1
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Xiong J, Reed C, Lavina B, Hu MY, Zhao J, Alp EE, Agapie T, Guo Y. 57Fe nuclear resonance vibrational spectroscopic studies of tetranuclear iron clusters bearing terminal iron(iii)-oxido/hydroxido moieties. Chem Sci 2024:d4sc03396e. [PMID: 39296996 PMCID: PMC11403573 DOI: 10.1039/d4sc03396e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2024] [Accepted: 09/08/2024] [Indexed: 09/21/2024] Open
Abstract
57Fe nuclear resonance vibrational spectroscopy (NRVS) has been applied to study a series of tetranuclear iron ([Fe4]) clusters based on a multidentate ligand platform (L3-) anchored by a 1,3,5-triarylbenzene linker and pyrazolate or (tertbutylamino)pyrazolate ligand (PzNH t Bu-). These clusters bear a terminal Fe(iii)-O/OH moiety at the apical position and three additional iron centers forming the basal positions. The three basal irons are connected with the apical iron center via a μ4-oxido ligand. Detailed vibrational analysis via density functional theory calculations revealed that strong NRVS spectral features below 400 cm-1 can be used as an oxidation state marker for the overall [Fe4] cluster core. The terminal Fe(iii)-O/OH stretching frequencies, which were observed in the range of 500-700 cm-1, can be strongly modulated (energy shifts of 20-40 cm-1 were observed) upon redox events at the three remote basal iron centers of the [Fe4] cluster without the change of the terminal Fe(iii) oxidation state and its coordination environment. Therefore, the current study provides a quantitative vibrational analysis of how the remote iron centers within the same iron cluster exert exquisite control of the chemical reactivities and thermodynamic properties of the specific iron site that is responsible for small molecule activation.
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Affiliation(s)
- Jin Xiong
- Department of Chemistry, Carnegie Mellon University Pittsburgh PA 15213 USA
| | - Christopher Reed
- Division of Chemistry and Chemical Engineering, California Institute of Technology CA 91125 USA
| | - Barbara Lavina
- Advanced Photon Source, Argonne National Laboratory Argonne Illinois 60439 USA
- Center for Advanced Radiation Source, University of Chicago Chicago Illinois 60439 USA
| | - Michael Y Hu
- Advanced Photon Source, Argonne National Laboratory Argonne Illinois 60439 USA
| | - Jiyong Zhao
- Advanced Photon Source, Argonne National Laboratory Argonne Illinois 60439 USA
| | - Esen E Alp
- Advanced Photon Source, Argonne National Laboratory Argonne Illinois 60439 USA
| | - Theodor Agapie
- Division of Chemistry and Chemical Engineering, California Institute of Technology CA 91125 USA
| | - Yisong Guo
- Department of Chemistry, Carnegie Mellon University Pittsburgh PA 15213 USA
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2
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Al-Harbi SA. Synthesis and characterization of nano crystallite carboxamide-based iron(III) complexes: SOD mimetic activity, antibacterial and anticancer activity and molecular docking study. J Biomol Struct Dyn 2024; 42:7986-8008. [PMID: 37552248 DOI: 10.1080/07391102.2023.2243341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 07/24/2023] [Indexed: 08/09/2023]
Abstract
Three carboxamide-based ligands and their iron(III) complexes were prepared and structurally characterized. Analytical, thermal and mass spectra measurements showed a 1:1 stoichiometric (M:L) of the synthesized iron(III) complexes. The distorted octahedral geometry of the present iron(III) complexes was assigned based on the results of spectroscopy and magnetometry. Processing of X-ray diffraction data for powder samples by the software Expo 2014 confirmed the octahedral geometry of the three iron(III) complexes. Electrochemical properties of the present iron(III) complexes were studied by cyclic voltammetric measurements. The present iron(III) complexes exhibit SOD like activity with IC50 values of 16.45, 15.24 and 9.70 μM. The drive forces (-λ or ΔG°) controlling these biocatalytic reactions were determined and correlated with catalytic activity. The proposed catalytic mechanistic implications for the conversion of O2•- to H2O2 and H2O were discussed. The antimicrobial activity has been studied in vitro against G(+) and G(-) pathogenic bacteria. The in vitro anticancer activity of the carboxamide-based ligands and their iron(III) complexes against human Hepatocellular carcinoma (HepG-2) cell lines was examined. The obtained results demonstrated the potent anticancer activity of iron(III) complexes with increased safety on normal cells compared to cisplatin. Molecular docking calculations confirmed the experimental findings of the antibacterial and anticancer activities of both free ligands and their iron(III) chelates.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Sami A Al-Harbi
- Chemistry Department, University College in Al-Jamoum, Umm Al-Qura University, Makkah, Saudi Arabia
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3
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Schneider JE, Zeng S, Anferov SW, Filatov AS, Anderson JS. Isolation and Crystallographic Characterization of an Octavalent Co 2O 2 Diamond Core. J Am Chem Soc 2024; 146:23998-24008. [PMID: 39146525 DOI: 10.1021/jacs.4c07335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/17/2024]
Abstract
High-valent cobalt oxides play a pivotal role in alternative energy technology as catalysts for water splitting and as cathodes in lithium-ion batteries. Despite this importance, the properties governing the stability of high-valent cobalt oxides and specifically possible oxygen evolution pathways are not clear. One root of this limited understanding is the scarcity of high-valent Co(IV)-containing model complexes; there are no reports of stable, well-defined complexes with multiple Co(IV) centers. Here, an oxidatively robust fluorinated ligand scaffold enables the isolation and crystallographic characterization of a Co(IV)2-bis-μ-oxo complex. This complex is remarkably stable, in stark contrast with previously reported Co(IV)2 species that are highly reactive, which demonstrates that oxy-Co(IV)2 species are not necessarily unstable with respect to oxygen evolution. This example underscores a new design strategy for highly oxidizing transition-metal fragments and provides detailed data on a previously inaccessible chemical unit of relevance to O-O bond formation and oxygen evolution.
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Affiliation(s)
- Joseph E Schneider
- Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, United States
| | - Shilin Zeng
- Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, United States
| | - Sophie W Anferov
- Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, United States
| | - Alexander S Filatov
- Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, United States
| | - John S Anderson
- Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, United States
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4
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Feng M, Xu Z, Xie H, Lin K, Zhang M. Ultra-efficient peroxymonosulfate utilization and trichloroethylene degradation in heterogeneous catalytic system guided by sheet-like Cu 2MnO 4 nanoparticles: The role of Cu(III)-O species and free radicals. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 366:121799. [PMID: 38991347 DOI: 10.1016/j.jenvman.2024.121799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Revised: 06/13/2024] [Accepted: 07/07/2024] [Indexed: 07/13/2024]
Abstract
Synthesizing cubic spinel Cu2MnO4 with nanosheet structure (SCMO) aimed to construct a "non-radical-mediated radical-oxidative reaction", for increasing PMS utilization efficiency, and solving the defects of SO4•- and •OH through indirect PMS activation by electron transfer process. Compared with box-like Cu2MnO4 (11.1%, 0.0035 min-1) and ordinary Cu2MnO4 nanoparticles (21.3%, 0.0070 min-1), SCMO/PMS showed excellent trichloroethylene removal (98.8%, 0.1577 min-1). The pivotal role of Cu(III) was determined based on EPR analysis, quenching experiments, chemical probe experiments, hydrogen temperature-programmed reduction and Raman spectroscopy analysis, in-situ FTIR and Raman analyses. In brief, the interaction between PMS and SCMO could produce surface-bonded reactive complexes and the subsequent breaking of O-O bond in the sub-stable structure allowed the conversion of Cu(II) to Cu(III), which in turn facilitates the generation of •OH and SO4•-. The density functional theory (DFT) calculations provided supporting evidence for the electron donor role of SCMO and the increase of the electron acceptance capacity of PMS. SCMO/PMS system showed good resistance and degradation efficiency to complex composition and combined pollutants in actually contaminated groundwater, respectively. However, the coexistence of high concentrations of arsenic could significantly affect SCMO performance due to their adsorption on -OH groups, which still need in-depth study.
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Affiliation(s)
- Meiyun Feng
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Zhiqiang Xu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Haijiao Xie
- Hangzhou Yanqu Information Technology Co., Ltd., Hangzhou, 310003, China
| | - Kuangfei Lin
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Meng Zhang
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China; Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China.
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5
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Geoghegan BL, Bilyj JK, Bernhardt PV, DeBeer S, Cutsail GE. X-ray absorption and emission spectroscopy of N 2S 2 Cu(II)/(III) complexes. Dalton Trans 2024; 53:7828-7838. [PMID: 38624161 DOI: 10.1039/d4dt00085d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Abstract
This study investigates the influence of ligand charge on transition energies in a series of CuN2S2 complexes based on dithiocarbazate Schiff base ligands using Cu K-edge X-ray absorption spectroscopy (XAS) and Kβ valence-to-core (VtC) X-ray emission spectroscopy (XES). By comparing the formally Cu(II) complexes [CuII(HL1)] (HL12- = dimethyl pentane-2,4-diylidenebis[carbonodithiohydrazonate]) and [CuII(HL2)] (HL22- = dibenzyl pentane-2,4-diylidenebis[carbonodithiohydrazonate]) and the formally Cu(III) complex [CuIII(L2)], distinct changes in transition energies are observed, primarily attributed to the metal oxidation state. Density functional theory (DFT) calculations demonstrate how an increased negative charge on the deprotonated L23- ligand stabilizes the Cu(III) center through enhanced charge donation, modulating the core transition energies. Overall, significant shifts to higher energies are noted upon metal oxidation, emphasizing the importance of scrutinizing ligand structure in XAS/VtC XES analysis. The data further support the redox-innocent role of the Schiff base ligands and underscore the criticality of ligand protonation levels in future spectroscopic studies, particularly for catalytic intermediates. The combined XAS-VtC XES methodology validates the Cu(III) oxidation state assignment while offering insights into ligand protonation effects on core-level spectroscopic transitions.
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Affiliation(s)
- Blaise L Geoghegan
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany.
- Institute of Inorganic Chemistry, University of Duisburg-Essen, Universitätsstrasse 5-7, 45117 Essen, Germany
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, W12 0BZ, London, UK
| | - Jessica K Bilyj
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane 4072, Australia
| | - Paul V Bernhardt
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane 4072, Australia
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany.
| | - George E Cutsail
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany.
