1
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Dey A, Albert T, Kong RY, Macmillan SN, Moënne-Loccoz P, Lancaster KM, Goldberg DP. Direct Reduction of NO to N 2O by a Mononuclear Nonheme Thiolate Ligated Iron(II) Complex via Formation of a Metastable {FeNO} 7 Complex. Inorg Chem 2022; 61:14909-14917. [PMID: 36107151 PMCID: PMC9555345 DOI: 10.1021/acs.inorgchem.2c02383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Addition of NO to a nonheme dithiolate-ligated iron(II) complex, FeII(Me3TACN)(S2SiMe2) (1), results in the generation of N2O. Low-temperature spectroscopic studies reveal a metastable six-coordinate {FeNO}7 intermediate (S = 3/2) that was trapped at -135 °C and was characterized by low-temperature UV-vis, resonance Raman, EPR, Mössbauer, XAS, and DFT studies. Thermal decay of the {FeNO}7 species leads to the evolution of N2O, providing a rare example of a mononuclear thiolate-ligated {FeNO}7 that mediates NO reduction to N2O without the requirement of any exogenous electron or proton sources.
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Affiliation(s)
- Aniruddha Dey
- Department of Chemistry, The Johns Hopkins University, Baltimore, MD 21218, United States
| | - Therese Albert
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR 97239, Unites States
| | - Richard Y. Kong
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, Unites States
| | - Samantha N. Macmillan
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, Unites States
| | - Pierre Moënne-Loccoz
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR 97239, Unites States
| | - Kyle M. Lancaster
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, Unites States
| | - David P. Goldberg
- Department of Chemistry, The Johns Hopkins University, Baltimore, MD 21218, United States
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2
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Lehnert N, Kim E, Dong HT, Harland JB, Hunt AP, Manickas EC, Oakley KM, Pham J, Reed GC, Alfaro VS. The Biologically Relevant Coordination Chemistry of Iron and Nitric Oxide: Electronic Structure and Reactivity. Chem Rev 2021; 121:14682-14905. [PMID: 34902255 DOI: 10.1021/acs.chemrev.1c00253] [Citation(s) in RCA: 92] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Nitric oxide (NO) is an important signaling molecule that is involved in a wide range of physiological and pathological events in biology. Metal coordination chemistry, especially with iron, is at the heart of many biological transformations involving NO. A series of heme proteins, nitric oxide synthases (NOS), soluble guanylate cyclase (sGC), and nitrophorins, are responsible for the biosynthesis, sensing, and transport of NO. Alternatively, NO can be generated from nitrite by heme- and copper-containing nitrite reductases (NIRs). The NO-bearing small molecules such as nitrosothiols and dinitrosyl iron complexes (DNICs) can serve as an alternative vehicle for NO storage and transport. Once NO is formed, the rich reaction chemistry of NO leads to a wide variety of biological activities including reduction of NO by heme or non-heme iron-containing NO reductases and protein post-translational modifications by DNICs. Much of our understanding of the reactivity of metal sites in biology with NO and the mechanisms of these transformations has come from the elucidation of the geometric and electronic structures and chemical reactivity of synthetic model systems, in synergy with biochemical and biophysical studies on the relevant proteins themselves. This review focuses on recent advancements from studies on proteins and model complexes that not only have improved our understanding of the biological roles of NO but also have provided foundations for biomedical research and for bio-inspired catalyst design in energy science.
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Affiliation(s)
- Nicolai Lehnert
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Eunsuk Kim
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Hai T Dong
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Jill B Harland
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Andrew P Hunt
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Elizabeth C Manickas
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Kady M Oakley
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - John Pham
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Garrett C Reed
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Victor Sosa Alfaro
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
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3
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Dey A, Gordon JB, Albert T, Sabuncu S, Siegler MA, MacMillan SN, Lancaster KM, Moënne‐Loccoz P, Goldberg DP. A Nonheme Mononuclear {FeNO}
7
Complex that Produces N
2
O in the Absence of an Exogenous Reductant. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202109062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Aniruddha Dey
- Department of Chemistry The Johns Hopkins University Baltimore MD 21218 USA
| | - Jesse B. Gordon
- Department of Chemistry The Johns Hopkins University Baltimore MD 21218 USA
| | - Therese Albert
- Department of Chemical Physiology and Biochemistry Oregon Health & Science University Portland OR 97239 USA
| | - Sinan Sabuncu
- Department of Chemical Physiology and Biochemistry Oregon Health & Science University Portland OR 97239 USA
| | - Maxime A. Siegler
- Department of Chemistry The Johns Hopkins University Baltimore MD 21218 USA
| | | | - Kyle M. Lancaster
- Department of Chemistry and Chemical Biology Cornell University Ithaca NY 14853 USA
