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[Display omitted] • A simultaneous modified Ru3+ and CNTs enwrapped Na 3 V 2 (PO 4) 3 /C system is synthesized. • Ru3+ doping ensures the feasibility of replacing V3+ to expand the migration channel of Na+ and stabilizes structure. • Ex-situ XRD analysis at different SOC reveals that the sodium storage mechanism of Ru3+ doped Na 3 V 2 (PO 4) 3. • Ex-situ XRD/SEM/CV/EIS after cycling indicate improved kinetic characteristics and enhanced structural stability. • The modified Na 3 V 1.96 Ru 0.04 (PO 4) 3 /C@CNTs reveals superior rate capability and ultralong cyclic performance. Na 3 V 2 (PO 4) 3 (NVP) is an ideal cathode material for sodium ion battery due to its stable three-dimensional frame structure and high operating voltage. However, the low intrinsic conductivity and serious structural collapse limit its further application. In this work, a simultaneous optimized Na 3 V 1.96 Ru 0.04 (PO 4) 3 /C@CNTs cathode material is synthesized by a simple sol–gel method. Specifically, the ionic radius of Ru3+ is slightly larger than that of V3+ (0.68 Å vs 0.64 Å), which not only ensures the feasibility of Ru3+ replacing V3+ site, but also appropriately expands the migration channel of sodium ions in NVP and stabilizes the structure, effectively improving the diffusion efficiency of sodium ions. Moreover, CNTs construct a three-dimensional conductive network between the grains, reducing the impedance at the interface and effectively improving the electronic conductivity. Ex-situ XRD analysis at different SOC were performed to determine the change in the crystal structure of Ru3+doped Na 3 V 2 (PO 4) 3 , and the refinement results simultaneously demonstrate the relatively low volume shrinkage value of less than 3 % during the de-intercalation process, further verifying the stabilized crystal construction after Ru3+ substitution. Furthermore, the ex-situ XRD/SEM/CV/EIS after cycling indicate the significantly improved kinetic characteristics and enhanced structural stability. Notably, the modified Na 3 V 1.96 Ru 0.04 (PO 4) 3 /C@CNTs reveals superior rate capability and ultralong cyclic performance. It submits high capacities of 82.3/80.9 mAh g−1 at 80/120C and maintains 71.3/59.6 mAh g−1 after 14800/6250 cycles, indicating excellent retention ratios of 86.6 % and 73.6 %, respectively. This work provides a multi-modification strategy for the realization of high-performance cathode materials, which can be widely applied in the optimization of various materials. [ABSTRACT FROM AUTHOR]

A bis-(violurate)-based ruthenium(III) complex was synthesized in a pure form as nano-crystallites. Mass spectrum, elemental and thermal analysis, as well as molar conductance measurements, assigned the molecular formula [Ru(VA)2ClH2O]. FTIR, UV-vis, magnetic moment and ESR investigations suggested the structural formula as a distorted octahedron. Structural analysis by DFT calculations and processing of the PXRD data by the computer program Expo 2014 confirmed the proposed structure. Electronic and emission spectroscopy in addition to viscosity measurements displayed the greater binding capability of the [Ru(VA)2ClH2O] complex towards the studied biomolecules DNA and HSA as compared to uncomplexed violuric acid (VA). In vitro antiviral investigations against SARS-CoV-2 of violuric acid and the Ru(III) complex revealed greater activity in the case of the latter. Molecular docking studies reported that [Ru(VA)2ClH2O] binds more strongly to the spike protein of the tested virus cells (Vero-E6 cells), DNA, and HSA than the uncomplexed bis-(violurate) ligand system, consistent with the experimental results. [ABSTRACT FROM AUTHOR]

The carbonyl cluster compound [GeRu6(CO)18HI] is unique in regard to its structure and bonding with a GeRu6 cluster core, a planar GeRu4HI unit, extensive multi‐center bonding, and an aromatic ring current similar to benzene (9‐10 nA T−1). The open‐shell cluster core is a Ge‐centered five‐membered Ru4(Ru2) ring with CO ligands and an additional H and I atom, each bridging two Ru atoms on opposite sides of the cluster core. The compound is prepared at 130 °C in a weakly‐coordinating ionic liquid. [ABSTRACT FROM AUTHOR]

Metal–support interaction (MSI) is witnessed as an essential manner to stabilize active metals and tune catalytic activity for heterogonous water splitting. Kinetically driving the water electrolysis (WE) appeals for a rational MSI system with the coupled electron‐donating/accepting (e‐D/A) characters for hydrogen/oxygen evolution reactions (HER/OER). However, the metal stabilization effect by MSI will in turn restrict the deblocking of e‐D/A properties and challenge the full electrocatalytic optimization. This study profiles a heterostructure featuring metastable Ru clusters on defective NiFe hydroxide (Ru/d‐NiFe LDH) support as a low‐precious (≈2 wt%) catalytic platform for efficient WE. It is indicated that the interfacial oxygen vacancies can deviate the stable Ru 4d5 orbit to a metastable Ru2+δ state, and regulate the metal d‐band center levels toward the facilitated HER/OER processes. Resultantly, the Ru/d‐NiFe LDH heterostructure attains the ultralow overpotentials at 10 mA cm−2 for Pt‐beyond alkaline HER (18 mV) and OER (220 mV) with fast kinetics and durability. The symmetrical water electrolyzer delivers a promising voltage of 1.49 V at 10 mA cm−2 in 1 m KOH and efficient seawater splitting performance. This work carries interesting opportunities in rationalizing sophisticated metal‐support electrocatalysts through metal‐site metastabilization engineering. [ABSTRACT FROM AUTHOR]

The most challenging task for establishing a 103Ru/103mRh generator for Auger therapy, is to reach an effective separation between the two radionuclides because of the highly unpredictable, very complicated and poorly understood chemistry. In HCl, this work was able to evidence the formation of Ru colloids. It has been evidenced that the starting material of Ru, time and temperature have a strong influence on Ru speciation, but no polynuclear species of ruthenium–chloride was observed. This work has showed that it is fully possible to control the speciation of ruthenium, especially Ru(IV), within a mononuclear species; that is a huge step forward compared to literature. [ABSTRACT FROM AUTHOR]

Metal oxides are used as catalysts in energy and environmental applications. For instance, ruthenium(IV) oxides are oxygen evolution reaction catalysts in water splitting that have been investigated under highly acidic or alkaline conditions. Still, their stability and activity are limited under such harsh conditions. High-valent ruthenium ligand (L) complexes RuIV-L and RuV-L have been extensively studied for oxygen evolution reaction in non-aqueous environments. The new approach used herein is the combination of two high-valent ruthenium(IV) oxide (RuIV) and iron(VI) (FeVIO42−, FeVI) that yielded efficient oxygen evolution reaction activity under mild alkaline aqueous conditions, at pH 8.2 and 9.0. The easily available ruthenium(III) ion (RuIII) reacted with FeVI at a molar ratio of 0.25 ([RuIII]:[FeVI]) to produce in situ RuIV and unconsumed FeVI mixture solution, which had an onset potential around 1.40 V with a shift in onset potential of 260 mV and 150 mV with respect to RuIII and FeVI alone, respectively. The unique mixed solution of RuIV-FeVI had less resistance to perform the catalytic reaction. Here, we show that combining high-valent ruthenium(IV) oxide and iron(VI) under mild alkaline aqueous conditions exhibits superior performance for oxygen evolution reaction, making it a potential candidate for water splitting reaction. [ABSTRACT FROM AUTHOR]