- Institute of Inorganic Chemistry, University of Duisburg-Essen, Universitätsstrasse 5-7, 45117 Essen, Germany
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6
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Wang Y, Xu M, Wang X, Ge R, Zhu YQ, Li AZ, Zhou H, Chen F, Zheng L, Duan H. Unraveling the potential-dependent structure evolution in CuO for electrocatalytic biomass valorization. Sci Bull (Beijing) 2023; 68:2982-2992. [PMID: 37798176 DOI: 10.1016/j.scib.2023.09.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Revised: 08/09/2023] [Accepted: 09/15/2023] [Indexed: 10/07/2023]
Abstract
Electrocatalytic oxidation of renewable biomass (such as glucose) into high-value-added chemicals provides an effective approach to achieving carbon neutrality. CuO-derived materials are among the most promising electrocatalysts for biomass electrooxidation, but the identification of their active sites under electrochemical conditions remains elusive. Herein, we report a potential-dependent structure evolution over CuO in the glucose oxidation reaction (GOR). Through systematic electrochemical and spectroscopic characterizations, we unveil that CuO undergoes Cu2+/Cu+ and Cu3+/Cu2+ redox processes at increased potentials with successive generation of Cu(OH)2 and CuOOH as the active phases. In addition, these two structures have distinct activities in the GOR, with Cu(OH)2 being favorable for aldehyde oxidation, and CuOOH showed faster kinetics in carbon-carbon cleavage and alcohol/aldehyde oxidation. This work deepens our understanding of the dynamic reconstruction of Cu-based catalysts under electrochemical conditions and may guide rational material design for biomass valorization.
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Affiliation(s)
- Ye Wang
- Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Ming Xu
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Xi Wang
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Ruixiang Ge
- Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Yu-Quan Zhu
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - An-Zhen Li
- Department of Chemistry, Tsinghua University, Beijing 100084, China; Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Hua Zhou
- Department of Chemistry, Tsinghua University, Beijing 100084, China; State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Fengen Chen
- Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Lirong Zheng
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Haohong Duan
- Department of Chemistry, Tsinghua University, Beijing 100084, China; Engineering Research Center of Advanced Rare Earth Materials (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, China.
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7
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Cao E, Sun M. Spectral Physics of Stable Cu(III) Produced by Oxidative Addition of an Alkyl Halide. Int J Mol Sci 2023; 24:15694. [PMID: 37958679 PMCID: PMC10648560 DOI: 10.3390/ijms242115694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 10/23/2023] [Accepted: 10/26/2023] [Indexed: 11/15/2023] Open
Abstract
In this paper, we theoretically investigated spectral physics on Cu(III) complexes formed by the oxidative addition of α-haloacetonitrile to ionic and neutral Cu(I) complexes, stimulated by recent experimental reports. Firstly, the electronic structures of reactants of α-haloacetonitrile and neutral Cu(I) and two kinds of products of Cu(III) complexes are visualized with the density of state (DOS) and orbital energy levels of HOMO and LUMO. The visually manifested static and dynamic polarizability as well as the first hyperpolarizability are employed to reveal the vibrational modes of the normal and resonance Raman spectra of two Cu(III) complexes. The nuclear magnetic resonance (NMR) spectra are not only used to identify the reactants and products but also to distinguish between two Cu(III) complexes. The charge difference density (CDD) reveals intramolecular charge transfer in electronic transitions in optical absorption spectra. The CDDs in fluorescence visually reveal electron-hole recombination. Our results promote a deeper understanding of the physical mechanism of stable Cu(III) produced by the oxidative addition of an alkyl halide.
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Affiliation(s)
- En Cao
- School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China;
- Research Institute for Electronic Science, Hokkaido University, Sapporo 001-0021, Japan
| | - Mengtao Sun
- School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China;
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8
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Valdez-Moreira JA, Wannipurage DC, Pink M, Carta V, Moënne-Loccoz P, Telser J, Smith JM. Hydrogen atom abstraction by a high spin [Fe III=S] complex. Chem 2023; 9:2601-2609. [PMID: 39021493 PMCID: PMC11251717 DOI: 10.1016/j.chempr.2023.05.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
Iron sulfur clusters are critical to a plethora of biological processes; however, little is known about the elementary unit of these clusters, namely the [Fe=S]n+ fragment. Here, we report the synthesis and characterization of a terminal iron sulfido complex. Despite its high spin (S = 5/2) ground state, structural, spectroscopic, and computational characterization provide evidence for iron sulfur multiple bond character. Intriguingly, the complex reacts with additional sulfur to afford an S = 3/2 iron(III) disulfido (S2 2-) complex. Preliminary studies reveal that the sulfido complex reacts with dihydroanthracene to afford an iron(II) hydrosulfido complex, akin to the reactivity of iron oxo complexes. By contrast, there is no reaction with the disulfido complex. These results provide important insight into the nature of the iron sulfide unit.
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Affiliation(s)
| | | | - Maren Pink
- Department of Chemistry, Indiana University, Bloomington, IN 47405, USA
| | - Veronica Carta
- Department of Chemistry, Indiana University, Bloomington, IN 47405, USA
| | - Pierre Moënne-Loccoz
- Department of Chemical Physiology and Biochemistry, School of Medicine, Oregon Health & Science University, Portland, OR 97239, USA
| | - Joshua Telser
- Department of Biological, Physical and Health Sciences, Roosevelt University, Chicago, IL 60605, USA
| | - Jeremy M. Smith
- Department of Chemistry, Indiana University, Bloomington, IN 47405, USA
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9
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Hall K, Joseph C, Ayuso-Fernández I, Tamhankar A, Rieder L, Skaali R, Golten O, Neese F, Røhr ÅK, Jannuzzi SAV, DeBeer S, Eijsink VGH, Sørlie M. A Conserved Second Sphere Residue Tunes Copper Site Reactivity in Lytic Polysaccharide Monooxygenases. J Am Chem Soc 2023; 145:18888-18903. [PMID: 37584157 PMCID: PMC10472438 DOI: 10.1021/jacs.3c05342] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Indexed: 08/17/2023]
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are powerful monocopper enzymes that can activate strong C-H bonds through a mechanism that remains largely unknown. Herein, we investigated the role of a conserved glutamine/glutamate in the second coordination sphere. Mutation of the Gln in NcAA9C to Glu, Asp, or Asn showed that the nature and distance of the headgroup to the copper fine-tune LPMO functionality and copper reactivity. The presence of Glu or Asp close to the copper lowered the reduction potential and decreased the ratio between the reduction and reoxidation rates by up to 500-fold. All mutants showed increased enzyme inactivation, likely due to changes in the confinement of radical intermediates, and displayed changes in a protective hole-hopping pathway. Electron paramagnetic resonance (EPR) and X-ray absorption spectroscopic (XAS) studies gave virtually identical results for all NcAA9C variants, showing that the mutations do not directly perturb the Cu(II) ligand field. DFT calculations indicated that the higher experimental reoxidation rate observed for the Glu mutant could be reconciled if this residue is protonated. Further, for the glutamic acid form, we identified a Cu(III)-hydroxide species formed in a single step on the H2O2 splitting path. This is in contrast to the Cu(II)-hydroxide and hydroxyl intermediates, which are predicted for the WT and the unprotonated glutamate variant. These results show that this second sphere residue is a crucial determinant of the catalytic functioning of the copper-binding histidine brace and provide insights that may help in understanding LPMOs and LPMO-inspired synthetic catalysts.
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Affiliation(s)
- Kelsi
R. Hall
- Faculty
of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432, Ås, Norway
| | - Chris Joseph
- Max
Planck Institute for Chemical Energy Conversion, Stiftstraße 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Iván Ayuso-Fernández
- Faculty
of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432, Ås, Norway
| | - Ashish Tamhankar
- Max
Planck Institute for Chemical Energy Conversion, Stiftstraße 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Lukas Rieder
- Institute
for Molecular Biotechnology, Graz University
of Technology, 8010, Graz, Austria
| | - Rannei Skaali
- Faculty
of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432, Ås, Norway
| | - Ole Golten
- Faculty
of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432, Ås, Norway
| | - Frank Neese
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Åsmund K. Røhr
- Faculty
of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432, Ås, Norway
| | - Sergio A. V. Jannuzzi
- Max
Planck Institute for Chemical Energy Conversion, Stiftstraße 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Serena DeBeer
- Max
Planck Institute for Chemical Energy Conversion, Stiftstraße 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Vincent G. H. Eijsink
- Faculty
of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432, Ås, Norway
| | - Morten Sørlie
- Faculty
of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432, Ås, Norway
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10
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Bhowmick R, Roy Chowdhury S, Vlaisavljevich B. Molecular Geometry and Electronic Structure of Copper Corroles. Inorg Chem 2023; 62:13877-13891. [PMID: 37590888 DOI: 10.1021/acs.inorgchem.3c01779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/19/2023]
Abstract
Copper corroles are known for their unique multiconfigurational electronic structures in the ground state, which arise from the transfer of electrons from the π orbitals of the corrole to the d-orbital of copper. While density functional theory (DFT) provides reasonably good molecular geometries, the determination of the ground spin state and the associated energetics is heavily influenced by functional choice, particularly the percentage of the Hartree-Fock exchange. Using extended multireference perturbation theory methods (XMS-CASPT2), the functional choice can be assessed. The molecular geometries and electronic structures of both the unsubstituted and the meso-triphenyl copper corroles were investigated. A minimal active space was employed for structural characterization, while larger active spaces are required to examine the electronic structure. The XMS-CASPT2 investigations conclusively identify the ground electronic state as a multiconfigurational singlet (S0) with three dominant electronic configurations in its lowest energy and characteristic saddled structure. In contrast, the planar geometry corresponds to the triplet state (T0), which is approximately 5 kcal/mol higher in energy compared to the S0 state for both the bare and substituted copper corroles. Notably, the planarity of the T0 geometry is reduced in the substituted corrole compared with that in the unsubstituted one. By analyzing the potential energy surface (PES) between the S0 and T0 geometries using XMS-CASPT2, the multiconfigurational electronic structure is shown to transition toward a single electron configuration as the saddling angle decreases (i.e., as one approaches the planar geometry). Despite the ability of the functionals to reproduce the minimum energy structures, only the TPSSh-D3 PES is reasonably close to the XMS-CASPT2 surface. Significant deviations along the PES are observed with other functionals.