| | - Pierre Moënne‐Loccoz
- Department of Chemical Physiology and Biochemistry Oregon Health & Science University Portland OR 97239 USA
| | - David P. Goldberg
- Department of Chemistry The Johns Hopkins University Baltimore MD 21218 USA
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4
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Dey A, Gordon JB, Albert T, Sabuncu S, Siegler MA, MacMillan SN, Lancaster KM, Moënne-Loccoz P, Goldberg DP. A Nonheme Mononuclear {FeNO} 7 Complex that Produces N 2 O in the Absence of an Exogenous Reductant. Angew Chem Int Ed Engl 2021; 60:21558-21564. [PMID: 34415659 DOI: 10.1002/anie.202109062] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Indexed: 11/09/2022]
Abstract
A new nonheme iron(II) complex, FeII (Me3 TACN)((OSiPh2 )2 O) (1), is reported. Reaction of 1 with NO(g) gives a stable mononitrosyl complex Fe(NO)(Me3 TACN)((OSiPh2 )2 O) (2), which was characterized by Mössbauer (δ=0.52 mm s-1 , |ΔEQ |=0.80 mm s-1 ), EPR (S=3/2), resonance Raman (RR) and Fe K-edge X-ray absorption spectroscopies. The data show that 2 is an {FeNO}7 complex with an S=3/2 spin ground state. The RR spectrum (λexc =458 nm) of 2 combined with isotopic labeling (15 N, 18 O) reveals ν(N-O)=1680 cm-1 , which is highly activated, and is a nearly identical match to that seen for the reactive mononitrosyl intermediate in the nonheme iron enzyme FDPnor (ν(NO)=1681 cm-1 ). Complex 2 reacts rapidly with H2 O in THF to produce the N-N coupled product N2 O, providing the first example of a mononuclear nonheme iron complex that is capable of converting NO to N2 O in the absence of an exogenous reductant.
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Affiliation(s)
- Aniruddha Dey
- Department of Chemistry, The Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Jesse B Gordon
- Department of Chemistry, The Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Therese Albert
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Sinan Sabuncu
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Maxime A Siegler
- Department of Chemistry, The Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Samantha N MacMillan
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - Pierre Moënne-Loccoz
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, 97239, USA
| | - David P Goldberg
- Department of Chemistry, The Johns Hopkins University, Baltimore, MD, 21218, USA
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5
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Lin S, He C. Development of Nonheme {FeNO} 7 Complexes Based on the Pyrococcus furiosus Rubredoxin for Red-Light-Controllable Nitric Oxide Release. Inorg Chem 2021; 60:14364-14370. [PMID: 34503329 DOI: 10.1021/acs.inorgchem.1c02089] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Nitric oxide (NO) is an essential biological messenger, contributing a significant role in a diverse range of physiological processes. The light-controllable NO releasers are of great interest because of their potential as agents for NO-related research and therapeutics. Herein, we developed a pair of red-light-controllable NO releasers, pfRd-C9A-{FeNO}7 and pfRd-C42A-{FeNO}7 (pfRd = Pyrococcus furiosus rubredoxin), by constructing a nonheme {FeNO}7 center within the redesigned iron-sulfur protein scaffolds. While shown to be both air and thermally stable, these complexes are highly sensitive to red-light irradiation with temporal precision, which was confirmed by electron paramagnetic resonance spin trapping and Griess assay. The temporally controlled NO release from these complexes was also demonstrated in DNA cleavage assay. Overall, this study demonstrates that such a protein-based nonheme iron nitrosyl system could be a viable chemical tool for precise NO administration.
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Affiliation(s)
- Shaomin Lin
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China
| | - Chunmao He
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China
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6
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Pal N, White CJ, Demeshko S, Meyer F, Lehnert N, Majumdar A. A Monohydrosulfidodinitrosyldiiron Complex That Generates N 2O as a Model for Flavodiiron Nitric Oxide Reductases: Reaction Mechanism and Electronic Structure. Inorg Chem 2021; 60:15890-15900. [PMID: 34106714 DOI: 10.1021/acs.inorgchem.1c00429] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Flavodiiron nitric oxide reductases (FNORs) protect microbes from nitrosative stress under anaerobic conditions by mediating the reduction of nitric oxide (NO) to nitrous oxide (N2O). The proposed mechanism for the catalytic reduction of NO by FNORs involves a dinitrosyldiiron intermediate with a [hs-{FeNO}7]2 formulation, which produces N2O and a diferric species. Moreover, both NO and hydrogen sulfide (H2S) have been implicated in several similar physiological functions in biology and are also known to cross paths in cell signaling. Here we report the synthesis, spectroscopic and theoretical characterization, and N2O production activity of an unprecedented monohydrosulfidodinitrosyldiiron compound, with a [(HS)hs-{FeNO}7/hs-{FeNO}7] formulation, that models the key dinitrosyl intermediate of FNORs. The generation of N2O from this unique compound follows a semireduced pathway, where one-electron reduction generates a reactive hs-{FeNO}8 center via the occupation of an Fe-NO antibonding orbital. In contrast to the well-known reactivity of H2S and NO, the coordinated hydrosulfide remains unreactive toward NO and acts only as a spectator ligand during the NO reduction process.
