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Abstract: Structure elucidation plays a critical role across the landscape of medicinal chemistry, including medicinal inorganic chemistry. Herein, we discuss the importance of structure elucidation in drug development and then provide three vignettes that capture key instances of its relevance in the development of biologically active inorganic compounds. In the first, we describe the exploration of the biological activity of the trinuclear Ru compound called ruthenium red and the realization that this activity derived from a dinuclear impurity. We next explore the development of Au‐based antitubercular and antiarthritic drugs, which features a key step whereby ligands were discovered to bind to Au through S atoms. The third exposition traces the development of As‐based antiparasitic drugs, a key step of which was the realization that the reaction of arsenic acid and aniline does not produce an anilide of arsenic acid, as originally thought, but rather an amino arsonic acid. These case studies provide the motivation for an outlook in which the development of Sb‐based antiparasitic drugs is described. Although antileishmanial pentavalent antimonial drugs remain in widespread use to this day, their chemical structures remain unknown.

This research focused on the synthesis and analysis of two novel Ru(II)-based complexes, cis-[RuCl(Hind)(phen)2]PF6 (FOR022) and cis-[Ru(Hind)2(phen)2](PF6)2 (FOR0E2), where Hind represents indazole and phen stands for 1,10-phenanthroline. These compounds were thoroughly characterized using various methods such as elemental analysis, spectroscopy techniques, and electrochemistry assay, confirming their structures. The research highlights the effectiveness of the compound FOR0E2 in exhibiting strong cytotoxic properties against various tumor cell lines, including HCT116, HepG2, HL-60, LNcaP, and PC-3, with half-maximal inhibitory concentration (IC50) values ranging from 10.7 to 25.2 μmol L−1. Additionally, FOR0E2 showed substantial leishmanicidal capabilities against both the promastigote and amastigote forms of L. amazonensis, with IC50 values of 5.7 μmol L−1 and 1.6 μmol L−1, respectively. These outcomes suggest that the inclusion of indazole in FOR022 and FOR0E2 significantly enhances their biological effectiveness, positioning it as a promising candidate for pharmacological treatments. [ABSTRACT FROM AUTHOR]

The synthesis of amides holds great promise owing to their impeccable contributions as building blocks for highly valued functional derivatives. Herein, we disclose the design, synthesis and crystal structure of a mixed-ligand ruthenium(II) complex, [Ru(η6-Cym)(O,O-PLY)Cl], (1) where Cym = 1-isopropyl-4-methyl-benzene and O,O-PLY = deprotonated form of 9-hydroxy phenalenone (HO,O-PLY). The complex catalyzes the aerobic oxidation of various primary amines (RCH2NH2) to value-added amides (RCONH2) with excellent selectivity and efficiency under relatively mild conditions with common organic functional group tolerance. Structural, electrochemical, spectroscopic, and computational studies substantiate that the synergism between the redox-active ruthenium and π-Lewis acidic PLY moieties facilitate the catalytic oxidation of amines to amides. Additionally, the isolation and characterization of key intermediates during catalysis confirm two successive dehydrogenation steps leading to nitrile, which subsequently transform to the desired amide through hydration. The present synthetic approach is also extended to substitution-dependent tuning at PLY to tune the electronic nature of 1 and to assess substituent-mediated catalytic performance. The effect of substitution at the PLY moiety (5th position) leads to structural isomers, which were further evaluated for the catalytic transformations of amine to amides under similar reaction conditions. [ABSTRACT FROM AUTHOR]

Herein we demonstrate an effective and facile end‐capping technique for ring‐opening metathesis polymerization (ROMP) using readily available allyl compounds as a new type of terminating agents. This new type of end‐capping reactions, which are based on the base‐promoted decomposition of ruthenocyclobutane intermediates, introduce diene moiety onto the chain end of ROMP polymers while simultaneously deactivating the ruthenium complex. These termination reactions are highly efficient, typically completing within 1 minute at 0 °C with >95 % end‐capping fidelity. [ABSTRACT FROM AUTHOR]

Due to its abundant resources and advantages in transportation and storage, methane fueled solid oxide fuel cells (SOFCs) are highly needed. In this work, an exceptional internal reforming catalyst comprising in-situ exsolved NiRu bimetallic nanoparticles and oxygen-deficient layered double perovskite LaBaMn 1.6 Ni 0.3 Ru 0.1 O 5+δ (r-LBMNR) was prepared. Compared to the cell with LaBaMn 1.6 Ni 0.4 O 5+δ (r-LBMN) catalyst, the cell with a Ru-doping r-LBMNR catalyst layer, exhibits superior peak power output of 336 mW cm−2 and better durability with a less decay rate of 0.014% per hour in CH 4 fuel. The enhanced electrochemical performance can be attributed to the high oxygen ion and electron conductivities of the catalyst and the coupling of Ni and Ru sites with the oxygen-deficient r-LBMNR matrix This coupling activates CH 4 and H 2 O, promotes the oxidation of C atoms in CH 4 molecules, and enables reversible hydrogen spillover, ultimately leading to the production syngas of CO(g) and H 2 (g). [Display omitted] • Trace Ru-doping facilitating the exsolution of nanoparticles. • LaBaMn 1.6 Ni 0.3 Ru 0.1 O 5+δ was modified with abundant O v and exsolved NiRu alloy. • Cell can operate stably over 220 h with a degradation rate of 0.014% h−1. [ABSTRACT FROM AUTHOR]

The design, synthesis, and characterization of novel BODPY‐based iridium and ruthenium complexes were reported. The structures of new compounds were fully characterized by FT‐IR, MALDI‐TOF mass analysis, elemental analysis, 1H, and 19F NMR spectroscopies. Precursor BODIPY was characterized by single‐crystal x‐ray diffraction technique for the first time. Photophysical properties including absorption and emission profiles and lifetimes were investigated via UV–vis absorption and emission spectroscopy. Photochemical properties were investigated via direct method, and the singlet oxygen production capabilities of new complexes were determined by NIR phosphorescence methods. BODIPY‐based new complexes were efficient at producing 1O2. Besides, both complexes showed more remarkable photosensitization ability than some commonly used photosensitizer based on BODIPY derivatives. This study points out that novel complexes are effective 1O2 photosensitizers that might be used for different application areas like photodynamic therapy. [ABSTRACT FROM AUTHOR]

Ruthenium (Ru) is an important platinum group metal for the manufacture of advanced materials owing to its chemical and physical properties. Generally, it is extremely difficult to dissolve Ru metal by using acidic solutions containing strong oxidizing agents. Therefore, pretreatments like alkali fusion roasting at high temperature are practiced to render the Ru metal soluble in aqueous solution. In this work, a simple procedure was proposed to dissolve Ru metal at room temperature without any pretreatments. The dissolution procedure consisted of two steps: (i) oxidation of Ru metal to RuO4– by using pure NaClO solution; (ii) reduction of RuO4– to stable Ru2OCl104– by using HCl as a reducing agent. The role of NaClO and HCl in the dissolution of Ru metal was discussed on the basis of the potential-pH diagram and the corresponding oxidation and reduction reactions. The effect of several parameters like the concentration of NaClO and HCl, temperature, time, and pulp density was investigated. Optimum conditions were obtained to completely dissolve Ru metal by using NaClO and HCl solution without alkali fusion. [ABSTRACT FROM AUTHOR]

