1
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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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2
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Su Y, Lai W. Unraveling the Mechanism of the Oxidative C-C Bond Coupling Reaction Catalyzed by Deoxypodophyllotoxin Synthase. Inorg Chem 2024; 63:13948-13958. [PMID: 39008659 DOI: 10.1021/acs.inorgchem.4c01263] [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: 07/17/2024]
Abstract
Deoxypodophyllotoxin synthase (DPS), a nonheme Fe(II)/2-oxoglutarate (2OG)-dependent oxygenase, is a key enzyme that is involved in the construction of the fused-ring system in (-)-podophyllotoxin biosynthesis by catalyzing the C-C coupling reaction. However, the mechanistic details of DPS-catalyzed ring formation remain unclear. Herein, our quantum mechanics/molecular mechanics (QM/MM) calculations reveal a novel mechanism that involves the recycling of CO2 (a product of decarboxylation of 2OG) to prevent the formation of hydroxylated byproducts. Our results show that CO2 can react with the FeIII-OH species to generate an unusual FeIII-bicarbonate species. In this way, hydroxylation is avoided by consuming the OH group. Then, the C-C coupling followed by desaturation yields the final product, deoxypodophyllotoxin. This work highlights the crucial role of the CO2 molecule, generated in the crevice between the iron active site and the substrate, in controlling the reaction selectivity.
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Affiliation(s)
- Yanzhuang Su
- Key Laboratory of Advanced Light Conversion Materials and Biophotonics, School of Chemistry and Life Resources, Renmin University of China, Beijing 100872, China
| | - Wenzhen Lai
- Key Laboratory of Advanced Light Conversion Materials and Biophotonics, School of Chemistry and Life Resources, Renmin University of China, Beijing 100872, China
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3
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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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4
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Satpathy JK, Yadav R, Bagha UK, Kumar D, Sastri CV, de Visser SP. Enhanced Reactivity through Equatorial Sulfur Coordination in Nonheme Iron(IV)-Oxo Complexes: Insights from Experiment and Theory. Inorg Chem 2024; 63:6752-6766. [PMID: 38551622 DOI: 10.1021/acs.inorgchem.4c00070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
Sulfur ligation in metalloenzymes often gives the active site unique properties, whether it is the axial cysteinate ligand in the cytochrome P450s or the equatorial sulfur/thiol ligation in nonheme iron enzymes. To understand sulfur ligation to iron complexes and how it affects the structural, spectroscopic, and intrinsic properties of the active species and the catalysis of substrates, we pursued a systematic study and compared sulfur with amine-ligated iron(IV)-oxo complexes. We synthesized and characterized a biomimetic N4S-ligated iron(IV)-oxo complex and compared the obtained results with an analogous N5-ligated iron(IV)-oxo complex. Our work shows that the amine for sulfur replacement in the equatorial ligand framework leads to a rate enhancement for oxygen atom and hydrogen atom transfer reactions. Moreover, the sulfur-ligated iron(IV)-oxo complex reacts through a different reaction mechanism as compared to the N5-ligated iron(IV)-oxo complex, where the former reacts through hydride transfer with the latter reacting via radical pathways. We show that the reactivity differences are caused by a dramatic change in redox potential between the two complexes. Our studies highlight the importance of implementing a sulfur ligand into the equatorial ligand framework of nonheme iron(IV)-oxo complexes and how it affects the physicochemical properties of the oxidant and its reactivity.
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Affiliation(s)
- Jagnyesh K Satpathy
- Department of Chemistry, Indian Institute of Technology, Guwahati 781039, Assam, India
| | - Rolly Yadav
- 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
| | - Devesh Kumar
- Department of Applied Physics, Babasaheb Bhimrao Ambedkar University, School for Physical Sciences, Vidya Vihar, Rae Bareilly Road, Lucknow 226025, UP, India
| | - 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
- The Manchester Institute of Biotechnology and Department of Chemical Engineering, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
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5
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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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6
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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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7
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Yang M, Chen X, Su X, She YB, Yang YF. Mechanistic Study of Chemoselectivity for Carbon Radical Hydroxylation versus Chlorination with Fe III (OH)(Cl) Complexes. Chem Asian J 2023; 18:e202201311. [PMID: 36705485 DOI: 10.1002/asia.202201311] [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: 12/31/2022] [Revised: 01/21/2023] [Accepted: 01/23/2023] [Indexed: 01/28/2023]
Abstract
The FeIII (OH)(Cl) complex resembles the key intermediate proposed for the non-heme iron halogenases. Goldberg and co-workers reported that the FeIII (OH)(Cl) RC reacts with triphenylmethyl radical 1 to give an exclusive hydroxylation product. To understand the chemoselectivity of the reaction of RC with 1, density functional theory (DFT) calculations have been conducted. From RC, the competing pathways were identified as the OH-transfer, Cl-transfer, and isomerization pathways. The direct Cl-transfer is more favorable than direct OH-transfer by 2.8 kcal/mol. The hydrogen bonding interactions between the hydroxyl group and the pendent amine ligand impede the direct OH-transfer from RC. Compared with the direct Cl-transfer pathway, the isomerization pathways require lower barriers. In isomer RCiso2 , the equatorial hydroxyl group, which has smaller diabatic bond dissociation energy, prefers to transfer to form the hydroxylation product. In FeIII (Cl)2 RC2 and RC2iso , the equatorial chloride group also prefers to transfer to give the chlorination product.