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Affiliation(s)
- Nabhendu Pal
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Kolkata 700032, West Bengal, India
| | - Corey J White
- Department of Chemistry, The University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Serhiy Demeshko
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstraße 4, Göttingen 37077, Germany
| | - Franc Meyer
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstraße 4, Göttingen 37077, Germany
| | - Nicolai Lehnert
- Department of Chemistry, The University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Amit Majumdar
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Kolkata 700032, West Bengal, India
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7
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Poptic AL, Zhang S. Iron(II/III) Halide Complexes Promote the Interconversion of Nitric Oxide and S-Nitrosothiols through Reversible Fe-S Interaction. Inorg Chem 2021; 60:5190-5197. [PMID: 33705121 DOI: 10.1021/acs.inorgchem.1c00203] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Heme and non-heme iron in biology mediate the storage/release of NO• from S-nitrosothiols as a means to control the biological concentration of NO•. Despite their importance in many physiological processes, the mechanisms of N-S bond formation/cleavage at Fe centers have been controversial. Herein, we report the interconversion of NO• and S-nitrosothiols mediated by FeII/FeIII chloride complexes. The reaction of 2 equiv of S-nitrosothiol (Ph3CSNO) with [Cl6FeII2]2- results in facile release of NO• and formation of iron(III) halothiolate. Detailed spectroscopic studies, including in situ UV-vis, IR, and Mössbauer spectroscopy, support the interaction of the S atom with the FeII center. This is in contrast to the proposed mechanism of NO• release from the well-studied "red product" κ1-N bound S-nitrosothiol FeII complex, [(CN)5Fe(κ1-N-RSNO)]3-. Additionally, FeIII chloride can mediate NO• storage through the formation of S-nitrosothiols. Treatment of iron(III) halothiolate with 2 equiv of NO• regenerates Ph3CSNO with the FeII source trapped as the S = 3/2 {FeNO}7 species [Cl3FeNO]-, which is inert toward further coordination and activation of S-nitrosothiols. Our work demonstrates how labile iron can mediate the interconversion of NO•/thiolate and S-nitrosothiol, which has important implications toward how Nature manages the biological concentration of free NO•.
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Affiliation(s)
- Anna L Poptic
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Shiyu Zhang
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
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8
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Ekanayake DM, Fischer AA, Elwood ME, Guzek AM, Lindeman SV, Popescu CV, Fiedler AT. Nonheme iron-thiolate complexes as structural models of sulfoxide synthase active sites. Dalton Trans 2020; 49:17745-17757. [PMID: 33241840 PMCID: PMC7781232 DOI: 10.1039/d0dt03403g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Two mononuclear iron(ii)-thiolate complexes have been prepared that represent structural models of the nonheme iron enzymes EgtB and OvoA, which catalyze the O2-dependent formation of carbon-sulfur bonds in the biosynthesis of thiohistidine compounds. The series of Fe(ii) complexes reported here feature tripodal N4 chelates (LA and LB) that contain both pyridyl and imidazolyl donors (LA = (1H-imidazol-4-yl)-N,N-bis((pyridin-2-yl)methyl)methanamine; LB = N,N-bis((1-methylimidazol-2-yl)methyl)-2-pyridylmethylamine). Further coordination with monodentate aromatic or aliphatic thiolate ligands yielded the five-coordinate, high-spin Fe(ii) complexes [FeII(LA)(SMes)]BPh4 (1) and [FeII(LB)(SCy)]BPh4 (2), where SMes = 2,4,6-trimethylthiophenolate and SCy = cyclohexanethiolate. X-ray crystal structures revealed that 1 and 2 possess trigonal bipyramidal geometries formed by the N4S ligand set. In each case, the thiolate ligand is positioned cis to an imidazole donor, replicating the arrangement of Cys- and His-based substrates in the active site of EgtB. The geometric and electronic structures of 1 and 2 were analyzed with UV-vis absorption and Mössbauer spectroscopies in tandem with density functional theory (DFT) calculations. Exposure of 1 and 2 to nitric oxide (NO) yielded six-coordinate FeNO adducts that were characterized with infrared and electron paramagnetic resonance (EPR) spectroscopies, confirming that these complexes are capable of binding diatomic molecules. Reaction of 1 and 2 with O2 causes oxidation of the thiolate ligands to disulfide products. The implications of these results for the development of functional models of EgtB and OvoA are discussed.