The prepared Ru-Fe-O x /CC owns good catalytic performance, exhibiting small overpotentials of 32 mV, 28 mV for HER and 216 mV, 228 mV for OER in acidic and alkaline electrolytes, respectively. Remarkably, Ru-Fe-O x /CC||Ru-Fe-O x /CC electrolytic cell obtains small voltages of 1.48 V and 1.46 V to achieve 10 mA cm−2 for overall water-splitting in acidic and alkaline media with good stability. [Display omitted] Developing electrocatalysts with high activity and durability for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in both acidic and alkaline electrolytes remains challenging. In this study, we synthesize a self-supported ruthenium-iron oxide on carbon cloth (Ru-Fe-O x /CC) using solvothermal methods followed by air calcination. The morphology of the nanoparticle exposes numerous active sites vital for electrocatalysis. Additionally, the strong electronic interaction between Ru and Fe enhances electrocatalytic kinetics optimization. The porous structure of the carbon cloth matrix facilitates mass transport, improving electrolyte penetration and bubble release. Consequently, Ru-Fe-O x /CC demonstrates excellent catalytic performance, achieving low overpotentials of 32 mV and 28 mV for HER and 216 mV and 228 mV for OER in acidic and alkaline electrolytes, respectively. Notably, only 1.48 V and 1.46 V are required to reach 10 mA cm−2 for efficient water-splitting in both mediums, exhibiting remarkable stability. This research offers insights into designing versatile, highly efficient catalysts suitable for varied pH conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • MoAl 1-x B MBene is demonstrated to be a robust support for loading Ru nanoparticles. • Ru/MoAl 1-x B achieves the superior catalytic performance towards hydrogen generation. • Mechanism of AB hydrolysis over Ru/MoAl 1-x B is systematically investigated. • This is a first example to demonstrate MBene for boosting AB hydrolysis. The coordination between carrier and active metal is critical to the catalytic efficiency of ammonia borane (AB) hydrolysis reaction. In the present study, we report a new type of catalytic support based on molybdenum boride (MBene) MoAl 1-x B and demonstrate that the effective combination of MoAl 1-x B with Ru nanoparticles can realize the significantly enhanced performance for hydrogen generation. Owing to the efficient activation and dissociation of reactants, the optimal Ru/MoAl 1-x B catalyst achieves the large turnover frequency of 494 mol H2 mol Ru -1 min−1, high hydrogen generation rate of 119817 mL min−1 g Ru -1 and favorable apparent activation energy of 39.2 kJ mol−1 for the catalytic hydrolysis of AB under alkaline-free condition. The isotopic test suggests the cleavage of O H bond in H 2 O is the rate-determining step for hydrolysis reaction, while the fracture of B–H bond in AB is also well revealed by attenuated total reflectance (ATR)-Fourier transform infrared (FTIR) spectroscopy. Significantly, the flexible on-demand hydrogen generation is achieved by using chemical switches for on–off AB hydrolysis. This study provides a new support platform based on two-dimensional MBene to exploit efficient catalysts to boost AB dehydrogenation. [ABSTRACT FROM AUTHOR]

Stimulated by the increasing interest in ion adsorption effects on electrocatalytic reactions and by recent more detailed reports on the potential dependent adlayer structures formed on Ru(0001) in pure HClO4 and H2SO4 electrolytes, we revisited the oxygen reduction reaction (ORR) on structurally well‐defined Ru(0001) single crystal surfaces prepared under ultrahigh vacuum conditions. We demonstrate that the complex, potential‐dependent activity both for the ORR and for H2O2 formation is closely related to potential‐dependent changes in the composition and structure of the adlayer. Our results demonstrate the enormous effects adsorbed species can have on the ORR reaction characteristics, either by surface blocking, e. g., by (co‐)adsorbed bisulfate species, or by participation in the reaction, e. g., by *H transfer from adsorbed H or OH to O2. The comparison with results obtained on polycrystalline Ru, which differ significantly from Ru(0001) data, furthermore underlines the importance of using structurally well‐defined surfaces as a reference system for future theoretical studies. [ABSTRACT FROM AUTHOR]

The synthesis of sulfoxide‐functionalized NHC ligand precursors were carried out by direct and mild oxidation from corresponding thioether precursors with high selectivity. Using these salts, a series of cationic [Ru(II)(η6‐p‐cymene)(NHC‐SO)Cl]+ complexes were obtained in excellent yields by the classical Ag2O transmetallation route. NMR analyses suggested a chelate structure for the metal complexes, and X‐ray diffractometry studies of complexes 4 b, 4 c, 4dBArF and 4 e unambiguously confirmed the preference for the bidentate (κ2‐C,S) coordination mode of the NHC‐SO ligands. Interestingly, only one diastereomer, in the form of an enantiomeric pair, was observed both in 1H NMR and in the solid state for the complexes. DFT calculations showed a possible intrinsic energy difference between the two pairs of diastereomer. The calculated energy barriers suggested that inversion of the sulfoxide is only plausible from the higher energy diastereomer together with bulky substituents. Inverting the configuration at the Ru center instead shows a lower and accessible activation barrier to provide the most stable diastereomer through thermodynamic control, consistent with the observation of a single species by 1H NMR as a pair of enantiomers. All these complexes catalyse the β‐alkylation of secondary alcohols. Complex 4dPF6 bearing an NHC‐functionalised S‐Ad group has been further studied with different primary and secondary alcohols as substrates, showing high reactivity and high to moderate β‐ol‐selectivities. [ABSTRACT FROM AUTHOR]

Metallo-supramolecular polyelectrolytes (MEPE) have a variety of attractive properties concerning electrochromism, spin-crossover, rheology, and cell differentiation. Previous studies suggest that these polynuclear structures can be regarded as an assembly of individual subunits and mononuclear complexes can act as models. In this study, we synthesize a monotopic and a ditopic terpyridine ligand with pyridinium units as well as the corresponding iron and ruthenium MEPEs and their mononuclear counterparts. UV-vis studies show that the mononuclear complexes have similar absorption properties to MEPEs. Furthermore, all complexes and MEPEs exhibit electrochromic behavior. Yet only the MEPEs can be deposited on different substrates using a layer-by-layer approach which makes them attractive for applications as electrochromic devices. However, the low solubility particularly of the ruthenium MEPE, renders characterization in solution impractical. Hence, the use of mononuclear complexes with similar monotopic ligands as presented herein can act as a first instance to evaluate the properties of corresponding MEPEs, facilitating the development of metallo-supramolecular materials. [ABSTRACT FROM AUTHOR]