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Affiliation(s)
- Rina Bhowmick
- Department of Chemistry, University of South Dakota, Vermillion, South Dakota 57069, United States
| | - Sabyasachi Roy Chowdhury
- Department of Chemistry, University of South Dakota, Vermillion, South Dakota 57069, United States
| | - Bess Vlaisavljevich
- Department of Chemistry, University of South Dakota, Vermillion, South Dakota 57069, United States
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11
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Mechanistic Insights for Dual-Species Evolution toward 5-Hydroxymethylfurfural Oxidation. J Catal 2022. [DOI: 10.1016/j.jcat.2022.11.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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12
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Wang QY, Sun ZB, Zhang M, Zhao SN, Luo P, Gong CH, Liu WX, Zang SQ. Cooperative Catalysis between Dual Copper Centers in a Metal–Organic Framework for Efficient Detoxification of Chemical Warfare Agent Simulants. J Am Chem Soc 2022; 144:21046-21055. [DOI: 10.1021/jacs.2c05176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Qian-You Wang
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
| | - Zhi-Bing Sun
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
| | - Meng Zhang
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
| | - Shu-Na Zhao
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
| | - Peng Luo
- College of Chemistry and Chemical Engineering, Henan Polytechnic University, Jiaozuo 454000, China
| | - Chun-Hua Gong
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
| | - Wen-Xiao Liu
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
| | - Shuang-Quan Zang
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
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13
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Heyer AJ, Plessers D, Braun A, Rhoda HM, Bols ML, Hedman B, Hodgson KO, Schoonheydt RA, Sels BF, Solomon EI. Methane Activation by a Mononuclear Copper Active Site in the Zeolite Mordenite: Effect of Metal Nuclearity on Reactivity. J Am Chem Soc 2022; 144:19305-19316. [PMID: 36219763 DOI: 10.1021/jacs.2c06269] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The direct conversion of methane to methanol would have a wide reaching environmental and industrial impact. Copper-containing zeolites can perform this reaction at low temperatures and pressures at a previously defined O2-activated [Cu2O]2+ site. However, after autoreduction of the copper-containing zeolite mordenite and removal of the [Cu2O]2+ active site, the zeolite is still methane reactive. In this study, we use diffuse reflectance UV-vis spectroscopy, magnetic circular dichroism, resonance Raman spectroscopy, electron paramagnetic resonance, and X-ray absorption spectroscopy to unambiguously define a mononuclear [CuOH]+ as the CH4 reactive active site of the autoreduced zeolite. The rigorous identification of a mononuclear active site allows a reactivity comparison to the previously defined [Cu2O]2+ active site. We perform kinetic experiments to compare the reactivity of the [CuOH]+ and [Cu2O]2+ sites and find that the binuclear site is significantly more reactive. From the analysis of density functional theory calculations, we elucidate that this increased reactivity is a direct result of stabilization of the [Cu2OH]2+ H-atom abstraction product by electron delocalization over the two Cu cations via the bridging ligand. This significant increase in reactivity from electron delocalization over a binuclear active site provides new insights for the design of highly reactive oxidative catalysts.
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Affiliation(s)
- Alexander J Heyer
- Department of Chemistry, Stanford University, Stanford, California94305, United States
| | - Dieter Plessers
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, LeuvenB-3001, Belgium
| | - Augustin Braun
- Department of Chemistry, Stanford University, Stanford, California94305, United States
| | - Hannah M Rhoda
- Department of Chemistry, Stanford University, Stanford, California94305, United States
| | - Max L Bols
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, LeuvenB-3001, Belgium
| | - Britt Hedman
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California94025, United States
| | - Keith O Hodgson
- Department of Chemistry, Stanford University, Stanford, California94305, United States.,Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California94025, United States
| | - Robert A Schoonheydt
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, LeuvenB-3001, Belgium
| | - Bert F Sels
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, LeuvenB-3001, Belgium
| | - Edward I Solomon
- Department of Chemistry, Stanford University, Stanford, California94305, United States.,Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California94025, United States
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14
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Albert T, Moënne-Loccoz P. Spectroscopic Characterization of a Diferric Mycobacterial Hemerythrin-Like Protein with Unprecedented Reactivity toward Nitric Oxide. J Am Chem Soc 2022; 144:17611-17621. [PMID: 36099449 DOI: 10.1021/jacs.2c07113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hemerythrin-like proteins (HLPs) are broadly distributed across taxonomic groups and appear to play highly diverse functional roles in prokaryotes. Mycobacterial HLPs contribute to the survival of these pathogenic bacteria in mammalian macrophages, but their modes of action remain unclear. A recent crystallographic characterization of Mycobacterium kansasii HLP (Mka-HLP) revealed the unexpected presence of a tyrosine sidechain (Tyr54) near the coordination sphere of one of the two iron centers. Here, we show that Tyr54 is a true ligand to the Fe2(III) ion which, in conjunction with the presence of a μ-oxo group bridging the two iron(III), brings unique reactivity toward nitric oxide (NO). Monitoring the titration of Mka-HLP with NO by Fourier-transform infrared and electron paramagnetic resonance spectroscopies shows that both diferric and diferrous forms of Mka-HLP accumulate an uncoupled high-spin and low-spin {FeNO}7 pair. We assign the reactivity of the diferric protein to an initial radical reaction between NO and the μ-oxo bridge to form nitrite and a mixed-valent diiron center that can react further with NO. Amperometric measurements of NO consumption by Mka-HLP confirm that this reactivity can proceed at low micromolar concentrations of NO, before additional NO consumption, supporting a NO scavenging role for mycobacterial HLPs.
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Affiliation(s)
- Therese Albert
- Department of Chemical Physiology and Biochemistry, School of Medicine, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, United States
| | - Pierre Moënne-Loccoz
- Department of Chemical Physiology and Biochemistry, School of Medicine, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, United States
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15
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McKee ML. Exploring the Reaction Mechanism of C-H Oxidation by Copper-Salen Complexes. J Phys Chem A 2022; 126:4969-4980. [PMID: 35861503 DOI: 10.1021/acs.jpca.2c03344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The mechanism of C-H oxidation of propylene (C3H6) and 1-phenyl-1-pentyne (C3H7-C≡C-Ph) by HOOR (R═Me, tBu) and 3O2 by a copper-salen complex was explored by computations. The most noteworthy step is the complexation of two Cu salens to the peroxide to form either the LCuOH/LCuOR pair or an OH-bridged complex LCu(μ-OH)CuL plus OR. The latter pathway involves an avoided crossing of two triplet electronic states. The LCuOH complex can abstract a hydrogen atom from C3H6 and the C3H5 radical plus 3O2 forms the complex LCuOOC3H5. Migration of a hydrogen to the proximal oxygen atom reforms LCuOH and acrolein HC(O)CH═CH2.
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Affiliation(s)
- Michael L McKee
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama36849, United States
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16
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Wei Y, Miao J, Ge J, Lang J, Yu C, Zhang L, Alvarez PJJ, Long M. Ultrahigh Peroxymonosulfate Utilization Efficiency over CuO Nanosheets via Heterogeneous Cu(III) Formation and Preferential Electron Transfer during Degradation of Phenols. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:8984-8992. [PMID: 35638588 DOI: 10.1021/acs.est.2c01968] [Citation(s) in RCA: 44] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In persulfate activation by copper-based catalysts, high-valent copper (Cu(III)) is an overlooked reactive intermediate that contributes to efficient persulfate utilization and organic pollutant removal. However, the mechanisms underlying heterogeneous activation and enhanced persulfate utilization are not fully understood. Here, copper oxide (CuO) nanosheets (synthesized with a facile precipitation method) exhibited high catalytic activity for peroxymonosulfate (PMS) activation with 100% 4-chlorophenol (4-CP) degradation within 3 min. Evidence for the critical role of surface-associated Cu(III) on PMS activation and 4-CP degradation over a wide pH range (pH 3-10) was obtained using in situ Raman spectroscopy, electron paramagnetic resonance, and quenching tests. Cu(III) directly oxidized 4-CP and other phenolic pollutants, with rate constants inversely proportional to their ionization potentials. Cu(III) preferentially oxidizes 4-CP rather than react with two PMS molecules to generate one molecule of 1O2, thus minimizing this less efficient PMS utilization pathway. Accordingly, a much higher PMS utilization efficiency (77% of electrons accepted by PMS ascribed to 4-CP mineralization) was obtained with CuO/PMS than with a radical pathway-dominated Co3O4/PMS system (27%) or with the 1O2 pathway-dominated α-MnO2/PMS system (26%). Overall, these results highlight the potential benefits of PMS activation via heterogeneous high-valent copper oxidation and offer mechanistic insight into ultrahigh PMS utilization efficiency for organic pollutant removal.
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Affiliation(s)
- Yan Wei
- School of Environmental Science and Engineering, Key Laboratory for Thin Film and Microfabrication of the Ministry of Education, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Jie Miao
- School of Environmental Science and Engineering, Key Laboratory for Thin Film and Microfabrication of the Ministry of Education, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Jianxin Ge
- School of Environmental Science and Engineering, Key Laboratory for Thin Film and Microfabrication of the Ministry of Education, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Junyu Lang
- School of Physical Science and Technology, Shanghai Tech University, Shanghai 201210, China
| | - Chunyang Yu
- School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Lizhi Zhang
- School of Environmental Science and Engineering, Key Laboratory for Thin Film and Microfabrication of the Ministry of Education, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Pedro J J Alvarez
- Department of Civil and Environmental Engineering, Rice University, Houston, Texas 77005, United States
| | - Mingce Long
- School of Environmental Science and Engineering, Key Laboratory for Thin Film and Microfabrication of the Ministry of Education, Shanghai Jiao Tong University, Shanghai 200240, China
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17
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Pang X, Zhao H, Huang Y, Liu Y, Bai H, Fan W, Shi W. In Situ Electrochemical Reconstitution of CF-CuO/CeO 2 for Efficient Active Species Generation. Inorg Chem 2022; 61:8940-8954. [PMID: 35653625 DOI: 10.1021/acs.inorgchem.2c01338] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Achievement of the intrinsic activity by in situ electrochemical reconstruction has been becoming a great challenge for designing a catalyst. Herein, an effective electrochemical strategy is proposed to reconstruct the surface of the CF-CuO/CeO2 precursor. Under the stimulation of oxidative/reductive potential, abundant active sites were successfully generated on the surface of CF-CuO/CeO2. Remarkably, the implantation of oxygen vacancy-rich CeO2 synergistically optimizes the chemical composition and electronic structure of CF-CuO/CeO2, greatly promoting the generation of active species. Systematic electrochemical experiments indicate that the superior catalytic performance of reconstructed CF-CuO/CeO2 could be attributed to CuOOH/CeO2 and Cu2O/Ce2O3 active species, respectively. The oxidative-/reductive-activated CF-CuO/CeO2 was further employed in a paired cell for the synergistic catalysis of hydroxymethylfurfural oxidation with 4-nitrophenol hydrogenation. As a result, nearly 100% Faraday efficiency for furandicarboxylic acid/4-aminophenol production was achieved in the paired system (-0.9 V vs Ag/AgCl, 1.5 h). Therefore, the electrochemical reconstruction via oxidative/reductive activation has been confirmed as a feasible approach to significantly excite the intrinsic activity of a catalyst.