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9
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Chiang CK, Chu KT, Lin CC, Xie SR, Liu YC, Demeshko S, Lee GH, Meyer F, Tsai ML, Chiang MH, Lee CM. Photoinduced NO and HNO Production from Mononuclear {FeNO}6 Complex Bearing a Pendant Thiol. J Am Chem Soc 2020; 142:8649-8661. [DOI: 10.1021/jacs.9b13837] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Chuan-Kuei Chiang
- Department of Applied Science, National Taitung University, Taitung 950, Taiwan
| | - Kai-Ti Chu
- Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan
| | - Chia-Chin Lin
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung 804, Taiwan
| | - Shi-Rou Xie
- Department of Applied Science, National Taitung University, Taitung 950, Taiwan
| | - Yu-Chiao Liu
- Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan
| | - Serhiy Demeshko
- Universität Göttingen, Institut für Anorganische Chemie, Tammannstraße 4, D-37077 Göttingen, Germany
| | - Gene-Hsiang Lee
- Instrumentation Center, National Taiwan University, Taipei 107, Taiwan
| | - Franc Meyer
- Universität Göttingen, Institut für Anorganische Chemie, Tammannstraße 4, D-37077 Göttingen, Germany
| | - Ming-Li Tsai
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung 804, Taiwan
- Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 807, Taiwan
| | - Ming-Hsi Chiang
- Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan
- Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 807, Taiwan
| | - Chien-Ming Lee
- Department of Applied Science, National Taitung University, Taitung 950, Taiwan
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10
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Shin JW, Jeong AR, Jeong JH, Zenno H, Hayami S, Min KS. Two-dimensional square-grid iron(ii) coordination polymers showing anion-dependent spin crossover behavior. RSC Adv 2020; 10:5040-5049. [PMID: 35498313 PMCID: PMC9049044 DOI: 10.1039/c9ra09782a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 01/24/2020] [Indexed: 11/21/2022] Open
Abstract
Two Fe(ii)-based coordination polymers [Fe(tpmd)2(NCS)2]·5.5H2O (1) and [Fe(tpmd)2(NCSe)2]·7H2O (2) with the framework of square-grid type have been assembled from FeSO4·7H2O, N,N,N′,N′-tetrakis(pyridin-4-yl)methanediamine (tpmd), and KNCS/KNCSe in methanol and characterized. By utilizing two pyridine groups of a tpmd ligand, 1 and 2 are formed in two-dimensional layered structures through coordination of octahedral iron(ii) ions with the tpmd to NCS−/NCSe− ligands in which they have a supramolecular isomorphous conformation. 1 shows a paramagnetic behavior between 2 and 300 K, while 2 exhibits two-step spin crossover (ca. 145 and 50 K) in the temperature range due to the coordination of NCSe− ligands. At 300 K 2 is fully high-spin state. However, at 100 K 2 becomes ca. 50% high spin and 50% low spin iron(ii) ions, which is verified by magnetic moments. In the structural analysis of 2 at 100 K, two different layers are observed with different bond distances around iron(ii) ions in which the layers are stacked alternately. Two-dimensional Fe-based coordination polymers with square-grid shapes were prepared by self-assembly and exhibited an interesting spin crossover behavior depending on the coordinated counter ions.![]()
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Affiliation(s)
- Jong Won Shin
- Department of Chemistry
- Kyungpook National University
- Daegu 41566
- Republic of Korea
| | - Ah Rim Jeong
- Department of Chemistry
- Kyungpook National University
- Daegu 41566
- Republic of Korea
| | - Jong Hwa Jeong
- Department of Chemistry
- Kyungpook National University
- Daegu 41566
- Republic of Korea
| | - Hikaru Zenno
- Department of Chemistry
- Kumamoto University
- Kumamoto 860-8555
- Japan
| | - Shinya Hayami
- Department of Chemistry
- Kumamoto University
- Kumamoto 860-8555
- Japan
| | - Kil Sik Min
- Department of Chemistry Education
- Kyungpook National University
- Daegu 41566
- Republic of Korea
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11
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Confer AM, Sabuncu S, Siegler MA, Moënne-Loccoz P, Goldberg DP. Mononuclear, Nonheme, High-Spin {FeNO} 7/8 Complexes Supported by a Sterically Encumbered N 4S-Thioether Ligand. Inorg Chem 2019; 58:9576-9580. [PMID: 31328501 DOI: 10.1021/acs.inorgchem.9b01475] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The synthesis of a new nonheme iron NO binding complex, [FeII(CH3CN)(N3Py2PhSEtCN)](BF4)2 (1), is reported. Complex 1, which contains two sterically encumbering phenyl substituents, exhibits a high-spin (hs) FeII (S = 2) ground state in contrast to the S = 0 ground state for unsubstituted [FeII(CH3CN)(N3PySEtCN)(BF4)2. Reaction of 1 with NO(g) in CH3CN yields an {FeNO}7 (S = 3/2) complex 2, which slowly decays at 25 °C with loss of NO• to regenerate 1. One-electron reduction of 2 with Cr(C6H6)2 at -40 °C yields the metastable, S = 1 {FeNO}8 complex 3. The nitrosyl moieties in thioether-ligated 2 and 3 are significantly less activated than in thiolate-ligated [Fe(NO)(N3PyS)]+/0, a structurally analogous pair of hs {FeNO}7/8 complexes. Calculations reveal that reduction of 2 is iron-centered, which may be a general property of hs {FeNO}7/8 complexes.
