Neue makrozyklische Arene, sogenannte Prism[n]arene, werden leicht aus 2,6-Dimethoxynaphthalin und Paraformaldehyd in Gegenwart von Templaten synthetisiert. Sie haben eine prismenartige Struktur mit elektronenreicher Kavität und zeigen exzellente Bindungsaffinitäten für organische Kationen. Mit ihrer einfachen Synthese und guten Wirt-Gast-Chemie sollten sich zahlreiche Einsatzmöglichkeiten in der supramolekularen Chemie finden lassen.

Analysis of the use of differential scanning calorimetry (DSC) for thermal hazard assessment in 2019 shows some alarming trends. Many reports are not reproducible, do not follow established best practices and the conclusions drawn are not supported by the data presented. This Viewpoint discusses these issues and offer simple guidance on how to avoid them.

Multifaceted materials: Interface assembly enables the integration of magnetic particles and mesoporous materials to form advanced core–shell magnetic mesoporous materials for a variety of applications in catalysis, environmental remediation, and biomedicine. This Minireview summarizes progress made in the synthesis of core–shell magnetic mesoporous silica and the adjustment of key parameters, including pore size, morphology, and pore orientation.

Die DNA-Nanotechnologie hat eine große Auswahl an biomedizinischen Nanostrukturen hervorgebracht, jedoch sind diese DNA-Nanostrukturen häufig nur begrenzt stabil und äußerst immunogen. Dieser Aufsatz behandelt biomedizinische Anwendungen von DNA-Nanostrukturen, beschreibt die Herausforderungen, denen DNA-Nanostrukturen in der physiologischen Umgebung gegenüberstehen, und diskutiert Lösungsansätze.

V for Vanadium: A drastic decrease in cytotoxicity of a mixed-ligand V^V complex 1 after its decomposition in biological media can be employed in intratumoral injections, particularly for brain cancer. The release of relatively non-toxic V decomposition products into the blood is expected to reduce the side effects and may also be beneficial due to the known neurostimulatory properties of V.

Functional microcapsules for stable lithium metal anodes (LMAs) have been designed based on double-shelled C@MoS₂ nanostructures preloaded with sulfur. The as-prepared C@MoS₂/S structures can provide a long-term supply of polysulfides, which serve as an effective additive for improving the stability of the solid electrolyte interphase on the LMA, thus prolonging the cycle life.

Water-soluble polymers for HER: As inspired by enzymes, three water-soluble polymers with appending Co porphyrins and different side-chain groups are designed. These catalysts show high activity and stability for electro- and photocatalytic HER in neutral aqueous solutions. With the same Co porphyrin, the activity can be fine-tuned by using different side-chain groups.

The small print: Co-N-C single-atom catalysts were derived from metal– organic frameworks and compared with related nanoparticles in the selective dehydrogenation of formic acid. The highly dispersed single Co^IIN_x sites demonstrated improved reactivity and resistance to acid, constituting the current state-of-the-art in low-cost earth-abundant catalysts for this transformation.

Listen to HER tune: Regulating charge transfer by doping with single transition-metal atoms and making oxygen vacancies on a TiO₂ nanosheet is reported. These approaches modulate the activity of the lattice oxygen atom in titania, providing a way to tune and thus optimize catalysis of the hydrogen evolution reaction (HER).

Properly aligned: Residual dipolar couplings and residual chemical shift anisotropies can be acquired from natural products without special sample preparation using magnetically induced alignment. On the basis of two examples—the novel natural product gymnochrome G and the alkaloid strychnine—these data, together with the predicted alignment, yield the correct configuration with high certainty.

Full speed ahead: Ultrafast spectroscopy revealed that photoinduced polarization switching in the crystal of a [CrCo] dinuclear complex proceeded with a time constant of 280 fs (see picture; LT/HT=low-/high-temperature, dhsq/dhbq= deprotonated dihydroxysemi-/benzoquinone). The pronounced appearance of a low-frequency coherent vibration and its mechanism suggest that the corresponding excited-state vibrational mode facilitates the polarization switching.

