Chiral self‐recognition and self‐discrimination are of vital importance to biological processes. In this work, 2D regular rhombic nanocrystals ( RS ‐NC ) were fabricated through heterochiral self‐discrimination between chiral polynuclear gold(I)‐sulfido complex enantiomers, [( R ‐BINAP) 4 Au 10 S 4 ]Cl 2 ( R ‐Au 10 ) and [( S ‐BINAP) 4 Au 10 S 4 ]Cl 2 ( S ‐Au 10 ), in MeOH without the need for any surfactants or templates. The monitoring of nanocrystals (NCs) formation...
Wed Jul 29, 2020 12:22
Inspired by the self‐assembly of nanoparticle superlattices, we report herein a general methodology that exploits long‐chain molecular ligands to induce ordered assembly of colloidal nanosheets (NSs), resulting in 2D laminate superlattices with high packing density. Co‐assembly of two types of NSs further enables 2D/2D heterostructured superlattices. As a proof of concept, co‐assembly of Ti 3 C 2 T x and graphene oxide (GO) NSs followed by thermal annealing leads to MXene‐rGO superlattices...
Wed Jul 29, 2020 11:01
Electrochemical side reactions, often referred to as “electrode fouling”, are known to be a major challenge in electro‐organic synthesis and the functionality of modern batteries. Often, polymerization of one or more components is observed. When reaching their limit of solubility, those polymers tend to adsorb on the electrode’s surface, resulting in a passivation of the respective electrode area, which may impact electrochemical performance. Here, matrix‐assisted laser desorption/ionization‐mass...
Tue Jul 28, 2020 22:00
Stereoselective and temporally controlled supramolecular polymerizations are ubiquitous in nature and is a desirable attribute to the design of chiral, well‐defined functional materials. Kinetically controlled, living supramolecular polymerization (LSP) has emerged recently to synthesize supramolecular polymers with controlled length and narrow dispersity. On the other hand, stringent design requirements for chiral discriminating monomers precludes the stereoselective control of the supramolecular...
Tue Jul 28, 2020 21:58
Radiolabelling is fundamental in drug discovery and development as it is mandatory for preclinical absorption, distribution, metabolism and excretion (ADME) studies and late‐stage human clinical trials. Herein, a general, effective and easy to implement method for the multiple site incorporation of deuterium and tritium atoms using the commercially available and air‐stable iridium precatalyst [Ir(COD)(OMe)] 2 is described. A large scope of pharmaceutically relevant substructures can be labelled...
Tue Jul 28, 2020 20:45
The reactivity of the electron‐rich anionic Al(I) (‘aluminyl’) compound K 2 [(NON)Al] 2 (NON = 4,5‐bis(2,6‐diisopropylanilido)‐2,7‐di‐ tert ‐butyl‐9,9‐dimethylxanthene) towards mono‐ and disubstituted arenes is reported. C‐H activation chemistry with n ‐butylbenzene gives exclusively the product of activation at the arene meta position. Mechanistically, this transformation proceeds in a single step via a concerted Meisenheimer‐type transition state. Selectivity is therefore based on similar...
Tue Jul 28, 2020 20:40
Microdroplet chemistry is attracting increasing attention for accelerated reactions at the air/solution interface. We report here a novel voltage‐controlled interfacial microreactor allowing acceleration of electrochemical reactions which are not observed in bulk or conventional electrochemical cells. The microreactor is formed at the interface of the Taylor cone in an electrospray emitter with a large orifice. This allows continuous contact of the electrode and the reactants at/near the interface....
Tue Jul 28, 2020 20:25
Multi‐functionalization and isomer‐purity of fullerenes are crucial tasks for the development of fullerene chemistry in various fields. In both current main approaches – tether‐directed covalent functionalization and supramolecular masks – the control of regioselectivity requires multi‐step synthetic procedures to prepare the desired tether or mask. Herein, we describe light‐responsive tethers, containing an azobenzene photoswitch and two malonate groups, in the double cyclopropanation of [60]fullerene....
Tue Jul 28, 2020 20:02
All‐solid‐state lithium ion batteries (LIBs) have been recognized as one of the ideal choices for energy storage techniques for practical applications given their safety and long‐term stability. However, limited availability of electrode active materials with high capacity and long‐term stability fabricated through low cost procedure remains a bottleneck. Herein, we report a truxenone‐based covalent organic framework (COF‐TRO) as cathode materials for all‐solid‐state LIBs. The high‐density carbonyl...
