Simply by applying electricity, the amination reaction of a broad variety of arenes, heteroarenes, and benzylic substrates is achieved. Pyridine serves as the nitrogen source and the intermediate cationic species are well-protected from over-oxidation.

Let's not get together: Frustrated Lewis pairs (FLP) are combinations of Lewis acids and Lewis bases that are prevented from forming a stable adduct by steric or electronic hindrance. The growth of the field of FLP chemistry during the last four years has been rapid, including small-molecule activation, applications in catalysis, and the development of unprecedented reactions.

A photoactivatable organelle-specific live-cell imaging probe based on a 6π electrocyclization/oxidation mechanism is described. This probe is water-soluble, non-cytotoxic, cell-permeable, and can be used for mitochondrial imaging.

ZIF-4(Zn) undergoes a porous to non-porous transition on cooling from the high-temperature (HT) to low-temperature (LT) phase. The nature of this transition is elucidated by a combined approach of structure solution from powder diffraction, DSC measurement, and DFT calculations.

A well-tailored coat: As-synthesized RuO₂-coated Na₃V₂O₂(PO₄)₂F nanowires showed ultrahigh rate capability and excellent cycling stability when used as a cathode material for sodium-ion batteries.

Chromatin PNArrays: A peptide nucleic acid (PNA) targeting compound bearing a modified histone peptide was used to recruit the histone methyltransferase PRC2 to a designated site on a nucleosome array. This recapitulation of heterotypic “designer” chromatin was used to investigate how PRC2 is both activated and inhibited with respect to neighboring nucleosomes from a particular location within the array.

Nothing to get excited about: NMR spectroscopic studies revealed that a lectin with activity against the human immunodeficiency virus recognizes high-mannose sugars by conformational selection within the ground state, in contrast to the popular “excited-state” model. In the absence of sugars, both the sugar-free and sugar-bound protein conformations observed by X-ray crystallography (see picture) exist as conformational substates in solution.

The hole story: Two dimensional (2D) supramolecular polymerization of pillar[6]arenes afforded hexagonal 2D porous sheets. Carbonization of these sheets gives a carbon material containing pores with a size that is precisely controlled at the Ångstrom level by the cavity size of the precursor pillar[6]arene.

Go with the flow: Composite polymer/oxide hollow fibers have been used as a flow reactor platform for heterogeneously catalyzed reactions in organic synthesis. Embedding catalysts in the fiber walls avoids clogging of the flow channels and provides a short catalyst bed. Three different catalysts and reaction types were successfully performed in flow, thereby demonstrating the versatility of the fibers as reactors.

Iridium(III) unleashed: A cationic phenanthroline complex of Ir^III can cleave CH bonds of unactivated secondary carbons as well as benzylic carbons but not bonds to sp² or primary carbons in the gas phase. The unique reactivity pattern likely stems from the suboptimum bite angle provided by the phenanthroline ligand. Computational modeling suggests that the CH activation process is concerted, without a stable oxidative addition intermediate.

Two different mixtures: MALDI mass spectrometry and self-consistent mean-field calculations are combined to detect and predict ligand phase separation on Ag nanoparticles after synthesis. The progression of the monolayer morphology from a well-mixed random ligand distribution (see picture, left) to an intermediate degree of phase separation (right) with changes in ligand length is determined.

For the long run: Some chemotherapeutics can activate a long-term immune-mediated response against cancer by triggering an immunogenic mode of cancer cell death (ICD). A library of platinum complexes were studied, and a potent Pt-based ICD inducer was thus identified.

Carboxylic acid dissociatively self-adsorbs on metal oxide nanocrystals and can be reversibly displaced by L-type amines. Both observations are explained by an X₂ binding motif, eliminating the need for an external proton source.

Superactive nanohybrids: Cytochrome C (CytC)-loaded homogenous amyloid nanohybrids were developed. The activity of CytC is enhanced up to 450-fold in the nanohybrids compared that of unbound CytC in water. The exposed surface, morphology, and surface area of the amyloid play critical roles in modulating the enzymatic activity in organic solvents.

Don't overdo it: A palladium(II)-catalyzed CH activation cascade sequence for the synthesis of polyheterocycles is reported. Aromatization of the initially formed dihydro species occurred with a quinone oxidant. In some cases the use of one equivalent of the oxidant enabled isolation of the dihydro species as a single isomer (see scheme; X=NMe, O, S).

Amphipathic DNA origami structures were engineered, which have a flat membrane-binding interface decorated with cholesterol-derived anchors and sticky oligonucleotide overhangs enabling formation of ordered arrays on a membrane. Such DNA origami structures are capable of deforming free-standing lipid membranes (see picture), mimicking the biological activity of coat-forming proteins.

Spotlight on chromium: Selected Cr^III complexes were investigated for promoting radical cation cycloadditions. These species have sufficiently long-lived excited states to oxidize electron-rich alkenes, thereby initiating [4+2] processes. These metal complexes augment the spectrum of catalysts explored in photoredox systems, featuring properties that can result in differential reactivity from the more common Ru or Ir catalysts.

