1
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Medvedev AG, Egorov PA, Mikhaylov AA, Belyaev ES, Kirakosyan GA, Gorbunova YG, Filippov OA, Belkova NV, Shubina ES, Brekhovskikh MN, Kirsanova AA, Babak MV, Lev O, Prikhodchenko PV. Synergism of primary and secondary interactions in a crystalline hydrogen peroxide complex with tin. Nat Commun 2024; 15:5758. [PMID: 38982085 PMCID: PMC11233698 DOI: 10.1038/s41467-024-50164-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Accepted: 07/01/2024] [Indexed: 07/11/2024] Open
Abstract
Despite the significance of H2O2-metal adducts in catalysis, materials science and biotechnology, the nature of the interactions between H2O2 and metal cations remains elusive and debatable. This is primarily due to the extremely weak coordinating ability of H2O2, which poses challenges in characterizing and understanding the specific nature of these interactions. Herein, we present an approach to obtain H2O2-metal complexes that employs neat H2O2 as both solvent and ligand. SnCl4 effectively binds H2O2, forming a SnCl4(H2O2)2 complex, as confirmed by 119Sn and 17O NMR spectroscopy. Crystalline adducts, SnCl4(H2O2)2·H2O2·18-crown-6 and 2[SnCl4(H2O2)(H2O)]·18-crown-6, are isolated and characterized by X-ray diffraction, providing the complete characterization of the hydrogen bonding of H2O2 ligands including geometric parameters and energy values. DFT analysis reveals the synergy between a coordinative bond of H2O2 with metal cation and its hydrogen bonding with a second coordination sphere. This synergism of primary and secondary interactions might be a key to understanding H2O2 reactivity in biological systems.
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Affiliation(s)
- Alexander G Medvedev
- Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Moscow, Russian Federation
| | - Pavel A Egorov
- Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Moscow, Russian Federation
| | - Alexey A Mikhaylov
- Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Moscow, Russian Federation
| | - Evgeny S Belyaev
- Frumkin Institute of Physical Chemistry and Electrochemistry of the Russian Academy of Sciences, Moscow, Russian Federation
| | - Gayane A Kirakosyan
- Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Moscow, Russian Federation
- Frumkin Institute of Physical Chemistry and Electrochemistry of the Russian Academy of Sciences, Moscow, Russian Federation
| | - Yulia G Gorbunova
- Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Moscow, Russian Federation
- Frumkin Institute of Physical Chemistry and Electrochemistry of the Russian Academy of Sciences, Moscow, Russian Federation
| | - Oleg A Filippov
- Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow, Russian Federation
| | - Natalia V Belkova
- Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow, Russian Federation
| | - Elena S Shubina
- Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow, Russian Federation
| | - Maria N Brekhovskikh
- Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Moscow, Russian Federation
| | - Anna A Kirsanova
- Drug Discovery Lab, Department of Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR, China
| | - Maria V Babak
- Drug Discovery Lab, Department of Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR, China.
| | - Ovadia Lev
- Casali Center of Applied Chemistry, Hebrew University of Jerusalem, Jerusalem, Israel.
| | - Petr V Prikhodchenko
- Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Moscow, Russian Federation.
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2
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Pektas H, Demidov Y, Ahvan A, Abie N, Georgieva VS, Chen S, Farè S, Brachvogel B, Mathur S, Maleki H. MXene-Integrated Silk Fibroin-Based Self-Assembly-Driven 3D-Printed Theragenerative Scaffolds for Remotely Photothermal Anti-Osteosarcoma Ablation and Bone Regeneration. ACS MATERIALS AU 2023; 3:711-726. [PMID: 38089660 PMCID: PMC10636780 DOI: 10.1021/acsmaterialsau.3c00040] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 08/20/2023] [Accepted: 08/29/2023] [Indexed: 12/30/2023]
Abstract
Aiming to address the bone regeneration and cancer therapy functionalities in one single material, in this study, we developed a dual-functional theragenerative three-dimensional (3D) aerogel-based composite scaffold from hybridization of photo-cross-linked silk fibroin (SF) biopolymer with MXene (Ti3C2) two-dimensional (2D) nanosheets. To fabricate the scaffold, we first develop a dual-cross-linked SF-based aerogel scaffold through 3D printing and photo-cross-linking of the self-assembly-driven methacrylate-modified SF (SF-MA) gel with controlled pore size, macroscopic geometry, and mechanical stability. In the next step, to endow a remotely controlled photothermal antiosteosarcoma ablation function to fabricated aerogel scaffold, MXene 2D nanosheets with strong near-infrared (NIR) photon absorption properties were integrated into the 3D-printed scaffolds. While 3D-printed MXene-modified dual-cross-linked SF composite scaffolds can mediate the in vitro growth and proliferation of preosteoblastic cell lines, they also endow a strong photothermal effect upon remote irradiation with NIR laser but also significantly stimulate bone mineral deposition on the scaffold surface. Additionally, besides the local release of the anticancer model drug, the generated heat (45-53 °C) mediated the photothermal ablation of cancer cells. The developed aerogel-based composites and chosen therapeutic techniques are thought to render a significant breakthrough in biomaterials' future clinical applications.