Tue Jul 28, 2020 19:00
It is of great value to detect the biological molecules in live cells. However, probes for imaging low abundance targets in live cells are limited by the “one‐to‐one” signal‐triggered model. Here, we introduce the concept of amplified FRET nanoflare, which employs high abundance endogenous mRNA as fuel strands to amplify the detection of low abundance intracellular miRNA. As far as we know, this is the first report of an endogenous mRNA‐powered nanomachine for intracellular molecular detection. We...
Tue Jul 28, 2020 18:24
We report in this communication the dramatic impact of the addition of N ‐heterocyclic carbene (NHC) ligands on the reactivity and selectivity of heterogeneous Ru catalysts in the context of C‐H activation reactions. Using a simple and robust protocol, we have prepared a series of new air stable catalysts starting from commercially available Ru on carbon (Ru/C) and differently substituted NHCs. Associated with C‐H deuteration processes, depending on Ru/C‐NHC ratios, the chemical outcome can be controlled...
Tue Jul 28, 2020 17:25
A series of largely π ‐extended multichromophoric molecules including cross‐conjugated, half cross‐conjugated, conjugation‐interrupted and linearly conjugated systems were synthesized and characterized. These multichromophoric molecular systems revealed interesting structural‐property relationships. While the cross‐conjugated bisporphyrin‐fused pentacenequinone chromophores displayed broad UV‐Vis absorption bands spanning from 350 nm through 650 nm, the linearly‐conjugated bisporphyrin‐fused pentacene...
Tue Jul 28, 2020 17:02
Intracellular construction of artificial organelle‐like architectures is an emerging paradigm for recreating cellular functions and interfering disease process. Design of controllable dynamic systems is vital for the construction of organelle‐like architectures in living cells, but has proven to be remarkably difficult due to the lack of control over defined topology and topological transformation of self‐assembled structures. Herein, we report a DNA based dynamic assembly system that achieves lysosomal...
Tue Jul 28, 2020 17:01
Currently CRISPR‐Cas9 is a widely used efficient tool for gene editing. Precise control over CRISPR‐Cas9 system in temporal and spatial resolution is essentially important for studying gene regulation and editing. Here, we presented a novel light‐controlled crRNA via coupling vitamin E and a photolabile linker at 5’ terminus to inactivate CRISPR‐Cas9 system. The vitamin E modification did not affect ribonucleoprotein (RNP) formation of Cas9/crRNA /tracrRNA complexes, but did inhibit the association...
Tue Jul 28, 2020 16:59
An organocatalytic enantioconvergent synthesis of chiral tetrasubstituted allenes by remote asymmetric 1,8‐addition of an in situ generated indole imine methide is disclosed. With suitable chiral phosphoric acid catalysts, a range of racemic indole‐substituted propargylic alcohols reacted smoothly with nucleophiles to provide mild and efficient access to enantioenriched allenes with high enantioselectivities. Abstract An organocatalytic enantioconvergent synthesis of chiral tetrasubstituted...
Tue Jul 28, 2020 16:12
Getting bistable under pressure : The paramagnetic cyanido FeIIICoII complex is converted into a magnetic molecular switch upon application of a moderate pressure. The higher the pressure, the broader the hysteresis. Thus, when an adequate pressure is applied, the bistability domain corresponding to the full dia‐/paramagnetic conversion can be adjusted to reach room temperature. Abstract A key challenge in the design of magnetic molecular switches is to obtain bistability at room temperature....
Tue Jul 28, 2020 16:11
Shape shifting : Reported here is a novel, alternating copolymer vesicle that exhibits drastic and complex multimode shape oscillations in real time, including swelling/deswelling, twisting/detwisting, stretching/shrinking, fusion/fission, and multiple division. The oscillations are controlled by the polymer concentration and driven by the Belousov–Zhabotinsky (B‐Z) oscillatory reaction. This vesicle is a promising model system for mimicking cellular oscillatory behaviors. Abstract Engineering...
Tue Jul 28, 2020 16:07
Copper‐catalyzed borylative multicomponent couplings, involving olefins and C−N electrophiles, constitute an efficient approach to high‐value amine and nitrile products. This Minireview assesses the progress in this rapidly emerging field and surveys the borylative union of allenes, dienes, styrenes, and related olefins, with imines, nitriles, and related electrophiles. Abstract Copper‐catalyzed borylative multicomponent reactions (MCRs) involving olefins and C−N electrophiles are a powerful...
