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. Herein, we employed a simple pH‐modulated method for in‐situ growth of FeNi oxyhydroxide ultrathin‐layers on BiVO 4 photoanodes, resulting in one of the highest currently known PEC activities of 5.8 mA cm −2 (1.23 V RHE , AM 1.5G) accompanied with an excellent stability. More importantly,...
Tue Jul 14, 2020 18:01
A series of assembled Pt(II) complexes comprising N‐heterocyclic carbene and cyanide ligands was constructed using different substituent groups, [Pt(CN)2(R‐impy)] (R‐impyH+ = 1‐alkyl‐3‐(2‐pyridyl)‐1H‐imidazolium, R = Me (Pt‐Me), Et (Pt‐Et), iPr (Pt‐ iPr), and tBu (Pt‐ tBu )). All the complexes exhibited highly efficient photoluminescence with an emission quantum yield of 0.51–0.81 in the solid state at room temperature, originating from the triplet metal‐metal‐to‐ligand charge transfer (3MMLCT)...
Tue Jul 14, 2020 18:01
Rapid synthesis of marine ladder polyethers from polyepoxide precursors (in analogy with the biosynthetic pathway hypothesized by Nakanishi) is hampered by the fact that the exo ‐selective epoxide‐opening cyclization cascade that gives THF‐type polyethers is preferred over the endo ‐selective cascade that gives the desired products. We found that perfluoro‐ tert ‐butanol (PFTB) cooperates with 1‐ethyl‐3‐methylimidazolium tetrafluoroborate ([EMIM]BF 4 ) can promote endo ‐selective epoxide‐opening...
Tue Jul 14, 2020 17:55
A non‐conjugated polymer acceptor PF1‐TS4 was firstly synthesized by embedding a thioalkyl segment in the mainchain, which presents excellent photophysical properties like a fully conjugated polymer with a low optical bandgap of 1.58 eV and a high absorption coefficient of 1.28 × 10 5 cm ‐1 , a high LUMO level of ‐3.89 eV, and suitable crystallinity. Matched with a polymer donor PM6, the PF1‐TS4‐based all‐PSC achieved a power conversion efficiency (PCE) of 8.63%, which is ~1.5 times higher than...
Tue Jul 14, 2020 16:55
High propylene selectivity during oxidative dehydrogenation catalyzed by hexagonal boron nitride originates from surface‐initiated radical reactions that propagate via gas‐phase chemistry. This reaction network contrasts with previously studied vanadium‐based catalysts where surface reactions predominate and lower selectivity. An experimental and computational approach was used to probe this complex surface–gas‐phase reaction network. Abstract Boron‐containing materials, and in particular...
Tue Jul 14, 2020 22:00
The current COVID‐19 pandemic has a tremendous impact on daily life world‐wide. Despite the ability to dampen the spread of SARS‐CoV‐2, the causative agent of the diseases, through restrictive interventions, it is believed that only effective vaccines will provide sufficient control over the disease and revert societal live back to normal. At present, a double‐digit number of efforts are devoted to the development of a vaccine against COVID‐19. Here, we provide an overview of these (pre)clinical...
Tue Jul 14, 2020 21:24
Quinolactacins are novel fungal alkaloids that feature a quinolone‐ γ ‐lactam hybrid, which is a potential pharmacophore for the treatment of cancer and Alzheimer’s disease. Here, we report the identification of the quinolactacin A2 biosynthetic gene cluster and elucidate the enzymatic basis for the formation of the quinolone‐ γ ‐lactam structure. We reveal an unusual β ‐keto acid ( N ‐methyl‐2‐aminobenzoylacetate) precursor that is derived from the primary metabolite L‐kynurenine via methylation,...
Tue Jul 14, 2020 19:55
Selective probing of neurochemicals is essential for understanding the chemical basis of brain function and pathology. To this aim, interfacing excellent recognition features of aptamers with in vivo compatible carbon fiber microelectrode (CFE)‐based electroanalytical system offers a plausible means, however, is significantly challenged in terms of coupling chemistry, stability, and versatility. Here, we present a new interfacial functionalization strategy created through the assembly of aptamer...
