Less is more : Toehold‐mediated strand displacement has been used to produce dynamic DNA nanostructures and networks; however, the complexity of sequence design dramatically increases as the size and complexity of the DNA network increases. Fuzzy strand displacement allows a single input strand to displace multiple substrate strands and multiple input strands to displace a single substrate strand, reducing the complexity of DNA‐sequence design. Abstract Toehold‐mediated DNA strand displacement...
Mon Jun 22, 2020 22:48
Robust COFs for separation : A general strategy for developing 3D chemically stable covalent organic frameworks through hydrophobic engineering is presented. The application of 3D COF materials for oil/water separation over a wide pH range is explored. Abstract The development of three‐dimensional (3D) covalent organic frameworks (COFs) with high chemical stability is of critical importance for their practical use. In this work, it is demonstrated that the stability of 3D COFs can be improved...
Mon Jun 22, 2020 22:47
A new, universal 19F broadband relaxation‐edited NMR experiment enables fast screening of the entire drug‐relevant fluorine chemical shift range for distinct hit molecules in a single measurement. It further facilitates the efficient generation and evaluation of large, chemically diverse compound libraries and expedites the ligandability assessment of any macromolecular target. Abstract Fragment‐based lead discovery has become a fundamental approach to identify ligands that efficiently...
Mon Jun 22, 2020 22:47
The mechanism of aggregation‐induced emission is revealed by monitoring real time structural evolution and dynamics of the electronic excited state. The formation of Woodward–Hoffmann cyclic intermediates as nonradiative relaxation pathway is observed in dilute solutions of tetraphenylethylene upon ultraviolet excitation. In solid state, the electronic excitation is preserved, and the molecule fluoresces efficiently. Abstract The mechanism of aggregation‐induced emission, which overcomes...
Mon Jun 22, 2020 22:47
Methyltransferase enzymes (MTs) selectively deliver methyl substituents to an array of molecules, thereby controlling gene expression or modulating the bioactivity of therapeutically important natural products. A MT was engineered for selective carboxy(m)ethylation to give an orthogonal MT that was combined with the SAM‐derivatising enzyme CmoA to create new carboxymethylation pathways. Abstract S ‐adenosyl‐l ‐methionine (SAM)‐dependent methyltransferases (MTs) catalyse the methylation...
Mon Jun 22, 2020 22:46
The hypervalent iodine reagent PIDA in combination with a nucleophilic amine (DABCO or pyridine) induces α‐functionalization of enones with three different nucleophiles. The reaction is proposed to proceed through the umpolung of Morita–Baylis–Hillman type intermediates. The proposed mechanism is supported by spectroscopic studies that details the conversion of several reaction intermediates into products. Abstract Herein we report on the umpolung of Morita–Baylis–Hillman type intermediates...
Mon Jun 22, 2020 22:43
A photoelectrochemical reactor comprised of a III‐V‐based photovoltaic cell integrated with nickel foil as an O2 evolving catalyst achieves a solar‐to‐hydrogen (STH) efficiency of 18.3 % at low light concentration without optical lenses. An STH efficiency of 13 % is attained at high light concentration with optical lenses. A 100 hour test at 100–200 suns showed no degradation or deviation from product stoichiometry (H2/O2=2). Abstract The major challenge in solar water splitting to H2...
Mon Jun 22, 2020 22:43
Process intensification through continuous flow reactions has increased the production rates of fine chemicals and pharmaceuticals. Catalytic reactions are accelerated through an unconventional and unprecedented use of a high‐performance liquid/liquid counter current chromatography system. Product generation is significantly faster than in traditional batch reactors or in segmented flow systems, which is exemplified through stereoselective phase‐transfer catalyzed reactions. This methodology also...
Mon Jun 22, 2020 22:00
Artificial nanorobots that can recognize molecular triggers and respond with programable operations provide an inspiring proof‐of‐principle for personalized theragnostic applications. Herein, we construct an intelligent DNA nanorobot for autonomous blood anticoagulation in human plasma. The DNA nanorobot comprises a barrel‐shaped DNA nanostructure as the framework and molecular reaction cascades embedded as the computing core. This nanorobot can intelligently sense the concentration of thrombin in...
Mon Jun 22, 2020 19:09
Understanding the biomolecular interactions in a specific organelle has been a long‐standing challenge because it requires super‐resolution imaging to resolve the spatial locations and dynamic interactions of multiple biomacromolecules. Two key difficulties, however, are that molecular probes suitable for super‐resolution nanoscopy are rather rare, and more adversely the use of multiple probes complicates their cellular uptakes, biodistributions, and spectral distinctions. Here, we report a quinolinium...
