We exploit liquid marbles as miniature platforms for controlling the self‐assembly of hydroxypropyl cellulose into a cholesteric liquid crystal that shows structural coloration by Bragg reflection. By adjusting the self‐assembly parameters, we can tailor for structural color anywhere in the visible. Liquid marbles respond with color changes that can be detected by eye, to changes in temperature, compression, and exposure to toxic chemicals. Abstract Liquid marbles have potential to serve...
Wed Aug 26, 2020 20:52
Hierarchically structured interfaces to living cells can be established by functionalizing nanoparticle‐modified DNA polymer materials with agonists or antagonists of transmembrane receptors. Abstract We report on the directed postsynthetic functionalization of soft DNA nanocomposite materials with proteins. Using the example of the functionalization of silica nanoparticle‐modified DNA polymer materials with agonists or antagonists of the epidermal growth factor receptor EGFR cell membrane...
Wed Aug 26, 2020 20:51
The expanded analogs of 3D halide perovskites reported herein can hold relatively large aromatic cations in the spacious inorganic sublattice. The band gap of these materials is set by the empty low‐lying orbitals of the organic molecules and the filled orbitals of the inorganic components. The molecular nature of the conduction band allows us to electronically dope the materials through simple redox chemistry. Abstract Replacing the Pb−X octahedral building unit of AIPbX3 perovskites (X=halide)...
Wed Aug 26, 2020 20:51
A facile and non‐destructive method is developed to remove the capping agent from the surface of Pd nanocubes by heating the sample in water containing a trace amount of N2H4. The as‐obtained nanocubes show clean and smooth {100} faces with optimal activity toward formic acid oxidation at low overpotentials. Abstract We report a robust method for effectively removing the chemisorbed Br− ions, a capping agent, from the surface of Pd nanocubes to maximize their catalytic activity. The Br−...
Wed Aug 26, 2020 20:51
A freestanding porphyrin‐based monoatomic layer can be easily synthesized from the nanometer scale to the millimeter scale via bottom‐up growth. Both its structure and property are analogous to graphene. The monoatomic layers show remarkable metal center dependence of the catalytic activity and selectivity for CO2 electroreduction. Abstract Developing two‐dimensional (2D) and single atomic layered materials is a fascinating challenge. Here we successfully synthesize porphyrin‐based monoatomic...
Wed Aug 26, 2020 20:51
Enhancing photoswitching efficiency: In the donor–acceptor substituted dihydropyrene dimer the quantum yield for the second ring‐opening is enhanced by more than two orders of magnitude compared to the first ring‐opening. Responsible is a cooperative switching effect which has been rationalized by theoretical calculations and is a general phenomenon for dihydropyrene dimers connected through suitable bridges in the 2,7‐positions. Abstract We present a strategy to achieve highly cooperative...
Wed Aug 26, 2020 20:51
Amides and esters bearing a quaternary β‐carbon atom are synthesized by a domino reaction involving C(sp3)−H activation, 1,4‐Pd shift, and amino/alkoxycarbonylation. Mechanistic studies showed that the aminocarbonylation of the σ‐alkylpalladium intermediate arising from the palladium shift is fast, and leads to the amide rather than the previously reported indanone product. Abstract The 1,4‐palladium shift strategy allows the functionalization of remote C−H bonds that are difficult to reach...
Wed Aug 26, 2020 20:50
In situ growth of ultrathin FeNi oxyhydroxides on BiVO4 photoanodes by a simple pH‐modulated immersion significantly promoted the oxygen evolution activities and stability. This is attributed to the selectively interfacial bonding of Fe and Ni with surface Bi and V sites. Abstract Understanding the origin of formation and active sites of oxygen evolution reaction (OER) cocatalysts is highly required for solar photoelectrochemical (PEC) devices that generate hydrogen efficiently from water....
Wed Aug 26, 2020 20:50
Record‐setting amounts of small hydrocarbon gas molecules such as acetylene and ethylene can be captured in a bimetallic cobalt–vanadium material synthesized by an unusual form of pore‐space partition. Abstract Introduction of pore partition agents into hexagonal channels of MIL‐88 type (acs topology) endows materials with high tunability in gas sorption. Here, we report a strategy to partition acs framework into pacs (partitioned acs) crystalline porous materials (CPM). This strategy is...
Wed Aug 26, 2020 20:50
Transient absorption microscope (TAM) images can be mapped one to one with the SEM image in grain boundaries and interiors of a perovskite thin film and find correlation between the morphology and carrier relaxation kinetics. Abstract We developed a direct mapping approach to overlay the image of a polycrystalline perovskite film obtained from the transient absorption microscope (TAM) with that from the scanning electron microscope (SEM). By mapping these imaging data pixel by pixel, we...
