Thermally activated delayed fluorescence (TADF) is generally observed in solid‐state organic molecules or metal‐organic complexes. However, TADF in all‐inorganic colloidal nanocrystals (NCs) is rare. Herein, we report the first colloidal synthesis of an air‐stable all‐inorganic lead‐free Cs 2 ZrCl 6 perovskite NCs. The Cs 2 ZrCl 6 NCs exhibit long‐lived triplet excited state (138.2 μs), featuring highly efficient photoluminescence (PL) quantum efficiency (QY= 60.37%) due to TADF. The emission...
Sat Aug 22, 2020 17:54
We demonstrate an intermolecular reaction cascade to control the force which triggers crosslinking of a mechanochromic polymer of spirothiopyran (STP). Mechanochromism arises from rapid reversible force‐sensitive isomerization of STP to a merocyanine, which reacts rapidly with activated C=C bonds. The concentration of such bonds, and hence the crosslinking rate, is controlled by force‐dependent dissociation of a Diels‐Alder adduct of anthracene and maleimide. Because the adduct requires ~1 nN higher...
Sat Aug 22, 2020 17:13
Electrostatic interactions can strongly increase the efficiency of protein complex formation. The charge distribution in redox proteins is often optimized to steer a redox partner to the electron transfer active binding site. To test whether the optimized distribution is more important than the strength of the electrostatic interactions, an additional negative patch was introduced on the surface of cytochrome c peroxidase, away from the stereospecific binding site, and its effect on the encounter...
Sat Aug 22, 2020 11:59
Triarylsilanolates are privileged ancillary ligands for molybdenum alkylidyne catalysts for alkyne metathesis but lead to disappointing results and poor stability in the tungsten series. 1H,183W Heteronuclear Multiple Bond Correlation (HMBC) spectroscopy exploiting a favorable 5J‐coupling between the 183W center and the peripheral protons on the alkylidyne cap revealed that these ligands upregulate the Lewis‐acidity to an extent that the tungstenacyclobutadiene formed in the initial [2+2] cycloaddition...
Fri Aug 21, 2020 22:00
90% Quantum Yield Pure‐Red Doublet Emission from Stable, Colorless, Iodinated Triphenylmethane Solid
We report red luminescence in off‐white tris(iodoperchlorophenyl)methane (3I‐PTMH) crystals which is characterized by high photoluminescence quantum yield (PLQY 91%) and color purity (CIE coordinates 0.66, 0.34). The emission originates from the doublet excited state of the neutral radical 3I‐PTMR that is spontaneously formed and becomes embedded in 3I‐PTMH matrix. The radical defect can also be deliberately introduced in 3I‐PTMH crystals which maintain high PLQY up to 4% radical concentration. The...
Fri Aug 21, 2020 21:43
Selenium NMR has become a standard tool for scaling the π‐accepting character of carbenes. Herein, we highlight that non‐classical hydrogen bonding (NCHB), likely resulting from hyperconjugation, can play a significant role in the carbene‐selenium 77Se NMR chemical shift, thus triggering a non‐linear behaviour of the Se‐Scale.
Fri Aug 21, 2020 20:15
Synthesizing a wide variety of single‐atom catalysts (SACs) on different supports via a universal strategy is still challenging because of the high surface energy of single atoms which leads to serious aggregation. Here we report a general graphene quantum dot‐tethering design strategy to synthesize SACs. The strategy is applicable to different metals (Cr, Mn, Fe, Co, Ni, Cu and Zn) and supports (0D carbon nanosphere, 1D carbon nanotube, 2D graphene nanosheet, and 3D graphite foam) with the metal...
Fri Aug 21, 2020 17:44
Polysulfide intermediates (PSs), the liquid‐phase species of active materials in lithium–sulfur (Li–S) batteries, connect the electrochemical reactions between insulative solid sulfur and lithium sulfide and are regarded as the key to full exertion of the high‐energy‐density Li–S system. To manipulate the reactivity and distribution of PSs is one of the most important targets to enhance the performances of Li–S batteries. Compared with the exploration of extrinsic regulations such as physical confinement...
