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Journal articles on the topic 'Metal complexes. Ruthenium. Iron'

Author: Grafiati

Published: 4 June 2021

Last updated: 15 February 2022

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1

Kim, Junhwan, and Malcolm E. Kenney. "The synthesis and properties of iron, ruthenium, and osmium octabutoxynaphthalocyanine." Journal of Porphyrins and Phthalocyanines 16, no. 09 (September 2012): 1068–71. http://dx.doi.org/10.1142/s1088424612500903.

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New series of iron, ruthenium, and osmium octabutoxynaphthalocyanines were synthesized by inserting corresponding metals into the metal-free octabutoxynaphthalocyanine. Although preparation of axial ligand-free iron octabutoxynaphthalocyanines was reported before, we could not reproduce the synthesis by following the reported method. We attributed the failure to the instability of the iron octabutoxynaphthalocyanines. Bis-ligation increased the stability of the iron complex but only sufficiently for characterization. The application of iron complexes will be limited by their instability. However, ruthenium and osmium formed stable complexes with this macrocycle ring but with significantly lower reaction yields. These new complexes were characterized by NMR, UV-vis, and mass spectrometry.

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2

Gaiddon, Christian, Isabelle Gross, Xiangjun Meng, Marjorie Sidhoum, Georg Mellitzer, Benoit Romain, Jean-Batiste Delhorme, Aïna Venkatasamy, Alain C. Jung, and Michel Pfeffer. "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 (September 4, 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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3

Wang, Hai-Xu, Qingyun Wan, Kam-Hung Low, Cong-Ying Zhou, Jie-Sheng Huang, Jun-Long Zhang, and Chi-Ming Che. "Stable group 8 metal porphyrin mono- and bis(dialkylcarbene) complexes: synthesis, characterization, and catalytic activity." Chemical Science 11, no. 8 (2020): 2243–59. http://dx.doi.org/10.1039/c9sc05432d.

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We report the isolation, X-ray crystal structures, reactivity and DFT calculations of iron- and ruthenium-mono(dialkylcarbene) and osmium-bis(dialkylcarbene) porphyrins and diarylcarbene transfer/insertion reactions catalyzed by iron-mono(dialkylcarbene) porphyrin.

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4

Poursharifi, Mina, Marek T. Wlodarczyk, and Aneta J. Mieszawska. "Nano-Based Systems and Biomacromolecules as Carriers for Metallodrugs in Anticancer Therapy." Inorganics 7, no. 1 (December 20, 2018): 2. http://dx.doi.org/10.3390/inorganics7010002.

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Since the discovery of cisplatin and its potency in anticancer therapy, the development of metallodrugs has been an active area of research. The large choice of transition metals, oxidation states, coordinating ligands, and different geometries, allows for the design of metal-based agents with unique mechanisms of action. Many metallodrugs, such as titanium, ruthenium, gallium, tin, gold, and copper-based complexes have been found to have anticancer activities. However, biological application of these agents necessitates aqueous solubility and low systemic toxicity. This minireview highlights the emerging strategies to facilitate the in vivo application of metallodrugs, aimed at enhancing their solubility and bioavailability, as well as improving their delivery to tumor tissues. The focus is on encapsulating the metal-based complexes into nanocarriers or coupling to biomacromolecules, generating efficacious anticancer therapies. The delivery systems for complexes of platinum, ruthenium, copper, and iron are discussed with most recent examples.

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5

Murahashi, Shun-Ichi, Naruyoshi Komiya, Yukiko Hayashi, and Tatsuyuki Kumano. "Copper complexes for catalytic, aerobic oxidation of hydrocarbons." Pure and Applied Chemistry 73, no. 2 (January 1, 2001): 311–14. http://dx.doi.org/10.1351/pac200173020311.

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Catalytic oxidation of hydrocarbons can be performed efficiently upon treatment with tert-butylhydroperoxide or peracetic acid in the presence of a low-valent ruthenium catalyst. Furthermore, aerobic oxidation of hydrocarbons can be performed in the presence of acetaldehyde using ruthenium, iron, and copper catalysts. Copper derived from copper chloride/crown ether or copper chloride/crown ether/alkaline metal salts have proved to be efficient catalysts. Further study revealed that specific copper complexes formed from copper salts and acetonitrile are convenient and highly useful catalysts for the aerobic oxidation of unactivated hydrocarbons.

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6

Ford, Peter C. "Photochemical reactions of metal nitrosyl complexes. Mechanisms of NO reactions with biologically relevant metal centers." International Journal of Photoenergy 3, no. 3 (2001): 161–69. http://dx.doi.org/10.1155/s1110662x01000204.

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The discoveries that nitric oxide (a.k.a. nitrogen monoxide) serves important roles in mammalian bioregulation and immunology have stimulated intense interest in the chemistry and biochemistry of NO and derivatives such as metal nitrosyl complexes. Also of interest are strategies to deliver NO to biological targets on demand. One such strategy would be to employ a precursor which displays relatively low thermal reactivity but is photochemically active to release NO. This proposition led us to investigate laser flash and continuous photolysis kinetics of nitrosyl complexes such as the Roussin's iron-sulfur-nitrosyl cluster anionsFe2S2(NO)42−andFe4S3(NO)7−and several ruthenium salen and porphyrin nitrosyls. These include studies using metal-nitrosyl photochemistry as a vehicle for delivering NO to hypoxic cell cultures in order to sensitizeγ-radiation damage. Also studied were the rates and mechanisms of NO “on” reactions with model water soluble heme compounds, the ferriheme protein met-myoglobin and various ruthenium complexes using ns laser flash photolysis techniques. An overview of these studies is presented.

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7

Rocha, Reginaldo C., and Henrique E. Toma. "Intervalence transfer in a new benzotriazolate bridged ruthenium-iron complex." Canadian Journal of Chemistry 79, no. 2 (February 1, 2001): 145–56. http://dx.doi.org/10.1139/v00-195.

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The unsymmetrical dinuclear rutheniumiron complexes [(NH3)5RubtaFe(CN)5]n (where bta = benzotriazolate; n = 2, 1, 0) were prepared as solid sodium salts from [RuII(NH3)5(bta)]+ or [RuIII(NH3)5(bta)]2+ and [FeII(CN)5(H2O)]3 and characterized in aqueous solution by means of electrochemical and spectroelectrochemical methods. UV-vis, near-infrared, IR, and cyclic and differential pulse voltammetry data suggest that the related mixed valent species belong to a valence trapped formulation, featuring localized Ru(III) and Fe(II) oxidation states. In spite of the class II categorization in the Robin and Day scheme, this system shows a remarkable metalmetal electronic coupling, as deduced from an intense, low-energy, and very broad intervalence band in the near-IR region. In addition, the mixed valence state displays enhanced stabilization in relation to the isovalent state. The intervalence transfer properties are discussed on the basis of Hush's theory.Key words: ammineruthenium complexes, cyanoiron complexes, mixed valence, intervalence, benzotriazole, benzotriazolate.