Current space missions to Luna and Mars are considering to use the resources, which can be found on‐site at the destination. This strategy named in‐situ resource utilization (ISRU) saves valuable pay‐load capacities during the rocket launch from the earth surface. Specifically, in mars missions it is intended to produce the necessary rocket fuel CH4 for the back‐transit to earth via water electrolysis and subsequent CO2 methanation. The present study elaborates this concept and examines the question if polymeric reactors are feasible for heterogeneously catalyzed reactions in applications beyond earth. The study aims at providing a theoretical backbone for a proof‐of‐concept. The evaluation is conducted theoretically by design considerations and adds experimental results to show the general feasibility of polymeric reactors for applicable reaction conditions. [ABSTRACT FROM AUTHOR]

In this study, the promoting effects of ruthenium, palladium, and copper on the performance of a 15%Co-1%K/SiO2 catalyst were evaluated during CO2 hydrogenation in a fixed-bed reactor. Reactions were carried out at atmospheric pressure and 270 °C with H2/CO2 ratio of 3. All catalysts were characterized by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) and temperature-programmed reduction (TPR). Ruthenium, palladium and copper facilitated the reduction of cobalt oxides and increased cobalt dispersion. In terms of catalyst's performance, ruthenium addition led to increased CO2 conversion and methane selectivity with a detrimental effect on C5+ hydrocarbons. Palladium also presented a similar pattern at lower loading but a drop in CO2 conversion and increased reverse water–gas shift activity were observed at 3 wt % Pd loading. Promoting with copper resulted in decreased activity, methane selectivity and C5+ hydrocarbons productivity with a much higher CO selectivity. [ABSTRACT FROM AUTHOR]

Breast cancer cells have long been inhibited by polypyridine Ru(II) complexes, which are excellent antitumor agents. Due to their multi-targeting properties, this class of ruthenium complexes has received increasing attention as anticancer drug candidates approach to various cellular targets. The aim of this review is to give information about the ligands that were carefully chosen for ruthenium complexes. There has been a great deal of interest in using ruthenium-based complexes to treat breast cancer. Several species have shown potential as treatment candidates. However, further research is needed to determine how these agents affect the metastatic potential of breast cancer cells. The mechanism of action of Ru-based anticancer candidates NAMI-A and KP1019 during phase I clinical trials has been discussed. This article explains hormone-positive breast cancer and triple-negative breast-cancer treatment by using Ru complexes. Although platinum (Pt-based) anticancer medication is widely used in cancer treatment, a minor improvement has been seen and that is Platinum replaced with Ruthenium for its anticancer properties. We have also highlighted the best effective ruthenium-based complexes in treating T.N.B.C. (triple-negative breast cancer) here in this collection. [ABSTRACT FROM AUTHOR]

To gain mechanistic insights into the acetate-assisted cyclometallations of arylimines promoted by [RuCl2(p-cymene)]2 in polar protic media, DFT geometry optimizations (with M06 and ωB97X-D3 functionals and the cc-pVDZ-PP[Ru] basis set) followed by DLPNO-CCSD(T)/CBS energy evaluations were performed using benzaldimine as a model substrate and methanol as the solvent (with CPCM or SMD models). The calculation results show that coordination of the imine to an acetate ruthenium precursor is followed by anion (chloride or acetate) dissociation as the rate-determining step of the process. H-Bonding of two explicit MeOH to the anion reduces the calculated activation energy to ca. 23 kcal mol−1, in good agreement with the experimental half-life at room temperature. Subsequent AMLA/CMD C–H activation of the intermediate cationic complexes is a faster, reversible process. Alternative reaction pathways involving neutral diacetate ruthenium complexes offer AMLA/CMD transition state structures of lower energy but are precluded due to higher energy barriers for the initial ligand exchange processes at ruthenium. Solvent assistance accelerates the final chloride/acetate exchange processes on the cycloruthenate intermediates, particularly when compression in the condensed phase is taken into consideration. The performance of six DFT functionals (with the aug-pVTZ-PP[Ru] basis set) was assessed using the DLPNO-CCSD(T)/CBS reference energies. Neutral diacetate ruthenium complexes were incorrectly predicted as being kinetically relevant when using hybrid DFT methods (PBE0-D3(BJ), M06-2X or ωB97M-V). Good agreement between the calculated barrier heights and our benchmark energy results was obtained by using double-hybrid DFT methods. PWPB95 with D3(BJ) or D4 dispersion energy corrections was found to be the most accurate (ΔG≠ MUE of ca. 1 kcal mol−1). This study may aid our understanding of and help with further experimental investigations of synthetically useful carboxylate-assisted C–H bond functionalizations involving (N,C)-cyclometallated (p-cymene)Ru(II) intermediate complexes in sustainable polar protic solvents. [ABSTRACT FROM AUTHOR]

This study prepared a series of cerium oxide-based catalysts with different metal ruthenium loadings using an initial wet impregnation method. The results demonstrate that the prepared 1.4Ru/CeO 2 catalyst exhibits outstanding catalytic performance and activity stability. Under the condition where the Ru loading is only 1.4 wt%, the catalyst achieves almost complete NH 3 conversion at 500 °C, with a hydrogen production rate of 16.59 mmol gcat−1 min−1. Furthermore, after a 48-h long-term test, the activity remains stable. Characterization tests show that the metal ruthenium is uniformly distributed on the surface of cerium dioxide, with particle sizes ranging from 3 to 6 nm. Notably, a structure characterized by lattice stripes overlapping between the metal and support is observed. Increasing the Ru loading can enhance the surface acidity sites of the catalyst and the interaction between the metal and the support, which plays a crucial role in the long-term stability of the catalyst. Additionally, the abundant oxygen vacancies in cerium dioxide and its low cerium oxidation-reduction potential facilitate electron transfer to ruthenium, enhancing the adsorption of NH 3 and accelerating the desorption of N 2. [Display omitted] • The catalytic performance is related to the dispersion of the metal and the oxygen vacancies on the surface of the support. [ABSTRACT FROM AUTHOR]

Isomerization Metathesis (ISOMET) reaction is an emerging tool for "open loop" chemical recycling of polyethylene to propylene. Novel, latent N‐Alkyl substituted Cyclic(Alkyl)(Amino)Carbene (CAAC)–ruthenium catalysts (5a‐Ru, 3b‐Ru – 6c‐Ru) are developed rendering "inverted" chemical structure while showing enhanced ISOMET activity in combination with (RuHCl)(CO)(PPh3)3 (RuH) double bond isomerization co‐catalyst. Systematic investigations reveal that the steric hindrance of the substituents on nitrogen and carbon atom adjacent to carbene moiety in the CAAC ligand have significantly improved the catalytic activity and robustness. In contrast to the NHC‐Ru and CAAC‐Ru catalyst systems known so far, these systems show higher isomerization metathesis (ISOMET) activity (TON: 7400) on the model compound 1‐octadecene at as low as 3.0 bar optimized pressure, using technical grade (3.0) ethylene. The propylene content formed in the gas phase can reach up to 20% by volume. [ABSTRACT FROM AUTHOR]

