Journal articles: 'Osmium compounds. Ruthenium compounds. Transition metal complexes'

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Cerón-Camacho, Ricardo, Manuel A. Roque-Ramires, Alexander D. Ryabov, and Ronan Le Lagadec. "Cyclometalated Osmium Compounds and beyond: Synthesis, Properties, Applications." Molecules 26, no. 6 (2021): 1563. http://dx.doi.org/10.3390/molecules26061563.

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The synthesis of cyclometalated osmium complexes is usually more complicated than of other transition metals such as Ni, Pd, Pt, Rh, where cyclometalation reactions readily occur via direct activation of C–H bonds. It differs also from their ruthenium analogs. Cyclometalation for osmium usually occurs under more severe conditions, in polar solvents, using specific precursors, stronger acids, or bases. Such requirements expand reaction mechanisms to electrophilic activation, transmetalation, and oxidative addition, often involving C–H bond activations. Osmacycles exhibit specific applications in homogeneous catalysis, photophysics, bioelectrocatalysis and are studied as anticancer agents. This review describes major synthetic pathways to osmacycles and related compounds and discusses their practical applications.

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Zykova, A. "Synthesis and Structure of Aryl Phosphorus Compounds." Bulletin of the South Ural State University series "Chemistry" 12, no. 4 (2020): 5–50. http://dx.doi.org/10.14529/chem200401.

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Based on an analysis of the literature published from the late 20th century to the beginning of the 21st century, methods for the synthesis of some complex tetraorganylphosphonium salts are systematized and described, along with the features of the chemical transformations of pentaphenylphosphorus, which was first obtained in 1953. The tetraorganylphosphonium salts were known much earlier, however, the features of the synthesis of transition metal complexes, which are usually obtained from tetraorganylphosphorus halides and metal halides, have not been sufficiently studied. The present review is devoted to the discussion of these topics, since the famous Wittig Reaction is associated with aryl phosphorus compounds, which allows synthesizing alkenes of a given structure, and derivatives of transition metals rightfully occupy a special place among catalysts of various chemical processes. The continuation of these classical studies in the field of chemistry of organoelemental compounds takes place at one of the leading universities in Russia - South Ural State University in the laboratory of chemistry of organoelemental compounds at the Faculty of Chemistry. This article aims at familiarizing the reader with the achievements of Professor V.V. Sharutin and his students in the field of organophosphorus compounds. The main attention is paid to the reactions of pentaphenylphosphorus and its derivatives, as well as methods for the synthesis of ionic complexes of silver, gold, copper, titanium, zirconium, hafnium, ruthenium, osmium, cobalt, rhodium, iridium, palladium and platinum with tetraorganylphosphonium cations. The structural features of the described compounds and the possibility of using transition metal complexes in some catalytic reactions are described.

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Aleksanyan, Diana V., Svetlana G. Churusova, Ekaterina Yu Rybalkina, and Vladimir A. Kozlov. "Rhenium(I) Complexes with Pincer Ligands as a New Class of Potential Antitumor Agents." Proceedings 22, no. 1 (2019): 43. http://dx.doi.org/10.3390/proceedings2019022043.

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Transition metal complexes attract continuous research interest as potential antitumor agents. The most popular compounds are ruthenium, gold, titanium, osmium, iridium, zinc, and palladium complexes, which have already displayed cytotoxic features that are not typical for classical platinum-containing chemotherapeutic agents. Substantially lower attention is drawn to organometallic compounds of rhenium. However, the known examples of cytotoxic organometallic rhenium derivatives with bidentate heterocyclic, organophosphorus, labile alkoxide, and hydroxide ligands render further studies in this field very promising. As for their analogs with multidentate ligands, a literature survey has revealed only a few examples of cytotoxic rhenium complexes, whereas the antitumor activity of cyclometallated derivatives has not been studied at all. At the same time, it is known that the use of pincer-type ligands having specific tridentate monoanionic frameworks, which offer multiple options for directed structural modifications, allows one to finely tune the thermodynamic and kinetic stability of the resulting metal complexes. Therefore, we synthesized and studied the cytotoxic properties of a series of rhenium(I) complexes with tridentate pincer-type ligands based on functionalized carboxamides bearing ancillary donor groups both in the acid and amine components. It was shown that the target complexes can be obtained not only by the conventional solution-based method, but also under solvent-free conditions according to the solid-phase methodology recently developed in our group. The results obtained were used to define the main structure–activity relationships for a principally new class of potential antitumor agents and to choose the most promising compounds for further studies in order to create new pharmaceuticals.

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Gianino, Jacqueline, та Seth N. Brown. "Highly covalent metal–ligand π bonding in chelated bis- and tris(iminoxolene) complexes of osmium and ruthenium". Dalton Transactions 49, № 21 (2020): 7015–27. http://dx.doi.org/10.1039/d0dt01287d.