Fri Aug 21, 2020 17:28
Atomically precise tailoring of interface structures is crucial for developing functional materials. We demonstrate an N‐heterocyclic carbene (NHC) based molecular tool, which modifies the structure of a gold surface with atomic accuracy by the formation of gold nanorods. After adsorption on the gold surface, individual surface atoms are pulled out by the NHCs, generating single‐atom surface defects and mobile NHC‐Au species. Atomistic calculations reveal that these molecular ballbots can act as...
Fri Aug 21, 2020 17:10
Atomically dispersed and nitrogen coordinated single metal sites (M‐N‐C, M=Fe, Co, Ni, or Mn) are the popular platinum group‐metal (PGM)‐free catalysts for many electrochemical reactions. Traditional wet‐chemistry catalyst synthesis often requires complex procedures with unsatisfied reproducibility and scalability. Here, we report a chemical vapor deposition (CVD) strategy to synthesize the promising single metal site (M‐N‐C) catalysts. The deposition of gaseous 2‐methylimidazole onto ZnO substrates...
Fri Aug 21, 2020 15:10
Low initial Coulombic efficiency (ICE) is one of the most obstacles for practical application of Li‐rich Mn‐based layered oxides (LLOs), which is closely related with the irreversible oxygen evolution due to the overoxidized reaction of surface labile oxygen. Here we report a NH4F‐assisted surface multicomponent integration technology to accurately control the ICE, by which oxygen vacancies, spinel‐layered coherent structure and F‐doping are skillfully integrated on the surface of treated LLOs microspheres....
Fri Aug 21, 2020 13:39
Transmembrane protein channels are of primordial inspiration for the design of artificial ion channels. Their dipolar structure helps overcome the high energy barrier to selectively translocate water and ions sharing one pathway, across the cell membrane. Particularly interesting, the alignment of ion and water molecules imposed by the pore structure can control the ionic conduction. Herein, we report that the amino‐imidazole (Imu) amphiphiles self‐assemble via multiple H‐bonding to form stable artificial...
Fri Aug 21, 2020 13:14
Lithium phosphorus oxynitride (LiPON) is an amorphous solid‐state lithium ion conductor displaying exemplary cyclability against lithium metal anodes. There is no definitive explanation for this stability due to the limited understanding of the structure of LiPON. We provide a structural model of RF‐sputtered LiPON via experimental and computational spectroscopic methods. Information about the short‐range structure results from 1D and 2D solid‐state nuclear magnetic resonance experiments investigating...
Thu Aug 20, 2020 22:33
Zusammenfassung Das Bestreben aus CO 2 mittels katalytischer Reduktion Wertstoffe zu gewinnen und damit einen Beitrag zur Bekämpfung der Treibhausgasemissionen zu leisten, führt zu enormen Anstrengungen der chemischen Forschung. Die Dimensionen von Energiesystemen auf der einen Seite und der notwendige Transport und Handel mit global gewonnenen erneuerbaren Energien auf der anderen Seite werden den Einsatz von chemischen Batterien neben der lokalen Gewinnung von erneuerbarer Energie als elektrischem...
Thu Aug 20, 2020 22:00
High temperature treatment of γ‐Al 2 O 3 can lead to a series of polymorphic transformations, including the formation of δ‐Al 2 O 3 and θ‐Al 2 O 3 . Quantification of the microstructure in the range where δ‐ and θ‐Al 2 O 3 are formed represents a formidable challenge as both phases accommodate a high degree of structural disorder. In this work, we explore the use of an XRD recursive stacking formalism for quantification of high temperature transition aluminas. We formulate the recursive...
