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Ru is extensively used in electrical and energy applications because of its high electrical conductivity and catalytic activity. This study reports the H2 plasma-enhanced atomic layer deposition (PEALD) of Ru thin films using a novel carbonyl cyclohexadiene ruthenium precursor. The optimized process conditions for depositing Ru thin films by PEALD were established based on the growth per cycle (GPC), chemical formation, crystallinity, conformality, and resistivity, according to process parameters such as precursor pulse time, H2 plasma pulse time, purge time, and deposition temperature. Pure Ru thin films (low carbon and oxygen) were deposited with low resistivity (30.8 μΩ cm) and showed high conformality (> 95%) on the Si trenches. The oxidant-free PEALD Ru process reported in this study may have implications on the fabrication of high-quality interfaces between Ru and easily-oxidized substrates. [ABSTRACT FROM AUTHOR]

Ru(BINAP)(PPh3)HCl cleanly reacts with LiCH2TMS to give Ru(BINAP)(PPh3) (1) that has been fully characterized, including by X‐ray diffraction (BINAP and TMS stand for (2,2′‐bis(diphenylphosphino)‐1,1′‐binaphthyl and trimethylsilyl respectively). In sharp contrast with other carbonyl‐free phosphine complexes of Ru(0), 1 demonstrates a strikingly high thermal stability and no propensity for intramolecular C−H activation (cyclometalation). Yet 1 coordinates acetonitrile and readily exchanges its PPh3 ligand with alkenes and dienes, thus behaving like a "masked" 16‐e Ru(0) species. Electron‐poor alkenes coordinate more readily than electron‐rich ones, which testifies for the nucleophilic character of the Ru(0)‐BINAP fragment. While being thermally stable, 1 is highly reactive and is capable of activating C−H and N−H bonds, and even of cleaving an inert N−Et bond. The combination of high reactivity and stability originates from the P,arene‐chelation by the BINAP ligand, i.e., the coordinated π‐arene stabilizes Ru(0) to prevent cyclometalation, yet it can slide upon substrate coordination, thereby enabling a variety of inert bond activation reactions to occur under mild conditions. [ABSTRACT FROM AUTHOR]

Ru(BINAP)(PPh3)HCl cleanly reacts with LiCH2TMS to give Ru(BINAP)(PPh3) (1) that has been fully characterized, including by X‐ray diffraction (BINAP and TMS stand for (2,2′‐bis(diphenylphosphino)‐1,1′‐binaphthyl and trimethylsilyl respectively). In sharp contrast with other carbonyl‐free phosphine complexes of Ru(0), 1 demonstrates a strikingly high thermal stability and no propensity for intramolecular C−H activation (cyclometalation). Yet 1 coordinates acetonitrile and readily exchanges its PPh3 ligand with alkenes and dienes, thus behaving like a "masked" 16‐e Ru(0) species. Electron‐poor alkenes coordinate more readily than electron‐rich ones, which testifies for the nucleophilic character of the Ru(0)‐BINAP fragment. While being thermally stable, 1 is highly reactive and is capable of activating C−H and N−H bonds, and even of cleaving an inert N−Et bond. The combination of high reactivity and stability originates from the P,arene‐chelation by the BINAP ligand, i.e., the coordinated π‐arene stabilizes Ru(0) to prevent cyclometalation, yet it can slide upon substrate coordination, thereby enabling a variety of inert bond activation reactions to occur under mild conditions. [ABSTRACT FROM AUTHOR]

The paper describes an investigation into hydrogenation of furfural over ruthenium catalysts supported on porous aromatic frameworks. The supports were designated as PAF-30-SO3H, PAF-30-NH2, and PAF-30. The synthesized catalysts were tested in furfural hydrogenation carried out in water and in tetrahydrofuran (with a concentration of 10 wt %) at 90–250°C and a hydrogen pressure of 3 MPa. Although the highest furfural conversion (96%) was achieved in the case of its hydrogenation in water at 250°C over Ru-PAF-30, these conditions did not favor product selectivity. The reaction products mainly consisted of furfuryl alcohol, tetrahydrofurfuryl alcohol, and cyclopentanone. The highest yield of cyclopentanone, 71% (with 80% conversion and 89% selectivity) was observed in furfural hydrogenation over Ru-PAF-30 at 200°C, whereas the conditions optimal for selective hydrogenation of furfural into furfuryl alcohol were found to include either tetrahydrofuran as a solvent or water as a solvent and low temperatures (90–150°C). [ABSTRACT FROM AUTHOR]

Mesoporous materials have found wide application as catalyst supports. In this study, we have shown that Ru nanoparticles supported on SBA-15 are highly active toward hydrogenation of biomass-derived ethyl levulinate (EL) even at room temperature. A series of Ru loaded SBA-15 (xRu-SBA-15, x = 1, 3, and 5 wt% Ru) were prepared by a deposition-precipitation method and further reduced with NaBH4. TEM images suggest that the reduction with NaBH4 led to the formation of Ru particle with size in range of 1–2 nm. These finely distributed Ru nanoparticles on SBA-15 showed high activity for hydrogenation of C=O group of EL at room temperature and a low H2 pressure (0.5 MPa), with ethyl hydroxylpentanonate (EHP) selectivity of 97%. Kinetics study showed that the Ru nanoparticles in proper size (2.1 ± 0.1 nm) gave a low apparent activation energy (Ea) about 20 kJ/mol for C=O hydrogenation. Moreover, 3Ru-SBA-15 displayed a good reusability, on which the EL conversion remained stable (− 80%) after five recycles. The produced EHP could be further converted to γ-valerolactone (GVL) over HZMS-5 efficiently upon thermal treatment. [ABSTRACT FROM AUTHOR]

The Ru-V 8 C 7 /C electrocatalyst has been synthesized by anchoring Ru nanoparticles on the porous V 8 C 7 /C matrix via pyrolysis of metal organic-frameworks V-BDC (BDC: 1,4-benzenedicarboxylate), exhibiting excellent HER performance in all pH ranges, especially the high mass activities and long-term stability under neutral conditions. [Display omitted] The development of cost-effective electrocatalysts with high efficiency and long durability for hydrogen evolution reaction (HER) remains a great challenge in the field of water splitting. Herein, we design an ultrafine and highly dispersed Ru nanoparticles stabilized on porous V 8 C 7 /C matrix via pyrolysis of the metal–organic frameworks V-BDC (BDC: 1,4-benzenedicarboxylate). The obtained Ru-V 8 C 7 /C composite exhibits excellent HER performance in all pH ranges. At the overpotential of 40 mV, its mass activity is about 1.9, 4.1 and 9.4 times higher than that of commercial Pt/C in acidic, neutral and alkaline media, respectively. Meanwhile, Ru-V 8 C 7 /C shows the remarkably high stability in all pH ranges which, in particular, can maintain the current density of 10 mA cm−2 for over 150 h in 1.0 mol L−1 phosphate buffer saline (PBS). This outstanding HER performance can be attributed to the high intrinsic activity of Ru species and their strong interface interactions to the V 8 C 7 /C substrate. The synergistic effect of abundant active sites on the surface and the formed Ru–C–V units at the interface promotes the adsorption of reaction intermediates and the release of active sites, contributing the fast HER kinetics. This work provides a reference for developing versatile and robust HER catalysts by surface and interface regulation for pH tolerance. [ABSTRACT FROM AUTHOR]