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D’Aléo, A., S. Welter, E. Cecchetto, and L. De Cola. "Electronic energy transfer in dinuclear metal complexes containing meta-substituted phenylene units." Pure and Applied Chemistry 77, no. 6 (2005): 1035–50. http://dx.doi.org/10.1351/pac200577061035.

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The synthesis and photophysical properties of heterometallic dinuclear complexes based on ruthenium and osmium trisbipyridine units, Ru-mPh3-Os and Ru-mPh5-Os, in which the metal complexes are linked via an oligophenylene bridge centrally connected in the meta position, are described. Electronic energy transfer from the excited ruthenium-based component (donor) to the osmium moiety (acceptor) has been investigated using steady-state and time-resolved spectroscopy. The results obtained for the meta-substituted compounds are compared with the analogous systems in which the phenylene spacers are substituted in the para position. The mechanism of energy transfer is discussed.

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Gaiddon, Christian, Isabelle Gross, Xiangjun Meng, et al. "Bypassing the Resistance Mechanisms of the Tumor Ecosystem by Targeting the Endoplasmic Reticulum Stress Pathway Using Ruthenium- and Osmium-Based Organometallic Compounds: An Exciting Long-Term Collaboration with Dr. Michel Pfeffer." Molecules 26, no. 17 (2021): 5386. http://dx.doi.org/10.3390/molecules26175386.

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Metal complexes have been used to treat cancer since the discovery of cisplatin and its interaction with DNA in the 1960’s. Facing the resistance mechanisms against platinum salts and their side effects, safer therapeutic approaches have been sought through other metals, including ruthenium. In the early 2000s, Michel Pfeffer and his collaborators started to investigate the biological activity of organo-ruthenium/osmium complexes, demonstrating their ability to interfere with the activity of purified redox enzymes. Then, they discovered that these organo-ruthenium/osmium complexes could act independently of DNA damage and bypass the requirement for the tumor suppressor gene TP53 to induce the endoplasmic reticulum (ER) stress pathway, which is an original cell death pathway. They showed that other types of ruthenium complexes—as well complexes with other metals (osmium, iron, platinum)—can induce this pathway as well. They also demonstrated that ruthenium complexes accumulate in the ER after entering the cell using passive and active mechanisms. These particular physico-chemical properties of the organometallic complexes designed by Dr. Pfeffer contribute to their ability to reduce tumor growth and angiogenesis. Taken together, the pioneering work of Dr. Michel Pfeffer over his career provides us with a legacy that we have yet to fully embrace.

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Gałczyńska, Katarzyna, Zuzanna Drulis-Kawa, and Michał Arabski. "Antitumor Activity of Pt(II), Ru(III) and Cu(II) Complexes." Molecules 25, no. 15 (2020): 3492. http://dx.doi.org/10.3390/molecules25153492.

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Metal complexes are currently potential therapeutic compounds. The acquisition of resistance by cancer cells or the effective elimination of cancer-affected cells necessitates a constant search for chemical compounds with specific biological activities. One alternative option is the transition metal complexes having potential as antitumor agents. Here, we present the current knowledge about the application of transition metal complexes bearing nickel(II), cobalt(II), copper(II), ruthenium(III), and ruthenium(IV). The cytotoxic properties of the above complexes causing apoptosis, autophagy, DNA damage, and cell cycle inhibition are described in this review.

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Varela, Jesús A., Carlos González-Rodríguez, Silvia G. Rubín, Luis Castedo, and Carlos Saá. "New cyclizations via catalytic ruthenium vinylidenes." Pure and Applied Chemistry 80, no. 5 (2008): 1167–77. http://dx.doi.org/10.1351/pac200880051167.

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New carbocyclizations that proceed via catalytic metal-vinylidenes are presented. Metal-vinylidene catalytic species, which are easily accessible from terminal alkynes and catalytic amounts of transition-metal complexes, can be involved either in pericyclic reactions or in tandem processes triggered by nucleophilic attack at the electrophilic position of the vinylidene. In both cases, a wide variety of valuable cyclic compounds are easily accessible. Some recent carbocyclizations will be described.

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Remita, Hynd, Renée Derai, and Marie-Odile Delcourt. "A new process using radiation for synthesising molecular metal clusters and complexes: First results concerning iron, ruthenium and osmium compounds." International Journal of Radiation Applications and Instrumentation. Part C. Radiation Physics and Chemistry 37, no. 2 (1991): 221–25. http://dx.doi.org/10.1016/1359-0197(91)90132-l.

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Sun, Qi, Yingsi Li, Hongdong Shi, Yi Wang, Jitian Zhang, and Qianling Zhang. "Ruthenium Complexes as Promising Candidates against Lung Cancer." Molecules 26, no. 15 (2021): 4389. http://dx.doi.org/10.3390/molecules26154389.