Wed Aug 26, 2020 20:50
A ferroelectricity‐driven self‐powered ultraviolet photodetector employing a 2D hybrid perovskite ferroelectric (BPA)2PbBr4 (BPA=3‐bromopropylammonium) is presented. It shows strong polarization sensitivity, with a large polarization ratio of up to 6.8. Abstract Polarization‐sensitive ultraviolet (UV) photodetection is highly indispensable in military and civilian applications and has been demonstrated with various wide‐band photodetectors. However, it still remains elusive to achieve the...
Wed Aug 26, 2020 20:50
Two distance‐dependent phenomena (surface plasmonic field and mediated electron transfer) were combined to enable washing‐free electrochemical DNA detection. The surface plasmonic field decaying exponentially from a gold electrode induced rapid photoredox catalysis of the surface‐bound catalytic label (eosin Y, EY2−), and mediated electron transfer allowed for rapid electron transfer from eosin Y to the Au electrode (see picture; TEOA=triethanolamine). Abstract Distance‐dependent electromagnetic...
Wed Aug 26, 2020 20:50
Polymerization‐induced self‐assembly enables the at scale synthesis of nanoparticles with a high‐density display of peptide, tunable particle size, and tunable peptide loadings. The resulting peptide brush polymer nanoparticles exhibit enhanced stability, and cell uptake efficiency and efficacy in comparison with their peptide analogues, highlighting the potential of these peptide–polymer amphiphiles as peptide delivery systems. Abstract Herein, we report the photoinitiated polymerization‐induced...
Wed Aug 26, 2020 20:49
Proteolytic profiling of disease‐tissue lysates using highly diverse substrate libraries enables a streamlined development of in‐vivo imaging probes and diagnostics without prior knowledge of target enzymes. This has the potential to be applied to diverse disease states using clinical or animal‐model tissue samples Abstract Fluorescently quenched probes that are specifically activated in the cancer microenvironment have great potential application for diagnosis, early detection, and surgical...
Wed Aug 26, 2020 20:49
The exploration of optimal geometrical site in Co3O4 for electrochemical HMF oxidation by the building tetrahedral (Zn2+) and octahedral (Al3+) blocks is described. The electrochemical results demonstrate that Co3+ Oh are the best geometrical sites for HMF oxidation, and the chemical adsorption for acidic organic molecules are dominated by Co2+ Td. The exposure degree of Co3+ is improved by Cu2+ and thus results in a record activity. Abstract Co‐based spinel oxides, which are of mixing...
Wed Aug 26, 2020 20:49
Tillandsia‐inspired hygroscopic photothermal organogel (POG) is developed to realize atmospheric water harvesting. The combination of designable hydrophilic co‐polymeric skeleton, hygroscopic liquid medium, and photothermic component endows POG continuous, high‐efficient moisture sorption and effective solar‐heating water releasing. Abstract Tillandsia species with degenerated roots have evolved into hygroscopic leaves that absorb moisture from air. This interesting biological adaptability...
Wed Aug 26, 2020 20:49
A general composite‐micelle‐directed interfacial assembly method was developed to prepare mesoporous heterostructures (see picture). With their structural and compositional advantages, the unique sandwichlike mesoporous carbon@MXene@mesoporous carbon heterostructured nanosheets exhibited remarkable electrochemical performance as a cathode material for lithium–sulfur batteries. Abstract Two‐dimensional (2D) mesoporous heterostructures combining ultrathin nanosheet morphology, periodic porous...
Wed Aug 26, 2020 20:48
An NMR experiment for studying fully protonated high molecular weight complexes (>100 kDa), the XL‐ALSOFAST‐HMQC with delayed decoupling is introduced. Its high sensitivity of up to 5‐fold higher than currently used state‐of‐the‐art experiments allows its application to challenging biological samples like unstable membrane protein preparations or natural abundance measurements to characterize therapeutic antibodies. Abstract Current biological research increasingly focusses on large...
Wed Aug 26, 2020 20:48
A facile impregnation‐calcination route has been developed for the general synthesis of various metal clusters, having sizes of about 1.0 nm, by double confinement. The resulting Cu clusters confer a high selectivity for the carbon dioxide reduction reaction with a maximum Faraday efficiency of 81.7 % for methane. Abstract Previous density‐functional theory (DFT) calculations show that sub‐nanometric Cu clusters (i.e., 13 atoms) favorably generate CH4 from the CO2 reduction reaction (CO2RR),...
Wed Aug 26, 2020 20:48
A mono‐coordinated silicon cation was prepared by halide abstraction from a iodosilylene. It is shown to react with an amine to form three bonds at the silicon atom in one reaction which conforms with the notion of a “supersilylene”. Abstract Mono‐coordinated silicon(II) cations are predicted to be reactive ambiphiles, combining the typically high Lewis acidity of silicon cations with nucleophilicity due to the presence of an electron pair at the same atomic centre. Here, a carbazole‐derived...