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Affiliation(s)
- Xuliang Pang
- School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, P. R. China
| | - Huaiquan Zhao
- School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, P. R. China
| | - Yifei Huang
- School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, P. R. China
| | - Youchao Liu
- School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, P. R. China
| | - Hongye Bai
- School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, P. R. China
| | - Weiqiang Fan
- School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, P. R. China
| | - Weidong Shi
- School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, P. R. China
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18
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Theoretical perspective on mononuclear copper-oxygen mediated C–H and O–H activations: A comparison between biological and synthetic systems. CHINESE JOURNAL OF CATALYSIS 2022. [DOI: 10.1016/s1872-2067(21)63974-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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19
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Pang X, Bai H, Zhao H, Fan W, Shi W. Efficient Electrocatalytic Oxidation of 5-Hydroxymethylfurfural Coupled with 4-Nitrophenol Hydrogenation in a Water System. ACS Catal 2022. [DOI: 10.1021/acscatal.1c04880] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Xuliang Pang
- School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, P. R. China
| | - Hongye Bai
- School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, P. R. China
| | - Huaiquan Zhao
- School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, P. R. China
| | - Weiqiang Fan
- School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, P. R. China
| | - Weidong Shi
- School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, P. R. China
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20
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Lan Z, Toney J, Mallikarjun Sharada S. A computational mechanistic study of CH hydroxylation with mononuclear copper–oxygen complexes. Catal Sci Technol 2022. [DOI: 10.1039/d2cy01128j] [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
A computational study of methane hydroxylation by oxygen-bound monocopper complexes.
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Affiliation(s)
- Zhenzhuo Lan
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA, USA
| | - Jacob Toney
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA, USA
| | - Shaama Mallikarjun Sharada
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA, USA
- Department of Chemistry, University of Southern California, Los Angeles, CA, USA
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21
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Goetz MK, Schneider JE, Filatov AS, Jesse KA, Anderson JS. Enzyme-Like Hydroxylation of Aliphatic C-H Bonds From an Isolable Co-Oxo Complex. J Am Chem Soc 2021; 143:20849-20862. [PMID: 34856101 DOI: 10.1021/jacs.1c09280] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The selective hydroxylation of aliphatic C-H bonds remains a challenging but broadly useful transformation. Nature has evolved systems that excel at this reaction, exemplified by cytochrome P450 enzymes, which use an iron-oxo intermediate to activate aliphatic C-H bonds with k1 > 1400 s-1 at 4 °C. Many synthetic catalysts have been inspired by these enzymes and are similarly proposed to use transition metal-oxo intermediates. However, most examples of well-characterized transition metal-oxo species are not capable of reacting with strong, aliphatic C-H bonds, resulting in a lack of understanding of what factors facilitate this reactivity. Here, we report the isolation and characterization of a new terminal CoIII-oxo complex, PhB(AdIm)3CoIIIO. Upon oxidation, a transient CoIV-oxo intermediate is generated that is capable of hydroxylating aliphatic C-H bonds with an extrapolated k1 for C-H activation >130 s-1 at 4 °C, comparable to values observed in cytochrome P450 enzymes. Experimental thermodynamic values and DFT analysis demonstrate that, although the initial C-H activation step in this reaction is endergonic, the overall reaction is driven by an extremely exergonic radical rebound step, similar to what has been proposed in cytochrome P450 enzymes. The rapid C-H hydroxylation reactivity displayed in this well-defined system provides insight into how hydroxylation is accomplished by biological systems and similarly potent synthetic oxidants.
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Affiliation(s)
- McKenna K Goetz
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Joseph E Schneider
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Alexander S Filatov
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Kate A Jesse
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - John S Anderson
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
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22
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Fujisawa K, Sakuma S, Ikarugi R, Jose A, Solomon EI. Thermally stable manganese(III) peroxido complexes with hindered N3 tripodal ligands: Structures and their physicochemical properties. J Inorg Biochem 2021; 225:111597. [PMID: 34547605 PMCID: PMC10019377 DOI: 10.1016/j.jinorgbio.2021.111597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 08/25/2021] [Accepted: 08/28/2021] [Indexed: 11/20/2022]
Abstract
Mononuclear manganese(III) peroxido complexes are candidates for the reaction intermediates in manganese containing proteins, such as manganese superoxide dismutase (Mn-SOD) etc. In this study, manganese(III) peroxido complexes [Mn(O2)(L3)] and [Mn(O2)(L10)] ligated by anionic N3 type ligands with sterically hindered substituents, hydrotris(3-tertiary butyl-5-isopropyl-1-pyrazolyl)borate (L3-) and hydrotris(3-adamantyl-5-isopropyl-1-pyrazolyl)borate (L10-), respectively, were structurally characterized. These complexes are the first examples of structurally characterized five-coordinate manganese(III) peroxido complexes. Their characteristic ν(OO) and ν(MnO) stretchings were determined by using H218O2 for the first time. Theoretical calculations were performed to obtain further insight into their structural parameters. The decomposed products were obtained as [{MnIII(μ-O)(L3)}2MnIV] and [MnIII(OH){L10(O)}] from [Mn(O2)(L3)] and [Mn(O2)(L10)], respectively.
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Affiliation(s)
- Kiyoshi Fujisawa
- Department of Chemistry, Ibaraki University, Mito 310-8512, Japan.
| | - Syuhei Sakuma
- Department of Chemistry, Ibaraki University, Mito 310-8512, Japan
| | - Riko Ikarugi
- Department of Chemistry, Ibaraki University, Mito 310-8512, Japan
| | - Anex Jose
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Edward I Solomon
- Department of Chemistry, Stanford University, Stanford, California 94305, United States; Stanford Synchrotron Radiation Lightsource, SLAC, Stanford University, Menlo Park, California 94025, United States.
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23
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24
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Karmalkar DG, Seo MS, Lee YM, Kim Y, Lee E, Sarangi R, Fukuzumi S, Nam W. Deeper Understanding of Mononuclear Manganese(IV)-Oxo Binding Brønsted and Lewis Acids and the Manganese(IV)-Hydroxide Complex. Inorg Chem 2021; 60:16996-17007. [PMID: 34705465 DOI: 10.1021/acs.inorgchem.1c02119] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Binding of Lewis acidic metal ions and Brønsted acid at the metal-oxo group of high-valent metal-oxo complexes enhances their reactivities significantly in oxidation reactions. However, such a binding of Lewis acids and proton at the metal-oxo group has been questioned in several cases and remains to be clarified. Herein, we report the synthesis, characterization, and reactivity studies of a mononuclear manganese(IV)-oxo complex binding triflic acid, {[(dpaq)MnIV(O)]-HOTf}+ (1-HOTf). First, 1-HOTf was synthesized and characterized using various spectroscopic techniques, including resonance Raman (rRaman) and X-ray absorption spectroscopy/extended X-ray absorption fine structure. In particular, in rRaman experiments, we observed a linear correlation between the Mn-O stretching frequencies of 1-HOTf (e.g., νMn-O at ∼793 cm-1) and 1-Mn+ (Mn+ = Ca2+, Zn2+, Lu3+, Al3+, or Sc3+) and the Lewis acidities of H+ and Mn+ ions, suggesting that H+ and Mn+ bind at the metal-oxo moiety of [(dpaq)MnIV(O)]+. Interestingly, a single-crystal structure of 1-HOTf was obtained by X-ray diffraction analysis, but the structure was not an expected Mn(IV)-oxo complex but a Mn(IV)-hydroxide complex, [(dpaq)MnIV(OH)](OTf)2 (4), with a Mn-O bond distance of 1.8043(19) Å and a Mn-O stretch at 660 cm-1. More interestingly, 4 reverted to 1-HOTf upon dissolution, demonstrating that 1-HOTf and 4 are interconvertible depending on the physical states, such as 1-HOTf in solution and 4 in isolated solid. The reactivity of 1-HOTf was investigated in hydrogen atom transfer (HAT) and oxygen atom transfer (OAT) reactions and then compared with those of 1-Mn+ complexes; an interesting correlation between the Mn-O stretching frequencies of 1-HOTf and 1-Mn+ and their reactivities in the OAT and HAT reactions is reported for the first time in this study.
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Affiliation(s)
- Deepika G Karmalkar
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Mi Sook Seo
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Yong-Min Lee
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Youngsuk Kim
- Department of Chemistry, Pohang University of Science and Technology, Pohang 37673, Korea
| | - Eunsung Lee
- Department of Chemistry, Pohang University of Science and Technology, Pohang 37673, Korea
| | - Ritimukta Sarangi
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, California 94025, United States
| | - Shunichi Fukuzumi
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Wonwoo Nam
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
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25
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Liu H, Shen Q. Well-defined organometallic Copper(III) complexes: Preparation, characterization and reactivity. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2021.213923] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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26
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Wu W, De Hont JT, Parveen R, Vlaisavljevich B, Tolman WB. Sulfur-Containing Analogues of the Reactive [CuOH] 2+ Core. Inorg Chem 2021; 60:5217-5223. [PMID: 33733755 DOI: 10.1021/acs.inorgchem.1c00216] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
With the aim of drawing comparisons to the highly reactive complex LCuOH (L = bis(2,6-diisopropylphenylcarboxamido)pyridine), the complexes [Bu4N][LCuSR] (R = H or Ph) were prepared, characterized by spectroscopy and X-ray crystallography, and oxidized at low temperature to generate the species assigned as LCuSR on the basis of spectroscopy and theory. Consistent with the smaller electronegativity of S versus O, redox potentials for the LCuSR-/0 couples were ∼50 mV lower than for LCuOH-/0, and the rates of the proton-coupled electron transfer reactions of LCuSR with anhydrous 1-hydroxy-2,2,6,6-tetramethyl-piperidine at -80 °C were significantly slower (by more than 100 times) than the same reaction of LCuOH. Density functional theory (DFT) and time-dependent DFT calculations on LCuZ (Z = OH, SH, SPh) revealed subtle differences in structural and UV-visible parameters. Further comparison to complexes with Z = F, Cl, and Br using complete active space (CAS) self-consistent field and localized orbital CAS configuration interaction calculations along with a valence-bond-like interpretation of the wave functions showed differences with previously reported results ( J. Am. Chem. Soc. 2020, 142, 8514), and argue for a consistent electronic structure across the entire series of complexes, rather than a change in the nature of the ligand field arrangement for Z = F.