Aliphatic/aromatic nitrogen-substituted ligands have a very important role in ruthenium chemistry. Polydentate ligands with N-substituted pyridine rings are notable for their ability to easily modify the electronic and steric properties of ruthenium. In this study, the catalytic and biological activities of the [RuCl 2 (NNN)(CH 3 CN)] (NNN: 2,6-di(1H-pyrazol-3-yl)pyridine)) complex were examined for two different applications. Firstly, the superb Ru(II) complex was used to catalyze the methanolysis of NaBH 4 , and its initial rate was calculated as 69360 mLH 2 min−1g cat −1. Secondly, the biological activities of the superb Ru(II) complex were examined. Accordingly, it was determined that this homogeneous complex showed anti-microbial activity on all bacteria used in the study, among the Gram-positive bacteria used in the study, the best result belongs to the Bacillus cereus EMC 19 bacterium with 8 mm, while among the Gram-negative bacteria, the best zone diameter belongs to the Pseudomonas aeruginosa DSM 50071 bacterium with 5 mm. However, it was observed that zone diameters varied between 8 mm and 3 mm. Compared to the control group, it was determined that 0.25 mg/mL concentration had 94.87%, 0.5 mg/mL concentration 96.10%, 1 mg/mL concentration 96.50%, and 2 mg/mL concentration 97.09% cytotoxic activity on the SH-SY5Y cell line. it was determined that all doses of the superb Ru(II) complex used in the study showed anti-cancer activity, but the anticancer activity shown at low doses was statistically more significant at the p < 0.05 level. [Display omitted] • Use of homogeneous superb ruthenium(II) complex during methanolysis of NaBH 4. • Kinetic studies for the superb Ru(II) complex catalyzing the methanolysis of NaBH 4. • Calculation of activation parameters for catalytic the methanolysis reaction. • Investigation of anti-cancer and anti-microbial properties of superb Ru(II) complex. [ABSTRACT FROM AUTHOR]

An impact at Chicxulub, Mexico, occurred 66 million years ago, producing a global stratigraphic layer that marks the boundary between the Cretaceous and Paleogene eras. That layer contains elevated concentrations of platinum-group elements, including ruthenium. We measured ruthenium isotopes in samples taken from three Cretaceous-Paleogene boundary sites, five other impacts that occurred between 36 million to 470 million years ago, and ancient 3.5-billion- to 3.2-billion-year-old impact spherule layers. Our data indicate that the Chicxulub impactor was a carbonaceous-type asteroid, which had formed beyond the orbit of Jupiter. The five other impact structures have isotopic signatures that are more consistent with siliceous-type asteroids, which formed closer to the Sun. The ancient spherule layer samples are consistent with impacts of carbonaceous-type asteroids during EarthÕs final stages of accretion. [ABSTRACT FROM AUTHOR]

The efficient transformation of chemicals and electricity via electrocatalytic hydrogen evolution reaction (HER) plays a pivotal role in green hydrogen production. Both in academia and industry, the pursuit of designing and fabricating catalysts for HER that are not only efficient and robust but also environmentally friendly is of significant interest. In this work, a ruthenium catalyst doped with nickel was synthesized using a procedure-minimal and solvent-free method facilitated by microwave-assisted pyrolysis. The incorporation of alloying and optimized electronic structures has resulted in Ru-based nanocrystals that change the HER mechanism and enable enhanced activity. The optimal RuNi/C catalyst demonstrates an overpotential of only 15 mV at a current density of 10 mA cm−2, with a Tafel slope of 24 mV dec−1, surpassing the performance of the state-of-the-art Pt/C catalyst. Remarkably, the prepared catalyst exhibits admirable corrosion resistance, making it a highly promising candidate for green hydrogen production through seawater splitting. A ruthenium catalyst doped with nickel is synthesized through a solvent-free microwave treatment, and exhibits a Pt-surpassed activity towards HER. [Display omitted] • A ruthenium catalyst doped with nickel is synthesized via a green method. • The HER mechanism on ruthenium is transferred by the doped nickel. • The optimized catalyst shows a platinum-surpassed activity for HER. • Superior corrosion resistance and durability is achieved for seawater splitting. [ABSTRACT FROM AUTHOR]

Rational design and fabrication of efficient catalysts for overall water splitting in an integrated electrolyzer are essential for energy storage and conversion. Herein, an ultra‐small substitutional Zn‐doped Ru/RuO2 heterostructure (5.6 nm) is synthesized through a facile pyrolyzing strategy as an efficient bi‐functional electrocatalyst for water splitting in both acidic and alkaline media. Experiments demonstrate that introducing appropriate alien atoms into RuO2 with an amorphous state can effectively optimize the electron structure and expose abundant defects, and thus increasing the number of active sites and improving the intrinsic activity of RuO2 for the oxygen evolution reaction (OER). In addition, the high hydrogen adsorption capability of metallic Ru makes Ru‐RuO2 heterointerface suitable for water splitting. Notably, the Ru/ZnRuO2 displays low overpotentials at 10 mA cm−2 with only 184 mV for OER in 0.5 m H2SO4 and 35 mV for HER in 1.0 m KOH. Besides, the as‐synthesized Ru/ZnRuO2 displays cell voltages of 1.540 and 1.567 V (at 10 mA cm−2) for water splitting with remarkable durability for more than 220 and 100 h, respectively, in acidic and alkaline media. This work provides a facile strategy for designing pH‐universal electrocatalysts toward overall water splitting. [ABSTRACT FROM AUTHOR]

In this study, we investigated the mechanism of the inactivated hexene hydrogenation reaction catalyzed by a ruthenium (II) complex containing "N‐heterocyclic carbene" (NHC) ligands, specifically SIMes and CBA, using DFT calculations. Our focus was on RuH(OSO2CF3)(CO)(SIMes)(CBA), which exhibits excellent catalytic behavior. We tested the B3LYP‐D3, cam‐B3LYP, and TPSSh functionals. The hydrogenation reaction is initiated by the release of SIMes rather than CBA due to the lower associated dissociation energy. Our findings indicate a reaction mechanism consisting of two consecutive steps, each involving one hydrogen atom migration. The first step, considered as the kinetically limiting transition state, exhibits a Gibbs free activation barrier of 12.9 kcal mol−1. This step involves two asynchronous processes. The first one describes the migration of the ruthenium hydride to the internal carbon of the olefine function, transitioning from π to σ coordination mode, which promotes the formation of a bond between ruthenium and the terminal olefinic carbon. The second process involves the oxidation of ruthenium from Ru(II) to Ru(IV). This oxidation is crucial as it enables the decomposition of the H2 molecule into two hydrogen atoms bonded to the ruthenium atom. The geometrical structures of the Hidden Reaction Intermediate Ru(II) complex and the quasi‐transition state of the second process have been determined by means of the RIRC technique. The second step entails the migration of one of the newly formed hydrides of the Ru(IV) complex to the terminal olefinic carbon, resulting in the release of hexane with a weak activation Gibbs free energy of.8 kcal mol−1. Lastly, we explored the use of dichloromethane as a solvent, considering the PCM model. The presence of the solvent significantly decreases the energy dissociation of SIMes from 17.9 to 9.0 kcal mol−1, providing notable benefits. [ABSTRACT FROM AUTHOR]

In this study, we present the successful application of new and known stable 16‐electron ruthenium(II) pincer complexes POCOP, based on the naphthoresorcinate backbone, [Ru(X)(POCOP)(CO)] (X = H, Cl, Br, I, OCOCF3), in the catalytic alkylation of ketones and the coupling between amines and primary alcohols under mild conditions. These protocols demonstrated tolerance to a wide range of alcohols, ketones, and anilines, with reactions proceeding in high conversions and selectivity towards the hydrogenated ketones and the imines. The use of an excess of alcohol as the proton source facilitated the formation of the hydrogenated products. These results mark a significant advancement in the development of catalytic reactions with ruthenium POCOP pincer derivatives. [ABSTRACT FROM AUTHOR]