Wed Aug 26, 2020 20:47
A new type of MOS was successfully synthesized and employed for the construction of two new ZSA materials with MER and ABW underlying topologies. The introduction of this distinct MOS attests to the prospect of constructing new ZSA materials, and at the same time magnifies the plausible use of 4MR SBUs for the construction of ZMOFs. Abstract Our conceived approach based on the directed assembly of functional metal–organic squares (MOSs), 4‐membered ring (4MR) building units, permitted the...
Wed Aug 26, 2020 20:44
Luminogens for a superior time‐resolved (TR) imaging effect with channel selectivity were achieved by engineering dual thermally activated delayed fluorescence (TADF) from anti‐Kasha/Kasha emission pathways. Intracellular local imaging information that is serialized and integrated was observed by calibrating the two TR signals. The technology is pertinent to precision medicine as TR signals are typically difficult to access in weak emission areas. Abstract The fact that the lifetime of...
Wed Aug 26, 2020 20:44
Spatially responsive photonic barcodes have been designed based on spatially resolved responsive multicolor Ln‐MOF heterostructures, which facilitate an efficient authentication and exhibit great potential in fulfilling advanced anti‐counterfeiting. These results offer a comprehensive understanding of the function‐oriented construction of responsive hybrid MOF materials to achieve miniaturized security labels. MOF=metal—organic framework Abstract Micro/nanoscale photonic barcodes based...
Wed Aug 26, 2020 20:44
A trifunctional ether‐based redox mediator, DBDMB, is introduced into the electrolyte to capture reactive discharge intermediates (O2 −) with reduced formation of by‐products, regulate solution growth of Li2O2, and co‐oxidize Li2O2 and by‐products (Li2CO3 and LiOH). Li‐O2 batteries with large capacity and long cycling stability have been achieved. Abstract Li‐O2 batteries with ultrahigh theoretical energy densities usually suffer from low practical discharge capacities and inferior cycling...
Wed Aug 26, 2020 20:43
Trace acetylene can be efficiently separated from ethylene via the synergistic effect of high‐density open metal and electronegative sites in an ultramicroporous metal–organic framework (MOF). The specific binding sites in the MOF afford an excellent acetylene uptake at 0.01 bar by maximizing the host–guest interactions. Abstract Acetylene (C2H2) removal from ethylene (C2H4) is a crucial step in the production of polymer‐grade C2H4 but remains a daunting challenge because of the similar...
Wed Aug 26, 2020 20:42
The phase of stoichiometric D3S, synthesized from elemental S and excess D2 in a diamond anvil cell, exhibits superconductivity with T c of 166 K at 157 GPa. This is significantly higher than previously reported circa 150 K for samples prepared from disproportionated D2S. Abstract The discovery of superconductivity in H3S at 203 K marked an advance towards room‐temperature superconductivity and demonstrated the potential of H‐dominated compounds to possess a high critical temperature...
Wed Aug 26, 2020 20:42
We detected individual Pt nanoparticles colliding with electrocatalytically active and partially active electrodes. The observed current transients explain the electrochemical reactions occurring on the impacting nanoparticles. The measurements allow elucidation of plausible deactivation mechanisms for the hydrogen evolution and oxygen reduction reactions on platinum catalysts. Abstract While the electrochemical nanoimpact technique has recently emerged as a method of studying single entities,...
Wed Aug 26, 2020 20:42
Constructing three‐dimensional (3D) structural characteristics on two‐dimensional (2D) covalent organic frameworks (COFs) is a smart approach to effectively improve the pore permeability and mass transfer rate of the materials and realize the rapid adsorption for guest molecules, while avoiding the high cost and monomer scarcity in preparing 3D COFs. Herein, we report for the first time a series of colyliform crystalline 2D COFs with quasi‐three‐dimensional (Q‐3D) topologies, consisting of unique...
Wed Aug 26, 2020 18:01
A tandem Bischler‐Napieralski/semipinacol rearrangement reaction has been developed for the purpose of assembling spiro dicyclic indole framework, a privileged structural unit of aspidofractinine type monoterpenoid indole alkaloids. In combination with a sequential Mannich reaction, the contracted central bridge ring system (bicyclic[2.2.1]heptane) of these molecules with contiguous quaternary centers could be expeditiously constructed. Development of this novel strategy finally culminated in the...
Wed Aug 26, 2020 18:00
Proteins are in continuous motion, with their structural dynamic behavior crucial to function. However, the majority of protein structures have been elucidated under equilibrium conditions. We aim to provide a better understanding of the dynamic behavior inherent to proteins by fabricating a label‐free nanodevice comprising a single‐peptide junction for the first time, to measure real‐time conductance from which their structural dynamic behavior can be inferred. This device contains an azobenzene...