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Affiliation(s)
- Miao Yang
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang, 310014, P. R. China
| | - Xiahe Chen
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang, 310014, P. R. China
| | - Xingxing Su
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang, 310014, P. R. China
| | - Yuan-Bin She
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang, 310014, P. R. China
| | - Yun-Fang Yang
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang, 310014, P. R. China
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8
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Sen A, Rajaraman G. Can you break the oxo-wall? A multiconfigurational perspective. Faraday Discuss 2022; 234:175-194. [PMID: 35147623 DOI: 10.1039/d1fd00072a] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The concept of the "oxo-wall" was conceived about 60 years ago by Harry B. Gray, and has been found to be related to the non-existence of high-valent M-oxo species in the +IV oxidation state in a tetragonal geometry beyond group 8 in the periodic table. Several efforts have been made in the past decades to test and find examples that violate this theory. Several claims of violation in the past were attributed to the difference in the geometries/coordination number and, therefore, these are not examples of true violation. In recent years, substantial efforts have been undertaken to synthesise a true CoIVO species with various ligand architectures. CoIVO and CoIII-O˙ are electromers and, while they are interchangeably used in the literature; the former violates the oxo-wall while the latter does not. The possibility that these two species could exist in various proportions similar to resonating structures has not been considered in detail in this area. Furthermore, there have been no attempts to quantify such mixing. In this direction, we have employed density functional theory (DFT) and ab initio CASSCF/NEVPT2 methods to quantify the co-existence of CoIVO and CoIII-O˙ isomeric species. By thoroughly studying six different metal-oxo species, we affirm that the nature of such electromeric mixing is minimal/negligible for FeIVO and MnIVO species - both are pre-oxo-wall examples. By studying four different ligand architectures with Co-oxo species, our results unveil that the mixing of CoIVO ↔ CoIII-O˙ is substantial in all geometries, with dominant CoIVO species favourable for the S = 3/2 intermediate spin state. The percentage of the CoIII-O˙ species is enhanced substantially for the S = 1/2 low-spin state. We have attempted to develop a tool to estimate the percentage of the CoIII-O˙ species using various structural parameters. Among those tested, a linear relationship between % of CoIII-O˙ and a bond length based ratio is found (, where d(Co-O) and d(Co-Nax) are the axial Co-O and Co-Nax bond lengths in Å, respectively). It is found that the higher the Rd, the greater the CoIII-O˙ character will be and the geometrically portable correlation developed offers a way to qualitatively compute the % of CoIII-O˙ character for unknown geometries.
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Affiliation(s)
- Asmita Sen
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, 400076, India.
| | - Gopalan Rajaraman
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, 400076, India.
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9
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Li XX, Lu X, Park JW, Cho KB, Nam W. Nonheme Iron Imido Complexes Bearing a Non-Innocent Ligand: A Synthetic Chameleon Species in Oxidation Reactions. Chemistry 2021; 27:17495-17503. [PMID: 34590742 DOI: 10.1002/chem.202103295] [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: 09/10/2021] [Indexed: 11/07/2022]
Abstract
High-valent iron-imido complexes can perform C-H activation and sulfimidation reactions, but are far less studied than the more ubiquitous iron-oxo species. As case studies, we have looked at a recently published iron(V)-imido ligand π-cation radical complex, which is formally an iron(VI)-imido complex [FeV (NTs)(TAML+. )] (1; NTs=tosylimido), and an iron(V)-imido complex [FeV (NTs)(TAML)]- (2). Using a theoretical approach, we found that they have multiple energetically close-lying electromers, sometimes even without changing spin states, reminiscent of the so-called Compound I in Cytochrome P450. When studying their reactivity theoretically, it is indeed found that their electronic structures may change to perform efficient oxidations, emulating the multi-spin state reactivity in FeIV O systems. This is actually in contrast to the known [FeV (O)(TAML)]- species (3), where the reactions occur only on the ground spin state. We also looked into the whole reaction pathway for the C-H bond activation of 1,4-cyclohexadiene by these intermediates to reproduce the experimentally observed products, including steps that usually attract no interest (neither theoretically nor experimentally) due to their non-rate-limiting status and fast reactivity. A new "clustering non-rebound mechanism" is presented for this C-H activation reaction.