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Affiliation(s)
- Wen Wu
- Department of Chemistry, Washington University in St. Louis, One Brookings Hall, Campus Box 1134, St. Louis, Missouri 63130-4899, United States
| | - Jacqui Tehranchi De Hont
- Department of Chemistry, University of Minnesota, 207 Pleasant Avenue SE, Minneapolis, Minnesota 55455, United States
| | - Riffat Parveen
- University of South Dakota, 414 E. Clark Street, Vermillion, South Dakota 57069, United States
| | - Bess Vlaisavljevich
- University of South Dakota, 414 E. Clark Street, Vermillion, South Dakota 57069, United States
| | - William B Tolman
- Department of Chemistry, Washington University in St. Louis, One Brookings Hall, Campus Box 1134, St. Louis, Missouri 63130-4899, United States
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27
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Krishnan VM, Shopov DY, Bouchey CJ, Bailey WD, Parveen R, Vlaisavljevich B, Tolman WB. Structural Characterization of the [CuOR] 2+ Core. J Am Chem Soc 2021; 143:3295-3299. [PMID: 33621089 DOI: 10.1021/jacs.0c13470] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Formal Cu(III) complexes bearing an oxygen-based auxiliary ligand ([CuOR]2+, R = H or CH2CF3) were stabilized by modulating the donor character of supporting ligand LY (LY = 4-Y, N,N'-bis(2,6-diisopropylphenyl)-2,6-pyridinedicarboxamide, Y = H or OMe) and/or the basicity of the auxiliary ligand, enabling the first characterization of these typically highly reactive cores by NMR spectroscopy and X-ray crystallography. Enhanced lifetimes in solution and slowed rates of PCET with a phenol substrate were observed. NMR spectra corroborate the S = 0 ground states of the complexes, and X-ray structures reveal shortened Cu-ligand bond distances that match well with theory.
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Affiliation(s)
- V Mahesh Krishnan
- Department of Chemistry, Washington University in St. Louis, One Brookings Hall, Campus Box 1134, St. Louis, Missouri 63130-4899, United States
| | - Dimitar Y Shopov
- Department of Chemistry, Washington University in St. Louis, One Brookings Hall, Campus Box 1134, St. Louis, Missouri 63130-4899, United States
| | - Caitlin J Bouchey
- Department of Chemistry, Washington University in St. Louis, One Brookings Hall, Campus Box 1134, St. Louis, Missouri 63130-4899, United States
| | - Wilson D Bailey
- Department of Chemistry, Washington University in St. Louis, One Brookings Hall, Campus Box 1134, St. Louis, Missouri 63130-4899, United States
| | - Riffat Parveen
- University of South Dakota, 414 E. Clark Street, Vermillion, South Dakota 57069, United States
| | - Bess Vlaisavljevich
- University of South Dakota, 414 E. Clark Street, Vermillion, South Dakota 57069, United States
| | - William B Tolman
- Department of Chemistry, Washington University in St. Louis, One Brookings Hall, Campus Box 1134, St. Louis, Missouri 63130-4899, United States
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28
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Oda A, Tanaka T, Sawabe K, Satsuma A. How to Constrain Metal-Oxyl Bonds on a Solid Surface? Lesson from Isovalent Zn(II)-Oxyl and Ga(III)-Oxyl Bonds Isolated in Zeolite Matrix. J Phys Chem Lett 2020; 11:9426-9431. [PMID: 33107740 DOI: 10.1021/acs.jpclett.0c02980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Isolation of the atomic O radical anion bound to a metal ion (metal-oxyl) on solid surfaces is highly desirable for an understanding of how we should design the surface structure for using oxyl as the reactive site. Owing to the analytical difficulty of oxyl, however, even identification of oxyl remains scarce. Herein, we report isovalent ZnII-oxyl and GaIII-oxyl bonds isolated in the zeolite matrix. Close similarities in reactivity, spectroscopic property, and bonding nature were observed between them, but their site requirements were entirely different; the former is generated at the monovalent ion-exchangeable site, whereas the latter at the divalent ion-exchangeable site. This study strongly suggests that tuning the polarization of the metal-oxygen bond using the charge-controlled lattice oxygens is a useful way to constrain surface metal-oxyl bonds.
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Affiliation(s)
- Akira Oda
- Department of Materials Chemistry, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
- Elements Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University, Kyoto 615-8520, Japan
| | - Tomoyasu Tanaka
- Department of Materials Chemistry, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
| | - Kyoichi Sawabe
- Department of Materials Chemistry, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
| | - Atsushi Satsuma
- Department of Materials Chemistry, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
- Elements Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University, Kyoto 615-8520, Japan
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29
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Elwell CE, Mandal M, Bouchey CJ, Que L, Cramer CJ, Tolman WB. Carboxylate Structural Effects on the Properties and Proton-Coupled Electron Transfer Reactivity of [CuO 2CR] 2+ Cores. Inorg Chem 2019; 58:15872-15879. [PMID: 31710477 DOI: 10.1021/acs.inorgchem.9b02293] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A series of complexes {[NBu4][LCuII(O2CR)] (R = -C6F5, -C6H4(NO2), -C6H5, -C6H4(OMe), -CH3, and -C6H2(iPr)3)} were characterized (with the complex R = -C6H4(m-Cl) having been published elsewhere ( Mandal et al. J. Am. Chem. Soc. 2019 , 141 , 17236 )). All feature N,N',N″-coordination of the supporting L2- ligand, except for the complex with R = -C6H2(iPr)3, which exhibits N,N',O-coordination. For the N,N',N″-bound complexes, redox properties, UV-vis ligand-to-metal charge transfer (LMCT) features, and rates of hydrogen atom abstraction from 2,4,6,-tri-t-butylphenol using the oxidized, formally Cu(III) compounds LCuIII(O2CR) correlated well with the electron donating nature of R as measured both experimentally and computationally. Specifically, the greater the electron donation, the lower is the energy for LMCT and the slower is the reaction rate. The results are interpreted to support an oxidatively asynchronous proton-coupled electron transfer mechanism that is sensitive to the oxidative power of the [CuIII(O2CR)]2+ core.
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Affiliation(s)
- Courtney E Elwell
- Department of Chemistry, Center for Metals in Biocatalysis, Chemical Theory Center, and Supercomputing Institute , University of Minnesota , 207 Pleasant Street SE , Minneapolis , Minnesota 55455 , United States
| | - Mukunda Mandal
- Department of Chemistry, Center for Metals in Biocatalysis, Chemical Theory Center, and Supercomputing Institute , University of Minnesota , 207 Pleasant Street SE , Minneapolis , Minnesota 55455 , United States
| | - Caitlin J Bouchey
- Department of Chemistry, Center for Metals in Biocatalysis, Chemical Theory Center, and Supercomputing Institute , University of Minnesota , 207 Pleasant Street SE , Minneapolis , Minnesota 55455 , United States.,Department of Chemistry , Washington University in St. Louis , One Brookings Drive, Campus Box 1134 , St. Louis , Missouri 63130 , United States
| | - Lawrence Que
- Department of Chemistry, Center for Metals in Biocatalysis, Chemical Theory Center, and Supercomputing Institute , University of Minnesota , 207 Pleasant Street SE , Minneapolis , Minnesota 55455 , United States
| | - Christopher J Cramer
- Department of Chemistry, Center for Metals in Biocatalysis, Chemical Theory Center, and Supercomputing Institute , University of Minnesota , 207 Pleasant Street SE , Minneapolis , Minnesota 55455 , United States
| | - William B Tolman
- Department of Chemistry , Washington University in St. Louis , One Brookings Drive, Campus Box 1134 , St. Louis , Missouri 63130 , United States
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Gordon JB, Vilbert AC, DiMucci IM, MacMillan SN, Lancaster KM, Moënne-Loccoz P, Goldberg DP. Activation of Dioxygen by a Mononuclear Nonheme Iron Complex: Sequential Peroxo, Oxo, and Hydroxo Intermediates. J Am Chem Soc 2019; 141:17533-17547. [PMID: 31647656 DOI: 10.1021/jacs.9b05274] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The activation of dioxygen by FeII(Me3TACN)(S2SiMe2) (1) is reported. Reaction of 1 with O2 at -135 °C in 2-MeTHF generates a thiolate-ligated (peroxo)diiron complex FeIII2(O2)(Me3TACN)2(S2SiMe2)2 (2) that was characterized by UV-vis (λmax = 300, 390, 530, 723 nm), Mössbauer (δ = 0.53, |ΔEQ| = 0.76 mm s-1), resonance Raman (RR) (ν(O-O) = 849 cm-1), and X-ray absorption (XAS) spectroscopies. Complex 2 is distinct from the outer-sphere oxidation product 1ox (UV-vis (λmax = 435, 520, 600 nm), Mössbauer (δ = 0.45, |ΔEQ| = 3.6 mm s-1), and EPR (S = 5/2, g = [6.38, 5.53, 1.99])), obtained by one-electron oxidation of 1. Cleavage of the peroxo O-O bond can be initiated either photochemically or thermally to produce a new species assigned as an FeIV(O) complex, FeIV(O)(Me3TACN)(S2SiMe2) (3), which was identified by UV-vis (λmax = 385, 460, 890 nm), Mössbauer (δ = 0.21, |ΔEQ| = 1.57 mm s-1), RR (ν(FeIV═O) = 735 cm-1), and X-ray absorption spectroscopies, as well as reactivity patterns. Reaction of 3 at low temperature with H atom donors gives a new species, FeIII(OH)(Me3TACN)(S2SiMe2) (4). Complex 4 was independently synthesized from 1 by the stoichiometric addition of a one-electron oxidant and a hydroxide source. This work provides a rare example of dioxygen activation at a mononuclear nonheme iron(II) complex that produces both FeIII-O-O-FeIII and FeIV(O) species in the same reaction with O2. It also demonstrates the feasibility of forming Fe/O2 intermediates with strongly donating sulfur ligands while avoiding immediate sulfur oxidation.