A Grubbs‐type ruthenium complex bearing a tridentate anionic bisfluoroalkoxy‐carbene was synthesised and fully characterised. Under standard conditions, it proved to be inactive in olefin metathesis reactions, but the addition of HCl triggers its activity and allows the synthesis of a series of cyclic olefins and ethers as well as a stereoregular polynorbornene with an unexpectedly high content of trans‐configured double bonds, as found in commercially available polynorbornene (Norsorex®). Detailed structural studies and DFT calculations showed that the complex enters the catalytic cycle, but instead of performing a full turnover, it is caught as a stable intermediate that does not undergo further reactions. The addition of HCl causes dissociation of the fluoroalkoxy units, resulting in a compound that behaves similarly to standard Grubbs‐type complexes. To further understand this phenomenon, the corresponding Hoveyda‐Grubbs complex was also obtained and studied in detail; due to the absence of the phosphine ligand, its behaviour was different from that of its Grubbs‐type counterpart. [ABSTRACT FROM AUTHOR]

Single‐metal atomic sites and vacancies can accelerate the transfer of photogenerated electrons and enhance photocatalytic performance in photocatalysis. In this study, a series of nickel hydroxide nanoboards (Ni(OH)x NBs) with different loadings of single‐atomic Ru sites (w‐SA‐Ru/Ni(OH)x) were synthesized via a photoreduction strategy. In such catalysts, single‐atomic Ru sites are anchored to the vacancies surrounding the pits. Notably, the SA‐Ru/Ni(OH)x with 0.60 wt % Ru loading (0.60‐SA‐Ru/Ni(OH)x) exhibits the highest catalytic performance (27.6 mmol g−1 h−1) during the photocatalytic reduction of CO2 (CO2RR). Either superfluous (0.64 wt %, 18.9 mmol g−1 h−1; 3.35 wt %, 9.4 mmol−1 h−1) or scarce (0.06 wt %, 15.8 mmol g−1 h−1; 0.29 wt %, 21.95 mmol g−1 h−1; 0.58 wt %, 23.4 mmol g−1 h−1) of Ru sites have negative effect on its catalytic properties. Density functional theory (DFT) calculations combined with experimental results revealed that CO2 can be adsorbed in the pits; single‐atomic Ru sites can help with the conversion of as‐adsorbed CO2 and lower the energy of *COOH formation accelerating the reaction; the excessive single‐atomic Ru sites occupy vacancies that retard the completion of CO2RR. [ABSTRACT FROM AUTHOR]

The homogeneously catalyzed Guerbet upgrading of ethanol to butanol can be modulated by the application of partial H2 pressure before the reaction. Ruthenium(II) PNP pincer complexes with methylene‐extended acridine‐based ligands and singly‐chelated ruthenium(II) complexes with PN ligands perform best at very low catalyst loadings and upon the application of catalyst‐specific pre‐reaction partial H2 pressure. The combination of ruthenium(II) PNP pincer complexes and manganese(I) pincer complexes with MACHO‐type PNP ligands allows for even lower ruthenium loadings while retaining low base load and consumption, thus enabling high space‐time yields, catalyst productivity and recyclability. Mechanistically, Mn is proposed to stabilize coordinatively unsaturated Ru species and allow coordination of ethoxide to Ru instead of attacking the electrophilic ligand backbone based on NMR spectroscopy and X‐ray crystallography. [ABSTRACT FROM AUTHOR]

Due to the rapid progress of transition metal photocatalysis, developing novel and effective ruthenium photocatalysts and their corresponding heterogeneous counterparts is highly in demand. In this study, we first prepared tetraiodo-substituted 2,6-bis(1,2,3-triazol-4-yl)pyridine ruthenium(II), and further used this complex to construct 2,6-bis(1,2,3-triazol-4-yl)pyridine ruthenium(II) embedded porous organic polymers (POP-Ru). The as-prepared Ru(II) complex was employed as a photocatalyst, which showed higher photocatalytic activity than those of the commercial Ru(II) counterparts, but lower than that of the corresponding polymers. In particular, the polymer POP-Ru-1 has been disclosed to be highly efficient for the photosyntheses of thiocarbomates and disulfides, exhibiting a broad substrate scope. After simple separation workups, the photocatalyst could be recycled and reused for 10 times without obvious loss of its catalytic activity. [ABSTRACT FROM AUTHOR]

Single‐metal atomic sites and vacancies can accelerate the transfer of photogenerated electrons and enhance photocatalytic performance in photocatalysis. In this study, a series of nickel hydroxide nanoboards (Ni(OH)x NBs) with different loadings of single‐atomic Ru sites (w‐SA‐Ru/Ni(OH)x) were synthesized via a photoreduction strategy. In such catalysts, single‐atomic Ru sites are anchored to the vacancies surrounding the pits. Notably, the SA‐Ru/Ni(OH)x with 0.60 wt % Ru loading (0.60‐SA‐Ru/Ni(OH)x) exhibits the highest catalytic performance (27.6 mmol g−1 h−1) during the photocatalytic reduction of CO2 (CO2RR). Either superfluous (0.64 wt %, 18.9 mmol g−1 h−1; 3.35 wt %, 9.4 mmol−1 h−1) or scarce (0.06 wt %, 15.8 mmol g−1 h−1; 0.29 wt %, 21.95 mmol g−1 h−1; 0.58 wt %, 23.4 mmol g−1 h−1) of Ru sites have negative effect on its catalytic properties. Density functional theory (DFT) calculations combined with experimental results revealed that CO2 can be adsorbed in the pits; single‐atomic Ru sites can help with the conversion of as‐adsorbed CO2 and lower the energy of *COOH formation accelerating the reaction; the excessive single‐atomic Ru sites occupy vacancies that retard the completion of CO2RR. [ABSTRACT FROM AUTHOR]

In the evolving landscape of portable electronics, there is a critical demand for components that meld stretchability with optical transparency, especially in supercapacitors. Traditional materials fall short in harmonizing conductivity, stretchability, transparency, and capacity. Although poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) stands out as an exemplary candidate, further performance enhancements are necessary to meet the demands of practical applications. This study presents an innovative and effective method for enhancing electrochemical properties by homogeneously incorporating Ru(III) into PEDOT:PSS. These Ru(III) PEDOT:PSS complexes are readily synthesized by dipping PEDOT:PSS films in RuCl3 solution for no longer than one minute, leveraging the high specific capacitance of Ru(III) while minimizing interference with transmittance. The supercapacitor made with this Ru(III) PEDOT:PSS complex demonstrated an areal capacitance of 1.62 mF cm−2 at a transmittance of 73.5%, which was 155% higher than that of the supercapacitor made with PEDOT:PSS under comparable transparency. Notably, the supercapacitor retained 87.8% of its initial capacitance even under 20% tensile strain across 20,000 cycles. This work presents a blueprint for developing stretchable and transparent supercapacitors, marking a significant stride toward next-generation wearable electronics. [ABSTRACT FROM AUTHOR]

