Temperature‐dependent ordering of colloidal zeolite LTA superballs leads three‐dimensional superstructures and chiral photonic superstructure films that can manipulate light in various ways including selective reflection of normal light, selective reflection of right‐handed circularly polarized (RCP) light, negative circular dichroism, and left‐handed circularly polarized (LCP) luminescence. Abstract Advances in zeolites research emerging from interdisciplinary efforts have opened new opportunities...
Wed Aug 19, 2020 11:30
Frustrated Lewis pair polymers can be folded into single‐chain nanoparticles by CO2 gas. The bonds of the bridging CO2 are weakened allowing direct catalytic CO2‐carboxylation of diverse C−H bonds under near atmospheric conditions. The polymers thus function as carboxylase mimics for sustainable CO2 conversion. Abstract Emulating the function of natural carboxylases to convert CO2 under atmospheric condition is a great challenge. Herein we report a class of CO2‐folded single‐chain nanoparticles...
Tue Aug 18, 2020 21:53
Conventional drug discovery approaches are difficult to apply for the removal of the misfolded protein aggregates that are thought to cause neurodegenerative disorders (NDs). In contrast, new chemical protein degradation technologies such as PROTACs seem promising for NDs therapy, opening up the possibility of selective elimination of “undruggable” target proteins by utilizing physiological protein degradation machineries. Abstract Neurodegenerative disorders (NDs) are a group of diseases...
Tue Aug 18, 2020 21:51
This year Singapore National Institute of Chemistry (SNIC) is celebrating its golden jubilee (1970–2020). Wiley‐VCH has been a steadfast partner accompanying the rapid rise of chemistry research in Singapore. In celebration of this golden jubilee, we highlight 50 significant papers published in Angewandte Chemie by scholars currently based in Singapore, covering the widest possible spectrum of chemistry research.
Tue Aug 18, 2020 21:49
In situ optical microscopy combined with atomic force microscopy studies show that the on‐site‐formed solid electrolyte interphase (SEI) shells on deposited lithium can be distinctly captured in gel polymer electrolyte based, quasi‐solid‐state lithium‐metal batteries (SSLMBs). Direct visualization of interfacial evolution of the Li dendrites and their SEI shells provides deep insights into the surface degradation and optimization in SSLMBs. Abstract Unstable electrode/solid‐state electrolyte...
Tue Aug 18, 2020 19:16
Cyclopropanated furans and pyrroles can be converted into tropanes and isoquinuclidines, featuring a 6π‐electrocyclic ring‐opening/ Huisgen [3+2]‐cycloaddition cascade of 2‐oxo‐ and 2‐aza‐bicyclo[2.1.0]‐hex‐3‐enes. Abstract The synthesis of tropanes via a microwave‐assisted, stereoselective 6π‐electrocyclic ring‐opening/ Huisgen [3+2]‐cycloaddition cascade of cyclopropanated pyrrole and furan derivatives with electron‐deficient dipolarophiles is demonstrated. Starting from furans or pyrroles,...
Tue Aug 18, 2020 19:16
Saturated bioisosteres of ortho‐disubstituted benzenes (bicyclo[2.1.1]hexanes) were synthesized, characterized and validated. These cores were incorporated into the 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. Abstract Saturated bioisosteres of ortho‐disubstituted benzenes (bicyclo[2.1.1]hexanes) were synthesized, characterized and...
Tue Aug 18, 2020 19:13
A series of soft‐matter FeII complexes displays an unusual melting‐triggered thermochromic reverse spin transition that is perfectly reproducible and can be adjusted in temperature by changing the length of aliphatic substitutes. Abstract We report a series of meltable FeII complexes, which, depending on the length of aliphatic chains, display abrupt forward low‐spin to high‐spin transition or unprecedented melting‐triggered reverse high‐spin to low‐spin transition on temperature rise....
Tue Aug 18, 2020 19:12
A photoredox/nickel dual catalyzed three‐component conjunctive cross‐coupling of alkenes with α‐silyl amines and aryl halides is reported. Primary alkyl radicals can be applied in the three‐component dicarbofunctionalization (DCF) of a π‐bond system. The base‐free, redox‐neutral conditions, the broad substrate scope, and functional group compatibility allowes to synthesize structurally valuable α‐aryl substituted γ‐amino acid moieties. Abstract A highly chemo‐ and regioselective intermolecular...
Tue Aug 18, 2020 19:11
By exploiting packing, jamming, self‐filtration, and kinetics, we developed a heat‐free biomimetic metal patterning (abbreviated BIOMAP) using delicate rose petals. Rose‐like structures, both inverse (yin/−) as well as direct (yang/+), were replicated using undercooled liquid metal core–shell particles. Textured metal patterns were created with great accuracy, and with reproducibility such that patterns from closely related cultivars can be differentiated. Both structure and wetting properties...
