Plateau–Rayleigh (P‐R) instability occurring on Brownian colloidal particles was observed and used for the surface patterning of colloidal rings. Multi‐patch rings, one‐patch rings, and patchy disks were synthesized in high yields. The number and size of patches are tunable, and the patches were functionalized to prepare pH‐responsive inverse patchy colloids. Abstract Plateau–Rayleigh (P‐R) instability occurring on Brownian colloidal particles is presented. This instability can be used for...
Fri Oct 11, 2019 18:41
Fe Maiden: An [Fe34] molecular metal oxide consists of an [Fe4] tetrahedron encapsulated in a [Fe18] truncated tetrahedron, face‐capped by four [Fe3] triangles, and is characterised by alternate layers of tetrahedral and octahedral Fe ions linked by oxide and hydroxide anions. Abstract The dissolution of anhydrous iron bromide in a mixture of pyridine and acetonitrile, in the presence of an organic amine, results in the formation of an [Fe34] metal oxide molecule, structurally characterised...
Fri Oct 11, 2019 18:41
Coordination isomerism can be exploited to control supramolecular assembly processes, as reported by G. Fernández and co‐workers in their Communication (DOI: https://doi.org/10.1002/anie.20190800210.1002/anie.201908002). Tuning the coordination isomerism of a PtII complex enables reversible switching between two distinct aggregate species (1D fibers↔2D lamellae) with different photoresponsive behavior. This approach could be used to create novel stimuli‐responsive materials and achieve size control...
Fri Oct 11, 2019 18:41
Pyramid power: Owing to the drastic pyramidalization around their trivalent boron atom and to the presence of a cationic phosphonium back‐side bridge, the Lewis acidity of the cage‐shaped 9‐bora‐10‐phosphonium triptycenes surpasses that of all trivalent boron Lewis acids generated to date. Abstract Bending the planar trigonal boron center of triphenylborane by connecting its aryl rings with carbon or phosphorus linkers gave access to a series of 9‐boratriptycene derivatives with unprecedented...
Fri Oct 11, 2019 18:41
The lattice‐oxygen‐involved UOR mechanism on Ni4+ active sites has significantly faster reaction kinetics than the conventional UOR mechanism occurred on Ni3+ active sites. The resultant Ni4+ catalyst on a glassy carbon electrode exhibits a high current density of 264 mA cm−2 at 1.6 V versus the reversible hydrogen electrode (RHE), outperforming state‐of‐the‐art Ni3+ catalysts. Abstract The electrocatalytic urea oxidation reaction (UOR) provides more economic electrons than water oxidation...
Fri Oct 11, 2019 18:41
Three in sequence! Three‐component radical conjugate addition of unactivated alkenes to Michael acceptors is reported. Oxidatively generated amidyl radicals act as the third reaction component which first add chemoselectively to the unactivated alkenes. The adduct radicals generated then react with the Michael acceptors to provide after reduction the three‐component products in an overall alkene carboamination reaction. Abstract Two‐component Giese type radical additions are highly practical...
Fri Oct 11, 2019 18:41
It takes two: Enantioselective synthesis of 1,4‐dicarbonyl compounds directly from readily available aldehydes was accomplished with good yield and enantioselectivity through the synergistic combination of a neutral eosin Y hydrogen atom transfer photocatalyst and a bis‐cyclometalated rhodium catalyst. Abstract Enantioenriched 1,4‐dicarbonyl compounds are versatile synthons in natural product and pharmaceutical drug synthesis. We herein report a mild pathway for the efficient enantioselective...
Fri Oct 11, 2019 18:41
The Au‐catalyzed reaction of o‐alkynylphenols with aryldiazonium salts undergoes a change in mechanism when a light source is applied. If the reaction is carried out at room temperature using a AuI catalyst, the diazonium salt undergoes electrophilic deauration of a vinyl AuI intermediate generating substituted azobenzofurans. If the reaction mixture is irradiated with blue LED light, C−C bond formation due to N2‐extrusion from the diazonium salt is observed. Abstract In a systematic study...