A new cooperative photoredox catalytic system, [RuII(trpy)(bpy)(H2O)][3,3′-Co(8,9,12-Cl3-1,2-C2B9H8)2]2, 5, has been synthesized and fully characterized for the first time. In this system, the photoredox catalyst [3,3′-Co(8,9,12-Cl3-1,2-C2B9H8)2]− [Cl6-1]−, a metallacarborane, and the oxidation catalyst [RuII(trpy)(bpy)(H2O)]2+, 2 are linked by non-covalent interactions. This compound, along with the one previously synthesized by us, [RuII(trpy)(bpy)(H2O)][(3,3′-Co(1,2-C2B9H11)2]2, 4, are the only examples of cooperative molecular photocatalysts in which the catalyst and photosensitizer are not linked by covalent bonds. Both cooperative systems have proven to be efficient photocatalysts for the oxidation of alkenes in water through Proton Coupled Electron Transfer processes (PCETs). Using 0.05 mol% of catalyst 4, total conversion values were achieved after 15 min with moderate selectivity for the corresponding epoxides, which decreases with reaction time, along with the TON values. However, with 0.005 mol% of catalyst, the conversion values are lower, but the selectivity and TON values are higher. This occurs simultaneously with an increase in the amount of the corresponding diol for most of the substrates studied. Photocatalyst 4 acts as a photocatalyst in both the epoxidation of alkenes and their hydroxylation in aqueous medium. The hybrid system 5 shows generally higher conversion values at low loads compared to those obtained with 4 for most of the substrates studied. However, the selectivity values for the corresponding epoxides are lower even after 15 min of reaction. This is likely due to the enhanced oxidizing capacity of CoIV in catalyst 5, resulting from the presence of more electron-withdrawing substituents on the metallacarborane platform. [ABSTRACT FROM AUTHOR]

The d5 electron configurations under the crystal field, spin–orbit coupling, and Coulomb interaction give rise to a plethora of profound ground states. Ruthenium perovskite oxides exhibit a number of unconventional properties yet the Ru4+ state (4 d 4 ) is usually stable in these materials. In this regard, Ru3+ ions in perovskite materials are expected to be a mesmerizing playground of 4 d 5 electron configurations. Here, we report measurements of x-ray photoemission spectroscopy on recently synthesized perovskite ruthenium oxide thin films, LaRuO3 and NdRuO3, whose valence state of the ruthenium ions is trivalent. We discuss correlation and spin–orbit effects from the valence band spectra, in particular an additional peak structure around 3–5 eV, reminiscent of the so-called 3 eV peak observed in Sr2RuO4. Moreover, we find that the core-level spectra of these materials are quantitatively different from those in other ruthenates, which possess Ru4+ ions, e.g., SrRuO3. We therefore argue that the core level spectra of LaRuO3 and NdRuO3 are peculiar to the Ru3+ states. [ABSTRACT FROM AUTHOR]

Nitrosyl ruthenium complexes have emerged as promising platforms for the controlled delivery of nitric oxide (NO) and nitroxyl (HNO), both of which possess significant therapeutic implications. Considering this scenario, we synthesized and characterized the metal complex cis‐[RuNO(phen)2(2MIM)]3+ and its precursors, where phen and 2MIM correspond to 1,10‐phenantroline and 2‐methylimidazole, respectively. Comprehensive structural elucidation was undertaken using a combination of spectroscopic and electrochemical methodologies, including XANES/EXAFS experiments. This structural data was further validated through DFT computational analyses. We demonstrated that such compound can release NO and HNO in the presence of thiol‐based substrates. Not only this, but the same metal complex can also delivery nitric oxide under irradiation with visible light (λ=460 nm). The nitrosyl complex and its derivatives displayed marked vasodilatory capabilities as evidenced in assays involving isolated rat aorta rings. They also exhibited commendable antioxidant activity in free radical scavenging assays. Collectively, based on these data, this nitrosyl ruthenium compound is a potential therapeutic candidate, especially in the field of cardiovascular pathology like atherosclerosis, thereby deserving further in‐depth investigations. [ABSTRACT FROM AUTHOR]

AbstractA series of mononuclear ruthenium(II) tetra-tert-butyl-phthalocyaninates bearing axial N-donor ligands [tBu4PcRu]L2 (L = trimethylamine, pyrazine, 4,4′-bipyridine and N-methyl-4,4′-bipyridinium iodide) as well as the binuclear complex [tBu4PcRu]2(BiPy)3 were synthesized starting from the complex with axially coordinated carbonyl group [tBu4PcRu](CO). All compounds have been characterized by NMR, UV-Vis and cyclic voltammetry. The latter allowed the determination of oxidation and reduction potentials, HOMO-LUMO gaps and revealed the possibility of electropolymerization of BiPy-containing complexes in clear contrast to complexes containing another bidentate ligand – pyrazine. Comparative electrochemical studies of the mono- and binuclear complexes [tBu4PcRu](BiPy)2 and [tBu4PcRu]2(BiPy)3 revealed that the phthalocyanine rings are not conjugated in the binuclear species. The remarkable dependence of singlet oxygen generation from axial ligands in ruthenium phthalocyaninates was observed: the complexes with carbonyl group [tBu4PcRu](CO) and with pyrazine molecules [tBu4PcRu](Pyz)2 show higher 1O2 quantum yields, whereas the complex with axially coordinated molecules of trimethylamine [tBu4PcRu](NMe3)2 and quaternized BiPy ligands [tBu4PcRu](BiPy-Me+)2 have the lowest ability to generate singlet oxygen. The revealed influence of axial ligands on key physicochemical properties paves the way for the design of new ruthenium phthalocyaninates with potential optoelectronic and biomedical applications. [ABSTRACT FROM AUTHOR]

Atom transfer radical addition (ATRA) of halogenated compounds with alkenes is well established but primary alkyl chlorides are understudied because of the difficult C−Cl bond activation. In this paper, we show that TONs of 61 can be achieved in the ATRA of ethyl chloroacetate onto styrene with [Cp*Ru(Cl)2(PPh3)] and 1,1′‐azobis(cyclohexanecarbonitrile) (ACHN) as a radical initiator, representing a three‐fold improvement compared to previous reports. New catalyst precursors of the type [Cp*Ru(Cl)2(PR3)] were synthesized and tested (R=Me, Et, Cy, Ph, p‐CF3C6H4 and p‐MeOC6H4). The kinetic reaction profiles were studied using in situ ATR−FTIR spectroscopy. Among these complexes, [Cp*Ru(Cl)2(PPh3)] gave the best yields while [Cp*Ru(Cl)2(PMe3)] showed the highest rate. While rates correlate with redox potentials (electronics), our investigation reveals that substrate sterics are important for the overall yield. Density functional theory calculations suggest an open‐shell singlet pathway, where polymerization is kinetically disfavored, explaining the selectivity towards ATRA products. [ABSTRACT FROM AUTHOR]

