activity and stereoselectivity. The results point to the significant control and ordering that nucleobases can provide in the self‐assembly of biologically inspired supramolecular catalysts. [ABSTRACT FROM AUTHOR]

In pKa computational determination, the challenge in exploring and fostering new methodologies and approaches goes in parallel with the amelioration of computational performances. In this paper a "ready to use methodology" has been compared to other strategies, such as the re‐shaping in solvation cavity (Bondi radius re‐shaping), wanting to assess its reliability in predicting the pKa of a broad list of carboxylic acids. Thus, the functionals B3LYP and CAM‐B3LYP have been selected, using SMD as continuum solvation model. Exploiting our previous results, two water molecules were made explicit on the reaction centre. Data show that our model (CAM‐B3LYP/2H2O) is capable to accurately predict pKa, leading to mean absolute error (MAE) values lower than 0.5. Noteworthy, good results were achieved in computing the pKa of substituents bearing nitro and cyano groups. Focusing on B3LYP, eventually remarkable outputs were obtained only when Bondi correction was applied to the complex with two water molecules. Hence, massive outcomes were obtained in foreseeing the trichloro and trifluoro acetic acid pKa. These findings demonstrated that no complex level of theory nor external factor is required to accurately predict carboxylic acids pKa, with MAE well below 0.5 units. [ABSTRACT FROM AUTHOR]

1,2‐benzisothiazol‐3(2H)‐one derivatives are highly active against a broad spectrum of fungi as well as Gram positive and Gram negative bacteria. For this reason they are extensively used, for example, as additives in detergents, leather products, paper coatings, and antifouling paintings. In this paper experimental findings are reported proving that the sulfur atom of benzisothiazolinones have a remarkable tendency to form short and directional chalcogen bondings on the extension of the covalent N−S bond and, to a lesser extent, of the C−S bond. Analyses of the Cambridge Structural Database confirm the interaction as a primary recognition motif of these systems. The electrophilicity of sulfur is crucial in the chemical reactions initiating the cascade of events resulting in the biopharmacological activities of benzisothiazolinones. The reported results suggest that the electrophility of sulfur may play a role also at earlier stages than the reactive ones, namely it may pin the compounds at the active site of target enzymes via chalcogen bondings that preorganize the system in the conformation required for the bonds formation/cleavage determining the biopharmacological activity [ABSTRACT FROM AUTHOR]

Chemists have long sought to regulate the reactivity of H2, to yield hydride ions, hydrogen atoms, or electrons on demand. One source of inspiration for achieving this control is [NiFe]hydrogenase ([NiFe]H2ase), which reacts with H2 to form various hydrogen active species such as NiIII hydride species, NiII hydride species, and NiI low‐valent species. Chemists have attempted to synthesize these hydrogen active species not only as models for the active species of [NiFe]H2ase, but also as electron transfer catalysts. However, the synthesis of NiI complex directly from H2 has not been reported. This paper reports the first example of a single‐step synthesis of a NiI complex, via reaction of a NiII complex with H2, stable for over 3 months at room temperature and we further demonstrate a reductive coupling of acridinium ions as part of a reaction cycle. [ABSTRACT FROM AUTHOR]

Stimulus‐responsive organic materials with luminescence switching properties have attracted considerable attention for their practical applications in sensing, security, and display devices. In this paper, bent‐type bisbenzofuropyrazine derivatives, Bent‐H and Bent‐sBu, with good solubilities were synthesized, and their physical and optical properties were investigated in detail. Bent‐H gave three crystalline polymorphs, and they showed different luminescence properties depending on their crystal packing structures. In addition, Bent‐H exhibited mechanochromic luminescence in spite of its rigid skeleton. Bent‐sBu exhibited unique concentration‐dependent vapochromic luminescence. Ground Bent‐sBu was converted to blue‐emissive, green‐emissive, and green‐emissive high‐viscosity solution states at low, moderate, and high concentrations of CHCl3 vapor, respectively. This finding represents a concentration‐dependent multi‐phase transition with an organic solvent, which is of potent interest for application in sensing systems. [ABSTRACT FROM AUTHOR]