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Affiliation(s)
- Jesse B Gordon
- Department of Chemistry , The Johns Hopkins University , 3400 North Charles Street , Baltimore , Maryland 21218 , United States
| | - Avery C Vilbert
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853 , United States
| | - Ida M DiMucci
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853 , United States
| | - Samantha N MacMillan
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853 , United States
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853 , United States
| | - Pierre Moënne-Loccoz
- Department of Chemical Physiology and Biochemistry , Oregon Health & Science University , Portland , Oregon 97239 , United States
| | - David P Goldberg
- Department of Chemistry , The Johns Hopkins University , 3400 North Charles Street , Baltimore , Maryland 21218 , United States
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31
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Zerk TJ, Saouma CT, Mayer JM, Tolman WB. Low Reorganization Energy for Electron Self-Exchange by a Formally Copper(III,II) Redox Couple. Inorg Chem 2019; 58:14151-14158. [PMID: 31577145 DOI: 10.1021/acs.inorgchem.9b02185] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The rate constant for electron self-exchange (k11) between LCuOH and [LCuOH]- (L = bis-2,6-(2,6-diisopropylphenyl)carboximidopyridine) was determined using the Marcus cross relation. This work involved measurement of the rate of the cross-reaction between [Bu4N][LCuOH] and [Fc][BAr4F] (Fc+ = ferrocenium; BAr4F = tetrakis[3,5-bis(trifluoromethyl)phenyl]borate)) by stopped-flow methods at -88 °C in CH2Cl2 and measurement of the equilibrium constant for the redox process by UV-vis titrations under the same conditions. A value of k11 = 3 × 104 M-1 s-1 (-88 °C) led to estimation of a value 9 × 106 M-1 s-1 at 25 °C, which is among the highest values known for copper redox couples. Further Marcus analysis enabled determination of a low reorganization energy, λ = 0.95 ± 0.17 eV, attributed to minimal structural variation between the redox partners. In addition, the reaction entropy (ΔS°) associated with the LCuOH/[LCuOH]- self-exchange was determined from the temperature dependence of the redox potentials, and found to be dependent upon ionic strength. Comparisons to other Cu redox systems and potential new applications for the formally CuIII,II system are discussed.
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Affiliation(s)
- Timothy J Zerk
- Department of Chemistry , Washington University in St. Louis , One Brookings Hall, Campus Box 1134 , St. Louis , Missouri 63130-4899 , United States
| | - Caroline T Saouma
- Department of Chemistry , University of Utah , 315 S 1400 E , Salt Lake City , Utah 84112 , United States
| | - James M Mayer
- Department of Chemistry , Yale University , 225 Prospect Street , New Haven , Connecticut 06520-8107 , United States
| | - William B Tolman
- Department of Chemistry , Washington University in St. Louis , One Brookings Hall, Campus Box 1134 , St. Louis , Missouri 63130-4899 , United States
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32
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Quist DA, Ehudin MA, Schaefer AW, Schneider GL, Solomon EI, Karlin KD. Ligand Identity-Induced Generation of Enhanced Oxidative Hydrogen Atom Transfer Reactivity for a Cu II2(O 2•-) Complex Driven by Formation of a Cu II2( -OOH) Compound with a Strong O-H Bond. J Am Chem Soc 2019; 141:12682-12696. [PMID: 31299154 DOI: 10.1021/jacs.9b05277] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A superoxide-bridged dicopper(II) complex, [CuII2(XYLO)(O2•-)]2+ (1) (XYLO = binucleating m-xylyl derivative with a bridging phenolate ligand donor and two bis(2-{2-pyridyl}ethyl)amine arms), was generated from chemical oxidation of the peroxide-bridged dicopper(II) complex [CuII2(XYLO)(O22-)]+ (2), using ferrocenium (Fc+) derivatives, in 2-methyltetrahydrofuran (MeTHF) at -125 °C. Using Me10Fc+, a 1 ⇆ 2 equilibrium was established, allowing for calculation of the reduction potential of 1 as -0.525 ± 0.01 V vs Fc+/0. Addition of 1 equiv of strong acid to 2 afforded the hydroperoxide-bridged dicopper(II) species [CuII2(XYLO)(OOH)]2+ (3). An acid-base equilibrium between 3 and 2 was achieved through spectral titrations using a derivatized phosphazene base. The pKa of 3 was thus determined to be 24 ± 0.6 in MeTHF at -125 °C. Using a thermodynamic square scheme and the Bordwell relationship, the hydroperoxo complex (3) O-H bond dissociation free energy (BDFE) was calculated as 81.8 ± 1.5 (BDE = 86.8) kcal/mol. The observed oxidizing capability of [CuII2(XYLO)(O2•-)]2+ (1), as demonstrated in H atom abstraction reactions with certain phenolic ArO-H and hydrocarbon C-H substrates, provides direct support for this experimentally determined O-H BDFE. A kinetic study reveals a very fast reaction of TEMPO-H with 1 in MeTHF, with k (-100 °C) = 5.6 M-1 s-1. Density functional theory (DFT) calculations reveal how the structure of 1 may minimize stabilization of the superoxide moiety, resulting in its enhanced reactivity. The thermodynamic insights obtained herein highlight the importance of the interplay between ligand design and the generation and properties of copper (or other metal ion) bound O2-derived reduced species, such as pKa, reduction potential, and BDFE; these may be relevant to the capabilities (i.e., oxidizing power) of reactive oxygen intermediates in metalloenzyme chemical system mediated oxidative processes.
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Affiliation(s)
- David A Quist
- Department of Chemistry , Johns Hopkins University , Baltimore , Maryland 21218 , United States
| | - Melanie A Ehudin
- Department of Chemistry , Johns Hopkins University , Baltimore , Maryland 21218 , United States
| | - Andrew W Schaefer
- Department of Chemistry , Stanford University , Stanford , California 94305 , United States
| | - Gregory L Schneider
- Department of Chemistry , Stanford University , Stanford , California 94305 , United States
| | - Edward I Solomon
- Department of Chemistry , Stanford University , Stanford , California 94305 , United States
| | - Kenneth D Karlin
- Department of Chemistry , Johns Hopkins University , Baltimore , Maryland 21218 , United States
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Shi K, Mathivathanan L, Boudalis AK, Turek P, Chakraborty I, Raptis RG. Nitrite Reduction by Trinuclear Copper Pyrazolate Complexes: An Example of a Catalytic, Synthetic Polynuclear NO Releasing System. Inorg Chem 2019; 58:7537-7544. [DOI: 10.1021/acs.inorgchem.9b00748] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kaige Shi
- Department of Chemistry and Biochemistry and Biomolecular Sciences Institute, Florida International University, 11200 SW Eighth Street, Miami, Florida 33199, United States
| | - Logesh Mathivathanan
- Department of Chemistry and Biochemistry and Biomolecular Sciences Institute, Florida International University, 11200 SW Eighth Street, Miami, Florida 33199, United States
| | - Athanassios K. Boudalis
- Institut de Chimie UMR 7177/Université de Strasbourg 4, rue Blaise Pascal/CS 90032, F-67081 Strasbourg CEDEX, France
| | - Philippe Turek
- Institut de Chimie UMR 7177/Université de Strasbourg 4, rue Blaise Pascal/CS 90032, F-67081 Strasbourg CEDEX, France
| | - Indranil Chakraborty
- Department of Chemistry and Biochemistry and Biomolecular Sciences Institute, Florida International University, 11200 SW Eighth Street, Miami, Florida 33199, United States
| | - Raphael G. Raptis
- Department of Chemistry and Biochemistry and Biomolecular Sciences Institute, Florida International University, 11200 SW Eighth Street, Miami, Florida 33199, United States
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34
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Gordon JB, Vilbert AC, Siegler MA, Lancaster KM, Moënne-Loccoz P, Goldberg DP. A Nonheme Thiolate-Ligated Cobalt Superoxo Complex: Synthesis and Spectroscopic Characterization, Computational Studies, and Hydrogen Atom Abstraction Reactivity. J Am Chem Soc 2019; 141:3641-3653. [PMID: 30776222 DOI: 10.1021/jacs.8b13134] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The synthesis and characterization of a Co(II) dithiolato complex Co(Me3TACN)(S2SiMe2) (1) are reported. Reaction of 1 with O2 generates a rare thiolate-ligated cobalt-superoxo species Co(O2)(Me3TACN)(S2SiMe2) (2) that was characterized spectroscopically and structurally by resonance Raman, EPR, and X-ray absorption spectroscopies as well as density functional theory. Metal-superoxo species are proposed to S-oxygenate metal-bound thiolate donors in nonheme thiol dioxygenases, but 2 does not lead to S-oxygenation of the intramolecular thiolate donors and does not react with exogenous sulfur donors. However, complex 2 is capable of oxidizing the O-H bonds of 2,2,6,6-tetramethylpiperidin-1-ol derivatives via H atom abstraction. Complementary proton-coupled electron-transfer reactivity is seen for 2 with separated proton/reductant pairs. The reactivity studies indicate that 2 can abstract H atoms from weak X-H bonds with bond dissociation free energy (BDFE) ≤ 70 kcal mol-1. DFT calculations predict that the putative Co(OOH) product has an O-H BDFE = 67 kcal mol-1, which matches the observed pattern of reactivity seen for 2. These data provide new information regarding the selectivity of S-oxygenation versus H atom abstraction in thiolate-ligated nonheme metalloenzymes that react with O2.