The porous architectures of oxygen cathodes are highly desired for high-capacity lithium–oxygen batteries (LOBs) to support cathodic catalysts and provide accommodation for discharge products. However, controllable porosity is still a challenge for laminated cathodes with cathode materials and binders, since polymer binders usually shield the active sites of catalysts and block the pores of cathodes. In addition, polymer binders such as poly(vinylidene fluoride) (PVDF) are not stable under the nucleophilic attack of intermediate product superoxide radicals in the oxygen electrochemical environment. The parasitic reactions and blocking effect of binders deteriorate and then quickly shut down the operation of LOBs. Herein, the present work proposes a binder-free three-dimensional (3D) porous graphene (PG) cathode for LOBs, which is prepared by the self-assembly and the chemical reduction of GO with triblock copolymer soft templates (Pluronic F127). The interconnected mesoporous architecture of resultant 3D PG cathodes achieved an ultrahigh capacity of 10,300 mAh g−1 for LOBs. Further, the cathodic catalysts ruthenium (Ru) and manganese dioxide (MnO2) were, respectively, loaded onto the inner surface of PG cathodes to lower the polarization and enhance the cycling performance of LOBs. This work provides an effective way to fabricate free-standing 3D porous oxygen cathodes for high-performance LOBs. [ABSTRACT FROM AUTHOR]

Two new monopyridyl‐based Anthracene and Pyrene ligands were synthesized and employed to design Ruthenium‐coordinated organometallic complexes, RuAnthra and RuPyrene, respectively. The ligands and their metal complexes were fully characterized by different analytical techniques, including multinuclear 1D‐ and 2D‐NMR, electrospray ionization‐mass spectrometry, UV–Vis, fluorescence spectroscopy, and elemental analysis. Furthermore, their photophysical properties were studied in different solvents with increasing polarity using UV–Vis and fluorescence spectroscopy, showing less or no significant solvolysis effect. The average emission lifetimes of the complexes were further determined using time‐resolved emission spectroscopy. Additionally, the ligands and their metal complexes showed excellent ability to generate singlet oxygen and can be useful for several important potential applications. [ABSTRACT FROM AUTHOR]

Acylated N‐acetyl hexosamine hemiacetals are known for their cytotoxicity. We have previously reported that cytotoxicity can be increased by replacing one or more acyloxy groups with fluorine. Herein, we present the synthesis of 4,6‐difluorinated d‐gluco‐ and 4‐fluorinated d‐galacto‐configured hexosamine‐derived glycoconjugates with organoruthenium or ferrocene complexes and their in vitro cytotoxicity against three cancer cell lines (A2780, SK‐OV‐3, and MDA‐MB‐231) and one noncancerous cell line (HEK‐293). The attachment of the organometallic moiety at the 2‐position significantly enhanced the cytotoxicity, especially against triple‐negative MDA‐MB‐231 and the cisplatin resistant SK‐OV‐3 cancer cells. We observed a clear significance of an unprotected and acetyl protected anomeric hydroxyl for the cytotoxicity. Glycoconjugates with a non‐hydrolysable organic or organometallic group at the anomeric position were generally nontoxic. A more detailed analysis revealed that, in particular, complexes with the ruthenium tetrazene complex induced apoptosis in both SK‐OV‐3 and MDA‐MB‐231 cells, as demonstrated by western blot analysis and Annexin V‐FITC/PI staining. The structures of the two most cytotoxic organoruthenium and ferrocene glycoconjugates were confirmed by X‐ray diffraction analysis. [ABSTRACT FROM AUTHOR]

[Display omitted] A series of novel ruthenium(ii) complexes with nitron-type N-heterocyclic carbene ligands containing chelating (N -arylcarbamoyl)methyl or carboxymethyl groups have been synthesized. Their evaluation as precatalysts in the hydrogenation of ketones has revealed that the complex containing three N -mesityl groups (one on the carbamoyl- methyl moiety and two on the triazole moiety) is the most efficient one. [ABSTRACT FROM AUTHOR]

The cyclometalated terpyridine complexes [Ru(η2-OAc)(NC-tpy)(PP)] (PP = dppb 1, (R,R)-Skewphos 4, (S,S)-Skewphos 5) are easily obtained from the acetate derivatives [Ru(η2-OAc)2(PP)] (PP = dppb, (R,R)-Skewphos 2, (S,S)-Skewphos 3) and tpy in methanol by elimination of AcOH. The precursors 2, 3 are prepared from [Ru(η2-OAc)2(PPh3)2] and Skewphos in cyclohexane. Conversely, the NNN complexes [Ru(η1-OAc)(NNN-tpy)(PP)]OAc (PP = (R,R)-Skewphos 6, (S,S)-Skewphos 7) are synthesized in a one pot reaction from [Ru(η2-OAc)2(PPh3)2], PP and tpy in methanol. The neutral NC-tpy 1, 4, 5 and cationic NNN-tpy 6, 7 complexes catalyze the transfer hydrogenation of acetophenone (S/C = 1000) in 2-propanol with NaOiPr under light irradiation at 30 °C. Formation of (S)-1-phenylethanol has been observed with 4, 6 in a MeOH/iPrOH mixture, whereas the R-enantiomer is obtained with 5, 7 (50–52% ee). The tpy complexes show cytotoxic activity against the anaplastic thyroid cancer 8505C and SW1736 cell lines (ED50 = 0.31–8.53 µM), with the cationic 7 displaying an ED50 of 0.31 µM, four times lower compared to the enantiomer 6. [ABSTRACT FROM AUTHOR]

The need for abundant, sustainable, and clean energy is becoming increasingly important in the modern world due to continuous population growth and industrial expansion. Hydrogen (H2) has been identified as a potential energy carrier due to its high gravimetric energy density. Because H2 is not frequently found in its molecular form, it has to be obtained through various methods such as steam methane reforming, coal gasification, fossil fuels, and electrochemical techniques. H2 produced via PEMWE has proved to be an efficient method compared to other electrolysers. The limiting factor of a PEM electrolyser system is the OER catalyst. Commercially, IrO2 and RuO2 are used; however, both these metals are rare and expensive. Current research reports the use of binary metal oxides as an alternative OER catalyst to decrease the overall CAPEX costs. Various synthesis methods are available, with the Adams’ fusion method being the simplest. Characterisation techniques used to evaluate the performance of these catalysts include cyclic voltammetry (CV), linear scan voltammetry (LSV), XRD, XRF, SEM/EDS, and chronopotentiometry. Hydrogen as a clean fuel has a broad potential for use across all sectors, including transportation, residential, and industrial. In recent years, extensive research has been done on all aspects of hydrogen production, storage, and transportation. This review paper aims to study other bimetallic metals to reduce the Ir content used as an oxidative evolution reaction to reduce the capital cost of the PEM electrolyser. To produce green hydrogen that could reduce the carbon footprint in several industrial processes. [ABSTRACT FROM AUTHOR]

This study used micro-analyses, (FTIR, UV-Vis) spectra, magnetic, thermogravimetric, X-ray powder diffraction (XRD) patterns, and transmittance electron microscopy (TEM) techniques to characterize three synthesized theophylline (TPH) complexes with ruthenium(III), platinum(IV), and iridium(III) metal ions. The metal ions indicated above were found to align with the TPH drug chelate as a mono-dentate ligand via the deprotonated NH group at the nitrogen atom position N7, as verified by FTIR measurements. Additionally, the complexes conductivity and magnetic susceptibility were examined. The octahedral geometry for the synthesized complexes was proposed by the current data. Except for the iridium(III) complex, which has a non-electrolytic nature due to the presence of a chlorine atom inside the chelation sphere, the molar conductivity of the complexes in DMSO solution was electrolyte in nature. Theophylline complexes with a (metal: ligand) stoichiometry of 1:2 were produced. The TPH complexes have also been tested in vitro against G(+) bacteria (Bacillus subtilis and Staphylococcus Aureus) and G(-) bacteria (Pseudomonas aeruginosa and Escherichia coli) to evaluate their antibacterial efficacy. Human breast and liver cancer cell lines were used as a test for the TPH complexes in vitro anti-cancer properties. [ABSTRACT FROM AUTHOR]