Controlling the interplay between relaxation and charge/energy transfer processes in the excited states of photocatalysts is crucial for the performance of artificial photosynthesis. Metal‐to‐ligand charge‐transfer triplet states (3MLCT*) of ruthenium(II) complexes are broadly implemented for photocatalysis, but an effective means of managing the triplets for enhanced photocatalysis has been lacking. Herein, We proposed a strategy to considerably prolong the triplet excited‐state lifetime by decorating a ruthenium(II) phosphine complex (RuP‐1) with pendent polyaromatic hydrocarbons (PAHs). Systematic studies demonstrate that in RuP‐4 decorated with anthracene, sub‐picosecond electron transfer from anthracene to 3MLCT* leads to a charge‐separated state that can mediate the formation of the intra‐ligand triplet state (3IL) of anthracene, resulting in an exceptionally long excited‐state up to several milliseconds. This triplet management strategy enables impressive photocatalytic reduction of CO2 to CO with a turnover number (TON) of 404, an optimized quantum yield of 43 % and 100 % selectivity, which is the highest reported performance for mononuclear photocatalysts without additional photosensitizers. RuP‐4 also catalyzes photochemical hydrogen generation under argon. This work opens up an avenue for regulating the excited‐state charge/energy flow for the development of long‐lived 3IL multi‐functional mononuclear photocatalysts to boost artificial photosynthesis. [ABSTRACT FROM AUTHOR]

Bis(2,2′-bipyridine)bis(isothiocyanato)ruthenium complexes are organo-metallic dyes having broad absorption properties in the visible region that are widely used in dye-sensitized opto-electronic devices. Here, we report the photocurrent measurement and stability studies of three Ru-complexes, cis-bis(isothiocyanato)bis(2,2′-bipyridyl-4,4′-dicarboxylato)ruthenium(II) (N3), its hydrophobic analogues cis-bis(isothiocyanato)(2,2'-bipyridyl-4,4'-dicarboxylato)(4,4'-di-nonyl-2'-bipyridyl)ruthenium(II) (Z-907) and hydrophilic analogues (di-tetrabutylammonium cis-bis(isothiocyanato)bis(2,2′-bipyridyl-4,4′-dicarboxylato)ruthenium(II), (N719). Z907 shows higher stability and photoelectric conversion efficiency after 2 h analysis than its hydrophilic counter-molecules, N3 and N719. The Z907-TiO2 system exhibited a 1.09 mA/cm2 photocurrent density after 2 h of analysis, with 78% of its performance retained even after an extended 48 h of analysis. The activity of N719-TiO2 and N3-TiO2 sharply decreased after 2 h of analysis, and significant desorption of the dye present on titanium oxide was also observed. This study suggests that hydrophobicity at the electrode-dye interface is a major factor supporting the stability of the dye-sensitized photoanode. [ABSTRACT FROM AUTHOR]

A novel tridentate ligand featuring an acridine core and pyrazole rings, namely 2,7- di-tert-butyl-4,5-di(pyrazol-1-yl)acridine, L, was designed and used to create two ruthenium(II) complexes: [RuL2](PF6)2 and [Ru(tpy)L](PF6)2. Surprisingly, the ligand adopted different coordination modes in the complexes: facial coordination for the homoleptic complex and meridional coordination for the heteroleptic complex. The electronic absorption and electrochemical properties were evaluated. Although both complexes exhibited favorable electronic properties for luminescence, neither emitted light at room temperature nor at 77 K. This study highlights the complex interplay between ligand design, coordination mode, and luminescence in ruthenium(II) complexes. [ABSTRACT FROM AUTHOR]

The performance of a set of bimetallic Ru-Co catalysts dispersed on the TiO2 anatase phase, synthesized by the co-deposition–precipitation with urea method, was tested in the CO2 production by the entire oxidation of C3H8. The presence of properly dispersed ruthenium nanoparticles on a Co/TiO2-anatase support was notably favorable for enhancing the C3H8 activity/selectivity. Likewise, an increase in the combined acidity (Brönsted and Lewis) was also observed, and the interaction between Ru0-CoOx species stabilized on TiO2 prompted the C3H8 oxidation at low temperature. The performance of bimetallic Ru-Co/TiO2 catalysts was enhanced by increasing Ru0 species and loading, showing more efficient C3H8 oxidation by the combination of Ru0-CoOx, as revealed by DRIFTS, XPS, H2-TPR, and HAADF-STEM characterization outcomes. The higher acidity of the catalysts containing Ru (1.5 wt%) and Co (3 wt%) as well as the reducibility enhancement of the Ru and Co species led to the best capacity of these catalysts for C3H8 oxidation to CO2 under the experimental conditions employed in this study. [ABSTRACT FROM AUTHOR]

Thanks to the ability of diazo derivatives to react either as 1,3‐dipoles and as carbenes after dinitrogen extrusion, combinations of oxa or aza benzonorbornadienes and diazomalonates afford polycyclic pyrazolidines via a three‐step sequence of (i) a highly diastereoselective [3+2]‐cycloaddition, (ii) a CpRu‐catalyzed carbene addition, and (iii) a second dipolar cycloaddition. Of importance, step (II) represents a unique access to novel bench‐stable N,N‐cyclic azomethine imines, which behave as effective 1,3‐dipoles in combination with electron‐poor dipolarophiles. Each step proceeds efficiently and the 3‐step process can be performed in one‐pot to yield a polycyclic pyrazolidine in excellent overall yield (90 %). [ABSTRACT FROM AUTHOR]

New half‐sandwich dinuclear arene ruthenium complexes of the general formula [(η6‐p‐cymene)Ru(k2‐S‐arylthiourea)Cl] (1–3) have been synthesized. The structural characterization of the ruthenium complexes has been established using analytical and various spectroscopic techniques. The bidentate coordination of the ligands and pseudo‐octahedral geometry around the ruthenium(II) ion are confirmed by the single‐crystal X‐ray diffraction technique. In vitro antiproliferative activity of the complexes has been studied by MTT (3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5 diphenyl tetrazolium bromide) assay against lung (A549), breast (MCF‐7), cervical (HeLa), ovarian (A2780) cancer cells, and non‐cancerous NIH‐3T3 mouse embryonic fibroblast cells. The results show that all the complexes exhibit excellent cytotoxicity towards all the cancer cells, with a low IC50 concentration compared with cisplatin. Further, the mode of cancer cell death has been examined by AO–EB (acridine orange/ethidium bromide), and DAPI (4',6‐diamidino‐2‐phenylindole) staining studies demonstrate the apoptosis‐associated cell morphological changes. Furthermore, the quantitative differentiation of late apoptosis has been elucidated by flow cytometry employing dual staining of Annexin V‐FITC and propidium iodide, which involves the transfer of phosphatidylserine to the external leaflet of the cytoplasmic membrane. [ABSTRACT FROM AUTHOR]

Given the tremendous success of (p‐cymene)RuII‐catalyzed C−H activation over the past 20 years, the community has long been aware that the development of chiral η6‐benzene (Ben) ligands should be a potent strategy for achieving the attractive but incredibly underdeveloped ruthenium(II)‐catalyzed asymmetric C−H activation. However, it has rarely been achieved due to the severe difficulty in developing proper chiral Ben ligands. In particular, designing chiral Ben ligands by connecting a benzene fragment to a chiral framework including benzene rings remained an unsolved challenge until this effort. Here we present a novel class of axially chiral Ben ligands derived from readily available (S)‐5,5′,6,6′,7,7′,8,8′‐octahydro‐1,1′‐bi‐2‐naphthol ((S)‐H8‐BINOL) in 4–8 steps. Notably, when coordinated with ruthenium, such chiral Ben ligand containing three benzene rings only forms one of the three possible isomeric BenRuII complexes. The related chiral BenRuII catalysts could effectively catalyze the asymmetric C−H activation of N‐sulfonyl ketimines with alkynes, affording a range of chiral spirocyclic sultams in up to 99 % yield with up to >99 % ee. These catalysts are expected to find broad applications in future. [ABSTRACT FROM AUTHOR]