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Affiliation(s)
- Jesse B Gordon
- Department of Chemistry , The Johns Hopkins University , 3400 North Charles Street , Baltimore , Maryland 21218 , United States
| | - Avery C Vilbert
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853 , United States
| | - Maxime A Siegler
- Department of Chemistry , The Johns Hopkins University , 3400 North Charles Street , Baltimore , Maryland 21218 , United States
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853 , United States
| | - Pierre Moënne-Loccoz
- Department of Biochemistry & Molecular Biology , Oregon Health & Science University , Portland , Oregon 97239-3098 , United States
| | - David P Goldberg
- Department of Chemistry , The Johns Hopkins University , 3400 North Charles Street , Baltimore , Maryland 21218 , United States
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35
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Zhao Y, Yu F, Wang C, Zhou Z. Simultaneous Formation of cis- and trans-CH3OCu(OH) Intermediates in Methane Activation by Cu in Solid Ar. Inorg Chem 2019; 58:3237-3246. [DOI: 10.1021/acs.inorgchem.8b03322] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Yanying Zhao
- Department of Chemistry and State Key Laboratory of Advanced Textiles Materials and Manufacture Technology, Ministry of Education, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Fan Yu
- Department of Chemistry and State Key Laboratory of Advanced Textiles Materials and Manufacture Technology, Ministry of Education, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Caixia Wang
- Department of Chemistry and State Key Laboratory of Advanced Textiles Materials and Manufacture Technology, Ministry of Education, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Zhaoman Zhou
- Department of Chemistry and State Key Laboratory of Advanced Textiles Materials and Manufacture Technology, Ministry of Education, Zhejiang Sci-Tech University, Hangzhou 310018, China
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36
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Elwell CE, Neisen BD, Tolman WB. Copper Complexes of Multidentate Carboxamide Ligands. Inorganica Chim Acta 2019; 485:131-139. [PMID: 31105329 DOI: 10.1016/j.ica.2018.10.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The copper coordination chemistry of two multidentate carboxamido ligands derived from HL1 (offering two quinolyl and one carboxamide donor) and H4L2 (with two pyridine(dicarboxamido) units linked by naphthalene spacers) was explored. The former was chosen because upon deprotonation it would provide a monoanionic mer-coordinating N-donor set that would model the putative deprotonated form of the His-brace in copper monooxygenases, while the latter was designed to bind two copper ions and enable comparisons to other systems with different ligand spacers. Upon reaction with Cu(I)-mesityl, HL1 yielded a symmetric dimer (L1Cu)2 in which each bis(quinolyl)amide ligand binds via two N-donors to one Cu(I) ion and via the third to the other Cu(I) center. Monomeric Cu(II) complexes [L 1 Cu(H 2 O) 2 ](OTf) and L 1 2 Cu were also characterized. Treatment of H4L2 with Cu(OTf)2 and excess Me4NOH (in CH3CN, pyridine/H2O, or MeOH) yielded complexes with anions of general formula [L 2 Cu 2 (X)]n-, where X = CH3CONH- (n = 1), CO3 2- (n = 2), or MeO- (n = 1). X-ray structures of these complexes revealed the (L2)4- ligand binding to two Cu(II) ions in an open paddle-wheel geometry, with an additional bridging ligand (X) completing the square planar coordination sphere of each metal ion. The open paddlewheel motif differs from the more 'open' puckered geometry seen with related ligands with different spacer units.
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Affiliation(s)
- Courtney E Elwell
- Department of Chemistry, University of Minnesota, 207 Pleasant St. SE, Minneapolis, MN 55455
| | - Benjamin D Neisen
- Department of Chemistry, University of Minnesota, 207 Pleasant St. SE, Minneapolis, MN 55455
| | - William B Tolman
- Department of Chemistry, Washington University in St. Louis, Campus Box 1134, 1 Brookings Drive, St. Louis, MO 63130
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Adam SM, Wijeratne GB, Rogler PJ, Diaz DE, Quist DA, Liu JJ, Karlin KD. Synthetic Fe/Cu Complexes: Toward Understanding Heme-Copper Oxidase Structure and Function. Chem Rev 2018; 118:10840-11022. [PMID: 30372042 PMCID: PMC6360144 DOI: 10.1021/acs.chemrev.8b00074] [Citation(s) in RCA: 145] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Heme-copper oxidases (HCOs) are terminal enzymes on the mitochondrial or bacterial respiratory electron transport chain, which utilize a unique heterobinuclear active site to catalyze the 4H+/4e- reduction of dioxygen to water. This process involves a proton-coupled electron transfer (PCET) from a tyrosine (phenolic) residue and additional redox events coupled to transmembrane proton pumping and ATP synthesis. Given that HCOs are large, complex, membrane-bound enzymes, bioinspired synthetic model chemistry is a promising approach to better understand heme-Cu-mediated dioxygen reduction, including the details of proton and electron movements. This review encompasses important aspects of heme-O2 and copper-O2 (bio)chemistries as they relate to the design and interpretation of small molecule model systems and provides perspectives from fundamental coordination chemistry, which can be applied to the understanding of HCO activity. We focus on recent advancements from studies of heme-Cu models, evaluating experimental and computational results, which highlight important fundamental structure-function relationships. Finally, we provide an outlook for future potential contributions from synthetic inorganic chemistry and discuss their implications with relevance to biological O2-reduction.
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Affiliation(s)
- Suzanne M. Adam
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Gayan B. Wijeratne
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Patrick J. Rogler
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Daniel E. Diaz
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - David A. Quist
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Jeffrey J. Liu
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Kenneth D. Karlin
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
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38
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Kotani H, Kaida S, Ishizuka T, Mieda K, Sakaguchi M, Ogura T, Shiota Y, Yoshizawa K, Kojima T. Importance of the Reactant-State Potentials of Chromium(V)–Oxo Complexes to Determine the Reactivity in Hydrogen-Atom Transfer Reactions. Inorg Chem 2018; 57:13929-13936. [DOI: 10.1021/acs.inorgchem.8b02453] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Hiroaki Kotani
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8571, Japan
| | - Suzue Kaida
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8571, Japan
| | - Tomoya Ishizuka
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8571, Japan
| | - Kaoru Mieda
- Graduate School of Life Science, University of Hyogo, Kouto, Hyogo 678-1297, Japan
| | - Miyuki Sakaguchi
- Graduate School of Life Science, University of Hyogo, Kouto, Hyogo 678-1297, Japan
| | - Takashi Ogura
- Graduate School of Life Science, University of Hyogo, Kouto, Hyogo 678-1297, Japan
| | - Yoshihito Shiota
- Institute for Materials Chemistry and Engineering, Kyushu University, Motooka, Nishi-Ku, Fukuoka 819-0395, Japan
| | - Kazunari Yoshizawa
- Institute for Materials Chemistry and Engineering, Kyushu University, Motooka, Nishi-Ku, Fukuoka 819-0395, Japan
- Elements Strategy Initiative for Catalysts & Batteries, Kyoto University, Nishi-ku, Kyoto 615-8520, Japan
| | - Takahiko Kojima
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8571, Japan
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39
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Dhar D, Yee GM, Tolman WB. Effects of Charged Ligand Substituents on the Properties of the Formally Copper(III)-Hydroxide ([CuOH] 2+) Unit. Inorg Chem 2018; 57:9794-9806. [PMID: 30070473 PMCID: PMC6653640 DOI: 10.1021/acs.inorgchem.8b01529] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
With the goal of understanding how distal charge influences the properties and hydrogen atom transfer (HAT) reactivity of the [CuOH]2+ core proposed to be important in oxidation catalysis, the complexes [M]3[SO3LCuOH] (M = [K(18-crown-6)]+ or [K(crypt-222)]+) and [NMe3LCuOH]X (X = BArF4- or ClO4-) were prepared, in which SO3- or NMe3+ substituents occupy the para positions of the flanking aryl rings of the supporting bis(carboxamide)pyridine ligands. Structural and spectroscopic characterization showed that the [CuOH]+ cores in the corresponding complexes were similar, but cyclic voltammetry revealed the E1/2 value for the [CuOH]2+/[CuOH]+ couple to be nearly 0.3 V more oxidizing for the [NMe3LCuOH]2+ than the [SO3LCuOH]- species, with the latter influenced by interactions between the distal -SO3- substituents and K+ or Na+ counterions. Chemical oxidations of the complexes generated the corresponding [CuOH]2+ species as evinced by UV-vis spectroscopy. The rates of HAT reactions of these species with 9,10-dihydroanthracene to yield the corresponding [Cu(OH2)]2+ complexes and anthracene were measured, and the thermodynamics of the processes were evaluated via determination of the bond dissociation enthalpies (BDEs) of the product O-H bonds. The HAT rate for [SO3LCuOH]- was found to be ∼150 times faster than that for [NMe3LCuOH]2+, despite finding approximately the same BDEs for the product O-H bonds. Rationales for these observations and new insights into the roles of supporting ligand attributes on the properties of the [CuOH]2+ unit are presented.
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Affiliation(s)
| | | | - William B. Tolman
- Department of Chemistry, Washington University in St. Louis, Campus Box 1134, 1 Brookings Drive, St. Louis, Missouri 63130, United States
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40
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41
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Goetz MK, Hill EA, Filatov AS, Anderson JS. Isolation of a Terminal Co(III)-Oxo Complex. J Am Chem Soc 2018; 140:13176-13180. [PMID: 30078327 DOI: 10.1021/jacs.8b07399] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Late transition metal oxo complexes with high d-electron counts have been implicated as intermediates in a wide variety of important catalytic reactions; however, their reactive nature has often significantly limited their study. While some examples of these species have been isolated and characterized, complexes with d-electron counts >4 are exceedingly rare. Here we report that use of a strongly donating tris(imidazol-2-ylidene)borate scaffold enables the isolation of two highly unusual CoIII-oxo complexes which have been thoroughly characterized by a suite of physical techniques including single crystal X-ray diffraction. These complexes display O atom and H atom transfer reactivity and demonstrate that terminal metal oxo complexes with six d-electrons can display strong metal-oxygen bonding and sufficient stability to enable their characterization. The unambiguous assignment of these complexes supports the viability of related species that are frequently invoked, but rarely observed, in the types of catalytic reactions mentioned above. The studies described here change our understanding of the reactivity and bonding in late transition metal oxo complexes and open the door to further study of the properties of this class of elusive and important intermediates.