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8

Prasad, Sahdeo, Dan DuBourdieu, Ajay Srivastava, Prafulla Kumar, and Rajiv Lall. "Metal–Curcumin Complexes in Therapeutics: An Approach to Enhance Pharmacological Effects of Curcumin." International Journal of Molecular Sciences 22, no. 13 (June 30, 2021): 7094. http://dx.doi.org/10.3390/ijms22137094.

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Curcumin, an active component of the rhizome turmeric, has gained much attention as a plant-based compound with pleiotropic pharmacological properties. It possesses anti-inflammatory, antioxidant, hypoglycemic, antimicrobial, neuroprotective, and immunomodulatory activities. However, the health-promoting utility of curcumin is constrained due to its hydrophobic nature, water insolubility, poor bioavailability, rapid metabolism, and systemic elimination. Therefore, an innovative stride was taken, and complexes of metals with curcumin have been synthesized. Curcumin usually reacts with metals through the β-diketone moiety to generate metal–curcumin complexes. It is well established that curcumin strongly chelates several metal ions, including boron, cobalt, copper, gallium, gadolinium, gold, lanthanum, manganese, nickel, iron, palladium, platinum, ruthenium, silver, vanadium, and zinc. In this review, the pharmacological, chemopreventive, and therapeutic activities of metal–curcumin complexes are discussed. Metal–curcumin complexes increase the solubility, cellular uptake, and bioavailability and improve the antioxidant, anti-inflammatory, antimicrobial, and antiviral effects of curcumin. Metal–curcumin complexes have also demonstrated efficacy against various chronic diseases, including cancer, arthritis, osteoporosis, and neurological disorders such as Alzheimer’s disease. These biological activities of metal–curcumin complexes were associated with the modulation of inflammatory mediators, transcription factors, protein kinases, antiapoptotic proteins, lipid peroxidation, and antioxidant enzymes. In addition, metal–curcumin complexes have shown usefulness in biological imaging and radioimaging. The future use of metal–curcumin complexes may represent a new approach in the prevention and treatment of chronic diseases.

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9

Swamy, S. J., B. Veera Pratap, P. Someshwar, K. Suresh, and D. Nagaraju. "Synthesis and Spectral Studies of Iron(III), Ruthenium(III) and Rhodium(III) Complexes with New Tetraaza Macrocyclic Ligands." Journal of Chemical Research 2005, no. 5 (May 2005): 313–15. http://dx.doi.org/10.3184/0308234054323986.

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Complexes of iron(III), ruthenium(III) and rhodium(III) with three new tetraaza macrocyclic ligands, oxo4bzo3[14]triene-N4 [TBTAC14Tone], oxo4bzo2[14]diene-N4 [DBTAC14Tone] and oxo4bzo2[15]diene-N4 [DBTAC15Tone] have been prepared and characterised. The complexes are found to have the formulae [FeLCl2]Cl. 2H2O, [RuLCl2]Cl. 3H2O and [RhLCl2]Cl. 2H2O. The cations adopt a trans-dichloro configuration with the six-coordinated trivalent metal ions in a pseudo-octahedral geometry.

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10

KIENAST, ARNE, LUTZ GALICH, KEITH S. MURRAY, BOUJEMA MOUBARAKI, GEORGE LAZAREV, JOHN D. CASHION, and HEINER HOMBORG. "μ-Carbido Diporphyrinates and Diphthalocyaninates of Iron and Ruthenium." Journal of Porphyrins and Phthalocyanines 01, no. 02 (April 1997): 141–57. http://dx.doi.org/10.1002/(sici)1099-1409(199704)1:2<141::aid-jpp18>3.0.co;2-m.

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μ-Carbido diporphyrinates and diphthalocyaninates of general formula [{ Mp 2−}2(μ- C )] ( p 2− = tpp ( M = Fe ), oep ( Fe ), pc ( Fe , Ru ); H 2 tpp : 21H,23H-5,10,15,20-tetraphenylporphine; H 2 oep : 21H,23H-2,3,4,8,12,13,17,18-octaethylporphine; H 2 pc : 29H,31H-phthalocyanine) of formally Fe IV and Ru IV are prepared by a new and improved ‘one-pot’ synthesis. The corresponding chloro complexes of the tervalent metal ions react successively with potassium hydroxide in boiling 2-propanol and then with trichloromethane. Potassium hydroxide is proven to be a very versatile and powerful reductant in tetrapyrrolic chemistry. As evidenced from electron spin resonance and UV vis spectral measurements, the precursor is reduced primarily to an ate-complex of type [ M I p 2−]− of a formally monovalent metal ion. This active species is assumed to react with trichloromethane via a dichlorocarbene complex of type [ M II( CCl 2) p 2−] to yield the actual -carbido complex. [{ Feoep 2−}2(μ- C )] is crystallographically characterized. It is monoclinic, space group C12/c1 (15), with a = 18.279(3) Å, b = 15.005(2) Å, c = 23.392(7) Å, β = 107.12(2)°, Z = 4, R1 = 0.0773. The iron atom is displaced by 0.192(3) Å out of the centre ( Ct ) of the ( N p )4 plane toward the (μ- C ) atom. Average d ( Fe - N p ) is 1.986(5) Å; d ( Fe -(μ- C )) is 1.6638(9) Å. The Fe - C - Fe skeleton is linear (179.5(3)°). The two slightly waving porphyrinato cores are in a staggered conformation, the ( N p - Fe - Fe ″- N p ″) torsion angle being 21.0(3)°. Solutions of each μ-carbido complex in pyridine/dichloromethane show four distinct quasi-reversible redox processes in their differential-pulse voltammograms and these are assigned to the successive one-electron reduction and oxidation of the macrocyclic ligands. 13 C CP MAS NMR spectra indicate effective four-fold symmetry within the series of the μ-carbido complexes with isotropic shifts occurring at similar fields to those of the corresponding macrocyclic complex of a closed-shell metal ion. Resonances of the bridging carbon atom are not detected. A characteristic increase of line broadening within the series tpp 2− > oep 2− > pc 2− may be due to Fermi contact interactions with the strongly coupled low-spin M IV centres. The magnetic susceptibility studies show that the complexes all display non-zero μ values at 295 K increasing from pc 2− to tpp 2−. Mössbauer spectra confirm the low-spin Fe IV oxidation state for the iron centres. Isomer shift, δ, and quadrupole splitting, ΔE Q , for [{ Fepc 2−}2(μ- C )] and [{ Fetpp 2−}2(μ- C )] are identical to those previously reported. Data for [{ Feoep 2−}2(μ- C )] are essentially the same as for the pc and tpp complex. Thus the order of δ is tpp ≈ oep > pc whilst that of Δ E Q is pc >> oep > tpp . Small impurity lines are observed which help explain the magnetic data. UV vis/NIR spectra of the μ-carbido complexes show the characteristic π-π* transitions. These are shifted with respect to the corresponding mononuclear complexes to higher energy because of excitonic interactions. Vibrational spectra are discussed in detail ν as ( M - C - M ) (in cm−1) is at 937 ( M = Fe ; tpp ) < 976 ( Fe / oep ) < 997 ( Fe / pc ) < 1050 ( Ru / pc ), ν s ( M - C - M ) (in cm−1 at 433 ( Fe / tpp ) < 460 ( Fe / oep ) < 477 ( Fe / pc ). Hence, valence force constants increase significantly in the order tpp < oep < pc . ν s ( Fe - C - Fe ) of [{ Fepc 2−}2(μ- C )] is selectively resonance Raman enhanced. As evidenced from the excitation profile a C → Fe charge transfer, not detected in the vis spectrum, is assumed to be present at 22 000 > ν > 25 000 cm −1.