Nanostructured ionic compounds have driven major technological advancements in displays, photovoltaics, and catalysis. Current research focuses on refining the chemical composition of such compounds. In this study, a strategy for creating stoichiometrically well‐defined nanoscale multiple‐cation systems, where the atomically precise structure maximizes the synergistic cooperation between cations at the atomic scale is reported. The unprecedented construction of Heusler‐type PtRuP2 double‐walled nanotubes through sequential anion/cation exchange reactions is demonstrated. The PtRuP2 catalyst exhibits record‐high catalytic performance and durability for the hydrogen evolution reaction (HER) in alkaline electrolytes and anion‐exchange membrane water electrolyzers. The investigations highlight the crucial role of Pt/Ru dual centers, providing multiple active sites that accelerate the HER kinetics within a single phosphide material, in the sequential operation of H2O activation/dissociation at Ru and H2 production at adjacent Pt sites. These findings open new avenues for optimizing ionic compound‐based HER electrocatalysts, offering platinum‐metal alternatives in acidic and alkaline media. [ABSTRACT FROM AUTHOR]

The grooves of DNA provide recognition sites for many nucleic acid binding proteins and anticancer drugs such as the covalently binding cisplatin. Here we report a crystal structure showing, for the first time, groove selectivity by an intercalating ruthenium complex. The complex Λ‐[Ru(phen)2phi]2+, where phi=9,10‐phenanthrenediimine, is bound to the DNA decamer duplex d(CCGGTACCGG)2. The structure shows that the metal complex is symmetrically bound in the major groove at the central TA/TA step, and asymmetrically bound in the minor groove at the adjacent GG/CC steps. A third type of binding links the strands, in which each terminal cytosine base stacks with one phen ligand. The overall binding stoichiometry is four Ru complexes per duplex. Complementary biophysical measurements confirm the binding preference for the Λ‐enantiomer and show a high affinity for TA/TA steps and, more generally, TA‐rich sequences. A striking enantiospecific elevation of melting temperatures is found for oligonucleotides which include the TATA box sequence. [ABSTRACT FROM AUTHOR]

The grooves of DNA provide recognition sites for many nucleic acid binding proteins and anticancer drugs such as the covalently binding cisplatin. Here we report a crystal structure showing, for the first time, groove selectivity by an intercalating ruthenium complex. The complex Λ‐[Ru(phen)2phi]2+, where phi=9,10‐phenanthrenediimine, is bound to the DNA decamer duplex d(CCGGTACCGG)2. The structure shows that the metal complex is symmetrically bound in the major groove at the central TA/TA step, and asymmetrically bound in the minor groove at the adjacent GG/CC steps. A third type of binding links the strands, in which each terminal cytosine base stacks with one phen ligand. The overall binding stoichiometry is four Ru complexes per duplex. Complementary biophysical measurements confirm the binding preference for the Λ‐enantiomer and show a high affinity for TA/TA steps and, more generally, TA‐rich sequences. A striking enantiospecific elevation of melting temperatures is found for oligonucleotides which include the TATA box sequence. [ABSTRACT FROM AUTHOR]

The grooves of DNA provide recognition sites for many nucleic acid binding proteins and anticancer drugs such as the covalently binding cisplatin. Here we report a crystal structure showing, for the first time, groove selectivity by an intercalating ruthenium complex. The complex Λ‐[Ru(phen)2phi]2+, where phi=9,10‐phenanthrenediimine, is bound to the DNA decamer duplex d(CCGGTACCGG)2. The structure shows that the metal complex is symmetrically bound in the major groove at the central TA/TA step, and asymmetrically bound in the minor groove at the adjacent GG/CC steps. A third type of binding links the strands, in which each terminal cytosine base stacks with one phen ligand. The overall binding stoichiometry is four Ru complexes per duplex. Complementary biophysical measurements confirm the binding preference for the Λ‐enantiomer and show a high affinity for TA/TA steps and, more generally, TA‐rich sequences. A striking enantiospecific elevation of melting temperatures is found for oligonucleotides which include the TATA box sequence. [ABSTRACT FROM AUTHOR]

The grooves of DNA provide recognition sites for many nucleic acid binding proteins and anticancer drugs such as the covalently binding cisplatin. Here we report a crystal structure showing, for the first time, groove selectivity by an intercalating ruthenium complex. The complex Λ‐[Ru(phen)2phi]2+, where phi=9,10‐phenanthrenediimine, is bound to the DNA decamer duplex d(CCGGTACCGG)2. The structure shows that the metal complex is symmetrically bound in the major groove at the central TA/TA step, and asymmetrically bound in the minor groove at the adjacent GG/CC steps. A third type of binding links the strands, in which each terminal cytosine base stacks with one phen ligand. The overall binding stoichiometry is four Ru complexes per duplex. Complementary biophysical measurements confirm the binding preference for the Λ‐enantiomer and show a high affinity for TA/TA steps and, more generally, TA‐rich sequences. A striking enantiospecific elevation of melting temperatures is found for oligonucleotides which include the TATA box sequence. [ABSTRACT FROM AUTHOR]

Catalytic hydrogenolysis has the potential to convert high‐density polyethylene (HDPE), which comprises about 30 % of plastic waste, into valuable alkanes. Most investigations have focused on increasing activity for lab grade HDPEs displaying low molecular weight, with limited mechanistic understanding of the product distribution. No efficient catalyst is available for consumer grades due to their lower reactivity. This study targets HDPE used in bottle caps, a waste form generated globally at a rate of approximately one million units per hour. Ultrafine ruthenium particles (1 nm) supported on titania (anatase) achieved up to 80 % conversion into light alkanes (C1−C45) under mild conditions (498 K, 20 bar H2, 4 h) and were reused for three cycles. Small ruthenium nanoparticles were critical to achieving relevant conversions, as activity sharply decreased with particle size. Selectivity commonalities and peculiarities across HDPE grades were disclosed by a reaction modelling approach applied to products. Isomerization cedes to backbone scission as the reaction progresses. Within this trend, low molecular weight favor isomerization whilst high molecular weight favor cleavage. Commercial caps obeyed this trend with decreased activity, anticipating the influence of additives in realistic processing. This study demonstrates effective hydrogenolysis of consumer grade polyethylene and provides selectivity patterns for product control. [ABSTRACT FROM AUTHOR]

Biowaste-derived carbon materials are a sustainable, environmentally friendly, and cost-effective way to create valuable materials. Activated carbon can be a supporting material for electrocatalysts because of its large specific surface area and porosity. However, activated carbon has low catalytic activity and needs to be functionalized with heteroatoms, metals, and combinations to improve conductivity and catalytic activity. Ruthenium (Ru) catalysts have great potential to replace bench market catalysts in hydrogen evolution reaction (HER) applications due to their similar hydrogen bond strength and relatively lower price. This study reports on the synthesis and characterizations of carbon-supported Ru catalysts with large surface areas (~ 1171 m2 g−1) derived from coffee waste. The uniformly dispersed Ru nanoparticles on the porous carbon has excellent electrocatalytic activity and outperformed the commercial catalyst platinum on carbon (Pt/C) toward the HER. As-synthesized catalyst needed only 27 mV to reach a current density of 10 mA cm−2, 58.4 mV dec−1 Tafel slope, and excellent long-term stability. Considering these results, the Ru nanoparticles on coffee waste-derived porous carbon can be utilized as excellent material that can replace platinum-based catalysts for the HER and contribute to the development of eco-friendly and low-cost electrocatalyst materials. [ABSTRACT FROM AUTHOR]