An optimal cancer chemotherapy regimen should effectively address the drug resistance of tumors while eliciting antitumor‐immune responses. Research has shown that non‐apoptotic cell death, such as pyroptosis and ferroptosis, can enhance the immune response. Despite this, there has been limited investigation and reporting on the mechanisms of oncosis and its correlation with immune response. Herein, we designed and synthesized a Ru(II) complex that targeted the nucleus and mitochondria to induce cell oncosis. Briefly, the Ru(II) complex disrupts the nucleus and mitochondria DNA, which active polyADP‐ribose polymerase 1, accompanied by ATP consumption and porimin activation. Concurrently, mitochondrial damage and endoplasmic reticulum stress result in the release of Ca2+ ions and increased expression of Calpain 1. Subsequently, specific pore proteins porimin and Calpain 1 promote cristae destruction or vacuolation, ultimately leading to cell membrane rupture. The analysis of RNA sequencing demonstrates that the Ru(II) complex can initiate the oncosis‐associated pathway and activate both innate and adaptive immunity. In vivo experiments have confirmed that oncosis promotes dendritic cell maturation and awakens adaptive cytotoxic T lymphocytes but also activates the innate immune by inducing the polarization of macrophages towards an M1 phenotype. [ABSTRACT FROM AUTHOR]

Diarylacetylenes ArC≡CAr featuring condensed aromatic hydrocarbon fragments (Ar) such as naphthalene, anthracene, phenanthrene and pyrene were converted into vinylidene ligands by 1,2‐migration reactions within the coordination sphere of half‐sandwich complexes [MII(dppe)Cp]+ (MII = RuII, FeII). Comparison of the extent of conversion of the alkyne substrates to the vinylidene complexes [Ru{=C=CAr2}(dppe)Cp]+ with those obtained from acetylenes functionalized by smaller groups (H, CH3, Ph) show that the molecular volume (VM) of the migrating group and relief of steric congestion plays a role during the rearrangement process. Conversely, the H‐atoms from the larger condensed ring aryl groups that are in close proximity to the migrating sites also have a significant influence on the efficacy and extent of the reaction by restricting access of the alkyne to the metal center, resulting in a less effective migration reaction. This combination of competing steric factors (acceleration due to relief of steric congestion and restricted access of the alkyne moiety to the reaction site) is exemplified by the facile migration of 1‐pyryl entities and the low yields of vinylidene products formed from 1,2‐bis(9‐anthryl)acetylene. [ABSTRACT FROM AUTHOR]

The catalytic performance of ruthenium (Ru) in the synthesis and decomposition of ammonia (NH3) has attracted extensive attention and research. Considering its selective adsorption and excellent catalytic effect toward NH3, it holds significant potential in the field of ammonia detection. In this study, we present a high-performance NH3 sensor that was based on a catalytic metal gate field-effect transistor (FET) utilizing Ru nanoparticles as the sensitive gate (Ru-FET). The sensor exhibits a high response of 11.3% to 1 ppm of NH3 at room temperature, with quick response and recovery processes of 8 and 85 s, respectively. Meanwhile, the sensor possesses a detection range of 0.4-20 ppm along with good repeatability and selectivity. The exceptional performance of the Ru-FET sensor suggests the potential of judiciously combining sensitive materials and sensor structures to manufacture high-performance NH3 sensors operating at room temperature. [ABSTRACT FROM AUTHOR]

The hydrazine oxidation‐assisted H2 evolution method promises low‐input and input‐free hydrogen production. However, developing high‐performance catalysts for hydrazine oxidation (HzOR) and hydrogen evolution (HER) is challenging. Here, we introduce a bifunctional electrocatalyst α‐MoC/N−C/RuNSA, merging ruthenium (Ru) nanoclusters (NCs) and single atoms (SA) into cubic α‐MoC nanoparticles‐decorated N‐doped carbon (α‐MoC/N−C) nanowires, through electrodeposition. The composite showcases exceptional activity for both HzOR and HER, requiring −80 mV and −9 mV respectively to reach 10 mA cm−2. Theoretical and experimental insights confirm the importance of two Ru species for bifunctionality: NCs enhance the conductivity, and its coexistence with SA balances the H ad/desorption for HER and facilitates the initial dehydrogenation during the HzOR. In the overall hydrazine splitting (OHzS) system, α‐MoC/N−C/RuNSA excels as both anode and cathode materials, achieving 10 mA cm−2 at just 64 mV. The zinc hydrazine (Zn−Hz) battery assembled with α‐MoC/N−C/RuNSA cathode and Zn foil anode can exhibit 97.3 % energy efficiency, as well as temporary separation of hydrogen gas during the discharge process. Therefore, integrating Zn−Hz with OHzS system enables self‐powered H2 evolution, even in hydrazine sewage. Overall, the amalgamation of NCs with SA achieves diverse catalytic activities for yielding multifold hydrogen gas through advanced cell‐integrated‐electrolyzer system. [ABSTRACT FROM AUTHOR]

Five cationic ruthenium(II) chelates with the generic formula [Ru(S2C·NHC)3](PF6)2 were readily obtained upon cleavage of the [RuCl2(p-cymene)]2 dimer with representative imidazol(in)ium-2-dithiocarboxylate zwitterions (NHC·CS2) in the presence of KPF6. The homoleptic complexes were fully characterized by various analytical techniques and the molecular structure of one of them was determined by single-crystal X-ray diffraction analysis. As expected, it featured an octahedral RuS6 core surrounded by three imidazol(in)ium rings and their nitrogen substituents. The robustness of the Ru–S bonds combined with the chelate effect of the κ2-S,S′-dithiocarboxylate units and the steric protection imparted by bulky 1,3-diarylimidazol(in)ium groups most likely accounted for the outstanding stability of these species in solution. Cyclic voltammetry showed that the five homoleptic complexes featured characteristic waves for a monoelectronic redox process corresponding to the RuIII/RuII couple with E1/2 values ranging between 0.97 and 1.27 V vs. Ag/AgCl. This half-wave potential was clearly dependent on the nature of their ancillary ligands as the evolution of the Ep,ox values roughly paralleled the basicity sequence of the NHCs used to prepare them, in line with the trends observed when monitoring the chemical shifts of the CS2− unit on 13C NMR spectroscopy and the CS2− asymmetric stretching vibration wavenumbers on IR spectroscopy. [ABSTRACT FROM AUTHOR]

The synthesis and isolation of [Ru(Cp)(PCy2NPh2)(=C=CHPh]PF6 and [Ru(Cp*)(PCy2NCy2)(=C=CHPh)]PF6 was successfully accomplished. Use of these ruthenium vinylidene complexes for stoichiometric reactions with a variety of amines was performed. Upon reaction with alkyl amines, deprotonation of the Cβ hydrogen resulted in formation of acetylide complex [Ru(Cp*)(PCy2NPh2)(−C≡CPh)], and the species was confirmed through independent synthesis. In contrast, reaction of the less basic aryl amine aniline with [Ru(Cp)(PCy2NCy2)(=C=CHPh)]PF6 resulted in outer sphere addition to give a Fischer carbene product. [ABSTRACT FROM AUTHOR]