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Lung cancer is one of the most common malignancies with the highest mortality rate and the second-highest incidence rate after breast cancer, posing a serious threat to human health. The accidental discovery of the antitumor properties of cisplatin in the early 1960s aroused a growing interest in metal-based compounds for cancer treatment. However, the clinical application of cisplatin is limited by serious side effects and drug resistance. Therefore, other transition metal complexes have been developed for the treatment of different malignant cancers. Among them, Ru(II/III)-based complexes have emerged as promising anticancer drug candidates due to their potential anticancer properties and selective cytotoxic activity. In this review, we summarized the latest developments of Ru(II/III) complexes against lung cancer, focusing mainly on the mechanisms of their biological activities, including induction of apoptosis, necroptosis, autophagy, cell cycle arrest, inhibition of cell proliferation, and invasion and metastasis of lung cancer cells.

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Akatsuka, Komi, Ryosuke Abe, Tsugiko Takase, and Dai Oyama. "Coordination Chemistry of Ru(II) Complexes of an Asymmetric Bipyridine Analogue: Synergistic Effects of Supporting Ligand and Coordination Geometry on Reactivities." Molecules 25, no. 1 (2019): 27. http://dx.doi.org/10.3390/molecules25010027.

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The reactivities of transition metal coordination compounds are often controlled by the environment around the coordination sphere. For ruthenium(II) complexes, differences in polypyridyl supporting ligands affect some types of reactivity despite identical coordination geometries. To evaluate the synergistic effects of (i) the supporting ligands, and (ii) the coordination geometry, a series of dicarbonyl–ruthenium(II) complexes that contain both asymmetric and symmetric bidentate polypyridyl ligands were synthesized. Molecular structures of the complexes were determined by X-ray crystallography to distinguish their steric configuration. Structural, computational, and electrochemical analysis revealed some differences between the isomers. Photo- and thermal reactions indicated that the reactivities of the complexes were significantly affected by both their structures and the ligands involved.

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12

Siebert, Ronald, Florian Schlütter, Andreas Winter, et al. "Ruthenium(II)-bis(4′-(4-ethynylphenyl)-2,2′:6′, 2″-terpyridine) — A versatile synthon in supramolecular chemistry. Synthesis and characterization." Open Chemistry 9, no. 6 (2011): 990–99. http://dx.doi.org/10.2478/s11532-011-0087-6.

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AbstractA homoleptic ethynyl-substituted ruthenium(II)-bisterpyridine complex representing a versatile synthon in supramolecular chemistry was synthesized and analyzed by NMR spectroscopy, mass spectrometry and X-ray diffractometry. Furthermore, its photophysical properties were detailed by UV/Vis absorption, emission and resonance Raman spectroscopy. In order to place the results obtained in the context of the vast family of ruthenium coordination compounds, two structurally related complexes were investigated accordingly. These reference compounds bear either no or an increased chromophore in the 4′-position. The spectroscopic investigations reveal a systematic bathochromic shift of the absorption and emission maximum upon increasing chromophore size. This bathochromic shift of the steady state spectra occurs hand in hand with increasing resonance Raman intensities upon excitation of the metal-to-ligand charge-transfer transition. The latter feature is accompanied by an increased excitation delocalization over the chromophore in the 4′-position of the terpyridine. Thus, the results presented allow for a detailed investigation of the electronic effects of the ethynyl substituent on the metal-to-ligand charge-transfer states in the synthon for click reactions leading to coordination polymers.

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Werner, Helmut, Rudolf Weinand, Wolfgang Knaup, Karl Peters, and Hans George Von Schnering. "Vinylidene transition-metal complexes. 18. (Arene)osmium complexes containing alkynyl, vinyl, vinylidene, and thio- and selenoketene units as ligands: a series of organometallic compounds built up from 1-alkynes." Organometallics 10, no. 12 (1991): 3967–77. http://dx.doi.org/10.1021/om00058a010.

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Bilel, Hallouma, Rawdha Medyouni, A. S. Al-Ayed, Naceur Hamdi, Cédric Fischmeister, and Christian Bruneau. "Synthesis of Bioactives Coumarin Derivatives, Phthalocyanines and Terminal Conjugated Dienes via a Ruthenium Catalyzed Cross-Metathesis: Application to Renewable Resources." Materials Science Forum 842 (February 2016): 1–45. http://dx.doi.org/10.4028/www.scientific.net/msf.842.1.