There are few literature reports on using precatalysts based on ruthenium(II / III) ions in the polymerization of olefins. Therefore, a new coordination compound was designed based on ruthenium(III) ion and 2-phenylpyridine. The resulting monocrystal was characterized by X-ray diffraction (XRD), solid-state (photo)IR spectroscopy, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The new ruthenium(III) complex compound was used as a precatalyst in the oligomerization reactions of ethylene, 2-propen-1-ol, 2-chloro-2-propen-1-ol, 3-butene-2-ol and 2,3-dibromo-2-propen-1-ol with methylaluminoxane and ethylaluminium dichloride as activators. The catalytic activity of the newly discovered ruthenium(III) complex compound ranges from 159.5 (for 2-chloro-2-propen-1-ol) to 755.6 (for ethylene) g mmol−1 h−1 bar−1, indicating that it is a chemical compound with high catalytic activity. In addition, the oligomerization reaction products were subjected to physicochemical characterization, using BET (Brunauer–Emmett–Teller isotherm), mass spectrometry (MALDI-TOF-MS), Fourier transform infrared (FT-IR) spectroscopy, NMR, TGA, differential scanning calorimetry (DSC), and the morphology of the porous polymeric materials was investigated by SEM. The distinguishing feature of the obtained precatalyst is its high catalytic activity under mild reaction conditions, a rare phenomenon. Compared with other precatalysts, it is the most active ruthenium(II / III) ion-based catalytic material used in oligo- and polymerization reactions of ethylene. [ABSTRACT FROM AUTHOR]

The rational design of an efficient nanocatalyst is pivotal for catalyzing kinetically sluggish oxygen evolution reaction (OER). However, the uncontrolled nucleation and growth of nanostructures present significant challenges in the effectiveness and economic viability of implementing noble metal-based electrocatalysts. Functionalized metal–organic frameworks (MOFs) exhibit properties that can stabilize unstable nanoclusters in extremely small sizes by mitigating issues related to high surface energy and Ostwald's ripening effect. In this study, we present the synthesis of ultrasmall Ruthenium nanoclusters stabilized through a thiol-functionalized Ni-MOF (RuNC/Ni-M-SH). The stabilization of ruthenium under reduced conditions on the MOF surface is facilitated by the lower electronegativity and increased orbital overlapping effect of sulfur, resulting in an average size of 1.5 nm. X-ray photoelectron spectroscopy and X-ray absorption spectroscopy studies confirm a perturbed electronic structure, providing a fundamental understanding of electronic redistribution. With this favorable electronic structure, the catalytic OER activity of RuNC/Ni-M-SH surpasses that of the state-of-the-art RuO2, exhibiting a 3-fold increase in current density (242 mA cm–2) and a 82 mV reduced overpotential. Furthermore, in situ FTIR and Raman analyses were performed to analyze the catalytically active sites and intermediates. With 95% faradaic efficiency, the turnover frequency (TOF) and mass activity of RuNC/Ni-M-SH are several orders of magnitude higher than RuO2. Remarkably, unlike other Ru-based catalysts, RuNC/Ni-M-SH demonstrates exceptional high stability, as evidenced by over 24 h of chronoamperometry study. These attributes of RuNC/Ni-M-SH established it as an economically sustainable OER electrocatalyst. [ABSTRACT FROM AUTHOR]

Rising antimicrobial resistance (AMR) and lack of innovation in the antibiotic pipeline necessitate novel approaches to discovering new drugs. Metal complexes have proven to be promising antimicrobial compounds, but the number of studied compounds is still low compared to the millions of organic molecules investigated so far. Lately, machine learning (ML) has emerged as a valuable tool for guiding the design of small organic molecules, potentially even in low‐data scenarios. For the first time, we extend the application of ML to the discovery of metal‐based medicines. Utilising 288 modularly synthesized ruthenium arene Schiff‐base complexes and their antibacterial properties, a series of ML models were trained. The models perform well and are used to predict the activity of 54 new compounds. These displayed a 5.7x higher hit‐rate (53.7 %) against methicillin‐resistant Staphylococcus aureus (MRSA) compared to the original library (9.4 %), demonstrating that ML can be applied to improve the success‐rates in the search of new metalloantibiotics. This work paves the way for more ambitious applications of ML in the field of metal‐based drug discovery. [ABSTRACT FROM AUTHOR]

Ruthenium(II) complexes with chelating polypyridine ligands are among the most frequently investigated compounds in photophysics and photochemistry, owing to their favorable luminescence and photoredox properties. Equally good photoluminescence performance and attractive photocatalytic behavior is now achievable with isoelectronic molybdenum(0) complexes. The zero‐valent oxidation state of molybdenum is stabilized by carbonyl or isocyanide ligands, and metal‐to‐ligand charge transfer (MLCT) excited states analogous to those in ruthenium(II) complexes can be established. Microsecond MLCT excited‐state lifetimes and photoluminescence quantum yields up to 0.2 have been achieved in solution at room temperature, and the emission wavelength has become tunable over a large range. The molybdenum(0) complexes are stronger photoreductants than ruthenium(II) polypyridines and can therefore perform more challenging chemical reductions. The triplet nature of their luminescent MLCT states allows sensitization of photon upconversion via triplet‐triplet annihilation, to convert low‐energy input radiation into higher‐energy output fluorescence. This review summarizes the current state of the art concerning luminescent molybdenum(0) complexes and highlights their application potential. Molybdenum is roughly 140 times more abundant and far cheaper than ruthenium, hence this research is relevant in the greater context of finding more sustainable alternatives to using precious and rare transition metals in photophysics and photochemistry. [ABSTRACT FROM AUTHOR]

Die steigende antimikrobielle Resistenz (AMR) und der Mangel an Innovation in der Antibiotikaforschung erfordern neue Ansätze zur Entwicklung von Medikamenten. Metallkomplexe haben sich als vielversprechende antimikrobielle Verbindungen erwiesen. Allerdings ist die Anzahl der untersuchten Verbindungen noch klein, besonders im Vergleich zu den Millionen organischer Moleküle die bereits getestet wurden. In den letzten Jahren hat sich maschinelles Lernen (ML) als wertvolle Ressource für die Entwicklung organischer Moleküle herauskristallisiert, selbst wenn nur wenige Daten vorliegen. Erstmals erweitern wir die Anwendung von ML auf die Entdeckung von metallbasierten antimikrobiellen Verbindungen. Mithilfe von 288 modular synthetisierten Ruthenium‐Aren‐Schiff‐Basen‐Komplexen und deren antibakteriellen Eigenschaften haben wir eine Reihe von ML–Modellen trainiert. Die Modelle zeigen gute Leistungen und werden verwendet, um die Aktivität von 54 neuen Verbindungen vorherzusagen. Diese Verbindungen weisen eine 5.7‐fach höhere Trefferquote (53.7 %) gegen Methicillin‐resistente Staphylococcus aureus (MRSA) im Vergleich zur ursprünglichen Bibliothek (9.4 %) auf. Dadurch zeigen wir, dass ML zu höheren Erfolgsraten bei der Suche nach neuen Metalloantibiotika führen kann. Folglich ebnet diese Arbeit den Weg für fortschrittlichere Anwendungen von ML im Bereich der metallbasierten Wirkstoffentwicklung. [ABSTRACT FROM AUTHOR]