Tue Aug 18, 2020 19:10
The integration and encapsulation of perovskite nanocrystals into multifunctional metal–organic frameworks results in new features and paves the way to promising applications. This Minireview summarizes the recent progress of perovskite NC@MOF composites from the perspective of synthetic chemistry, functional mechanisms, and potential applications. Abstract As an emerging optical material, perovskite nanocrystals (NCs) exhibit excellent optoelectronic properties and show great potential...
Tue Aug 18, 2020 19:09
A single‐site Mo‐containing nanosized ZSM‐5 zeolite with atomically dispersed framework‐molybdenum is synthesized. The zeolite displays superior stability, maintaining the atomically dispersed Mo, structural integrity of the zeolite, and preventing the formation of silanols. Abstract The current energy transition presents many technological challenges, such as the development of highly stable catalysts. Herein, we report a novel “top‐down” synthesis approach for preparation of a single‐site...
Tue Aug 18, 2020 19:09
The new 6H hexagonal perovskite oxynitride BaWON2 is a non‐centrosymmetric polar compound that shows a total order of nitrogen and oxygen in two distinct coordination environments. The combination of anion order, electrostatic repulsion between W6+ cations, and a second‐order Jahn–Teller effect induce different distortions at three inequivalent tungsten octahedra, leading to long‐range ordered dipoles and spontaneous polarization along the c axis. Abstract Non‐centrosymmetric polar compounds...
Tue Aug 18, 2020 19:08
This Minireview describes the resistance mechanism of bacteria producing β‐lactamase and further summarize the fluorogenic probes/inhibitors of β‐lactamase, and their applications in the treatment of infectious diseases. We provide guidelines for the design of fluorogenic probes with improved selectivity/sensitivity/effectiveness to identify further inhibitors for β‐lactamases and eventually overcome bacterial resistance. Abstract β‐Lactam antibiotics are generally perceived as one of the...
Tue Aug 18, 2020 19:06
Cu nanowire arrays formed in situ are efficient catalysts for controllable deuteration of halides using D2O as a cheap and safe deuterated donor. A cross‐coupling of carbon and deuterium free radicals might be involved in this reaction. High compatibility with easily reducible functional groups, one‐pot C−H to C−D transformation, and paired synthesis of valuable chemicals at both electrodes showed the potential utility. Abstract Precise deuterium incorporation with controllable deuterated...
Tue Aug 18, 2020 19:05
A chiral diene‐rhodium complex was found to catalyze the reaction of 1,6‐enynes with ArZnCl to give high yields of 2‐(alkylidene)cyclopentylmethylzincs with high enantioselectivity (95–99 % ee). The enantioenriched alkylzincs were readily converted in a one‐pot approach into a wide variety of functionalized products by taking advantage of their unique reactivity. Abstract A chiral diene‐rhodium complex was found to catalyze the reaction of 1,6‐enynes with ArZnCl to give high yields of 2‐(alkylidene)cyclopentylmethylzincs...
Tue Aug 18, 2020 19:05
Far‐red emitting fluorescent labels are highly desirable for spectral multiplexing and deep tissue imaging. Here, we report a far‐red fluorescent chemogenetic reporter for the on‐demand imaging of fusion proteins in cells and in living multicellular organisms. Abstract Far‐red emitting fluorescent labels are highly desirable for spectral multiplexing and deep tissue imaging. Here, we describe the generation of frFAST (far‐red Fluorescence Activating and absorption Shifting Tag), a 14‐kDa...
Tue Aug 18, 2020 19:02
The structural and optical changes resulting from the interaction between a polythiophene (PTAA) and a short unlabeled peptide were exploited to develop a sensitive bacterial detection method. The method itself targets the bacteria's surface protease activity and is sensitive enough to detect 1 CFU mL−1 of E. coli in water within 6 hours. Abstract E. coli and Salmonella are two of the most common bacterial pathogens involved in foodborne and waterborne related deaths. Hence, it is critical...
Tue Aug 18, 2020 19:02
An Ir/f‐amphox‐catalyzed asymmetric hydrogenation of racemic 2,3‐syn‐dihydroxy‐1,4‐diones is presented, involving dynamic kinetic resolution to produce 1,2,3,4‐tetraols. This protocol constitutes an efficient and straightforward approach to accessing chiral sugar alcohols. The nature of the reaction was revealed as a stepwise transformation by in situ Fourier‐transform infrared spectroscopy and isolation of intermediates. Abstract An unprecedented Ir/f‐amphox‐catalyzed asymmetric hydrogenation...
Tue Aug 18, 2020 19:00
The selectivity of the methanol‐to‐olefins (MTO) reaction catalyzed by zeolites varies with cavity architecture and framework composition. The higher flexibility of the SAPO‐34 framework as compared to SSZ‐13 does not modify the relative diffusion rate of ethene and propene, but facilitates the accommodation of the bulkier cationic intermediates of the MTO reaction, increasing the production of propene and butene. Abstract The methanol‐to‐olefins reaction catalyzed by small‐pore cage‐based...
