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Pagès-Vilà N, Gamba I, Clémancey M, Latour JM, Company A, Costas M. Proton-triggered chemoselective halogenation of aliphatic C-H bonds with nonheme Fe IV-oxo complexes. J Inorg Biochem 2024; 259:112643. [PMID: 38924872 DOI: 10.1016/j.jinorgbio.2024.112643] [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: 04/26/2024] [Revised: 05/30/2024] [Accepted: 06/14/2024] [Indexed: 06/28/2024]
Abstract
Halogenation of aliphatic C-H bonds is a chemical transformation performed in nature by mononuclear nonheme iron dependent halogenases. The mechanism involves the formation of an iron(IV)-oxo-chloride species that abstracts the hydrogen atom from the reactive C-H bond to form a carbon-centered radical that selectively reacts with the bound chloride ligand, a process commonly referred to as halide rebound. The factors that determine the halide rebound, as opposed to the reaction with the incipient hydroxide ligand, are not clearly understood and examples of well-defined iron(IV)-oxo-halide compounds competent in C-H halogenation are scarce. In this work we have studied the reactivity of three well-defined iron(IV)-oxo complexes containing variants of the tetradentate 1-(2-pyridylmethyl)-1,4,7-triazacyclononane ligand (Pytacn). Interestingly, these compounds exhibit a change in their chemoselectivity towards the functionalization of C-H bonds under certain conditions: their reaction towards C-H bonds in the presence of a halide anionleads to exclusive oxygenation, while the addition of a superacid results in halogenation. Almost quantitative halogenation of ethylbenzene is observed when using the two systems with more sterically congested ligands and even the chlorination of strong C-H bonds such as those of cyclohexane is performed when a methyl group is present in the sixth position of the pyridine ring of the ligand. Mechanistic studies suggest that both reactions, oxygenation and halogenation, proceed through a common rate determining hydrogen atom transfer step and the presence of the acid dictates the fate of the resulting alkyl radical towards preferential halogenation over oxygenation.
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Affiliation(s)
- Neus Pagès-Vilà
- Institut de Química Computacional i Catàlisi (IQCC), Departament de Química, Universitat de Girona, C/ Maria Aurèlia Capmany 69, 17003 Girona, Catalonia, Spain
| | - Ilaria Gamba
- Institut de Química Computacional i Catàlisi (IQCC), Departament de Química, Universitat de Girona, C/ Maria Aurèlia Capmany 69, 17003 Girona, Catalonia, Spain; Departamento de Química, Facultad de Ciencias, Universidad de La Laguna, Av. Astrofísico Sánchez s/n, 38200 La Laguna, Spain.
| | - Martin Clémancey
- Univ. Grenoble Alpes, CNRS, CEA, IRIG, Laboratoire de Chimie et Biologie des Métaux, F-38000 Grenoble, France
| | - Jean-Marc Latour
- Univ. Grenoble Alpes, CNRS, CEA, IRIG, Laboratoire de Chimie et Biologie des Métaux, F-38000 Grenoble, France
| | - Anna Company
- Institut de Química Computacional i Catàlisi (IQCC), Departament de Química, Universitat de Girona, C/ Maria Aurèlia Capmany 69, 17003 Girona, Catalonia, Spain.
| | - Miquel Costas
- Institut de Química Computacional i Catàlisi (IQCC), Departament de Química, Universitat de Girona, C/ Maria Aurèlia Capmany 69, 17003 Girona, Catalonia, Spain.
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2
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Yue D, Hirao H. Enhancing the high-spin reactivity in C-H bond activation by Iron (IV)-Oxo species: insights from paclitaxel hydroxylation by CYP2C8. Front Chem 2024; 12:1471741. [PMID: 39345859 PMCID: PMC11427847 DOI: 10.3389/fchem.2024.1471741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2024] [Accepted: 08/26/2024] [Indexed: 10/01/2024] Open
Abstract
Previous theoretical studies have revealed that high-spin states possess flatter potential energy surfaces than low-spin states in reactions involving iron(IV)-oxo species of cytochrome P450 enzymes (P450s), nonheme enzymes, or biomimetic complexes. Therefore, actively utilizing high-spin states to enhance challenging chemical transformations, such as C-H bond activation, represents an intriguing research avenue. However, the inherent instability of high-spin states relative to low-spin states in pre-reaction complexes often hinders their accessibility around the transition state, especially in heme systems with strong ligand fields. Counterintuitively, our investigation of the metabolic hydroxylation of paclitaxel by human CYP2C8 using a hybrid quantum mechanics and molecular mechanics (QM/MM) approach showed that the high-spin sextet state exhibits unusually high stability, when the reaction follows a secondary reaction pathway leading to 6β-hydroxypaclitaxel. We thoroughly analyzed the factors contributing to the enhanced stabilization of the high-spin state, and the knowledge obtained could be instrumental in designing competent biomimetic catalysts and biocatalysts for C-H bond activation.
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Affiliation(s)
| | - Hajime Hirao
- Warshel Institute for Computational Biology, School of Medicine, The Chinese University of Hong Kong, Shenzhen, China
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3
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Bhardwaj A, Mondal B. Unraveling the Geometry-Driven C═C Epoxidation and C-H Hydroxylation Reactivity of Tetra-Coordinated Nonheme Iron(IV)-Oxo Complexes. Inorg Chem 2024; 63:14468-14481. [PMID: 39030661 DOI: 10.1021/acs.inorgchem.4c01708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/21/2024]
Abstract
The electronic structure and reactivity of tetra-coordinated nonheme iron(IV)-oxo complexes have remained unexplored for years. The recent synthesis of a closed-shell iron(IV)-oxo complex [(quinisox)FeIV(O)]+ (1) has set up a platform to understand how such complexes compare with the celebrated open-shell iron-oxo chemistry. Herein, using density functional theory and ab initio calculations, we present an in-depth electronic structure investigation of the C═C epoxidation [oxygen atom transfer (OAT)] and C-H hydroxylation [hydrogen atom transfer (HAT)] reactivity of 1. Using a solvent-coordinated geometry of 1 (1') and other potential tetra-coordinated iron(IV)-oxo complexes bearing rigid ligands (2 and 3), we established the geometric origin of spin-state energetics and reactivity of 1. Complex 1 featuring a strong Fe-O bond exhibits OAT and HAT reactivity in its quintet state. The lowest quintet OAT pathway has a lower barrier by ∼4 kcal/mol than the quintet HAT pathway, corroborating the experimentally observed gas-phase OAT reactivity preference. A conventional HAT reactivity preference for 2 and a comparable OAT and HAT reactivity for 3 are observed. This further supports the geometry-driven reactivity preference for 1. Noncovalent interaction analyses reveal a pronounced π-π interaction between the substrate and ligand in the OAT transition state, rationalizing the origin of the observed reactivity preference for 1.
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Affiliation(s)
- Akhil Bhardwaj
- School of Chemical Sciences, Indian Institute of Technology Mandi, Mandi, Himachal Pradesh 175075, India
| | - Bhaskar Mondal
- School of Chemical Sciences, Indian Institute of Technology Mandi, Mandi, Himachal Pradesh 175075, India
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4
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Rice DB, Wong D, Weyhermüller T, Neese F, DeBeer S. The spin-forbidden transition in iron(IV)-oxo catalysts relevant to two-state reactivity. SCIENCE ADVANCES 2024; 10:eado1603. [PMID: 38941457 PMCID: PMC11212722 DOI: 10.1126/sciadv.ado1603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Accepted: 05/23/2024] [Indexed: 06/30/2024]
Abstract
Quintet oxoiron(IV) intermediates are often invoked in nonheme iron enzymes capable of performing selective oxidation, while most well-characterized synthetic model oxoiron(IV) complexes have a triplet ground state. These differing spin states lead to the proposal of a two-state reactivity model, where the complexes cross from the triplet to an excited quintet state. However, the energy of this quintet state has never been measured experimentally. Here, magnetic circular dichroism is used to assign the singlet and triplet excited states in a series of triplet oxoiron(IV) complexes. These transition energies are used to determine the energies of the quintet state via constrained fitting of 2p3d resonant inelastic x-ray scattering. This allowed for a direct correlation between the quintet energies and substrate C─H oxidation rates.
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Affiliation(s)
- Derek B. Rice
- Max Planck Institute for Chemical Energy Conversion, D-45470 Mülheim an der Ruhr, Germany
| | - Deniz Wong
- Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, D-14109 Berlin, Germany
| | - Thomas Weyhermüller
- Max Planck Institute for Chemical Energy Conversion, D-45470 Mülheim an der Ruhr, Germany
| | - Frank Neese
- Max-Planck-Institut für Kohlenforschung, D-45470 Mülheim an der Ruhr, Germany
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, D-45470 Mülheim an der Ruhr, Germany
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5
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Cao Y, Hay S, de Visser SP. An Active Site Tyr Residue Guides the Regioselectivity of Lysine Hydroxylation by Nonheme Iron Lysine-4-hydroxylase Enzymes through Proton-Coupled Electron Transfer. J Am Chem Soc 2024; 146:11726-11739. [PMID: 38636166 PMCID: PMC11066847 DOI: 10.1021/jacs.3c14574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 04/05/2024] [Accepted: 04/05/2024] [Indexed: 04/20/2024]
Abstract
Lysine dioxygenase (KDO) is an important enzyme in human physiology involved in bioprocesses that trigger collagen cross-linking and blood pressure control. There are several KDOs in nature; however, little is known about the factors that govern the regio- and stereoselectivity of these enzymes. To understand how KDOs can selectively hydroxylate their substrate, we did a comprehensive computational study into the mechanisms and features of 4-lysine dioxygenase. In particular, we selected a snapshot from the MD simulation on KDO5 and created large QM cluster models (A, B, and C) containing 297, 312, and 407 atoms, respectively. The largest model predicts regioselectivity that matches experimental observation with rate-determining hydrogen atom abstraction from the C4-H position, followed by fast OH rebound to form 4-hydroxylysine products. The calculations show that in model C, the dipole moment is positioned along the C4-H bond of the substrate and, therefore, the electrostatic and electric field perturbations of the protein assist the enzyme in creating C4-H hydroxylation selectivity. Furthermore, an active site Tyr233 residue is identified that reacts through proton-coupled electron transfer akin to the axial Trp residue in cytochrome c peroxidase. Thus, upon formation of the iron(IV)-oxo species in the catalytic cycle, the Tyr233 phenol loses a proton to the nearby Asp179 residue, while at the same time, an electron is transferred to the iron to create an iron(III)-oxo active species. This charged tyrosyl residue directs the dipole moment along the C4-H bond of the substrate and guides the selectivity to the C4-hydroxylation of the substrate.