The compound cis-diamminedichloroplatinum(II) (cisplatin) is the most widely used anticancer drug, but due to its serious side effects (including gastrointestinal symptoms, renal tubular injury, neuromuscular complications, and ototoxicity), clinical applications of cisplatin are limited. Therefore, these limitations have provided an encouragement for further research into other transition metal complexes, with an aim to overcome the disadvantages related with cisplatin therapy. In the search for effective complexes that can be targeted against tumor cells, many research groups synthesized various ruthenium(II) complexes with different ligands. Also, newly synthesized ruthenium(II) complexes showed selective anticancer activity against different types of cancer cells. Activity of ruthenium(II) complexes in some cases was even higher than that of cisplatin against the same cells. Precise mechanism of action of ruthenium(II) complexes is not fully understood. The different examples mentioned in this review showed that ruthenium(II) complexes decreased viability of cancer cells by induction of apoptosis and/or by cell cycle arrest which implies their different mechanism of action against different types of cancer cells. [ABSTRACT FROM AUTHOR]

In this study, dinuclear and tetranuclear arene ruthenium porphyrins were synthesized and assessed for their potential as photosensitizers (PSs) in photodynamic therapy (PDT) using the Colo205 colon cancer cell line as a model system. Reactive oxygen species (ROS) production, cellular uptake, impact on cell viability, and mechanisms of cell death induced by the synthesized compounds were comprehensively investigated. Our results revealed that the number of arene ruthenium units, as well as zinc (Zn) metalation of the porphyrin core, significantly influenced ROS production and increased it two-folds compared to the Zn-free analogs. The uptake of tetra-substituted Zn-porphyrins by the cancer cells increased to 2.8 nmol/106 cells compared to 0.6 nmol/106 cells of the disubstituted Zn-free and Zn-chelating porphyrins. The anticancer photo-activity of the complexes, where the percentage of metabolic activity of disubstituted Zn-porphyrins decreased to 26% when Zn was inserted, was compared to disubstituted Zn-free analogs. A further decrease in metabolic activity was observed, when the number of arene ruthenium units increased in the tetra-substituted Zn-porphyrins and tetra-substituted Zn-free compounds, reaching 4% and 14% respectively. Moreover, the percentage of apoptotic cell deaths increased to 40% when Zn was inserted into disubstituted porphyrins, compared to disubstituted Zn-free analog, and 50% when the number of arene ruthenium units increased. Overall, the tetra-substituted Zn chelating porphyrins exhibited the highest PDT efficiency, followed by the di-substituted Zn-porphyrins. These findings underscore the importance of structural design in optimizing the efficacy of arene ruthenium porphyrins as PSs for PDT, offering valuable insights for the development of targeted cancer therapeutics. [ABSTRACT FROM AUTHOR]

Organometallic η6-arene ruthenium(II) complexes with 3-chloro-6-(1H-pyrazol-1-yl)pyridazine (Ru1, Ru2, and Ru5) and 3-chloro-6-(3,5-dimethyl-1H-pyrazol-1-yl)pyridazine (Ru3-4) N,N' heterocyclic and η6-arene (cymene (Ru1-4) or toluene (Ru 5)) have been synthesized. The ruthenium(II) complexes have common "three-legged piano-stool" pseudo-octahedral structures known for half-sandwich complexes. Evolution of their UV–Visible absorption spectra in PBS buffer or DMSO over 24 h confirmed their good solvolysis stability. Titrations of the complexes with the calf thymus DNA (CT-DNA) were monitored using UV–Visible absorption and fluorescence spectroscopies. The complexes interact moderately with CT-DNA and their binding constants are in the order of 104 M−1. Competitive binding of the complexes to a DNA-Hoechst 33,258 depicted competitive displacement of Hoechst from DNA's minor grooves. These complexes bind to glutathione forming GSH-adducts through S coordination by replacement of a halide, with the iodo-analogues having higher binding constants than the chloro-complexes. Cyclic voltammograms of the complexes exhibited one electron-transfer quasi-reversible process. Trends in the molecular docking data of Ru1-5/DNA were similar to those for DNA binding constants. Of the five, only Ru1, Ru3 and Ru5 showed some activity (moderate) against the MCF-7 breast cancer cells with IC50 values in the range of 59.2–39.9 for which Ru5 was the most active. However, the more difficult-to-treat cell line, MDA-MB 231 cell was recalcitrant to the treatment by these complexes. Molecular docking simulations visualized the interactions of arene Ru(II) complexes with CT-DNA via minor grooving. The trends were corroborated by electrochemical and cytotoxicity data. [ABSTRACT FROM AUTHOR]

Transition metal complexes with characteristics of unique packaging in nanoparticles and remarkable cancer cell cytotoxicity have emerged as potential alternatives to platinum-based antitumor drugs. Here we report the synthesis, characterization, and antitumor activities of three new Ruthenium complexes that introduce 5-fluorouracil-derived ligands. Notably, encapsulation of one such metal complex, Ru3, within pluronic® F-127 micelles (Ru3-M) significantly enhanced Ru3 cytotoxicity toward A549 cells by a factor of four. To determine the mechanisms underlying Ru3-M cytotoxicity, additional in vitro experiments were conducted that revealed A549 cell treatment with lysosome-targeting Ru3-M triggered oxidative stress, induced mitochondrial membrane potential depolarization, and drastically reduced intracellular ATP levels. Taken together, these results demonstrated that Ru3-M killed cells mainly via a non-apoptotic pathway known as oncosis, as evidenced by observed Ru3-M-induced cellular morphological changes including cytosolic flushing, cell swelling, and cytoplasmic vacuolation. In turn, these changes together caused cytoskeletal collapse and activation of porimin and calpain1 proteins with known oncotic functions that distinguished this oncotic process from other cell death processes. In summary, Ru3-M is a potential anticancer agent that kills A549 cells via a novel mechanism involving Ru(II) complex triggering of cell death via oncosis. [ABSTRACT FROM AUTHOR]

Colloidal Ru nanoparticles (NP) display interesting catalytic properties for the hydrogenation of (hetero)arenes as they proceed efficiently in mild reaction conditions. In this work, a series of Ru based materials was used in order to selectively hydrogenate quinaldine and assess the impact of the stabilizing agent on their catalytic performances. Ru nanoparticles stabilized with polyvinylpyrrolidone (PVP) and 1‐adamantanecarboxylic acid (AdCOOH) allowed to obtain 5,6,7,8‐tetrahydroquinaldine with a remarkable selectivity in mild reaction conditions by choosing the suitable solvent. The presence of a carboxylate ligand on the surface of the Ru NP led to an increase in the activity when compared to Ru/PVP catalyst. The stabilizing agent had also an impact on the selectivity, as carboxylate ligand modified catalysts promoted the selectivity towards 1,2,3,4‐tetrahydroquinaldine, with bulky carboxylate displaying the highest ones. [ABSTRACT FROM AUTHOR]

