No matter how you slice it: New insight into nanostructured materials is provided by a novel imaging technique, which reproduces the real three-dimensional (3D) fine structure of nanomaterials at the atomic level from two-dimensional (2D) projections (see scheme).

The thiyl radical of cysteine 272 (C272) in the C-P lyase adds to 5-phosphoribose-1-methylphosphonate to give a covalently bound thiophosphonate radical. Reaction with glycine 32 (G32) of the enzyme yields methane, a glycyl radical, and thiophosphate (see scheme). Intramolecular attack of the 2-OH group leads to 5-phosphoribose-1,2-cyclic-phosphate, whereas the glycyl radical oxidizes the liberated SH group back to the thiyl radical.

In the middle of things: Recent work has shown that the insertions of unactivated alkenes into the metal–oxygen and metal–nitrogen bonds of metal alkoxo and metal amido complexes can occur as rapidly or more rapidly than insertions into metal–alkyl bonds. Studies on catalytic and stoichiometric reactions occurring through this increasingly common class of organometallic reactions are reviewed.

Efforts in searching for efficient nanoparticle catalysts for the oxygen reduction reaction (ORR) in fuel cells have led to various nanoparticle (NP) systems with precise control of size, shape, composition, and structure. Whereas the traditional Pt-based catalysts are still under heavy investigation, recent studies have led to the emergence of non-Pt systems. This Review highlights the recent efforts in developing Pt- and non-Pt-based NPs into advanced nanocatalysts for the ORR.

Not noble but effective: A novel Ni/NiO/CoSe₂ hybrid material has been synthesized as an efficient catalyst for the hydrogen evolution reaction (HER; see picture). This new catalyst has a cathodic onset potential at −0.03 V, a Tafel slope of 39 mV per decade, and represents currently the best Pt-free electrocatalyst for the HER in acidic medium.

Less is more: A minimalist “clickable” photo-crosslinker (see scheme) was incorporated with numerous small-molecule kinase inhibitors. The resulting probes were used for both in vitro (cell lysates) and in situ (live cells) proteome profiling, for large-scale identification of their potential cellular kinase targets and shows improved outcomes over previous probes.

Lighting up the pancreas: A pancreatic beta cell selective probe PiY (red, see picture) was developed which stains Langerhans islets in live animals without toxicity or side effects. Through tail-vein injection, PiY allowed for a comparison of the islets between healthy and diabetic mice. PiY also facilitated the isolation of healthy Langerhans islets by using a fluorescence-guided surgical procedure.

Biradicaloids based on quinoidal rylenes! Soluble and stable tetracyanoquaterrylenequinodimethane (QR-CN) and tetracyanohexarylenequinodimethane (HR-CN) were synthesized. QR-CN has a closed-shell quinoidal structure in the ground state, whereas HR-CN has a singlet biradical ground state. Both compounds showed very strong one-photon and two-photon absorption in the NIR range.

Coaxial and orthogonal orientations of the helices (left and right illustration, respectively) in a quadruplex–duplex junction were realized by incorporating a duplex hairpin across the diverse geometries of a quadruplex. The modularity of the approach was validated through the simultaneous attachment of multiple duplex stems onto a G-quadruplex scaffold to generate a G-junction.

Stirred, not shaken: Single-line chains of 40 nm Fe₃O₄ nanoparticles can be used as the world's smallest magnetic stir bars. Their synthesis is facile and scalable. They can be introduced into picoliter emulsion droplets and turned effectively using a commercial magnetic stir plate. Because of their small size, they can resist sedimentation under gravitational and magnetic forces, thus allowing them to remain suspended and stir all parts of the solution.

Regiodivergent catalysis: Cobalt N-heterocyclic carbene (NHC) catalysts promote intramolecular olefin hydroarylation of indoles bearing an N-homoallyl or bis(homoallyl) tether and a C3 aldimine directing group to afford dihydropyrroloindoles and tetrahydropyridoindoles under mild conditions. The course of the cyclization is dependent on the tether, but can be controlled by the NHC ligand.