Thu Aug 20, 2020 21:41
A quasi Mars–van Krevelen surface reaction mechanism involving withdrawal and regenerating surface carbon atom during nonoxidative catalytic conversion of methane on Fe1©SiC2 is presented. Abstract The direct, nonoxidative conversion of methane on a silica‐confined single‐atom iron catalyst is a landmark discovery in catalysis, but the proposed gas‐phase reaction mechanism is still open to discussion. Here, we report a surface reaction mechanism by computational modeling and simulations....
Thu Aug 20, 2020 21:16
The unconventional spherical assembly of discotic perylene bisimides (PBIs), as opposed to common columnar assembly, was successfully achieved by the incorporation of bulky units at the periphery. The peripheric steric hindrance can be tuned by varying the linkage structures, resulting in diverse spherical supramolecular structures in PBIs. Abstract Like other discotic molecules, self‐assembled supramolecular structures of perylene bisimides (PBIs) are commonly limited to columnar or lamellar...
Thu Aug 20, 2020 21:16
The novel pharmacophore quinolone‐γ‐lactam hybrid is constructed via the condensation of an unnatural and unstable β‐keto acid with isoleucine, catalyzed by two non‐ribosomal peptide synthetases. Most intriguingly, this β‐keto acid was biosynthesized from tryptophan via extensive modifications catalyzed by a dedicated set of enzymes, which represents a new strategy used by nature to generate structural complexities. Abstract Quinolactacins are novel fungal alkaloids that feature a quinolone‐γ‐lactam...
Thu Aug 20, 2020 21:15
Various aromatic polyketides were prepared from macrocyclic substrates by catalyst‐controlled transannular cyclization cascades. The high stability of the macrocyclic polyketides enabled the control of the folding and oxygenation pattern by using small‐molecule catalysis. The synthesis of several distinct cyclization products from common precursors highlights the virtues of divergent catalysis and regioselective reaction cascades. Abstract The biomimetic synthesis of aromatic polyketides...
Thu Aug 20, 2020 21:15
Spatiotemporal delivery of CRISPR/Cas9 genome editing machinery is of great importance for developing chemical biology tools for manipulating cellular DNA sequences to treat genetic disorders. This Minireview provides an overview of synthetic approaches and specific chemistries that have been used to develop stimuli‐responsive vehicles for CRISPR/Cas9 delivery and genome editing in a controlled manner. Abstract Recent innovations in genome editing have enabled the precise manipulation of...
Thu Aug 20, 2020 21:14
Cucurbit[8]uril can stabilize discrete host:guest n:n oligomers of controlled size and shape in water with properties specific to the oligomers. We collected more than 50 examples and identified several factors explaining the formation of linear or cyclic oligomers and provide some rational to design new assemblies and target advanced properties. Abstract Proteins are an endless source of inspiration. By carefully tuning the amino‐acid sequence of proteins, nature made them evolve from...
Thu Aug 20, 2020 21:14
Two in one: A photoinduced asymmetric radical decarboxylative alkynylation of bench‐stable racemic carboxylic acid derivatives with easily available terminal alkynes provides expedient access to diverse enantioenriched alkynes. The chiral copper catalyst serves as a dual photo‐ and cross‐coupling catalyst to achieve stereocontrol over the highly reactive prochiral alkyl radical intermediates. Abstract We describe a photoinduced copper‐catalyzed asymmetric radical decarboxylative alkynylation...
Thu Aug 20, 2020 21:14
Thanks to their predesigned structure, intrinsic porosity and decent conductivity, 2D c‐MOFs have attracted considerable attention especially in electrochemical energy storage. In this Minireview, the progress of 2D c‐MOFs is surveyed with a focus on the structural design principles, electrical properties and potential applications in supercapacitors and batteries. Abstract Two‐dimensional conductive metal–organic frameworks (2D c‐MOFs) as an emerging class of multifunctional materials...