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Affiliation(s)
- Alex M Confer
- Department of Chemistry , The Johns Hopkins University , Baltimore , Maryland 21218 , United States
| | - Sinan Sabuncu
- Department of Biochemistry & Molecular Biology , Oregon Health & Science University , Portland , Oregon 97239 , United States
| | - Maxime A Siegler
- Department of Chemistry , The Johns Hopkins University , Baltimore , Maryland 21218 , United States
| | - Pierre Moënne-Loccoz
- Department of Biochemistry & Molecular Biology , Oregon Health & Science University , Portland , Oregon 97239 , United States
| | - David P Goldberg
- Department of Chemistry , The Johns Hopkins University , Baltimore , Maryland 21218 , United States
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12
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Confer AM, Vilbert AC, Dey A, Lancaster KM, Goldberg DP. A Mononuclear, Nonheme Fe II-Piloty's Acid (PhSO 2NHOH) Adduct: An Intermediate in the Production of {FeNO} 7/8 Complexes from Piloty's Acid. J Am Chem Soc 2019; 141:7046-7055. [PMID: 30994347 DOI: 10.1021/jacs.9b01700] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Reaction of the mononuclear nonheme complex [FeII(CH3CN)(N3PyS)]BF4 (1) with an HNO donor, Piloty's acid (PhSO2NHOH, P.A.), at low temperature affords a high-spin ( S = 2) FeII-P.A. intermediate (2), characterized by 57Fe Mössbauer and Fe K-edge X-ray absorption (XAS) spectroscopies, with interpretation of both supported by DFT calculations. The combined methods indicate that P.A. anion binds as the N-deprotonated tautomer (PhSO2NOH-) to [FeII(N3PyS)]+, leading to 2. Complex 2 is the first spectroscopically characterized example, to our knowledge, of P.A. anion bound to a redox-active metal center. Warming of 2 above -60 °C yields the stable {FeNO}7 complex [Fe(NO)(N3PyS)]BF4 (4), as evidenced by 1H NMR, ATR-IR, and Mössbauer spectroscopies. Isotope labeling experiments with 15N-labeled P.A. confirm that the nitrosyl ligand in 4 derives from P.A. In contrast, addition of a second equivalent of a strong base leads to S-N cleavage and production of an {FeNO}8 species, the deprotonated analog of an Fe-HNO complex. This work has implications for the targeted delivery of HNO/NO-/NO· to nonheme Fe centers in biological and synthetic applications, and suggests a new role for nonheme FeII complexes in the assisted degradation of HNO donor molecules.
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Affiliation(s)
- Alex M Confer
- Department of Chemistry , The Johns Hopkins University , Baltimore , Maryland 21218 , United States
| | - Avery C Vilbert
- Baker Laboratory, Department of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14853 , United States
| | - Aniruddha Dey
- Department of Chemistry , The Johns Hopkins University , Baltimore , Maryland 21218 , United States
| | - Kyle M Lancaster
- Baker Laboratory, Department of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14853 , United States
| | - David P Goldberg
- Department of Chemistry , The Johns Hopkins University , Baltimore , Maryland 21218 , United States
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13
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Wang L, Gennari M, Cantú Reinhard FG, Gutiérrez J, Morozan A, Philouze C, Demeshko S, Artero V, Meyer F, de Visser SP, Duboc C. A Non-Heme Diiron Complex for (Electro)catalytic Reduction of Dioxygen: Tuning the Selectivity through Electron Delivery. J Am Chem Soc 2019; 141:8244-8253. [DOI: 10.1021/jacs.9b02011] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Lianke Wang
- Université Grenoble Alpes, CNRS UMR 5250, DCM, F-38000 Grenoble, France
| | - Marcello Gennari
- Université Grenoble Alpes, CNRS UMR 5250, DCM, F-38000 Grenoble, France
| | - Fabián G. Cantú Reinhard
- Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Javier Gutiérrez
- Université Grenoble Alpes, CNRS UMR 5250, DCM, F-38000 Grenoble, France
| | - Adina Morozan
- Université Grenoble Alpes, CNRS, CEA, Laboratoire de Chimie et
Biologie des Métaux, F-38000 Grenoble, France
| | | | - Serhiy Demeshko
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstrasse 4, D-37077 Göttingen, Germany
| | - Vincent Artero
- Université Grenoble Alpes, CNRS, CEA, Laboratoire de Chimie et
Biologie des Métaux, F-38000 Grenoble, France
| | - Franc Meyer
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstrasse 4, D-37077 Göttingen, Germany
| | - Sam P. de Visser
- Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Carole Duboc
- Université Grenoble Alpes, CNRS UMR 5250, DCM, F-38000 Grenoble, France
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14
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Banerjee A, Li J, Speelman AL, White CJ, Pawlak PL, Brennessel WW, Lehnert N, Chavez FA. A Structural Model for the Iron-Nitrosyl Adduct of Gentisate Dioxygenase. Eur J Inorg Chem 2018; 2018:4797-4804. [PMID: 32577096 DOI: 10.1002/ejic.201800992] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