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This study aimed for the synthesis of 4-Aryl-2-amino-6-(4-hydroxy coumarin-3-yl) pyridine-3-carbonitriles derivatives 4, suitable for use as antibacterial, anti-oxidant and anti-inflammatory activities via a versatile, readily accessible 3-((2E)-3(aryl)prop-2-enoyl)-2H-chromen-2-one, 3, which was prepared by refluxing 3-acetyl-4-hydroxycoumarin with aromatic aldehydes in chloroform in the presence of a catalytic amount of piperidine. Then the direct reaction of the obtained chalcones 3 with malonitrile in the presence of ammonium acetate in one step gave products 4. Most of the new compound 4 exhibit moderate antibacterial activity against Gram Negative bacterial strains (E. coli, K. pneumonia, S. typhi and S. flexneri). In addition, the compounds 4 were investigated for anti-oxidant activities by super oxide radical, DPPH (2,2-Diphenyl-1-picrylhydrazyl), and hydroxyl radical scavenging assays, where most of the compounds displayed significant antioxidant activities. Furthermore, these 4-Aryl-2-amino-6-(4-hydroxy coumarin-3-yl) pyridine-3-carbonitriles 4 were evaluated for anti-inflammatory activity by indirect haemolytic and lipoxygenase inhibition assays where compounds revealed good activity. The preparation of novel metal-free phthalocyanines and metallophthalocyanine complexes 11 and 12 (MPcs, M = Co, Zn, Cu and Mn), with four peripheral 6-hydroxy-4-methylcoumarin and 6-hydroxycoumarin substituents, were also prepared by cyclotetramerization of compounds 7 and 10 with the corresponding metal salts (Zn(OAc)2.2H2O, Co(OAc)2.4H2O, CuCl, Mn(OAc)2.4H2O) as a template for macrocycle formation in 2-(N,N-dimethylamino)ethanol.The electronic spectra of these compounds exhibit a band of coumarin identity together with characteristic bands of the phthalocyanine core. The new compounds were screened for antibacterial activity. Most of them are active against E. coli and S. aureus. In addition, some novel 3-acetylcoumarin derivatives 17 were prepared in good yields. Their invitro antioxidant activities were assayed by the quantitative 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity method. In this way, novel coumarin phtalonitriles derivatives 42-44 were synthesized.The synthesis of these coumarin phtalonitriles was resulting from a nucleophilic aromatic substitution reaction between 4-nitrophtalonitrile and coumarins derivatives. The complexing properties of the coumarin derivatives toward alkali metal, alkaline earth metal, some transition metals and some heavy metal cations have been investigated in acetonitrile by means of UV spectrophotometry absorption and conductivity methods. Thus, the stoichiometry of the complexes formed and their stability constants were determined. We report also in this book chapter a sequence of two ruthenium-catalyzed transformations, namely olefin cross metathesis with allylic chloride followed by elimination, which gives a straightforward access to terminal 1,3-dienes from natural products. The structures of all the new obtained compounds were confirmed by elemental analysis, IR, and multinuclear/multidimensional NMR spectroscopy (1H, 13C-NMR, NOESY, HMBC) which allowed assignment of the complete network of proton and carbon atoms).

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Ryabov, Alexander D. "The Exchange of Cyclometalated Ligands." Molecules 26, no. 1 (2021): 210. http://dx.doi.org/10.3390/molecules26010210.

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Reactions of cyclometalated compounds are numerous. This account is focused on one of such reactions, the exchange of cyclometalated ligands, a reaction between a cyclometalated compound and an incoming ligand that replaces a previously cyclometalated ligand to form a new metalacycle: + H-C*~Z ⇄ + H-C~Y. Originally discovered for PdII complexes with Y/Z = N, P, S, the exchange appeared to be a mechanistically challenging, simple, and convenient routine for the synthesis of cyclopalladated complexes. Over four decades it was expanded to cyclometalated derivatives of platinum, ruthenium, manganese, rhodium, and iridium. The exchange, which is also questionably referred to as transcyclometalation, offers attractive synthetic possibilities and assists in disclosing key mechanistic pathways associated with the C–H bond activation by transition metal complexes and C–M bond cleavage. Both synthetic and mechanistic aspects of the exchange are reviewed and discussed.

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Masternak, Joanna, Agnieszka Gilewska, Barbara Barszcz, et al. "Ruthenium(II) and Iridium(III) Complexes as Tested Materials for New Anticancer Agents." Materials 13, no. 16 (2020): 3491. http://dx.doi.org/10.3390/ma13163491.

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The oncological use of cisplatin is hindered by its severe side effects and a very important resistance problem. To overcome these problems, scientists have attempted to design new generation transition-metal anticancer complexes. In this study, we present new complexes, ruthenium(II) [(η6-p-cymene)RuCl(py2CO)]PF6 (1), iridium(III) [(η5-Cp)IrCl(py2CO)]PF6 (2), and NH4[IrCl4(py2CO)]·H2O (3), based on di-2-pyridylketone (py2CO). The prepared complexes were characterized by FTIR, 1H, 13C, 15N NMR, UV-Vis, PL and elemental analysis techniques. The single-crystal X-ray structure analysis and comparative data revealed pseudo-octahedral half-sandwich 1 and 2 complexes and octahedral tetrachloroiridate(III) 3 with a rare chelating κ2N,O coordination mode of py2CO. The compounds were tested in vitro against three cancer cell lines—colorectal adenoma (LoVo), myelomonocytic leukaemia (MV-4-11), breast adenocarcinoma (MCF-7), and normal fibroblasts (BALB/3T3). The most promising results were obtained for iridium(III) complex 3 against MV-4-11 (IC50 = 35.8 ± 13.9 µg/mL) without a toxic effect against normal BALB/3T3, which pointed towards its selectivity as a potential anticancer agent. Extensive research into their mode of binding with DNA confirmed for 1 and 2 complexes non-classical binding modes, while the 3D circular dichroism (CD) experiment (ΔTm) suggested that 3 induced the probable formation of covalent bonds with DNA. In addition, the obtained iridium complexes induce ROS, which, in synergy with hydrolysis promoting DNA bonding, may lead to cancer cell death.