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Affiliation(s)
- Yuanxin Cao
- Manchester
Institute of Biotechnology, The University
of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
- Department
of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Sam Hay
- Manchester
Institute of Biotechnology, The University
of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
- Department
of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Sam P. de Visser
- Manchester
Institute of Biotechnology, The University
of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
- Department
of Chemical Engineering, The University
of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
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6
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Singh P, Massie AA, Denler MC, Lee Y, Mayfield JR, Lomax MJA, Singh R, Nordlander E, Jackson TA. C-H Bond Oxidation by Mn IV-Oxo Complexes: Hydrogen-Atom Tunneling and Multistate Reactivity. Inorg Chem 2024; 63:7754-7769. [PMID: 38625043 DOI: 10.1021/acs.inorgchem.4c00186] [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
The reactivity of six MnIV-oxo complexes in C-H bond oxidation has been examined using a combination of kinetic experiments and computational methods. Variable-temperature studies of the oxidation of 9,10-dihydroanthracene (DHA) and ethylbenzene by these MnIV-oxo complexes yielded activation parameters suitable for evaluating electronic structure computations. Complementary kinetic experiments of the oxidation of deuterated DHA provided evidence for hydrogen-atom tunneling in C-H bond oxidation for all MnIV-oxo complexes. These results are in accordance with the Bell model, where tunneling occurs near the top of the transition-state barrier. Density functional theory (DFT) and DLPNO-CCSD(T1) computations were performed for three of the six MnIV-oxo complexes to probe a previously predicted multistate reactivity model. The DFT computations predicted a thermal crossing from the 4B1 ground state to a 4E state along the C-H bond oxidation reaction coordinate. DLPNO-CCSD(T1) calculations further confirm that the 4E transition state offers a lower energy barrier, reinforcing the multistate reactivity model for these complexes. We discuss how this multistate model can be reconciled with recent computations that revealed that the kinetics of C-H bond oxidation by this set of MnIV-oxo complexes can be well-predicted on the basis of the thermodynamic driving force for these reactions.
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Affiliation(s)
- Priya Singh
- The University of Kansas, Department of Chemistry and Center for Environmentally Beneficial Catalysis, 1567 Irving Hill Road, Lawrence, Kansas 66045, United States
| | - Allyssa A Massie
- The University of Kansas, Department of Chemistry and Center for Environmentally Beneficial Catalysis, 1567 Irving Hill Road, Lawrence, Kansas 66045, United States
| | - Melissa C Denler
- The University of Kansas, Department of Chemistry and Center for Environmentally Beneficial Catalysis, 1567 Irving Hill Road, Lawrence, Kansas 66045, United States
| | - Yuri Lee
- The University of Kansas, Department of Chemistry and Center for Environmentally Beneficial Catalysis, 1567 Irving Hill Road, Lawrence, Kansas 66045, United States
| | - Jaycee R Mayfield
- The University of Kansas, Department of Chemistry and Center for Environmentally Beneficial Catalysis, 1567 Irving Hill Road, Lawrence, Kansas 66045, United States
| | - Markell J A Lomax
- The University of Kansas, Department of Chemistry and Center for Environmentally Beneficial Catalysis, 1567 Irving Hill Road, Lawrence, Kansas 66045, United States
| | - Reena Singh
- Lund University, Chemical Physics, Department of Chemistry, P.O. Box 124, SE-221 00 Lund, Sweden
| | - Ebbe Nordlander
- Lund University, Chemical Physics, Department of Chemistry, P.O. Box 124, SE-221 00 Lund, Sweden
| | - Timothy A Jackson
- The University of Kansas, Department of Chemistry and Center for Environmentally Beneficial Catalysis, 1567 Irving Hill Road, Lawrence, Kansas 66045, United States
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7
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Hardy FG, Wong HPH, de Visser SP. Computational Study Into the Oxidative Ring-Closure Mechanism During the Biosynthesis of Deoxypodophyllotoxin. Chemistry 2024; 30:e202400019. [PMID: 38323740 DOI: 10.1002/chem.202400019] [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: 01/03/2024] [Revised: 02/01/2024] [Accepted: 02/07/2024] [Indexed: 02/08/2024]
Abstract
The nonheme iron dioxygenase deoxypodophyllotoxin synthase performs an oxidative ring-closure reaction as part of natural product synthesis in plants. How the enzyme enables the oxidative ring-closure reaction of (-)-yatein and avoids substrate hydroxylation remains unknown. To gain insight into the reaction mechanism and understand the details of the pathways leading to products and by-products we performed a comprehensive computational study. The work shows that substrate is bound tightly into the substrate binding pocket with the C7'-H bond closest to the iron(IV)-oxo species. The reaction proceeds through a radical mechanism starting with hydrogen atom abstraction from the C7'-H position followed by ring-closure and a final hydrogen transfer to form iron(II)-water and deoxypodophyllotoxin. Alternative mechanisms including substrate hydroxylation and an electron transfer pathway were explored but found to be higher in energy. The mechanism is guided by electrostatic perturbations of charged residues in the second-coordination sphere that prevent alternative pathways.
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Affiliation(s)
- Fintan G Hardy
- Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
- Department of Chemical Engineering, The University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - Henrik P H Wong
- Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
- Department of Chemical Engineering, The University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - Sam P de Visser
- Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
- Department of Chemical Engineering, The University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
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Ahmed M, Malhotra SS, Yadav O, Monika, Saini C, Sharma N, Gupta MK, Mohapatra RK, Ansari A. DFT and TDDFT exploration on electronic transitions and bonding aspect of DPA and PTDC ligated transition metal complexes. J Mol Model 2024; 30:122. [PMID: 38570356 DOI: 10.1007/s00894-024-05912-5] [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: 02/18/2024] [Accepted: 03/22/2024] [Indexed: 04/05/2024]
Abstract
CONTEXT In this study, we have investigated the structure, reactivity, bonding, and electronic transitions of DPA and PDTC along with their Ni-Zn complexes using DFT/TD-DFT methods. The energy gap between the frontier orbitals was computed to understand the reactivity pattern of the ligands and metal complexes. From the energies of FMO's, the global reactivity descriptors such as electron affinity, ionization potential, hardness (η), softness (S), chemical potential (μ), electronegativity (χ), and electrophilicity index (ω) have been calculated. The complexes show a strong NLO properties due to easily polarization as indicated by the narrow HOMO-LUMO gap. The polarizability and hyperpolarizabilities of the complexes indicate that they are good candidates for NLO materials. Molecular electrostatic potential (MEP) maps identified electrophilic and nucleophilic sites on the surfaces of the complexes. TDDFT and NBO analyses provided insights into electronic transitions, bonding, and stabilizing interactions within the studied complexes. DPA and PDTC exhibited larger HOMO-LUMO gaps and more negative electrostatic potentials compared to their metal complexes suggesting the higher reactivity. Ligands (DPA and PDTC) had absorption spectra in the range of 250 nm to 285 nm while their complexes spanned 250 nm to 870 nm. These bands offer valuable information on electronic transitions, charge transfer and optical behavior. This work enhances our understanding of the electronic structure and optical properties of these complexes. METHODS Gaussian16 program was used for the optimization of all the compounds. B3LYP functional in combination with basis sets, such as LanL2DZ for Zn, Ni and Cu while 6-311G** for other atoms like C, H, O, N, and S was used. Natural bond orbital (NBO) analysis is carried out to find out how the filled orbital of one sub-system interacts with the empty orbital of another sub-system. The ORCA software is used for computing spectral features along with the zeroth order regular approximation method (ZORA) to observe its relativistic effects. TD-DFT study is carried out to calculate the excitation energy by using B3LYP functional.
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Affiliation(s)
- Mukhtar Ahmed
- Department of Chemistry, Central University of Haryana, Mahendergarh, 123031, India
| | - Sumit Sahil Malhotra
- Department of Chemistry, Central University of Haryana, Mahendergarh, 123031, India
| | - Oval Yadav
- Department of Chemistry, Central University of Haryana, Mahendergarh, 123031, India
| | - Monika
- Department of Chemistry, Central University of Haryana, Mahendergarh, 123031, India
| | - Charu Saini
- Department of Chemistry, Central University of Haryana, Mahendergarh, 123031, India
| | - Neha Sharma
- Life Science, Dyal Singh College, University of Delhi, Delhi, 110003, India
| | - Manoj Kumar Gupta
- Department of Chemistry, Central University of Haryana, Mahendergarh, 123031, India
| | - Ranjan Kumar Mohapatra
- Department of Chemistry, Government College of Engineering, Keonjhar, Odisha, 758002, India
| | - Azaj Ansari
- Department of Chemistry, Central University of Haryana, Mahendergarh, 123031, India.