Fri Oct 11, 2019 18:41
Selectivity rev‐counter: The relative reactivity value (RRV) of thioglycosides is an indicator for revealing stereoselectivities for chemical glycosylation. Abstract Stereocontrolled chemical glycosylation remains a major challenge despite vast efforts reported over many decades and so far still mainly relies on trial and error. Now it is shown that the relative reactivity value (RRV) of thioglycosides is an indicator for revealing stereoselectivities according to four types of acceptors. Mechanistic...
Fri Oct 11, 2019 18:41
Expand and contract: Negative thermal expansion materials are exploited to enhance upconversion luminescence at elevated temperatures through lattice contraction and distortion. The thermally enhanced upconversion is applied in a sensitive ratiometric thermometer by referring to thermally quenched upconversion in materials with positive thermal expansion. Abstract Thermal quenching of photoluminescence represents a significant obstacle to practical applications such as lighting, display, and...
Fri Oct 11, 2019 18:41
Packed like sardines: The enantioselective preparation of acyclic carbon backbones possessing vicinal quaternary and tertiary stereogenic centers (i.e. in a 1,2‐relationship) causes distorted geometries and represents a very acute problem in organic synthesis. Several approaches are discussed in this Minireview underlining the challenges illustrated by the rather limited number of approaches available to practitioners. Abstract Overcoming the inherent difficulty to prepare quaternary carbon...
Fri Oct 11, 2019 18:41
NMR paramagnetic relaxation enhancements and residual dipolar couplings indicate that apo glutamine‐binding protein strongly favors an open conformation in solution. The findings expose serious problems in the computational study of interdomain protein motions. Abstract Glutamine‐binding protein (GlnBP) displays an apo, “open” and a holo, “closed” crystal form, mutually related by a rigid‐body reorientation of its domains. A fundamental question about such large‐scale conformational transitions,...
Fri Oct 11, 2019 18:41
Pinch‐hit: Reported here are the first functional mimics of the pincer cofactor of lactate racemase (LarA). The mimics are both structural and functional models of the pincer cofactor in lactate racemase. DFT computations suggest the ipso‐carbon atom of the pyridinium pincer ligands acts as a hydride acceptor for lactate isomerization, whereas an organometallic pathway involving nickel‐mediated β‐hydride elimination is less favored Abstract A novel nickel pincer cofactor was recently discovered...
Fri Oct 11, 2019 18:41
In tandem: A direct and atom‐economical synthesis of enantiomerically enriched vicinal diamines by the title iridium‐ or ruthenium‐catalyzed reaction of 2‐quinoline aldehydes and aromatic amines is described (see scheme). The sterically tunable chiral diamine products provided a platform for the synthesis of bulky chiral NHC ligands and can themselves serve as ligands for asymmetric transition‐metal catalysis. IPA=isopropanol. Abstract A highly enantioselective iridium‐ or ruthenium‐catalyzed...
Fri Oct 11, 2019 18:41
A whole new ball game: Porphyrins were found to act as an interfacial‐charge‐transfer mediator, like a “volleyball setter”, to efficiently suppress surface charge recombination owing to higher hole‐transfer kinetics rather than as a traditional photosensitizer (see picture). The introduction of a “setter” ensured that charge carriers had a long lifetime at the photoanode/electrolyte interface and led to increased photocurrent density. Abstract Surface recombination at the photoanode/electrolyte...
Fri Oct 11, 2019 18:41
No short circuit: A covalent triazine framework (CTF) was synthesized by the cyclotrimerization of 1,4‐dicyanobenzene using lithium bis(trifluoromethanesulfonyl)imide as a catalyst, which enables in situ growth of uniformly distributed LiF particles. Due to the lithiophilicity of the CTF backbone, interface stabilization by LiF and cavities for lithium storage provided by air‐laid paper, the resulting anode successfully alleviates Li‐dendrite growth. Abstract A new strategy for the synthesis...