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Khalimon, Andrey, Kristina Gudun, and Davit Hayrapetyan. "Base Metal Catalysts for Deoxygenative Reduction of Amides to Amines." Catalysts 9, no. 6 (2019): 490. http://dx.doi.org/10.3390/catal9060490.

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The development of efficient methodologies for production of amines attracts significant attention from synthetic chemists, because amines serve as essential building blocks in the synthesis of many pharmaceuticals, natural products, and agrochemicals. In this regard, deoxygenative reduction of amides to amines by means of transition-metal-catalyzed hydrogenation, hydrosilylation, and hydroboration reactions represents an attractive alternative to conventional wasteful techniques based on stoichiometric reductions of the corresponding amides and imines, and reductive amination of aldehydes with metal hydride reagents. The relatively low electrophilicity of the amide carbonyl group makes this transformation more challenging compared to reduction of other carbonyl compounds, and the majority of the reported catalytic systems employ precious metals such as platinum, rhodium, iridium, and ruthenium. Despite the application of more abundant and environmentally benign base metal (Mn, Fe, Co, and Ni) complexes for deoxygenative reduction of amides have been developed to a lesser extent, such catalytic systems are of great importance. This review is focused on the current achievements in the base-metal-catalyzed deoxygenative hydrogenation, hydrosilylation, and hydroboration of amides to amines. Special attention is paid to the design of base metal catalysts and the mechanisms of such catalytic transformations.

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Braun, T., P. Steinert, and H. Werner. "Vinylidene transition metal complexes XXXIV the preparation and structure of neutral vinylidene and allenylidene ruthenium(II) compounds of the half-sandwich type containing iPr2PCH2CO2Me as supporting ligand." Journal of Organometallic Chemistry 488, no. 1-2 (1995): 169–76. http://dx.doi.org/10.1016/0022-328x(94)00015-5.

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Summers, Kelly L. "A Structural Chemistry Perspective on the Antimalarial Properties of Thiosemicarbazone Metal Complexes." Mini-Reviews in Medicinal Chemistry 19, no. 7 (2019): 569–90. http://dx.doi.org/10.2174/1389557518666181015152657.

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Malaria is a potentially life-threatening disease, affecting approx. 214 million people worldwide. Malaria is caused by a protozoan, Plasmodium falciparum, which is transmitted through the Anopheles mosquito. Malaria treatment is becoming more challenging due to rising resistance against the antimalarial drug, chloroquine. Novel compounds that target aspects of parasite development are being explored in attempts to overcome this wide-spread problem. Anti-malarial drugs target specific aspects of parasite growth and development within the human host. One of the most effective targets is the inhibition of hematin formation, either through inhibition of cysteine proteases or through iron chelation. Metal-thiosemicarbazone (TSC) complexes have been tested for antimalarial efficacy against drug-sensitive and drug-resistant strains of P. falciparum. An array of TSC complexes with numerous transition metals, including ruthenium, palladium, and gold has displayed antiplasmodial activity. Au(I)- and Pd(II)-TSC complexes displayed the greatest potency; 4-amino-7-chloroquine moieties were also found to improve antiplasmodial activity of TSCs. Although promising metal-TSC drug candidates have been tested against laboratory strains of P. falciparum, problems arise when attempting to compare between studies. Future work should strive to completely characterize synthesized metal-TSC structures and assess antiplasmodial potency against several drug-sensitive and drugresistant strains. Future studies need to precisely determine IC50 values for antimalarial drugs, chloroquine and ferroquine, to establish accurate standard values. This will make future comparisons across studies more feasible and potentially help reveal structure-function relationships. Investigations that attempt to link drug structures or properties to antiplasmodial mechanism(s) of action will aid in the design of antimalarial drugs that may combat rising drug resistance.

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Bayrakdarian, Malken, Martin J. Davis, Christian Reber, and Davit Zargarian. "Absorption spectroscopy of (Ind)Ni(PPh3)X (Ind = indenyl, 1-Me-indenyl; X = Cl, Br, Me) and M(Ind)2 (M = Ni, Ru; Ind = indenyl)." Canadian Journal of Chemistry 74, no. 11 (1996): 2194–200. http://dx.doi.org/10.1139/v96-246.