Chiral macrocycles with circularly polarized luminescence (CPL) have attracted increasing attention due to the rigid structure, symmetrical chiral geometry and large luminescence dissymmetry factors (glum). However, most chiral macrocycles are more emissive in solutions but have weakened fluorescence quantum yields (ΦF) in aggregates, limiting their further application. In this paper, chiral macrocycle R/S‐PhTPE was synthesized by combining chiral macrocycle architectonics with Z‐o‐phenyltetraphenylethylene (PhTPE) foldamer. Enhanced solution state emission and characteristic aggregation enhanced emission (AEE) effect can be observed for R/S‐PhTPE due to the folded PhTPE conformation. Macrocycle immobilization and folded conformation endow PhTPE moiety with stable helical conformation. Most importantly, R/S‐PhTPE exhibits opposite CPL signals compared with common chiral TPEs, demonstrating the evident impact of folded conformation. This work reports the first and deep insights into the chiroptical properties of chiral PhTPE foldamers, and will provide a new strategy to tune ΦF and CPL signals of AIE active chiral macrocycles. [ABSTRACT FROM AUTHOR]

The surprising differences between the experimental solid‐state and calculated gas‐phase structures of 5‐oxo‐1,3,2,4‐dithiadiazole (Roesky's ketone, 1) and 1‐oxo‐1,2,4,3,5‐trithiadiazole (Roesky's sulfoxide, 2), identified and studied in a series of papers published between 2004 and 2010 but then never satisfactorily explained, have been revisited, making use of the more advanced computational possibilities currently available. The previous calculations' considerable overestimations of the C−S and S−S bond lengths in 1 and 2, respectively, have been partly explained based on the results of periodic calculations and the application of Valence Bond (VB) Theory. In the case of 1, the crystal environment appears to stabilize a structure with a highly polarized C=O bond, which features a C−S bond with considerable double‐bond character – an effect which does not exist for the isolated molecule – explaining the much shorter bond in the solid state. For 2, a similar conclusion can be drawn for the S−S distance. For both compounds, though, packing effects are not the sole source of the differences: the inability of Density Functional Theory (DFT) to properly deal with the electronic structures of these apparently simple main‐group systems remains a contributing factor. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) smaller than 10 nm constitute a new type of fluorescent carbon‐based nanomaterial. They have attracted much attention owing to their unique structures and excellent photoelectric properties. Primitive CDs usually comprise carbon and oxygen and are synthesized in one step from various natural products or synthetic organic compounds, usually via microwave or hydrothermal methods. However, the uniformity of surface functional groups often make CDs lack the diversity of active sites required for specific applications. Therefore, the functionalization of CDs by specific groups is a powerful strategy for improving their photophysical and photochemical properties. This paper reviews surface modification strategies to overcome these shortcomings. Functionalizing CDs using covalent or non‐covalent modification can give them unique properties and broaden their applicability. [ABSTRACT FROM AUTHOR]

The addition of heteroatom compounds to alkynes and alkenes is an atom‐efficient method of carbon‐heteroatom bond formation and is widely used as a fundamental synthetic method for the construction of functional molecules. Nevertheless, examples of transition‐metal‐catalyzed addition reactions of group 16 heteroatom compounds to carbon‐carbon unsaturated bonds have been limited due to the widespread belief that organic sulfur and selenium compounds are representative catalyst poisons. In recent decades, however, several seminal catalytic reactions of sulfur compounds have been developed, providing important insights into catalysis and poisons. Therefore, this paper focuses on the transition‐metal‐catalyzed addition of organosulfur compounds to alkynes and alkenes, gains comprehensive insights into the catalysis and catalyst poisons, and proposes concepts for the development of transition‐metal‐catalyzed reactions of group 16 heteroatom compounds. [ABSTRACT FROM AUTHOR]