Tue Jul 28, 2020 16:06
Silicate ECNU‐36 nanosheets with 17 nm thickness have been hydrothermally synthesized using 1,5‐bis(tetramethylimidazolium) hydroxide as OSDA and solid‐state NH4F as additive. ECNU‐36 is a quasi‐pure beta polymorphs CH (95 %) with a minor intergrown phase of polymorph B (5 %). The highly pure crystal phase with fewer faults endows ECNU‐36 with promising adsorption performance for olatile organic compounds (VOCs). Abstract A quasi‐pure CH polymorph of microporous zeolite beta, named ECNU‐36,...
Tue Jul 28, 2020 16:04
A metal‐free C‐H allylation strategy is described to access diverse functionalized ortho ‐allyl‐iodoarenes. The method employs hypervalent (diacetoxy)iodoarenes and proceeds through the iodane‐guided “iodonio‐Claisen” allyl transfer. The use of allylsilanes bearing electron‐withdrawing functional groups unlocks the functionalization of a broad range of substrates, including electron‐neutral and electron‐poor rings. The resulting ortho ‐allylated iodoarenes are versatile building blocks, with...
Tue Jul 28, 2020 15:32
The nonradiative recombination of electrons and holes has been identified as the main cause of energy loss in hybrid organic‐inorganic perovskite solar cells (PSCs). Sufficient build‐in field and defect passivation can facilitate effective separation of electron‐hole pairs to address the crucial issues. Here, we for the first time introduce a homochiral molecular ferroelectric into the PSCs to enlarge the build‐in field of perovskite films, facilitating more effective charge separation and transporting....
Tue Jul 28, 2020 15:32
Single‐atom catalysts (SACs) are of great interest due to their ultrahigh activity and selectivity. However, the lack of general synthetic protocol makes it difficult in the construction of model SACs to discern activity difference of diverse single‐atom metal species. Herein, a universal synthetic strategy towards single‐atom metal implanted N‐doped carbon (M1‐N‐C; M = Fe, Co, Ni and Cu) has been developed based on multivariate MOFs. The M1‐N‐C catalysts, featuring identical parameters in chemical...
Tue Jul 28, 2020 15:30
Due to the synergistic “push‐pull” effect of vicinal electron‐donating and electron‐withdrawing groups, donor−acceptor (D‐A) cyclopropanes have been recognized as one of the most powerful reagents to generate polyfunctional reactive intermediates after a strain‐driven ring cleavage. Enantioselective reactions of D‐A cyclopropanes provide an efficient approach to enantioenriched acyclic and cyclic compouds. A number of chiral Lewis/Brønsted acids, transition metals and organocatalysts have been designed...
Tue Jul 28, 2020 14:24
Golden ratio : Four‐dimensional gold (Au) nanostructures were fabricated by a dissipative assembly strategy. The dissipative character of the system was realized by utilizing deoxyribonucleic acid (DNA) as the fuel and exonuclease III (Exo III) as the energy‐dissipating unit, to generate AuNPs functionalized with short single‐stranded DNA oligonucleotides. The assemblies possess surface plasmonic resonance properties. Abstract Organization of gold nanoobjects by oligonucleotides has resulted...
Tue Jul 28, 2020 13:52
Vacancy‐rich Ni(OH)2 nanosheets are proposed to realize a direct one‐step route for the electrooxidation of amino C−N bonds to nitrile C≡N bonds for nitrile production. During the catalytic reaction the local vacancy‐induced electropositive site chemisorbs the N atom with a lone pair of electrons and then attacks the corresponding N−H bond. Abstract Electrochemical synthesis based on electrons as reagents provides a broad prospect for commodity chemical manufacturing. A direct one‐step...
Tue Jul 28, 2020 13:50
Ultrafast exciton self‐trapping and delocalization in cycloparaphenylenes was investigated by femtosecond broadband fluorescence upconversion technique. By accessing one‐photon and two‐photon allowed states, ultrafast torsional reorganizations and exciton self‐trapping via electron‐vibrational coupling were studied comparatively. Abstract Upon photon absorption, π‐conjugated organics are apt to undergo ultrafast structural reorganization via electron‐vibrational coupling during non‐adiabatic...
Tue Jul 28, 2020 13:50
Fusion between two different emulsion communities is demonstrated. The modulation of fusion frequency, fusion‐induced structural evolution with the formation of Janus or diversified patchy morphologies, as well as enzyme‐catalytic reaction‐mediated membrane maturation and controlled motility, are highlighted. Abstract The biomimetic dynamic behaviours of emulsions are receiving increasing attention from the broad scientific community; however, the spatiotemporal control and functionalization...