Tue Aug 18, 2020 19:00
A method for detecting electrogenerated intermediates is based on simultaneous activation of electrospray ionization and redox reaction on a wireless bipolar ultramicroelectrode. The hollow structure of the ultramicroelectrode permits rapid transferring the transient species from electrode–electrolyte interfaces into the gas phase for mass spectrometric identification on the time scale of microseconds. Abstract We report a new mass spectrometric method for detecting electrogenerated intermediates....
Tue Aug 18, 2020 19:00
A new strategy for the synthesis of cis‐decalin derivatives is realized by an asymmetric inverse‐electron‐demand Diels–Alder reaction between two different conjugate dienes. With this method, the enantioselective total synthesis of 4‐amorphen‐11‐ol and the first total synthesis of cis‐crotonin have been achieved. Abstract 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...
Tue Aug 18, 2020 18:58
Enantioselective total syntheses of post‐iboga indole alkaloids were achieved in a divergent manner. The construction of the [6.5.6.6.7]‐pentacyclic core included an asymmetric Michael/aldol cascade reaction for installing the aza[3.3.1]‐bridged cycle and an intramolecular SN2′‐type reaction for assembling the azepane ring. The stereoselective incorporation of the side chain involved a Pd‐catalyzed Stille coupling and a catalyst‐controlled hydrogenation. Abstract Divergent enantioselective...
Tue Aug 18, 2020 18:57
A general method for synthesizing plasmonic metal–metal oxide core–satellite nanostructures is reported. On these nanostructures, small metal oxide NP‐catalyzed chemical reactions can be detected by surface‐enhanced Raman spectroscopy. As a proof‐of‐concept study, oxygen vacancy sites on CuO nanoparticles are found to be very active in photooxidation reactions. Abstract This work reports on an assembling–calcining method for preparing gold–metal oxide core–satellite nanostructures, which...
Tue Aug 18, 2020 18:56
A protocol for Lewis acid‐catalyzed highly chemoselective and enantioselective reduction of 2‐vinyl‐substituted pyridines has been developed. The reactions were catalyzed by chiral spiro‐bicyclic bisboranes and occurred under mild reaction conditions with high turnover numbers. Abstract Herein, we report that highly chemoselective and enantioselective reduction of 2‐vinyl‐substituted pyridines has been achieved for the first time. The reaction, which uses chiral spiro‐bicyclic bisboranes...
Tue Aug 18, 2020 18:56
A modular approach to access dibenzo‐fused ϵ‐lactams through palladium‐catalyzed bridging‐C−H activation is described. The reaction employs easily accessible chemicals as reactants and displays broad substrate scope with good functional‐group compatibility. The synthetic utility of this method is demonstrated by the collective synthesis of nine biologically active molecules. Abstract Tricyclic ring systems possessing a dibenzo structure joined to a seven‐membered heterocyclic ring frequently...
Tue Aug 18, 2020 18:54
The first general approach to the formation of enantioenriched cyclopropanone equivalents is reported by the α‐hydroxylation of sulfonylcyclopropanes, giving access to a wide variety of highly reactive and modular reagents suitable for ring‐expansion processes. Exemplified here is the formation of chiral β‐lactams by a formal [3+1] cycloaddition using simple hydroxylamines as nitrene sources. Abstract Cyclopropanone derivatives have long been considered unsustainable synthetic intermediates...
Tue Aug 18, 2020 18:54
Strong upconversion luminescence at 780 nm can be observed under ambient conditions after photoexcitation at 980 nm in a new ionic solid consisting of discrete YbIII‐ and CrIII‐complexes. The upconversion process is insensitive to atmospheric oxygen and can be observed in the presence of water molecules in the crystal lattice Abstract Upconversion photoluminescence in hetero‐oligonuclear metal complex architectures featuring organic ligands is an interesting but still rarely observed phenomenon,...
Tue Aug 18, 2020 18:54
A new organocatalytic cascade process converts alcohol‐functionalized five‐membered cyclic carbonates into six‐membered analogues using organocatalysis at room temperature. This methodology delivers a wide range of elusive, substituted CO2‐based heterocycles in good yields. The chemoselectivity is kinetically controlled, offering a unique manifold to forge larger‐ring cyclic organic carbonates. Abstract A conceptually novel approach is described for the synthesis of six‐membered cyclic...
Tue Aug 18, 2020 18:51
Mn and Na additives have been widely studied for improving the efficiency of CO 2 hydrogenation to valuable olefins on Fe catalysts, but their effects on the catalytic properties and mechanism are still under vigorous debate. This study shows that Fe‐based catalysts with moderate Mn and Na contents are highly selective for CO 2 hydrogenation to olefins, together with low selectivities both to CO and CH 4 and much improved space‐time olefin yields compared to those state‐of‐the‐art catalysts....