Protein–ligand complexes: A combination of the spin-diffusion-based NMR methods INPHARMA, trNOE, and STD (STI; see picture) results in an accurate scoring function for docking modes and therefore determination of protein–ligand complex structures. Applications are shown on the model system protein kinase A and the drug targets glycogen phosphorylase and soluble epoxide hydrolase.

No more smudges: A graft-copolymer-based approach was used to prepare clear polyurethane coatings that repel water, diiodomethane, hexadecane, ink, and an artificial fingerprint liquid. Different coating methods can be used to apply the coatings to different surfaces, which can thus be protected from fingerprints, stains, and graffiti.

Synthesis à la carte: A single crystal to single crystal transmetallation process is reported in a metal–organic framework in which Mg^II ions within the coordination network (see picture; orange polyhedra) and those hosted in the channels (orange spheres) are replaced entirely by either Co^II or Ni^II ions (purple spheres and polyhedra).

Lateral STM manipulations enable the controllable scission of a complicated metal–organic cluster consisting of nickel atoms and uracil molecules (see scheme, left) into its elementary structural motifs (right). Furthermore, the elementary units can be seamlessly stitched back together into the original cluster. STM=scanning tunneling microscopy.

Hydrogen-bond donors promote halide dissociation from neutral arylpalladium halides to access an enantioselective cationic pathway. The use of trialkylammonium salts in a glycol solvent enables asymmetric reductive Heck reaction of aryl halides in high stereoselectivity.

In the red: The extended π-conjugation systems of metallophthalocyanine-based conjugated microporous polymers (MPc-CMPs) results in an enhanced light-harvesting capability in the far-red region. The microporous structure of the MPc-CMPs and their excellent absorption capability for long-wavelength photons, result in them (especially ZnPc-CMP and CuPc-CMP) being promising photosensitizers with a high efficiency for ¹O₂ generation.

Doped dots: Cu–N-doped carbon dots (Cu-CDs) were fabricated by a one-step pyrolytic synthesis using Na₂[Cu(EDTA)] as the precursor. Cu–N dopants concomitantly boost the conductivity and the electron-accepting and -donating abilities of the CDs, enhancing the electron-transfer process in the photooxidation of 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate (see picture; H yellow, N blue, C light blue, O red).

Zero in: The title reaction begins with oxidative addition of R₂NOBz to a Pd⁰/PAr₃ catalyst and subsequent cleavage of a C(sp³)H bond by the generated PdNR₂ intermediate. The catalytic cycle proceeds without the need for external oxidants. The electron-deficient triarylphosphine ligand is crucial for this C(sp³)H amination reaction to occur. Bz=benzoyl.

A different cathode: The introduction of graphene as a cathode material to Li–CO₂ batteries significantly improves their performance. The resulting batteries feature a superior discharge capacity and enhanced cycle stability. A novel approach for simultaneously capturing CO₂ and storing energy has thus been developed.

Dead meat: Chemiresistive detectors for amines were created from single-walled carbon nanotubes by noncovalent modification with Co meso-arylporphyrins. The devices demonstrated sub-ppm sensitivity and high selectivity toward amines. The use of the detectors to monitor meat spoilage was also demonstrated. −ΔG/G₀=change in conductance upon exposure to meat.

A new reagent: The elusive chemical reagent CF₂HCHN₂ was generated in situ for the first time and further reacted with alkynes in a [3+2] cycloaddition reaction. This transformation constitutes a novel and efficient approach to agrochemically important difluoromethylated pyrazoles.

Interface development: The communication between enzymatic and DNA logic systems was enabled by the development of a corresponding interface.

Tumor selective: A pH-responsive zwitterionic alkoxyphenyl acylsulfonamide ligand is used to functionalize the surface of gold nanoparticles (AuNPs) to form zwitterionic NPs. The NPs reversibly become cationic at tumor pH (<6.6) with concomitant enhancement of cellular uptake and cytotoxicity in tumor cells, providing scope for pH-controlled NP delivery.

Zeolite films: Acid treatment was used to prepare stable suspensions of MFI zeolite nanosheets in ethanol. Nanosheets from these suspensions showed high surface activity and could be transferred using the Langmuir–Schaefer technique to obtain monolayer coatings (3 nm thick). Secondary growth of the monolayer coatings resulted in sub-12 nm intergrown zeolite thin films.

Openo­ to change: The simple preparation of iodonium zwitterions of closo-borates and their reactions with nucleophiles (see scheme) provided access to a broad spectrum of cluster derivatives with potential as new classes of pharmaceuticals and materials with tailored properties. The presented reactions demonstrate the synthetic versatility of closo-borate aryliodonium zwitterions.

Small but profound: In the benzannulation reaction of 1,3,8-triynes, a small structural difference has a profound impact on the structure of the products. When R is a silyl group, a nucleophile is incorporated into the newly formed benzene core, whereas when R is an aryl group, nucleophile trapping occurs at the benzylic carbon atom connected to the aryl group.