The first example of a bis(cyaphido) complex, trans‐[Ru(dppe)2(C≡P)2], is described, unequivocally demonstrating the synthetic accessibility and stability of complexes that feature more than one cyaphido ligand. Synthesis is achieved from the precedent cation [Ru(dppe)2(C≡P)]+ via sequential coordination and desilylation of the phosphaalkyne Me3SiC≡P. The heteroleptic analogue trans‐[Ru(dppe)2(C≡N)(C≡P)] is also prepared from the same cation and NaCN; both cyaphido complexes are structurally characterized, enabling the first direct comparison of cyaphide with cyanide, its isoelectronic and isolobal counterpart. This demonstrates an enhanced π‐acidity for −C≡P over −C≡N, while computational studies reveal also a higher π‐donor character for the cyaphido ligand. [ABSTRACT FROM AUTHOR]

In this work, we describe the synthesis of novel Ruthenium (II) complex-based salen Schiff bases. The obtained Ruthenium (II) complexes are characterized using usual spectroscopic and spectrometric techniques, viz., IR, UV-Vis, NMR (1H and 13C), powder X-ray diffraction, and HRMS. Further techniques, such as DTA-TGA and elemental analysis, are used to well establish the structure of the obtained complexes. Octahedral geometries are tentatively proposed for the new Ru(II) complexes. The measured molar conductance for the Ruthenium (II) complexes shows their electrolytic nature (4.24–4.44 S/m). The new Ru(II) complexes are evaluated for their antioxidant and antibacterial activities. The DPPH radical scavenging, FRAP, and total antioxidant capacity (TAC) assays show that the obtained complexes are more potent than the used positive control. They also exhibit promising antibacterial responses against pathogen bacteria: [RuH2L3Cl2] exhibits an important inhibition against Bacillus subtilis DSM 6633, with an inhibition zone of 21 ± 1.41 mm with an MIC value of 0.39 mg/mL, and Proteus mirabilis INH, with 16.50 ± 0.70 mm and an MIC value of 0.78 mg/mL, while [RuH2L2Cl2] exerts interesting antibacterial effects versus Bacillus subtilis DSM 6633 (21 ± 1.41 mm) and Proteus mirabilis INH (25.5 ± 0.70 mm) with equal MIC values of 0.97 mg/mL. [ABSTRACT FROM AUTHOR]

The (R,R)-Teth-TsDPEN-Ru(II) complex promoted the one-pot double C=O reduction of α-alkyl-β-ketoaldehydes through asymmetric transfer hydrogenation/dynamic kinetic resolution (ATH-DKR) under mild conditions. In this process, ten anti-2-benzyl-1-phenylpropane-1,3-diols (85:15 to 92:8 dr) were obtained in good yields (41–87%) and excellent enantioselectivities (>99% ee for all compounds). Notably, the preferential reduction of the aldehyde moiety led to the in situ formation of 2-benzyl-3-hydroxy-1-phenylpropan-1-one intermediates. These intermediates played a crucial role in enhancing both reactivity and stereoselectivity through hydrogen bonding. [ABSTRACT FROM AUTHOR]

Area selective deposition (ASD) is a promising IC fabrication technique to address misalignment issues arising in a top–down litho-etch patterning approach. ASD can enable resist tone inversion and bottom–up metallization, such as via prefill. It is achieved by promoting selective growth in the growth area (GA) while passivating the non-growth area (NGA). Nevertheless, preventing undesired particles and defect growth on the NGA is still a hurdle. This work shows the selectivity of Ru films by passivating the Si oxide NGA with self-assembled monolayers (SAMs) and small molecule inhibitors (SMIs). Ru films are deposited on the TiN GA using a metal-organic precursor tricarbonyl (trimethylenemethane) ruthenium (Ru TMM(CO)3) and O2 as a co-reactant by atomic layer deposition (ALD). This produces smooth Ru films (<0.1 nm RMS roughness) with a growth per cycle (GPC) of 1.6 Å/cycle. Minimizing the oxygen co-reactant dose is necessary to improve the ASD process selectivity due to the limited stability of the organic molecule and high reactivity of the ALD precursor, still allowing a Ru GPC of 0.95 Å/cycle. This work sheds light on Ru defect generation mechanisms on passivated areas from the detailed analysis of particle growth, coverage, and density as a function of ALD cycles. Finally, an optimized ASD of Ru is demonstrated on TiN/SiO2 3D patterned structures using dimethyl amino trimethyl silane (DMA-TMS) as SMI. [ABSTRACT FROM AUTHOR]

The zinc-rich intermetallic phases CaRu2Zn10, SrRu2Zn10 and EuRu2Zn10 were synthesized by induction-melting of the elements in sealed tantalum ampoules followed by annealing to increase the crystallinity. The samples were characterized by powder X-ray diffraction and the structures were refined from single crystal X-ray diffractometer data: new type, P42/nnm, a = 894.68(14), c = 518.44(9) pm, wR2 = 0.0830, 432 F 2 values, 22 variables for CaRu2Zn10, a = 907.01(10), c = 516.35(6), wR2 = 0.0469, 445 F 2 values, 22 variables for SrRu2Zn10 and a = 902.84(9), c = 515.91(5) pm, wR2 = 0.0469, 434 F 2 values, 22 variables for EuRu2Zn10. The three structures are new ordering variants of the aristotype ThMn12. They are discussed on the basis of a group-subgroup scheme and compared to the known superstructures CaCr2Al10, ErNi10Si2 and ScFe6Ga6. The calcium atoms within the Ca@Ru4Zn16 polyhedra have flattened tetrahedral ruthenium coordination, reducing the calcium site symmetry to 4 ‾ $\bar{4}$ 2m (instead of 4/mmm in the aristotype). Electronic structure calculations show a substantial charge transfer from calcium to ruthenium and an almost neutral zinc substructure. [ABSTRACT FROM AUTHOR]

Methods for producing drugs directly at the cancer site, particularly using bioorthogonal metal catalysts, are being explored to mitigate the side effects of therapy. Albumin‐based artificial metalloenzymes (ArMs) catalyze reactions in living mice while protecting the catalyst in the hydrophobic pocket. Here, we describe the in situ preparation and application of biocompatible tumor‐targeting ArMs using circulating albumin, which is abundant in the bloodstream. The ArM was formed using blood albumin through the intravenous injection of ruthenium conjugated with an albumin‐binding ligand; the tumor‐targeting unit was conjugated to the ArM using its catalytic activity, and the ArM was transported to the cancer site. The delivered ArM catalyzed a second tagging reaction of the proapoptotic peptide on the cancer surface, successfully suppressing cancer proliferation. This approach, which efficiently leveraged the persisting reactivity twice in vivo, holds promise for future in vivo metal‐catalyzed drug synthesis utilizing endogenous albumin. [ABSTRACT FROM AUTHOR]