Ruthenium(III), gold(III), and iridium(III) trimethoprim drug (TMP) complexes were synthesized and analyses via microanalytical approach (C, H, N analysis), magnetic, molar conductance, and FTIR, 1H NMR, XRD, and UV-Vis spectroscopy. Through two nitrogen atoms of --NH2 amino groups, the TMP drug coordinated as a bidentate ligand towards the corresponding three metal ions. The geometrical structure of the compounds ruthenium(III), gold(III), and iridium(III) is octahedral and consists of two TMP molecules, two coordinated chlorine atoms, and one uncoordinated chlorine atom. The antibacterial properties of TMP complexes have been investigated through the use of many bacterial species, including Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, and Escherichia coli. Additionally, the generated complexes' anticancer properties against HepG-2 (human hepatocellular carcinoma) and MCF-7 (human breast cancer cell line) have been assessed. In contrast to those of clinically used antibiotics, the inhibition zone of ruthenium and iridium(III) complexes was in the low efficiency range, and the antibacterial activity of gold(III) complexes was moderate. This article discusses the possibilities and prospects for this family of metallodrugs as antibacterial or anticancer medicines. [ABSTRACT FROM AUTHOR]

Ru(II)‐arene compounds are being investigated as anticancer agents due to the biocompatibility of ruthenium and their structural diversity. Two newly synthesized Ru(II) complexes, [RuCl(η6‐p‐cymene)(3‐DNPH)] (chlorido(η6‐p‐cymene)(3‐nitrophenylhydrazine‐k2N,N′)ruthenium(II)) (1) and [RuCl(η6‐p‐cymene)(3‐CNPH)] (chlorido(3‐chlorophenylhydrazine‐k2N,N′)(η6‐p‐cymene)ruthenium(II)) (2), are experimentally (IR, NMR) and theoretically (B3LYP/6‐31+G(d,p)(H,C,N,Cl)/LanL2DZ(Ru)) characterized. Experimental and theoretical values of 1H and 13C chemical shifts and position of the most intense vibrational bands showed high correlation coefficients and low mean absolute errors, proving the predicted structure and applicability of the selected level of theory. Cell viability studies performed on MDA‐MB‐468, BT‐474, and PC3 cells using MTT and CV assay indicated the activity of the second complex similar to the activity of cisplatin towards BT‐474 breast cancer cells. The spectrofluorimetric measurements of Bovine Serum Albumin showed the binding process's spontaneity of complexes and protein, with a binding energy of around −30 kJ mol−1. Detailed molecular docking analysis allowed the elucidation of the binding mechanism through specific intermolecular interactions. Both compounds showed a higher affinity towards BSA than naproxen and cisplatin. Molecular docking simulations proved the spontaneity of the complexes binding to DNA. Based on these promising results, further biological examinations of these compounds are advised. [ABSTRACT FROM AUTHOR]

Highlights: Heterostructure constructed via confining crystalline ruthenium nanodomains by hafnium dioxide matrix was fabricated through a two-step annealing method for overall water splitting. The synergistic effect of hafnium dioxide modification and small crystalline domain formation significantly alleviates the over-oxidation of ruthenium. Durable and efficient bi-functional catalyst, that is capable of both oxygen evolution reaction and hydrogen evolution reaction under acidic condition, are highly desired for the commercialization of proton exchange membrane water electrolysis. Herein, we report a robust L-Ru/HfO2 heterostructure constructed via confining crystalline Ru nanodomains by HfO2 matrix. When assembled with a proton exchange membrane, the bi-functional L-Ru/HfO2 catalyst-based electrolyzer presents a voltage of 1.57 and 1.67 V to reach 100 and 300 mA cm-2 current density, prevailing most of previously reported Ru-based materials as well as commercial Pt/C||RuO2 electrolyzer. It is revealed that the synergistic effect of HfO2 modification and small crystalline domain formation significantly alleviates the over-oxidation of Ru. More importantly, this synergistic effect facilitates a dual-site oxide path during the oxygen evolution procedure via optimization of the binding configurations of oxygenated adsorbates. As a result, the Ru active sites maintain the metallic state along with reduced energy barrier for the rate-determining step (*O→*OOH). Both of water adsorption and dissociation (Volmer step) are strengthened, while a moderate hydrogen binding is achieved to accelerate the hydrogen desorption procedure (Tafel step). Consequently, the activity and stability of acidic overall water splitting are simultaneously enhanced. [ABSTRACT FROM AUTHOR]

The development of stable and efficient electrocatalysts based on metal-organic frameworks represents a main challenge for the overall water splitting process. Here, the ferrocene-based nickel metal-organic framework (NiFc-MOF) on nickel foam (NF) was synthesized using nickel chloride and 1, 1′-ferrocenedicarboxylic acid (FcDA) via a simple solvothermal method, and Ru nanoparticles (NPs) were reduced by FcDA and in situ grown on the surface of NiFc-MOF nanosheets. The as-prepared cactus-like Ru 0.3 @NiFc-MOF exhibits high electrocatalytic activity for hydrogen evolution reaction (HER) with a low overpotential of 25 mV@10 mA cm−2 and a Tafel slope of 45.05 mV dec−1. To reach a current density of 10 mA cm−2 for the oxygen evolution reaction (OER), a low overpotential of 210 mV was required. The assembled water electrolysis cell using Ru 0.3 @NiFc-MOF as bifunctional electrocatalysts only requires a voltage of 1.47 V to achieve a current density of 10 mA cm−2, indicating excellent electrolytic water splitting performance. In addition, the electrocatalytic activity of Ru 0.3 @NiFc-MOF's can keep the stability for 120 h Ru 0.3 @NiFc-MOF exhibits exceptional electrocatalytic performance, which can be attributed to both the intrinsic activity of Ru sites and the multiple active sites of NiFc-MOF. • Cactus-like Ru@NiFc-MOF composites were synthesized via a two-step solverthermal method. • Ru 0.3 @NiFc-MOF exhibits the excellent performances of HER (η 10 = 25 mV) and OER (η 10 = 210 mV). • The assembled water splitting device only require a voltage of 1.470 V to achieve a current density of 10 mA cm−2. [ABSTRACT FROM AUTHOR]

