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Mononuclear complexes of certain lanthanide ions are known to have large magnetization reversal barriers caused by strong spin–orbit coupling. Now, careful tuning of the ligand field of a transition metal complex has engendered a comparable spin-reversal barrier — and in turn magnetic blocking at 4.5 K.

Benzene reduction by molecular complexes remains a considerable synthetic challenge, and typically requires harsh reaction conditions involving group I metals. Now it has been shown that a highly polar organometallic samarium alkyl complex enables the reduction of benzene to its tetra-anion without the need for a group I metal.

The ubiquity of N-heterocyclic carbenes (NHCs) in chemical research typically arises from their potent stabilizing capabilities and role as innocent spectators to stabilize otherwise non-bottleable compounds and complexes. Here, the authors reveal how NHC coordination enables selective C(sp3)–H bond scission, unlocking well-defined tin macrocycles which contrast with the typical role of NHCs in stabilizing low-valent main group centres.

Mild, controllable homocatenation of many elements is a considerable challenge, usually due to their low homonuclear σ-bond enthalpy. This is particularly difficult for boron, despite its high homonuclear σ -bond enthalpy. The controllable metal-templated catenation of four boron atoms is now demonstrated — a step towards oligomers of monovalent boron and polyboranes.

The chemistry of group 13 metals (M) is dominated by +1 and +3 oxidation states, so MX₂ species are typically metal–metal-bonded dimers, M(II)₂X₄ or mixed-valence species M(I)M(III)X₄. Now, monomeric M(II)(boryl)₂ radicals have been prepared for gallium, indium and thallium. The compounds — structurally characterized by X-ray crystallography — are stable up to 130 °C and exhibit dominant metal-centred radical character.

The oxo groups in the common trans-uranyl ion — present in the majority of known uranium compounds — are linear and inert. Now, a new reduced binuclear uranium–dioxo compound with very strong metal coupling and remarkable air stability has been formed through oxo migration and silylation.

While aromaticity is a useful concept for assessing the reactivity of organic compounds, the connection between aromaticity and on-surface chemistry remains largely unexplored. Now, scanning probe experiments on cyclization reactions of porphyrins on Au(111) show that the peripheral carbon atoms outside of the aromatic 18-π electron pathway exhibit a higher reactivity.

The inverse-trans-influence has been shown to operate in high oxidation state actinide complexes. Here, the authors report tetravalent cerium, uranium and thorium bis(carbene) complexes with trans C=M=C cores where experimental and theoretical data also suggest the presence of an inverse-trans-effect.

While silicon is a crucial semiconducting material, solution-based synthetic approaches for unsaturated silicon-rich molecules require less efficient multi-step syntheses. Here, the authors report access to soluble, polyhedral Si₉ clusters from the binary phase K₁₂Si₁₇, which contains both [Si₄]⁴⁻ and [Si₉]⁴⁻ clusters.

Carbon- and silicon-based triplet diradicals with two unpaired electrons are proposed as intermediates in organic and organometallic reactions but their isolation is challenging. Now, isolable 1,3-disilapyrroles are reported to act as organosilicon-based delocalized triplet diradicals and mediate the cleavage of the CO triple bond and C(sp³)–H bond activation.

Gaining insight on the structural transformations from atomic clusters to bulk materials is challenging. Here the authors synthesize a continuous cluster of germanium Ge₂₄⁴⁻, which can be viewed as two terminal Ge₉ units bridged via a Ge₆ central fragment, and characterize it by several techniques including X-ray diffraction; theoretical analysis indicates the presence of three aligned independent aromatic fragments.

Among the first-row p-block elements that can form neutral triple-bonded species (boron, carbon, nitrogen and oxygen), all combinations have been realized except that of boron and carbon. Here the synthesis of a neutral, uncoordinated boryne is described, closing the remaining gap in neutral first-row p-block compounds with triple bonds.

Nitric oxide, NO, has an unpaired electron and is widely used and studied in such diverse fields as biochemistry and atmospheric chemistry. Its radical nature means that singly charged species are common, but now two electrons have been added to give a radical dianion in an yttrium complex.