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Affiliation(s)
- Hadice
Kübra Pektas
- Department
of Chemistry, Institute of Inorganic Chemistry, University of Cologne, Cologne 50939, Germany
| | - Yan. Demidov
- Department
of Chemistry, Institute of Inorganic Chemistry, University of Cologne, Cologne 50939, Germany
| | - Aslin Ahvan
- Department
of Chemistry, Institute of Inorganic Chemistry, University of Cologne, Cologne 50939, Germany
| | - Nahal Abie
- Department
of Chemistry, Institute of Inorganic Chemistry, University of Cologne, Cologne 50939, Germany
- Department
of Chemistry, Materials and Chemical Engineering, Politecnico di Milano, Milano 20054, Italy
| | - Veronika S. Georgieva
- Experimental
Neonatology, Department of Pediatrics and Adolescent Medicine, University of Cologne, Cologne 50939, Germany
- Center
for Biochemistry, Medical Faculty, University
of Cologne, Cologne 50923, Germany
| | - Shiyi Chen
- Department
of Chemistry, Institute of Inorganic Chemistry, University of Cologne, Cologne 50939, Germany
| | - Silvia Farè
- Department
of Chemistry, Materials and Chemical Engineering, Politecnico di Milano, Milano 20054, Italy
| | - Bent Brachvogel
- Experimental
Neonatology, Department of Pediatrics and Adolescent Medicine, University of Cologne, Cologne 50939, Germany
- Center
for Biochemistry, Medical Faculty, University
of Cologne, Cologne 50923, Germany
| | - Sanjay Mathur
- Department
of Chemistry, Institute of Inorganic Chemistry, University of Cologne, Cologne 50939, Germany
| | - Hajar Maleki
- Department
of Chemistry, Institute of Inorganic Chemistry, University of Cologne, Cologne 50939, Germany
- Center
for Molecular Medicine Cologne, CMMC Research Center, Robert-Koch-Str. 21, Cologne 50931, Germany
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3
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Egorov PA, Grishanov DA, Medvedev AG, Churakov AV, Mikhaylov AA, Ottenbacher RV, Bryliakov KP, Babak MV, Lev O, Prikhodchenko PV. Organoantimony Dihydroperoxides: Synthesis, Crystal Structures, and Hydrogen Bonding Networks. Inorg Chem 2023. [PMID: 37311066 DOI: 10.1021/acs.inorgchem.3c00929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Despite growing interest in the potential applications of p-block hydroperoxo complexes, the chemistry of inorganic hydroperoxides remains largely unexplored. For instance, single-crystal structures of antimony hydroperoxo complexes have not been reported to date. Herein, we present the synthesis of six triaryl and trialkylantimony dihydroperoxides [Me3Sb(OOH)2, Me3Sb(OOH)2·H2O, Ph3Sb(OOH)2·0.75(C4H8O), Ph3Sb(OOH)2·2CH3OH, pTol3Sb(OOH)2, pTol3Sb(OOH)2·2(C4H8O)], obtained by the reaction of the corresponding dibromide antimony(V) complexes with an excess of highly concentrated hydrogen peroxide in the presence of ammonia. The obtained compounds were characterized by single-crystal and powder X-ray diffraction, Fourier transform infrared and Raman spectroscopies, and thermal analysis. The crystal structures of all six compounds reveal hydrogen-bonded networks formed by hydroperoxo ligands. In addition to the previously reported double hydrogen bonding, new types of hydrogen-bonded motifs formed by hydroperoxo ligands were found, including infinite hydroperoxo chains. Solid-state density functional theory calculation of Me3Sb(OOH)2 revealed reasonably strong hydrogen bonding between OOH ligands with an energy of 35 kJ/mol. Additionally, the potential application of Ph3Sb(OOH)2·0.75(C4H8O) as a two-electron oxidant for the enantioselective epoxidation of olefins was investigated in comparison with Ph3SiOOH, Ph3PbOOH, t-BuOOH, and H2O2.