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11

Bădoiu, Andrei, Yasmin Brinkmann, Florian Viton, and E. Peter Kündig. "Asymmetric Lewis acid-catalyzed 1,3-dipolar cycloadditions." Pure and Applied Chemistry 80, no. 5 (January 1, 2008): 1013–18. http://dx.doi.org/10.1351/pac200880051013.

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Highly tuned, one-point binding chiral iron and ruthenium complexes selectively coordinate and activate α,β-unsaturated aldehydes and ketones toward asymmetric catalytic Diels-Alder cycloaddition reactions. Here we focus on the application of these transition-metal Lewis acids to asymmetric catalytic 1,3-dipolar cycloaddition reaction between enals and cyclic and acyclic nitrones as well as aryl nitrile oxides to give isoxazolidines and isoxazolines, respectively.

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12

Zobi, Fabio, and Dennis V. Stynes. "Hetero trinuclear oxo-bridged complexes of ruthenium porphyrin and iron phthalocyanine." Canadian Journal of Chemistry 79, no. 5-6 (May 1, 2001): 795–801. http://dx.doi.org/10.1139/v00-180.

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New diamagnetic hetero bi- and trinuclear oxo-bridged metal complexes of formula (L)(Pc)Fe-O-Ru(TPP')(O) and (L)(Pc)Fe-O-Ru(TPP')-O-Fe(Pc)(L) have been prepared from Ru(TPP')(O)2 and Fe(Pc)(L)2 (TPP' = tetrakis(4-methoxyphenyl)porphyrinate, Pc = phthalocyanate ion, L = monodentate ligand). The trinuclear complex binds a variety of ligands (4,4'-bipy, 4-MePy, P(OEt)3, pip, NH3, 1-MeIm, P(Me)2Ph) trans to the oxo-bridge. 1H NMR spectra are characterized by large ring current shifts (rcs) due to the TPP' and Pc ions. The complexes show an unusually weak Pc Q band in their visible spectra at 700 nm and two CT bands in the near-IR region from 1000 to 1500 nm, which are sensitive to the trans ligand. The trinuclear complex can be reversibly oxidized to the +1 and +2 ions, formally Fe(IV)-O-Ru(IV)-O-Fe(III) and Fe(IV)-O-Ru(IV)-O-Fe(IV) at 0.4 and 0.76 V. The +1 ion is chemically obtained by reaction of the neutral species with (Cp)2Fe+ for L = 4-MePy and this reaction is reversed upon addition of L' = P(Me)2Ph. Reductive cleavage by hydroquinone, phosphines and phosphites are the slowest of all RuTPP[O(FeN4)]2 systems studied to date (t1/2 = 8 h at 40°C).Key words: ruthenium, iron, porphyrin, phthalocyanine, oxo.

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13

Hurrell, Helen C., and HÉCtor D. Abruńa. "Conductivity Studies of Metal Coordination Polymers of Cobalt, Iron, Ruthenium, and Osmium Vinylbipyridine Complexes." Molecular Crystals and Liquid Crystals Incorporating Nonlinear Optics 160, no. 1 (January 1988): 377–88. http://dx.doi.org/10.1080/15421408808083033.

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14

Hurrell, Helen C., and Hector D. Abruna. "Redox conduction in electropolymerized films of transition-metal complexes of osmium, ruthenium, iron, and cobalt." Inorganic Chemistry 29, no. 4 (February 1990): 736–41. http://dx.doi.org/10.1021/ic00329a033.

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15

Fokina, Z. A. "35Cl and 79Br NQR Spectra and the Secondary Bonding of Chalcogen Halide Complexes." Zeitschrift für Naturforschung A 55, no. 1-2 (February 1, 2000): 160–66. http://dx.doi.org/10.1515/zna-2000-1-228.

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The 35Cl and 79Br NQR spectra of chalcogen halide complexes of aluminium, gallium, titanium, zirconium, hafnium, niobium, tantalum, molybdenum, tungsten, rhenium, iron, ruthenium, osmium, iridium, rhodium, platinum, palladium and gold are discussed. Three structure types of these complexes have been distinguished by X-ray structure analysis: type I with AX2 ligand and [MXn„Am] coordination polyhedron; type II with AX3 ligand and [MXn+m] coordination polyhedron; type III, dimeric complexes with M-X-M bridge (where X = Cl, Br and A = S, Se, Te). The formation of secondary M-X-A or M-X-M bonds is characteristic of most structures. The spectra were interpreted by a Townes. Dailey approximation with allowance for the electronic configuration of the metal, mutual influence of ligands and structure features of complexes. Systematic investigation of a big series of chalcogen halide complexes-analogues allowed the following changes in 35CI and 79Br NQR frequencies on secondary bonding to be established for intraligand halogen atoms: A decrease in frequency for type I complexes and an increase in frequency for type II complexes; for halogen atoms in the coordination polyhedron: a decrease in frequency for p metals and transition metals with d>6, and an increase in frequency for metals with d< 6.

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16

Schenk, Wolfdieter A., Ute Karl, and Michael R. Horn. "Kationische Schwefeldioxid-Komplexe des Eisens und Rutheniums vom Halbsandwich-Typ [1] / Cationic Halfsandwich-Type Sulfur Dioxide Complexes of Iron and Ruthenium [1]." Zeitschrift für Naturforschung B 44, no. 12 (December 1, 1989): 1513–18. http://dx.doi.org/10.1515/znb-1989-1208.