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Vennelakanti V, Jeon M, Kulik HJ. How Do Differences in Electronic Structure Affect the Use of Vanadium Intermediates as Mimics in Nonheme Iron Hydroxylases? Inorg Chem 2024; 63:4997-5011. [PMID: 38428015 DOI: 10.1021/acs.inorgchem.3c04421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2024]
Abstract
We study active-site models of nonheme iron hydroxylases and their vanadium-based mimics using density functional theory to determine if vanadyl is a faithful structural mimic. We identify crucial structural and energetic differences between ferryl and vanadyl isomers owing to the differences in their ground electronic states, i.e., high spin (HS) for Fe and low spin (LS) for V. For the succinate cofactor bound to the ferryl intermediate, we predict facile interconversion between monodentate and bidentate coordination isomers for ferryl species but difficult rearrangement for vanadyl mimics. We study isomerization of the oxo intermediate between axial and equatorial positions and find the ferryl potential energy surface to be characterized by a large barrier of ca. 10 kcal/mol that is completely absent for the vanadyl mimic. This analysis reveals even starker contrasts between Fe and V in hydroxylases than those observed for this metal substitution in nonheme halogenases. Analysis of the relative bond strengths of coordinating carboxylate ligands for Fe and V reveals that all of the ligands show stronger binding to V than Fe owing to the LS ground state of V in contrast to the HS ground state of Fe, highlighting the limitations of vanadyl mimics of native nonheme iron hydroxylases.
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Affiliation(s)
- Vyshnavi Vennelakanti
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Mugyeom Jeon
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Heather J Kulik
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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Mahajan M, Mondal B. How Axial Coordination Regulates the Electronic Structure and C-H Amination Reactivity of Fe-Porphyrin-Nitrene? JACS AU 2023; 3:3494-3505. [PMID: 38155653 PMCID: PMC10751768 DOI: 10.1021/jacsau.3c00670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 11/22/2023] [Accepted: 11/27/2023] [Indexed: 12/30/2023]
Abstract
Detailed electronic structure and its correlation with the intramolecular C-H amination reactivity of Fe-porphyrin-nitrene intermediates bearing different "axial" coordination have been investigated using multiconfigurational complete active space self-consistent field (CASSCF), N-electron valence perturbation theory (NEVPT2), and hybrid density functional theory (DFT-B3LYP) calculations. Three types of "axial" coordination, -OMe/-O(H)Me (1-Sul/2-Sul), -SMe/-S(H)Me (3-Sul/4-Sul), and -NMeIm (MeIm = 3-methyl-imidazole) (5-Sul) mimicking serine, cysteine, and histidine, respectively, along with no axial coordination (6-Sul) have been considered to decipher how the "axial" coordination of different strengths regulates the electronic integrity of the Fe-N core and nitrene-transfer reactivity of Fe-porphyrin-nitrene intermediates. CASSCF-based natural orbitals reveal two distinct classes of electronic structures: Fe-nitrenes (1-Sul and 3-Sul) with relatively stronger axial coordination (-OMe and -SMe) display "imidyl" nature and those (2-Sul, 4-Sul, and 6-Sul) with weaker axial coordination (-O(H)Me, -S(H)Me and no axial coordination) exhibit "imido-like" character. A borderline between the two classes is also observed with NMeIm axial coordination (5-Sul). Axial coordination of different strengths not only regulates the electronic structure but also modulates the Fe-3d orbital energies, as revealed through the d-d transition energies obtained by CASSCF/NEVPT2 calculations. The relatively lower energy of Fe-3dz2 orbital allows easy access to low-lying high-spin quintet states in the cases of weaker "axial" coordination (2-Sul, 4-Sul, and 6-Sul), and the associated hydrogen atom transfer (HAT) reactivity appears to involve two-state triplet-quintet reactivity through minimum energy crossing point (3,5MECP) between the spin states. In stark contrast, Fe-nitrenes with relatively stronger "axial" coordination (1-Sul and 3-Sul) undergo triplet-only HAT reactivity. Overall, this in-depth electronic structure investigation and HAT reactivity evaluation reveal that the weaker axial coordination in Fe-porphyrin-nitrene complexes (2-Sul, 4-Sul, and 6-Sul) can promote more efficient C-H oxidation through the quintet spin state.
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Affiliation(s)
- Mayank Mahajan
- School of Chemical Sciences, Indian Institute of Technology Mandi, Mandi, Himachal Pradesh 175075, India
| | - Bhaskar Mondal
- School of Chemical Sciences, Indian Institute of Technology Mandi, Mandi, Himachal Pradesh 175075, India
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11
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Yamaguchi K, Isobe H, Shoji M, Kawakami T, Miyagawa K. The Nature of the Chemical Bonds of High-Valent Transition-Metal Oxo (M=O) and Peroxo (MOO) Compounds: A Historical Perspective of the Metal Oxyl-Radical Character by the Classical to Quantum Computations. Molecules 2023; 28:7119. [PMID: 37894598 PMCID: PMC10609222 DOI: 10.3390/molecules28207119] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 10/08/2023] [Accepted: 10/10/2023] [Indexed: 10/29/2023] Open
Abstract
This review article describes a historical perspective of elucidation of the nature of the chemical bonds of the high-valent transition metal oxo (M=O) and peroxo (M-O-O) compounds in chemistry and biology. The basic concepts and theoretical backgrounds of the broken-symmetry (BS) method are revisited to explain orbital symmetry conservation and orbital symmetry breaking for the theoretical characterization of four different mechanisms of chemical reactions. Beyond BS methods using the natural orbitals (UNO) of the BS solutions, such as UNO CI (CC), are also revisited for the elucidation of the scope and applicability of the BS methods. Several chemical indices have been derived as the conceptual bridges between the BS and beyond BS methods. The BS molecular orbital models have been employed to explain the metal oxyl-radical character of the M=O and M-O-O bonds, which respond to their radical reactivity. The isolobal and isospin analogy between carbonyl oxide R2C-O-O and metal peroxide LFe-O-O has been applied to understand and explain the chameleonic chemical reactivity of these compounds. The isolobal and isospin analogy among Fe=O, O=O, and O have also provided the triplet atomic oxygen (3O) model for non-heme Fe(IV)=O species with strong radical reactivity. The chameleonic reactivity of the compounds I (Cpd I) and II (Cpd II) is also explained by this analogy. The early proposals obtained by these theoretical models have been examined based on recent computational results by hybrid DFT (UHDFT), DLPNO CCSD(T0), CASPT2, and UNO CI (CC) methods and quantum computing (QC).
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Affiliation(s)
- Kizashi Yamaguchi
- SANKEN, Osaka University, Ibaraki 567-0047, Osaka, Japan
- Center for Quantum Information and Quantum Biology (QIQB), Osaka University, Toyonaka 560-0043, Osaka, Japan
| | - Hiroshi Isobe
- Research Institute for Interdisciplinary Science, Okayama University, Okayama 700-8530, Okayama, Japan;
| | - Mitsuo Shoji
- Center for Computational Sciences, University of Tsukuba, Tsukuba 305-8577, Ibaraki, Japan; (M.S.); (K.M.)
| | - Takashi Kawakami
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka 560-0043, Osaka, Japan;
| | - Koichi Miyagawa
- Center for Computational Sciences, University of Tsukuba, Tsukuba 305-8577, Ibaraki, Japan; (M.S.); (K.M.)
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12
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Sen A, Ansari A, Swain A, Pandey B, Rajaraman G. Probing the Origins of Puzzling Reactivity in Fe/Mn-Oxo/Hydroxo Species toward C-H Bonds: A DFT and Ab Initio Perspective. Inorg Chem 2023; 62:14931-14941. [PMID: 37650771 DOI: 10.1021/acs.inorgchem.3c01632] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Activation of C-H bonds using an earth-abundant metal catalyst is one of the top challenges of chemistry, where high-valent Mn/Fe-oxo(hydroxo) biomimic species play an important role. There are several open questions related to the comparative oxidative abilities of these species, and a unifying concept that could accommodate various factors influencing reactivity is lacking. To shed light on these open questions, here, we have used a combination of density functional theory (DFT) (B3LYP-D3/def2-TZVP) and ab initio (CASSCF/NEVPT2) calculations to study a series of high-valent metal-oxo species [Mn+H3buea(O/OH)] (M = Mn and Fe, n = II to V; H3buea = tris[(N'-tert-butylureaylato)-N-ethylene)]aminato towards the activation of dihydroanthracene (DHA). The H-bonding network in the ligand architecture influences the ground state-excited state gap and brings several excited states of the same spin multiplicity closer in energy, which triggers reactivity via one of those excited states, reducing the kinetic barriers for the C-H bond activation and rationalizing several puzzling reactivity trends observed in various high-valent Mn/Fe-oxo(hydroxo) species.