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The electronic structures of two types of transition metal indenyl complexes have been studied. The first type, a series of (Ind)Ni(PPh3)X compounds (Ind = indenyl, 1-Me-indenyl; X = Cl, Br, Me) was investigated by absorption spectroscopy and Extended Hückel Molecular Orbital calculations. The energy differences between calculated levels are in good agreement with experimental band positions. For example, the lowest energy singlet–singlet band maximum for (Ind)Ni(PPh3)Cl is at 19 500 cm−1 and the calculated HOMO–LUMO difference is 19 817 cm−1. For X = Me, the calculated energy difference increases to 21 930 cm−1 and the corresponding absorption band is at 22 500 cm−1. The influence of the metal–ligand interactions on the molecular orbitals is discussed. The second category of indenyls, the bis(indenyl) compounds of Ni and Ru, show absorption spectra that are markedly different from those of nickelocene and ruthenocene. For example, in comparison to nickelocene, the first absorption band of Ni(Ind)2 is 5700 cm−1 higher in energy and is more intense by two orders of magnitude; in contrast, the first absorption maximum of Ru(Ind)2 is 6600 cm−1 lower in energy than observed for ruthenocene. The characteristics and relaxation dynamics of the lowest energy excited states are discussed. Key words: absorption spectroscopy, indenyl, nickel, ruthenium, EHMO analysis.

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Kaim, Wolfgang, Natasa Doslik, Stephanie Frantz, et al. "Azo compounds as electron acceptor or radical ligands in transition metal species: spectroelectrochemistry and high-field EPR studies of ruthenium, rhodium and copper complexes of 2,2′-azobis(5-chloropyrimidine)." Journal of Molecular Structure 656, no. 1-3 (2003): 183–94. http://dx.doi.org/10.1016/s0022-2860(03)00339-9.

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Sellmann, Dieter, and Michael Waeber. "Übergangsmetallkomplexe mit Schwefelliganden, XVIII. Synthese und Reaktionen von [Ru(L)(PPh3)dttd]-Komplexen mit kleinen Stickstoffverbindungen L = NH3, N2H4, N2H3CH3, N2H3C6H5 sowie NO+ (dttd2- = 2,3;8,9-Dibenzo-1,4,7,10-tetrathiadecan (–2))/ Transition Metal Complexes with Sulfur Ligands, XVIII. Synthesis and Reactions of [Ru(L)(PPh3)dttd] Complexes with Small Nitrogen Compounds L = NH3, N2H4, N2H3CH3, N2H3C6H5 and NO+ (dttd2- = 2,3;8,9-Dibenzo-1,4,7,10-tetrathiadecane (–2))." Zeitschrift für Naturforschung B 41, no. 7 (1986): 877–84. http://dx.doi.org/10.1515/znb-1986-0714.

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Abstract Reaktionen von [Ru(L)(PPh3)dttd]-Komplexen mit kleinen Stickstoffverbindungen L = NH3, N2H4, N2H3CH3, N2H3C6H5 sowie NO+ (dttd2-= 2,3;8,9-Dibenzo-l,4,7,10-tetrathiadecan (—2)) Transition Metal Complexes with Sulfur Ligands, XVIII* Synthesis and Reactions of [R u(L)(PPh3)dttd] Complexes with Small Nitrogen Com pounds L = N H 3, N2H 4, N2H 3C H 3, N2H 3C6H 5 and N O + (dttd2-= 2,3;8,9-D ibenzo-l,4,7,10-tetrathiadecane (—2)) D ieter Sellmann+ Ruthenium Sulfur C om plexes, N itrogen Ligands The com plex fragment [Ru(PPh3)dttd], (dttd2-= 2,3;8,9-dibenzo-l,4,7,10-tetrath iad ecane (— 2)), coordinates small nitrogen com pounds, which have only o-as well as a-jr-donor proper ties. The reactions o f [Ru(PPh3)2dttd] with L — N H 3, N 2H 4, N 2H 3C H 3 and N 2H 3C6H 5, respec tively, give the corresponding [R u(L)(PP h3)dttd] com plexes. O xidation o f the hydrazine com plex [R u(N 2H 4)(PPh3)dttd] yields [a-N 2H 2{R u(PP h3)dttd }2], the first diazene com plex in which the unstable N 2H 2 is bound to a sulfur coordinated m etal center and stabilized by a 4 c —6 e Ru— N — N — Ru system , steric shielding as well as thiolate — S---H (n,h2)---N hydrogen bridges. The reactions of the ammonia and the hydrazine com plexes, respectively, with N O PF6 yield the nitrosyl com plex [R u (N O)(PP h3)dttd]PF6 as final product; in the case o f [R u(N 2H 4)(P P h3)dttd] the intermediate formation of an azido com plex is observed IR -spectroscopically.

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Durran, Sean E., Martin B. Smith, Alexandra MZ Slawin, Thomas Gelbrich, Michael B. Hursthouse, and Mark E. Light. "Synthesis and coordination studies of new aminoalcohol functionalized tertiary phosphines." Canadian Journal of Chemistry 79, no. 5-6 (2001): 780–91. http://dx.doi.org/10.1139/v01-037.