We present the synthesis, properties, and characterization of [Fe(T1Et4iPrIP)(NO)(H2O)2](OTf)2 (1) (T1Et4iPrIP = Tris(1-ethyl-4-isopropyl-imidazolyl)phosphine) as a model for the nitrosyl adduct of gentisate 1,2-dioxygenase (GDO). The further characterization of [Fe(T1Et4iPrIP)(THF)(NO)(OTf)](OTf) (2) which was previously communicated (Inorg. Chem. 2014, 53, 5414) is also presented. The weighted average Fe-N-O angle of 162° for 1 is very close to linear (≥ 165°) for these types of complexes. The coordinated water ligands participate in hydrogen bonding interactions. The spectral properties (EPR, UV-vis, FTIR) for 1 are compared with 2 and found to be quite comparable. Complex 1 closely follows the relationship between the Fe-N-O angle and NO vibrational frequency which was previously identified for 6-coordinate {FeNO}7 complexes. Liquid FTIR studies on 2 indicate that the ν(NO) vibration position is sensitive to solvent shifting to lower energy (relative to the solid) in donor solvent THF and shifting to higher energy in dichloromethane. The basis for this behavior is discussed. The K eq for NO binding in 2 was calculated in THF and found to be 470 M-1. Density functional theory (DFT) studies on 1 indicate donation of electron density to the iron center from the π* orbitals of formally NO-. Such a donation accounts for the near linearity of the Fe-N-O bond and the large ν(NO) value of 1791 cm-1.
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Affiliation(s)
- Atanu Banerjee
- Department of Chemistry, Oakland University, Rochester, MI 48309-4477, USA
| | - Jia Li
- Department of Chemistry, Oakland University, Rochester, MI 48309-4477, USA
| | - Amy L Speelman
- Department of Chemistry, The University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Corey J White
- Department of Chemistry, The University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Piotr L Pawlak
- Department of Chemistry, Oakland University, Rochester, MI 48309-4477, USA
| | | | - Nicolai Lehnert
- Department of Chemistry, The University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Ferman A Chavez
- Department of Chemistry, Oakland University, Rochester, MI 48309-4477, USA
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15
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Dey A, Confer AM, Vilbert AC, Moënne-Loccoz P, Lancaster KM, Goldberg DP. A Nonheme Sulfur-Ligated {FeNO} 6 Complex and Comparison with Redox-Interconvertible {FeNO} 7 and {FeNO} 8 Analogues. Angew Chem Int Ed Engl 2018; 57:13465-13469. [PMID: 30125450 DOI: 10.1002/anie.201806146] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Indexed: 01/23/2023]
Abstract
A nonheme {FeNO}6 complex, [Fe(NO)(N3PyS)]2+ , was synthesized by reversible, one-electron oxidation of an {FeNO}7 analogue. This complex completes the first known series of sulfur-ligated {FeNO}6-8 complexes. All three {FeNO}6-8 complexes are readily interconverted by one-electron oxidation/reduction. A comparison of spectroscopic data (UV/Vis, NMR, IR, Mössbauer, X-ray absorption) provides a complete picture of the electronic and structural changes that occur upon {FeNO}6 -{FeNO}8 interconversion. Dissociation of NO from the new {FeNO}6 complex is shown to be controlled by solvent, temperature, and photolysis, which is rare for a sulfur-ligated {FeNO}6 species.
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Affiliation(s)
- Aniruddha Dey
- Department of Chemistry, The Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Alex M Confer
- Department of Chemistry, The Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Avery C Vilbert
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - Pierre Moënne-Loccoz
- Division of Environmental and Biomolecular Systems, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - David P Goldberg
- Department of Chemistry, The Johns Hopkins University, Baltimore, MD, 21218, USA
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16
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Dey A, Confer AM, Vilbert AC, Moënne‐Loccoz P, Lancaster KM, Goldberg DP. A Nonheme Sulfur‐Ligated {FeNO}
6
Complex and Comparison with Redox‐Interconvertible {FeNO}
7
and {FeNO}
8
Analogues. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201806146] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Aniruddha Dey
- Department of Chemistry The Johns Hopkins University Baltimore MD 21218 USA
| | - Alex M. Confer
- Department of Chemistry The Johns Hopkins University Baltimore MD 21218 USA
| | - Avery C. Vilbert
- Department of Chemistry and Chemical Biology Cornell University Ithaca NY 14853 USA
| | - Pierre Moënne‐Loccoz
- Division of Environmental and Biomolecular Systems Oregon Health and Science University Portland OR 97239 USA
| | - Kyle M. Lancaster
- Department of Chemistry and Chemical Biology Cornell University Ithaca NY 14853 USA
| | - David P. Goldberg
- Department of Chemistry The Johns Hopkins University Baltimore MD 21218 USA
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17
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Levin N, Perdoménico J, Bill E, Weyhermüller T, Slep LD. Pushing the photodelivery of nitric oxide to the visible: are {FeNO} 7 complexes good candidates? Dalton Trans 2017; 46:16058-16064. [PMID: 29119166 DOI: 10.1039/c7dt03142d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Photodelivery of NO requires stable compounds which can be made reactive by irradiation with (visible) light. Traditional {MNO}6 complexes require a substantial ligand design to shift their absorption spectra to the appropriate region of the electromagnetic spectrum. [Fe((CH2Py2)2Me[9]aneN3)(NO)](BF4)2 is a new {FeNO}7 octahedral coordination compound, which is thermally and air-stable in solution. Illumination with a 450 nm light source induces significant photodetachment of the coordinated NO (ϕNO = 0.52 mol einstein-1), suggesting that {FeNO}7 compounds can be in fact suitable compounds for therapeutic NO-photorelease.