Mon Jun 22, 2020 18:27
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 monomeric protein that forms a bright far‐red fluorescent assembly with (4‐hydroxy‐3‐methoxy‐phenyl)allylidene rhodanine (HPAR‐3OM). As HPAR‐3OM is essentially non‐ fluorescent in solution and in cells, frFAST can be imaged with high contrast in presence of free HPAR‐3OM, which...
Mon Jun 22, 2020 18:11
Zeolite‐catalyzed alkene cracking is key to optimize the size of hydrocarbons. The nature and stability of intermediates and transition states (TS) are, however, still debated. Herein, transition path sampling and blue moon ensemble density functional theory simulations are combined to unravel the behavior of C7 alkenes in CHA zeolite. Free energy profiles are determined, linking π‐complexes, alkoxides and carbenium ions, for B1 (secondary to tertiary) and B2 (tertiary to secondary) β‐scissions....
Mon Jun 22, 2020 18:09
Extensive high‐level quantum chemical calculations reveal that the rod‐shaped molecule BeOBeC, which was recently generated in matrix experiments, features two nearly isoenergetic 5Σ quintet (56) and 3Σ triplet (36) states. Their IR features are hardly distinguishable at finite temperature. The major difference concerns the mode of spin coupling between the terminal beryllium and carbon atoms. Further, the ground‐state potential‐energy surface of the [2Be,C,O] system at 4K is presented and differences...
Mon Jun 22, 2020 17:49
Understanding the thermal aggregation behaviors of metal atoms is of significant importance for precise synthesis of supported metal clusters. Here, derived from a metal‐organic framework encapsulating a trinuclear Fe III 2 Fe II complex (denoted as Fe 3 ) within the channels, a well‐defined nitrogen‐doped carbon layer is fabricated as an ideal support for stabilizing the generated iron nanoclusters. Atomic replacements of the Fe II by other metal(II) ions (e.g., Zn II /Co II ) via synthesizing...
Mon Jun 22, 2020 17:48
Developing high capacity and stable cathodes is a key to successful commercialization of aqueous Zn‐ion batteries (ZIBs). Pure layered V 2 O 5 has a high theoretical capacity (585 mAh/g), but it suffers severe capacity decay. Pre‐inserting cations into V 2 O 5 can substantially stabilize the performance, but at an expense of lowered capacity. Here we show that an atomic layer deposition derived V 2 O 5 can be an excellent ZIB cathode with high capacity and exceptional cycle stability...
Mon Jun 22, 2020 17:47
In recent years, boron‐containing materials and in particular boron nitride, have been identified as highly selective catalysts for the oxidative dehydrogenation of alkanes such as propane. Until now, no mechanism exists that can explain both the unprecedented selectivity, the observed surface oxyfunctionalization, as well as the peculiar kinetic features of the reaction. In this contribution we combine catalytic activity measurements with quantum chemical calculations to put forward a bold new...
Mon Jun 22, 2020 16:45
A key challenge in the design of magnetic molecular switches is to obtain bistability at room temperature. Here, we show that a moderate pressure allows converting a paramagnetic Fe III 2 Co II 2 square complex into a molecular switch exhibiting a full dia‐ to para‐magnetic transition: Fe II Co III ⬄ Fe III Co II . Moreover, the complex follows a rare behavior: the higher the pressure is, the broader the magnetic hysteresis is. Thus, the application of an adequate pressure allows inducing...
Mon Jun 22, 2020 16:10
Trivalent aluminium compounds are well known for their reactivity as Lewis acids/electrophiles, a feature that is exploited in many pharmaceutical, industrial and laboratory‐based reactions. Recently, a series of isolable aluminium(I) anions ('aluminyls') have been reported, which offer an alternative to this textbook description: these reagents behave as aluminium nucleophiles. This minireview covers the synthesis, structure and reactivity of aluminyl species reported to date, together with their...
Mon Jun 22, 2020 14:08
The preparation of multihelicenic systems by conventional organic synthesis is a challenging task and under continuous development. In parallel, using complexing units grafted to or incorporated within the helicene core and taking advantage of coordination/organometallic chemistry constitutes a powerful strategy to obtain multihelicenic structures. This minireview focuses on the state‐of‐the‐art preparation of metal‐based multihelicenic architectures such as coordination‐driven supramolecular assemblies...
Mon Jun 22, 2020 14:07
An enantioselective 1,4‐addition of α,β ‐unsaturated carboxylic acids with cyc loalkano nes is developed using chiral amine–boronic acid cooperative catalysts. In the presence of chiral amine and boronic acid, cycloalkanones and carboxylic acids are activated as chiral enamines and mixed anhydrides, respectively. The corresponding 1,4‐adducts are obtained in high yield with high enantioselectivity. Furthermore, subsequent oxylactonization of the 1,4‐adducts gives spirolactones with high disastereoselectivity.