Inkless and erasable printing (IEP) based on chromic materials holds great promise to alleviate environmental and sustainable problems. Metal–organic polymers (MOPs) are bright platforms for constructing IEP materials. However, it is still challenging to design target MOPs with excellent specific functions rationally due to the intricate component‐structure‐property relationships. Herein, an effective strategy was proposed for the rational design IEP‐MOP materials. The stimuli‐responsive viologen moiety was introduced into the construction of MOPs to give it potential chromic behaviors and two different coordination models (i. e. bilateral coordination model, M1; unilateral coordinated model, M2) based on the same viologen ligand were designed. Aided by theoretical calculations, model M1 was recommended secondarily as a more suitable system for IEP materials. Along this line, two representative viologen‐ZnII MOPs 1 and 2 with models M1 and M2 were synthesized successfully. Experiments exhibit that 1 does have quicker stimuli response, stronger color contrast and longer radical lifetime compared to 2. Significantly, the obtained 1‐IEP media brightly inherits the excellent chromic characteristics of 1 and the flexibility of the paper at the same time, which achieves most daily printing requirements, as well as enough resolution and durability to be used in identification by smart device. [ABSTRACT FROM AUTHOR]

A novel electrochemically assisted cycloaddition process is proposed, in which highly efficient coupling of CO2 with styrene oxide (SO) can be achieved to form styrene carbonate (SC) as a high‐value‐added product. A series of Cu catalysts with different morphologies and chemical states were fabricated on carbon paper (CP) by using in‐situ electrodeposition, and the sample with nano‐dendrimer structure was found to exhibit a relatively high activity of 74.8 % SC yield with 92.7 % SO conversion under gentle reaction conditions, thus showing its potential for practical applications. The relatively high electrochemically active surface area and charge transfer ability of dendrimer‐like Cu benefited the electrochemical reaction. In particular, the Cu2+ species that were formed in situ during the reaction played a vital role in enhancing the activity and selectivity of the proposed Cu/CP hybrid catalyst. Cu2+ atoms served as active sites that can not only electrochemically activate CO2 but also facilitate the ring opening of SO. Mechanistic analysis suggested that the reaction followed electrochemical and liquid‐phase heterogeneous paths, which provide a new green and sustainable route for efficient utilization of CO2 resources for fine chemical electrosynthesis. [ABSTRACT FROM AUTHOR]

A simple, cost‐effective strategy was developed to effectively improve the electron transfer efficiency as well as the power output of microbial fuel cells (MFCs) by decorating the commercial carbon paper (CP) anode with an advanced Mo2C/reduced graphene oxide (Mo2C/RGO) composite. Benefiting from the synergistic effects of the superior electrocatalytic activity of Mo2C, the high surface area, and prominent conductivity of RGO, the MFC equipped with this Mo2C/RGO composite yielded a remarkable output power density of 1747±37.6 mW m−2, which was considerably higher than that of CP‐MFC (926.8±6.3 mW m−2). Importantly, the composite also facilitated the formation of 3D hybrid biofilm and could effectively improve the bacteria–electrode interaction. These features resulted in an enhanced coulombic efficiency up 13.2 %, nearly one order of magnitude higher than that of the CP (1.2 %). [ABSTRACT FROM AUTHOR]

Accumulation of high concentrations of Al(III) in body has a direct impact on health and therefore, the trace detection of Al(III) has been a matter for substantial concern. An anionic metal organic framework ({[Me2NH2]0.5[Co(DATRz)0.5(NH2BDC)] ⋅ xG}n; 1; HDATRz=3,5‐diamino‐1,2,4‐triazole, H2NH2‐BDC=2‐amino‐1,4‐benzenedicarboxylic acid, G=guest molecule) composed of two types of secondary building units (SBU) and channels of varying sizes was synthesized by employing a rational design mixed ligand synthesis approach. Free −NH2 groups on both the ligands are immobilized onto the pore surface of the MOF which acts as a superior luminescent sensor for turn‐on Al(III) detection. Furthermore, the large channels could allow the counter‐ions to pass through and get exchanged to selectively detect Al(III) in presence of other seventeen metal ions with magnificent luminescence enhancement. The observed limit of detection is as low as 17.5 ppb, which is the lowest among the MOF‐based sensors achieved so far. To make this detection approach simple, portable and economic, we demonstrate MOF filter paper test for real time naked eye observation. [ABSTRACT FROM AUTHOR]