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Affiliation(s)
- Xiao-Xi Li
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 03760, Korea
| | - Xiaoyan Lu
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 03760, Korea
| | - Jae Woo Park
- Department of Chemistry, Chungbuk National University, Cheongju, 28644, Korea
| | - Kyung-Bin Cho
- Department of Chemistry, Jeonbuk National University, Jeonju, 54896, Korea
| | - Wonwoo Nam
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 03760, Korea
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10
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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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11
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Rydel-Ciszek K. The most reactive iron and manganese complexes with N-pentadentate ligands for dioxygen activation—synthesis, characteristics, applications. REACTION KINETICS MECHANISMS AND CATALYSIS 2021. [PMCID: PMC8204929 DOI: 10.1007/s11144-021-02008-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The iron and manganese complexes that activate oxygen atom play multiple role in technologically relevant reactions as well as in biological transformations, in which exist in different redox states. Among them, high-valent oxo intermediate seems to be the most important one. Iron, and/or manganese-based processes have found application in many areas, starting from catalysis and sustainable technologies, through DNA oxidative cleavage, to new substances useful in chemotherapeutic drugs. This review is not only the latest detailed list of uses of homogeneous N-pentadentate iron and manganese catalysts for syntheses of valuable molecules with huge applications in green technologies, but also a kind of "a cookbook", collecting "recipes" for the discussed complexes, in which the sources necessary to obtain a full characterization of the compounds are presented. Following the catalytic activity of metalloenzymes, and taking into account the ubiquity of iron and manganese salts, which in combination with properly designed ligands may show similarity to natural systems, the discussed complexes can find application as new anti-cancer drugs. Also, owing to ability of oxygen atom to exchange in reaction with H2O, they can be successfully applied in photodriven reactions of water oxidation, as well as in chemically regenerated fuel cells as a redox catalyst.
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Affiliation(s)
- Katarzyna Rydel-Ciszek
- Department of Physical Chemistry, Faculty of Chemistry, Rzeszów University of Technology, al. Powstańców Warszawy 6, P.O. Box 85, 35-959 Rzeszów, Poland
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12
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Biswas JP, Ansari M, Paik A, Sasmal S, Paul S, Rana S, Rajaraman G, Maiti D. Effect of the Ligand Backbone on the Reactivity and Mechanistic Paradigm of Non‐Heme Iron(IV)‐Oxo during Olefin Epoxidation. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202102484] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Jyoti Prasad Biswas
- Department of Chemistry Indian Institute of Technology Bombay Powai Mumbai 400076 India
| | - Mursaleem Ansari
- Department of Chemistry Indian Institute of Technology Bombay Powai Mumbai 400076 India
| | - Aniruddha Paik
- Department of Chemistry University of North Bengal Raja Rammohunpur Darjeeling West Bengal, Pin 734013 India
| | - Sheuli Sasmal
- Department of Chemistry Indian Institute of Technology Bombay Powai Mumbai 400076 India
| | - Sabarni Paul
- Department of Chemistry University of North Bengal Raja Rammohunpur Darjeeling West Bengal, Pin 734013 India
| | - Sujoy Rana
- Department of Chemistry University of North Bengal Raja Rammohunpur Darjeeling West Bengal, Pin 734013 India
| | - Gopalan Rajaraman
- Department of Chemistry Indian Institute of Technology Bombay Powai Mumbai 400076 India
| | - Debabrata Maiti
- Department of Chemistry Indian Institute of Technology Bombay Powai Mumbai 400076 India
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13
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Biswas JP, Ansari M, Paik A, Sasmal S, Paul S, Rana S, Rajaraman G, Maiti D. Effect of the Ligand Backbone on the Reactivity and Mechanistic Paradigm of Non-Heme Iron(IV)-Oxo during Olefin Epoxidation. Angew Chem Int Ed Engl 2021; 60:14030-14039. [PMID: 33836110 DOI: 10.1002/anie.202102484] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Indexed: 01/08/2023]
Abstract
The oxygen atom transfer (OAT) reactivity of the non-heme [FeIV (2PyN2Q)(O)]2+ (2) containing the sterically bulky quinoline-pyridine pentadentate ligand (2PyN2Q) has been thoroughly studied with different olefins. The ferryl-oxo complex 2 shows excellent OAT reactivity during epoxidations. The steric encumbrance and electronic effect of the ligand influence the mechanistic shuttle between OAT pathway I and isomerization pathway II (during the reaction stereo pure olefins), resulting in a mixture of cis-trans epoxide products. In contrast, the sterically less hindered and electronically different [FeIV (N4Py)(O)]2+ (1) provides only cis-stilbene epoxide. A Hammett study suggests the role of dominant inductive electronic along with minor resonance effect during electron transfer from olefin to 2 in the rate-limiting step. Additionally, a computational study supports the involvement of stepwise pathways during olefin epoxidation. The ferryl bend due to the bulkier ligand incorporation leads to destabilization of both d z 2 and d x 2 - y 2 orbitals, leading to a very small quintet-triplet gap and enhanced reactivity for 2 compared to 1. Thus, the present study unveils the role of steric and electronic effects of the ligand towards mechanistic modification during olefin epoxidation.