Holes in holes: By using a modified colloidal crystal templating method, periodically ordered macroporous architectures with controllable dual porosity are fabricated (see picture). Taking BiVO₄ as an example, these unique structures provide a platform for a better understanding of the correlation between material geometrical features and charge migration for the photoelectrochemical water splitting process.

Amines by all means: A unique aza-Rauhut–Currier/cyclization/desulfonation cascade reaction between allenoates and N-sulfonyl-1-aza-1,3-dienes, catalyzed by the readily available diamine TMEDA, has been developed. This strategy provides facile access to a broad range of valuable highly functionalized pyridines in good yields under very mild reaction conditions.

Without detours: Oxidative catalysis mediated by N-heterocyclic carbenes (NHCs) enables the direct β-carbon functionalization of saturated aldehydes (see scheme). The reaction proceeds through two sequential oxidative steps to generate α,β-unsaturated triazolium ester equivalents as formal Michael acceptors, which react with 1,3-diketones and β-ketone esters in an enantioselective manner.

An effective wake-up call: Stable α,β-unsaturated esters were activated by the addition of a chiral N-heterocyclic carbene (NHC) organocatalyst, and the resulting reactive Michael acceptor intermediates reacted with enamide nucleophiles to furnish optically pure products (see scheme; Ts=p-toluenesulfonyl). These products can be converted readily into bioactive δ-lactams, piperidines, and their derivatives.

Overriding preferences: An amine–thiocarbamate catalyst can mediate the facile, efficient, and highly enantioselective bromocyclization of olefinic 1,3-dicarbonyl compounds. In the presence of the bifunctional catalyst, the bromination occurs chemoselectively at the olefinic moiety rather than at the carbon atom in the α-position to the carbonyl units.

Moving onward and outward: MoO₃–ethylenediamine (EDA) inorganic–organic hybrid nanowires were successfully transformed into hierarchical nanosheet-based MoS₂ nanotubes (HNN-MoS₂) by anion exchange with S²⁻ anions at elevated temperature (see picture). The resulting nanotubes were highly active catalysts for photoelectrochemical hydrogen evolution by water splitting.

Enantioselectivity through H bonding: An unprecedented [4+3] annulation of enals with o-quinone methides catalyzed by N-heterocyclic carbenes (NHCs) to give benzo-ε-lactones is described. High to excellent enantioselectivity was achieved by using a chiral triazolium NHC having a free OH group, which participates in a hydrogen-bonding interaction with the substrate.

Easy peasy: The title reaction employs N-formylsaccharin, which is an easily accessible crystalline compound, as an effective CO source. The reactions proceed with a small excess of the CO source at moderate temperatures and were successfully applied to a wide range of aryl bromides. DMF=N,N-dimethylformamide, dppb=1,4-bis-(diphenylphosphino)butane.

InternAl delivery: Organoaluminum reagents activate 1,4-dien-3-ones for Nazarov electrocyclization (see scheme), then transfer a substituent to the resulting cyclopentenyl cation with moderate to complete regioselectivity and diastereoselectivity.

Drug drop off: Given that lysine-specific demethylase 1 (LSD1) could be potently and selectively inactivated by delivering phenylcyclopropylamine (PCPA), a weak and nonselective LSD1 inhibitor, directly to the enzyme's active site, a novel series of LSD1 inactivators (1) were designed. Biological and mechanistic studies indicate that 1 inhibits LSD1 potently and selectively.

The more, the better: Treatment of [Pt(H)₂(dcpe)] (dcpe=1,2-bis(dicyclohexylphosphino)ethane) with stoichiometric amounts of silane leads to the bis(silyl) complex [Pt{Si(OMe)₃}₂(dcpe)], whereas the use of an excess silane results in hydrodealkoxylations by repetitive SiO bond activation and the formation of SiH₃ ligands (see scheme; Cy=cyclohexyl).

An aryne insertion into the FSn bond of tributyltin fluoride leads to the synchronous formation of ArF and ArSn bonds to afford diverse 2-fluoroarylstannanes straightforwardly. The formal total synthesis of flurbiprofen by using a fluorostannylation product is also reported.