Probing the chemistry of transuranic elements is notoriously challenging. Now, three neptunium(III) organometallic sandwich complexes have been prepared using a flexible macrocycle as ligand, and their molecular and electronic structures characterized, adding to our understanding of the behaviour of f-elements and suggesting that the lower oxidation state Np(II) may be chemically accessible.

Metallodendrimers containing redox-robust centres are functional molecules with many potential applications. Here, the authors fabricate iron containing metallodendrimers in a range of oxidation states and investigate their interactions with, and stabilization of, gold nanoparticles.

Chiral tertiary aldols are encountered in a variety of biologically relevant molecules. Making these valuable compounds directly from unbiased ketones has proven to be extremely challenging. Now it has been shown that sub-ppm levels of in situ generated silylium-based organic Lewis acid catalysts can give quantitative product formation in very high enantiopurity through a Mukaiyama aldol reaction.

Magnesium is an ideal rechargeable battery anode material, but coupling it with a low-cost sulphur cathode, requires a non-nucleophilic electrolyte. Kimet al. prepare a non-nucleophilic electrolyte from hexamethyldisilazide magnesium chloride and aluminium trichloride, and show its compatibility with a sulphur cathode.

Bistable single-molecule magnets potentially allow information storage at extremely high densities. Here, the authors study an air- and moisture-stable mononuclear tetrahedral cobalt(II) complex, elucidating the origin of its pronounced magnetic bistability.

Computational and spectroscopic studies of molecular lanthanide complexes have implicated 4f orbitals in metal–ligand bonding interactions. Now, a comparative study of isostructural d-block, actinide and lanthanide complexes has shown that 4f-orbital covalency enables ring-opening isomerization in a Ce(IV)–cyclopropenyl complex in the solid state, a reaction not observed for the other complexes studied.

The design, synthesis and characterization of a series of circular sandwich compounds, cyclocenes, is described, and these cyclic sandwich compounds are expected to lead to further innovations in new functional organometallic materials.

In coordination and organometallic chemistry, back-bonding between an electron-rich, typically mid- or low-oxidation-state d-block metal centre and a ligand with accepting π* orbitals is widespread. Now, such an interaction has been observed between unlikely partners—high-oxidation-state uranium(v) 5f¹ ion and the poor π-acceptor ligand dinitrogen—in a U(v)–bis(imido)–N₂ complex stabilized by a lithium counterion.

Deuteration of active pharmaceutical ingredients is increasingly applied as the isosteric and isotopic replacement can modulate the pharmacokinetic profile, without necessarily having to alter the overall synthetic strategy toward the compound of interest. Here, the authors show manifold deuterations of piperidines and apply molecular rotational resonance (MRR) spectroscopy as a methodology to distinguish isotopomers within a distribution of products.

Transition-metal-catalysed additions of carbon species to aryl(alkyl)alkynes is an established and useful methodology for building towards useful molecular complexity. Here, the authors present rhodium-catalysed regiodivergent additions to aryl(alkyl)alkynes, which allows access to the uncommonly found α-addition products through modulation of the ligand choice.

So far, only homoleptic N₂ complexes of silicon have been reported under matrix-isolation conditions including but the activation of more inert nitrogen by silylenes remains challenging. Here the authors report on the activation of dinitrogen by silylenes under cryogenic conditions.

Subunits of the Elongator complex have been implicated in several nervous system pathologies. Here, the authors identify ELP2 variants in six patients with neurodevelopmental anomalies and show in mouse models that these variants impact protein stability and the activity of the complex during brain development.

Several strategies have been developed in recent years for therapeutic induction of ferroptosis in cancer. Here the authors report the design of two hypercarbon-centered gold(I) cluster prodrugs that induce ferroptosis of cancer cells, showing anti-tumor activity in preclinical bladder cancer models.