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Affiliation(s)
- Asmita Sen
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai400076, India
| | - Azaj Ansari
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai400076, India
| | - Abinash Swain
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai400076, India
| | - Bhawana Pandey
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai400076, India
| | - Gopalan Rajaraman
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai400076, India
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13
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Lewis TWR, Mastin EM, Theis ZC, Okafor SU, Gutierrez MG, Bellert DJ. Two state reactivity (TSR) and hydrogen tunneling reaction kinetics measured in the Co + mediated decomposition of CH 3CHO. Phys Chem Chem Phys 2023; 25:23477-23490. [PMID: 37646145 DOI: 10.1039/d2cp05042k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
The electronic structure of a transition metal atom allows it to act as a catalytic active site by providing lower energy alternative pathways in chemical transformations. We have identified and kinetically characterized three such pathways in the title reaction. One is an adiabatic pathway that occurs on a single potential energy surface described within the Born-Oppenheimer approximation. A second pathway opens microseconds into the reaction as a portion of the reacting population competitively transitions from triplet to singlet multiplicity to circumvent energetic barriers on the triplet surface. These pathways are single- and two-state reactive (SSR and TSR) where the Co+ cation mediates an oxidative addition/reductive elimination sequence of the CH3CHO molecule. The third observed reaction pathway is the aldehyde hydrogen tunneling through an Eyring barrier to form high-spin products. First-order rate constants for the adiabatic and nonadiabatic energy lowered pathways, and the hydrogen tunneling pathway, are each measured using the single photon initiated dissociative rearrangement reaction (SPIDRR) experimental technique. We believe that this is the first experimental study where such disparate dynamic features (SSR, TSR, and H-tunneling) are disentangled in a system's chemistry, attributing specific rate constant values to each effect and quantifying the various competitions. Moreover, multi-reference CASSCF/CASPT2 calculations indicate that structures with covalent Co-H bonds are present exclusively along the excited singlet surface. This phenomenon significantly reduces these structures' energy relative to their triplet counterparts, thus enabling the surface crossing and spin inversion that cause the observed two-state reactivity.
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Affiliation(s)
| | - Evan M Mastin
- Baylor University, 1311 S 5th St, Waco, TX 76706, USA.
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14
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Carter S, Tao W, Majumder R, Sokolov AY, Zhang S. Two-State Hydrogen Atom Transfer Reactivity of Unsymmetric [Cu 2(O)(NO)] 2+ Complexes. J Am Chem Soc 2023; 145:17779-17785. [PMID: 37540110 DOI: 10.1021/jacs.3c04510] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/05/2023]
Abstract
We report the temperature-dependent spin switching of dicopper oxo nitrosyl [Cu2(O)(NO)]2+ complexes and their influence on hydrogen atom transfer (HAT) reactivity. Electron paramagnetic resonance (EPR) and Evans method analysis suggest that [Cu2(O)(NO)]2+ complexes transition from the S = 1/2 to the S = 3/2 state around ca. 202 K. At low temperatures (198 K) where S = 3/2 dominates, a strong correlation between the rate of HAT (kHAT) and the population of the S = 1/2 state was identified (R2 = 0.988), suggesting that the HAT by [Cu2(O)(NO)]2+ complexes proceeds by the S = 1/2 isomer. Installation of functional groups that introduce an unsymmetric secondary coordination environment accelerates the HAT rates through perturbation of the spin equilibria. Given the often unsymmetric coordination sphere of bimetallic active sites in natural proteins, we anticipate that similar strategies could be employed by metalloenzymes to control HAT reactions.
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Affiliation(s)
- Samantha Carter
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Wenjie Tao
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Rajat Majumder
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Alexander Yu Sokolov
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Shiyu Zhang
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
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15
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Miao J, Song J, Lang J, Zhu Y, Dai J, Wei Y, Long M, Shao Z, Zhou B, Alvarez PJJ, Zhang L. Single-Atom MnN 5 Catalytic Sites Enable Efficient Peroxymonosulfate Activation by Forming Highly Reactive Mn(IV)-Oxo Species. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:4266-4275. [PMID: 36849443 DOI: 10.1021/acs.est.2c08836] [Citation(s) in RCA: 29] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Four-nitrogen-coordinated transitional metal (MN4) configurations in single-atom catalysts (SACs) are broadly recognized as the most efficient active sites in peroxymonosulfate (PMS)-based advanced oxidation processes. However, SACs with a coordination number higher than four are rarely explored, which represents a fundamental missed opportunity for coordination chemistry to boost PMS activation and degradation of recalcitrant organic pollutants. We experimentally and theoretically demonstrate here that five-nitrogen-coordinated Mn (MnN5) sites more effectively activate PMS than MnN4 sites, by facilitating the cleavage of the O-O bond into high-valent Mn(IV)-oxo species with nearly 100% selectivity. The high activity of MnN5 was discerned to be due to the formation of higher-spin-state N5Mn(IV)═O species, which enable efficient two-electron transfer from organics to Mn sites through a lower-energy-barrier pathway. Overall, this work demonstrates the importance of high coordination numbers in SACs for efficient PMS activation and informs the design of next-generation environmental catalysts.
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Affiliation(s)
- 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
| | - Jian Song
- 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, 393 Huaxia Middle Road, Shanghai 201210, China
| | - Yuan Zhu
- School of Chemistry and Chemical Engineering, Queen's University Belfast, Belfast BT7 1NN, U.K
| | - Jie Dai
- 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
| | - 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
| | - 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
| | - Zongping Shao
- WA School of Mines: Minerals, Energy and Chemical Engineering, Curtin University, Perth, Western Australia 6845, Australia
| | - Baoxue Zhou
- 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
| | - 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
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16
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Jana S, Pattanayak S, Das S, Ghosh M, Velasco L, Moonshiram D, Sen Gupta S. Comparing the reactivity of an oxoiron(IV) cation radical and its oxoiron(V) tautomer towards C-H bonds. Chem Commun (Camb) 2023; 59:2755-2758. [PMID: 36779358 DOI: 10.1039/d2cc07005g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
An oxoiron(IV) cation radical is generated upon two-electron oxidation of an iron(III) complex bearing an electron-rich methoxy substituted bTAML framework and thoroughly characterized via multiple spectroscopic techniques and density functional theory (DFT). Reactivity studies demonstrate faster rates for oxidation of strong aliphatic sp3 C-H bonds than for its corresponding oxoiron(V) valence tautomer.
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Affiliation(s)
- Sandipan Jana
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India.
| | - Santanu Pattanayak
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India.
| | - Soumadip Das
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India.
| | - Munmun Ghosh
- Department of Chemistry, Ashoka University, Rajiv Gandhi Education City, Sonepat, Haryana 131029, India.
| | - Lucia Velasco
- Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Sor Juana Inés de la Cruz, 3, 28049, Madrid, Spain.
| | - Dooshaye Moonshiram
- Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Sor Juana Inés de la Cruz, 3, 28049, Madrid, Spain.
| | - Sayam Sen Gupta
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India.
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17
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Mirzanejad A, Varganov SA. The role of the intermediate triplet state in iron-catalyzed multi-state C-H activation. Phys Chem Chem Phys 2022; 24:20721-20727. [PMID: 36018581 DOI: 10.1039/d2cp02733j] [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
Efficient activation and functionalization of the C-H bond under mild conditions are of a great interest in chemical synthesis. We investigate the previously proposed spin-accelerated activation of the C(sp2)-H bond by a Fe(II)-based catalyst to clarify the role of the intermediate triplet state in the reaction mechanism. High-level electronic structure calculations on a small model of a catalytic system utilizing the coupled cluster with the single, double, and perturbative triple excitations [CCSD(T)] are used to select the density functional for the full-size model. Our analysis indicates that the previously proposed two-state quintet-singlet reaction pathway is unlikely to be efficient due to a very weak spin-orbit coupling between these two spin states. We propose a more favorable multi-state quintet-triplet-singlet reaction pathway and discuss the importance of the intermediate triplet state. This triplet state facilitates a spin-accelerated reaction mechanism by strongly coupling to both quintet and singlet states. Our calculations show that the C-H bond activation through the proposed quintet-triplet-singlet reaction pathway is more thermodynamically favorable than the single-state quintet and two-state singlet-quintet mechanisms.
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Affiliation(s)
- Amir Mirzanejad
- Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia Street, Reno, NV 89557-0216, USA.
| | - Sergey A Varganov
- Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia Street, Reno, NV 89557-0216, USA.
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18
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Nandy A, Adamji H, Kastner DW, Vennelakanti V, Nazemi A, Liu M, Kulik HJ. Using Computational Chemistry To Reveal Nature’s Blueprints for Single-Site Catalysis of C–H Activation. ACS Catal 2022. [DOI: 10.1021/acscatal.2c02096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Aditya Nandy
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Husain Adamji
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - David W. Kastner
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Vyshnavi Vennelakanti
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Azadeh Nazemi
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Mingjie Liu
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Heather J. Kulik
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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19
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Gérard EF, Yadav V, Goldberg DP, de Visser SP. What Drives Radical Halogenation versus Hydroxylation in Mononuclear Nonheme Iron Complexes? A Combined Experimental and Computational Study. J Am Chem Soc 2022; 144:10752-10767. [PMID: 35537044 PMCID: PMC9228086 DOI: 10.1021/jacs.2c01375] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
![]()
Nonheme iron halogenases
are unique enzymes in nature that selectively
activate an aliphatic C–H bond of a substrate to convert it
into C–X (X = Cl/Br, but not F/I). It is proposed that they
generate an FeIII(OH)(X) intermediate in their catalytic
cycle. The analogous FeIII(OH) intermediate in nonheme
iron hydroxylases transfers OH• to give alcohol
product, whereas the halogenases transfer X• to
the carbon radical substrate. There remains significant debate regarding
what factors control their remarkable selectivity of the halogenases.