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Affiliation(s)
- Jyoti Prasad Biswas
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Mursaleem Ansari
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Aniruddha Paik
- Department of Chemistry, University of North Bengal, Raja Rammohunpur, Darjeeling, West Bengal, Pin, 734013, India
| | - Sheuli Sasmal
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Sabarni Paul
- Department of Chemistry, University of North Bengal, Raja Rammohunpur, Darjeeling, West Bengal, Pin, 734013, India
| | - Sujoy Rana
- Department of Chemistry, University of North Bengal, Raja Rammohunpur, Darjeeling, West Bengal, Pin, 734013, India
| | - Gopalan Rajaraman
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Debabrata Maiti
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
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14
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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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15
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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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16
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Wang C, Wu P, Wang Z, Wang B. The molecular mechanism of P450-catalyzed amination of the pyrrolidine derivative of lidocaine: insights from multiscale simulations. RSC Adv 2021; 11:27674-27680. [PMID: 35480638 PMCID: PMC9037892 DOI: 10.1039/d1ra04564d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Accepted: 08/09/2021] [Indexed: 11/23/2022] Open
Abstract
Nitrogen heterocycles are key and prevalent motifs in drugs. Evolved variants of cytochrome P450BM3 (CYP102A1) from Bacillus megaterium employ high-valent oxo-iron(iv) species to catalyze the synthesis of imidazolidine-4-ones via an intramolecular C–H amination. Herein, we use multi-scale simulations, including classical molecular dynamics (MD) simulations, quantum mechanical/molecular mechanical (QM/MM) calculations and QM calculations, to reveal the molecular mechanism of the intramolecular C–H amination of the pyrrolidine derivative of lidocaine bearing cyclic amino moieties catalyzed by the variant RP/FV/EV of P450BM3, which bears five mutations compared to wild type. Our calculations show that overall catalysis includes both the enzymatic transformation in P450 and non-enzymatic transformation in water solution. The enzymatic transformation involves the exclusive hydroxylation of the C–H bond of the pyrrolidine derivative of lidocaine, leading to the hydroxylated intermediate, during which the substrate radical would be bypassed. The following dehydration and C–N coupling reactions are found to be much favored in aqueous situation compared to that in the non-polar protein environment. The present findings expand our understanding of the P450-catalyzed C(sp3)–H amination reaction. Nitrogen heterocycles are key and prevalent motifs in drugs.![]()
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Affiliation(s)
- Conger Wang
- State Key Laboratory of Physical Chemistry of Solid Surface, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China
| | - Peng Wu
- State Key Laboratory of Physical Chemistry of Solid Surface, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China
| | - Zhanfeng Wang
- State Key Laboratory of Physical Chemistry of Solid Surface, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China
| | - Binju Wang
- State Key Laboratory of Physical Chemistry of Solid Surface, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China
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17
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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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18
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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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19
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Ali HS, Henchman RH, de Visser SP. What Determines the Selectivity of Arginine Dihydroxylation by the Nonheme Iron Enzyme OrfP? Chemistry 2020; 27:1795-1809. [PMID: 32965733 DOI: 10.1002/chem.202004019] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 09/22/2020] [Indexed: 12/13/2022]
Abstract
The nonheme iron enzyme OrfP reacts with l-Arg selectively to form the 3R,4R-dihydroxyarginine product, which in mammals can inhibit the nitric oxide synthase enzymes involved in blood pressure control. To understand the mechanisms of dioxygen activation of l-Arg by OrfP and how it enables two sequential oxidation cycles on the same substrate, we performed a density functional theory study on a large active site cluster model. We show that substrate binding and positioning in the active site guides a highly selective reaction through C3 -H hydrogen atom abstraction. This happens despite the fact that the C3 -H and C4 -H bond strengths of l-Arg are very similar. Electronic differences in the two hydrogen atom abstraction pathways drive the reaction with an initial C3 -H activation to a low-energy 5 σ-pathway, while substrate positioning destabilizes the C4 -H abstraction and sends it over the higher-lying 5 π-pathway. We show that substrate and monohydroxylated products are strongly bound in the substrate binding pocket and hence product release is difficult and consequently its lifetime will be long enough to trigger a second oxygenation cycle.
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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 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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20
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Kumar R, Pandey B, Sen A, Ansari M, Sharma S, Rajaraman G. Role of oxidation state, ferryl-oxygen, and ligand architecture on the reactivity of popular high-valent FeIV=O species: A theoretical perspective. Coord Chem Rev 2020. [DOI: 10.1016/j.ccr.2020.213397] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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21
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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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22
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Roy L. Theoretical Identification of the Factors Governing the Reactivity of C-H Bond Activation by Non-Heme Iron(IV)-Oxo Complexes. Chempluschem 2020; 84:893-906. [PMID: 31943994 DOI: 10.1002/cplu.201900178] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 05/30/2019] [Indexed: 11/06/2022]
Abstract
Selective functionalization of C-H bonds provides a straightforward approach to a large variety of well-defined derivatives. High-valent mononuclear iron(IV)-oxo complexes are proposed to carry out these C-H activation reactions in enzymes or in biomimetic syntheses. In this Minireview, we aim to highlight the features that delineate the distinct reactivity of non-heme oxo-iron(IV) motifs to cleave strong C-H bonds in hydrocarbons, primarily focusing on the hydrogen atom transfer (HAT) process. We describe how the structural and electronic properties of supporting ligands modulate the oxidative property of the iron(IV)-oxo complexes. Furthermore, we highlight the decisive role played by spin-state in these biomimetic reactions. We also discuss how tunneling and external perturbations like electric field influence the transfer of hydrogen atoms. Lastly, we emphasize how computations could work as a practical guide to sketch and develop synthetic models with greater efficacy.