Five diastereomers of ruthenium(II) complexes based on quinolinophaneoxazoline ligands were investigated by vibrational circular dichroism (VCD) in the mid‐IR and CH stretching regions. Diastereomers differ in three sources of chirality: the planar chirality of the quinolinophane moiety, the central chirality of an asymmetric carbon atom of the oxazoline ring, and the chirality of the ruthenium atom. VCD, allied to DFT calculations, has been found to be effective in disentangling the various forms of chirality. In particular, a VCD band is identified in the CH stretching region directly connected to the chirality of the metal. The analysis of the calculated VCD spectra is carried out by partitioning the complexes into fragments. The anharmonic analysis is also performed with a recently proposed reduced‐dimensionality approach: such treatment is particularly important when examining spectroscopic regions highly perturbed by resonances, like the CH stretching region. [ABSTRACT FROM AUTHOR]

A series of sulfonamide azobenzenes bearing alkyl substituents of increasing steric bulk at the position ortho to the N=N bond and their corresponding chloro(hexamethylbenzene)ruthenium(II) complexes were synthesized. The latter bearing mono‐substituted ligands exhibited an exocyclic azo bond under the E configuration, and underwent reversible E→Z photoisomerization upon irradiation with visible light, followed by thermal Z→E back isomerization upon resting in the dark at 20 °C. In contrast, the corresponding 2,6‐dimethyl substituted azobenzene complex, while also exhibiting an exocyclic azo bond, was isolated as the Z‐isomer and underwent uncommon solvent dependent irreversible photodissociation of azobenzene ligand upon visible light irradiation. Valuable insights into the photophysical and structural properties of these complexes were gained by combination of computational and X‐ray diffraction studies. [ABSTRACT FROM AUTHOR]

A convenient protocol for the synthesis of 25,26,27-tribenzoyl-28-[((S)-1-diphenylphos- phanyl-propan-2-yl)oxy]-calix[4]arene via stereospecific methylation on Evans' oxazolidinone moiety was reported. According to the 13C NMR analysis of this phosphine, the calix[4]arene skeleton adopted a 1,3-alternate conformation. The latter conformation of the macrocycle and the (S)-chirality of the carbon atom bearing the methyl substituent were confirmed by a single-crystal X-ray diffraction study. After coordination of the phosphinated ligand to the dimeric [RuCl2(p-cymene)]2 organometallic precursor, the resulting arene–ruthenium complex was tested in the asymmetric reduction of acetophenone and alcohol was obtained with modest enantiomeric excess. [ABSTRACT FROM AUTHOR]

A series of new chelating bidentate (SS) alkylimidazole-2-thione-Ru(II)/Os(II) complexes (3ai, 3aii, 3aiii, 3bii/4aiii, 4bi, 4bii), and the tridentate (SNS) pyridine-2,6-diylimidazole-2-thione-Ru(II)/Os(II) complexes (5bi, 5civ/6bi, 6ci, 6civ) in the forms [MII(cym)(L)Cl]PF6 and [MII(cym)(L)]PF6 (M = Ru or Os, cym = η6-p-cymene, and L = heterocyclic derivatives of thiourea) respectively, were successfully synthesized. Spectroscopic and analytical methods were used to characterize the complexes and their ligands. Solid-state single-crystal X-ray diffraction analyses revealed a "piano-stool" geometry around the Ru(II) or Os(II) centers in the respective complexes. The complexes were investigated for in vitro chemotherapeutic activities against human cervical carcinoma (HeLa) and the non-cancerous cell line (Hek293) using the MTT assay. The compounds 3aii, 5civ, 5bi, 4aiii, 6ci, 6civ, and the reference drug, 5-fluorouracil were found to be selective toward the tumor cells; the compounds 3ai, 3aiii, 3bii, 4bi, 4bii, and 6bi, which were found not to be selective between normal and tumor cell lines. The IC50 value of the tridentate half-sandwich complex 5bi (86 ± 9 μM) showed comparable anti-proliferative activity with the referenced commercial anti-cancer drug, 5-fluorouracil (87 ± 15 μM). The pincer (SNS) osmium complexes 6ci (36 ± 10 μM) and 6civ (40 ± 4 μM) were twice as effective as the reference drug 5-fluorouracil at the respective dose concentrations. However, the analogous pincer (SNS) ruthenium complex 5civ was ineffective and did not show anti-proliferative activity, even at a higher concentration of 147 ± 1 μM. These findings imply that the higher stability of the chelating (SS) and the pincer (SNS) ligand architectures in the complexes improves the biological (anti-proliferative) activity of the complexes by reducing the chance of ligand dissociation under physiological conditions. In general, the pincer (SNS) osmium complexes were found to be more cytotoxic than their ruthenium analogues, suggesting that the anti-proliferative activity of the imidazole-2-thione-Ru/Os complexes depends on the ligand's spatial coordination, the nature of the metal center, and the charge of the metal complex ions. [ABSTRACT FROM AUTHOR]

New chiral phosphine‐amine‐ether (PNO) ligands of the general formula Ph2PCH(R1)(CH2)nCH(R1)N(R2)CH(R3)CH2OMe, where R1, R2, and R3 = H or Me, n = 0 or 1, and their ruthenium complexes of the type [RuCl2(PPh3)(PNO)] have been synthesized. The coordination compounds were characterized by 1D and 2D NMR spectroscopy, modeled by DFT calculations, and in one case analyzed by X‐ray crystallography. The combined spectroscopic and theoretical investigations revealed that the relative configuration of the stereogenic elements in the P–N and N–O backbone represents a crucial factor in determining the conformation of the pincer‐type chelates and may also affect the configuration of the coordinated stereogenic nitrogen in the NH subunit, an essential element of stereochemical communication in outer sphere bifunctional catalysis. The new complexes were applied in the asymmetric hydrogenation of fused ring bicyclic ketones (i.e., 1‐tetralone and 4‐chromanone derivatives), a challenging substrate class, where enantioselectivities up to 97% could be obtained. Based on the spectroscopic and theoretical studies and catalytic experiments, structural features affecting the stereochemistry of the coordination could be identified and a qualitative enantioinduction model has been proposed. [ABSTRACT FROM AUTHOR]

This study focuses on the cytotoxic activity of ruthenium(II) complexes, denoted as Ru1–8, which exhibit coordination with nitrogen (amine and amide), oxygen, and sulfur donor atoms, coupled with aryl and aliphatic wingtips. Specifically, the complexes were evaluated for their impact on the MCF‐7 breast cancer cell line. A systematic exploration of various parameters, including solubility, donor atom type, metal number, carbon chain length, aromatic ring presence, and molecular weight, was conducted to discern their influence on cytotoxic activity. The investigation involved assessing the cell viability across five concentrations (100, 50, 25, 10, and 5 μM) for five distinct monometallic and three bimetallic ruthenium complexes. Notably, Ru3, characterized by an extended carbon chain length (dodecyl) and favorable oil solubility facilitating cellular membrane penetration, demonstrated particularly promising results with the IC50 value of 1.03 μM. This research underscores the critical role of ligand design in shaping the cytotoxic potential of ruthenium(II) complexes and emphasizes the suitability of the Ru(II) p‐cymene complexes, as demonstrated by their robust activity against breast cancer in this specific investigation. [ABSTRACT FROM AUTHOR]