Frontispiece: Distance versus Capillary Flow Dynamics-Based Detection Methods on a Microfluidic Paper-Based Analytical Device ( PAD) Keywords: analytical methods; capillary flow dynamics; machine learning; microfluidics; point-of-care diagnostics Analytical methods, capillary flow dynamics, machine learning, microfluidics, point-of-care diagnostics. [Extracted from the article]

The introduction of fluorinated moieties into drugs as well as the increase of their overall three‐dimensionality have become key strategies amongst medicinal chemists to generate sets of compounds with favorable drug‐like properties. However, the introduction of fluorinated cyclopropane ring systems which combines both strategies is not widely exploited to date. This paper reports synthetic strategies exploiting the reactivity of gem‐difluorocyclopropenes in dipolar cycloaddition reactions with azomethine ylides to afford sets of new fluorine‐containing 3‐azabicyclo[3.1.0]hexanes. In addition, the unexpected formation of complex trifluorinated scaffolds arising from proline esters and gem‐difluorocyclopropenes is highlighted along with computational studies to elucidate the underlying mechanism. This study presents new avenues towards pharmaceutically relevant fluorinated 3‐azabicyclo[3.1.0]hexanes that are accessible via robust and short synthetic sequences. [ABSTRACT FROM AUTHOR]

Accurate cancer diagnosis especially early diagnosis is of great importance for prompt therapy and elevated survival rate. mRNAs are widely used as biomarkers for cancer identification and treatment. mRNA expression levels are highly associated with cancer stage and malignant progression. Nevertheless, single type mRNA detection is insufficient and unreliable. Herein, we developed a DNA nano‐windmill probe for in situ multiplexed mRNAs detection and imaging in this paper. The probe is designed to simultaneously target four types of mRNA through wind blades. Importantly, recognition of targets is independent from each other, which further facilitate cell type discrimination. The probe can specifically distinguish cancer cell lines from normal cells. In addition, it can identify changes in mRNA expression levels in living cells. The current strategy enriches the toolbox for improving the accuracy of cancer diagnosis and therapeutic solutions. [ABSTRACT FROM AUTHOR]

N‐Heterocyclic carbenes (NHCs) have drawn considerable interest in the field of nanomaterials chemistry as highly stabilizing ligands enabling the formation of strong and covalent carbon–metal bonds. Applied to gold nanoparticles synthesis, the most common strategy consists of the reduction of a preformed NHC‐AuI complex with a large excess of a reducing agent that makes the particle size difficult to control. In this paper, we report the straightforward synthesis of NHC‐coated gold nanoparticles (NHC‐AuNPs) by treating a commercially available gold(I) precursor with an easy‐to‐synthesize NHC‐BH3 reagent. The latter acts as both the reducing agent and the source of surface ligands operating under mild conditions. Mechanistic studies including NMR spectroscopy and mass spectrometry demonstrate that the reduction of gold(I) generates NHC‐BH2Cl as a by‐product. This strategy gives efficient control over the nucleation and growth of gold particles by varying the NHC‐borane/gold(I) ratio, allowing unparalleled particle size variation over the range of 4.9±0.9 to 10.0±2.7 nm. Our strategy also allows an unprecedented precise and controlled seeded growth of gold nanoparticles. In addition, the as‐prepared NHC‐AuNPs exhibit narrow size distributions without the need for extensive purification or size‐selectivity techniques, and are stable over months. [ABSTRACT FROM AUTHOR]

The application of multiple quantum dots (QDs) in the field of white light emitting diodes (WLEDs) is still an important challenge due to their low luminous efficiency and quenching phenomenon. In this paper, we prepared AgInS2 QDs/zeolitic imidazolate framework‐70 (AIS/ZIF‐70) composite by a microwave hydrothermal method. Owing to the high porosity and stability of ZIF‐70, it could effectively prevent quenching issues due to the aggregation of QDs. Since the ZIF‐70 and QDs were chemically bonded, the formation of the ZnS layer could effectively passivate the surface defect and thus the quantum yield reached 21.49 % in aqueous solution. The luminous efficiency (LE) of the assembled AIS/ZIF‐based WLED was reinforced by 6.8 times with a molar ratio of AgIn/Zn=18, i. e. at 5.26 % molar fraction of ZIF‐70. Moreover, the color rendering index (CRI) and correlated color temperature (CCT) of AIS/ZIF‐based WLED were 84.3 and 3631 K, respectively, indicating its potential application in solid‐state lighting. [ABSTRACT FROM AUTHOR]