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Cationic halfsandwich-type complexes of sulfur dioxide, [C5R5M(PR3)2(SO2)]+ (R = H, Me, M = Fe, Ru, (PR3)2 = mono- or bidentate phosphorus ligands) and [C5Me5Fe(CO)(PR3)(SO2)]+, are obtained by ligand exchange from labile cationic (M = Fe) or neutral (M = Ru) precursors. The new compounds are characterized by IR, 1H131H, 13C and 31P NMR spectroscopy. Their stability increases with increasing electron density at the metal.

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17

Moores, Audrey, Nicolas Mézailles, Louis Ricard, François Mathey, and Pascal Le Floch. "Neutral and dianionic iron and ruthenium 1,4-diphosphabutadiene complexes." Chem. Commun., no. 15 (2003): 1914–15. http://dx.doi.org/10.1039/b304243j.

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18

Smith, Mark E., Richard L. Cordiner, David Albesa-Jové, Dmitri S. Yufit, František Hartl, Judith AK Howard, and Paul J. Low. "The synthesis, structure, and electrochemical properties of Fe(C≡CC≡N)(dppe)Cp and related compounds." Canadian Journal of Chemistry 84, no. 2 (February 1, 2006): 154–63. http://dx.doi.org/10.1139/v05-238.

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The cyanoacetylide complex Fe(C≡CC≡N)(dppe)Cp (3) is readily obtained from sequential reaction of Fe(C≡CSiMe3)(dppe)Cp with methyllithium and phenyl cyanate. Complex 3 is a good metalloligand, and coordination to the metal fragments [RhCl(CO)2], [Ru(PPh3)2Cp]+, and [Ru(dppe)Cp*]+ affords the corresponding cyanoaceylide-bridged heterobimetallic complexes. In the case of the 36-electron complexes [Cp(dppe)Fe-C≡CC≡N-MLn]n+, spectroscopic and structural data are consistent with a degree of charge transfer from the iron centre to the rhodium or ruthenium centre via the C3N bridge, giving rise to a polarized ground state. Electrochemical and spectroelectrochemical methods reveal significant interactions between the metal centres in the oxidized (35 electron) derivatives, [Cp(dppe)Fe-C≡CC≡N-MLn](n+1)+. Key words: cyanide, cyanoacetylide, crystal structure.

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19

Craig, Donald C., Marcia L. Scudder, Wendy-Anne McHale, and Harold A. Goodwin. "Structural Studies of Complexes of Tridentate Terimine Systems. Crystal Structure of Bis(2,2′:6′,2′′-terpyridine)ruthenium(II) Perchlorate Hydrate, Bis(2,2′:6′,2′′-terpyridine)- osmium(II) Perchlorate Hemihydrate and Bis((1,10-phenanthrolin-2-yl)(pyridin-2-yl)amine)iron(II) Tetrafluoroborate Dihydrate." Australian Journal of Chemistry 51, no. 12 (1998): 1131. http://dx.doi.org/10.1071/c98118.

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The crystal structures of bis(2,2′:6′,2″-terpyridine)ruthenium(II) perchlorate hydrate, bis(2,2′:6′,2″- terpyridine)osmium(II) perchlorate hemihydrate and bis((1,10-phenanthrolin-2-yl)(pyridin-2-yl)- amine)iron(II) tetrafluoroborate dihydrate are described. In the terpyridine complexes the ruthenium-nitrogen distances and the corresponding osmium-nitrogen distances are not significantly different. In both complexes the ligand geometry and the metal ion environment show the distortions usual for bis(terpyridine) systems. Distortions are less marked in the bis((1,10-phenanthrolin-2-yl)(pyridin-2-yl)amine)iron(II) cation in which each tridentate unit forms one five-membered and one six-membered chelate ring. [Ru(trpy)2] [ClO4]2.(H2O)1.1: tetragonal, space group I 41/a, a, b 12·527(2), c 40·202(11) Å, Z 8. [Os(trpy)2] [ClO4]2.(H2O)0·5: monoclinic, space group P 21/n, a 8·842(3), b 8·861(1), c 39·22(2) Å, β93·89(2)°, Z 4. [Fe(phpyam)2] [BF4]2.(H2O)2: triclinic, space group P -1, a 12·43(1), b 12·45(1), c 13·35(1) Å, α 62·70(10), β 78·55(8), γ 72·46(9)°, Z 2.

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20

Unsleber, Jan P., Johannes Neugebauer, and Robert H. Morris. "DFT methods applied to answer the question: how accurate is the ligand acidity constant method for estimating the pKa of transition metal hydride complexes MHXL4 when X is varied?" Dalton Transactions 47, no. 8 (2018): 2739–47. http://dx.doi.org/10.1039/c7dt03473c.

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Additive ligand acidity constants A_L of anionic ligands are calculated for neutral hydrides of iron(ii), ruthenium(ii) and osmium(ii) with phosphine and carbonyl co-ligands; constant A_L in green, more variable A_L in red.

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21

Schenk, Wolfdieter A., Ute Karl, Michael R. Horn, and Stefan Müssig. "Schwefelmonoxid als Ligand in kationischen Halbsandwich-Komplexen des Eisens und Rutheniums [1] / Sulfur Monoxide as Ligand in Cationic Halfsandwich Type Complexes of Iron and Ruthenium [1]." Zeitschrift für Naturforschung B 45, no. 2 (February 1, 1990): 239–44. http://dx.doi.org/10.1515/znb-1990-0218.

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Cationic halfsandwich type iron sulfur monoxide complexes [cpFe(L—L)(SO)]+ (L— L = dppe, cdpe) and [cp*Fe(PMe3)2(SO)]+ are obtained by transition metal-induced SO transfer from thiirane-1-oxide. With the sterically unhindered fragment [cpFe(dmpe)]+ a binuclear SO-bridged dication is formed instead. Reaction of [cpRu(PR3)2Cl] (R = Me, Ph) and [cpRu(dppe)Cl] with thiirane-1-oxide gives mixtures of the known cations [cpRuL2(SO2)]+ and [(cpRuL2)2(μ-S2)]2+, probably via the expected mononuclear SO complexes which disproportionate at low temperature. The more electron-rich cation [cp*Ru(PMe3)2(SO)]+, however, is stable. Reactions with pyridine, PMe3, and 3-chloroperbenzoic acid demonstrate that the coordinated SO can be attacked by nucleophiles as well as electrophiles.