Two are better than one: The copper(II)-catalyzed aerobic oxidative coupling reaction between aryl boronic acids and anilines is significantly improved by the addition of visible-light-mediated photoredox catalysts. The substrate scope of this Chan–Lam reaction was thus expanded to include electron-deficient aryl boronic acids.

When is palladium acetate not palladium acetate? Anywhere near trace amounts of water or alcohols. Palladium acetate is extremely sensitive to hydrolysis in solution and moderately so in the solid state. The resulting hydroxide complex is likely to be the true starting point for many reactions and catalytic processes that are reported as using palladium acetate.

A quantum leap in complexity: A general strategy based on rhodium(III) azavinyl carbene intermediates was established for the oxidative [3+2]/[5+2] annulation of 4-aryl 1-tosyl-1,2,3-triazoles with alkynes. This general method provided densely functionalized indeno[1,7-cd]azepine architectures with excellent selectivity through the functionalization of two C(sp²)H bonds (see scheme; Cp*=pentamethylcyclopentadienyl, Ts= p-toluenesulfonyl).

A tale of two digermenes: The addition of acetonitrile, propionitrile, and acrylonitrile to tetramesityldigermene was examined to compare the structures of the molecular adducts with the structures of the nitrile adducts formed on the Ge(100)-2×1 surface and to provide further insight into the surface chemistry. The addition of nitriles was found to be reversible, and no evidence for cyclic ketenimines was found.

A copper-catalyzed radical/radical cross-coupling reaction enables CP bond formation by direct oxidative CH/PH coupling. During the reaction, an α-C radical species (transient radical) and a phosphorus radical species (persistent radical) were generated in the same system by using an internal oxidant. The cross-coupling of the two radical species is selective based on the “persistent radical effect”.

In control: A readily available chiral Brønsted acid was identified as an efficient catalyst for intramolecular Povarov reactions. Polycyclic amines containing three contiguous stereogenic centers were obtained with excellent stereocontrol in a single step from secondary anilines and aldehydes possessing a pendent dienophile. These transformations constitute the first examples of catalytic enantioselective intramolecular aza-Diels–Alder reactions.

A radical approach: A recently developed S_NAr reaction was used to synthesize meso-hydroxysubporphyrin, which underwent self-assembly to form a cyclic trimer. This trimer was cleaved to the corresponding meso-hydroxy monomer with a phenyl Grignard reagent. Oxidation of the monomer gave a subporphyrin meso-oxy radical species which is exceptionally stable and can be stored in solution under open air for over a month.

The modular and stereoselective synthesis of tunicamycins features a Mukaiyama aldol reaction, intramolecular acetal formation, gold(I)-catalyzed O and N glycosylation, and final N acylation as the key steps. These natural products are a unique type of nucleoside antibiotics with potent inhibitory activities against bacterial cell-wall synthesis and the N-glycosylation of eukaryotic proteins.

Reactivity studies of the thermally stable ruthenostannylene complex [Cp*(IXy)(H)₂RuSnTrip] (1) towards a variety of organic substrates are described. This complex is used for the construction of new metal–tin complexes featuring low-valent or unsaturated tin centers. IXy=1,3-bis(2,6-dimethylphenyl)imidazol-2-ylidene; Cp*=η⁵-C₅Me₅; Trip=2,4,6-iPr₃C₆H₂.

The X files: The catalytic activity of a photochemical molecular device (PMD) for light-driven hydrogen production, containing a PtX₂ (X=Cl or I) moiety as the catalytic center, is significantly enhanced by exchanging the terminal chloride ligands at the Pt center for iodide ligands. DFT calculations revealed a significantly increased electron density at the platinum center induced by the iodide ligands.

Intermediates, served up on a plate: Investigation of the formation mechanism of hexagonal Sb₂Te₃ plates (HPs) in a solvothermal synthesis shows the structure is formed in an amorphous state and then subsequently crystallizes.

Feeding of (2,3,4,5,6-¹³C₅)mevalonolactone to Hypomyces odoratus resulted in a completely ¹³C-labeled sesquiterpene ether. Its structure was elucidated by ¹³C,¹³C COSY and classic NMR experiments, resulting in a structural revision of hypodoratoxide. The absolute configuration was inferred from one of its co-metabolites. Feeding of other ¹³C-labeled mevalonolactone isotopologues confirmed skeletal rearrangements during terpene cyclization.

A successful marriage: The combination of smart hydrogels and inverse opal structures unites simplicity with efficacy for sensing macromolecules. While the inverse opal structure provides structural color and a large accessible interface for binding, the induced phase transition of the analyte-responsive hydrogel produces strong optical effects. The resulting spectral shifts can surpass 100 nm and are easily detected.

Loaded and locked: An approach to stabilizing [n]cumulenes was developed based on locking the cumulene within a rotaxane. The result is a stabilized [9]cumulene that enables the study of properties as a function of cumulene length in unprecedented detail, including by quantitative UV/Vis spectroscopy, cyclic voltammetry, and differential scanning calorimetry. The experimental results are supported by DFT calculations.