The reactivity of the complexes FeIII(BNPAPh2O)(OH)(X) (X = Cl, Br) with a secondary carbon radical (R•) is described. It is found that X• transfer occurs
with a secondary carbon radical, as opposed to OH• transfer with tertiary radicals. Comprehensive computational studies
involving density functional theory were carried out to examine the
possible origins of this selectivity. The calculations reproduce the
experimental findings, which indicate that halogen transfer is not
observed for the tertiary radicals because of a nonproductive equilibrium
that results from the endergonic nature of these reactions, despite
a potentially lower reaction barrier for the halogenation pathway.
In contrast, halogen transfer is favored for secondary carbon radicals,
for which the halogenated product complex is thermodynamically more
stable than the reactant complex. These results are rationalized by
considering the relative strengths of the C–X bonds that are
formed for tertiary versus secondary carbon centers. The computational
analysis also shows that the reaction barrier for halogen transfer
is significantly dependent on secondary coordination sphere effects,
including steric and H-bonding interactions.
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Affiliation(s)
- Emilie F Gérard
- Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom.,Department of Chemical Engineering, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Vishal Yadav
- 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
| | - Sam P de Visser
- Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom.,Department of Chemical Engineering, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
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20
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Vennelakanti V, Mehmood R, Kulik HJ. Are Vanadium Intermediates Suitable Mimics in Non-Heme Iron Enzymes? An Electronic Structure Analysis. ACS Catal 2022. [DOI: 10.1021/acscatal.2c01143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Vyshnavi Vennelakanti
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Rimsha Mehmood
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Heather J. Kulik
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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21
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Ali HS, de Visser SP. Electrostatic Perturbations in the Substrate-Binding Pocket of Taurine/α-Ketoglutarate Dioxygenase Determine its Selectivity. Chemistry 2022; 28:e202104167. [PMID: 34967481 PMCID: PMC9304159 DOI: 10.1002/chem.202104167] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Indexed: 11/17/2022]
Abstract
Taurine/α-ketoglutarate dioxygenase is an important enzyme that takes part in the cysteine catabolism process in the human body and selectively hydroxylates taurine at the C1 -position. Recent computational studies showed that in the gas-phase the C2 -H bond of taurine is substantially weaker than the C1 -H bond, yet no evidence exists of 2-hydroxytaurine products. To this end, a detailed computational study on the selectivity patterns in TauD was performed. The calculations show that the second-coordination sphere and the protonation states of residues play a major role in guiding the enzyme to the right selectivity. Specifically, a single proton on an active site histidine residue can change the regioselectivity of the reaction through its electrostatic perturbations in the active site and effectively changes the C1 -H and C2 -H bond strengths of taurine. This is further emphasized by many polar and hydrogen bonding interactions of the protein cage in TauD with the substrate and the oxidant that weaken the pro-R C1 -H bond and triggers a chemoselective reaction process. The large cluster models reproduce the experimental free energy of activation excellently.
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Affiliation(s)
- Hafiz Saqib Ali
- Manchester Institute of BiotechnologyThe University of Manchester131 Princess StreetManchesterM1 7DNUK
- Department of ChemistryThe University of ManchesterOxford RoadManchesterM13 9PLUK
| | - Sam P. de Visser
- Manchester Institute of BiotechnologyThe University of Manchester131 Princess StreetManchesterM1 7DNUK
- Department of Chemical Engineering and Analytical ScienceThe University of ManchesterOxford RoadManchesterM13 9PLUK
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22
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Lewis TWR, Mastin EM, Theis ZC, Gutierrez MG, Bellert DJ. Measurement of time dependent product branching ratios indicates two-state reactivity in metal mediated chemical reactions. Phys Chem Chem Phys 2022; 24:2300-2308. [PMID: 35015007 DOI: 10.1039/d1cp05473b] [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
For several decades, the influence of Two State Reactivity (TSR) has been implicated in a host of reactions, but has lacked a stand-alone, definitive experimental kinetic signature identifying its occurrence. Here, we demonstrate that the measurement of a temporally dependent product branching ratio is indicative of spin inversion and is a kinetic signature of TSR. This is caused by products exiting different hypersurfaces with different rates and relative exothermicities. The composite measurement of product intensities with the same mass but with different multiplicities yield biexponential temporal dependences with the sampled product ratio changing in time. These measurements are made using the single photon initiated dissociative rearrangement reaction (SPIDRR) technique which identifies TSR but further determines the kinetic parameters for reaction along the original ground electronic surface in competition with spin inversion and its consequent TSR.
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Affiliation(s)
- Tucker W R Lewis
- Department of Chemistry and Biochemistry, Baylor University, Darrin Bellert, One Bear Place #97348, Waco, TX 76798, USA
| | - Evan M Mastin
- Department of Chemistry and Biochemistry, Baylor University, Darrin Bellert, One Bear Place #97348, Waco, TX 76798, USA
| | - Zachry C Theis
- Department of Chemistry and Biochemistry, Baylor University, Darrin Bellert, One Bear Place #97348, Waco, TX 76798, USA
| | - Michael G Gutierrez
- Department of Chemistry and Biochemistry, Baylor University, Darrin Bellert, One Bear Place #97348, Waco, TX 76798, USA
| | - Darrin J Bellert
- Department of Chemistry and Biochemistry, Baylor University, Darrin Bellert, One Bear Place #97348, Waco, TX 76798, USA
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23
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Li R, Yang X, Ping H. A radical mechanism for C–H bond cross-coupling and N 2 activation catalysed by β-diketiminate iron complexes. Catal Sci Technol 2022. [DOI: 10.1039/d2cy00564f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Density functional theory calculations and electronic structure analyses reveal a radical mechanism with spin-crossovers for C–H bond cross-coupling and N2 activation catalysed by β-diketiminate iron complexes.
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Affiliation(s)
- Rongrong Li
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Xinzheng Yang
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
- Department of Chemistry, University of Washington, Seattle, WA 98195, USA
| | - Hongming Ping
- Department of Computer Science, University of Nottingham Ningbo China, Ningbo, 315100, China
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24
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Metabolism of 8-aminoquinoline (8AQ) primaquine via aromatic hydroxylation step mediated by cytochrome P450 enzyme using density functional theory. J Organomet Chem 2022. [DOI: 10.1016/j.jorganchem.2021.122154] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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25
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Wong HPH, Mokkawes T, de Visser SP. Can the isonitrile biosynthesis enzyme ScoE assist with the biosynthesis of isonitrile groups in drug molecules? A computational study. Phys Chem Chem Phys 2022; 24:27250-27262. [DOI: 10.1039/d2cp03409c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Computational studies show that the isonitrile synthesizing enzyme ScoE can catalyse the conversion of γ-Gly substituents in substrates to isonitrile. This enables efficient isonitrile substitution into target molecules such as axisonitrile-1.
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Affiliation(s)
- Henrik P. H. Wong
- Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK
- Department of Chemical Engineering, Oxford Road, Manchester M13 9PL, UK
| | - Thirakorn Mokkawes
- Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK
- Department of Chemical Engineering, Oxford Road, Manchester M13 9PL, UK
| | - Sam P. de Visser
- Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK
- Department of Chemical Engineering, Oxford Road, Manchester M13 9PL, UK
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26
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Truong PT, Miller SG, McLaughlin Sta Maria EJ, Bowring MA. Large Isotope Effects in Organometallic Chemistry. Chemistry 2021; 27:14800-14815. [PMID: 34347912 DOI: 10.1002/chem.202102189] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Indexed: 01/24/2023]
Abstract
The kinetic isotope effect (KIE) is key to understanding reaction mechanisms in many areas of chemistry and chemical biology, including organometallic chemistry. This ratio of rate constants, kH /kD , typically falls between 1-7. However, KIEs up to 105 have been reported, and can even be so large that reactivity with deuterium is unobserved. We collect here examples of large KIEs across organometallic chemistry, in catalytic and stoichiometric reactions, along with their mechanistic interpretations. Large KIEs occur in proton transfer reactions such as protonation of organometallic complexes and clusters, protonolysis of metal-carbon bonds, and dihydrogen reactivity. C-H activation reactions with large KIEs occur with late and early transition metals, photogenerated intermediates, and abstraction by metal-oxo complexes. We categorize the mechanistic interpretations of large KIEs into the following three types: (a) proton tunneling, (b) compound effects from multiple steps, and (c) semi-classical effects on a single step. This comprehensive collection of large KIEs in organometallics provides context for future mechanistic interpretation.
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Affiliation(s)
- Phan T Truong
- Department of Chemistry, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97222
| | - Sophia G Miller
- Department of Chemistry, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97222
| | | | - Miriam A Bowring
- Department of Chemistry, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97222
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27
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Awasthi N, Yadav R, Shukla A, Kumar D. Interplay between two degenerate spin state determines the hydroxylation of 4-nitrophenol catalyzed via Cytochrome P450. INORG CHEM COMMUN 2021. [DOI: 10.1016/j.inoche.2021.108857] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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28
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Yeh CCG, Pierides C, Jameson GNL, de Visser SP. Structure and Functional Differences of Cysteine and 3-Mercaptopropionate Dioxygenases: A Computational Study. Chemistry 2021; 27:13793-13806. [PMID: 34310770 DOI: 10.1002/chem.202101878] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Indexed: 11/09/2022]
Abstract
Thiol dioxygenases are important enzymes for human health; they are involved in the detoxification and catabolism of toxic thiol-containing natural products such as cysteine. As such, these enzymes have relevance to the development of Alzheimer's and Parkinson's diseases in the brain. Recent crystal structure coordinates of cysteine and 3-mercaptopropionate dioxygenase (CDO and MDO) showed major differences in the second-coordination spheres of the two enzymes. To understand the difference in activity between these two analogous enzymes, we created large, active-site cluster models. We show that CDO and MDO have different iron(III)-superoxo-bound structures due to differences in ligand coordination. Furthermore, our studies show that the differences in the second-coordination sphere and particularly the position of a positively charged Arg residue results in changes in substrate positioning, mobility and enzymatic turnover. Furthermore, the substrate scope of MDO is explored with cysteinate and 2-mercaptosuccinic acid and their reactivity is predicted.