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22

Sheu, Jeng-Horng, and Ming-Der Su. "A computational study of cycloaddition reactions of d8 metal tetroxide (Iron, Ruthenium, Osmium) complexes with C60." Dalton Transactions 40, no. 16 (2011): 4122. http://dx.doi.org/10.1039/c0dt01445a.

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23

Bautista, Maria Teresa, Kelly Anne Earl, Patricia Anne Maltby, Robert Harold Morris, and Caroline Theresia Schweitzer. "New dihydrogen complexes: the synthesis and spectroscopic properties of iron(II), ruthenium(II), and osmium(II) complexes containing the meso-tetraphos-1 ligand." Canadian Journal of Chemistry 72, no. 3 (March 1, 1994): 547–60. http://dx.doi.org/10.1139/v94-078.

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The synthesis and properties of dihydrogen complexes trans-[MH(H2)L]+, M = Fe, Ru, Os, which contain the ligand meso-tetraphos-1, S,R-Ph2PCH2CH2P(Ph)CH2CH2P(Ph)CH2CH2PPh2 (L) are described. There are interesting possibilities of isomerism in such trans complexes because the axial binding sites at the metal are different, one being surrounded by four phenyl groups and the other by two phenyl groups. The osmium complex is prepared in an unusual reaction of cis-β-Os(Cl)2L with H2 (1 atm) and NaBPh4 (1 mol) in THF or by the reaction of trans-OsH(Cl)L with NaBPh4 and H2. The iron and ruthenium complexes were made by a reaction of HBF4 with complexes trans-M(H)2L that have inequivalent trans hydrides. The ruthenium complex was also prepared starting from isomers of trans-RuH(Cl)L. The H—H distance in the rapidly spinning dihydrogen ligand has been calculated from T1(min) data to be 0.88, 0.89, and 0.99 Å for the complexes of Fe, Ru, Os, respectively. The presence of the H—D bond in the isotopomers trans-[MH(HD)L]+ and trans-[MD(HD)L]+ is also confirmed by the observation of 1JHD coupling constants of 32, 33.5, and 26.4 Hz for Fe, Ru, and Os, respectively. There is no rapid intramolecular H atom exchange in these complexes in contrast to those with di-tert-phosphine ligands like [MH(H2)(dppe)2]+ or to the trihydride Re(H)3L. Described also are the properties of the precursor complexes including cis-β- and trans-Ru(Cl)2L and derivatives of the dihydrogen complexes trans-[MH(L′)L]+, L′ = CH3CN (on Ru and Os), PMe2Ph (on Ru), and CO (on Os). Trends in the NMR properties of isostructural complexes are reported.

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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 (March 28, 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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Alberto, Marta Erminia, Stefania Di Tommaso, Chiara Ricca, Ilaria Ciofini, and Carlo Adamo. "Dioxygenation of metal(II)-cysteinato complexes in CDO biomimetic models: Can ruthenium and osmium reach iron performances?" International Journal of Quantum Chemistry 118, no. 9 (November 14, 2017): e25525. http://dx.doi.org/10.1002/qua.25525.

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26

Pfister, Bernhard, Ruedi Stauber, and Albrecht Salzer. "Optically active transition-metal complexes VII Iron and ruthenium complexes with the optically active cyclopentadienyl ligand PCp: syntheses and ligand exchange reactions." Journal of Organometallic Chemistry 533, no. 1-2 (April 1997): 131–41. http://dx.doi.org/10.1016/s0022-328x(96)06849-0.

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27

WEBER, L., and U. SONNENBERG. "ChemInform Abstract: Transition Metal-Substituted Diphosphenes. Part 23. Synthesis and Reactivity of Dihalophosphido Complexes of Iron and Ruthenium." ChemInform 22, no. 25 (August 23, 2010): no. http://dx.doi.org/10.1002/chin.199125220.

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28

Macartney, Donal H. "The oxidation of hydrogen peroxide by tris(polypyridine) complexes of osmium(III), iron(III), ruthenium(III), and nickel(III) in aqueous media." Canadian Journal of Chemistry 64, no. 9 (September 1, 1986): 1936–42. http://dx.doi.org/10.1139/v86-319.

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The stoichiometry and kinetics of the oxidation of hydrogen peroxide by tris(2,2′-bipyridine) and tris(4,4′-dimethyl-2,2′-bipyridine) complexes of osmium(III), iron(III), ruthenium(III), and nickel (III) were studied in acidic and neutral aqueous media at 25 °C and I = 0.50 M (LiCF3SO3). The reaction 2M(bpy)33+ + H2O2 → 2M(bpy)32+ + O2 + 2H+ is observed with quantitative yields of dioxygen gas. The observed rate constants displayed an inverse acid dependence over the pH range 6.0–8.5; kobsd = k1 + k2K1/[H+], attributed to the oxidations of H2O2(k1) and HO2− (k2). An application of the Marcus theory relationship to the cross-reaction data gave a self-exchange rate constant of 10−2–10−1 M−1 s−1 for the HO2−/HO2 couple. The electron exchange rate constant is evaluated in terms of the inner-sphere and solvent reorganizational barriers and is compared to values reported for other small molecule couples. Rate and activation parameters for the reduction of the nickel(III) complexes by the hydroxide ion have been determined and are compared with the corresponding values for other metal tris(poly pyridine) complexes.

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29

Fiedler, Jan. "On the Electrochemical, Spectral and Photochemical Properties of Cyano-Nitrosyl Complexes. A Comparison between Iron and Ruthenium Analogues." Collection of Czechoslovak Chemical Communications 58, no. 3 (1993): 461–73. http://dx.doi.org/10.1135/cccc19930461.

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First order rate constant of cyanide splitting from one-electron product of the nitropruside ion reduction was determined using a.c. polarography (k = 350 s-1 in CH3CN). [Ru(CN)5(NO)]2- ion is reduced reversibly (E1/2 = -1.04 V, k0 = 4.86 . 10-3 m s -1 in CH3CN; E1/2 = -0.39 V in H2O) with one electron. IR and EPR study indicates dimerization of the reduction product in solution but no cyanide splitting from electrogenerated [Ru(CN)5(NO)]3- was detected. Further reduction of [Ru(CN)5(NO)]3-, with consumption of protons occurs in aqueous media. Efficient photochemical reactions of [Fe(CN)4(NO)]2- with O2, KMNO4 and pyridine take place when the complex is excited at the metal-to-nitrosyl charge transfer band.

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30

Coffy, Tim J., George Medford, Jeffrey Plotkin, Gary J. Long, John C. Huffman, and Sheldon G. Shore. "Metalladiboranes of the iron subgroup: K[M(CO)4(.eta.2-B2H5)] (m- iron, ruthenium, osmium) and M'(.eta.5-C5H5) (CO)2(.eta.2-B2H5) (M' = iron, ruthenium). Analogs of metal-olefin complexes." Organometallics 8, no. 10 (October 1989): 2404–9. http://dx.doi.org/10.1021/om00112a023.