Tue Jul 14, 2020 18:25
The Pseudomonas virulence factor ( pvf ) operon is essential for the biosynthesis of two very different natural product scaffolds: the (dihydro)pyrazine‐ N‐ oxides and the diazeniumdiolate, valdiazen. PvfB is a member of the non‐heme diiron N ‐oxygenase enzyme family that commonly convert anilines to their nitroaromatic counterparts. In contrast, we show that PvfB catalyzes N‐ oxygenation of the α‐amine of valine, first to the hydroxylamine and then the nitroso, while linked to the carrier...
Tue Jul 14, 2020 17:54
Selective cleavage and functionalization of C‐C bonds have important applications in organic synthesis and biomass utilization. However, functionalization of C‐C bonds by controlled cleavage remains difficult and challenging because they are inert. Herein, we describe an unprecedented efficient protocol for the breaking of successive C‐C bonds in alcohols to form esters with one or multiple carbon atoms less using heterogeneous cobalt nanoparticles catalyst with dioxygen as the oxidant. A wide range...
Tue Jul 14, 2020 15:23
An inexpensive new reagent enables the development of metal‐free protocols for stereodivergent hydrofluorination. Computations and mechanistic data support the intermediacy of vinyl cations, which are trapped to deliver E‐ and Z‐vinyl fluorides under kinetic and thermodynamic control, respectively. Abstract The discovery of safe, general, and practical procedures to prepare vinyl fluorides from readily available precursors remains a synthetic challenge. The metal‐free hydrofluorination...
Tue Jul 14, 2020 14:08
It is of great significance to track the platinum drugs in real time with super‐resolution to elucidate their mechanism of action, such as their behavior and distribution in live cells, for drug development. However, it is always challenging to design platinum complexes suitable for such research. Here, we design a luminescent building block ( L ) for metal complexes and a dinuclear platinum complex ( Pt 2 L ) for super‐resolution imaging. Because of its super‐large Stokes shift and excellent...
Tue Jul 14, 2020 13:54
Hydrogen‐transfer in the tetrahedral intermediate generated from an imidazolylidene catalyst and α,β‐unsaturated aldehyde forms a conjugated Breslow intermediate. This is a critical step affecting the efficiency of the NHC‐catalyzed γ‐butyrolactone formation via homoenolate addition to aryl aldehydes. A novel type of imidazolylidene catalyst with pendant alkoxy groups on the ortho‐N‐aryl groups is described. Catalyst of this sort facilitates the formation of the conjugated Breslow intermediate. Studies...
Tue Jul 14, 2020 12:25
Ambient temperature ruthenium‐catalyzed C–H arylations were accomplished by visible light without additional photocatalysts. The robustness of the ruthenium‐catalyzed C–H functionalization protocol was reflected by a broad range of sensitive functional groups and synthetically useful pyrazoles, triazoles and sensitive nucleosides and nucleotides, as well as multifold C–H functionalizations. Biscyclometalated ruthenium complexes were identified as the key intermediates in the photoredox ruthenium...
Tue Jul 14, 2020 12:23
Narrow HOMO‐LUMO gaps and high charge carrier mobilities make larger acenes potentially high‐efficient materials for organic electronic applications. The performance of such molecules was shown to significantly increase with increasing number of fused benzene rings. Bulk quantities, however, can only be obtained reliably for acenes up to heptacene. Theoretically, (oligo)acenes and (poly)acenes are predicted to possess open‐shell singlet biradical and polyradical ground states, respectively, for which...
Tue Jul 14, 2020 12:44
Saturated mimetics for ortho ‐disubstituted benzenes ‐ bicyclo[2.1.1]hexanes, ‐ were synthesized, characterized and validated. These cores were incorporated into bioactive compounds Valsartan, Boskalid and Fluxapyroxad instead of the benzene ring. The saturated analogues showed a similar level of antifungal activity compared to that of Boskalid and Fluxapyroxad .