A simple route to complexity: An organocatalytic 1,3-dipolar cycloaddition between azlactones and methyleneindolinones provided spirooxindoles with high enantioselectivity (see scheme). This transformation takes advantage of the nucleophilic C4 and electrophilic C2 atoms in the azlactone substrate. Bn=benzyl, HOBt=1-hydroxy-1H-benzotriazole, MTBE=methyl tert-butyl ether, PG=protecting group, TMS=trimethylsilyl.

A picture of (non)innocence: Non-innocent and bulky phosphanes bearing a reducing cycloheptatrienyl–cyclopentadienyl titanium moiety swiftly convert Pd^II into Pd⁰ species at room temperature (see scheme). The resulting complex catalyzes the Suzuki–Miyaura coupling with fast conversion even of sterically hindered aryl bromides.

Tube in a tube: A general strategy for the fabrication of novel complex tube-in-tube nanostructures for many metal oxides has been developed. The method involves coating carbon nanofibers with a layer of metal glycolate followed by calcination in air. The unique complex tubular structures of metal oxides are shown to exhibit promising properties for the title applications.

Carbocyclic cage fight: The substrate-controlled total synthesis of vinigrol features a strategic oxidative dearomatization/Diels–Alder cycloaddition reaction and a subsequent palladium-catalyzed cyclization cascade to construct the carbocyclic core. The C4, C9, and C12 stereocenters were installed using either reduction or oxidation reactions, and the diterpenoid core was unraveled by a ring fragmentation reaction.

These cats are purrfectionists: The ChenPhos ligands (see structure) showed dramatically higher catalytic activity in the title reaction than their C₂-symmetric predecessor with two dimethylaminoethyl-substituted ferrocenyl(phenyl)phosphanyl groups. The ready accessibility, extreme air stability, and high enantioselectivity, activity, and productivity of these ligands make them very promising for a wide range of practical applications.

By design: The site-selective oxidation of unactivated secondary CH bonds was accomplished with hypervalent iodine(III) reagents and tert-butyl hydroperoxide (see scheme). The preparation and derivatization of the hypervalent iodine(III) reagent are simple, thus allowing the rational design of these reagents to optimize the site selectivity of the oxidation.

Iron works: Enantioselective nitrene transfer to sulfide was accomplished by a chiral iron(III)/PyBOX catalyst (see scheme). Various sulfimides were thus obtained in high enantioselectivities and yields. Applications of this protocol to the syntheses of enantioenriched sulfoximines and an epoxide were also demonstrated.

A molecular switch: The conductance of a new molecular device based on graphene–molecule junctions was reproducibly switched between open and closed states under irradiation of external light (see picture). Three photochromic diarylethene derivatives with different substituents were used as key elements of the molecular devices.

Crystal sweets: Polysaccharide synthesis is hampered by many factors. These problems can be circumvented by the crystal-to-crystal azide–alkyne cycloaddition polymerization of an unprotected monosaccharide, which gives a crystalline glycopolymer regiospecifically in quantitative yield.

Domino cyclization: Alkylpalladium intermediates in an asymmetric Heck reaction were intercepted by a second alkene to give tricyclic products with high enantioselectivity (see scheme; Boc=tert-butoxycarbonyl). The method was applied to the asymmetric synthesis of a precursor of (−)-martinellic acid, a folk eye medicine in South America.

A photocatalyst ([Ru(bpy)₃]²⁺) bound to a protein ligand was essential for the title method. Local single-electron transfer from the catalyst resulted in the formation of tyrosyl radicals. N′-Acetyl-N,N-dimethyl-1,4-phenylenediamine was used as the tyrosyl radical trapping agent and used in a radical addition to afford selective modification of the target protein.

Metallic impurities: Graphene oxide nanoribbons (GONRs) are commonly synthesized using carbon nanotubes (CNTs) as a precursor (see picture). The CNTs contain significant amounts of metallic impurities even after purification. These impurities persist after oxidative opening of the CNTS to GONRs and heavily influence the electrochemical behavior of the resulting material.

Electron-transfer (ET) rates are measured by use of time-resolved EPR spectroscopy, involving photooxidation of nitroxyl radicals by a ruthenium bipyridyl complex. This permits acquisition of the fundamental characteristics of ET in solution. The method was used on two spin-labeled derivatives of bacteriorhodopsin, and is applicable to proteins, nucleic acids, and biological membranes.