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Affiliation(s)
- Lisa Roy
- Institute of Chemical Technology Mumbai IOC Odisha Campus Bhubaneswar, IIT Kharagpur Extension Centre, Bhubaneswar, 751013, Odisha, India
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23
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Tripathi A, Chetti P. Enhanced charge transport properties in heteroatomic (NH, O, Se) analogs of benzotrithiophene (BTT) isomers: a DFT insight. MOLECULAR SIMULATION 2020. [DOI: 10.1080/08927022.2020.1738425] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Anuj Tripathi
- Department of Chemistry, National Institute of Technology, Kurukshetra, India
| | - Prabhakar Chetti
- Department of Chemistry, National Institute of Technology, Kurukshetra, India
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24
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The oxidation of cyclo-olefin by the S = 2 ground-state complex [Fe IV(O)(TQA)(NCMe)] 2. J Biol Inorg Chem 2020; 25:371-382. [PMID: 32133579 DOI: 10.1007/s00775-020-01768-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 02/16/2020] [Indexed: 10/24/2022]
Abstract
Density functional theory calculation is used to investigate the oxidation of cyclo-olefin (cyclobutene, cyclopentene, cyclohexene, cycloheptene, and cyclo-octene) by the complex [FeIV(O)(TQA)(NCMe)]2+, which has S = 2 ground state, and the effect of electronic factors and steric hindrance on reaction barriers. Our results suggest that the oxo-iron(IV) complex can oxidise C-H and C = C bonds via a single-state mechanism, and two different ways of electron transport exist. The energy barriers initially decrease with increasing substrate size, and the trend then reverses. Comparison of the energy barrier in different systems reveals that except for the reaction between [FeIV(O)(TQA)(NCMe)]2+ and cycloheptene, oxo-iron(IV) complexes prefer epoxidation to hydroxylation. However, the hydroxylated product is more stable than the corresponding epoxidated product. This result indicates that the products of epoxidation tend to decompose first. The energy barrier of hydroxylation and epoxidation originates from the balance of orbital interaction and Pauli repulsion from the equatorial ligand and protons on the approaching substrate. In this regard, we calculate the weak interaction between two fragments (oxo-iron complex and substrates) using the independent gradient model and drawn the corresponding 3D isosurface representations of reactants.
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25
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Wang M, Qu Z. The C–H bond activation by non-heme oxidant [(N4Py)FeIV(O)]2+ with external electric field. Theor Chem Acc 2020. [DOI: 10.1007/s00214-020-2581-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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26
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Maldonado-Domínguez M, Srnec M. Understanding and Predicting Post H-Atom Abstraction Selectivity through Reactive Mode Composition Factor Analysis. J Am Chem Soc 2020; 142:3947-3958. [PMID: 32000494 DOI: 10.1021/jacs.9b12800] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The selective functionalization of C-H bonds is one of the Grails of synthetic chemistry. In this work, we demonstrate that the selectivity toward fast hydroxylation or radical diffusion (known as the OH-rebound and dissociation mechanisms) following H-atom abstraction (HAA) from a substrate C-H bond by high-valent iron-oxo oxidants is already encoded in the HAA step when the post-HAA barriers are much lower than the preceding one. By applying the reactive mode composition factor (RMCF) analysis, which quantifies the kinetic energy distribution (KED) at the reactive mode (RM) of transition states, we show that reactions following the OH-rebound coordinate concentrate the RM kinetic energy on the motion of the reacting oxygen atom and the nascent substrate radical, whereas reactions following the dissociation channel localize most of their kinetic energy in H-atom motion. These motion signatures serve to predict the post-HAA selectivity, and since KED is affected by the free energy of reaction and asynchronicity (factor η) of HAA, we show that bimolecular HAA reactions in solution that are electron transfer-driven and highly exergonic have the lowest fraction of KED on the transferred H-atom and the highest chance to follow rebound hydroxylation. Finally, the RMCF analysis predicts that the H/D primary kinetic isotope effect can serve as a probe for these mechanisms, as confirmed in virtually all reported examples in the literature.
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Affiliation(s)
- Mauricio Maldonado-Domínguez
- J. Heyrovský Institute of Physical Chemistry, The Czech Academy of Sciences , Dolejškova 3 , Prague 8 18223 , Czech Republic
| | - Martin Srnec
- J. Heyrovský Institute of Physical Chemistry, The Czech Academy of Sciences , Dolejškova 3 , Prague 8 18223 , Czech Republic
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27
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Li H, Liu Y. Mechanistic Investigation of Isonitrile Formation Catalyzed by the Nonheme Iron/α-KG-Dependent Decarboxylase (ScoE). ACS Catal 2020. [DOI: 10.1021/acscatal.9b05411] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Hong Li
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan, Shandong 250100, China
| | - Yongjun Liu
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan, Shandong 250100, China
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28
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Monika, Ansari A. Mechanistic insights into the allylic oxidation of aliphatic compounds by tetraamido iron( v) species: A C–H vs. O–H bond activation. NEW J CHEM 2020. [DOI: 10.1039/d0nj03095c] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This work is based on a deep insight into a comparative study of C–H vs. O–H bond activation of allylic compound by the high valent iron complex. Our theoretical findings can help to design catalysts with better efficiency for catalytic reactions.