Tue Jul 14, 2020 12:44
Herein we report photoinitiated polymerization‐induced self‐assembly (photo‐PISA) of spherical micelles consisting of proapoptotic peptide‐polymer amphiphiles. The one‐pot synthetic approach yielded micellar nanoparticles at high concentrations and at scale (150 mg/mL) with tunable peptide loadings up to 48 wt. %. The size of the micellar nanoparticles was tuned by varying the lengths of hydrophobic and hydrophilic building blocks. Critically, the peptide‐functionalized nanoparticles imbued the proapoptotic...
Mon Jul 13, 2020 22:55
Zeolite reactivity depends on the solvating environments of their micropores and the proximity of their Brønsted acid sites. Turnover rates (per H+) for methanol and ethanol dehydration increase with the fraction of H+ sites sharing six‐membered rings of chabazite (CHA) zeolites. DFT shows that activation barriers vary widely with the number and arrangement of Al (1‐5 per 36 T‐site unit cell), but cannot be described solely by Al–Al distance or density. Certain Al distributions yield rigid arrangements...
Mon Jul 13, 2020 22:25
Branched nickel nanoparticles having controlled branch length are synthesized using a new approach. The branches enable high surface area and surface facets which improve the catalytic activity for biomass electrooxidation. Abstract Controlling the formation of nanosized branched nanoparticles with high uniformity is one of the major challenges in synthesizing nanocatalysts with improved activity and stability. Using a cubic‐core hexagonal‐branch mechanism to form highly monodisperse branched...
Mon Jul 13, 2020 22:00
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 self‐powered devices, which can be operated in the absence of external bias. Herein, for the first time, ferroelectricity‐driven self‐powered photodetection towards polarized UV light was successfully demonstrated in a 2D wide‐bandgap hybrid ferroelectric (BPA) 2 PbBr...
Mon Jul 13, 2020 21:24
Two new quantum defects were incorporated into single‐walled carbon nanotubes (SWCNT) carrying anchor groups for functionalization with biomolecules. The potential and versatility of this approach was demonstrated by the conjugation of a GFP‐binding nanobody as well as the growth of (fluorescent) peptide chains directly on the nanotube's carbon lattice. Abstract Single‐walled carbon nanotubes (SWCNTs) are a 1D nanomaterial that shows fluorescence in the near‐infrared (NIR, >800 nm)....
Mon Jul 13, 2020 21:00
Taking charge : A nickel (Ni) electron acceptor has been successfully doped into a Cu2O lattice without forming impurity phases. Both theoretical and experimental results demonstrate that Ni dopants attract electrons from neighboring atoms, therefore facilitating charge separation and transfer. Consequently, the obtained Ni‐Cu2O exhibits a significantly enhanced photoelectrochemical performance. Abstract Cu2O is a typical photoelectrocatalyst for sustainable hydrogen production, while the...
Mon Jul 13, 2020 20:59
Coupled complex : A novel crystalline proton–electron coupling system was developed using an iron(II) hydrazone complex. The complex exhibits a thermally and photoinduced proton‐transfer‐coupled spin transition. The intermediate phase has two types of iron(II) complexes with distinct spin states and proton positions. The proton transfer in one of the two ligands changes the direction and magnitude of the molecular dipole moment. Abstract A proton–electron coupling system, exhibiting unique...
Mon Jul 13, 2020 20:59
Quantitative generation of hetero‐chromophore dimers is realized through cucurbit[8]uril‐directed self‐sorting, favored by the introduction of designed, shape‐complementary moieties. This process results in discrete heterodimeric stacking through supramolecular confinement, enabling efficient interchromophoric energy transfer upon photoexcitation. Abstract The challenge of quantitatively forming self‐assembled heterodimers without other equilibrium by‐products is overcome through self‐sorting...
Mon Jul 13, 2020 20:58
Triple threat : A mitochondria‐targeting probe switches on in three different fluorescence modes in response to H2O2, protein, and nucleic acids, enabling the visualization of mitochondrial nucleoprotein dynamics. Super‐resolution imaging reveals that the proteins localize at mitochondrial cristae and largely fuse with nucleic acids to form nucleoproteins, whereas increasing H2O2 levels lead to disassociation of the nucleoproteins. Abstract Understanding the biomolecular interactions in...