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The synthesis of two new aminoalcohol functionalized tertiary phosphines o-Ph2PCH2N(H)C6H4(OH) (I) and o-Ph2PCH2N(H)C6H4(CH2OH) (II) are reported. Oxidation with aqueous H2O2 gave the corresponding phosphine oxides o-Ph2P(O)CH2N(H)C6H4(OH) (III) and o-Ph2P(O)CH2N(H)C6H4(CH2OH) (IV) (31P NMR evidence only). The ligating ability of I, II and, in several cases, the known ligand 2,3-Ph2PCH2N(H)C5H3N(OH) (V), was investigated with a range of late transition-metal precursors. Accordingly, reaction of 2 equiv of I (or II) with [MCl2(cod)] (M = Pd or Pt, cod = cycloocta-1,5-diene) gave the corresponding dichloro metal(II) complexes [MCl2(I)2] (M = Pd 1; M = Pt 2) and [MCl2(II)2] (M = Pd 3; M = Pt 4) in which I (and II) P-coordinate. Solution NMR studies reveal that 2 and 4 are exclusively cis whereas 1 and 3 are present as a mixture of cis and (or) trans isomers [4.7:1 (for 1); 2.2:1 (for 3)]. Reaction of 2 equiv of II with [Pt(CH3)2(cod)] gave the neutral complex [Pt(CH3)2(II)2] (5) whose X-ray structure confirmed a cis disposition of "hybrid" ligands. In contrast, reaction of I with [Pt(CH3)2(cod)] gave initially [Pt(CH3)2(I)2] (6) which, upon standing, afforded several products possibly reflecting an increased acidity of the phenolic groups of ligated I. Chloro bridge cleavage reactions of [{Ru(µ-Cl)Cl(p-cymene)}2] or [{Rh(µ-Cl)Cl{C5(CH3)5}}2] with I (or II) proceeds smoothly and gave the mononuclear complexes [RuCl2(p-cymene)I] (7), [RuCl2(p-cymene)II] (8), [RhCl2{C5(CH3)5}I] (9), and [RhCl2{C5(CH3)5}II] (10) in good yield. X-ray crystallography confirms both ruthenium complexes bear P-coordinated I (or II) ligands. Molecules of 7 are linked into linear chains via O-H···Clcoord intermolecular hydrogen bonding, a feature absent in the closely related compound 8. Reaction of [AuCl(tht)] (tht = tetrahydrothiophene) with 1 equiv of I (or II) gave the corresponding gold(I) complexes [AuCl(I)] (11) and [AuCl(II)] (12). Bridge cleavage of the cyclometallated palladium(II) dimers [{Pd(µ-Cl)(C~N)}2] [C~N = C,N-C6H4CH2N(CH3)2, C,N-C10H6N(CH3)2, C,N-C6H4N=NC6H5] with V (or I) gave the neutral complexes [PdCl(C~N)V] (13-15) (or [PdCl(C9H12N)I] (16)), respectively. Chloride abstraction from 13 (or 15) with Ag[BF4] gave the cationic complexes [Pd(C~N)V][BF4] (17) (or 18) in which V P,N pyridyl-chelates to the palladium(II) metal centre. The X-ray structures of 13 and 18 have been determined and confirm the expected coordination environments. An array of intra- and intermolecular H-bonding contacts are also observed. All compounds have been characterized by a combination of spectroscopic and analytical studies.Key words: phosphines, crystal structures, alcohols, precious metals.

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Sellmann, Dieter, Olaf Käppler, Falk Knoch та Matthias Moll. "Übergangsmetallkomplexe mit Schwefelliganden, XLIX Außergewöhnliche Säure-Basenreaktionen an niedervalenten Ru-Nitrosyl-Komplexen mit dem Thiolat-amin-Liganden ′S2Ν2Ηχ'2- (χ = 1, 2) und Mo-Komplexe mit den Liganden′S2N2H2′2- und ′buS2N2H2′ 2-, Synthese, Struktur und Reaktionen / Transition Metal Complexes with Sulfur Ligands, XLIX Unusual Acid Base Reactions of Low Valence Ruthenium Nitrosyl Complexes with the Thiolate-amine Ligands ′S2Ν2ΗΧ'2- (χ = 1, 2) and Molybdenum Complexes with the Ligands ′S2N2H2′ 2- and ′buS2N2H2′ 2-, Syntheses, Structure and Reactions". Zeitschrift für Naturforschung B 45, № 6 (1990): 803–16. http://dx.doi.org/10.1515/znb-1990-0612.