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31

Davis, James H., Ekk Sinn, and Russell N. Grimes. "Organotransition-metal metallacarboranes. 12. Arene-metal-carborane triple-decker sandwiches. Designed synthesis of homo- and heterobimetallic complexes of cobalt, iron, ruthenium, and osmium." Journal of the American Chemical Society 111, no. 13 (June 1989): 4776–84. http://dx.doi.org/10.1021/ja00195a034.

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32

Turan, Nevin, and Kenan Buldurun. "Synthesis, characterization and antioxidant activity of Schiff base and its metal complexes with Fe(II), Mn(II), Zn(II), and Ru(II) ions: Catalytic activity of ruthenium(II) complex." European Journal of Chemistry 9, no. 1 (March 31, 2018): 22–29. http://dx.doi.org/10.5155/eurjchem.9.1.22-29.1671.

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The synthesis, spectral, catalytic and antioxidant properties of ethyl-2-(2-hydroxy-3-methoxybenzylideneamino)-6-methyl-4,5,6-tetrahydrobenzo[b]thiophene-3-carboxylate (L) substituted iron(II), manganese(II), zinc(II), and ruthenium(II)-arene chlorides are described for the first time. The ligand and its metal complexes were characterized by elemental analysis, molar conductance, magnetic susceptibility measurements, and spectral (1H NMR, 13C NMR, FT-IR, UV-Vis and Mass) techniques. The FT-IR spectra showed that the ligand can act as bidentate or tridentate. Magnetic moments and electronic spectral studies revealed an octahedral geometry for all the complexes obtained. The thermal behavior of the complexes showed that the water molecules were separated in the first step followed immediately by decomposition of the anions and ligand molecules in the subsequent steps. Ru(II) complex was used as catalysts for the transfer hydrogenation of ketones. At the same time, the effect of various bases such as NaOH, KOH, KOBut and NaOAc as organic base were investigated in the transfer hydrogenation of ketones by 2-propanol as the hydrogen source. The complexes and ligand were tested in vitro for their antioxidant activity. The experimental results showed that Ru(II) complex had more potent antioxidant activities than Zn(II), Fe(II), Mn(II) complexes and parent ligand.

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33

Low, Kian Sing, Jacqueline M. Cole, Xiaolan Zhou, and Nataliya Yufa. "Rationalizing the molecular origins of Ru- and Fe-based dyes for dye-sensitized solar cells." Acta Crystallographica Section B Structural Science 68, no. 2 (March 20, 2012): 137–49. http://dx.doi.org/10.1107/s0108768112009263.

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As part of an effort to design more efficient dyes for dye-sensitized solar cells (DSCs), structure–property relationships are established in the world's best-performing chemical series of dyes: 2,2′-bipyridyl-4,4′-carboxylatoruthenium(II) complexes. Statistical analysis, based on crystallographic data from the Cambridge Structural Database, is used to determine common structural features and the effects of structural change to its salient molecular constituents. Also included is the report of two new crystal structures for tris(2,2′-bipyridyl)dichlororuthenium(II)hexahydrate and tris(2,2′-bipyridyl)iron(II)dithiocyanate; these add to this statistical enquiry. Results show that the metal (M) core exhibits a distorted octahedral environment with M—N π-backbonding effects affording the propensity of the metal ion towards oxidation. The same characteristics are observed in iron-based analogues. The role of carboxylic groups in this series of dyes is assessed by comparing complexes which contain or are devoid of COOH groups. Space-group variation and large molecular conformational differences occur when COOH groups are present, while such structural features are very similar in their absence. The nature of the anion is also shown to influence the structure of COOH-containing complexes. These structural findings are corroborated by solution-based UV–vis absorption spectroscopy and DSC device performance tests. The presence of COOH groups in this series of compounds is shown to be mandatory for dye-uptake in TiO2 in the DSC fabrication process. Throughout this study, results are compared with those of the world's most famous DSC dye, N3 (N719 in its fully protonated form): cis-bis(isothiocyanato)bis(2,2′-bipyridyl-4,4′-dicarboxylato)ruthenium(II). Overall, the molecular origins of charge-transfer in these complexes are ascertained. The findings have important implications to the materials discovery of more efficient dyes for DSC technology.

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34

Davies, David L., John Fawcett, Julie Neild, and David R. Russell. "Metal complexes of functionalized phosphines—III. Synthesis and characterization of 2-diphenylphosphinoethylamine complexes with iron and ruthenium. Crystal structure of [(η5-C5H5)RNHBut)]Cl." Polyhedron 13, no. 20 (October 1994): 2923–28. http://dx.doi.org/10.1016/s0277-5387(00)86626-7.

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35

Davis, James H., Martin D. Attwood, and Russell N. Grimes. "Organotransition-metal metallacarboranes. 15. Regiospecific B-alkylation of (arene)M(Et2C2B3H5) (M = iron, ruthenium) and (C5Me5)Co(Et2C2B3H5) sandwich complexes." Organometallics 9, no. 4 (April 1990): 1171–76. http://dx.doi.org/10.1021/om00118a043.

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36

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 (January 1991): 221–25. http://dx.doi.org/10.1016/1359-0197(91)90132-l.

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37

Weber, Lothar, Klaus Reizig, and Georg Meine. "Übergangsmetall-substituierte Acylphosphane und Phosphaalkene, VI [1] Phosphaalkenyl-Eisen- und -Rutheniumkomplexe mit Metall-Kohlenstoffkoordination / Transition Metal Substituted Acylphosphines and Phosphaalkenes, VI [1] Phosphaalkenyl Iron and Ruthenium Complexes with Metal-Carbon Coordination." Zeitschrift für Naturforschung B 40, no. 12 (December 1, 1985): 1698–702. http://dx.doi.org/10.1515/znb-1985-1216.

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Abstract Treatment of the cationic complexes [(η5-C5Me5)M(CO)3]⊕BF4⊖ (M = Fe, Ru) (1a , b) with the bulky lithium silyl phosphide LiP(Ar')(SiMe3) (Ar' = 2,4,6-tri-fert-butylphenyl) (2) leads to the phosphaalkenyl complexes (η5-C5Me5)(CO)2M - C(OSiMe3) = P ~ Ar' (4a, b). The presence of C = P double bonds in 4a, b was ascertained by 13C- and 31P NMR spectra. The geometry at the C = P bond was also deduced from the analysis o f the NMR spectra (1H , 13C, 31P)

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38

Diez-Cabanes, Valentin, Giacomo Prampolini, Antonio Francés-Monerris, Antonio Monari, and Mariachiara Pastore. "Iron’s Wake: The Performance of Quantum Mechanical-Derived Versus General-Purpose Force Fields Tested on a Luminescent Iron Complex." Molecules 25, no. 13 (July 6, 2020): 3084. http://dx.doi.org/10.3390/molecules25133084.