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Affiliation(s)
- Pavel A Egorov
- Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninskii pr. 31, Moscow 119991, Russian Federation
| | - Dmitry A Grishanov
- Casali Center of Applied Chemistry, Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Alexander G Medvedev
- Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninskii pr. 31, Moscow 119991, Russian Federation
| | - Andrei V Churakov
- Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninskii pr. 31, Moscow 119991, Russian Federation
| | - Alexey A Mikhaylov
- Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninskii pr. 31, Moscow 119991, Russian Federation
| | - Roman V Ottenbacher
- Boreskov Institute of Catalysis, Pr. Lavrentieva 5, Novosibirsk 630090, Russian Federation
| | - Konstantin P Bryliakov
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninskii pr. 47, Moscow 119991, Russian Federation
| | - Maria V Babak
- Drug Discovery Lab, Department of Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR 999077, China
| | - Ovadia Lev
- Casali Center of Applied Chemistry, Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Petr V Prikhodchenko
- Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninskii pr. 31, Moscow 119991, Russian Federation
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4
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Hern M, Foley R, Bacsa J, Wallen CM. Binding polyprotic small molecules with second-sphere hydrogen bonds. J COORD CHEM 2022. [DOI: 10.1080/00958972.2022.2119850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Affiliation(s)
- Morgan Hern
- Department of Chemistry and Fermentation Sciences, Appalachian State University, Boone, NC, USA
| | - Rebecca Foley
- Department of Chemistry and Fermentation Sciences, Appalachian State University, Boone, NC, USA
| | - John Bacsa
- Department of Chemistry, Emory University, Atlanta, GA, USA
| | - Christian M. Wallen
- Department of Chemistry and Fermentation Sciences, Appalachian State University, Boone, NC, USA
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5
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Carsch KM, Iliescu A, McGillicuddy RD, Mason JA, Betley TA. Reversible Scavenging of Dioxygen from Air by a Copper Complex. J Am Chem Soc 2021; 143:18346-18352. [PMID: 34672573 DOI: 10.1021/jacs.1c10254] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report that exposing the dipyrrin complex (EMindL)Cu(N2) to air affords rapid, quantitative uptake of O2 in either solution or the solid-state to yield (EMindL)Cu(O2). The air and thermal stability of (EMindL)Cu(O2) is unparalleled in molecular copper-dioxygen coordination chemistry, attributable to the ligand flanking groups which preclude the [Cu(O2)]1+ core from degradation. Despite the apparent stability of (EMindL)Cu(O2), dioxygen binding is reversible over multiple cycles with competitive solvent exchange, thermal cycling, and redox manipulations. Additionally, rapid, catalytic oxidation of 1,2-diphenylhydrazine to azoarene with the generation of hydrogen peroxide is observed, through the intermittency of an observable (EMindL)Cu(H2O2) adduct. The design principles gleaned from this study can provide insight for the formation of new materials capable of reversible scavenging of O2 from air under ambient conditions with low-coordinate CuI sorbents.
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Affiliation(s)
- Kurtis M Carsch
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Andrei Iliescu
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Ryan D McGillicuddy
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Jarad A Mason
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Theodore A Betley
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
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6
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Salaam J, Pilet G, Hasserodt J. Multiple Sulfonation of Picolyl-Based Complexes Rendering Them Highly Water-Compatible. Inorg Chem 2020; 59:13812-13816. [DOI: 10.1021/acs.inorgchem.0c02017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jeremy Salaam
- Laboratoire de Chimie, UMR 5182, CNRS, Ecolé Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, Université de Lyon, Lyon 69177, France
| | - Guillaume Pilet
- Laboratoire des Multimatériaux et Interfaces, UMR 5615, CNRS, Université Claude Bernard Lyon 1, Université de Lyon, Lyon 69177, France
| | - Jens Hasserodt
- Laboratoire de Chimie, UMR 5182, CNRS, Ecolé Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, Université de Lyon, Lyon 69177, France
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7
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Oloyede HO, Woods JAO, Görls H, Plass W, Eseola AO. New cobalt( ii) coordination designs and the influence of varying chelate characters, ligand charges and incorporated group I metal ions on enzyme-like oxidative coupling activity. NEW J CHEM 2020. [DOI: 10.1039/d0nj02347g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In transition-metal-mediated catalysis, design of new, well defined coordination architectures and subjecting them to catalysis testing under the same reaction conditions is a necessity tool for improved understanding of desirable active site geometries and characteristics.