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Affiliation(s)
- Monika
- Department of Chemistry
- Central University of Haryana
- Mahendergarh-123031
- India
| | - Azaj Ansari
- Department of Chemistry
- Central University of Haryana
- Mahendergarh-123031
- India
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29
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Fukuzumi S, Cho KB, Lee YM, Hong S, Nam W. Mechanistic dichotomies in redox reactions of mononuclear metal–oxygen intermediates. Chem Soc Rev 2020; 49:8988-9027. [DOI: 10.1039/d0cs01251c] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This review article focuses on various mechanistic dichotomies in redox reactions of metal–oxygen intermediates with the emphasis on understanding and controlling their redox reactivity from experimental and theoretical points of view.
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Affiliation(s)
- Shunichi Fukuzumi
- Department of Chemistry and Nano Science
- Ewha Womans University
- Seoul 03760
- Korea
- Graduate School of Science and Engineering
| | - Kyung-Bin Cho
- Department of Chemistry
- Jeonbuk National University
- Jeonju 54896
- Korea
| | - Yong-Min Lee
- Department of Chemistry and Nano Science
- Ewha Womans University
- Seoul 03760
- Korea
| | - Seungwoo Hong
- Department of Chemistry
- Sookmyung Women's University
- Seoul 04310
- Korea
| | - Wonwoo Nam
- Department of Chemistry and Nano Science
- Ewha Womans University
- Seoul 03760
- Korea
- School of Chemistry and Chemical Engineering
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30
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Feldt M, Martín-Fernández C, Harvey JN. Energetics of non-heme iron reactivity: can ab initio calculations provide the right answer? Phys Chem Chem Phys 2020; 22:23908-23919. [DOI: 10.1039/d0cp04401f] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We use a variety of computational methods to characterize and compare the hydrogen atom transfer (HAT) and epoxidation reaction pathways for oxidation of cyclohexene by an iron(iv)-oxo complex.
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Affiliation(s)
- Milica Feldt
- Division of Quantum Chemistry and Physical Chemistry
- Department of Chemistry
- Katholieke Universiteit Leuven
- 3001 Leuven
- Belgium
| | - Carlos Martín-Fernández
- Division of Quantum Chemistry and Physical Chemistry
- Department of Chemistry
- Katholieke Universiteit Leuven
- 3001 Leuven
- Belgium
| | - Jeremy N. Harvey
- Division of Quantum Chemistry and Physical Chemistry
- Department of Chemistry
- Katholieke Universiteit Leuven
- 3001 Leuven
- Belgium
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31
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Mukherjee G, Reinhard FGC, Bagha UK, Sastri CV, de Visser SP. Sluggish reactivity by a nonheme iron(iv)-tosylimido complex as compared to its oxo analogue. Dalton Trans 2020; 49:5921-5931. [DOI: 10.1039/d0dt00018c] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A comparative spectroscopic and computational study of reactivity between ferryl-tosylimido and ferryl-oxo complexes of two biomimetic model systems. The Fe(iv)-tosylimido complex was found to be sluggish in comparison to its fellow oxo counterpart.
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Affiliation(s)
- Gourab Mukherjee
- Department of Chemistry
- Indian Institute of Technology Guwahati
- India
| | - Fabián G. Cantú Reinhard
- The Manchester Institute of Biotechnology and Department of Chemical Engineering and Analytical Science
- The University of Manchester
- Manchester M1 7DN
- UK
| | | | | | - Sam P. de Visser
- The Manchester Institute of Biotechnology and Department of Chemical Engineering and Analytical Science
- The University of Manchester
- Manchester M1 7DN
- UK
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32
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Lin Y, Stańczak A, Manchev Y, Straganz GD, Visser SP. Can a Mononuclear Iron(III)‐Superoxo Active Site Catalyze the Decarboxylation of Dodecanoic Acid in UndA to Produce Biofuels? Chemistry 2019; 26:2233-2242. [DOI: 10.1002/chem.201903783] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 09/24/2019] [Indexed: 12/22/2022]
Affiliation(s)
- Yen‐Ting Lin
- The Manchester Institute of Biotechnology and Department of, Chemical Engineering and Analytical ScienceThe University of, Manchester 131 Princess Street Manchester M1 7DN UK
| | - Agnieszka Stańczak
- The Manchester Institute of Biotechnology and Department of, Chemical Engineering and Analytical ScienceThe University of, Manchester 131 Princess Street Manchester M1 7DN UK
- Faculty of ChemistrySilesian University of Technology ks. Marcina Strzody 9 44-100 Gliwice Poland
- Tunneling Group, Biotechnology CentreSilesian University of Technology ul. Krzywoustego 8 44–100 Gliwice Poland
| | - Yulian Manchev
- The Manchester Institute of Biotechnology and Department of, Chemical Engineering and Analytical ScienceThe University of, Manchester 131 Princess Street Manchester M1 7DN UK
| | - Grit D. Straganz
- Graz University of TechnologyInstitute of Biochemistry Petergasse 12 8010 Graz Austria
| | - Sam P. Visser
- The Manchester Institute of Biotechnology and Department of, Chemical Engineering and Analytical ScienceThe University of, Manchester 131 Princess Street Manchester M1 7DN UK
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33