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Recently synthetized iron complexes have achieved long-lived excited states and stabilities which are comparable, or even superior, to their ruthenium analogues, thus representing an eco-friendly and cheaper alternative to those materials based on rare metals. Most of computational tools which could help unravel the origin of this large efficiency rely on ab-initio methods which are not able, however, to capture the nanosecond time scale underlying these photophysical processes and the influence of their realistic environment. Therefore, it exists an urgent need of developing new low-cost, but still accurate enough, computational methodologies capable to deal with the steady-state and transient spectroscopy of transition metal complexes in solution. Following this idea, here we focus on the comparison between general-purpose transferable force-fields (FFs), directly available from existing databases, and specific quantum mechanical derived FFs (QMD-FFs), obtained in this work through the Joyce procedure. We have chosen a recently reported FeIII complex with nanosecond excited-state lifetime as a representative case. Our molecular dynamics (MD) simulations demonstrated that the QMD-FF nicely reproduces the structure and the dynamics of the complex and its chemical environment within the same precision as higher cost QM methods, whereas general-purpose FFs failed in this purpose. Although in this particular case the chemical environment plays a minor role on the photo physics of this system, these results highlight the potential of QMD-FFs to rationalize photophysical phenomena provided an accurate QM method to derive its parameters is chosen.

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39

Young, George H., Marline V. Raphael, Andrew Wojcicki, Mario Calligaris, Giorgio Nardin, and Nevina Bresciani-Pahor. "Reactions of molybdenum- and tungsten-propargyl compounds with iron and ruthenium carbonyls. Synthesis and reactivity of heteronuclear metal-.mu.-allenyl complexes." Organometallics 10, no. 6 (June 1991): 1934–45. http://dx.doi.org/10.1021/om00052a046.

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40

Voloshin, Yan Z., Vyacheslav M. Buznik, and Alexey G. Dedov. "New types of the hybrid functional materials based on cage metal complexes for (electro) catalytic hydrogen production." Pure and Applied Chemistry 92, no. 7 (July 28, 2020): 1159–74. http://dx.doi.org/10.1515/pac-2019-1105.

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AbstractSuccessful using of cage metal complexes (clathrochelates) and the functional hybrid materials based on them as promising electro- and (pre)catalysts for hydrogen and syngas production is highlighted in this microreview. The designed polyaromatic-terminated iron, cobalt and ruthenium clathrochelates, adsorbed on carbon materials, were found to be the efficient electrocatalysts of the hydrogen evolution reaction (HER), including those in polymer electrolyte membrane (PEM) water electrolysers. The clathrochelate-electrocatalayzed performances of HER 2H+/H2 in these semi-industrial electrolysers are encouraging being similar to those for the best known to date molecular catalysts and for the promising non-platinum solid-state HER electrocatalysts as well. Electrocatalytic activity of the above clathrochelates was found to be affected by the number of the terminal polyaromatic group(s) per a clathrochelate molecule and the lowest Tafel slopes were obtained with hexaphenanthrene macrobicyclic complexes. The use of suitable carbon materials of a high surface area, as the substrates for their efficient immobilization, allowed to substantially increase an electrocatalytic activity of the corresponding clathrochelate-containing carbon paper-based cathodes. In the case of the reaction of dry reforming of methane (DRM) into syngas of a stoichiometry CO/H2 1:1, the designed metal(II) clathrochelates with terminal polar groups are only the precursors (precatalysts) of single atom catalysts, where each of their catalytically active single sites is included in a matrix of its former encapsulating ligand. Choice of their designed ligands allowed an efficient immobilization of the corresponding cage metal complexes on the surface of a given highly porous ceramic material as a substrate and caused increasing of a surface concentration of the catalytically active centers (and, therefore, that of the catalytic activity of hybrid materials modified with these clathrochelates). Thus designed cage metal complexes and hybrid materials based on them operate under the principals of “green chemistry” and can be considered as efficient alternatives to some classical inorganic and molecular (pre)catalysts of these industrial processes.

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41

Li, Yan, Chi-Wing Tsang, Eve Man Hin Chan, Eugene Yin Cheung Wong, Danny Chi Kuen Ho, Xiao-Ying Lu, and Changhai Liang. "Sustainable Option for Hydrogen Production: Mechanistic Study of the Interaction between Cobalt Pincer Complexes and Ammonia Borane." Catalysts 10, no. 7 (June 28, 2020): 723. http://dx.doi.org/10.3390/catal10070723.

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The mechanism of the solvolysis/hydrolysis of ammonia borane by iridium (Ir), cobalt (Co), iron (Fe) and ruthenium (Ru) complexes with various PNP ligands has been revisited using density functional theory (DFT). The approach of ammonia borane (NH3BH3) to the metal center has been tested on three different possible mechanisms, namely, the stepwise, concerted and proton transfer mechanism. It was found that the theoretical analyses correlate with the experimental results very well, with the activities of the iridium complexes with different PNP ligands following the order: (tBu)2P > (iPr)2P > (Ph)2P through the concerted mechanism. The reaction barriers of the rate-determining steps for the dehydrogenation of ammonia borane catalyzed by the active species [(tBu)2PNP-IrH] (Complex I-8), are found to be 19.3 kcal/mol (stepwise), 15.2 kcal/mol (concerted) and 26.8 kcal/mol (proton transfer), respectively. Thus, the concerted mechanism is the more kinetically favorable pathway. It is interesting to find that stable (tBu)2PNP Co-H2O and (tBu)2PNP Co-NH3 chelation products exist, which could stabilize the active I-8 species during the hydrolysis reaction cycle. The use of more sterically hindered and electron-donating PNP ligands such as (adamantyl)2P- provides similar activity as the t-butyl analogue. This research provides insights into the design of efficient cobalt catalysts instead of using precious and noble metal, which could benefit the development of a more sustainable hydrogen economy.

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42

Rivera-Utrilla, José, María Victoria López-Ramón, Manuel Sánchez-Polo, Miguel Ángel Álvarez, and Inmaculada Velo-Gala. "Characteristics and Behavior of Different Catalysts Used for Water Decontamination in Photooxidation and Ozonation Processes." Catalysts 10, no. 12 (December 19, 2020): 1485. http://dx.doi.org/10.3390/catal10121485.