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Affiliation(s)
| | | | - Helmar Görls
- Institut für Anorganische und Analytische Chemie
- Friedrich-Schiller-Universität Jena
- 07743 Jena
- Germany
| | - Winfried Plass
- Institut für Anorganische und Analytische Chemie
- Friedrich-Schiller-Universität Jena
- 07743 Jena
- Germany
| | - Abiodun Omokehinde Eseola
- Institut für Anorganische und Analytische Chemie
- Friedrich-Schiller-Universität Jena
- 07743 Jena
- Germany
- Materials Chemistry Group
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8
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Sampson J, Choi G, Akhtar MN, Jaseer E, Theravalappil R, Garcia N, Agapie T. Early Metal Di(pyridyl) Pyrrolide Complexes with Second Coordination Sphere Arene-π Interactions: Ligand Binding and Ethylene Polymerization. ACS OMEGA 2019; 4:15879-15892. [PMID: 31592458 PMCID: PMC6776977 DOI: 10.1021/acsomega.9b01788] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 08/27/2019] [Indexed: 05/04/2023]
Abstract
Early metal complexes supported by hemilabile, monoanionic di(pyridyl) pyrrolide ligands substituted with mesityl and anthracenyl groups were synthesized to probe the possibility of second coordination sphere arene-π interactions with ligands with potential for allosteric control in coordination chemistry, substrate activation, and olefin polymerization. Yttrium alkyl, indolide, and amide complexes were prepared and structurally characterized; close contacts between the anthracenyl substituents and Y-bound ligands are observed in the solid state. Titanium, zirconium, and hafnium tris(dimethylamido) complexes were synthesized, and their ethylene polymerization activity was tested. In the solid state structure of one of the Ti tris(dimethylamido) complexes, coordination of Ti to only one of the pyridine donors is observed pointing to the hemilabile character of the di(pyridyl) pyrrolide ligands.
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Affiliation(s)
- Jessica Sampson
- Division
of Chemistry and Chemical Engineering, California
Institute of Technology, 1200 E California Blvd., Pasadena, California 91125, United States
| | - Gyeongshin Choi
- Division
of Chemistry and Chemical Engineering, California
Institute of Technology, 1200 E California Blvd., Pasadena, California 91125, United States
| | - Muhammed Naseem Akhtar
- Center
for Refining and Petrochemicals, King Fahd
University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
| | - E.A. Jaseer
- Center
for Refining and Petrochemicals, King Fahd
University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
| | - Rajesh Theravalappil
- Center
for Refining and Petrochemicals, King Fahd
University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
| | - Nestor Garcia
- Center
for Refining and Petrochemicals, King Fahd
University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
| | - Theodor Agapie
- Division
of Chemistry and Chemical Engineering, California
Institute of Technology, 1200 E California Blvd., Pasadena, California 91125, United States
- E-mail:
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9
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Wang YH, Schneider PE, Goldsmith ZK, Mondal B, Hammes-Schiffer S, Stahl SS. Brønsted Acid Scaling Relationships Enable Control Over Product Selectivity from O 2 Reduction with a Mononuclear Cobalt Porphyrin Catalyst. ACS CENTRAL SCIENCE 2019; 5:1024-1034. [PMID: 31263762 PMCID: PMC6598176 DOI: 10.1021/acscentsci.9b00194] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Indexed: 05/11/2023]
Abstract
The selective reduction of O2, typically with the goal of forming H2O, represents a long-standing challenge in the field of catalysis. Macrocyclic transition-metal complexes, and cobalt porphyrins in particular, have been the focus of extensive study as catalysts for this reaction. Here, we show that the mononuclear Co-tetraarylporphyrin complex, Co(porOMe) (porOMe = meso-tetra(4-methoxyphenyl)porphyrin), catalyzes either 2e-/2H+ or 4e-/4H+ reduction of O2 with high selectivity simply by changing the identity of the Brønsted acid in dimethylformamide (DMF). The thermodynamic potentials for O2 reduction to H2O2 or H2O in DMF are determined and exhibit a Nernstian dependence on the acid pK a, while the CoIII/II redox potential is independent of the acid pK a. The reaction product, H2O or H2O2, is defined by the relationship between the thermodynamic potential for O2 reduction to H2O2 and the CoIII/II redox potential: selective H2O2 formation is observed when the CoIII/II potential is below the O2/H2O2 potential, while H2O formation is observed when the CoIII/II potential is above the O2/H2O2 potential. Mechanistic studies reveal that the reactions generating H2O2 and H2O exhibit different rate laws and catalyst resting states, and these differences are manifested as different slopes in linear free energy correlations between the log(rate) versus pK a and log(rate) versus effective overpotential for the reactions. This work shows how scaling relationships may be used to control product selectivity, and it provides a mechanistic basis for the pursuit of molecular catalysts that achieve low overpotential reduction of O2 to H2O.