Fri Oct 11, 2019 18:41
MOF carrier: A drug delivery strategy where a metal–organic framework inhibits crystallization of the amorphous drug phase and then releases the drug upon hydrolytic decomposition represents a novel approach for delivery of poorly soluble compounds while overcoming the traditional weakness of amorphous drug delivery: physical instability of the amorphous form. Abstract Encapsulating a drug molecule into a water‐reactive metal–organic framework (MOF) leads to amorphous drug confined within the...
Fri Oct 11, 2019 18:41
A peculiar radical polymerization reaction is presented in which oxygen serves as a cocatalyst alongside triethylamine. This enables far‐red activation of the PET‐RAFT process in the presence of zinc(II) (2,3,7,8,12,13,17,18‐octaethyl‐5,10,15,20‐tetraphenylporphyrin) as photocatalyst. Abstract A peculiar radical polymerization reaction is presented in which oxygen serves as a cocatalyst, alongside triethylamine, to provide activation with light in the far‐red (690 nm, 3 mW cm−2) of the PET‐RAFT...
Fri Oct 11, 2019 18:41
Graphene Oxide Modified Lanthanide Nanoprobes for Tumor‐Targeted Visible/NIR‐II Luminescence Imaging
Lanthanide‐doped nanocrystals (Ln3+‐NCs) have shown great promise in the luminescence imaging of living cells and deep tissues. However, currently it remains challenging to readily engineer hydrophobic Ln3+‐NCs with hydrophilicity and molecular recognition ability. Herein, we present an effective strategy to circumvent such a bottleneck by encapsulating Ln3+‐NCs in graphene oxide (NCs@GO). Monodisperse NCs@GO was prepared via optimizing GO size and core‐shell structure of NaYF4:Yb,Er@NaYF4, thus...
Fri Oct 11, 2019 17:49
Photobleaching is a major challenge in fluorescence microscopy, in particular if high excitation light intensities are used. Signal‐to‐noise and spatial resolution may be compromised, which limits the amount of information that can be extracted from an image. Photobleaching can be bypassed with exchangeable labels, which transiently bind to and off a target and thereby replenish destroyed labels by intact ones from a reservoir. Here, we demonstrate confocal and STED microscopy with short, fluorophore‐labeled...
Fri Oct 11, 2019 17:47
We present the first silaboration of [1.1.1]propellane, enabling direct introduction of B and Si functional groups onto the bicyclo[1.1.1]pentane (BCP) scaffold in high yield under mild, additive‐free conditions. The silaborated BCP can be obtained on a gram scale in a single step without the need for column‐chromatographic purification, and is storable and easy to handle, providing a versatile synthetic intermediate for BCP derivatives. We also describe various conversions of the C–B/C–Si bonds...
Fri Oct 11, 2019 13:19
Access control: Reversible encapsulation of CH2Cl2 or Xe in a non‐porous solid‐state molecular organometallic (SMOM) framework of [Rh(Cy2PCH2PCy2)(NBD)][BArF4] occurs in single‐crystal to single‐crystal transformations. The process is similar to the transport of substrates and products to and from the active site in metalloenzymes. Abstract Reversible encapsulation of CH2Cl2 or Xe in a non‐porous solid‐state molecular organometallic framework of [Rh(Cy2PCH2PCy2)(NBD)][BArF4] occurs in single‐crystal...
Fri Oct 11, 2019 13:03
Deposition of a monolayer nanoarray on the surface of a micrometer‐thick substrate is demonstrated, producing rectification characteristics at the nanoscale. The heterogeneity of the structure and the charge density are the two key factors affecting rectification. By altering the asymmetric electrolyte environment, the fabricated heterogeneous membrane can be used in energy conversion. Abstract The deposition of a monolayer nanoarray on the surface of a micrometer‐thick substrate is demonstrated,...
Fri Oct 11, 2019 13:01
Live show: Fluorescent activatable chemokines have been designed as the first chemical probes for in vivo detection of tumour‐associated macrophages in lung metastasis. Activatable chemokines behave as AND‐gates since they emit only after receptor binding and intracellular activation, showing enhanced selectivity over existing agents. Abstract We report the novel chemical design of fluorescent activatable chemokines as highly specific functional probes for imaging subpopulations of immune cells...