Thu Aug 20, 2020 21:09
The natural tRNA modification i6A carries an isopentenyl (prenyl) group at the N 6 position of adenine. This modified nucleotide finetunes the active site of RNA‐cleaving deoxyribozymes, resulting in a distinct shift of the cleavage site. DNA catalysts are reported to exclusively cut post‐transcriptionally modified RNAs. Abstract RNA‐cleaving deoxyribozymes can serve as selective sensors and catalysts to examine the modification state of RNA. However, site‐specific endonuclease deoxyribozymes...
Thu Aug 20, 2020 21:08
Photorelease of pyridines from their corresponding pyridinium ions in aqueous solution is difficult due to efficient photoinduced electron transfer (PET) from photoremovable protecting groups (PPGs) to the pyridinium. Driving the excited state of coumarin‐based PPG from S1 to T1 by introducing a heavy atom alleviates PET and enhances photolytic efficiency by hundreds‐fold. Abstract The photorelease of bioactive molecules has emerged as a valuable tool in biochemistry. Nevertheless, many...
Thu Aug 20, 2020 21:08
Described here is an efficient and broadly compatible early‐stage O‐sulfation approach based on sulfur(VI) fluoride exchange (SuFEx) chemistry. This strategy provides a powerful tool for the synthesis of O‐sulfate‐containing bioactive compounds. Abstract O‐sulfation is an important chemical code widely existing in bioactive molecules, but the scalable and facile synthesis of complex bioactive molecules carrying O‐sulfates remains challenging. Reported here is a general approach to O‐sulfation...
Thu Aug 20, 2020 21:05
An effective divergent synthesis of chiral spiroaminals and fused bicyclic acetals has been realized in up to 99 % yield with up to 99 % ee via an unusual enantioselective cyclopropanation‐rearrangement process. Abstract A highly enantioselective synthesis of various chiral heterobicyclic molecules including spiroaminals and fused bicyclic acetals has been developed via a chiral copper catalyzed cyclopropanation‐rearrangement (CP‐RA) approach under mild reaction conditions. Remarkably,...
Thu Aug 20, 2020 21:01
Copper‐catalyzed regioselective C−H alkenylation and borylative alkylation of quinoline N‐oxides with vinyl arenes in the presence of pinacol diborane has been developed. The reaction proceeds through the borylcupration of the vinyl arenes followed by nucleophilic attack of the resulting alkyl copper species to the quinoline N‐oxides. Benzoquinone and KO t Bu were necessary additives at the second step of the reaction. Abstract An efficient copper‐catalyzed regioselective C−H alkenylation...
Thu Aug 20, 2020 20:55
The formation of conjugated Breslow intermediates is a turnover‐limiting step in the NHC‐catalyzed γ‐butyrolactone formation via homoenolate addition. Structural and mechanistic studies including deuterium exchange experiments revealed that the formation of conjugated Breslow intermediates is facilitated by the proximity effects of pendant alkoxy groups on ortho‐N‐aryl groups of imidazolylidene catalyst. Abstract Hydrogen‐transfer in the tetrahedral intermediate generated from an imidazolylidene...
Thu Aug 20, 2020 20:54
The first atom‐economical stereoselective oxidative bioconjugation of carboxylic acid functionalities in amino acids and oligopeptides to aldehydes is demonstrated. It is also demonstrated that this stereoselective oxidative bioconjugation provides linker molecules with bioorthogonal handles for further functionalization by merging the oxidative coupling strategy with the click concept. Abstract The first stereoselective, near‐equimolar, and metal‐free oxidative bioconjugation of amino...
Thu Aug 20, 2020 20:54
Hindered secondary diarylamines Ar1NHAr2 can show chirality due to restricted rotation about their C−N bonds. Using a combination of dynamic analytical methods and computational models, we describe the requirements for atropisomerism in these diarylamines and provide a model for estimating their barrier to interconversion. Abstract In common with other hindered structures containing two aromatic rings linked by a short tether, diarylamines may exhibit atropisomerism (chirality due to restricted...
