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High-valent metal-oxo species, such as iron(IV)-oxo porphyrin π-cation radical, are known to be involved in a variety of oxidative CH bond activation by metal complexes in the presence of oxidants. Although spectroscopic observations of these high-valent metal-oxo species are important for understanding reaction mechanisms, their high reactivities sometimes hamper direct observations, especially at ambient temperature. Herein, a high-valent iron-oxo species, involved in catalytic CH₄ oxidation by a µ-nitrido-bridged iron phthalocyanine dimer in an aqueous solution in the presence of excess H₂O₂, was successfully investigated by X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS), Raman, and matrix-assisted laser desorption and ionization-time-of-flight mass spectroscopy (MALDI-TOF MS) studies after deposition on a highly oriented pyrolytic graphite (HOPG) surface at room temperature. XPS study indicated the formation of a species with high oxidation states after treatment of the µ-nitrido-bridged iron phthalocyanine dimer attached on a HOPG with H₂O₂. Raman and O K-edge XAS studies, in combination with MALDI-TOF MS results, indicated the evidence for the formation of a species containing an oxygen atom with a double-bond character.

High-valent metal-oxo species, such as iron(IV)-oxo porphyrin π-cation radical, are known to be involved in a variety of oxidative CH bond activation by metal complexes in the presence of oxidants. Although spectroscopic observations of these high-valent metal-oxo species are important for understanding reaction mechanisms, their high reactivities sometimes hamper direct observations, especially at ambient temperature. Herein, a high-valent iron-oxo species, involved in catalytic CH₄ oxidation by a µ-nitrido-bridged iron phthalocyanine dimer in an aqueous solution in the presence of excess H₂O₂, was successfully investigated by X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS), Raman, and matrix-assisted laser desorption and ionization-time-of-flight mass spectroscopy (MALDI-TOF MS) studies after deposition on a highly oriented pyrolytic graphite (HOPG) surface at room temperature. XPS study indicated the formation of a species with high oxidation states after treatment of the µ-nitrido-bridged iron phthalocyanine dimer attached on a HOPG with H₂O₂. Raman and O K-edge XAS studies, in combination with MALDI-TOF MS results, indicated the evidence for the formation of a species containing an oxygen atom with a double-bond character.

The synthesis and characterization of the stibanyltrielanes IDipp·GaH₂Sb(SiMe₃)₂ (1a) and IDipp·BH₂Sb(SiMe₃)₂ (1b) are presented. 1a represents the first example for the isolation of a molecular stibanylgallane monomer stabilized only by a Lewis base (LB). While methanolytic cleavage of the {SiMe₃} residues in 1a cannot be achieved, the direct salt metathesis reactions of K(18c6)SbH₂ with LB·EH₂X (LB = IDipp, NMe₃; E = B, Ga; X = I, OTf) afford the isolation of the parent compounds IDipp·BH₂SbH₂ (2a), Me₃N·BH₂SbH₂ (2b), and IDipp·GaH₂SbH₂ (3) for the first time in moderate yields. Specifically, the synthesis of 3 not only represents the first stabilization of the {GaH₂SbH₂} motif as the so far heaviest known ethylene-like parent group 13/15 element combination but also validates its stabilization procedure by a LB to access a first sterically unhindered primary stibane. All compounds display drastic sensitivity toward air, light, and temperature. The products are characterized by NMR and infrared spectroscopy, as well as by single-crystal X-ray structure determination and mass spectrometry and the electronic structure is investigated by density functional theory calculations. Furthermore, the reaction of IDipp·GaCl₃ with K(18c6)SbH₂ yields a product mixture, in which 3 and the unprecedented IDipp·GaH(SbH₂)₂ (4) can be identified.