Lignin-derived 2-pyrone-4,6-dicarboxylic acid (PDC) was polymerized with various diols to produce biomass-based polyesters. The effects of alkylene spacer length on their thermal, crystalline, processability, and mechanical properties were systematically investigated. The biodegradation rate was found to correlate with the alkylene spacer length and the hydrophilicity of the polymers. Furthermore, the PDC-based polyesters exhibited strong adhesion to various metals, with adhesion strength increasing with PDC content. A maximum lap-shear strength of 15.26 MPa was achieved on aluminum.

Recently released documents give the inside story of Otto Hahn's 1944 Nobel prize in chemistry for the discovery of nuclear fission. They reveal flaws in the award-making process — and an attempt to rewrite history.

Two neutral compounds containing a zero-valent s-block metal, beryllium, have now been isolated and fully characterized. Structural characterization, supported by calculations, show that these brightly coloured complexes adopt a closed-shell singlet configuration with a Be(0) metal centre and an unusually strong three-centre two-electron π-bond across the C–Be–C unit.

Radicals of heavy main-group elements represent important intermediates in chemical synthesis, yet few have been isolated. Here the authors stabilize neutral stibinyl and bismuthinyl radicals using gallium-based ligands, and reduce the former to afford a Ga=Sb double bond-containing complex.

Exploration of molybdenum complexes as homogeneous hydrogenation catalysts has garnered significant attention, but hydrogenation of unactivated olefins under mild conditions are scarce. Here, the authors report the synthesis of a cationic Mo(II) complex, which exhibits intriguing reactivity toward C₂H₂ and H₂ under ambient pressure.

Simplified bryostatin analogues are shown to potently induce latent HIV expression in vitro. These analogues display comparable or better potency when compared with bryostatin. Moreover, they are up to 1,000-fold more potent in inducing latent HIV expression than prostratin, the current lead preclinical candidate.

Understanding Auger recombination is important for building better optoelectronics, as it is a crucial loss mechanism. Gaoet al.study it in conductive quantum dot solids, and find that it is the dominant charge carrier decay path, even for very low excitation densities.

Polygenic risk scores predict the likelihood that an individual will develop a certain cancer, however these are often specific for a given population. Here, the authors show that a risk score developed to assess the risk of breast cancer in European women can also predict risk in Asian populations.

Precursors for the release of phosphorus mononitride in solution under mild conditions have remained elusive. Now, an explosive anthracene-stabilized azidophosphine has shown PN transfer reactivity in the synthesis of an Fe–NP complex. The PN ligand is N-bonded, as the Fe–N interaction shows significant covalent character and a less unfavourable Pauli repulsion than its Fe–P counterpart.

Lanthanide sandwich complexes display interesting properties for diverse applications. Here, the authors synthesize monomeric and polymeric yttrium and erbium complexes ligated by cyclooctatetraendiide and stannolediide ligands and explore the magnetic properties of the erbium compounds.

Conversion of CO₂ into value-added chemicals by use of renewable energy is promising to achieve a carbon-neutral energy cycle. Here, the authors show that AgP₂ is a stable, selective and efficient syngas catalyst for solar-to-fuel conversion with a 3-fold lower overpotential compared to the benchmark Ag catalyst.

Despite being difficult to study, heterogenous pnictogens are an important category of catalytic materials for CO₂ conversion as their high crustal abundance and low cost offers advantages in terms of sustainability. Here the authors report group 13 functionalized Zintl clusters as homogenous atom-precise models in hydroborative CO₂ reduction.

Three decades of research in molecular nanomagnets have enabled the preparation of compounds displaying magnetic memory at liquid nitrogen temperature. Here, the authors provide an innovative framework for the design of molecular magnets based on data mining, and develop an interactive dashboard to visualize the dataset.

Attempts to bend and twist multiple bonds in order to alter their reactivities have thus far been met with only modest success. Here, Braunschweig and colleagues isolate double-bond-containing boron-based species and their 90°-twisted diradical analogs, thanks to their stabilization with Lewis basic units.

Biradical polycyclic hydrocarbons are promising materials for organic spintronic and photovoltaic applications. The efficient and scalable synthesis of a diindenoanthracene derivative that exhibits moderate biradical character, yet is remarkably stable towards oxygen and heat, is now reported. A thermally accessible magnetic triplet state was studied through variable temperature techniques.