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Mubarak MQE, de Visser SP. Reactivity patterns of vanadium(iv/v)-oxo complexes with olefins in the presence of peroxides: a computational study. Dalton Trans 2019; 48:16899-16910. [PMID: 31670737 DOI: 10.1039/c9dt03048d] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Vanadium porphyrin complexes are naturally occurring substances found in crude oil and have been shown to have medicinal properties as well. Little is known on their activities with substrates; therefore, we decided to perform a detailed density functional theory study on the properties and reactivities of vanadium(iv)- and vanadium(v)-oxo complexes with a TPPCl8 or 2,3,7,8,12,13,17,18-octachloro-meso-tetraphenylporphyrinato ligand system. In particular, we investigated the reactivity of [VV(O)(TPPCl8)]+ and [VIV(O)(TPPCl8)] with cyclohexene in the presence of H2O2 or HCO4-. The work shows that vanadium(iv)-oxo and vanadium(v)-oxo are sluggish oxidants by themselves and react with olefins slowly. However, in the presence of hydrogen peroxide, these metal-oxo species can be transformed into a side-on vanadium-peroxo complex, which reacts with substrates more efficiently. Particularly with anionic axial ligands, the side-on vanadium-peroxo and vanadium-oxo complexes produced epoxides from cyclohexene via small barrier heights. In addition to olefin epoxidation, we investigated aliphatic hydroxylation mechanisms by the same oxidants and some oxidants show efficient and viable cyclohexene hydroxylation mechanisms. The work implies that vanadium-oxo and vanadium-peroxo complexes can react with double bonds through epoxidation, and under certain conditions also undergo hydroxylation, but the overall reactivity is highly dependent on the equatorial ligand, the local environment and the presence or absence of anionic axial ligands.
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Affiliation(s)
- M Qadri E Mubarak
- The Manchester Institute of Biotechnology and Department of Chemical Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK.
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34
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Zima AM, Lyakin OY, Bryliakov KP, Talsi EP. High‐Spin and Low‐Spin Perferryl Intermediates in Fe(PDP)‐Catalyzed Epoxidations. ChemCatChem 2019. [DOI: 10.1002/cctc.201900842] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Alexandra M. Zima
- Boreskov Institute of Catalysis Pr. Lavrentieva 5 Novosibirsk 630090 Russia
- Novosibirsk State University Pirogova 2 Novosibirsk 630090 Russia
| | - Oleg Y. Lyakin
- Boreskov Institute of Catalysis Pr. Lavrentieva 5 Novosibirsk 630090 Russia
- Novosibirsk State University Pirogova 2 Novosibirsk 630090 Russia
| | - Konstantin P. Bryliakov
- Boreskov Institute of Catalysis Pr. Lavrentieva 5 Novosibirsk 630090 Russia
- Novosibirsk State University Pirogova 2 Novosibirsk 630090 Russia
| | - Evgenii P. Talsi
- Boreskov Institute of Catalysis Pr. Lavrentieva 5 Novosibirsk 630090 Russia
- Novosibirsk State University Pirogova 2 Novosibirsk 630090 Russia
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35
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Phung QM, Martín-Fernández C, Harvey JN, Feldt M. Ab Initio Calculations for Spin-Gaps of Non-Heme Iron Complexes. J Chem Theory Comput 2019; 15:4297-4304. [DOI: 10.1021/acs.jctc.9b00370] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Quan Manh Phung
- Department of Chemistry, KU Leuven, Celestijnenlaan 200f, Box 2404, 3001 Leuven, Belgium
| | | | - Jeremy N. Harvey
- Department of Chemistry, KU Leuven, Celestijnenlaan 200f, Box 2404, 3001 Leuven, Belgium
| | - Milica Feldt
- Department of Chemistry, KU Leuven, Celestijnenlaan 200f, Box 2404, 3001 Leuven, Belgium
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36
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37
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Mukherjee G, Alili A, Barman P, Kumar D, Sastri CV, de Visser SP. Interplay Between Steric and Electronic Effects: A Joint Spectroscopy and Computational Study of Nonheme Iron(IV)-Oxo Complexes. Chemistry 2019; 25:5086-5098. [PMID: 30720909 DOI: 10.1002/chem.201806430] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Indexed: 01/05/2023]
Abstract
Iron is an essential element in nonheme enzymes that plays a crucial role in many vital oxidative transformations and metabolic reactions in the human body. Many of those reactions are regio- and stereospecific and it is believed that the selectivity is guided by second-coordination sphere effects in the protein. Here, results are shown of a few engineered biomimetic ligand frameworks based on the N4Py (N,N-bis(2-pyridylmethyl)-N-bis(2-pyridyl)methylamine) scaffold and the second-coordination sphere effects are studied. For the first time, selective substitutions in the ligand framework have been shown to tune the catalytic properties of the iron(IV)-oxo complexes by regulating the steric and electronic factors. In particular, a better positioning of the oxidant and substrate in the rate-determining transition state lowers the reaction barriers. Therefore, an optimum balance between steric and electronic factors mediates the ideal positioning of oxidant and substrate in the rate-determining transition state that affects the reactivity of high-valent reaction intermediates.