Multifunctional materials with working temperatures near room temperature are crucial for practical applications. Until now, it is still a great challenge to obtain such materials. In this paper, a complex of (C5NH13Cl)2MnBr4 (1) with a structural phase transition near room temperature is reported. The phase transition induces switchable magnetic properties, dielectric anomalies and luminescent response over the same range of temperatures. It is the first time the synergetic effect of magnetism, dielectricity and luminescence near room temperature have been observed in the same molecular complex. [ABSTRACT FROM AUTHOR]

This paper reports a photochemical C−N coupling of abundant, but less reactive aryl chlorides, with structurally diverse primary and secondary amides by Ni‐mediated without an external photocatalyst. Under the irradiation of light (390–395 nm) with a soluble organic amine as the base, the reaction allows for the successful transformation of (hetero)aryl chlorides to a wide range of N‐aryl amides. More than 60 examples are shown, demonstrating the feasibility and applicability of this protocol in organic synthesis. Mechanic studies indicate that this amidation proceeds via a Ni(I)‐Ni(III) catalytic cycle. [ABSTRACT FROM AUTHOR]

Hydrochromic materials, which change color in response to moisture, are highly sought‐after due to some unique applications such as moisture detection, humidity monitoring, anti‐counterfeiting, and sweat‐pore mapping. We herein report a new thioxanthene‐9‐ols/thioxanthylium cations hydrochromic system. The hydrochromic thioxanthylium cations can be generated/regenerated by exposing a chemically stable thioxanthene‐9‐ol to trifluoroacetic acid (TFA). The intensely colored thioxanthylium cations can be chemically reverted to the colorless thioxanthene‐9‐ol. Interestingly, the conversion between thioxanthene‐9‐ol and its cation species was found to be highly reversible in most cases (up to 50 activation‐deactivation cycles). The color and moisture‐sensitivity of thioxanthylium cations were also validated to be tunable via functionalization of the thioxanthene core with different aliphatic and aromatic groups at its 9 or 2,7‐positions. Finally, paper probes were prepared using solution‐immersion and inkjet‐printing techniques to demonstrate the system's potential applications in humidity sensing and anti‐counterfeiting [ABSTRACT FROM AUTHOR]

The crystallization of a complex having electron transfer properties in a polar space group can induce the polarization switching of a crystal in a specific direction, which is attractive for the development of sensors, memory devices, and capacitors. Unfortunately, the probability of crystallization in a polar space group is usually low. Noticing that enantiopure compounds crystallize in Sohncke space groups, this paper reports a strategy for the molecular design of non‐ferroelectric polarization switching crystals based on the use of intramolecular electron transfer and chirality. In addition, this paper describes the synthesis of a mononuclear valence tautomeric (VT) cobalt complex bearing an enantiopure ligand. The introduction of enantiomer enables the crystallization of the complex in the polar space group (P21). The polarization of the crystals along the b‐axis direction is not canceled out and the VT transition is accompanied by a change in the macroscopic polarization of the polar crystal. Polarization switching via electron transfer is realized at around room temperature. [ABSTRACT FROM AUTHOR]

The development of low‐cost and high‐efficiency bifunctional catalysts is still a challenge for hydrogen production through overall water splitting. This paper reports the in‐situ synthesis of C‐doped MoS2/CoP/MoO2 using bacterial cellulose (BC) as the reducing agent and the source of C and using BC (MoS2/Co1.2MoO4.2 ⋅ 1.2H2O/BC) as the template. Heterogeneous structure for hydrogen evolution reaction (HER) and alkaline water electrolysis in a wide pH range. Due to the large number of defect sites caused by C doping and the synergy between these three active components (MoS2, CoP and MoO2), the HER and oxygen evolution reaction (OER) activities of the catalyst have been greatly improved. Therefore, during HER, a small initial overpotential (27 mV) was achieved in 1.0 M KOH. In 0.5 M H2SO4, 0.1 M PBS and 1.0 M KOH, the current density reached 10 mA cm−2 at overpotentials of 123.4, 150, and 139 mV, respectively. For OER, an overpotential of 268 mV was required to achieve 10 mA cm−2. The alkaline two‐electrode device composed of C doped MoS2/CoP/MoO2 delivers 10 mA cm−2 at a low potential of 1.51 V and can be easily driven by a single AA battery. This work provides a new design strategy of C doped ternary heterostructures for electrocatalysis and related energy applications. [ABSTRACT FROM AUTHOR]