Glycerol dry reforming (GDR) turns glycerol and CO2 into valuable syngas. The present work aims to decipher the imperative role of Ru metal in enhancing the performance of Ni/Nd2O3.Gd2O3 in GDR. The unpromoted 15%Ni/Nd2O3.Gd2O3 and promoted 3%Ru-Ni/Nd2O3.Gd2O3 catalysts are synthesized via the ultrasonic-assisted impregnation method while XRD, FESEM-EDX, H2-TPR and CO2-TPD analyses are used to characterize the catalysts. In this study, the influence of reaction variables such as temperature and the CO2 to glycerol ratio (CGR) was investigated. In accordance with XRD and FESEM-EDX analyses, the promoted catalyst exhibited a more refined morphology and more uniform Ni dispersion than the unpromoted catalyst. From the reaction study, the promoted 3%Ru-15%Ni/Nd2O3.Gd2O3 gives higher glycerol conversion (91%), H2 yield (65%) and CO yield (80%) at a reaction temperature of 800 °C and CGR of 1. This is due to the higher number of available active sites as well as the excellent diffusion of Ni metal across the surface of the catalyst. However, as Ni metal is susceptible to carbon formation and is easily sintered, the production of carbon is unavoidable for the catalysts. The XRD and TPO analyses shown that the addition of Ru reduces the amount of carbon that accumulates on the site of the catalyst, which in turn reduces the rate of deactivation. [ABSTRACT FROM AUTHOR]

Convenient and highly sensitive detection of oxalate ions in body fluids is of crucial significance for disease prevention, diagnosis, and monitoring of treatment effectiveness. Establishing a simple solid-state electrochemiluminescence (ECL) sensing system for highly sensitive detection of oxalate ions is highly desirable. In this work, a solid ECL sensor was fabricated by immobilizing the commonly used emitter ruthenium(II)tris(bipyridine) (Ru(bpy)32+) on a double-layered bipolar silica nanochannel array film (bp-SNA)-modified electrode, enabling sensitive detection of oxalate ions in serum or urine samples. Cost-effective and readily available indium tin oxide (ITO) was used as the supporting electrode. Convenient fabrication of multiple negatively charged SNA (n-SNA)-modified ITO electrodes was achieved through the one-step Stöber solution growth method. Subsequently, a positive outer layer film (p-SNA) was rapidly prepared using an electrochemical-assisted self-assembly method. The double-layered bipolar silica nanochannel array film achieved stable immobilization of Ru(bpy)32+ on the electrode surface, facilitated by the electrostatic adsorption of Ru(bpy)32+ by n-SNA and the electrostatic repulsion by p-SNA. Utilizing oxalate ions as a co-reactant for Ru(bpy)32+, combined with the electrostatic enrichment of oxalate ions by p-SNA, the constructed sensor enabled highly sensitive detection of oxalate ions ranging from 1 nM to 25 μM and from 25 μM to 1 mM, with a detection limit (LOD) of 0.8 nM. The fabricated ECL sensor exhibited high selectivity and good stability, making it suitable for ECL detection of oxalate ions in serum and urine samples. [ABSTRACT FROM AUTHOR]

With the large consumption of fossil energy, people began spend attention and energy to find and unearth renewable energy, and electrolytic water hydrogen evolution is an ideal scheme. The key to hydrogen production from electrolytic water is to find an appropriate catalyst. Here, we have developed an efficient and durable catalyst by introducing Ruthenium into porous graphene oxide (Ru@PGO), When the current density is 10 mA cm−2, the the corresponding overpotential and Tafel slope are 40.2 mV and 89.68 mV dec−1 respectively, and its stability is very excellent. Through theoretical calculation, it is found that ΔGH* is low, and reveals the effect of pore structure and oxygen introduction on the catalyst. It provides a feasible scheme for the preparation of new catalyst for hydrogen evolution reaction (HER). [ABSTRACT FROM AUTHOR]

We are now well-positioned to comprehend carcinogenesis at a molecular level in greater detail due to significant technological advancements. Additionally, we are now able to rationally design and develop drug molecules with the ability to either selectively enhance or disrupt important biological processes, maximizing their therapeutic potential. This has heralded a new era in drug design. The heterometallic ruthenium–platinum complexes can be used as anticancer, photodynamic therapy, diabetes treatment, and molecular sensors for thiol-containing peptides due to their multifunctional interactions with nuclear DNA, mitochondrial DNA, RNA, and proteins. Compared to cisplatin and its Ru-based monometallic precursors, a significant number of reported ruthenium–platinum complexes exhibit enhanced cytotoxicity and tumor selectivity. Due to the covalent binding of the cis-PtIICl2 moiety to DNA, photoactive Ru(II)–Pt(II) complexes were designed to prelocalize a photodynamic therapy agent at the site of action. The development of ruthenium–platinum-based heterometallic complexes has recently advanced, opening up new avenues for the development of drugs that are more efficient. Metal complexes' potential as important cancer therapeutic agents will be the primary focus of this review. The development of ruthenium and platinum-based mono and mixed-metal complexes with therapeutic and biomedical applications are discussed in detail in this article. [ABSTRACT FROM AUTHOR]

The plasma atomic layer etching (ALE) process for Ru was developed with surface fluorination and ion bombardment. We employed two methods for surface fluorination: (i) fluorocarbon deposition using CHF3 or C4F8 plasmas and (ii) chemisorption and diffusion with CF4 plasma. C4F8 plasma generated a more fluorine rich fluorocarbon layer on the Ru surface compared with CHF3 plasma, and a higher etch per cycle (EPC) of 1.5 nm/cycle was achieved with C4F8 plasma, in contrast to the 0.6 nm/cycle achieved with CHF3 plasma. Moreover, chemisorption and diffusion with CF4 plasma yielded an EPC of 1.2 nm/cycle. The ALE process using CHF3 plasma shows the lowest fluorine residue and lowest surface roughness compared with the ALE process using C4F8 and CF4 plasmas. [ABSTRACT FROM AUTHOR]

The chloro-P,N-{diphenylphosphanyl-[(5-phenyl-1,3,4-oxadiazol-2-ylamino)phenyl-me- thyl]}(p-cymene)ruthenium(II) hexafluorophosphate complex (4) was obtained in two steps from diphenylphosphanyl-[(5-phenyl-1,3,4-oxadiazol-2-ylamino)phenyl-methyl] borane (2). In the first step, the oxadiazole ring coordinated with the ruthenium atom, resulting in the formation of the dichloro-N-{diphenylphosphanyl-[(5-phenyl-1,3,4-oxadiazol-2-ylamino)phenyl-methyl]borane}(p-cymene) ruthenium(II) complex (3). During the crystallization of the P,N-chelate ruthenium complex, the formation of conglomerate crystals was revealed by X-ray structure analysis. Only two stereoisomers were obtained with (S)-Ru and (R)-C configurations in the first complex and with (R)-Ru and (S)-C configurations in the second. This deracemization during crystallization is due to the formation of a hydrogen bond between the P,N-ligand and the chlorine atom (CH•••Cl). This supramolecular interaction allows the transfer of the ligand chirality to the metal center and decrees the stereochemistry of the ruthenium atom. [ABSTRACT FROM AUTHOR]

