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The development of highly efficient electrocatalysts for the ethanol oxidation reaction (EOR) is critical to the commercialization of direct ethanol fuel cells, which represent a promising clean energy technology. 2D palladium metallenes (Pd MLs) have recently emerged as attractive electrocatalytic materials with the potential to replace conventional Pt-based catalysts, owing to their exceptionally high surface-to-volume ratio. However, the practical application of Pd MLs requires the construction of efficient active sites and the mitigation of stability issues associated with their defective structures. In this study, a defect-site activation strategy is proposed involving the anchoring of single iridium (Ir) atoms onto the high-strain defect regions of ultrathin Pd MLs, which significantly enhances their EOR performance. The optimized catalyst, Ir_0.59/Pd ML, featuring atomically dispersed Ir, achieves a remarkable mass activity of 1085.45 mA mg⁻¹ toward EOR—≈ 12.8 times higher than that of pristine Pd MLs. Detailed mechanistic studies indicate that the enhancement arises from the formation of synergistic PdIr sites within the defect regions. These sites concurrently improve both EOR activity and poison tolerance through electronic modulation. This work demonstrates the potential of atomic-level engineering of intrinsic defects in metallene materials for the rational design of advanced 2D electrocatalysts.

The oxygen reduction reaction (ORR) is a key process in energy conversion devices such as fuel cells and metal-air batteries, yet its slow kinetics significantly limit overall performance. Current ORR practicality largely relies on the utilization of platinum-group metals, facing challenges in scarcity, high cost, and poisoning tolerance. Iron–nitrogen–carbon (Fe–N–C) catalysts have emerged as promising platinum-group-metal-free alternatives due to their low cost, tunable structure, and strong ORR activity in pH-universal environments. These atomically dispersed Fe–N_x sites have wide tunability in electronic state and local coordination, exhibiting great potential in activity/stability enhancement and selectivity switching. However, challenges such as Fe leaching, carbon corrosion, and the formation of inactive phases limit their durability. This review outlines the main factors influencing the activity and stability of Fe–N–C catalysts and summarizes recent strategies for improvement, including dual-metal doping, porosity engineering, advanced synthesis methods, and protective encapsulation. These insights provide a pathway for designing next-generation ORR catalysts for sustainable energy applications.

A boron-catalyzed direct α-aminoxylation of carboxylic acids is developed, providing rapid access to unique β-amino acid analogs, namely α-(aminoxy)carboxylic acids. Upon visible-light irradiation, catalytically generated diboron enediolates undergo photoexcitation and energy transfer to O-sulfonylhydroxylamines, causing a novel SO bond cleavage pathway. This reactivity of the O-sulfonylhydroxylamine contrasts sharply with the conventional NO bond cleavage typically induced by single-electron reduction. The resulting N-oxyl radicals exhibit high reactivity, enabling the synthesis of sterically congested N-alkyl-α,α-disubstituted-α-(aminoxy)carboxylic acids. The protocol is applicable to the aminoxylation of pharmaceutical carboxylic acids. Beyond simple N-protected aminoxylating agents, α-amino acid-derived variants are also applicable, allowing for the construction of di- and tripeptides. Furthermore, leveraging the direct use of carboxylic acids, sequential condensation with glycine methyl ester enabled straightforward peptide elongation.

The CAAC-stabilized dithiolene (L⁰) zwitterion (1), an unusual redox-active intramolecular frustrated Lewis pair (FLP), activates the B─H bond of boranes via hydride-coupled reverse electron transfer processes. The reactions of 1 with catecholborane in THF give a zwitterionic bis(dithiolene)-based spiroborate (2), in which one sulphur atom (at the C2 carbon) bonds to the (CH₂)₄OB(O)₂C₆H₄ chain due to the catecholborane (CatBH)/S_thiourea Lewis pair-mediated THF ring opening. In addition to 2, [CAAC(H)]⁺[(Cat)₂B]⁻, (3), CAAC(H)₂, (4), and [CAAC(H)₃]⁺[(Cat)₂B]⁻, (5), are also isolated from these reactions. In addition to synthetic, structural, and spectroscopic data, a plausible reaction mechanism is proposed. This finding provides compelling experimental evidence of FLP-mediated B─H activation via net proton transfer.