A new route to the classical ylide Ph₃As=CH₂ resolves previous difficulties in its synthesis and isolation. Its structural authentication, 45 years after it was first made, confirms that the ylide is pyramidal not planar, and it enables the synthesis of a uranium–arsonium–carbene, the first structurally characterised example of an arsonium–carbene complex of any metal.

The absolute configuration of difficult-to-crystallize small molecules can be obtained by rapid thermal co-crystallization with TEO, a tetraaryladamantane octaether, and X-ray crystallography. As little as 3–5 mg of analyte can produce both NMR and diffraction data within 48 hours.

Double helices and other hierarchical structures of elemental phosphorus can be built from the simple P8 cage. Machine-learning-driven and fragment-based searches enable a rapid exploration of structural space, and dispersion-corrected DFT computations reveal the resulting structures to be more stable than white phosphorus.

A biocatalytic photoelectrochemical platform for solar-assisted dual biotransformations is constructed by wiring a Mo-doped BiVO₄ photocathode and a hierarchical porous ITO electrode. The deliberate integration of enzymatic redox processes into the photoelectrochemical cell simultaneously facilitates peroxygenase- and ene-reductase-mediated enantioselective synthesis of high-value chemicals using solar-powered electrons and water.

Flow with it: Dehydrative amination of phenols under continuous-flow conditions has been developed. In an integrated packed-bed flow system containing heterogeneous Pd catalysts, phenols reacted with amines to generate aryl amines and small amounts of easily removable co-products. The method has high product selectivity and excellent functional-group tolerance, so that variously substituted aryl amines can be selectively prepared in high yields.

More confusion?! In the copper complex of dicarbacorrole (referred to as N^Norrole), the lone pair electrons in the N(sp²)–N(sp²) linkage in the circuit played a crucial role in the global 18π conjugation circuit due to Hückel aromatic stabilization. The resulting NNCC coordination core in copper facilitated the upshifting of the Cu 3d_x2–y2-dominant orbital to afford a singlet organocopper species.

Ligand-like, polyvinylpyrrolidone molecules stabilize single-atom Pt during UV-induced photoreduction on titanium oxide nanorods encapsulated by graphitic carbon. The resulting material shows extremely high activity toward the hydrogen evolution reaction.

A non-alternant isomer of terrylene bisimide was synthesized by palladium-catalyzed [3+3] annulation of azulene and naphthalimide. It was functionalized by simple bromination and nucleophilic substitution. These π-extended azulenes show NIR absorptions and planar geometries with an aromatic azulene moiety, as confirmed by crystallographic analysis and theoretical calculations.

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.

May I interrupt? Taking advantage of the interrupted Pummerer reaction, trifluoromethyl sulfoxides engage in the metal-free C−H trifluoromethylthiolation of (hetero)arenes, including drug molecules and natural products. This new class of trifluoromethylthiolating reagent exploits a new strategy for trifluoromethylthiolation in which sulfonium salts are assembled and selectively deconstructed.

Electron-transfer driven molecular compression: The first X-ray crystallographic characterization of the reduced forms of benzo-fused double[7]helicene (1) ranging from 1²⁻ to 1⁴⁻ reveals a gradual core change upon stepwise multiple electron charging.

A trans-selective alkyne cyanoboration debuts! A Pd complex supported by an 1,4-azaborine-derived phosphine ligand is uniquely capable to transform 1,3-enynes into tetra-substituted borylated dienenitriles with high site-, regio-, and trans-diastereoselectivity.

Catalyzed by CuPd’s arrow: CuPd nanoparticles are used as a robust catalyst for the electrochemical reductive allylic alkylation reaction in aqueous solution.

A N-hetero-Rh^I-metallacyclic silanone has been synthesized. This silanone is stable in solution at 60 °C and only slowly isomerizes at 120 °C, via an intramolecular C(sp³)−H bond insertion. This Rh^I-substituted silanone can react either on the Si=O function or the Rh center, depending on the type of reagents.The reaction with H₂, resulting in the hydrogenation of silanone moiety, proceeds via cooperative involvement of both sites.