Area‐selective deposition (ASD) is a bottom‐up technique that provides numerous opportunities for nanoelectronic device fabrication. For example, advanced nano‐interconnect structures with barrierless metals like Ru in the contact holes can be created by Ru ASD with the bottom metals as growth surfaces and dielectrics as non‐growth surfaces. This work investigates Ru ASD by chemical vapor deposition (CVD) on industrially relevant substrates and nanopatterns and reveals how selectivity and growth rate are modulated by the CVD conditions and type of nanopattern. For low‐k dielectric/Cu substrate combinations, the selectivity reverses from metal‐on‐metal to metal‐on‐dielectric upon only changing the CVD co‐reagent from H2 to NH3. In contrast, NH3 is the preferred co‐reagent for SiO2‐TiN line patterns with critical dimension (CD) of 40 nm due to the more favorable adsorption and diffusion kinetics that cause growth rate and selectivity enhancement. Consistent with a diffusion‐mediated mechanism, the growth rate enhances even more for Ru CVD on nanoscale contact holes with CD of 10.5 nm, becoming 2.4 times higher as compared to unpatterned substrates. Thus, the ASD process changes drastically when pattern dimensions reach the nanoscale. The reported insights facilitate rational design of metal ASD processes for multiple applications in nanofabrication. [ABSTRACT FROM AUTHOR]

Anions of carboxylic acids are widely used as the promoters of ruthenium-catalyzed reactions of C—H activation of substrates containing an N-donar directing group. The promoting effect of structure of anions of aliphatic and (hetero)aromatic carboxylic acids on the C—H arylation of benzene, furan, and thiophene rings in benzo[d]imidazol-2-yl-(hetero)arenes, wherein the benzimidazole moiety played the role of N-donor directing group, was evaluated. It was found that the structural effect of carboxylate anion on the efficiency of promotion of the catalytic system can significantly vary upon the arylation of different substrates. Adamantane-1-carboxylic acid was proposed as the most effective and universal promoter, based on which a new efficient catalytic system was developed for the selective arylation of benzo[d]imidazol-2-yl-(hetero)arenes. [ABSTRACT FROM AUTHOR]

We have examined catalytic ammonia oxidation using ruthenium complexes bearing 2,2'-bipyridine-6,6'-dicarboxylate ligand and axial 3- and 4-substituted pyridine ligands under electrochemical conditions to study the substituent effect of the axial pyridine ligands. Ruthenium complex bearing 3,4-dibromopyridine ligands shows the highest catalytic activity to produce up to 145 equivalents of dinitrogen based on the catalyst. [ABSTRACT FROM AUTHOR]

The mononuclear and dinuclear ruthenium(III) complexes trans-Ph4P[RuIII(acac)2Cl2] (1), Ph4P[{RuIII(acac)Cl}2(μ-Cl)3] (2) and trans-Ph4P[RuIII(acac)2(NCS)2]·0.5C6H14 (3·0.5C6H14) were synthesized. Single crystals of 1, 2·H2O and 3·CH3CN suitable for X-ray crystal structure analyses were obtained through recrystallization from DMF for 1 and 2·H2O and from acetonitrile for 3·CH3CN. An octahedral Ru with bis-chelate-acac ligands and axial chlorido or κ-N-thiocyanido ligands (for 1 and 3·CH3CN) and triply µ-chlorido-bridged dinuclear Ru2 for 2·H2O were confirmed through the structure analyses. The Ru–Ru distance of 2.6661(2) of 2·H2O is indicative of the existence of the direct metal–metal interaction. The room temperature magnetic moments (μeff) are 2.00 and 1.93 μB for 1 and 3·0.5C6H14, respectively, and 0.66 μB for 2. The temperature-dependent (2–300 K) magnetic susceptibility showed that the strong antiferromagnetic interaction (J ≤ −800 cm−1) is operative between the ruthenium(III) ions within the dinuclear core. In the 1H NMR spectra measured in CDCl3 at 298 K, the dinuclear complex 2 showed signals for the acac ligand protons at 2.50 and 2.39 ppm (for CH3) and 5.93 ppm (for CH), respectively, while 1 and 3·0.5C6H14 showed signals with large paramagnetic shifts; −17.59 ppm (for CH3) and −57.01 ppm (for CH) for 1 and −16.89 and −17.36 ppm (for CH3) and −53.67 and −55.53 ppm (for CH) for 3·0.5C6H14. Cyclic voltammograms in CH2Cl2 with an electrolyte of nBu4N(ClO4) showed the RuIII → RuIV redox wave at 0.23 V (vs. Fc/Fc+) for 1 and the RuIII → RuII waves at −1.39 V for 1 and −1.25 V for 3·0.5C6H14 and the RuIII–RuIII → RuIII–RuIV and RuIII–RuIII → RuIII–RuIV waves at 0.91 V and −0.79 V for 2. [ABSTRACT FROM AUTHOR]

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Ruthenium is required to separate from high-level liquid waste (HLLW) because Ru is a valuable resource and is negatively influential on the vitrification process of HLLW. However, the separation of Ru is very challenging due to its complicated complexation properties. In this study, the adsorption and desorption characteristics of ruthenium on a synthesized SiPyR-N3 (weak-base anion exchange resin with pyridine functional groups) composite were investigated in nitric acid and nitrite–nitric acid systems, respectively, and the adsorption mechanism was explored. The experimental results showed that SiPyR-N3 has a significantly better adsorption effect on Ru in the nitrite–nitric acid system than in the nitric acid system, with an increase in the adsorption capacity of approximately three times. The maximum adsorption capacity of Ru is 45.6 mg/g in the nitrite–nitric acid system. The SiPyR-N3 possesses good adsorption selectivity (SFRu/other metal ions is around 100) in 0.1 M NO2−–0.1 M HNO3 solution. The adsorption processes of Ru in the two different systems are fitted with the pseudo-second-order kinetic model and Langmuir model for uptake kinetics and adsorption isotherms, respectively. The results obtained from the FT-IR, XPS, and UV absorption spectrometry indicate that NO2− was involved in the adsorption process either as a complexing species with the metal ions or as free NO2− from the solution. A 0.1 M HNO3 + 1 M thiourea mixed solution shows effective desorption performance, and the desorption efficiency can reach 92% at 328 K. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus (S. aureus) infection is a primary cause of otitis media (OM), the most common disease for which children are prescribed antibiotics. However, the abuse of antibiotics has led to a global increase in antimicrobial resistance (AMR). Nanozymes, as promising alternatives to traditional antibiotics, are being extensively utilized to combat AMR. Here, we synthesize a series of single-atom nanozymes (metal-C3N4 SANzymes) by loading four metals (Ag, Fe, Cu, Ru) with antibacterial properties onto a crystalline g-C3N4. These metal-C3N4 display a rob-like morphology and well-dispersed metal atoms. Among them, Ru-C3N4 demonstrates the optimal peroxidase-like activity (285.3 U mg–1), comparable to that of horseradish peroxidase (267.7 U mg–1). In vitro antibacterial assays reveal that Ru-C3N4 significantly inhibits S. aureus growth compared with other metal-C3N4 even at a low concentration (0.06 mg mL–1). Notably, Ru-C3N4 acts as a narrow-spectrum nanoantibiotic with relative specificity against Gram-positive bacteria. Biofilms formed by S. aureus are easily degraded by Ru-C3N4 due to its high peroxidase-like activity. In vivo, Ru-C3N4 effectively eliminates S. aureus and relieves ear inflammation in OM mouse models. However, untreated OM mice eventually develop hearing impairment. Due to its low metal load, Ru-C3N4 does not exhibit significant toxicity to blood, liver, or kidney. In conclusion, this study presents a novel SANzyme-based antibiotic that can effectively eliminate S. aureus and treat S. aureus-induced OM.