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Affiliation(s)
- McKenna K Goetz
- Department of Chemistry , University of Chicago , Chicago , Illinois 60637 , United States
| | - Ethan A Hill
- Department of Chemistry , University of Chicago , Chicago , Illinois 60637 , United States
| | - Alexander S Filatov
- Department of Chemistry , University of Chicago , Chicago , Illinois 60637 , United States
| | - John S Anderson
- Department of Chemistry , University of Chicago , Chicago , Illinois 60637 , United States
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42
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Zaragoza JPT, Siegler MA, Goldberg DP. A Reactive Manganese(IV)-Hydroxide Complex: A Missing Intermediate in Hydrogen Atom Transfer by High-Valent Metal-Oxo Porphyrinoid Compounds. J Am Chem Soc 2018. [PMID: 29542921 DOI: 10.1021/jacs.8b00350] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
High-valent metal-hydroxide species are invoked as critical intermediates in both catalytic, metal-mediated O2 activation (e.g., by Fe porphyrin in Cytochrome P450) and O2 production (e.g., by the Mn cluster in Photosystem II). However, well-characterized mononuclear MIV(OH) complexes remain a rarity. Herein we describe the synthesis of MnIV(OH)(ttppc) (3) (ttppc = tris(2,4,6-triphenylphenyl) corrole), which has been characterized by X-ray diffraction (XRD). The large steric encumbrance of the ttppc ligand allowed for isolation of 3. The complexes MnV(O)(ttppc) (4) and MnIII(H2O)(ttppc) (1·H2O) were also synthesized and structurally characterized, providing a series of Mn complexes related only by the transfer of hydrogen atoms. Both 3 and 4 abstract an H atom from the O-H bond of 2,4-di- tert-butylphenol (2,4-DTBP) to give a radical coupling product in good yield (3 = 90(2)%, 4 = 91(5)%). Complex 3 reacts with 2,4-DTBP with a rate constant of k2 = 2.73(12) × 104 M-1 s-1, which is ∼3 orders of magnitude larger than 4 ( k2 = 17.4(1) M-1 s-1). Reaction of 3 with a series of para-substituted 2,6-di- tert-butylphenol derivatives (4-X-2,6-DTBP; X = OMe, Me, tBu, H) gives rate constants in the range k2 = 510(10)-36(1.4) M-1 s-1 and led to Hammett and Marcus plot correlations. Together with kinetic isotope effect measurements, it is concluded that O-H cleavage occurs by a concerted H atom transfer (HAT) mechanism and that the MnIV(OH) complex is a much more powerful H atom abstractor than the higher-valent MnV(O) complex, or even some FeIV(O) complexes.
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Affiliation(s)
- Jan Paulo T Zaragoza
- Department of Chemistry , The Johns Hopkins University , 3400 North Charles Street , Baltimore , Maryland 21218 , United States
| | - Maxime A Siegler
- Department of Chemistry , The Johns Hopkins University , 3400 North Charles Street , Baltimore , Maryland 21218 , United States
| | - David P Goldberg
- Department of Chemistry , The Johns Hopkins University , 3400 North Charles Street , Baltimore , Maryland 21218 , United States
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43
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Marín IM, Auffrant A. Phosphasalen vs. Salen Ligands: What Does the Phosphorus Change? Eur J Inorg Chem 2018. [DOI: 10.1002/ejic.201701210] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Irene Mustieles Marín
- LCM, CNRS-Ecole polytechnique; Université Paris-Saclay; F-91128 Palaiseau Cedex France
| | - Audrey Auffrant
- LCM, CNRS-Ecole polytechnique; Université Paris-Saclay; F-91128 Palaiseau Cedex France
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44
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Cheng Q, Fortenberry RC, DeYonker NJ. Towards a quantum chemical protocol for the prediction of rovibrational spectroscopic data for transition metal molecules: Exploration of CuCN, CuOH, and CuCCH. J Chem Phys 2017; 147:234303. [PMID: 29272934 DOI: 10.1063/1.5006931] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
High accuracy electronic structure computations for small transition metal-containing molecules have been a long term challenge. Due to coupling between electronic and nuclear wave functions, even experimental/theoretical identification of the ground electronic state requires tremendous efforts. Quartic force fields (QFFs) are effective ab initio tools for obtaining reliable anharmonic spectroscopic properties. However, the method that employs complete basis set limit extrapolation ("C"), consideration of core electron correlation ("cC"), and inclusion of scalar relativity ("R") to produce the energy points on the QFF, the composite CcCR methodology, has not yet been utilized to study inorganic spectroscopy. This work takes the CcCR methodology and adapts it to test whether such an approach is conducive for the closed-shell, copper-containing molecules CuCN, CuOH, and CuCCH. Gas phase rovibrational data are provided for all three species in their ground electronic states. Equilibrium geometries and many higher-order rovibrational properties show good agreement with earlier studies. However, there are notable differences, especially in computation of fundamental vibrational frequencies. Even with further additive corrections for the inner core electron correlation and coupled cluster with full single, double, and triple substitutions (CCSDT), the differences are still larger than expected indicating that more work should follow for predicting rovibrational properties of transition metal molecules.
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Affiliation(s)
- Qianyi Cheng
- Department of Chemistry, University of Memphis, Memphis, Tennessee 38152, USA
| | - Ryan C Fortenberry
- Department of Chemistry and Biochemistry, Georgia Southern University, Statesboro, Georgia 30460, USA
| | - Nathan J DeYonker
- Department of Chemistry, University of Memphis, Memphis, Tennessee 38152, USA
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45
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Mustieles Marín I, Cheisson T, Singh-Chauhan R, Herrero C, Cordier M, Clavaguéra C, Nocton G, Auffrant A. Electronic Structures of Mono-Oxidized Copper and Nickel Phosphasalen Complexes. Chemistry 2017; 23:17940-17953. [PMID: 28980736 DOI: 10.1002/chem.201703390] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Indexed: 11/11/2022]
Abstract
Non-innocent ligands render the determination of the electronic structure in metal complexes difficult. As such, a combination of experimental techniques and quantum chemistry are required to correctly elucidate them. This paper deals with the one-electron oxidation of copper(II) and nickel(II) complexes featuring a phosphasalen ligand (Psalen), which differs from salen analogues by the presence of iminophosphorane groups (P=N) instead of imines. Various experimental techniques (X-ray diffraction, cyclic voltammetry, NMR, EPR, and UV/Vis spectroscopies, and magnetic measurements) as well as quantum chemical calculations were used to define the electronic structure of the oxidized complexes. These can be modified by a small change in the ligand structure, that is, the replacement of a tert-butyl group by a methoxy on the phenoxide ring. The different techniques have allowed quantifying the amount of spin density located on the metal center and on the Psalen ligands. All complexes were found to possess a multi-configurational ground state, in which the ratio of the +II versus +III oxidation state of the metal center, and therefore the phenolate versus phenoxyl radical ligand character, varies upon the substituents. The tert-butyl group favors a strong localization on the metal center whereas with the methoxy group the metallic configurations decrease and the ligand configurations increase. The importance of the geometrical considerations compared with the electronic substituent effect is highlighted by the differences observed between the solid-state (EPR, magnetic measurements) and solution characterizations (EPR and NMR data).
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Affiliation(s)
- Irene Mustieles Marín
- LCM, CNRS-Ecole polytechnique, Université Paris-Saclay, 91128, Palaiseau Cedex, France
| | - Thibault Cheisson
- LCM, CNRS-Ecole polytechnique, Université Paris-Saclay, 91128, Palaiseau Cedex, France
| | - Rohit Singh-Chauhan
- LCM, CNRS-Ecole polytechnique, Université Paris-Saclay, 91128, Palaiseau Cedex, France
| | - Christian Herrero
- Institut de Chimie Moléculaire et des Matériaux d'Orsay, UMR 8182 CNRS-Univ. Paris-Sud, Univ. Paris Saclay, 91405, Orsay Cedex, France
| | - Marie Cordier
- LCM, CNRS-Ecole polytechnique, Université Paris-Saclay, 91128, Palaiseau Cedex, France
| | - Carine Clavaguéra
- LCM, CNRS-Ecole polytechnique, Université Paris-Saclay, 91128, Palaiseau Cedex, France.,Laboratoire de Chimie Physique, CNRS-Université Paris-Sud, Université Paris-Saclay, 15 avenue Jean Perrin, 91405, Orsay, France
| | - Grégory Nocton
- LCM, CNRS-Ecole polytechnique, Université Paris-Saclay, 91128, Palaiseau Cedex, France
| | - Audrey Auffrant
- LCM, CNRS-Ecole polytechnique, Université Paris-Saclay, 91128, Palaiseau Cedex, France
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Zaragoza JPT, Yosca TH, Siegler MA, Möenne-Loccoz P, Green MT, Goldberg DP. Direct Observation of Oxygen Rebound with an Iron-Hydroxide Complex. J Am Chem Soc 2017; 139:13640-13643. [PMID: 28930448 PMCID: PMC6058725 DOI: 10.1021/jacs.7b07979] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The rebound mechanism for alkane hydroxylation was invoked over 40 years ago to help explain reactivity patterns in cytochrome P450, and subsequently has been used to provide insight into a range of biological and synthetic systems. Efforts to model the rebound reaction in a synthetic system have been unsuccessful, in part because of the challenge in preparing a suitable metal-hydroxide complex at the correct oxidation level. Herein we report the synthesis of such a complex. The reaction of this species with a series of substituted radicals allows for the direct interrogation of the rebound process, providing insight into this uniformly invoked, but previously unobserved process.
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Affiliation(s)
- Jan Paulo T. Zaragoza
- Department of Chemistry, The Johns Hopkins University, 3400 N Charles Street, Baltimore, Maryland 21218, United States
| | - Timothy H. Yosca
- Department of Chemistry, University of California–Irvine, 1102 Natural Sciences II, Irvine, California 92697, United States
| | - Maxime A. Siegler
- Department of Chemistry, The Johns Hopkins University, 3400 N Charles Street, Baltimore, Maryland 21218, United States
| | - Pierre Möenne-Loccoz
- Institute of Environmental Health, Oregon Health & Science University, Portland, Oregon 97239, United States
| | - Michael T. Green
- Department of Chemistry, University of California–Irvine, 1102 Natural Sciences II, Irvine, California 92697, United States
| | - David P. Goldberg
- Department of Chemistry, The Johns Hopkins University, 3400 N Charles Street, Baltimore, Maryland 21218, United States
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47
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Neisen BD, Gagnon NL, Dhar D, Spaeth AD, Tolman WB. Formally Copper(III)-Alkylperoxo Complexes as Models of Possible Intermediates in Monooxygenase Enzymes. J Am Chem Soc 2017; 139:10220-10223. [PMID: 28722408 DOI: 10.1021/jacs.7b05754] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Reaction of [NBu4][LCuIIOH] with excess ROOH (R = cumyl or tBu) yielded [NBu4][LCuIIOOR], the reversible one-electron oxidation of which generated novel species with [CuOOR]2+ cores (formally CuIIIOOR), identified by spectroscopy and theory for the case R = cumyl. This species reacts with weak O-H bonds in TEMPO-H and 4-dimethylaminophenol (NMe2PhOH), the latter yielding LCu(OPhNMe2), which was also prepared independently. With the identification of [CuOOR]2+ complexes, the first precedent for this core in enzymes is provided, with implications for copper monooxygenase mechanisms.
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Affiliation(s)
- Benjamin D Neisen
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - Nicole L Gagnon
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - Debanjan Dhar
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - Andrew D Spaeth
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - William B Tolman
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
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