Bringing DNA into the fold: A foldable polymer DNA origami assembled using T-junction motifs is presented. It is shown that a set of just two interaction rules can be used to assemble simple T-junction origami motifs and that assembly can be performed at room temperature.

Caging an Fe(II) ion: Like a cube the fourfold interlinked bisterpyridine ligand surrounds the Fe(II) ion. The post-coordinative macrocyclization rigidifies the ligand sphere and guaranties the preservation of the properties of the complex.

Molecular diffusion ultimately determines the sensitivity of gas sensors, whose driving force is directly proportional to the analyte concentration gradient. When the vertical diffusion was switched to the integration of vertical and horizontal diffusion, the gas sensors fabricated on patterned arrays displayed an order of magnitude higher sensitivity than their counterpart film-based sensors.

Step by step: A well-defined graphene-like 2D polymer with a wide band gap has been fabricated on Au(111). Distinct stepwise on-surface reactions, including alkynyl cyclotrimerization, C−O bond cleavage, and C−H bond activation, were triggered on demand, leading to product evolution in a controlled step-by-step manner.

Quantitative generation of hetero-chromophore dimers is realized through cucurbit[8]uril-directed self-sorting, favored by the introduction of designed, shape-complementary moieties. This process results in discrete heterodimeric stacking through supramolecular confinement, enabling efficient interchromophoric energy transfer upon photoexcitation.

The exsolution of CoFe alloy nanoparticles in La_0.4Sr_0.6Co_0.2Fe_0.7Mo_0.1O_3−δ perovskite is investigated at atomic scale using in situ scanning transmission electron microscopy with energy dispersive X-ray spectroscopy and density functional theory calculations.

Ironing imines: The first iron-catalyzed asymmetric reduction of N-alkyl imines is reported. A molecularly defined iron complex catalyzes the highly enantioselective hydroboration of various N-alkyl imines, providing access to the corresponding α-chiral amines in high yields and stereoselectivities. The earth-abundant metal catalyst was applied in the synthesis of the pharmaceuticals Fendiline and Tecalcet.

New optics: The first fluorosulfonic ultraviolet (UV) nonlinear optical (NLO) material, C(NH₂)₃SO₃F, is rationally designed by taking KBe₂BO₃F₂ (KBBF) as the parent compound. C(NH₂)₃SO₃F is a metal-free UV NLO crystal that benefits from the coplanar configuration of the C(NH₂)₃⁺ cationic groups, and it possesses a large second harmonic generation response of 5×KDP and a moderate birefringence of 0.133@1064 nm.

Vitamin K for Al: Attempts to enhance the reactivity of a β-diketiminate AlI complex by addition of a potassium reagent led to ligand deprotonation, yielding a different highly reactive anionic AlI complex. Addition of benzene gave two C−H bond activations exclusively in para-positions.

Cyclometalated iridium(III) complexes were developed as mitochondria-targeted three-photon phosphorescence agents for confocal imaging and phosphorescence lifetime imaging. The agents can be used from monolayer cells to the living body, with both large penetration depth and great resolution at an excitation wavelength of 980 nm.

Gaining ground: Optical excitation of spiropyrans quantitatively transforms them into merocyanines with a strong intramolecular charge-transfer (ICT) emission. The gain region of the merocyanine isomers shifted with photoisomerization because the increased polarity of the molecular environment lowered the ICT energy levels. Broadband-tunable single-mode lasing was achieved based on the controllable ICT processes in polymeric coupled microdisks.

Caught in a web: Inspired by the similarity of the 3D structure of superb-uranyl binding protein SUP to that of spidroin from spider silk, a chimeric protein, DSUP, containing two copies of SUP was designed and spun into protein fiber. Impressively, the high-strength DSUP fiber shows ultrahigh, ultrafast, and highly selective uranium extraction ability in natural seawater.