Mon Jun 22, 2020 12:51
Proteins are an endless source of inspiration. By carefully tuning the amino‐acid sequence of proteins, nature made them evolve from primary to quaternary structures, a property specific to protein oligomers and often crucial to accomplish their function. On the other hand, the synthetic macrocycles cucurbiturils (CBs) have shown outstanding recognition properties in water, and a growing number of (host) n :(guest) n supramolecular polymers involving CBs have been reported. However, the burgeoning...
Mon Jun 22, 2020 12:50
A single‐molecule memory element is electrically‐controlled using two distinct reaction mechanisms as reported by K. Moth‐Poulsen, J. Hihath, and co‐workers (DOI: https://doi.org/10.1002/anie.20200230010.1002/anie.202002300). By using separate electrically‐controllable reactions for the forward and reverse reactions the bistable norbornadiene–quadricyclane system can be set in either state. The device can be switched through multiple cycles when a square‐wave voltage signal is applied to the molecule....
Mon Jun 22, 2020 11:36
Puzzling over a diradical: Piecing together the “correct” combination of an azaacene, phenoxyl groups and dithienobenzene regiosiomers is rewarded by obtaining quinoidal azaacenes with almost pure diradical character stable for weeks in the solid state and persistent in solution. For more information see the Communication by J. Freudenberg, U. H. F. Bunz et al. (DOI: https://doi.org/10.1002/anie.20191597710.1002/anie.201915977).
Mon Jun 22, 2020 11:36
Pillar[n ]MaxQ were designed and synthesized by L. Isaacs and co‐workers in their Research Article (DOI: https://doi.org/10.1002/anie.20200590210.1002/anie.202005902). Pillar[n ]MaxQ display extreme affinity toward hydrophobic (bis)quaternary ammonium ions in water which renders them prime candidates for a variety of sequestration applications.
Mon Jun 22, 2020 11:32
Escaping from the planar geometry of trivalent boron Lewis acids is possible by incorporating a boron atom at the edge of the triptycene scaffold. In their Communication (DOI: https://doi.org/10.1002/anie.20200311910.1002/anie.202003119), G. Berionni and co‐workers describe the preparation of the elusive 9‐boratriptycene, a triarylborane with unprecedented structure and high Lewis acidity, due to the very low reorganization energy of the triptycene core and the absence of conjugation of its B atom...
Mon Jun 22, 2020 11:31
The “magical” combination of the PIP auxiliary and 3,3′‐substituted BINOL ligands enables the highly asymmetric functionalization of unbiased methylene C(sp3)−H bonds. As B.‐F. Shi et al. show in their Communication (DOI: https://doi.org/10.1002/anie.20200450410.1002/anie.202004504), a range of chiral γ‐lactams were prepared via enantioselective methylene C−H alkenylation/aza‐Wacker cyclization.
Mon Jun 22, 2020 11:29
Ultracold, isolated lipids in the gas phase adopt specific conformations anchored by intramolecular interactions. In their Communication (DOI: https://doi.org/10.1002/anie.20200245910.1002/anie.202002459), C. Arenz, K. Pagel and co‐workers show that cryogenic infrared spectroscopy combined with quantum chemical calculations can reveal the three‐dimensional structure of lipids in the gas phase and allow to distinguish double‐bond isomers.
Mon Jun 22, 2020 11:22
Just like a horse capturing a pawn to win the position at a chess game, nitrogen‐centered radical selectivity for hydrogen atom abstraction allows for a novel directed aliphatic C−H fluorination methodology. As described by D. Bafaluy, Z. Georgieva, and K. Muñiz in their Communication (DOI: https://doi.org/10.1002/anie.20200490210.1002/anie.202004902), the unique and outstanding performance of halogen catalysis enables the use of simple fluoride as fluorine source in a homogeneous approach to 1,3‐...
Mon Jun 22, 2020 11:22
Surfactant‐directed functionalization is a promising tool for enabling targeted modification of two‐dimensional nanomaterials and open up a whole new spectrum of exciting chemistry to be explored. As demonstrated by C. Backes et al. in their Research Article (DOI: https://doi.org/10.1002/anie.20200573010.1002/anie.202005730), investigation of the heterogenous reaction of chloroauric acid at the nanosheet–solution interface reveals that the surfactant plays a significant role in governing the reactivity...
Mon Jun 22, 2020 11:21
Perfluorinated compounds have found wide applications but have adverse effects on health and environment. There is a need to selectively recover them from process and surface waters. In their Communication (DOI: https://doi.org/10.1002/anie.20200295310.1002/anie.202002953), D. E. De Vos et al. show that a microporous zeolite Beta, in its all‐silica form, shows outstanding capacity and affinity for the uptake of PFCs like perfluorooctanoic acid and perfluorooctanesulfonic acid, even in the presence...