Tue Jul 28, 2020 13:49
Carboxylate, activate ! Pd catalysis is generally assumed to be ineffective for cross‐coupling with most oxygen‐based electrophiles. It is demonstrated not only that alkenyl carboxylates are able couple with boronic acids under extremely mild conditions, but that there are two distinct pathways for C−O activation. The result is an operationally simple arylation of many pharmaceutically relevant (hetero)cyclic cores with excellent functional‐group tolerance. Abstract Carboxylate esters have...
Tue Jul 28, 2020 13:49
Branches through the window : Black‐body absorption is achieved with Au nanorods by versatile control of their surface structures, namely the number and shape of the emerging Au domains. The branched structures show excellent photothermal and photoacoustic properties in the second NIR window. Abstract The localized surface plasmon resonance (LSPR) of plasmonic nanomaterials is highly dependent on their structures. Going beyond simple shape and size, further structural diversification demands...
Tue Jul 28, 2020 13:47
Simple self‐assembly methods cannot be used to attain high‐level organizations such as those found in biological systems. The introduction of non‐equilibrium processes and harmonization of multiple actions is required. As a novel methodology beyond self‐assembly, nanoarchitectonics, whose main conceptual aim is the formation of functional materials from nanoscopic units through the fusion of different scientific disciplines, has been proposed for the creation of bio‐like high functionality hierarchically...
Tue Jul 28, 2020 13:47
One way or another : The coexistence of two isoenergetic electromers of the novel BeOBeC molecule, possessing practically indistinguishable IR features, has been revealed by quantum‐chemical calculations. Further, the triplet state of a so far unknown C 2v ‐symmetric rhombus‐like four‐membered ring 3[Be(O)(C)Be] is predicted to represent the global minimum on the potential‐energy surface in the thermal reaction of Be2 with CO. Abstract Extensive high‐level quantum‐chemical calculations...
Tue Jul 28, 2020 13:45
Face on : The all‐octahedral symmetric nesting Ag cluster, that is, [Ag100(SC6H3 3,4F2)48(PPh3)8]−, is reported. The structural model is informed by a deep understanding of the nucleation and evolution principles for FCC‐based Ag nanoclusters, but is radically different from previous models, and is unprecedented in the context of Ag clusters. FCC=face centered cubic. Abstract Precise atomic structure of metal nanoclusters (NCs) is fundamental for elucidating the structure–property relationships...
Tue Jul 28, 2020 13:43
The present work demonstrates a CuCl and anionic chiral cobalt(III)‐catalyzed enantioselective ring‐opening reaction. The small size, “ligand‐free” copper species enabled the cross‐coupling of iodonium salts with a series of bulky aromatic amines in high ee values. The chiral cobalt(III) anion causes appreciable chemical shift changes of cyclic diaryliodoniums in 1 H NMR spectra.
Tue Jul 28, 2020 13:00
Integration of multiple agent therapy (MAT) into one probe has been considered as a promising approach to improve therapeutic efficiency for cancer treatment. However, MAT probe, if entering the cell as a whole, might not be optimal for each individual therapeutic agent (with different physicochemical properties), to achieve their best performance, which hinders the strategy optimization. Here, we report a peptide‐conjugated‐AIEgen (FC‐PyTPA): upon loading with siRNA, it can be self‐assembled into...
Tue Jul 28, 2020 12:59
A sunlight‐powered process is reported that employs carbon dots (CDs) as light absorber for the conversion of lignocellulose into sustainable H 2 fuel and organics. This photocatalytic system operates in pure and untreated sea water using a benign pH (2‐8) at ambient temperature and pressure. The CDs can be produced in a scalable synthesis directly from biomass itself and their solubility allows for good interactions with the insoluble biomass substrates. They also display excellent photophysical...
Tue Jul 28, 2020 12:54
We present a strategy to achieve highly cooperative photoswitching, where the initial switching event greatly facilitates subsequent switching of the neighboring unit. By linking donor/acceptor substituted dihydropyrenes via suitable p‐conjugated bridges, the quantum yield for the second photochemical ring‐opening process could be enhanced by more than two orders of magnitude as compared to the first ring‐opening. As a result, the intermediate mixed switching state is not detected during photoisomerization...
Tue Jul 28, 2020 12:24
Both experimental and theoretical investigations have revealed that the chemical and physical properties of graphene are crucially determined by their topological structures. Therefore, the atomically precise synthesis of graphene nanostructures is essential for studying their fundamental physiochemical properties as well as their introduction in promising applications. Among the large family of graphene nanostructures, those containing rich or fully zigzag‐edged structures exhibit unique electronic,...
Mon Jul 27, 2020 22:00
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