Mon Jul 13, 2020 20:58
An old phenomenon in a new light : In this brief Essay, the currently highly recognized aggregation‐induced emission (AIE) phenomenon is discussed in a broader perspective by illustrating its roots in earlier work. Abstract Aggregation‐induced emission (AIE) has attracted considerable interest over the last twenty years. In contrast to the large number of available reviews focusing specifically on AIE, this Essay discusses the AIE phenomenon from a broader perspective, with an emphasis...
Mon Jul 13, 2020 20:57
Pumping electrons to produce fuel : A fully π‐conjugated 2D covalent organic framework with aligned metallophthalocyanine electrocatalytic sites enable electron pumping to CO2 reduction centers. The 2D π lattice catalyzes two‐electron reduction of CO2 to CO in water to achieve an exceptional turnover number up to 320 000 hour−1 and a faraday efficiency of 96 %. Abstract Transformation of carbon dioxide to high value‐added chemicals becomes a significant challenge for clean energy studies....
Mon Jul 13, 2020 20:57
MnOx nanospikes serve as tumor microenvironment‐responsive nanoadjuvants and immunogenic cell death drugs for cancer nanovaccine‐based immunotherapy. They induce immunogenic cell death via chemodynamic therapy and ferroptosis, thereby enhancing antitumor immunity and antimetastatic effect. Key: glutathione (GSH), glutathione peroxidase 4 (GPX4), magnetic resonance imaging (MRI), near infrared (NIR), photoacoustic imaging (PAI). Abstract Despite the widespread applications of manganese...
Mon Jul 13, 2020 20:56
“The most exciting thing about research is the freedom to explore uncharted territory. The best advice I have ever been given is that good research is driven by a hypothesis … ” Find out more about Andreas Walther in his Author Profile.
Mon Jul 13, 2020 20:54
“My favorite saying is ‘diamonds are created under pressure’. … My first experiment was to blow up a tin can using a mixture of sugar and saltpeter . …” Find out more about Berthold Hoge in his Author Profile.
Mon Jul 13, 2020 20:53
A key current challenge in biological research is the elucidation of the that roles chemicals and chemical reactions play in cellular function and dysfunction. Of the available cellular imaging techniques, fluorescence imaging offers a balance between sensitivity and resolution, enabling the cost‐effective and rapid visualisation of model biological systems. Importantly, the use of responsive fluorescent probes in conjunction with ever‐advancing microscopy and flow cytometry techniques enables the...
Mon Jul 13, 2020 20:50
Reported here is a synergistic enhancement strategy for realizing ultralong bright room‐temperature phosphorescence (RTP), involving polymerization between phosphor monomers and acrylamide and host‐guest complexation interaction between phosphors and cucurbit[6, 7, 8]urils (CB[6, 7, 8]). The non‐phosphorescent monomers exhibit 2.46 s ultralong lifetime after copolymerizing with acrylamide. The immense improvement is because of the rich hydrogen bond and carbonyl within the polymers which promote...
Mon Jul 13, 2020 20:31
Precise deuterium incorporation with controllable deuterated sites and amount is extremely desirable. Here, a facile and efficient electrocatalytic deuterodehalogenation of halides using heavy water (D 2 O) as the deuteration reagent and electrochemical in situ formed copper nanowire arrays (Cu NWAs) as the cathode was demonstrated. A cross‐coupling of carbon and deuterium free radicals might be involved for this ipso‐selective deuteration. This method exhibited excellent chemoselectivity and high...
Mon Jul 13, 2020 20:30
Metal node design is crucial for obtaining structurally diverse coordination polymers (CPs) and metal‐organic frameworks with desirable properties; however, Fe(II) ions are exclusively six‐coordinated. Herein, we present a cyanide‐bridged three‐dimensional (3D) CP, FePd(CN)4, bearing four‐coordinate Fe(II) ions, which is synthesized by thermal treatment of a two‐dimensional (2D) six‐coordinate Fe(II) CP, Fe(H2O)2Pd(CN)4·4H2O, to remove water molecules. Atomic‐resolution transmission electron microscopy...