Wed Aug 26, 2020 17:58
To develop high‐performance nonlinear optical (NLO) materials for infrared (IR) applications, we have applied a rational element‐composition design strategy and investigated the unexplored PbO–PbCl 2 –PbI 2 system. By doing so, a new polar lead mixed oxyhalide, Pb 18 O 8 Cl 15 I 5 , representing the first synthetic metal oxyhalide combining both Cl – and I – was discovered. Pb 18 O 8 Cl 15 I 5 reveals an unprecedented structural feature with two different dimensional types of oxocentered...
Wed Aug 26, 2020 17:00
The transition‐metal‐catalyzed cyanations of aryl halides are among the most used methods for synthesizing aryl nitriles. Despite tremendous advances, cyanating an aryl halide in a facile and benign fashion has generally been unsuccessful. The challenge for this significant transformation is the strong affinity of cyanide for metal centers, which makes organometallic catalysis elusive by hampering oxidative addition and reductive elimination. Herein, we demonstrate for the first time that nickel‐catalyzed...
Wed Aug 26, 2020 17:00
Insights gained from a comparison of aminometalation reactions with lithium amides, potassium amides and mixed lithium/potassium amides are presented. A combination of structural characterization, DFT calculations and electrophile reactions of aminometalated intermediates has shown the advantages of using a mixed metal strategy. While potassium amides fail to add, the lithium amides are uncontrollable and eliminated, yet the mixed K/Li amides deliver the best of both. Aminopotassiation proceeds to...
Wed Aug 26, 2020 22:00
The catalytic oxidative coupling of methane (OCM) to C2 hydrocarbons with oxygen (O 2 ‐OCM) has garnered renewed worldwide interest in the past decade due to the emergence of enormous new shale gas resources. However, the C2 selectivity of typical OCM processes is significantly challenged by overoxidation to CO x products. Other gaseous reagents such as N 2 O, CO 2 , and S 2 have been investigated to a far lesser extent as alternative, milder oxidants to replace O 2 . Although several...
Wed Aug 26, 2020 19:43
Most metallo‐supramolecular assemblies of low nuclearity adopt simple topologies, with bridging ligands spanning neighboring metal centers in a direct fashion. Here we contribute a new structural motif to the family of host compounds with low metal count (two) that consists of a pair of doubly‐interlocked, figure‐eight‐shaped subunits, also termed “lemniscates”. Each metal is chelated by two chiral bidentate ligands, composed of a peptidic macrocycle that resembles a natural product with two pyridyl‐terminated...
Wed Aug 26, 2020 17:51
Catalysis by metal bridging: Sulfonate NHC–Cu catalysts promote a variety of transformations with uniquely high efficiency as well as regio‐, and enantioselectivity. The origins of the discovery of these chiral complexes, the process that they are adept at catalyzing, comparison with alternative approaches, and different applications to total synthesis are presented. Abstract A copper‐based complex that contains a sulfonate N‐heterocyclic carbene ligand was first reported 15 years ago....
Wed Aug 26, 2020 15:42
MOFs have highly ordered self‐assembled nanostructure, high‐surface area, nano porosity with tunable size and shape, reliable host–guest interaction and responsiveness to physical and chemical stimulus which can be exploited to address the critical issues in sensor application. On one hand, the nanoscale pore size of MOFs ranging from <1 nm to ~10 nm not only allows the diffusion of minor sized molecules into the pore or through the MOF layer, but also excludes other molecules with larger size...
Wed Aug 26, 2020 14:50
Chirality transfer is widely observed in life processes, and many artificial chiral transfer systems have been developed. In these systems, chiral information is transferred from chiral inducers to chiral acceptors by a direct chiral induction process and a direct chiral memorization process. Herein we developed ternary nondirect chiral transfer systems based on pillar[5]arenes, in which a third factor was introduced as a regulator. The planar chirality of an acceptor was induced and memorized by...
Wed Aug 26, 2020 14:49
Glaser‐like coupling of terminal alkynes by thermal activation is extensively used in on‐surface chemistry. Here we demonstrate an intramolecular version of this reaction performed by atom manipulation. We used voltage pulses from the tip to trigger a Glaser‐like coupling between terminal alkyne carbons within a custom synthesized precursor molecule adsorbed on bilayer NaCl on Cu(111). Different conformations of the precursor molecule and the product were characterized by molecular structure elucidation...
Wed Aug 26, 2020 14:20
Hollow organic molecular cocrystals comprised of 9‐methylanthracene‐1,2,4,5‐tetracyanobenzene (9MA‐TCNB) and naphthalene‐1,2,4,5‐tetracyanobenzene (NAPH‐TCNB) were fabricated using a surfactant mediated co‐reprecipitation method. The crystals exhibit a narrow size distribution that can be easily tuned by varying the concentration of surfactant and incubation temperature. The rectangular crystals possess symmetrical twinned cavities with an estimated storage volume on the order of 10‐10 L. An aqueous...