We describe a method that can be used to produce ruthenium/ruthenium oxide patterns starting from a ruthenium thin film. The method is based on highly localized oxidation of a small surface area of a ruthenium film by means of exposure to a pulsed laser under ambient conditions. Laser exposure is followed by dissolution of the un-exposed ruthenium in a NaClO solution, which leaves the conductive, partially oxidized ruthenium area on the substrate. Spatially selective oxidation, material removal, and, by implication, patterning, are, therefore, achieved without the need for a photoresist layer. Varying the exposure laser parameters, such as fluence, focus diameter, and repetition rate, allows us to optimize the process. In particular, it enables us to obtain circular Ru/RuO2 islands with a sub-diffraction-limited diameter of about 500 nm, for laser exposure times as short as 50 ms. The capability to obtain such small islands suggests that heat-diffusion is not a limiting factor to pattern Ru by laser heating on a (sub-)micron scale. In fact, heat diffusion helps in that it limits the area where a sufficiently high temperature is reached and maintained for a sufficiently long time for oxidation to occur. Our method provides an easy way to produce metallic Ru/RuO2 (sub-)micron structures and has possible applications in semiconductor manufacturing. [ABSTRACT FROM AUTHOR]

A Ruthenium(II) catalyzed additive‐free oxidative, dehydrogenative annulation of different malemides on 3,4‐disubstituted isoquinolone to afford fused and spiro‐cyclized isoquinolo‐isoquinolone and isoindolo‐isoquinolone derivatives is reported here. By simply changing solvent and oxidizing agents, under two different conditions, this methodology produced two different poly‐N‐heterocyclized products. Isoquinolone‐NH was strategically used as the internal directing group in the ortho C−H activation using Ru(II) catalyst. Mechanistically dehydrogenative, oxidative C−C followed by C−N cross‐coupling and aza‐michael reaction pathway led to the corresponding fused and spiro‐products respectively. A diversified library of eighty‐one (81) such two products were synthesized by employing this methodology. The fused and the spirocyclized polyheterocyclic compounds absorbed at λmax 240–270 nm range, however only spiro‐compounds produced blue fluorescence at λem 391–450 nm range. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive structural analysis of the adducts formed upon the reaction of two Ru(III) complexes [HIsq][trans-RuIIICl4(dmso)(Isq)] (1) and [H2Ind][trans-RuIIICl4(dmso)(HInd)] (2) (where HInd-indazole, Isq-isoquinoline, analogs of NAMI-A) and two Ru(II) complexes, cis-[RuCl2(dmso)4] (c) and trans-[RuCl2(dmso)4] (t), with hen-egg white lysozyme (HEWL). Additionally, the crystal structure of an adduct of human lysozyme (HL) with ruthenium complex, [H2Ind][trans-RuCl4(dmso)(HInd)] was solved. X-ray crystallographic data analysis revealed that all studied Ru complexes, regardless of coordination surroundings and metal center charge, coordinate to the same amino acids (His15, Arg14, and Asp101) of HEWL, losing most of their original ligands. In the case of the 2-HL adduct, two distinct metalation sites: (i) Arg107, Arg113 and (ii) Gln127, Gln129, were identified. Crystallographic data were supported by studies of the interaction of 1 and 2 with HEWL in an aqueous solution. Hydrolytic stability studies revealed that both complexes 1 and 2 liberate the N-heterocyclic ligand under crystallization-like conditions (pH 4.5) as well as under physiological pH conditions, and this process is not significantly affected by the presence of HEWL. A comparative examination of nine crystal structures of Ru complexes with lysozyme, obtained through soaking and co-crystallization experiments, together with in-solution studies of the interaction between 1 and 2 with HEWL, indicates that the hydrolytic release of the N-heterocyclic ligand is one of the critical factors in the interaction between Ru complexes and lysozyme. This understanding is crucial in shedding light on the tendency of Ru complexes to target diverse metalation sites during the formation and in the final forms of the adducts with proteins. [ABSTRACT FROM AUTHOR]

The late‐stage functionalization of active pharmaceutical ingredients is a key challenge in medicinal chemistry. Furthermore, N‐aryl triazoles and tetrazoles are important structural motifs with the potential to boost the activity of diverse drug molecules. Using easily accessible dibenzothiophenium salts for the ruthenium‐catalyzed C−H arylation, these scaffolds were introduced into a variety of bioactive compounds. Our methodology uses cost‐efficient ruthenium, KOAc as a mild base and gives access to a plethora of highly decorated triazole and tetrazole containing drug derivatives. [ABSTRACT FROM AUTHOR]

In this work, Ru/WO 3 -O V was obtained through a simple hydrothermal method and low-temperature annealing. The interaction between metal and support induces the directed movement of electrons and protons, optimizing the hydrogen evolution activity of Ru sites. The prepared samples exhibit ultra-high hydrogen evolution activity in the whole pH range and alkaline seawater. [Display omitted] • Ru/WO 3 -O V exhibits ultra-high HER activity across the entire pH range. • Electron/proton transfer boosts Ru site efficiency via WO 3 -O V. • Outstanding alkaline seawater HER activity and practical application potential. The design of electrocatalysts for the hydrogen evolution reaction (HER) that perform effectively across a broad pH spectrum is paramount. The efficiency of hydrogen evolution at ruthenium (Ru) active sites, often hindered by the kinetics of water dissociation in alkaline or neutral conditions, requires further enhancement. Metal oxides, due to superior electron dynamics facilitated by oxygen vacancies (O VS) and shifts in the Fermi level, surpass carbon-based materials. In particular, tungsten oxide (WO 3) promotes the directed migration of electrons and protons which significantly activates the Ru sites. Ru/WO 3 -O V is prepared through a simple hydrothermal and low-temperature annealing process. The prepared catalyst achieves 10 mA cm−2 at overpotentials of 23 mV (1 M KOH), 36 mV (0.5 M H 2 SO 4), 62 mV (1 M PBS), and 38 mV (1 M KOH + seawater). At an overpotential corresponding to 10 mA cm−2 in 1 M KOH and 1 M KOH + seawater, the mass activity of Ru/WO 3 -O V is about 7.7 and 7.86 times that of 20 wt% Pt/C. The improvement in activity and stability arises from electronic modifications attributed to metal-support interaction. This work offers novel insights for modulating the HER activity of Ru sites across a wide pH range. [ABSTRACT FROM AUTHOR]

A new hydroxo‐bridged ruthenium (II) complex [{Ru(η6‐p‐cymene)(iPr2P−O)}2(μ‐OH)]Cl (2) has fortuitously been isolated from the reaction between the known ruthenium(II) complex [RuCl2(η6‐p‐cymene)(iPr2P‐OH)] (1) in either CDCl3 or CHCl3 solutions in the presence of excess DBU (1,8‐diazabicyclo(5.4.0)undec‐7‐ene) at room temperature. Complex 2 is only formed under specific conditions as an orange‐colored air and moisture stable binuclear complex. It is formed via the deprotonation of the P−OH unit in [RuCl2(η6‐p‐cymene)(iPr2P‐OH)]. Complex 2 has been fully characterized by spectroscopic and analytical methods. Its structure was determined by single crystal X‐ray diffraction which reveals a boat‐shaped motif containing a bridging hydroxide unit which undergoes hydrogen bonding with a chloride counterion. Complex 2 was utilized as a catalyst for the hydrogenation of CO2 to formic acid salt using molecular hydrogen. The catalytic reactions were performed at 100 °C in THF in the presence of DBU as a base to isolate [DBU+H][OC(O)H] salt as the final product. Using catalyst loadings down to 0.01 mol%, it was possible to hydrogenate gaseous CO2 with TONs up to 9900. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