A lipophilic tricationic cobalt tris(chelate) complex of 2-guanidinobenzimidazole (GBI), [Co(GBI)3]3+ 3BArf– (23+ 3BArf–; BArf = B(3,5-C6H3(CF3)2)4), is prepared from the corresponding hydrophilic trichloride salt and Na+ BArf– or Ag+ BArf– under aqueous/organic biphasic conditions. This racemic chiral complex, which is obtained as a mer isomer and a tetradecahydrate as assayed by NMR and TGA, is an excellent catalyst for additions of dimethyl malonate and indole to trans-ß-nitrostyrenes (10 mol%), and cycloadditions of CO2 to epoxides (1 mol%; solvent-free). Average yields (84 %, 91 %, 81 %) and rates are slightly greater than those obtained with a monocationic ruthenium GBI complex [(η5-C5H5)Ru(CO)(GBI)]+ BArf– prepared earlier. Attempted crystallization of 23+ 3Cl– gives a tetramethanol solvate of a salt derived from loss of two molecules of HCl. This can be represented as [Co(GBI)(GBI–H)2]+ Cl−, and bond lengths and hydrogen bonding motifs are carefully analyzed, especially in the context of dominant chelate resonance forms.

The title compound, [RuGa2Cl6(C7H8)(CO)2] or [(CO)2(GaCl2)(η6-toluene)Ru]+[GaCl4]−, was isolated from the reaction of Ga2Cl4 with diphenylsilanediol in toluene, followed by the addition of Ru3(CO)12. The compound contains a ruthenium–gallium metal–metal bond with a length of 2.4575 (2) Å.

The title compound, [Ru(C12H14NO2)Cl(η6-C6H6)], exhibits a half-sandwich tripod stand structure and crystallizes in the orthorhombic space group P212121. The arene group is η6 π-coordinated to the Ru atom with a centroid-to-metal distance of 1.6590 (5) Å, with the (S)-2-(4-isopropyl-4,5-dihydrooxazol-2-yl)phenolate chelate ligand forming a bite angle of 86.88 (19)° through its N and phenolate O atoms. The pseudo-octahedral geometry assumed by the complex is completed by a chloride ligand. The coordination of the optically pure bidentate ligand induces metal centered chirality onto the complex with a Flack parameter of −0.056.

In this work, we investigated bonding features of 15 ruthenium(II) nitrile complexes of the type [Ru(tpy)(L)-(CH3CN)]n+, containing the tridentate tpy ligand (tpy = 2,2′:6′,2″-terpyridine) and various bidentate ancillary ligands L; 12 compounds originally synthesized by Loftus et al. [J. Phys. Chem. C 123, 10291–10299 (2019)] and three new complexes. We utilized local vibrational force constants derived from the local mode theory as a quantitative measure of bond strength complemented with the topological analysis of the electron density and the natural bond orbital analysis. Loftus et al. suggested that nitrile dissociation occurs after light induced singlet–triplet transition of the original complexes and they used as a measure of nitrile release efficiency quantum yields for ligand exchange in water. They observed larger quantum yields for complexes with smaller singlet–triplet energy gaps. The major goal of this work was to assess how the Ru–NC and Ru–L bond strengths in these 15 compounds relate to and explain the experimental data of Loftus et al., particularly focusing on the question whether there is a direct correlation between Ru–NC bond strength and measured quantum yield. Our study provides the interesting result that the compounds with the highest quantum yields also have the strongest Ru–NC bonds suggesting that breaking the Ru–NC bond is not the driving force for the delivery process rather than the change of the metal framework as revealed by first results of a unified reaction valley approach investigation of the mechanism. Compounds with the highest quantum yield show larger electronic structure changes upon singlet–triplet excitation, i.e., larger changes in bond strength, covalency, and difference between the singlet and triplet HOMOs, with exception of the compound 12. In summary, this work provides new insights into the interplay of local properties and experimental quantum yields forming in synergy a useful tool for fine tuning of existing and future design of new nitrile releasing ruthenium compounds. We hope that this work will bring theoretical and experimental studies closer together and serves as an incubator for future collaboration between computational chemists and their experimental colleagues. [ABSTRACT FROM AUTHOR]

In this work, we studied the characteristics of Cu-Cu bonding with a ruthenium passivation layer at low temperatures. It is confirmed that the ruthenium passivation layer is effective in preventing the formation of native copper oxide, and diffusion of the copper into the ruthenium passivation layer occurred sufficiently at 200°C. The Cu samples with the ruthenium passivation layer were successfully bonded at 200°C. They exhibited excellent shear strength of 17.16 MPa, and the specific contact resistance of $1.78\times 10 ^{-7}~\Omega \cdot $ cm2 at the bonding interface. With the results, we expect that along with improving the thermal budget of the bonding process, it will be able to contribute to improving the chip performance and reliability of heterogeneous integrated structures.

The chloro-P,N-{diphenylphosphanyl-[(5-phenyl-1,3,4-oxadiazol-2-ylamino)phenyl-me- thyl]}(p-cymene)ruthenium(II) hexafluorophosphate complex (4) was obtained in two steps from diphenylphosphanyl-[(5-phenyl-1,3,4-oxadiazol-2-ylamino)phenyl-methyl] borane (2). In the first step, the oxadiazole ring coordinated with the ruthenium atom, resulting in the formation of the dichloro-N-{diphenylphosphanyl-[(5-phenyl-1,3,4-oxadiazol-2-ylamino)phenyl-methyl]borane}(p-cymene) ruthenium(II) complex (3). During the crystallization of the P,N-chelate ruthenium complex, the formation of conglomerate crystals was revealed by X-ray structure analysis. Only two stereoisomers were obtained with (S)-Ru and (R)-C configurations in the first complex and with (R)-Ru and (S)-C configurations in the second. This deracemization during crystallization is due to the formation of a hydrogen bond between the P,N-ligand and the chlorine atom (CH•••Cl). This supramolecular interaction allows the transfer of the ligand chirality to the metal center and decrees the stereochemistry of the ruthenium atom.