The synthesis and characterization of the stibanyltrielanes IDipp·GaH₂Sb(SiMe₃)₂ (1a) and IDipp·BH₂Sb(SiMe₃)₂ (1b) are presented. 1a represents the first example for the isolation of a molecular stibanylgallane monomer stabilized only by a Lewis base (LB). While methanolytic cleavage of the {SiMe₃} residues in 1a cannot be achieved, the direct salt metathesis reactions of K(18c6)SbH₂ with LB·EH₂X (LB = IDipp, NMe₃; E = B, Ga; X = I, OTf) afford the isolation of the parent compounds IDipp·BH₂SbH₂ (2a), Me₃N·BH₂SbH₂ (2b), and IDipp·GaH₂SbH₂ (3) for the first time in moderate yields. Specifically, the synthesis of 3 not only represents the first stabilization of the {GaH₂SbH₂} motif as the so far heaviest known ethylene-like parent group 13/15 element combination but also validates its stabilization procedure by a LB to access a first sterically unhindered primary stibane. All compounds display drastic sensitivity toward air, light, and temperature. The products are characterized by NMR and infrared spectroscopy, as well as by single-crystal X-ray structure determination and mass spectrometry and the electronic structure is investigated by density functional theory calculations. Furthermore, the reaction of IDipp·GaCl₃ with K(18c6)SbH₂ yields a product mixture, in which 3 and the unprecedented IDipp·GaH(SbH₂)₂ (4) can be identified.

The rational synthesis of metal–organic frameworks (MOFs) plays a critical role in studying the correlation between their structure and properties. Among various synthesis strategies, electrosynthesis has emerged as a promising approach for the rapid and controllable preparation of various MOFs. Herein, a novel MOF single crystal featuring the porphyrin block and the coordinated linkage between pyridine and cadmium (Cd²⁺) ions is electrolytically synthesized as millimeter-sized single crystal under mild ambient condition. Temperature-dependent changes in its 3D cross-interpenetrating topology are systematically investigated. Moreover, the as-synthesized MOF single crystal exhibits typical semiconductive behavior with a narrow bandgap of 1.12 eV. This study exploits the potential of electrosynthesis as a clean and scalable approach to address the synthesis of MOF single crystal.

Lithium metal batteries (LMBs) with high-voltage high-Ni cathodes (LiNi_xCo_yMn_zO₂, x ≥ 0.8) are highly promising for next-generation high-energy-density storage systems. However, the combination of reactive Li anodes, ultrahigh-Ni-content cathodes (NCM90, x ≥ 0.9), and elevated charging voltages leads to severe interfacial side reactions, capacity degradation, and safety hazards, necessitating functional electrolytes for mitigation. This work introduces a dual-additive strategy using bis(trifluoromethanesulfonyl)imide (TFSI⁻) and bis(oxalato)borate (BOB⁻) anions to regulate electrolyte solvation structure and enhance electrode–electrolyte interphase (EEI) stability. Theoretical simulations and experimental results demonstrate that the modified electrolytes form anion-rich solvation sheaths, which preferentially decompose to create thin and robust EEIs rich in inorganic components. These EEIs effectively suppress electrolyte oxidation and transition metal dissolution on NCM90 cathodes while promoting uniform Li deposition with a high Coulombic efficiency (≈99%) on anodes. Consequently, Li||NCM90 batteries exhibit superior electrochemical performance under 4.6 V operation, including 84.8% capacity retention after 200 cycles at 1C and a reversible capacity of 153.8 mAh g⁻¹ at 5C. This dual-anion approach offers critical insights into EEI engineering via solvation chemistry tailoring, providing a viable pathway for developing stable high-voltage high-Ni LMBs.