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The objective of this study was to summarize the results obtained in a wide research project carried out for more than 15 years on the catalytic activity of different catalysts (activated carbon, metal–carbon xerogels/aerogels, iron-doped silica xerogels, ruthenium metal complexes, reduced graphene oxide-metal oxide composites, and zeolites) in the photooxidation (by using UV or solar radiation) and ozonation of water pollutants, including herbicides, naphthalenesulfonic acids, sodium para-chlorobenzoate, nitroimidazoles, tetracyclines, parabens, sulfamethazine, sodium diatrizoate, cytarabine, and surfactants. All catalysts were synthesized and then texturally, chemically, and electronically characterized using numerous experimental techniques, including N2 and CO2 adsorption, mercury porosimetry, thermogravimetric analysis, X-ray diffraction, Fourier-transform infrared spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, diffuse reflectance UV–vis spectroscopy, photoluminescence analysis, and transmission electron microscopy. The behavior of these materials as photocatalysts and ozonation catalysts was related to their characteristics, and the catalytic mechanisms in these advanced oxidation processes were explored. Investigations were conducted into the effects on pollutant degradation, total organic carbon reduction, and water toxicity of operational variables and the presence of different chemical species in ultrapure, surface, ground, and wastewaters. Finally, a review is provided of the most recent and relevant published studies on photocatalysis and catalyzed ozonation in water treatments using similar catalysts to those examined in our project.

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43

Willis, Richard R., Chris E. Shuchart, Andrew Wojcicki, Arnold L. Rheingold, and Brian S. Haggerty. "Heterobinuclear and Heterotrinuclear Metal μ-Allenyl Complexes Containing Platinum and One or Both of Iron and Ruthenium. Synthesis of Higher Nuclearity Metal Complexes from Mononuclear Metal η1-Propargyls and η1-Allenyls and from Binuclear Metal μ-η1:η2α,β-Allenyls." Organometallics 19, no. 16 (August 2000): 3179–91. http://dx.doi.org/10.1021/om000205g.

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44

Pandey, Krishna K., and Simon Aldridge. "Nature of M−Ga Bonds in Cationic Metal-Gallylene Complexes of Iron, Ruthenium, and Osmium, [(η5-C5H5)(L)2M(GaX)]+: A Theoretical Study." Inorganic Chemistry 50, no. 5 (March 7, 2011): 1798–807. http://dx.doi.org/10.1021/ic102217z.

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45

Weber, Lothar, and Georg Meine. "Übergangsmetall-substituierte Diphosphene, VI [1]Zur Reaktivität von Diphosphenylkomplexen des Eisens und Rutheniums gegenüber Tetracarbonylnickel / Transition Metal Substituted Diphosphenes, VI [1] On the Reactivity of Diphosphenyl Complexes of Iron and Ruthenium towards Tetracarbonyl Nickel." Zeitschrift für Naturforschung B 42, no. 6 (June 1, 1987): 774–76. http://dx.doi.org/10.1515/znb-1987-0622.

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Abstract The diphosphenyl complexes (?/ 5 -CsMe0(CO 2)M-P = P-Ar (8) (M = Fe, Ru; Ar = 2,4,6-rm-BU,C 6 H 2) react with excess Ni(CO) 4 to yield the adducts (77 5 -C 5 Me 5)(CO) 2 M[Ni(CO) 3 ]P=PAr (9). The products have been characterized by elemental analysis as well as by spectroscopic data (IR. 'H, 13 C, 31 P NMR).

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46

Corraine, M. Shauna, and Jim D. Atwood. "Electron transfer between metal cluster complexes: reaction of the dianions M3(CO)112- with the dodecacarbonyltrimetal clusters M3(CO)12 (M = iron, ruthenium, osmium)." Organometallics 10, no. 8 (August 1991): 2985–86. http://dx.doi.org/10.1021/om00054a084.

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47

Pardue, Daniel B., Jiajun Mei, Thomas R. Cundari, and T. Brent Gunnoe. "Density Functional Theory Study of Oxygen-Atom Insertion into Metal–Methyl Bonds of Iron(II), Ruthenium(II), and Osmium(II) Complexes: Study of Metal-Mediated C–O Bond Formation." Inorganic Chemistry 53, no. 6 (February 26, 2014): 2968–75. http://dx.doi.org/10.1021/ic402759w.

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48

Adams, Richard D., James E. Babin, Pradeep Mathur, K. Natarajan, and Jin Guu Wang. "Cluster synthesis. 25. Synthesis and characterization of new mixed-metal cluster complexes by metal-metal exchange. Reactions of the sulfido cluster complexes M3(CO)9(.mu.3-CO)(.mu.3-S) (M = iron, ruthenium and osmium) with W(CO)5L (L = CO or PMe2Ph)." Inorganic Chemistry 28, no. 8 (April 1989): 1440–45. http://dx.doi.org/10.1021/ic00307a005.

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49

Van Duyne, Richard P., Jeanne P. Haushalter, Maria Janik-Czachor, and Nancy Levinger. "Surface-enhanced resonance Raman spectroscopy of adsorbates on semiconductor electrode surfaces. 2. In situ studies of transition metal (iron and ruthenium) complexes on silver/gallium arsenide and silver/silicon." Journal of Physical Chemistry 89, no. 19 (September 1985): 4055–61. http://dx.doi.org/10.1021/j100265a026.

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50

Olabe, José. "Coordination Chemistry of Nitric Oxide and Biological Signaling." Science Reviews - from the end of the world 2, no. 1 (December 18, 2020): 64–99. http://dx.doi.org/10.52712/sciencereviews.v2i1.33.

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Nitric Oxide (NO) is a key intermediate in the nitrogen redox cycles that operate in soils, water and biological fluids, affording reversible interconversions between nitrates to ammonia and vice-versa. The discovery of its biosynthesis in mammals for signaling purposes generated a research explosion on the ongoing chemistry occurring in specific cellular compartments, centered on NO reactivity toward O2, thiols, amines, and transition metals, as well as derivatives thereof. The present review deals with the coordination chemistry of NO toward selected iron and ruthenium centers. We place specific attention to the three redox states of the nitrosyl group: NO+, NO and NO–/HNO, describing changes in structure and reactivity as coordination takes place. Noteworthy are the results with the most reduced nitroxyl-species that allow establishing the changes in the measurable pKa values for the HNO-bound complexes, also revealing the abrupt decrease in reducing power and trans-releasing abilities of the protonated species over the unprotonated ones, NO–. Comparative results using non-heme and heme proteins and models prove useful for suggesting further improvements in the current research status of complex enzymatic behavior.

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