Die Synthese von Tetraalkylammoniumtetrafluoridochlorat(III) wird beschrieben. In Acetonitril wird ein Chloridsalz bei tiefen Temperaturen mit verdünntem Fluor umgesetzt. Anwendungen des [ClF₄]⁻-Salzes werden durch die Überführung von Ph₂S₂ in PhSF₅, den Austausch der CN-Gruppen in Acetonitril und Tetracyanoborat in CF₃-Gruppen, die Reaktion mit CO zu Fluorphosgen und die Bildung des Tetrafluoridoaurates [AuF₄]⁻ aus elementarem Gold untersucht.

Radikal-Rotationen um Si-P-Bindungen: Myonium, ein leichteres Isotop von H, reagiert mit Phosphasilenen zu P-zentrierten und/oder Si-zentrierten Radikalen. In manchen Fällen können mehrere Rotamerkonformationen desselben Radikals nachgewiesen werden, je nach Art der Substituenten des verwendeten Phosphasilens.

Encapsulation of a trinuclear Fe^III₂Fe^II complex within channels of a unique MOF is leading to the generation of iron nanoclusters stabilized on the carbon layer. To inhibit the aggregation of iron atoms toward nanoclusters, a „heteroatom modulator approach“ is developed by atomic replacement of Fe^II by Zn^II/Co^II. A stable iron dimer in an optimal metal–nitrogen moiety is synthesized as efficient oxygen evolution catalyst.

Pretarget then activate: Functionalization of single-walled carbon nanotubes (SWCNTs) with tetrazines led to a stable and biocompatible material that undergoes a rapid inverse-electron-demand Diels–Alder reaction with trans-cyclooctene caged molecules. This approach enables bioorthogonal activation of responsive drugs or probes in solid tumours in a strictly controlled manner.

Stability: Despite the excellent optoelectronic properties of halide perovskites, their stability under ambient conditions and, more importantly, in aqueous medium are poor, thus limiting their application in solar photoelectrochemical (PEC) devices. Reported here is an extremely stable vacancy ordered halide perovskite, Cs₂PtI₆, which is stable for at least one year under ambient conditions and for 24 hours in extreme pH conditions. It also demonstrated 12 hours of solar PEC water oxidation, without any surface protection.

The bimetallic Rh-In catalyst offers selective sites for capturing hydrogen and CO₂ to approach methanol formation under H₂-deficient feedstock compositions with high methanol yield but minimizing the reverse water-gas shift reaction. Using this catalyst, a convenient methanol synthesis based on renewable biomass-derived feedstocks with lower energy costs can be established.

Passing through: Reported for the first time is the successful in situ biomineralization of an enzyme-containing metal–organic framework (MOF) layer on a polymeric hollow fiber in a facile one-step process. The interconnection between an enzymatic active layer and a porous membrane overcomes stability drawbacks, removes the need for MOF separation, and leads to increased enzyme activity as a result of the improved mass transport by permeation.

Multicolor swap shop: A facile doping approach for color-tunable organic phosphorescence materials is enabled through hosts that not only restrict the molecular motion and avoid the triplet quenching from the oxygen, but also interact with the guests for the realization of phosphorescence. Color tunable, temperature dependent, and time-resolved anti-counterfeiting techniques are achieved by the printable and writable materials.

Dual-stress and thermally responsive crystalline metal–organic materials (MOMs) based on molecular spring-like triple-helix coordination polymers are presented. As the first example of thermosalient effect in elastic MOMs, these compounds undergo elastic flexure upon external stress as well as cracking and jumping after thermal treatment.

By developing a new generation of pantetheine analogue probes, the metabolic labelling and chemoproteomic profiling of protein 4′-phosphopantetheinylation in mammalian cells were achieved. Targeted chemical proteomics facilitated the identification of exact 4′-phosphopantetheinylation sites, including all five currently known sites and a potential site in the mitochondrial dehydrogenase/reductase SDR family member 2 (DHRS2).

The direct transformation of readily available phenol derivatives into valuable trifluoromethylarenes was developed. The PMe₃-catalyzed oxidative addition and transmetalation, as well as CCl₃CN-induced reductive elimination play key roles in this successful nickel-mediated trifluoromethylation.