Wed Aug 26, 2020 11:25
RNA‐RNA interactions are essential for biology, yet they can be difficult to study due to their transient nature. While crosslinking strategies can in principle be used to trap such interactions, virtually all existing strategies for crosslinking are poorly reversible, chemically modifying the RNA and hindering molecular analysis. Here, we describe a soluble crosslinker design (BINARI) that reacts with RNA via acylation. We find that it efficiently crosslinks noncovalent RNA complexes with miminal...
Wed Aug 26, 2020 12:51
Achieving well‐defined polymers with ultrahigh molecular weight (UHMW) is an enduring pursuit in the field of reversible deactivation radical polymerization. Synthetic protocols have been successfully developed to achieve UHMWs with low dispersities exclusively from conjugated monomers while no polymerization of unconjugated monomers has provided the same level of control. Herein, an oxygen‐tolerant photoenzymatic RAFT polymerization is exploited to tackle this challenge for unconjugated monomers...
Wed Aug 26, 2020 11:49
The science of particles on a sub‐nanometer (~ 1 nm) scale has attracted worldwide attention. However, this field of science has remained unexplored because of the technical difficulty in the precise synthesis of sub‐nanoparticles (SNPs). Thus, we recently developed the ‘atom‐hybridization method (AHM)’ that precisely synthesizes the SNPs by using a suitably‐designed macromolecule as a template. In this study, toward revealing this unexplored field, we newly investigated the chemical reactivity of...
Wed Aug 26, 2020 11:18
Allosteric inhibition of the SARS‐CoV‐2 main protease – insights from mass spectrometry‐based assays
Following translation of the SARS‐CoV‐2 RNA genome into two viral polypeptides, the main protease M pro cleaves at eleven sites to release non‐structural proteins required for viral replication. M Pro is an attractive target for antiviral therapies to combat the coronavirus‐2019 disease (COVID‐19). Here, we have used native mass spectrometry (MS) to characterize the functional unit of M pro . Analysis of the monomer‐dimer equilibria reveals a dissociation constant of K d = 0.14 ± 0.03 µM,...
Tue Aug 25, 2020 22:00
Rhizolutin ( 1 ) was discovered as a natural product of ginseng‐rhizospheric Streptomyces sp. WON17. Its structure featured an unprecedented 7/10/6‐tricyclic dilactone carbon skeleton composed of dimethylcyclodecatriene flanked by a 7‐membered and a 6‐membered lactone ring based on spectroscopic analysis. During an unbiased screening of natural product libraries, this novel compound was found to dissociate amyloid‐β (Aβ) plaques and tau tangles, which are key pathological hallmarks of Alzheimer’s...
Tue Aug 25, 2020 20:49
ZIF‐8 membrane has emerged as the most promising candidate for propylene/propane (C3H6/C3H8) separation due to its precise molecular sieving characteristics. The poor reproducibility and durability, high cost, thus far pose challenges on the scalable synthesis and industrial application of ZIF‐8 membranes. Herein, we report a semi‐solid process featured with ultrafast and high‐yield synthesis, and outstanding scalability for reproducible fabrication of ZIF‐8 membranes. The resultant membranes exhibit...
Tue Aug 25, 2020 20:47
The first series of bis(silylene)‐stabilized nitrogen(I) compounds is described. Starting from the 1,2‐bis(N‐heterocyclic silylenyl) 1,2‐dicarba‐closo‐dedocaborane(12) scaffold 1, [1,2‐(LSi)2C2B10H10; L = PhC(NtBu)2], its reaction with the adamantyl azide (AdN3) affords the terminal N‐μ2‐bridged zwitterionic carborane‐1,2‐bis(silylium) AdN3 adduct 2 with an open‐cage dianionic nido‐C2B10 cluster core. Remarkably, upon one‐electron reduction of 2 with C8K and liberation of N2 and adamantane, the two...
Tue Aug 25, 2020 20:37
A robust platform is developed to assemble sub‐10 nm organic aggregation‐induced emission (AIE) particles using four different AIE luminogens (AIEgens) with emissions from green to the second near‐infrared window (NIR‐II). They are called AIE quantum dots (QDs) to distinguish from tipycal AIE dots which are larger than 25 nm. Compared with AIE dots that are larger than 25 nm, AIE QDs allow more efficient cellular uptake and imaging without surface modification of any membrane‐penetrating peptides...