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Affiliation(s)
- Natalia Levin
- Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, and INQUIMAE, Universidad de Buenos Aires - CONICET, Pabellón 2, 3er piso, Ciudad Universitaria, C1428EHA, Ciudad Autónoma de Buenos Aires, Argentina.
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18
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Confer AM, McQuilken AC, Matsumura H, Moënne-Loccoz P, Goldberg DP. A Nonheme, High-Spin {FeNO} 8 Complex that Spontaneously Generates N 2O. J Am Chem Soc 2017; 139:10621-10624. [PMID: 28749673 DOI: 10.1021/jacs.7b05549] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
One-electron reduction of [Fe(NO)-(N3PyS)]BF4 (1) leads to the production of the metastable nonheme {FeNO}8 complex, [Fe(NO)(N3PyS)] (3). Complex 3 is a rare example of a high-spin (S = 1) {FeNO}8 and is the first example, to our knowledge, of a mononuclear nonheme {FeNO}8 species that generates N2O. A second, novel route to 3 involves addition of Piloty's acid, an HNO donor, to an FeII precursor. This work provides possible new insights regarding the mechanism of nitric oxide reductases.
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Affiliation(s)
- Alex M Confer
- Department of Chemistry, Johns Hopkins University , Baltimore, Maryland 21218, United States
| | - Alison C McQuilken
- Department of Chemistry, Johns Hopkins University , Baltimore, Maryland 21218, United States
| | - Hirotoshi Matsumura
- Institute of Environmental Health, Oregon Health & Science University , Portland, Oregon 97239, United States
| | - Pierre Moënne-Loccoz
- Institute of Environmental Health, Oregon Health & Science University , Portland, Oregon 97239, United States
| | - David P Goldberg
- Department of Chemistry, Johns Hopkins University , Baltimore, Maryland 21218, United States
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19
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Fischer AA, Stracey N, Lindeman SV, Brunold TC, Fiedler AT. Synthesis, X-ray Structures, Electronic Properties, and O 2/NO Reactivities of Thiol Dioxygenase Active-Site Models. Inorg Chem 2016; 55:11839-11853. [PMID: 27801576 DOI: 10.1021/acs.inorgchem.6b01931] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Mononuclear non-heme iron complexes that serve as structural and functional mimics of the thiol dioxygenases (TDOs), cysteine dioxygenase (CDO) and cysteamine dioxygenase (ADO), have been prepared and characterized with crystallographic, spectroscopic, kinetic, and computational methods. The high-spin Fe(II) complexes feature the facially coordinating tris(4,5-diphenyl-1-methylimidazol-2-yl)phosphine (Ph2TIP) ligand that replicates the three histidine (3His) triad of the TDO active sites. Further coordination with bidentate l-cysteine ethyl ester (CysOEt) or cysteamine (CysAm) anions yielded five-coordinate (5C) complexes that resemble the substrate-bound forms of CDO and ADO, respectively. Detailed electronic-structure descriptions of the [Fe(Ph2TIP)(LS,N)]BPh4 complexes, where LS,N = CysOEt (1) or CysAm (2), were generated through a combination of spectroscopic techniques [electronic absorption, magnetic circular dichroism (MCD)] and density functional theory (DFT). Complexes 1 and 2 decompose in the presence of O2 to yield the corresponding sulfinic acid (RSO2H) products, thereby emulating the reactivity of the TDO enzymes and related complexes. Rate constants and activation parameters for the dioxygenation reactions were measured and interpreted with the aid of DFT calculations for O2-bound intermediates. Treatment of the TDO models with nitric oxide (NO)-a well-established surrogate of O2-led to a mixture of high-spin and low-spin {FeNO}7 species at low temperature (-70 °C), as indicated by electron paramagnetic resonance (EPR) spectroscopy. At room temperature, these Fe/NO adducts convert to a common species with EPR and infrared (IR) features typical of cationic dinitrosyl iron complexes (DNICs). To complement these results, parallel spectroscopic, computational, and O2/NO reactivity studies were carried out using previously reported TDO models that feature an anionic hydrotris(3-phenyl-5-methyl-pyrazolyl)borate (Ph,MeTp-) ligand. Though the O2 reactivities of the Ph2TIP- and Ph,MeTp-based complexes are quite similar, the supporting ligand perturbs the energies of Fe 3d-based molecular orbitals and modulates Fe-S bond covalency, suggesting possible rationales for the presence of neutral 3His coordination in CDO and ADO.