Force to be reckoned with: The correlations between nanoscale electrical, chemical, structural, and mechanical surface properties were explored in perovskite and amyloid fibrils with intrinsically integrated peak force infrared and Kelvin probe force microscopies. Correlative nanoimaging serves as a useful tool for deciphering the important underlying causal relationships between properties in situ.

Emissive silver nanoclusters formed with cytosine-loop hairpin DNA sequences self-assemble as highly emissive dimers exhibiting a head-to-head interaction interface. These dimeric species only form emissive dimers when synthesis is initiated from DNA in the monomeric hairpin conformation. The orange emissive AgNCs were found to be composed of 12 Ag per dimer with the dimerization mediated by the nanocluster.

Imaging the electrocatalytic process: The cobalt-phthalocyanine-catalyzed CO₂ reduction reaction is investigated by electrochemical scanning tunneling microscopy at the molecular scale. The molecular processes of the reaction, including the reduction of Co^II, the binding of CO₂, and the subsequent process, are revealed.

Go with the glow: A two-step process has been developed that transforms parent diketopyrrolopyrrole into structures with up to 10 fused rings. The absorptions are bathochromically shifted to the deep-red region and strong red emission is seen, even in nonpolar solvents, despite the presence of NO₂ groups.

PDT with a twist: The intersystem crossing (ISC) mechanism of a heavy atom-free helical bodipy derivative was elucidated. Due to the intense absorption at long wavelengths (ϵ=1.76×10⁵ m⁻¹ cm⁻¹ at 630 nm), satisfactory triplet quantum yield (Φ_T=52 %), and long-lived triplet state (τ_T=492 μs), a record low-dose photodynamic therapy (PDT)-augmented immunotherapy was achieved.

Protein heterocatenanes could be readily and modularly synthesized in cellulo using a programmed sequence of post-translational processing events, including intramolecular chain entanglement, in situ backbone cleavage, and spontaneous cyclization. The catenane topology of the designed protein was rigorously proven by X-ray crystallography.

It takes two: CuH/Pd-catalyzed enantioselective hydroarylation of 1,1-disubstituted alkenes proceeds with anti-Markovnikov regioselectivity under mild conditions to access β-stereogenic arenes. A wide range of aryl bromides, including several heterocycle-containing substrates, can be used with good efficiency and enantioselectivity. Various 1,1-disubstituted alkenes were also examined.

Well balanced: A fullerene-based molecular torsion balance is constructed to investigate noncovalent arene–fullerene interactions. The interactions are weak but measurable. The linear correlation between the difference in the free energies of two well-defined conformers and the Hammett constants of the substituents on the arene moieties indicate that the electrostatic interactions are a significant contribution.

The first THF-soluble Ln^III-in-cryptand complexes synthesized by using lanthanide triflates were chemically reduced using KC₈ to generate a Sm^II-in-cryptand complex and the first neutral Nd^II-in-cryptand complex. Experimental and theoretical analysis assign the Nd^II ion a 4f⁴ electron configuration opposed to a 4f³5d¹ electron configuration.

Reactivity pathways of NacNacAl with various N-heterocycles have been investigated and diverse and highly substrate-controlled reactivity patterns have been discovered. Cases of unusual sp³ and sp² C−H bond activation, C−C coupling, and N−N bond cleavage are reported. NacNac=[ArNC(Me)CHC(Me)NAr]⁻, Ar=2,6-iPr₂C₆H₃.

Triple threat: A mitochondria-targeting probe switches on in three different fluorescence modes in response to H₂O₂, protein, and nucleic acids, enabling the visualization of mitochondrial nucleoprotein dynamics. Super-resolution imaging reveals that the proteins localize at mitochondrial cristae and largely fuse with nucleic acids to form nucleoproteins, whereas increasing H₂O₂ levels lead to disassociation of the nucleoproteins.

For your dyes only: Bis-metallation of expanded porphyrin analogues induced a remarkable d_π–p_π molecular-orbital mixing that resulted in extremely narrow HOMO–LUMO gaps. The metal-complex dyes exhibited emissive and photoacoustic properties in the third near-infrared region (NIR-III) beyond 1500 nm.