Mon Jun 22, 2020 11:21
C−H bond activation of the Jahn–Teller distorted adamantane cation by a single H2O molecule is probed by IR spectroscopy and DFT calculations in the Research Article by O. Dopfer et al. (DOI: https://doi.org/10.1002/anie.20200363710.1002/anie.202003637). The results provide a quantitative molecular level understanding of the initial activation by a single polar solvent molecule in the radical cation mechanism for functionalization of diamondoids. A drastic C−H stretch frequency shift along with...
Mon Jun 22, 2020 11:21
The ultrafast transformation of a bulk metal–organic framework (MOF) into ultrathin metal oxyhydroxide nanosheets for oxygen evolution reaction (OER) through electric‐field hydrolysis is demonstrated by L. Zhang, Q. Chen, M. Hong et al. in their Research Article (DOI: https://doi.org/10.1002/anie.20200442010.1002/anie.202004420). The as‐prepared nanosheets exhibit excellent OER performance, and the evolution process from bulk MOF to metal oxyhydroxide nanosheets is investigated in detail.
Mon Jun 22, 2020 11:21
Rational nanostructure engineering of electrode materials is an efficient approach to improve their electrochemical performance. In their Research Article (DOI: https://doi.org/10.1002/anie.20200419310.1002/anie.202004193), L. Zhang and co‐workers combined structural design and in situ TEM characterization to unveil the advances of nanostructure design of alloy‐type anodes, thereby realizing electrode materials with highly improved performance in potassium‐ion batteries.
Mon Jun 22, 2020 11:20
3D ordered mesoporous (3DOM) materials used for electrochemical CO2‐to‐CO conversion offer potential ways to close the carbon loop and harvest renewable energies. In the Research Article (DOI: https://doi.org/10.1002/anie.20200414910.1002/anie.202004149), Z. Bai, Z. Chen, and co‐workers show a trade‐off between active‐site exposure with structural stability and reveal an electron density reconfiguration at the Sn–Ti–O interface. The optimal nanostructured catalyst improves the half‐cell energy...
Mon Jun 22, 2020 11:14
A molecularly engineered lithium—arene complex (LAC) with a sufficiently low redox potential enables the incorporation of active Li in Si‐based anodes to generate ideal Li contents in a full cell. In their Research Article (DOI: https://doi.org/10.1002/anie.20200241110.1002/anie.202002411), J. Hong, M. Lee et al. demonstrate how a precise control of the prelithiation degree and of the spatial distribution of active Li in the electrodes is achieved by using the tailored LAC solution.
Mon Jun 22, 2020 11:09
Cycles and chains : The first perfluorinated auracycles and complexes containing Au(CF2) n Au chains are prepared. LAu(CF2)4AuL complexes adopt folded conformations stabilized by an aurophilic interaction depending on the auxiliary ligand L. The study of their dynamic behaviour in solution has allowed the energy associated with an aurophilic interaction to be determined. Abstract The first binuclear AuI compounds containing bridging (CF2) n chains (n =4, 6, 8) and AuIII metallaperfluorocyclopentanes...
Mon Jun 22, 2020 11:02
Water‐in‐salt electrolytes have received particular attention for their electrochemical stability properties. It is now shown that water reduction is always present from the first measured currents, and that associated with this water reduction, LiTFSI precipitation occurs. Abstract Water‐in‐salt electrolytes based on highly concentrated bis(trifluoromethyl)sulfonimide (TFSI) promise aqueous electrolytes with stabilities nearing 3 V. However, especially with an electrode approaching the...
Mon Jun 22, 2020 11:01
Chain walking makes the difference : The utilization of chain‐walking features can enable new polymerization strategies (gas‐phase polymerization and heterogenized slurry‐phase polymerization) using existing late‐transition‐metal‐based olefin polymerization catalysts. Abstract The polyolefin industry is dominated by gas‐phase and slurry‐phase polymerization using heterogeneous catalysts. In contrast, academic research is focused on homogeneous systems, especially for late‐transition‐metal...
Mon Jun 22, 2020 11:01
No need to be sour : CO2/CH4 and H2S/CH4 separation performance of glassy polyimide membranes can be tailored by finely tuning the DAM:DABA ratio in the 6FDA‐DAM:DABA polyimide backbone. This facile tunability is attractive for their applications for challenging sour gas separation (that is, methane contaminated with undesirable acid gases (CO2 and H2S)) across a spectrum of feed compositions. Abstract Glassy polyimide membranes are attractive for industrial applications in sour natural...
Mon Jun 22, 2020 11:01
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