Mon Jul 13, 2020 19:18
A novel strategy for the synthesis of cis‐decalins by an ytterbium‐catalyzed asymmetric inverse‐electron‐demand Diels–Alder reaction of 2‐pyrones and silyl cyclohexadienol ethers is reported here. A broad range of synthetically important cis‐decalin derivatives with multiple contiguous stereogenic centers and functionalities are obtained in good yields and stereoselectivities. A full set of diastereomeric substituted cis‐decalin motifs are readily accessible by tuning the absolute configurations...
Mon Jul 13, 2020 18:30
Traditionally, lots of experiments are needed to optimize the performance of membrane electrode assembly (MEA) in proton exchange membrane fuel cells (PEMFCs) since it involves complex electrochemical, thermodynamic and hydrodynamic processes. Herein, we introduce artificial intelligence (AI)‐aided models for the first time to determine key parameters for nonprecious metal electrocatalyst‐based PEMFC, thus reducing unnecessary experiments during MEA development. Among 16 competing algorithms widely...
Mon Jul 13, 2020 17:59
Carbonyl compounds (R 2 C=O) are cornerstones of organic chemistry. In sharp contrast, main group carbonyl analogues (R 2 E=O) derived from p ‐block elements from groups 13 to 15, have long been considered to be elusive species. Employment of chemical tricks such as acid/base stabilization protocols granted access to these transient species in their masked forms. However, electronic and steric effects inevitably perturb their chemical reactivity and distinguish them from classical carbonyl...
Mon Jul 13, 2020 17:09
The first Cope Award was presented in 1973 to R. B. Woodward and Roald Hoffmann (the only shared Cope Award). In his award lecture, Woodward described his fascination in his early teens with the Diels‐Alder reaction. Beginning in the late 1930s with his B.S. and Ph.D. theses and extending throughout his career, Woodward studied the mechanism of the Diels‐Alder reaction and used it extensively in his total syntheses. This article describes the evolution of Woodward’s mechanistic thinking, beginning...
Mon Jul 13, 2020 17:09
A novel [4+1] spiroannulation of o‐ & p‐bromophenols with α,β‐unsaturated imines has been developed for the direct synthesis of a new family of azaspirocyclic molecules. Notably, several other halophenols (X = Cl, I) were also applicable for this transformation. Moreover, a catalytic asymmetric version of the reaction was realized with 1‐bromo‐2‐naphthols by using a chiral Sc(III)/Py‐Box catalyst. Mechanistic studies revealed that this domino reaction proceeded through electrophile‐triggered...
Mon Jul 13, 2020 17:08
Our conceived approach based on the directed assembly of functional metal‐organic squares (MOSs), 4‐membered ring (4MR) building units, permitted the construction of two novel zeolite‐like supramolecular assemblies (ZSAs), namely [Co 4 (ImDC) 4 (En) 4 ]·9H 2 O·1.5DMF ( ZSA‐10 ) and [Co 4 (ImDC) 4 (En) 4 ]·7H 2 O ( ZSA‐11 ) (H 3 ImDC = 4,5‐imidazoledicarboxylic acid, En = ethylenediamine, DMF = N,N‐dimethylformamide). The elected MOSs encompass both trans ‐ and cis ‐coordinated...
Mon Jul 13, 2020 17:08
Engineering T lymphocytes is an emerging approach in a variety of biomedical applications. However, delivering large biologics to primary T lymphocytes directly in vivo is technically challenging due to the low transfection efficacy. In this paper, we investigated a library of synthetic lipid‐like molecules (lipidoids) for their capability of delivering mRNA into primary T lymphocytes both ex vivo and in vivo . We initially conducted a library screening with large structural variety of lipidoids...
Mon Jul 13, 2020 17:08
Metalation of functionalized (hetero)arenes with KDA (potassium diisopropylamide)/TMEDA to give the corresponding potassium organometallics was performed using a commercial continuous flow set‐up. In their Communication on https://doi.org/10.1002/anie.202003392page 12321, P. Knochel et al. show that trapping with various electrophiles gives polyfunctionalized (hetero)aromatics in good yields. The flow procedure was extended to the lateral metalation of methyl‐substituted (hetero)arenes resulting...
Mon Jul 13, 2020 12:29
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