The effectuation of pH‐universal electrocatalysis is highly attractive but still challenging for the hydrogen evolution reaction (HER). It appeals for not only the facilitated electron transport but also the kinetical proton mass transfer. In this study, a via‐hole Ru/MoO2 confined heterostructure is profiled as a metal‐support platform for the electron/mass transfer‐boosted pH‐universal HER studies. It is indicated that the as‐formed Ru─O─Mo bridge can modulate the electronic transport at the interface, and the proton adsorption and transfer are kinetically derived by the intensified metallic Ru─Ru bond. Resultantly, the Ru/MoO2 heterostructure stably attains the Pt‐beyond HER activity with an ultralow overpotential of 9.2 mV at 10 mA cm−2 in 1 m KOH, and also achieves the competitive HER activity and stability in the acidic/neutral electrolytes. Both the experimental and computational results reveal the accelerated HER kinetics is attributable to the intensive mass transfer through the interfacial Ru→MoO2 hydrogen spillover effect. This work opens up the opportunities to rationalize the advanced metal‐support HER electrocatalysts through the interfacial hydrogen spillover effect and metallic bond engineering. [ABSTRACT FROM AUTHOR]

Developing advanced electrocatalysts is crucial for alkaline hydrogen evolution reaction (HER). A balance in adsorption energy for each reaction intermediate on the catalyst determines the overall catalytic rate. This balance is closely linked to the d‐band center, which is, in turn, controlled by the electronic structure of the active sites. Herein, C60 molecules with electron‐withdrawing properties and manganese (Mn) atoms with electron‐donating properties to drive charge redistribution on Ru active sites are strategically utilized. The synergistic and complementary effects of C60 and Mn regulate the d‐band centers of Ru sites to an optimal position, optimizing both the water adsorption and hydrogen desorption of the synthesized Ru catalysts. The constructed MnRu/C60‐3 catalyst exhibits a low overpotential of 8 mV at 10 mA cm−2, a large TOF value of 15.5 s−1, and a high mass activity of 2.39 A mg−1Ru at an overpotential of 100 mV in 1.0 m KOH. The anion exchange membrane water electrolyzer, assembled with MnRu/C60‐3 as the cathode, demonstrates excellent water electrolysis performance and high stability under industrial operational conditions. This work offers a fresh perspective on catalyst design principles by manipulating the d‐band centers of active sites using two complementary components. [ABSTRACT FROM AUTHOR]

Ruthenium(II) polypyridyl complexes continue to raise increasing interest for the encouraging results in several biomedical areas. Considering their vast chemical‐physical repertoire, in particular the possibility to switch from the sensitization of reactive oxygen species (ROS) to ROS‐scavenging abilities by tuning the nature of their ligands, it is therefore surprising that their potential as antioxidants has not been largely investigated so far. Herein, we explored the antioxidant behaviour of the novel ruthenium compound [Ru(dbpy)(2,3‐DAN)Cl]PF6 (Ru1), featuring a benzoxazole derivative (dpby=2,6‐bis(4‐methyl‐2‐benzoxazolyl)pyridine) and the non‐innocent 2,3‐diamminonaftalene (2,3‐DAN) ligand, along with the reference tpy‐containing analogue [Ru(tpy)(2,3‐DAN)Cl]PF6 (Ru2) (tpy=2,2':6',2"‐terpyridine). Following the synthesis and the electrochemical characterization, chemical antioxidant assays highlighted the beneficial role of dpby for the ROS‐scavenging properties of Ru1. These data have been corroborated by the highest protective effect of Ru1 against the oxidative stress induced in SH‐SY5Y human neuroblastoma, which exerts pro‐survival and anti‐inflammatory actions. The results herein reported highlight the potential of Ru1 as pharmacological tool in neurodegenerative diseases and specially prove that the antioxidant properties of such compounds are likely the result of a non‐trivial synergetic action involving the bioactive ligands in their chemical architectures. [ABSTRACT FROM AUTHOR]

Engineering low‐cost electrocatalysts with desired features is vital to decrease the energy consumption but challenging for superior water splitting. Herein, we development a facile strategy by the addition of multivalence ruthenium (Ru) into the CoWO4/CC system. During the synthesis process, the most of Ru3+ ions were insinuated into the lattice of CoWO4, while the residual Ru3+ ions were reduced to metallic Ru and further attached to the interface between carbon cloth and CoWO4 sheets. The optimal Ru2(M)−CoWO4/CC exhibited superior performance for the HER with an overpotential of 85 mV@10 mA cm−2, which was much better than most of reported electrocatalysts, regarding OER, a low overpotential of 240 mV@10 mA cm−2 was sufficient. In comparison to Ru2(0)−CoWO4/CC with the same Ru mass loading, multivalence Ru2(M)−CoWO4/CC required a lower overpotential for OER and HER, respectively. The Ru2(M)−CoWO4/CC couple showed excellent overall water splitting performance at a cell voltage of 1.48 V@10 mA cm−2 for used as both anodic and cathodic electrocatalysts. Results of the study showed that the electrocatalytic activity of Ru2(M)−CoWO4/CC was attributed to the in‐situ transformation of Ru/Co sites, the multivalent Ru ions and the synergistic effect of different metal species stimulated the intrinsic activity of CoWO4/CC. [ABSTRACT FROM AUTHOR]

Rh(III) and Ru(II) complexes, [RhCl2(κ4‐N2N'P‐L)][SbF6] (1) and [RuCl2(κ4‐N2N'P‐L)] (2), were synthesised using the tetradentate ligand L (L=N,N‐bis[(pyridin‐2‐yl)methyl]‐[2‐(diphenylphosphino)phenyl]methanamine). In each case only one diastereomer is detected, featuring cis‐disposed pyridine groups. The chloride ligand trans to pyridine can be selectively abstracted by AgSbF6, with the ruthenium complex (2) reacting more readily at room temperature compared to the rhodium complex (1) which requires elevated temperatures. Rhodium complexes avoid the second chloride abstraction, whereas ruthenium complexes can form the chiral bisacetonitrile complex [Ru(κ4‐N2N'P‐L)(NCMe)2][SbF6]2 (5) upon corresponding treatment with AgSbF6. The complex [RhCl2(κ4‐N2N'P‐L)][SbF6] (1) has also been used to synthesise polymetallic species, such as the tetrametallic complex [{RhCl2(κ4‐N2N'P‐L)}2(μ‐Ag)2][SbF6]4 (6) which was formed with complete diastereoselectivity and chiral molecular self‐recognition. In addition, a stable bimetallic mixed‐valence complex [{Rh(κ4‐N2N'P‐L)}{Rh(COD)}(μ‐Cl)2][SbF6]2 (7) (COD=cyclooctadiene) was synthesised. These results highlight the significant differences in chloride lability between Rh3+ and Ru2+ complexes and demonstrate the potential for complexes to act as catalyst precursors and ligands in further chemistry applications. [ABSTRACT FROM AUTHOR]

Three new metal complexes of ceftriaxone (cef), incorporating platinum(IV), gold(III), and ruthenium(III), were prepared. The complexes were prepared using a 1:2 molar ratio between ceftriaxone sodium salt (Na2cef) to AuCl3, PtCl4, and RuCl3 salts in methanol solvent. The as-synthesized complexes were characterized using microanalytical techniques for C, H, N, and S elements, magnetic and molar conductance measurements, as well as spectroscopic methods including FTIR, ¹ H NMR, and UV-Vis. The shape, morphology and size calculations have been examined using SEM, TEM, and X-ray diffraction data. The cef complexes were six-coordinate systems possessing a distorted octahedral geometry. Through the oxygen of both triazine and carboxylate moieties with the chemical formulae [Au(cef)2(Cl)(H2O)] (I), [Pt(cef)2(Cl)2] (II), and [Ru(cef)2(Cl)(H2O)] (III) the antibiotic cef acts as a bidentate ligand towards three metal ions. The newly created complexes demonstrated antibacterial activity showing efficacy in comparison to the cef sodium ligands. In vitro, antibacterial assays against specific microorganisms were evaluated to assess the antibacterial activities of the complexes. Cytotoxicity assays for cef complexes were conducted for HepG-2 and MCF-7 cell lines, representing human hepatocellular carcinoma and breast cancer, respectively. A value of 22.4 g and 26.2 g for 50% inhibitory concentration (IC50), respectively, for HepG-2 and MCF-7 were obtained for [Ru(cef)2(Cl)(H2O)] (III). [ABSTRACT FROM AUTHOR]