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Affiliation(s)
- C-C George Yeh
- Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.,Department of Chemical Engineering and Analytical Science, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Christos Pierides
- Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.,Department of Chemical Engineering and Analytical Science, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Guy N L Jameson
- School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, 30 Flemington Road, Parkville, Vic, 3010, Australia
| | - Sam P de Visser
- Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.,Department of Chemical Engineering and Analytical Science, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK
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29
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Vennelakanti V, Nandy A, Kulik HJ. The Effect of Hartree-Fock Exchange on Scaling Relations and Reaction Energetics for C–H Activation Catalysts. Top Catal 2021. [DOI: 10.1007/s11244-021-01482-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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30
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Latifi R, Palluccio TD, Ye W, Minnick JL, Glinton KS, Rybak-Akimova EV, de Visser SP, Tahsini L. pH Changes That Induce an Axial Ligand Effect on Nonheme Iron(IV) Oxo Complexes with an Appended Aminopropyl Functionality. Inorg Chem 2021; 60:13821-13832. [PMID: 34291939 DOI: 10.1021/acs.inorgchem.1c01312] [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
Nonheme iron enzymes often utilize a high-valent iron(IV) oxo species for the biosynthesis of natural products, but their high reactivity often precludes structural and functional studies of these complexes. In this work, a combined experimental and computational study is presented on a biomimetic nonheme iron(IV) oxo complex bearing an aminopyridine macrocyclic ligand and its reactivity toward olefin epoxidation upon changes in the identity and coordination ability of the axial ligand. Herein, we show a dramatic effect of the pH on the oxygen-atom-transfer (OAT) reaction with substrates. In particular, these changes have occurred because of protonation of the axial-bound pendant amine group, where its coordination to iron is replaced by a solvent molecule or anionic ligand. This axial ligand effect influences the catalysis, and we observe enhanced cyclooctene epoxidation yields and turnover numbers in the presence of the unbound protonated pendant amine group. Density functional theory studies were performed to support the experiments and highlight that replacement of the pendant amine with a neutral or anionic ligand dramatically lowers the rate-determining barriers of cyclooctene epoxidation. The computational work further establishes that the change in OAT is due to electrostatic interactions of the pendant amine cation that favorably affect the barrier heights.
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Affiliation(s)
- Reza Latifi
- Department of Chemistry, Oklahoma State University, Stillwater, Oklahoma 74078, United States
| | - Taryn D Palluccio
- Department of Chemistry, Tufts University, Medford, Massachusetts 02155, United States
| | - Wanhua Ye
- Department of Chemistry, Tufts University, Medford, Massachusetts 02155, United States
| | - Jennifer L Minnick
- Department of Chemistry, Oklahoma State University, Stillwater, Oklahoma 74078, United States
| | - Kwame S Glinton
- Department of Chemistry, Oklahoma State University, Stillwater, Oklahoma 74078, United States
| | - Elena V Rybak-Akimova
- Department of Chemistry, Tufts University, Medford, Massachusetts 02155, United States
| | - Sam P de Visser
- Manchester Institute of Biotechnology and Department of Chemical Engineering and Analytical Science, The University of Manchester, Manchester M1 7DN, United Kingdom
| | - Laleh Tahsini
- Department of Chemistry, Oklahoma State University, Stillwater, Oklahoma 74078, United States
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31
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Mukherjee G, Satpathy JK, Bagha UK, Mubarak MQE, Sastri CV, de Visser SP. Inspiration from Nature: Influence of Engineered Ligand Scaffolds and Auxiliary Factors on the Reactivity of Biomimetic Oxidants. ACS Catal 2021. [DOI: 10.1021/acscatal.1c01993] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Gourab Mukherjee
- Department of Chemistry, Indian Institute of Technology Guwahati, 781039, Assam, India
| | - Jagnyesh K. Satpathy
- Department of Chemistry, Indian Institute of Technology Guwahati, 781039, Assam, India
| | - Umesh K. Bagha
- Department of Chemistry, Indian Institute of Technology Guwahati, 781039, Assam, India
| | - M. Qadri E. Mubarak
- Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
- Fakulti Sains dan Teknologi, Universiti Sains Islam Malaysia, Bandar Baru Nilai, 71800 Nilai, Negeri Sembilan Malaysia
| | - Chivukula V. Sastri
- Department of Chemistry, Indian Institute of Technology Guwahati, 781039, Assam, India
| | - Sam P. de Visser
- Department of Chemistry, Indian Institute of Technology Guwahati, 781039, Assam, India
- Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
- Department of Chemical Engineering and Analytical Science, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
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32
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Singh W, Hui C, Li C, Huang M. Thebaine is Selectively Demethylated by Thebaine 6- O-Demethylase and Codeine-3- O-demethylase at Distinct Binding Sites: A Computational Study. Inorg Chem 2021; 60:10199-10214. [PMID: 34213893 DOI: 10.1021/acs.inorgchem.1c00468] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Two homologous 2-oxoglutarate-dependent (ODD) nonheme enzymes thebaine 6-O-demethylase (T6ODM) and codeine-3-O-demethylase (CODM), are involved in the morphine biosynthesis pathway from thebaine, catalyzing the O-demethylation reaction with precise regioselectivity at C6 and C3 positions of thebaine respectively. We investigated the origin of the regioselectivity of these enzymes by combined molecular dynamics (MD) and quantum mechanics/molecular mechanics (QM/MM) calculations and found that Thebaine binds at the two distinct sites of T6ODM and CODM, which determines the regioselectivity of the enzymes. A remarkable oxo rotation is observed in the decarboxylation process. Starting from the closed pentacoordinate configuration, the C-terminal lid adopts an open conformation in the octahedral Fe(IV) = O complex to facilitate the subsequent demethylation. Phe241 and Phe311 stabilize the substrate in the binding pocket, while Arg219 acts as a gatekeeper residue to stabilize the substrate. Our results unravel the regioselectivity in 2-OG dependent nonheme enzymes and may shed light for exploring the substrate scope of these enzymes and developing novel biotechnology for morphine biosynthesis.
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Affiliation(s)
- Warispreet Singh
- Department of Chemistry & Chemical Engineering, Queen's University, Belfast BT9 5AG, United Kingdom
| | - Chenggong Hui
- Department of Chemistry & Chemical Engineering, Queen's University, Belfast BT9 5AG, United Kingdom
| | - Chun Li
- Key Lab of Industrial Biocatalysis Ministry of Education, Institute of Biochemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, P. R. China
| | - Meilan Huang
- Department of Chemistry & Chemical Engineering, Queen's University, Belfast BT9 5AG, United Kingdom
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33
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Density Functional Theory Study into the Reaction Mechanism of Isonitrile Biosynthesis by the Nonheme Iron Enzyme ScoE. Top Catal 2021. [DOI: 10.1007/s11244-021-01460-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
AbstractThe nonheme iron enzyme ScoE catalyzes the biosynthesis of an isonitrile substituent in a peptide chain. To understand details of the reaction mechanism we created a large active site cluster model of 212 atoms that contains substrate, the active oxidant and the first- and second-coordination sphere of the protein and solvent. Several possible reaction mechanisms were tested and it is shown that isonitrile can only be formed through two consecutive catalytic cycles that both use one molecule of dioxygen and α-ketoglutarate. In both cycles the active species is an iron(IV)-oxo species that in the first reaction cycle reacts through two consecutive hydrogen atom abstraction steps: first from the N–H group and thereafter from the C–H group to desaturate the NH-CH2 bond. The alternative ordering of hydrogen atom abstraction steps was also tested but found to be higher in energy. Moreover, the electronic configurations along that pathway implicate an initial hydride transfer followed by proton transfer. We highlight an active site Lys residue that is shown to donate charge in the transition states and influences the relative barrier heights and bifurcation pathways. A second catalytic cycle of the reaction of iron(IV)-oxo with desaturated substrate starts with hydrogen atom abstraction followed by decarboxylation to give isonitrile directly. The catalytic cycle is completed with a proton transfer to iron(II)-hydroxo to generate the iron(II)-water resting state. The work is compared with experimental observation and previous computational studies on this system and put in a larger perspective of nonheme iron chemistry.