We report the first case of mechanochemical deracemization by using liquid‐assisted abrasive grinding. The target molecule is a precursor of Paclobutrazol, an important fungicide and plant growth inhibitor. Using mechanochemical deracemization, we are even able to transform a 10 % ee scalemic mixture of this latter in an enantioenriched product of 97 % ee in a couple of hours. This is substantially shorter compared to solution‐based deracemization methodologies. The present paper thus introduces an efficient and greener process to enantiopure material. [ABSTRACT FROM AUTHOR]

In this paper the density functional theory (DFT) method was employed to investigate the cross‐coupling of methanol with benzyl alcohol to afford methyl benzoate, catalysed by Mn‐PNN pincer complex. The whole reaction process mainly includes three stages: the dehydrogenation of benzyl alcohol to benzaldehyde, the coupling of benzaldehyde with methanol to hemiacetal and the dehydrogenation of hemiacetal to methyl benzoate. The calculated results indicated that two dehydrogenation processes are influenced by two competitive mechanisms of inner and outer spheres. Dehydrogenation of benzyl alcohol to benzaldehyde is the rate‐determining step of the whole reaction, with the energy barrier of 22.1 kcal/mol. In addition, the regeneration of catalyst is also extremely important. Compared with direct dehydrogenation, the dehydrogenation mode assisted by formic acid is more advantageous. This work might provide theoretical insights and shed light on the design of cheap transition‐metal catalysts for the dehydrogenation reaction. [ABSTRACT FROM AUTHOR]

Adrenaline, also known as epinephrine, is a neurotransmitter/hormone that is an important target in diagnostics. Development of an effective method for detecting it in the presence of other neurotransmitters is a challenging task. The electrochemical and fluorescent techniques commonly used have low selectivity in distinguishing among catecholamines. Herein, a small‐molecule organic probe with an activated furfural moiety is reported to exploit the nucleophilicity of epinephrine to generate a bright‐colored donor–acceptor Stenhouse adduct. Among nine common neurotransmitters or their analogues, only epinephrine was found to generate a unique colour change discernible with the naked eye, whereas the other ones remain unaffected. Under various in‐field detection conditions, including solution, droplet, and paper strip‐based detection, the colour change were also noticeable. The low detection limit of 1.37 nM and a limit of quantitation of 4.37 nM were achieved with simple UV/Vis methods in addition to the sub‐ppm level sensing under visual conditions with naked eyes. The probe could be used for practical colorimetric measurements as a point‐of‐care tool without any complex and expensive machinery, making this approach accessible to all. In addition, using a simple smartphone, the determination of epinephrine concentrations is possible by using machine‐learning techniques. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur batteries (LSBs) have been considered as one of the most promising energy storage systems owing to their high theoretical energy density and abundant sulfuric resources. However, their commercial application is limited by rapid capacity decline and low Coulombic efficiency. Metal–organic frameworks (MOFs) made of metallic nodes and organic ligands can suppress polysulfide shuttling and promote redox kinetics. In this paper, the effects of crystallographic dimensions and metallic categories on chemical performance of LSBs have been meticulously explored electrochemical performance. As a result, exposed Ni active sites in a lamellar Ni‐MOF was found to deliver a superior electrochemical performance. The as‐assembled LSBs with 2D‐Ni‐MOF/CNTs cathode deliver a much superior initial discharge capacity, (820 mAh g−1 at 0.5 C), and exhibit excellent cycling stability over 550 cycles than those analogues of 3D stereoscopic Ni‐MOF and 2D lamellar Co‐MOF. This work proposed a perspective in elevating LSBs performance through synergistic optimization of the MOFs dimensions and the metallic nuclei in the cathodes. [ABSTRACT FROM AUTHOR]