In 2022, Beller and coworkers achieved the reversible hydrogenation of CO2 to formic acid using a Mn(I)–PN5P complex with excellent activity and reusability of the catalyst. To understand the detailed mechanism for the reversible hydrogen release–storage process, especially the effects of the transition metal center in this process, we employed DFT calculations according to which Ru(II) and Fe(II) are considered as two alternatives to the Mn(I) center. Our computational results showed that the production of formic acid from CO2 hydrogenation is not thermodynamically favorable. The reversible hydrogen release–storage process actually occurs between CO2/H2 and formate rather than formic acid. Moreover, Mn(I) might not be a unique active metal for the reversible hydrogenation of CO2 to formate; Ru(II) would be a better option. [ABSTRACT FROM AUTHOR]

Two novel cyclometalated ruthenium complexes, RC‐4 and RC‐5, featuring 1‐phenylisoquinoline and phenyl quinazoline as ancillary ligands, respectively, were synthesized to investigate their viability with the environmentally friendly copper (Cu) redox mediator, [Cu(bpye)2]2+/+. The modification of the ligand environment resulted in variations in the energetics, photophysical properties, and photovoltaic performance of RC‐4 and RC‐5 sensitizers. Despite RC‐5 sensitizer possessing a more positive ground state potential of 1.19 V versus the NHE, the RC‐4 sensitizer, with a lower HOMO level of 0.72 V versus NHE, exhibited superior photovoltaic performance along with the Cu electrolyte, attributed to its enhanced light harvesting ability, improved lifetime and reduced back electron transfer, contributing to higher Jsc, Voc, and PCE. [ABSTRACT FROM AUTHOR]

A new method is proposed to synthesize ethylenediamine complex [RuNO(en)2OH]I2 from K2[RuNOCl5], which increases the target product yield to 76%. Subsequent treatment of nitrate salt [RuNO(en)2 OH](NO3)2 with concentrated HF with the precipitation of HClO4 gives [RuNO(en)2F](ClO4)2 with a quantitative yield. According to the single crystal XRD data, in the [RuNO(en)2F]2+ cationic moiety, nitrosyl and fluoride are in the trans-position relative to each other, and in the ruthenium coordination environment, the equatorial plane is composed of four nitrogen atoms from ethylenediamine ligands. The 450 nm light irradiation of the [RuNO(en)2F](ClO4)2 complex at 80 K results in the formation of metastable linkage isomer MS1 with nitrosyl group coordination through the oxygen atom. According to the IR spectroscopic data, the population of MS1 is about 1%, and the respective vibrational band disappears when heated in a temperature range of 280-310 K. The activation parameters of the MS1–GS (ground state) transition according to the DSC data are Ea = 107.1±6.8 kJ/mol, lnk0 = 36.1±2.6. [ABSTRACT FROM AUTHOR]

Heterogeneous catalysts xRu/Ce0.75Zr0.25O2 (x = 1, 5 wt.%) are prepared by the sorption-hydrolytic precipitation. It is shown that these catalysts are active in the methanation of carbon dioxide. The composition and structural features of these compounds are studied by a complex of methods such as powder XRD, high-resolution electron microscopy, chemisorption, and X-ray photoelectron spectroscopy (XPS). It is established that catalysts obtained by the sorption-hydrolytic method contain the active component in a highly dispersed state. The catalyst with 1 wt.% Ru contains ruthenium compounds in the form of atomic clusters, while that with 5 wt.% Ru contains, along with ultrafine forms, also crystallized ruthenium-containing particles. It is shown that the initial catalysts contain oxide ruthenium compounds that are reduced to the metallic state under the methanation reaction conditions. In situ studies by powder XRD, XPS studies, temperature-programmed reduction in the hydrogen atmosphere (H2-TPR) show that metal ruthenium particles, which were obtained by the activation treatment of the catalysts as a result of heating in a hydrogen-enriched flow, promote the process of the partial reduction of the support material particles due to the spillover effect. [ABSTRACT FROM AUTHOR]

The catalytic efficacy of ruthenium (Ru)-exchanged montmorillonite, a well-established heterogeneous catalyst, was systematically explored to synthesize diverse bis(indolyl)methanes. The developed methodology consistently yielded the desired products with satisfactory to excellent yields, while notable advantages of the proposed approach encompassed minimal reaction times and solvent-free conditions. Furthermore, the method was characterized by its procedural simplicity, facile catalyst synthesis, ready accessibility of the starting materials from commercial sources, and the potential for catalyst recyclability. [ABSTRACT FROM AUTHOR]

This article provides an overview of the development, structure and activity of various metal complexes with anti-cancer activity. Chemical researchers continue to work on the development and synthesis of new molecules that could act as anti-tumor drugs to achieve more favorable therapies. It is therefore important to have information about the various chemotherapeutic substances and their mode of action. This review focuses on metallodrugs that contain a metal as a key structural fragment, with cisplatin paving the way for their chemotherapeutic application. The text also looks at ruthenium complexes, including the therapeutic applications of phosphorescent ruthenium(II) complexes, emphasizing their dual role in therapy and diagnostics. In addition, the antitumor activities of titanium and gold derivatives, their side effects, and ongoing research to improve their efficacy and reduce adverse effects are discussed. Metallization of host defense peptides (HDPs) with various metal ions is also highlighted as a strategy that significantly enhances their anticancer activity by broadening their mechanisms of action. [ABSTRACT FROM AUTHOR]

Photoinduced nitric oxide (NO) release for complexes [RuNO(L)2(NO2)2OH], where L=methyl isonicotinate (1), ethyl isonicotinate (2), methyl nicotinate (3) and ethyl nicotinate (4) was studied in DMSO, MeCN and water solutions (PBS, CTAB) using spectroscopic methods (UV‐vis, IR, EPR) and spectrometric techniques (ESI‐MS). Additionally, we present methodological evidence for improving the calculation of the quantum yield (QY) of NO release through the utilization of a combined IR‐UV‐vis‐spectroscopy flow‐through setup. According to DFT calculations, the production of nitric oxide occurs through the photoinduced cleavage of the Ru−NO bond, triggered by irradiation at 445 or 532 nm. This cleavage is a consequence of charge transfer from the orbitals of the Ru−OH group and the equatorial ligands (HOMO, HOMO‐1) to the Ru−NO antibonding orbital (LUMO). The cytotoxicity and photoinduced cytotoxicity of the investigated compounds were assessed against the breast adenocarcinoma cell line MCF‐7. Moreover, the investigation of the lipophilic properties of compounds 1–4 unveiled a significant influence of their lipophilicity on cytotoxic behavior, allowing for the modification of cytotoxicity through changes in the ligand L or by light irradiation. [ABSTRACT FROM AUTHOR]