Isolation for activity: A solid co-catalyst with monomeric Al sites for Ni-catalyzed ethene dimerization was prepared by grafting Al(CH₂^tBu)₃ on partially dehydroxylated silica and characterized by ²⁷Al solid-state NMR spectroscopy augmented by DFT computations. The efficient co-catalytic properties of the material were attributed to the presence of monografted alkylaluminum species, representing 19 % of all Al species.

Pdots and moonbeams: By controlling the population of photogenerated holes, dual-mode superresolution imaging with semiconducting polymer dots was demonstrated. The localization precision achieved is 3–8 times better than the typical resolution obtained by localization of dyes and fluorescent proteins, which allows the hollow structure of microtubules to be resolved.

Upcycling: A sixfold trichlorosilylated butadiene dianion is accessible in one step from hexachlorobutadiene and the Si₂Cl₆/Cl⁻ system. Cl⁻ abstraction with AlCl₃ causes a double cyclization reaction and quantitatively forms a six-membered double silacyclobutene.

Ultramicropore control of molecular sieving in two forms of calcium trimesate leads to the first non-membrane solid that serves as a molecular sieve for H₂ over slightly larger gas molecules, including CO₂ and N₂.

The anisotropic Poisson effect of an elastic 9,10-dibromoanthracene single crystal was observed. The macroscopic anisotropic Poisson effect is well consistent with microscopic anisotropic Poisson effect in the level of molecular packing structure that was simulated by DFT calculations. Its bending and stretching deformation-induced fluorescence changes were observed as well.

Without transition metal catalysts, diazo quinones undergo cross-coupling with catechol boronic esters to give a variety of biaryls and alkenyl phenols in up to 96 % yield under mild conditions. The reaction is applicable to the synthesis of multi-substituted triphenylenes and natural products honokiol, moracin M, and stemofuran A. DFT calculations revealed a stepwise mechanism involving attack of the boronic ester by a singlet quinone carbene.

Heptazine-based C₃N₄ photocatalysts with heteroatom dopants exhibit potassium-induced interlayer charge separation and local charge polarization on sulfur sites. This facilitates O₂ adsorption and the subsequent two-electron reduction of dioxygen to achieve highly efficient and selective production of H₂O₂ up to a millimolar level per hour and 100 % apparent quantum yield at 420 nm.

The biotransformation of the neonicotinoid pesticide sulfoxaflor and the metabolic responses in Sprague-Dawley rats was investigated. Sulfoxaflor transformation was catalyzed by cytochrome P450 while five phase I and four phase II metabolites were identified in vivo. Exposure to sulfoxaflor caused dysregulation of bile acid synthesis and reabsorption by the expression of farnesoid X receptor (FXR).

Wie süß? Quantifizierung der N-Glykosylierung auf Basis von Massenspektren des intakten Proteins wird durch Glykierung verfälscht, was besonders im Zusammenhang mit Biopharmazeutika problematisch sein kann. Eine neue rechnergestützte Methode kann diese Verfälschung korrigieren.

Gemeinsam etwas bewirken: Der Einbau von Heteroatomen in spirokonjugierte Triangulene und die damit verbundene Struktur-Eigenschafts-Beziehung wurde untersucht. Im Fokus stehen die molekulare und elektronische Struktur, die duale Fluoreszenz (Kern und Seitengruppen) und das Aggregationsverhalten in Solvens-Antisolvens-Gemischen.

Die Iodierung von cyclo-E₅-Komplexen zur Synthese von Polypnictogen-Komplexen wird vorgestellt. Bei der Reaktion von [Cp*M(η⁵-P₅)] (M=Fe, Ru) mit Iod wurden [Cp*MP₆I₆]⁺-Kationen mit tripodalen cyclo-{P(PI₂)}₃-Liganden gebildet. Bei cyclo-As₅-Komplexen wurden der erste dikationische Fe-As-Tripeldecker-Komplex, der erste monokationische Ru-As₅-Tripeldecker-Komplex und zwei Isomere eines Komplexes mit einem einzigartigen Tetramer von Iodarseniden-Einheiten gebildet.