Tue Aug 25, 2020 20:36
Soft porous crystals (SPCs) can undergo cooperative stimuli‐responsive structural transitions that strongly impact the physical properties and pore structure of the crystal. Hysteretic behavior and counterintuitive adsorption phenomena are a consequence of the complex energy landscapes and cooperativity of SPCs with regard to adsorption/desorption‐induced deformation. Abstract In this Minireview, we discuss the fundamental chemistry of soft porous crystals (SPCs) by characterizing their...
Tue Aug 25, 2020 20:21
Upconverting nanoparticles (UCNPs) are promising candidates for photon‐driven reactions, including light‐triggered drug delivery, photodynamic therapy, and photocatalysis. Here, we investigate the NIR to UV and visible emission of sub‐15 nm alkaline‐earth rare‐earth fluoride UCNPs (M 1‐x Ln x F 2+x, MLnF) with a CaF 2 shell. We synthesize 8 alkaline‐earth host materials doped with Yb 3+ and Tm 3+ , with alkaline‐earth (M) spanning Ca, Sr, and Ba, MgSr, CaSr, CaBa, SrBa, and CaSrBa. We...
Tue Aug 25, 2020 20:03
The electrolytes in lithium metal batteries have to be compatible with both lithium metal anodes and high voltage cathodes, which can be regulated by manipulating the solvation structure. Herein, to enhance the electrolyte stability, lithium nitrate (LiNO3) and HFE are introduced into the high‐concentration sulfolane electrolyte to suppress Li dendrite growth and achieves a high Coulombic efficiency of >99% for both Li anode and LiNi0.8Mn0.1Co0.1O2 (NMC811) cathodes. Molecular dynamics simulations...
Tue Aug 25, 2020 19:34
A design‐led dual‐templating approach was used to create a hierarchical zeotype catalyst with superior mass transport properties. Advanced probe‐based characterization (including positron annihilation lifetime spectroscopy and probe‐based IR spectroscopy) shows how the siliceous mesoporogen modulates the porosity and moderates the acidity of the zeotype framework, leading to enhanced catalytic performance. Abstract Porosity and acidity are influential properties in the rational design of...
Tue Aug 25, 2020 19:22
Recent advances in the search for practical next‐generation deep‐UV NLO crystals are reviewed. The aim is to provide a clear perspective on the development of current deep‐UV NLO candidates, and to accelerate the discovery of future candidates with high performance to meet the urgent demand. NLO=nonlinear optical. Abstract Advances in the generation of coherent lasers at wavelengths below 200 nm as well as the associated equipment and technologies have greatly spurred the development of...
Tue Aug 25, 2020 19:22
Ortho vs. meta: C−H alkylations of arylpyrazoles is achieved through ruthenium‐catalyzed C−H or C−C activation. The site‐selectivity is controlled by the pyrazole substituents and the steric hindrance of the alkyl moiety. Abstract Ruthenium(II)biscarboxylate complexes enabled the selective alkylation of C−H and C−C bonds at the ortho‐ or meta‐position. ortho‐C−H Alkylations were achieved with 4‐, 5‐ as well as 6‐membered halocycloalkanes. Furthermore, the judicious choice of the directing...
Tue Aug 25, 2020 19:21
Asymmetric transfer hydrogenation of gem‐difluorocyclopropenyl esters using the Noyori–Ikariya catalyst and isopropanol as the hydrogen donor provides access to enantioenriched gem‐difluorocyclopropanes (ee=66–99 %), which are emerging fluorinated motifs of interest in medicinal chemistry. Abstract Catalytic enantioselective access to disubstituted functionalized gem‐difluorocyclopropanes, which are emerging fluorinated motifs of interest in medicinal chemistry, was achieved through asymmetric...
Tue Aug 25, 2020 19:21
Despite black phosphorus quantum dots (BP QDs) have been revealed their significant prospects in biomedical field, virtually no reports involved BP QDs’s optical imaging in second near infrared (NIR‐II) region due to the unsatisfactory NIR‐II light absorption property of BP QDs. Herein, a silver ion (Ag + )‐coupled BP vesicle (BP Ve‐Ag + ) with a pioneering NIR‐II photoacoustic (PA) imaging capability was firstly constructed to maximize BP QD’s potential in deeper bioimaging and diversified therapy....
Tue Aug 25, 2020 19:21
Deep learning enables the holistic pK a prediction of various types of X−H acidities in 39 types of solvents. The accuracy of the predictions is demonstrated by a mean absolute error of 0.87 pK a units. Abstract While many approaches to predict aqueous pK a values exist, the fast and accurate prediction of non‐aqueous pK a values is still challenging. Based on the iBonD experimental pK a database (39 solvents), a holistic pK a prediction model was established using machine learning....
Tue Aug 25, 2020 19:20
The intercalation mechanism of high‐charge Al3+ ions in cationic‐defective anatase was elucidated and provides fundamental insights into key factors that impact the total number of inserted ions. Such factors are the nature of insertion sites, their surrounding anions, and the polarising power of Al3+. Abstract Aluminium batteries constitute a safe and sustainable high‐energy‐density electrochemical energy‐storage solution. Viable Al‐ion batteries require suitable electrode materials that...