Active learning (AL) can significantly accelerate drug discovery by iteratively selecting informative molecules, reducing experimental workload. However, existing AL studies typically assume access to large datasets, an unrealistic scenario for most academic labs. AL strategies tailored specifically for small-scale molecular screening, are investigated, using only 110 affinity evaluations approximated by docking scores from realistic compound libraries: the Developmental Therapeutics Program repository (DTP) and Enamine Discovery Diversity Set 10 (DDS-10). Among 20 tested combinations of molecular descriptors and machine learning models, continuous and data-driven descriptors combined with a multilayer perceptron, augmented by the pairwise difference regression data augmentation technique, are identified as optimal. This combination achieves a 100% probability of discovering at least five top-1% hits from DTP using only 110 affinity evaluations which remains high under simulated experimental uncertainty. Similarly, the DDS-10 dataset achieves a 100% probability of discovering at least five top-1% hits. Incorporating prior knowledge by enriching initial datasets with a single known hit molecule increased the probability of finding 20 or more hits. These findings underscore the feasibility and substantial potential of AL for small-scale drug discovery in resource-limited environments. These results suggest that early in the AL search the algorithm benefits from accurately quantifying the binding strengths of very weak binders.

The development of aqueous organic redox-flow batteries (AORFB) requires finding new posolyte alternatives to the ferrocyanide salts used presently. Among the potential families, phenothiazine has been reported to be of interest if its solubility in aqueous medium is successfully increased. In this article, the phenothiazine propyl sulfonate (PTZPS) is evaluated as a promising high-potential posolyte for neutral-medium aqueous redox-flow battery. It is demonstrated that electrochemical reversibility is highly dependent on pH, with namely a fast capacity loss in neutral medium. Through the preparation of the oxidized form of this molecule, a kinetic study is performed, confirming the crucial role of the electron transfer step between two molecules at this redox state. Even if density functional theory (DFT) calculations of the electron transfer are not successful due to the significant multireference character of the oxidized form's dyad, using MD simulations, the behavior of the oxidized form in various media is qualitatively predicted, including the effect of addition of chaotropic additives.

Porous silicon nanoparticles (pSiNPs) represent a unique drug delivery candidate owing to the biocompatibility, degradability, high loading capacity, and production scalability. Various endeavors have been reported to make practical formulations with pSiNPs. However, existing protocols still lack simplicity and sometimes stability in physiological environment. Herein, the use of stimuli-responsive poly(disulfide)s as a sealing/coating strategy for pSiNPs is reported. The polymer matrix is formed in one-pot protocols in water, and various payloads, including small molecule drugs, drug conjugate, and small interfering RNA (siRNA), are loaded spontaneously. The engineered hybrid nanoparticles demonstrated excellent stability in saline and tunable degradability. Drugs like doxorubicin (DOX) and camptothecin (CPT) are loaded physically by polymer entrapment, with loading efficiencies (LE) of 25% and 97%, and payload-silicon ratios (P/Si) of 54% and 97%, respectively. A disulfide-based self-immolative linker (SIL) is also used to covalently load CPT (LE 93%, P/Si 12%). To load siRNA, a polymerizable ionizable lipid (PIL) strategy is developed. siRNA is loaded via electrostatic interactions followed by polymer entrapment (LE 36%, P/Si 14.4%). In vitro experiments reveal the successful delivery of therapeutic candidates in cells. These combined efforts provide a practical solution for the use of pSiNPs in drug delivery.

The development of aqueous organic redox-flow batteries (AORFB) requires finding new posolyte alternatives to the ferrocyanide salts used presently. Among the potential families, phenothiazine has been reported to be of interest if its solubility in aqueous medium is successfully increased. In this article, the phenothiazine propyl sulfonate (PTZPS) is evaluated as a promising high-potential posolyte for neutral-medium aqueous redox-flow battery. It is demonstrated that electrochemical reversibility is highly dependent on pH, with namely a fast capacity loss in neutral medium. Through the preparation of the oxidized form of this molecule, a kinetic study is performed, confirming the crucial role of the electron transfer step between two molecules at this redox state. Even if density functional theory (DFT) calculations of the electron transfer are not successful due to the significant multireference character of the oxidized form's dyad, using MD simulations, the behavior of the oxidized form in various media is qualitatively predicted, including the effect of addition of chaotropic additives.