Zeolite membranes: A promising method is reported for the fabrication of oriented silica MFI zeolite films (see picture; TPAOH=tetrapropylammonium hydroxide). The films synthesized by using this method exhibit an outstanding performance for the separation of p- and o-xylene.

Chemical cross-linking was used to prepare DNA nanostructures with enhanced thermal stability. These thermostable DNA nanostructures were then utilized as modular primers in the polymerase chain reaction (PCR; see picture), thus enabling the production of multifunctionalized and branched PCR products for multiplexed detection and hydrogel formation.

Cutting costs, cutting corners: In an inexpensive and straightforward synthesis of syn-propionamide aldols, formation of the Z enolborinate by the hydroboration of 4-acryloylmorpholine with diisopinocampheylborane ((Ipc)₂BH) was followed by aldol reactions with achiral and chiral aldehydes to provide syn-α-methyl-β-hydroxymorpholinecarboxamides with excellent enantio- and diastereoselectivity (see scheme; R=alkyl, alkenyl, aryl, heteroaryl).

Ice to see you: The Stenocara beetle in the Namib Desert collects drinking droplets from the morning mist using its waxy wings, which are tailored with sub-millimeter hydrophilic humps. Superhydrophilic graphene oxide nanoflakes are biomimetic analogues of these humps and can seed ice nucleation on hydrophobic graphite. Various ice solids can thus be grown at ambient conditions (see images).

Exploring the stacks: Two different but related naphthalene compounds were shown to form different nanostructures (see picture) depending on the π–π stacking and hydrogen bonding of the molecules. These nanostructures had unique photonic confinement and light-propagation characteristics, which show potential for nanophotonic circuits.

Imaging of chirality domains: Resonant circularly polarized X-ray diffraction distinguishes crystalline enantiomers (see picture). Control of the penetration depth and microfocusing of X-rays leads to a new visualization technique of the three-dimensional chirality-domain morphology, providing support to the increasing demand for the improvement of inorganic chiral crystal engineering.

From blue to red: The structure and luminescence properties of the gadolinium(III) complex 1 were investigated. Reversible switching of the luminescence of 1 in THF at room temperature by alternating light irradiation and O₂ exposure is presented, during which the emission color changes as shown in the picture. Light-induced phosphorescence of 1 plays a key role in this behavior.

Sequences of high resolution low-temperature emission spectra from individual light-harvesting 2 (LH2) complexes from Rhodopseudomonas acidophila reveal a much larger variety of the emission profiles than previously observed. The results provide direct evidence for substantial variations in electron–phonon coupling and concomitantly of exciton (de)localization within single pigment-protein complexes.

Ruthenium and Co: Ruthenium(II) complexes remain prime candidates for dye-sensitized solar applications; however, current ruthenium sensitizers are not compatible with cobalt(II/III) electrolytes. Herein, the effect of surface insulation on device efficiency is studied by comparing two cyclometalated tris-heteroleptic ruthenium(II) complexes. This approach demonstrates a general principle that leads to unprecedented efficiency for a ruthenium(II) sensitizer used in combination with a cobalt electrolyte.

Will the real viridicatumtoxin B please stand up: The total synthesis of viridicatumtoxin B resulted in its structural revision and opens the way for analogue construction and biological evaluation of this complex tetracycline-like antibiotic. The highly convergent strategy employed allows for swift construction of the entire carbocyclic framework of the molecule.

Gold or CdS nanoparticles and ionic dye molecules can form supramolecular assemblies with a defined size between 100 to 300 nm when using a macro-ion as template and connector. The picture shows the arangement of gold, dendrimer, and dye in the hybrid assembly (blue sphere: dendritic macro-ion, red spheres: gold, red bars: ionic dye).

Bigger is better: Sequential backbone assignments are obtained by NMR spectroscopy for a 1 MDa proteasome complex. The method relies on immobilization of a soluble protein complex by magic-angle spinning. Deuteration and proton detection of exchangeable sites and paramagnetic relaxation enhancement enables exploration of structural and dynamic properties of supramolecular assemblies at atomic resolution.