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34
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Warm K, Monte Pérez I, Kuhlmann U, Hildebrandt P, Farquhar E, Swart M, Ray K. Stable, but still reactive – investigations on the effects of Lewis acid binding on copper nitrene intermediates. Z Anorg Allg Chem 2021. [DOI: 10.1002/zaac.202100092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Katrin Warm
- Institut für Chemie Humboldt-Universität zu Berlin Brook-Taylor-Straße 2 12489 Berlin Germany
| | - Inés Monte Pérez
- Institut für Chemie Humboldt-Universität zu Berlin Brook-Taylor-Straße 2 12489 Berlin Germany
| | - Uwe Kuhlmann
- Institut für Chemie Technische Universität Berlin Fakultät II Straße des 17. Juni 135 10623 Berlin Germany
| | - Peter Hildebrandt
- Institut für Chemie Technische Universität Berlin Fakultät II Straße des 17. Juni 135 10623 Berlin Germany
| | - Erik Farquhar
- Brookhaven National Laboratory NSLS-II, Bldg. 745, Room 106, P.O. Box 5000 11973-5000 Upton NY United States
| | - Marcel Swart
- Institut de Química Computacional i Catàlisi Universitat de Girona Campus Montilivi (Ciències) Maria Aurèlia Capmany i Farnés, 69 17003 Girona, ICREA and Pg. Lluís Companys 23 08010 Barcelona Spain
| | - Kallol Ray
- Institut für Chemie Humboldt-Universität zu Berlin Brook-Taylor-Straße 2 12489 Berlin Germany
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35
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Ali HS, Henchman RH, Visser SP. Mechanism of Oxidative Ring‐Closure as Part of the Hygromycin Biosynthesis Step by a Nonheme Iron Dioxygenase. ChemCatChem 2021. [DOI: 10.1002/cctc.202100393] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Hafiz Saqib Ali
- Manchester Institute of Biotechnology The University of Manchester 131 Princess Street Manchester M1 7DN UK
- Department of Chemistry The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Richard H. Henchman
- Manchester Institute of Biotechnology The University of Manchester 131 Princess Street Manchester M1 7DN UK
- Department of Chemistry The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Sam P. Visser
- Manchester Institute of Biotechnology The University of Manchester 131 Princess Street Manchester M1 7DN UK
- Department of Chemical Engineering and Analytical Science The University of Manchester Oxford Road Manchester M13 9PL UK
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36
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Jeong D, Hirao H, Cho J. Theoretical Study on the Aliphatic
C─H
Bond Activation by a Mononuclear Manganese(
III
) Iodosylbenzene Complex. B KOREAN CHEM SOC 2021. [DOI: 10.1002/bkcs.12300] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Donghyun Jeong
- Department of Chemistry Ulsan National Institute of Science and Technology (UNIST) Ulsan 44919 Korea
- Department of Emerging Materials Science DGIST Daegu 42988 Korea
| | - Hajime Hirao
- Warshel Institute for Computational Biology School of Life and Health Sciences, The Chinese University of Hong Kong Shenzhen, Longgang District, Shenzhen 518172 China
| | - Jaeheung Cho
- Department of Chemistry Ulsan National Institute of Science and Technology (UNIST) Ulsan 44919 Korea
- Department of Emerging Materials Science DGIST Daegu 42988 Korea
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37
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Liu J, Wu P, Yan S, Li Y, Cao Z, Wang B. Spin-Regulated Inner-Sphere Electron Transfer Enables Efficient O—O Bond Activation in Nonheme Diiron Monooxygenase MIOX. ACS Catal 2021. [DOI: 10.1021/acscatal.1c00898] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Jia Liu
- State Key Laboratory of Structural Chemistry of Solid Surface and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Peng Wu
- State Key Laboratory of Structural Chemistry of Solid Surface and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Shengheng Yan
- State Key Laboratory of Structural Chemistry of Solid Surface and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Yuanyuan Li
- College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, China
| | - Zexing Cao
- State Key Laboratory of Structural Chemistry of Solid Surface and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Binju Wang
- State Key Laboratory of Structural Chemistry of Solid Surface and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
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38
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Ali HS, Henchman RH, Warwicker J, de Visser SP. How Do Electrostatic Perturbations of the Protein Affect the Bifurcation Pathways of Substrate Hydroxylation versus Desaturation in the Nonheme Iron-Dependent Viomycin Biosynthesis Enzyme? J Phys Chem A 2021; 125:1720-1737. [DOI: 10.1021/acs.jpca.1c00141] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Hafiz Saqib Ali
- Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Richard H. Henchman
- Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Jim Warwicker
- Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Sam P. de Visser
- Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
- Department of Chemical Engineering and Analytical Science, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K
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39
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Zima AM, Lyakin OY, Bushmin DS, Soshnikov IE, Bryliakov KP, Talsi EP. Non-heme perferryl intermediates: Effect of spin state on the epoxidation enantioselectivity. MOLECULAR CATALYSIS 2021. [DOI: 10.1016/j.mcat.2021.111403] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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40
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Tavani F, Capocasa G, Martini A, Sessa F, Di Stefano S, Lanzalunga O, D'Angelo P. Activation of C-H bonds by a nonheme iron(IV)-oxo complex: mechanistic evidence through a coupled EDXAS/UV-Vis multivariate analysis. Phys Chem Chem Phys 2021; 23:1188-1196. [PMID: 33355324 DOI: 10.1039/d0cp04304d] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The understanding of reactive processes involving organic substrates is crucial to chemical knowledge and requires multidisciplinary efforts for its advancement. Herein, we apply a combined multivariate, statistical and theoretical analysis of coupled time-resolved X-ray absorption (XAS)/UV-Vis data to obtain detailed mechanistic information for on the C-H bond activation of 9,10-dihydroanthracene (DHA) and diphenylmethane (Ph2CH2) by the nonheme FeIV-oxo complex [N4Py·FeIV(O)]2+ (N4Py = N,N-bis(2-pyridylmethyl)-N-bis(2-pyridyl)methylamine) in CH3CN at room temperature. Within this approach, we determine the number of key chemical species present in the reaction mixtures and derive spectral and concentration profiles for the reaction intermediates. From the quantitative analysis of the XAS spectra the transient intermediate species are structurally determined. As a result, it is suggested that, while DHA is oxidized by [N4Py·FeIV(O)]2+ with a hydrogen atom transfer-electron transfer (HAT-ET) mechanism, Ph2CH2 is oxidized by the nonheme iron-oxo complex through a HAT-radical dissociation pathway. In the latter process, we prove that the intermediate FeIII complex [N4Py·FeIII(OH)]2+ is not able to oxidize the diphenylmethyl radical and we provide its structural characterization in solution. The employed combined experimental and theoretical strategy is promising for the spectroscopic characterization of transient intermediates as well as for the mechanistic investigation of redox chemical transformations on the second to millisecond time scales.
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Affiliation(s)
- Francesco Tavani
- Dipartimento di Chimica, Università di Roma "La Sapienza", P.le A. Moro 5, 00185 Roma, Italy.
| | - Giorgio Capocasa
- Dipartimento di Chimica, Università di Roma "La Sapienza", P.le A. Moro 5, 00185 Roma, Italy.
| | - Andrea Martini
- Dipartimento di Chimica, Università degli Studi di Torino, Via P. Giuria 7, 10125 Torino, Italy and The Smart Materials Research Institute, Southern Federal University, 344090 Sladkova 178/24 Rostov-on-Don, Russia
| | - Francesco Sessa
- Dipartimento di Chimica, Università di Roma "La Sapienza", P.le A. Moro 5, 00185 Roma, Italy.
| | - Stefano Di Stefano
- Dipartimento di Chimica, Università di Roma "La Sapienza", P.le A. Moro 5, 00185 Roma, Italy.
| | - Osvaldo Lanzalunga
- Dipartimento di Chimica, Università di Roma "La Sapienza", P.le A. Moro 5, 00185 Roma, Italy.
| | - Paola D'Angelo
- Dipartimento di Chimica, Università di Roma "La Sapienza", P.le A. Moro 5, 00185 Roma, Italy.
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41
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Lin J, Sun Q, Sun W. A DFT study on the C-H oxidation reactivity of Fe(iv)-oxo species with N4/N5 ligands derived from l-proline. RSC Adv 2021; 11:2293-2297. [PMID: 35424189 PMCID: PMC8693871 DOI: 10.1039/d0ra08496d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 12/08/2020] [Indexed: 11/26/2022] Open
Abstract
The hydroxylation of hexane by two FeIVO complexes bearing a pentadentate ligand (N5, Pro3Py) and a tetradentate ligand (N4, Pro2PyBn) derived from l-proline was studied by DFT calculations. Theoretical results predict that both FeIVO complexes hold triplet ground states. The hydrogen atom abstraction (HAA) processes by both FeIVO species proceed through a two-state reactivity, thus indicating that HAA occurs via a low-barrier quintet surface. Beyond the conventional rebound step, the dissociation path is also calculated and is found to potentially occur after HAA.
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Affiliation(s)
- Jin Lin
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, Center for Excellence in Molecular Synthesis, Suzhou Research Institute of LICP, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences Lanzhou 730000 P. R. China
- University of Chinese Academy of Sciences Beijing 100049 P. R. China
| | - Qiangsheng Sun
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, Center for Excellence in Molecular Synthesis, Suzhou Research Institute of LICP, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences Lanzhou 730000 P. R. China
| | - Wei Sun
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, Center for Excellence in Molecular Synthesis, Suzhou Research Institute of LICP, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences Lanzhou 730000 P. R. China
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42
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Miyagawa K, Isobe H, Shoji M, Kawakami T, Yamanaka S, Yamaguchi K. A three states model for hydrogen abstraction reactions with the cytochrome P450 compound I is revisited. Isolobal and isospin analogy among Fe(IV)=O, O = O and O. J Photochem Photobiol A Chem 2021. [DOI: 10.1016/j.jphotochem.2020.112902] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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43
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Liu N, Chen X, Jin L, Yang YF, She YB. A mechanistic study of the manganese porphyrin-catalyzed C–H isocyanation reaction. Org Chem Front 2021. [DOI: 10.1039/d0qo01442g] [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
The favourable radical rebound pathway is NCO-rebound from the Mn(TMP)(NCO)2 complex due to the stronger trans effect of the axial ligand NCO and the electron-donating aryl substituents on the porphyrin ligand.