Tue Aug 25, 2020 19:20
Delocalized, not classical: Despite its structural relationship to the non‐classical 7‐norbornenyl system earlier studies predicted the cyclopenten‐4‐yl cation to be a localized, classical carbocation. We have now been able to capture two stable derivatives of this elusive species by making use of anchoring aluminyl substituents and established a highly delocalized π aromatic structure. Abstract Theoretical studies predicted the planar cyclopenten‐4‐yl cation to be a classical carbocation,...
Tue Aug 25, 2020 19:20
A dipeptide‐based supramolecular catalyst with an ordered hierarchical nanostructure was developed through directional self‐assembly. The assembled chain‐like nanoarchitecture possessed switchable, enhanced enzyme‐like catalytic activity as compared to the natural counterpart (see picture). This approach offers potential for the construction of robust supramolecular biocatalysts for chemical transformations. Abstract Achieving synthetic architectures with simple structures and robust biomimetic...
Tue Aug 25, 2020 19:19
Chiral transient directing group (cTDG) strategies give rise to fundamentally new concepts in asymmetric C−H activation and enable the synthesis of chiral molecules without the need of pre‐installation and removal of directing groups. This Minireview provides an overview of recent advances in cTDG for the construction of chiral compounds with different types of chirality. Abstract Transition metal‐catalyzed enantioselective functionalization of C−H bond, the most abundant functionality...
Tue Aug 25, 2020 19:19
A series of isostructural Py‐XTP‐BT‐COFs (X=H, F, Cl) are systematically investigated as the catalysts for photocatalytic H2 production under visible light irradiation. The halogen modulation of Py‐HTP‐BT‐COFs realizes effective regulation of proper electronic structures, boosting the photo‐charge separation and reduction of the energy barrier for achieving highly efficient H2 production. Abstract Two‐dimensional covalent organic frameworks (2D COFs), an emerging class of crystalline porous...
Tue Aug 25, 2020 19:19
Oligonucleic acid conjugated aggregation‐induced emission photosensitizing nanoparticles were developed to realize light‐induced self‐escape of spherical nucleic acid from endo/lysosomes for efficient non‐cationic gene delivery and cancer treatment. Abstract Developing non‐cationic gene carriers and achieving efficient endo/lysosome escape of functional nucleic acids in cytosol are two major challenges faced by the field of gene delivery. Herein, we demonstrate the concept of self‐escape...
Tue Aug 25, 2020 19:19
9,10‐diboraanthracenes (DBAs) stabilized by cyclic (alkyl)amino)carbenes (cAACs) are prepared. EPR spectroscopy and quantum chemistry established disjointed singlet biradical ground states for these molecules, which provides experimental evidence for the predicted open‐shell configurations of larger acenes. The incorporation of two boron atoms is a suitable way to lower the HOMO–LUMO band gaps of acene‐type species. Abstract Narrow HOMO–LUMO gaps and high charge‐carrier mobilities make...
Tue Aug 25, 2020 19:19
A photochemical potential generated by the excitation of localized surface plasmon resonances of a bimetallic Au@Pt nanoparticle catalyst boosts electrochemical ammonia oxidation activity. Abstract We study how visible light influences the activity of an electrocatalyst composed of Au and Pt nanoparticles. The bimetallic composition imparts a dual functionality: the Pt component catalyzes the electrochemical oxidation of ammonia to liberate hydrogen and the Au component absorbs visible...
Tue Aug 25, 2020 19:18
Nanotechnology based on functional nucleic acids (FNAs) is an interdisciplinary field that builds on the interactions between FNAs and nanomaterials. In this Review, a number of common FNA nanomaterials are described along with their structures and applications. The most successful synthetic methods for the construction of highly developed FNA‐nanomaterial systems are described. Abstract Functional nucleic acid (FNA) nanotechnology is an interdisciplinary field between nucleic acid biochemistry...
Tue Aug 25, 2020 19:18
A nickel/Josiphos‐based catalytic system is shown to be very efficient for the mono‐α‐arylation of acetone with (hetero)aryl chlorides and phenol derivatives. Broad functional‐group tolerance was observed, and the desired products were obtained in good to excellent yields. Mechanistic studies allowed the isolation of catalytic intermediates and provided a rationale for the key role of the ligand. Abstract The challenging nickel‐catalyzed mono‐α‐arylation of acetone with aryl chlorides,...