Thu Aug 20, 2020 20:53
Organic compounds are considered as promising electrode materials of aqueous zinc‐ion batteries (ZIBs) because of their resource renewability, environmental benignity and structural diversity. A comprehensive overview focusing on the energy storage mechanisms and research progress of Zn/organic batteries are discussed. Abstract Organic electroactive compounds are attractive to serve as the cathode materials of aqueous zinc‐ion batteries (ZIBs) because of their resource renewability, environmentally...
Thu Aug 20, 2020 20:53
In situ analytic techniques and theoretical calculations were employed to investigate the electroreduction of CO2 in metallic nanopores. It was found that the concave surface of metallic nanopores works like a pincer to capture and clamp CO2 and H2O precursors simultaneously, thus lowering the energy barriers of CO2 electroreduction. Abstract Metallic catalysts with nanopores are advantageous on improving both activity and selectivity, while the reason behind that remains unclear all along....
Thu Aug 20, 2020 20:53
The host–guest synergy of carbon dots in porous materials boosts an emerging class of functional composite materials with intriguing optical and electrical properties. This Minireview highlights the recent progress in this field, and gives insightful prospects for the future development of CDs@PM composite materials. Abstract Carbon dots (CDs) are emerging as a new class of carbon nanomaterials, which have inspired growing interest for their widespread applications in anti‐counterfeiting,...
Thu Aug 20, 2020 20:53
Nanoparticles with chaperone‐like activity may be considered as potential therapeutic agents to treat conformational diseases. This Minireview aims at emphasising the essential features required by nanomaterials to deal with toxic protein misfolding and accumulation. Abstract The generation of highly organized amyloid fibrils is associated with a wide range of conformational pathologies, including primarily neurodegenerative diseases. Such disorders are characterized by misfolded proteins...
Thu Aug 20, 2020 20:53
The hydrogenation of enynes with [(NHC)(cymene)RuCl2] (NHC=N‐heterocyclic carbene) complexes under UV irradiation leads to the formation of cyclic alkenes through the intervention of Grubbs‐type ruthenium complexes. This unorthodox entry into the realm of metathesis chemistry represents the first light‐driven catalyst system that is able to instigate alkyne gem‐hydrogenation with concomitant formation of a discrete metal carbene species. Abstract [(NHC)(cymene)RuCl2] (NHC=N‐heterocyclic...
Thu Aug 20, 2020 20:53
Nontoxic aryl germanes are shown to be of privileged stability under harsh fluorination conditions. They display superior reactivity and functional‐group tolerance in electrophilic iodinations and brominations, outcompeting silanes or boronic esters under rapid and additive‐free conditions. Abstract While halogenation is of key importance in synthesis and radioimaging, the currently available repertoire is largely designed to introduce a single halogen per molecule. This report makes the...
Thu Aug 20, 2020 20:52
A ligand‐regulated regiodivergent and stereoselective hydrosilylation of terpenes has been developed using earth‐abundant iron catalysts. Various silanes and terpenes were transformed with excellent selectivity into the corresponding allylic silanes and homoallylic silanes through 4,1‐ and 3,4‐addition, respectively. Abstract A method for the regiodivergent and stereoselective hydrosilylation of the basic industrial feedstock isoprene with unactivated silanes has been developed using earth‐abundant...
Thu Aug 20, 2020 20:48
A multiple‐color platinum complex (Pt2L) with super‐large Stokes shift was designed for super‐resolution imaging, showing an extremely low luminescence background and high photobleaching resistance. Moreover, upon light stimulation, a matter flux of Pt2L escaping from autolysosomes to the nucleus is detected, which represents a new transportation path. Abstract It is of great significance to track the platinum drugs in real time with super‐resolution to elucidate their mechanism of action,...
Thu Aug 20, 2020 20:48
With readily available oximes as five‐atom units, a variety of azepine and spiro‐tetrahydropyridine derivatives have been synthesized through the iminyl‐radical triggered 1,5‐hydrogen atom transfer/(5+2) or (5+1) annulation cascade protocol. This method exhibits broad substrate scope and good functional group compatibility. Abstract By integration of iminyl radical‐triggered 1,5‐hydrogen atom transfer and (5+2) or (5+1) annulation processes, a series of structurally novel and interesting...