An unprecedented gold(I)-catalyzed domino cyclization involving 2-ethynylbenzyl alcohol derivatives and heterocyclic α,β-unsaturated imines affords elaborated trispirocyclic cyclohexanes. This operationally simple protocol allows the one-pot generation of five bonds, three cycles, and four stereocentres in a short amount of time. Twenty substrates are successfully engaged, affording the desired products with good diastereoselectivity. The formation of these trispirocyclic compounds over other possible products has been rationalized by (DFT) density functional theory calculations.

Incorporating the SF₅ group into organic molecules is a powerful strategy for pushing the boundaries of chemistry and driving progress in drug discovery. In this context,a synthetic route to backbone-connected pentafluorosulfanyl β-amino esters is reported, which combine the unique physicochemical properties of the SF₅ group with those of β-amino acids. The approach begins with the preparation of an unprecedented library of (E)-α-SF₅-α,β-unsaturated esters via aldol condensation of SF₅ acetates with aldehydes. These SF₅-substituted Michael acceptors undergoes N-nucleophilic attack at the β-carbon under mild, practical conditions, affording a diverse array of α-SF₅-β^2,3-amino esters. The reactions deliver excellent yields and high diastereoselectivity, generating syn adducts with two contiguous stereogenic centers.

Silylium ions, three-coordinated as well as donor-stabilized, have attracted the interest of chemists for many years, have paved its way into practical application as catalysts for organic reactions, and have contributed to the understanding of fundamental chemistry problems. Since the first carbenes have been isolated and characterized, they had and still have an ongoing enormous impact on organic as well as on inorganic and organometallic chemistry. Herein, the synthesis and complete characterization of silatranyl cations as their acetonitrile- respectively propionitrile-coordinated hexachlorido antimonates is reported. Upon interaction of the former with 4-dimethylaminopyridine (DMAP) conversion to an unprecedented carbene–type complex of antimony pentachloride occurred, nicely combining silylium and carbene chemistry.

To harness the potential of rotary molecular systems (RMSs), it is basic to operate beyond thermodynamic equilibrium, requiring a continuous energy input. Light, due to its abundance, noninvasive nature, and precise spatial and temporal control, serves as an ideal energy source. This review highlights recent advances in bioinspired light-driven RMSs, with a particular focus on strategies to shift their activation wavelengths from UV to the visible and near-infrared regions through tailored structural modifications. A range of photochemical mechanisms underlying these systems, from reversible switching to unidirectional rotation, including emerging hybrid mechanisms that integrate multiple photophysical and/or chemical processes to achieve complex multistates behavior is discussed. Furthermore, it is explored that how specific molecular designs impact key photo-efficiency such as quantum yield and photostationary state distribution. These insights offer guiding principles to enhance the efficiency and functionality of RMSs and pave the way toward their integration in biomedical technologies requiring light-responsive control, such as targeted drug delivery and advanced imaging systems.

Amphirionin-5, derived from dinoflagellates of the genus Amphidinium, exhibits a unique biological activity whereby trace amounts can lead to potent proliferation of osteoblasts, making it a promising candidate for regenerative therapy of bone and treatment of osteoporosis. However, the relative configuration of amphirionin-5 has only been partially determined. Herein, the total synthesis of amphirionin-5 is undertaken to establish its overall stereochemistry. Synthesized C16-C28 model with the proposed relative configuration of C19-C23 shows significant discrepancies between its NMR spectroscopic data around C19 and those of the corresponding substructures of the natural amphirionin-5, suggesting of necessity for reconsideration of the relative configuration of C19. Two further 19S-type C11-C28 models are synthesized, and detailed NMR analysis reveals that the ¹³C NMR of (19S,26R)-C11-C28 models show the best agreement with those in the corresponding substructure of the natural product; thus, the relative configurations from C19 to C26 of amphirionin-5 are proposed as 19S*, 20S*, 23S*, and 26R*. Coupling of the C1-C16 segment, synthesized from an optically active α-silyloxy pentanolide as a common intermediate, and the (19S,26R)-C17-C28 segment is achieved under intermolecular Stetter reaction conditions, enabling the convergent total synthesis of the candidate diastereomer of amphirionin-5. Ultimately, the overall stereochemistry of amphirionin-5 is fully assigned.

Chalcogenide perovskites are an intriguing candidate for stable and nontoxic semiconductor devices, including multijunction photovoltaics. Experimental evidence that these materials can be made with high optoelectronic quality has often eluded researchers but has finally been shown in a recent publication by the Dimitrievska group. These findings motivate further efforts to develop of the first chalcogenide perovskite solar cells and better understand defect chemistry in these materials.