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In order to find complexes suited as model compounds for oxidoreductases catalyzing reactions of the biological nitrogen cycle, Ru- and Mo-nitrosyl complexes with the ′S2N2H2'2- and ′buS2N2H2′ 2--** ligand were synthesized. The reaction of [Ru(NO)(PPh3)2Cl3] with Li2-'S2N2H2' yields the binuclear [Ru(NO)(′S2N2H′)]2 (1) and the mononuclear [Ru(NO)(PPh3)(′S2N2H2′ )]Cl (2). Formation of 1 is explained by HCl and subsequent PPh3 elimination from 2; the coordinatively unsaturated [Ru(NO)(′S2N2H′)] dimerize to give 1. 1 is also obtained a) when [Ru(NO)2(PPh3)2] is reacted with Li2-'S2N2H2′ , b) when 2 is treated with bases, e.g. N2H4, or c) when [Ru(NO)Cl(′S2N2H2′ )] is attempted to be recrystallized from DMSO or THF/MeOH. The very labile [Ru(NO)Cl(′S2N2H2′ )] (5) forms when Ru(NO)Cl3 · 3 H2O is reacted with Na2—'S2N2H2′. The structures of 1 and 2 were determined by X-ray diffraction. They show sixcoordinate RuII centers with the thiolate S atoms in cis positions. The mononuclear complexes [Ru(NO)(PMePh2)(′S2N2H′)] (3) and [Ru(NO)(PMe3)(′S2N2H′)] (4) were obtained by cleavage of 1 with PMePh2 or PMe3, respectively. The formally 14e configurated molybdenum chloro complexes [MoCl2(′S2N2H2′ )] (6) and [MoCl2(′buS2N2H2′ )] (7) were obtained from the reaction of [MoCl4(THF)2] with ′S2N2H2′ 2- and yields the cis configurated [Mo(NO)2(′S2N2H2′ )] (8) and [Mo(NO)2(′buS2N2H2′ )] (9) respectively. 9 is also obtained from the reaction of [Mo(NO)2Cl2] with ′buH2S2N2H2′ . [Mo(NO)Cl3(CH3CN)2] and Na2-'S2N2H2′ react to give the MoIII complex [Mo(NO)Cl(′S2N2H2′ )] (10).

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Traub, Lukas, and Oliver Reiser. "Homogeneous visible light mediated transition metal catalysis other than Ruthenium and Iridium." Physical Sciences Reviews 4, no. 7 (2019). http://dx.doi.org/10.1515/psr-2017-0172.

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Abstract The field of photoredox chemistry is dominated by ruthenium- or iridium based metal complexes or organic dyes that are employed as catalysts. Other metal based coordination compounds provide a cost efficient alternative, however, the much shorter excited lifetimes generally observed for such complexes make their application more challenging. Nevertheless, a growing number of successful examples with metal complexes based on chromium, iron, nickel, zirconium, cerium, rhenium, platinum, uranium, and especially on copper exist, which is being reviewed in this chapter.

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SCHAAL, M., W. WEIGAND, U. NAGEL та W. BECK. "ChemInform Abstract: PSEUDOHALO METAL COMPOUNDS. LXIV. REACTIONS OF CYANO COMPLEXES OF IRON(II), RUTHENIUM(II), OSMIUM(II), AND PLATINUM(II) WITH α,β-UNSATURATED CARBONYL COMPOUNDS OR KETONES IN THE PRESENCE OF ACIDS: Γ-OXOISOCYANIDE COMPLEXES. X-RAY STRU". Chemischer Informationsdienst 16, № 40 (1985). http://dx.doi.org/10.1002/chin.198540316.

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Ricciardi, Loredana, and Massimo La Deda. "Recent advances in cancer photo-theranostics: the synergistic combination of transition metal complexes and gold nanostructures." SN Applied Sciences 3, no. 3 (2021). http://dx.doi.org/10.1007/s42452-021-04329-6.

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AbstractIn this mini review, we highlight advances in the last five years in light-activated cancer theranostics by using hybrid systems consisting of transition metal complexes (TMCs) and plasmonic gold nanostructures (AuNPs). TMCs are molecules with attractive properties and high potential in biomedical application. Due to their antiproliferative abilities, platinum-based compounds are currently first-choice drugs for the treatment of several solid tumors. Moreover, ruthenium, iridium and platinum complexes are well-known for their ability to photogenerate singlet oxygen, a highly cytotoxic reactive species with a key role in photodynamic therapy. Their potential is further extended by the unique photophysical properties, which make TMCs particularly suitable for bioimaging. Recently, gold nanoparticles (AuNPs) have been widely investigated as one of the leading nanomaterials in cancer theranostics. AuNPs—being an inert and highly biocompatible material—represent excellent drug delivery systems, overcoming most of the side effects associated with the systemic administration of anticancer drugs. Furthermore, due to the thermoplasmonic properties, AuNPs proved to be efficient nano-sources of heat for photothermal therapy application. Therefore, the hybrid combination TMC/AuNPs could represent a synergistic merger of multiple functionalities for combinatorial cancer therapy strategies. Herein, we report the most recent examples of TMC/AuNPs systems in in-vitro in-vivo cancer tharanostics application whose effects are triggered by light-exposure in the Vis–NIR region, leading to a spatial and temporal control of the TMC/AuNPs activation for light-mediated precision therapeutics.

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Journal articles on the topic 'Osmium compounds. Ruthenium compounds. Transition metal complexes'

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