Thu Aug 20, 2020 20:47
An efficient asymmetric electrosynthesis was developed with high yields and excellent enantioselectivities. This efficient process is mediated by a bifunctional squaramide catalyst, and it provides an innovative approach to asymmetric synthesis of highly valuable products bearing a fluorine‐containing stereocenter with excellent enantioselectivity (up to 95 % ee). Abstract An enantioselective bifunctional squaramide‐catalyzed detrifluoroacetylative alkylation reaction has been developed...
Thu Aug 20, 2020 20:45
A highly reversible Zn anode is achieved by using a phase‐separation electrolyte, where aqueous electrolyte is separated from Zn by a MOF‐confined thin layer hydrophobic Zn(TFSI)2‐TFEP organic electrolyte and a ZnF2‐Zn3(PO4)2 solid electrolyte interphase (SEI). The Zn anode achieves a high Coulombic efficiency of 99.9 % at 1 mA cm−2 for 350 cycles and stable Zn||MnO2 batteries. Abstract Aqueous Zn batteries are promising energy‐storage devices. However, their lifespan is limited by irreversible...
Thu Aug 20, 2020 20:45
Electrochemical control over the synthesis of nanoparticles of the metal–organic framework (MOF), HKUST‐1, is achieved using a nanopipette injection method to locally mix metal salt precursors and ligand reagents. The MOF nanocrystals are collected and characterised on a TEM grid. Single nanoparticle crystallisation is controlled and monitored in real time. Abstract Achieving control over the size distribution of metal–organic‐framework (MOF) nanoparticles is key to biomedical applications...
Thu Aug 20, 2020 20:43
Herein we describe the first organocatalytic asymmetric C(sp2)–H allylation of racemic trisubstituted allenoates with Morita–Baylis–Hillman (MBH) carbonates to access axially chiral tetrasubstituted allenoates. Various trisubstituted allenoates and MBH carbonates were well tolerated under mild reaction conditions, providing novel chiral tetrasubstituted allenoates with adjacent axial chirality and tertiary carbon stereocenters in high yields with good to excellent diastereoselectivities and enantioselectivities.
Thu Aug 20, 2020 18:50
High entropy alloy (HEA) nanoparticles hold great promise as tunable catalysts and surprisingly Pt‐Ir‐Pd‐Rh‐Ru nanoparticles can be synthesized under benign low‐temperature solvothermal conditions. Considering that alloy formation typically is difficult in oxygen rich environments, it is peculiar that five different metals can be simultaneously reduced and alloyed in a highly complex solvent reaction. Here in situ X‐ray scattering and transmission electron microscopy reveal the solvothermal formation...
Thu Aug 20, 2020 17:21
In this work, a record power conversion efficiency of 8.40% was obtained in single‐component organic solar cells (SCOSCs) based on double‐cable conjugated polymers. This is realized based on the finding that exciton separation plays the same important role as charge transport in SCOSCs. Herein, we designed two double‐cable conjugated polymers with almost the identical conjugated backbones and electron‐withdrawing side units, but the extra chlorine (Cl) atoms had different positions on the conjugated...
Thu Aug 20, 2020 15:06
We show the synthesis of a redox‐active quinone, 2‐methoxy‐1,4‐hydroquinone (MHQ), from a bio‐based feedstock and its suitability as electrolyte in aqueous redox flow batteries. We identified semiquinone intermediates at insufficiently low pH and quinoid radicals as responsible for decomposition of MHQ under electrochemical conditions. Both can be avoided and/or stabilized, respectively, using H 3 PO 4 electrolyte, allowing for reversible cycling in a redox flow battery for hundreds of cycles.
Thu Aug 20, 2020 14:11
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