Fri Oct 11, 2019 13:00
We report the integration of surface plasmon resonance (SPR), cyclic voltammetry and electrochemiluminescence (ECL) responses to survey the interfacial adsorption and energy transfer processes involved in ECL on a plasmonic substrate. It was observed that a Tween® 80/tripropylamine nonionic layer formed on the gold electrode of the SPR sensor, while enhancing the ECL emission process, affects the electron transfer process to the luminophore, Ru(bpy) 3 2+ , which in turn has an impact on the plasmon...
Fri Oct 11, 2019 12:19
Contrast‐induced acute kidney injury (CIAKI) is a serious medical complication manifested by a rapid deterioration in renal function after administration of contrast medium into patients. Despite its high morbidity and mortality, CIAKI remains a diagnostic dilemma due to its reliance on in vitro detection of insensitive late‐stage blood and urinary biomarkers. We herein report the synthesis of an activatable duplex reporter (ADR) for real‐time in vivo imaging of CIAKI. ADR is equipped with chemiluminescence...
Thu Oct 10, 2019 20:50
Photoactive metal complexes employing Earth‐abundant metal ions are a key to sustainable photophysical and photochemical applications. We exploit the effects of an inversion centre and ligand non‐innocence to tune the luminescence and photochemistry of the excited state of a [CrN6] chromophore [Cr(tpe)2]3+ with close to octahedral symmetry (tpe = 1,1,1‐tris(pyrid‐2‐yl)ethane). [Cr(tpe)2]3+ exhibits the longest luminescence lifetime (4500 µs) reported up to date for a molecular polypyridyl chromium(III)...
Thu Oct 10, 2019 19:52
In this Review, we highlight recent advances in the understanding and design of N‐functionalized pyridinium scaffolds as single electron, redox‐triggered functional group transfer reagents. We provide a selection of representative methods that demonstrate reactivity and fundamental advances in this emerging field. Reactivity of these reagents can be divided along two divergent pathways: homolytic fragmentation to liberate the N‐bound substituent as the corresponding radical or an alternative heterolytic...
Thu Oct 10, 2019 19:51
In this work, we investigated the effect of organic ligands on the separation performance of Zr based Metal‐organic framework (Zr‐MOF) membranes. A series of Zr‐MOF membranes with different ligand chemistry and functionality were synthesized by an in situ solvothermal method and a coordination modulation technique. The thin supported MOF layers (~1µm) showed the crystallographic orientation and pore structure of original MOF structures. The MOF membranes show excellent selectivity towards hydrogen...
Thu Oct 10, 2019 17:49
Very little is known about the realm of solid‐state metal halide compounds comprising simultaneously two or more halometalate anions. Such compounds would be of great interest if their optical and electronic properties could be rationally engineered, especially the synergistic effects. Here, we report the discovery of a new example of metal halide cluster‐assembled compound (C 9 NH 20 ) 9 [Pb 3 Br 11 ](MnBr 4 ) 2 , featuring distinctly different anionic polyhedra, namely, a rare lead...
Thu Oct 10, 2019 17:49
Polyolefins are, by far, the most prevalent plastic materials with superior properties and wide applications. However, the nonpolar nature of polyolefins represents one of their biggest limitations. In this contribution, we report an efficient route to generate polar‐functionalized, crosslinkable, self‐healing and photoresponsive polyolefins with thermoplastic, elastomeric and thermosetting properties. In this approach, tunable amounts of carboxylic acid and a cyclic comonomer are installed onto...
Thu Oct 10, 2019 16:50
Iron nitrogen heterocyclic carbenes (NHC) have received a great deal of attention recently, due to their growing potential as e.g light sensitizers and photocatalysts. We present a sub‐ps x‐ray spectroscopy study of a FeIINHC complex allowing us to identify and quantify the states involved in the deactivation cascade after light absorption. We find that excited molecules relax back to the ground state populating first the 3MLCT and then along two pathways the 3MC state. One of these pathways is ultrafast...
Thu Oct 10, 2019 16:49
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