In this paper, a waxberry‐like MnS/Ni3S4 composite catalyst was designed and synthesized. In this coating structure, MnS is located inside and Ni3S4 is wrapped on the surface to form a spherical structure. This structure makes the material show excellent stability in the electrocatalytic process. The diffusion staggered region structure formed at the two‐phase interface greatly enhances the synergistic interaction between MnS and Ni3S4. At the same time, the defects and vacancies formed by the diffusion mechanism at the interface of the two phases increase the active site and improve the interfacial electron transfer kinetics. Therefore, MnS/Ni3S4 composites showed good catalytic performance for ORR/OER. At 10 mA cm−2, the overpotential of it is only 320 mV, and the half‐wave potential can reach 0.81 V. The catalyst also exhibited extraordinary cycle stability and small voltage gap when used as cathode of Zn‐air batteries. When the current density is 3 mA cm−2, the cyclic discharge can be stable for 400 h and the voltage difference between the front and back does not increase more than. When the current density increases to 5 mA cm−2, the cyclic charge and discharge can be stable for more than 300 h. [ABSTRACT FROM AUTHOR]

Transition metal radical‐type carbene transfer catalysis is a sustainable and atom‐efficient method to generate C−C bonds, especially to produce fine chemicals and pharmaceuticals. A significant amount of research has therefore been devoted to applying this methodology, which resulted in innovative routes toward otherwise synthetically challenging products and a detailed mechanistic understanding of the catalytic systems. Furthermore, combined experimental and theoretical efforts elucidated the reactivity of carbene radical complexes and their off‐cycle pathways. The latter can imply the formation of N‐enolate and bridging carbenes, and undesired hydrogen atom transfer by the carbene radical species from the reaction medium which can lead to catalyst deactivation. In this concept paper, we demonstrate that understanding off‐cycle and deactivation pathways not only affords solutions to circumvent them, but can also uncover novel reactivity for new applications. In particular, considering off‐cycle species involved in metalloradical catalysis can stimulate further development of radical‐type carbene transfer reactions. [ABSTRACT FROM AUTHOR]

For decades there were many attempts to dispense with stoichiometric amounts of metal reagents for the synthesis of secondary alcohols. In 2021, the synthetic results of Newman and collaborators pioneered a synthesis still with metals, but not as reactants. Instead, they serverd as catalytic engines. Here we present a description by means of Density Functional Theory calculations of how this process can occur, and an attempt is made to shed light on the mechanism that facilitates the attainment of secondary alcohols, emphasizing the eternal cross‐coupling debate of whether the catalytically active species is Ni(0) or they are really taking shortcuts following the course of Ni(II). Effective Orbital analyses give a clear picture. Furthermore, this paper provides insight not only into the nature of the ligands of the metal catalyst but also the role of the base. [ABSTRACT FROM AUTHOR]

This paper reports the synthesis of ruthenium‐based molecular gear prototypes composed of a brominated or non‐brominated pentaphenylcyclopentadienyl ligand as an anchoring unit and a tripodal ligand with aryl‐functionalized indazoles as a rotating cogwheel. Single crystal structures of the ruthenium complexes revealed that the appended aryl groups increase the apparent diameter of the cogwheel rendering them larger than the diameter of the anchoring units and consequently making them suitable for intermolecular gearing motions once the complexes will be adsorbed on a surface. [ABSTRACT FROM AUTHOR]

A highly flexible, fire ‐ resistant inorganic nanocomposite paper made from glass fibers (GFs) coated with network ‐ structured hydroxyapatite ultralong nanowires (NS ‐ HANWs) is shown on the cover picture. The NS ‐ HANWs/GFs paper has superior mechanical properties, low thermal conductivity and excellent heat insulation performance. This new material could be promising for many applications such as in the protection layer of fire ‐ retardant optical fiber cables, printing/copying/writing paper, nonflammable China paper, fire ‐ retardant wallpaper, and fireproof specialty paper. More information can be found in the Full Paper by Y. ‐ J. Zhu and L. ‐ Y. Dong on page 4597 ff. [ABSTRACT FROM AUTHOR]