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Affiliation(s)
- Yu-Heng Wang
- Department
of Chemistry, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
| | - Patrick E. Schneider
- Department
of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Zachary K. Goldsmith
- Department
of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Biswajit Mondal
- Department
of Chemistry, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
| | - Sharon Hammes-Schiffer
- Department
of Chemistry, Yale University, New Haven, Connecticut 06520, United States
- E-mail:
| | - Shannon S. Stahl
- Department
of Chemistry, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
- E-mail:
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10
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Nurdin L, Spasyuk DM, Fairburn L, Piers WE, Maron L. Oxygen-Oxygen Bond Cleavage and Formation in Co(II)-Mediated Stoichiometric O 2 Reduction via the Potential Intermediacy of a Co(IV) Oxyl Radical. J Am Chem Soc 2018; 140:16094-16105. [PMID: 30398331 DOI: 10.1021/jacs.8b07726] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In reactions of significance to alternative energy schemes, metal catalysts are needed to overcome kinetically and thermodynamically difficult processes. Often, high-oxidation-state, high-energy metal oxo intermediates are proposed as mediators in elementary steps involving O-O bond cleavage and formation, but the mechanisms of these steps are difficult to study because of the fleeting nature of these species. Here we utilized a novel dianionic pentadentate ligand system that enabled a detailed mechanistic investigation of the protonation of a cobalt(III)-cobalt(III) peroxo dimer, a known intermediate in oxygen reduction catalysis to hydrogen peroxide. It was shown that double protonation occurs rapidly and leads to a low-energy O-O bond cleavage step that generates a Co(III) aquo complex and a highly reactive Co(IV) oxyl cation. The latter was probed computationally and experimentally implicated through chemical interception and isotope labeling experiments. In the absence of competing chemical reagents, it dimerizes and eliminates dioxygen in a step highly relevant to O-O bond formation in the oxygen evolution step in water oxidation. Thus, the study demonstrates both facile O-O bond cleavage and formation in the stoichiometric reduction of O2 to H2O with 2 equiv of Co(II) and suggests a new pathway for selective reduction of O2 to water via Co(III)-O-O-Co(III) peroxo intermediates.
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Affiliation(s)
- Lucie Nurdin
- Department of Chemistry , University of Calgary , 2500 University Drive NW , Calgary , Alberta T2N 1N4 , Canada
| | - Denis M Spasyuk
- Department of Chemistry , University of Calgary , 2500 University Drive NW , Calgary , Alberta T2N 1N4 , Canada
| | - Laura Fairburn
- Department of Chemistry , University of Calgary , 2500 University Drive NW , Calgary , Alberta T2N 1N4 , Canada
| | - Warren E Piers
- Department of Chemistry , University of Calgary , 2500 University Drive NW , Calgary , Alberta T2N 1N4 , Canada
| | - Laurent Maron
- LPCNO, Université de Toulouse, INSA, UPS, LPCNO , 135 avenue de Rangueil , F-31077 Toulouse , France , and CNRS, LPCNO, F-31077 Toulouse, France
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