Tue Aug 18, 2020 18:05
Conventional carbonate solvents with low HOMO levels are theoretically compatible with the low‐cost, high‐voltage Zn/graphite battery chemistry. However, the anion nucleophilic attack on carbonates induces the oxidative breakdown at high potentials. Here, we restore the inherent anodic stability of carbonate electrolytes by designing a micro‐heterogeneous anion solvation network. Based on the addition of a strongly electron‐donating trimethyl phosphate (TMP) solvent, the oxidation‐vulnerable anion‐carbonate...
Tue Aug 18, 2020 17:59
Organic electrode materials are suffering from the low electronic conductivity and poor structure stability. Herein, a metal‐organic polymer, Ni coordinated tetramino‐benzoquinone (Ni‐TABQ), is synthesized via d‐π hybridization, the polymer chains of which are stitched by hydrogen bonds to feature as a robust two‐dimensional (2D) layered structure. It offers both electron conduction and Na + diffusion pathways along the directions of the polymer chains and the hydrogen bonds. With both the conjugated...
Tue Aug 18, 2020 16:59
<p class="Standard"><span lang="EN‐US" style="color:black">Advanced applications of the Nobel Prize winning olefin metathesis reaction requires user‐friendly and highly universal catalysts. From many successful metathesis catalysts, belonging to two distinct classes of Schrock and Grubbs type catalysts, the sub‐class of the chelating‐benzylidene ruthenium complexes (so‐called Hoveyda‐Grubbs catalysts) additionally activated by Electron Withdrawing Groups (EWGs) provided a highly tunable...
Tue Aug 18, 2020 12:30
Drawn to the blood: When benzene‐1,3,5‐tricarboxamide 1D fibers are decorated with benzoxaborole moieties, a dynamic interaction with human red blood cells is induced via the adaptive covalent reaction between boronic acids and cell sialic acids. Total internal reflection fluorescence microscopy is exploited as powerful tool to allow real‐time imaging of cells/fiber binding, revealing the multivalency of this interaction. Abstract Understanding cell/material interactions is essential to...
Tue Aug 18, 2020 11:10
The nonadride natural product (+)‐cornexistin was synthesized through sequential fragment coupling. The developed strategy installs the crucial stereocenters at an early stage and features a powerful intramolecular alkylation reaction to forge the nine‐membered carbocycle. The synthesis provided more than 150 mg of the target compound. Abstract Herein, we describe the first total synthesis of (+)‐cornexistin as well as its 8‐epi‐isomer starting from malic acid. The robust and scalable route...
Tue Aug 18, 2020 11:10
Water, nitrogen, and carbon dioxide are “magic” molecules whose efficient electrocatalytic conversion into suitable energy can deliver limitless renewable energy. Discussed in this Minireview are the key fundamental and experimental factors that aid in the understanding of the dynamic nature of active sites, reaction kinetics, and mechanisms, as well as selectivities and catalyst stabilities on a molecular level. Abstract The use of renewable energy by means of electrochemical techniques...
Tue Aug 18, 2020 11:10
A pair of hollow carbon sphere (HCS) nanoreactors with PdCu nanoparticles encapsulated inside the HCS (PdCu@HCS) and supported outside the HCS (PdCu/HCS) have been prepared. Based on the two comparable systems, the void‐confinement effects of hollow nanoreactors in liquid‐phase hydrogenation have been extensively investigated in a two‐chamber reactor. Abstract Nanoreactors with hollow structures have attracted great interest in catalysis research due to their void‐confinement effects. However,...
Tue Aug 18, 2020 11:08
The calix[4]pyrrolato aluminate enables a transfer of metal–ligand cooperativity from the d‐ into the p‐block. The compound traps carbonyls and delivers products that are showing highly dynamic–covalent behavior. Lithium ions provide full control over the formation and cleavage of C−C bonds. The adjustability in substrate activation enables a unique concept for rate control in catalysis. Abstract Metal‐ligand cooperativity (MLC) had a remarkable impact on transition metal chemistry and...
Tue Aug 18, 2020 11:07
We report a new air‐stable Pd(I) dimer, i.e. [Pd(μ‐I)(PCy 2t Bu)] 2 that triggers E‐selective olefin migrations to enamides and styrene derivatives in the presence of multiple functional groups and under complete tolerance of air. The same dimer also triggers extremely rapid C‐C couplings (alkylation and arylation) at room temperature in a modular and triply selective fashion of aromatic C‐Br, C‐OTf/OFs and C‐Cl bonds in poly(pseudo)halogenated arenes, displaying superior activity over previous...
Tue Aug 18, 2020 11:00
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