Tue Aug 25, 2020 19:18
Tighter spatial constraints around titanium active sites in microporous and mesoporous materials promote the stereoselective isomerization of d‐glucose toward l‐sorbose over d‐fructose. Abstract Aqueous‐phase isomerization of d‐glucose to d‐fructose and l‐sorbose is catalyzed in parallel by Lewis acidic Ti sites in siliceous frameworks. Glucose isomerization rates (per Ti, 373 K) are undetectable when Ti sites are confined within mesoporous voids (Ti‐MCM‐41, TiO2‐SiO2) and increase to detectable...
Tue Aug 25, 2020 19:17
Aqueous redox flow batteries (RFBs) are promising alternatives for large‐scale energy storage. However, new organic redox‐active molecules with good chemical stability and high solubility are still desired for high‐performance aqueous RFBs due to their low crossover capability and high abundance. Herein, we report azobenzene‐based molecules with hydrophilic groups as new active materials for aqueous RFBs by utilizing the reversible redox activity of azo groups. By rationally tailoring the molecular...
Tue Aug 25, 2020 19:17
CRISPR, a sensing and actuating machine, mediates biosensing toward point‐of‐care diagnosis and understanding cellular biology. Abstract Recent advances in CRISPR based biotechnologies have greatly expanded our capabilities to repurpose CRISPR for the development of biomolecular sensors for diagnosing diseases and understanding cellular pathways. The key attribute that allows CRISPR to be widely utilized is the programmable and highly selective mechanism. In this Minireview, we first illustrate...
Tue Aug 25, 2020 19:14
Reversible clipping: The dynamic covalent opening and closing of disulfide macrocycles allowed the diameter‐selective functionalization of SWCNTs with mechanically interlocked rings. Abstract The formation of discrete macrocycles wrapped around single‐walled carbon nanotubes (SWCNTs) has recently emerged as an appealing strategy to functionalize these carbon nanomaterials and modify their properties. Here, we demonstrate that the reversible disulfide exchange reaction, which proceeds under...
Tue Aug 25, 2020 19:13
Organized media like bilayers have a substantial influence on the course of RAFT polymerization. Differential reactivity arose based on the placement and mobility of monomers, crosslinkers, and chain‐transfer agents within the bilayer. Abstract Co‐localization of monomers, crosslinkers, and chain‐transfer agents (CTA) within self‐assembled bilayers in an aqueous suspension enabled the successful directed assembly of nanocapsules using a reversible addition–fragmentation chain transfer (RAFT)...
Tue Aug 25, 2020 19:13
A rhodium(I)‐catalyzed enantioselective silylation of aliphatic C–H bonds for the synthesis of silicon‐stereogenic dihydrobenzosiloles is demonstrated. This reaction involves a highly enantioselective intramolecular C(sp3)−H silylation of dihydrosilanes, followed by a stereospecific intermolecular alkene hydrosilylation leading to the asymmetrically tetrasubstituted silanes. A wide range of dihydrosilanes and alkenes displaying various functional groups are compatible with this process, giving access...
Tue Aug 25, 2020 19:11
The electrochemical performance of vanadium oxide‐based cathodes in aqueous zinc‐ion batteries (ZIBs) depends on their crystal degree and composite state with carbon materials. Herein, an in‐situ electrochemical induction strategy was developed to fabricate MOF‐derived composite of amorphous V 2 O 5 and carbon materials (a‐V 2 O 5 @C) for the first time, where the V 2 O 5 is amorphous state and uniformly distributed in carbon framework. The amorphous structure endows V 2 O 5 with...
Tue Aug 25, 2020 19:11
Orientational control of functional molecules is essential to create complex functionalities as seen in nature; however, such artificial systems have remained challenge. Herein, we succeeded in controlling rotational isomerism of μ‐oxo silicon phthalocyanine (SiPc) oligomers to achieve an external‐stimuli‐responsive orientational ordering using intermolecular interactions of tetrathiafulvalene (TTF). In this system, three modes of orientations, free rotation, eclipsed conformation, and staggered...
Tue Aug 25, 2020 18:49
Purifying alkenes from alkanes requires cryogenic distillation. At global scale, this consumes energy equivalent to countries of ca. 5 million people. Replacing distillation with adsorption processes would significantly increase energy efficiency. Trade‐offs between kinetics, selectivity, capacity, and heat of adsorption have prevented production of an optimal adsorbent. We report adsorbents that overcome these trade‐offs. [Cu‐Br] 3 and [Cu‐H] 3 are air‐stable trinuclear complexes that undergo...
Tue Aug 25, 2020 17:29
Redox‐active esters (RAEs) as active radical precursors have been extensively studied for C‐B bond formations. However, the analogous transformations of stabilized radicals from the corresponding acid precursors remain challenging due to the strong preference towards single‐electron oxidation to the stable carbocations. This work describes a general strategy for rapid access to various aliphatic and aromatic boronic esters by mild photoinduced decarboxylative borylation. Both aryl and alkyl radicals...
Tue Aug 25, 2020 17:07
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