This article presents a study on the synthesis of pyrido[1,2-a:4,3-b']diindoles through a ruthenium-catalyzed coupling/cyclization reaction. The researchers investigated the reaction conditions and found that electron-donating groups and certain substitutions on the indole ring were well tolerated, resulting in good yields of the desired products. The proposed reaction pathway involves the formation of a ruthenacycle intermediate, followed by the insertion of a sulfur ylide and subsequent cyclization. The authors suggest that these pyrido[1,2-a:4,3-b']diindole derivatives may have potential pharmaceutical applications. [Extracted from the article]

The first studies on [Ru]‐catalyzed Asymmetric Ring‐Closing Ene‐Yne Metathesis (ARCEYM) are disclosed in this communication. The desymmetrization of achiral ene‐diyne substrates afforded the corresponding exo cyclic compounds in good yields and enantioselectivities (up to 69 % ee). The methodology provided a straightforward access to functionalized scaffolds displaying alkyne and diene useful for further functionalization such as [4+2] cycloaddition reaction. [ABSTRACT FROM AUTHOR]

Photodynamic therapy is an emerging tumor therapy that kills tumor cells by activating reactive oxygen species (ROS) produced by photosensitizers. Mitochondria, as an important organelle, are the main generator of cellular ROS. Therefore, the development of photosensitizers capable of targeting mitochondria could significantly enhance the efficacy of photodynamic therapy. In this study, two novel ruthenium(II) complexes, Ru-1 and Ru-2, were designed and synthesized, both of which were functionalized with α,β-unsaturated ketones for sensing of glutathione (GSH). The crystal structures of the two complexes were determined and they exhibited good recognition of GSH by off–on luminescence signals. The complex Ru-2 containing aromatic naphthalene can enter the cells and react with GSH to generate a strong luminescence signal that can be used to monitor intracellular GSH levels through imaging. Ru-2 also has an excellent mitochondrial localization ability with a Pearson's coefficient of 0.95, which demonstrates that it can efficiently target the mitochondria of tumor cells to enhance the effectiveness of photodynamic therapy as a photosensitizer. [ABSTRACT FROM AUTHOR]

We herein report a method for site‐selective photo‐crosslinking of a DNA duplex. A stilbene pair was introduced into a DNA duplex and a ruthenium complex was conjugated with a triplex‐forming oligonucleotide. We demonstrated that [2+2] photocycloaddition of the stilbene pair occurred upon irradiation with visible light when the ruthenium complex was in close proximity due to triplex formation. No reaction occurred when the ruthenium complex was not in proximity to the stilbene pair. The wavelength of visible light used was of lower energy than the wavelength of UV light necessary for direct excitation of stilbene. Quantum chemical calculation indicated that ruthenium complex catalyzed the photocycloaddition via triplet‐triplet energy transfer. Site selectivity of this photo‐crosslinking system was evaluated using a DNA duplex bearing two stilbene pairs as a substrate; we showed that the site of crosslinking was precisely regulated by the sequence of the oligonucleotide linked to the ruthenium complex. Since this method does not require orthogonal photoresponsive molecules, it will be useful in construction of complex photoresponsive DNA circuits, nanodevices and biological tools. [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]

In this study, Ru complexes [(η6‐p‐cymene)RuX(2‐{(2,6‐iPr2‐C6H3)N=CH}‐C5H3N‐6‐(O))] (3: X=Cl; 4: X=I) were prepared with N‐bound 2‐pyridonato ligand by thermal base‐free MeX elimination from ionic N,N‐chelated Ru complexes [(η6‐p‐cymene)RuX(κ2‐L1)](X) (1: X=Cl; 2: X=I; L1={2‐[(2,6‐iPr2‐C6H3)N=CH]‐6‐(OMe)C5H3N}). The Ru complex 3 was used as O‐donor for Lewis (LA) or Brönsted acids. The reactions of 3 with SnCl2, Ph3SnCl, ZnCl2 or HCl provided [(η6‐p‐cymene)Ru(SnCl3)(2‐{(2,6‐iPr2‐C6H3)N=CH}‐C5H3N‐6‐(O→SnCl2)] (6), [(η6‐p‐cymene)RuCl(2‐{(2,6‐iPr2‐C6H3)N=CH}‐C5H3N‐6‐(O→SnPh3Cl)] (7), and [(η6‐p‐cymene)RuCl(2‐{(2,6‐iPr2‐C6H3)N=CH}‐C5H3N‐6‐(O→)]2(μ‐ZnCl2) (8) and [(η6‐p‐cymene)RuCl(2‐{(2,6‐iPr2‐C6H3)N=CH}‐C5H3N‐6‐(OH)}](Cl) (9). The easy conversion of the 2‐pyridonato ligand in 3 to its 2‐hydroxypyridine in 9 evoked testing of 3 and 4 as potential catalysts in base‐free transfer‐hydrogenation of ketones. [ABSTRACT FROM AUTHOR]

We herein report a method for site‐selective photo‐crosslinking of a DNA duplex. A stilbene pair was introduced into a DNA duplex and a ruthenium complex was conjugated with a triplex‐forming oligonucleotide. We demonstrated that [2+2] photocycloaddition of the stilbene pair occurred upon irradiation with visible light when the ruthenium complex was in close proximity due to triplex formation. No reaction occurred when the ruthenium complex was not in proximity to the stilbene pair. The wavelength of visible light used was of lower energy than the wavelength of UV light necessary for direct excitation of stilbene. Quantum chemical calculation indicated that ruthenium complex catalyzed the photocycloaddition via triplet‐triplet energy transfer. Site selectivity of this photo‐crosslinking system was evaluated using a DNA duplex bearing two stilbene pairs as a substrate; we showed that the site of crosslinking was precisely regulated by the sequence of the oligonucleotide linked to the ruthenium complex. Since this method does not require orthogonal photoresponsive molecules, it will be useful in construction of complex photoresponsive DNA circuits, nanodevices and biological tools. [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]

Abundantly available biomass‐based platform chemicals, including 5‐hydroxymethylfurfural (HMF), are essential stepping stones in steering the chemical industry away from fossil fuels. The efficient catalytic oxidation of HMF to its diacid derivative, 2,5‐furandicarboxylic acid (FDCA), is a promising research area with potential applications in the polymer industry. Currently, the most encouraging approaches are based on solid‐state catalysts and are often conducted in basic aqueous media, conditions where HMF oxidation competes with its decomposition. Efficient molecular catalysts are practically unknown for this reaction. In this study, we report on the synthesis and electrocatalysis of surface‐bound molecular ruthenium complexes for the transformation of HMF to FDCA under acidic conditions. Catalyst immobilisation on mesoporous indium tin oxide electrodes is achieved through the incorporation of phosphonic acid anchoring groups. Screening experiments with HMF and further reaction intermediates revealed the catalytic route and bottlenecks in the catalytic synthesis of FDCA. Utilising these immobilised electrocatalysts, FDCA yields of up to 85 % and faradaic efficiencies of 91 % were achieved, without any indication of substrate decomposition. Surface analysis by X‐ray photoelectron spectroscopy (XPS) post‐electrocatalysis unveiled the desorption of the catalyst from the electrode surface as a limiting factor in terms of catalytic performance. [ABSTRACT FROM AUTHOR]