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Affiliation(s)
- Ning Liu
- College of Chemical Engineering
- Zhejiang University of Technology
- Hangzhou
- China
| | - Xiahe Chen
- College of Chemical Engineering
- Zhejiang University of Technology
- Hangzhou
- China
| | - Liyuan Jin
- College of Chemical Engineering
- Zhejiang University of Technology
- Hangzhou
- China
| | - Yun-Fang Yang
- College of Chemical Engineering
- Zhejiang University of Technology
- Hangzhou
- China
| | - Yuan-Bin She
- College of Chemical Engineering
- Zhejiang University of Technology
- Hangzhou
- China
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44
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Yamaguchi K, Miyagawa K, Isobe H, Shoji M, Kawakami T, Yamanaka S. Isolobal and isospin analogy between organic and inorganic open-shell molecules—Application to oxygenation reactions by active oxygen and oxy-radicals and water oxidation in the native and artificial photosynthesis. ADVANCES IN QUANTUM CHEMISTRY 2021. [DOI: 10.1016/bs.aiq.2021.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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45
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Nandy A, Kulik HJ. Why Conventional Design Rules for C–H Activation Fail for Open-Shell Transition-Metal Catalysts. ACS Catal 2020. [DOI: 10.1021/acscatal.0c04300] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Aditya Nandy
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Heather J. Kulik
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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46
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Latifi R, Minnick JL, Quesne MG, de Visser SP, Tahsini L. Computational studies of DNA base repair mechanisms by nonheme iron dioxygenases: selective epoxidation and hydroxylation pathways. Dalton Trans 2020; 49:4266-4276. [PMID: 32141456 DOI: 10.1039/d0dt00007h] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
DNA base repair mechanisms of alkylated DNA bases is an important reaction in chemical biology and particularly in the human body. It is typically catalyzed by an α-ketoglutarate-dependent nonheme iron dioxygenase named the AlkB repair enzyme. In this work we report a detailed computational study into the structure and reactivity of AlkB repair enzymes with alkylated DNA bases. In particular, we investigate the aliphatic hydroxylation and C[double bond, length as m-dash]C epoxidation mechanisms of alkylated DNA bases by a high-valent iron(iv)-oxo intermediate. Our computational studies use quantum mechanics/molecular mechanics methods on full enzymatic structures as well as cluster models on active site systems. The work shows that the iron(iv)-oxo species is rapidly formed after dioxygen binding to an iron(ii) center and passes a bicyclic ring structure as intermediate. Subsequent cluster models explore the mechanism of substrate hydroxylation and epoxidation of alkylated DNA bases. The work shows low energy barriers for substrate activation and consequently energetically feasible pathways are predicted. Overall, the work shows that a high-valent iron(iv)-oxo species can efficiently dealkylate alkylated DNA bases and return them into their original form.
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Affiliation(s)
- Reza Latifi
- Department of Chemistry, Oklahoma State University, 107 Physical Science Building, Stillwater, Oklahoma 74078, USA.
| | - Jennifer L Minnick
- Department of Chemistry, Oklahoma State University, 107 Physical Science Building, Stillwater, Oklahoma 74078, USA.
| | - Matthew G Quesne
- Cardiff University, School of Chemistry, Main Building, Park Place, Cardiff, CF10 3AT, UK. and Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxon, OX110FA, UK
| | - Sam P de Visser
- Manchester Institute of Biotechnology and Department of Chemical Engineering and Analytical Science, 131 Princess Street, Manchester M1 7DN, UK.
| | - Laleh Tahsini
- Department of Chemistry, Oklahoma State University, 107 Physical Science Building, Stillwater, Oklahoma 74078, USA.
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47
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Zhao L, Watanabe KJ, Nakatani N, Nakayama A, Xu X, Hasegawa JY. Extending nudged elastic band method to reaction pathways involving multiple spin states. J Chem Phys 2020; 153:134114. [PMID: 33032404 DOI: 10.1063/5.0021923] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
There are diverse reactions including spin-state crossing, especially the reactions catalyzed by transition metal compounds. To figure out the mechanisms of such reactions, the discussion of minimum energy intersystem crossing (MEISC) points cannot be avoided. These points may be the bottleneck of the reaction or inversely accelerate the reactions by providing a better pathway. It is of great importance to reveal their role in the reactions by computationally locating the position of the MEISC points together with the reaction pathway. However, providing a proper initial guess for the structure of the MEISC point is not as easy as that of the transition state. In this work, we extended the nudged elastic band (NEB) method for multiple spin systems, which is named the multiple spin-state NEB method, and it is successfully applied to find the MEISC points while optimizing the reaction pathway. For more precisely locating the MEISC point, a revised approach was adopted. Meanwhile, our examples also suggest that special attention should be paid to the criterion to define an image optimized as the MEISC point.
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Affiliation(s)
- Liming Zhao
- Institute for Catalysis, Hokkaido University, N21 W10 Kita-ku, Sapporo 001-0021, Hokkaido, Japan
| | - K-Jiro Watanabe
- Institute for Catalysis, Hokkaido University, N21 W10 Kita-ku, Sapporo 001-0021, Hokkaido, Japan
| | - Naoki Nakatani
- Graduate School of Science and Engineering, Tokyo Metropolitan University, Minami-Osawa 1-1, Tokyo 192-0397, Japan
| | - Akira Nakayama
- Department of Chemical System Engineering, The University of Tokyo, Tokyo 113-8656, Japan
| | - Xin Xu
- Department of Chemistry, Fudan University, Shanghai 200433, China
| | - Jun-Ya Hasegawa
- Institute for Catalysis, Hokkaido University, N21 W10 Kita-ku, Sapporo 001-0021, Hokkaido, Japan
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Saito K, Watabe Y, Miyazaki T, Takayanagi T, Hasegawa JY. Spin-inversion mechanisms in O 2 binding to a model heme compound: A perspective from nonadiabatic wave packet calculations. J Comput Chem 2020; 41:2527-2537. [PMID: 32841410 DOI: 10.1002/jcc.26409] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 07/18/2020] [Accepted: 08/08/2020] [Indexed: 12/13/2022]
Abstract
Spin-inversion dynamics in O2 binding to a model heme complex, which consisted of Fe(II)-porphyrin and imidazole, were studied using nonadiabatic wave packet dynamics calculations. We considered three active nuclear degrees of freedom in the dynamics, including the motions along the Fe-O distance, Fe-O-O angle, and Fe out-of-plane distance. Spin-free potential energy surfaces for the singlet, triplet, quintet, and septet states were developed using density functional theory calculations, and spin-orbit coupling elements were obtained from CASSCF-level electronic structure calculations. The spin-inversion mainly occurred between the singlet state and one of the triplet states due to large spin-orbit couplings and the contributions of other states were extremely small. The present quantum dynamics calculations suggested that the narrow crossing region model plays a dominant role in the O2 binding dynamics. In addition, the one-dimensional Landau-Zener model underestimated the nonadiabatic transition probability.
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Affiliation(s)
- Kohei Saito
- Department of Chemistry, Saitama University, Saitama City, Saitama, Japan
| | - Yuya Watabe
- Department of Chemistry, Saitama University, Saitama City, Saitama, Japan
| | - Takaaki Miyazaki
- Department of Chemistry, Saitama University, Saitama City, Saitama, Japan
| | | | - Jun-Ya Hasegawa
- Institute for Catalysis, Hokkaido University, Sapporo, Hokkaido, Japan
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Yeh CG, Hörner G, Visser SP. Computational Study on O–O Bond Formation on a Mononuclear Non‐Heme Iron Center. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000321] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Chieh‐Chih George Yeh
- Manchester Institute of Biotechnology and Department of Chemical Engineering and Analytical Science The University of Manchester 131 Princess Street M1 7DN Manchester UK
| | - Gerald Hörner
- Institut für Anorganische Chemie IV / NW I Universität Bayreuth Universitätsstraße 30 95440 Bayreuth Germany
| | - Sam P. Visser
- Manchester Institute of Biotechnology and Department of Chemical Engineering and Analytical Science The University of Manchester 131 Princess Street M1 7DN Manchester UK
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Larson VA, Battistella B, Ray K, Lehnert N, Nam W. Iron and manganese oxo complexes, oxo wall and beyond. Nat Rev Chem 2020; 4:404-419. [PMID: 37127969 DOI: 10.1038/s41570-020-0197-9] [Citation(s) in RCA: 139] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/15/2020] [Indexed: 11/09/2022]
Abstract
High-valent metal-oxo species with multiply-bonded M-O groups have been proposed as key intermediates in many biological and abiological catalytic oxidation reactions. These intermediates are implicated as active oxidants in alkane hydroxylation, olefin epoxidation and other oxidation reactions. For example, [FeivO(porphyrinato•-)]+ cofactors bearing π-radical porphyrinato•- ligands oxidize organic substrates in cytochrome P450 enzymes, which are common to many life forms. Likewise, high-valent Mn-oxo species are active for H2O oxidation in photosystem II. The chemistry of these native reactive species has inspired chemists to prepare highly oxidized transition-metal complexes as functional mimics. Although many synthetic Fe-O and Mn-O complexes now exist, the analogous oxo complexes of the late transition metals (groups 9-11) are rare. Indeed, late-transition-metal-oxo complexes of tetragonal (fourfold) symmetry should be electronically unstable, a rule commonly referred to as the 'oxo wall'. A few late metal-oxos have been prepared by targeting other symmetries or unusual spin states. These complexes have been studied using spectroscopic and theoretical methods. This Review describes mononuclear non-haem Fe-O and Mn-O species, the nature of the oxo wall and recent advances in the preparation of oxo complexes of Co, Ni and Cu beyond the oxo wall.
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