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Affiliation(s)
- Anne A Fischer
- Department of Chemistry, Marquette University , Milwaukee, Wisconsin 53201, United States
| | - Nuru Stracey
- Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Sergey V Lindeman
- Department of Chemistry, Marquette University , Milwaukee, Wisconsin 53201, United States
| | - Thomas C Brunold
- Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Adam T Fiedler
- Department of Chemistry, Marquette University , Milwaukee, Wisconsin 53201, United States
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20
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Esarey SL, Holland JC, Bartlett BM. Determining the Fate of a Non-Heme Iron Oxidation Catalyst Under Illumination, Oxygen, and Acid. Inorg Chem 2016; 55:11040-11049. [DOI: 10.1021/acs.inorgchem.6b01538] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Samuel L. Esarey
- Department
of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Joel C. Holland
- Department
of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Bart M. Bartlett
- Department
of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
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21
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Levin N, Codesido NO, Bill E, Weyhermüller T, Segantin Gaspari AP, da Silva RS, Olabe JA, Slep LD. Structural, Spectroscopic, and Photochemical Investigation of an Octahedral NO-Releasing {RuNO}7 Species. Inorg Chem 2016; 55:7808-10. [DOI: 10.1021/acs.inorgchem.6b00719] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Natalia Levin
- Universidad de Buenos Aires, Facultad de Ciencias Exactas
y Naturales, Departamento de Química Inorgánica, Analítica
y Química Física, and INQUIMAE , CONICET, Ciudad Universitaria, C1428EHA Buenos Aires, Argentina
| | - Nicolás Osa Codesido
- Universidad de Buenos Aires, Facultad de Ciencias Exactas
y Naturales, Departamento de Química Inorgánica, Analítica
y Química Física, and INQUIMAE , CONICET, Ciudad Universitaria, C1428EHA Buenos Aires, Argentina
| | - Eckhard Bill
- Max-Planck Institut für Chemische Energiekonversion, Stiftstraße 34−36, D-45470 Mülheim an der
Ruhr, Germany
| | - Thomas Weyhermüller
- Max-Planck Institut für Chemische Energiekonversion, Stiftstraße 34−36, D-45470 Mülheim an der
Ruhr, Germany
| | - Ana Paula Segantin Gaspari
- Faculdade de Ciências
Farmacêuticas de Ribeirão Preto, Departamento de Física
e Química, Universidade de São Paulo, Avenida do Café
s/n, 14040-903 Ribeirão
Preto, São Paolo, Brazil
| | - Roberto Santana da Silva
- Faculdade de Ciências
Farmacêuticas de Ribeirão Preto, Departamento de Física
e Química, Universidade de São Paulo, Avenida do Café
s/n, 14040-903 Ribeirão
Preto, São Paolo, Brazil
| | - José A. Olabe
- Universidad de Buenos Aires, Facultad de Ciencias Exactas
y Naturales, Departamento de Química Inorgánica, Analítica
y Química Física, and INQUIMAE , CONICET, Ciudad Universitaria, C1428EHA Buenos Aires, Argentina
| | - Leonardo D. Slep
- Universidad de Buenos Aires, Facultad de Ciencias Exactas
y Naturales, Departamento de Química Inorgánica, Analítica
y Química Física, and INQUIMAE , CONICET, Ciudad Universitaria, C1428EHA Buenos Aires, Argentina
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22
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Higgins RF, Fatur SM, Shepard SG, Stevenson SM, Boston DJ, Ferreira EM, Damrauer NH, Rappé AK, Shores MP. Uncovering the Roles of Oxygen in Cr(III) Photoredox Catalysis. J Am Chem Soc 2016; 138:5451-64. [DOI: 10.1021/jacs.6b02723] [Citation(s) in RCA: 110] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Robert F. Higgins
- Department
of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, United States
| | - Steven M. Fatur
- Department
of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, United States
| | - Samuel G. Shepard
- Department
of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, United States
| | - Susan M. Stevenson
- Department
of Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - David J. Boston
- Department
of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, United States
| | - Eric M. Ferreira
- Department
of Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - Niels H. Damrauer
- Department
of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, United States
| | - Anthony K. Rappé
- Department
of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, United States
| | - Matthew P. Shores
- Department
of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, United States
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