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Affiliation(s)
- Gourab Mukherjee
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India
| | - Aligulu Alili
- The Manchester Institute of Biotechnology and School of Chemical, Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
| | - Prasenjit Barman
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India
| | - Devesh Kumar
- Department of Applied Physics, Babasaheb Bhimrao Ambedkar University, School for Physical Sciences, Vidya Vihar, Rae Bareilly Road, Lucknow, 226025, UP, India
| | - Chivukula V Sastri
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India
| | - Sam P de Visser
- The Manchester Institute of Biotechnology and School of Chemical, Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
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38
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Stoyanovsky DA, Tyurina YY, Shrivastava I, Bahar I, Tyurin VA, Protchenko O, Jadhav S, Bolevich SB, Kozlov AV, Vladimirov YA, Shvedova AA, Philpott CC, Bayir H, Kagan VE. Iron catalysis of lipid peroxidation in ferroptosis: Regulated enzymatic or random free radical reaction? Free Radic Biol Med 2019; 133:153-161. [PMID: 30217775 PMCID: PMC6555767 DOI: 10.1016/j.freeradbiomed.2018.09.008] [Citation(s) in RCA: 222] [Impact Index Per Article: 44.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 09/06/2018] [Accepted: 09/09/2018] [Indexed: 12/14/2022]
Abstract
Duality of iron as an essential cofactor of many enzymatic metabolic processes and as a catalyst of poorly controlled redox-cycling reactions defines its possible biological beneficial and hazardous role in the body. In this review, we discuss these two "faces" of iron in a newly conceptualized program of regulated cell death, ferroptosis. Ferroptosis is a genetically programmed iron-dependent form of regulated cell death driven by enhanced lipid peroxidation and insufficient capacity of thiol-dependent mechanisms (glutathione peroxidase 4, GPX4) to eliminate hydroperoxy-lipids. We present arguments favoring the enzymatic mechanisms of ferroptotically engaged non-heme iron of 15-lipoxygenases (15-LOX) in complexes with phosphatidylethanolamine binding protein 1 (PEBP1) as a catalyst of highly selective and specific oxidation reactions of arachidonoyl- (AA) and adrenoyl-phosphatidylethanolamines (PE). We discuss possible role of iron chaperons as control mechanisms for guided iron delivery directly to their "protein clients" thus limiting non-enzymatic redox-cycling reactions. We also consider opportunities of loosely-bound iron to contribute to the production of pro-ferroptotic lipid oxidation products. Finally, we propose a two-stage iron-dependent mechanism for iron in ferroptosis by combining its catalytic role in the 15-LOX-driven production of 15-hydroperoxy-AA-PE (HOO-AA-PE) as well as possible involvement of loosely-bound iron in oxidative cleavage of HOO-AA-PE to oxidatively truncated electrophiles capable of attacking nucleophilic targets in yet to be identified proteins leading to cell demise.
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Affiliation(s)
- D A Stoyanovsky
- Center for Free Radical and Antioxidant Heath, Department of Environmental Health, University of Pittsburgh, USA
| | - Y Y Tyurina
- Center for Free Radical and Antioxidant Heath, Department of Environmental Health, University of Pittsburgh, USA
| | - I Shrivastava
- Center for Free Radical and Antioxidant Heath, Department of Environmental Health, University of Pittsburgh, USA; Department of Computational and Systems Biology, University of Pittsburgh, USA
| | - I Bahar
- Department of Computational and Systems Biology, University of Pittsburgh, USA
| | - V A Tyurin
- Center for Free Radical and Antioxidant Heath, Department of Environmental Health, University of Pittsburgh, USA
| | - O Protchenko
- Genetics and Metabolism Section, Liver Diseases Branch, NIDDK, NIH, Bethesda, USA
| | - S Jadhav
- Genetics and Metabolism Section, Liver Diseases Branch, NIDDK, NIH, Bethesda, USA
| | - S B Bolevich
- Laboratory of Navigational Redox Lipidomics and Department of Human Pathology, IM Sechenov Moscow State Medical University, Russian Federation
| | - A V Kozlov
- L Boltzmann Institute for Experimental and Clinical Traumatology in AUVA Research Center, Vienna, Austria; Laboratory of Navigational Redox Lipidomics and Department of Human Pathology, IM Sechenov Moscow State Medical University, Russian Federation
| | - Y A Vladimirov
- Laboratory of Navigational Redox Lipidomics and Department of Human Pathology, IM Sechenov Moscow State Medical University, Russian Federation
| | - A A Shvedova
- Exposure Assessment Branch, NIOSH/CDC, Morgantown, WV, USA
| | - C C Philpott
- Genetics and Metabolism Section, Liver Diseases Branch, NIDDK, NIH, Bethesda, USA
| | - H Bayir
- Center for Free Radical and Antioxidant Heath, Department of Environmental Health, University of Pittsburgh, USA; Departments of Critical Care Medicine, University of Pittsburgh, USA
| | - V E Kagan
- Center for Free Radical and Antioxidant Heath, Department of Environmental Health, University of Pittsburgh, USA; Laboratory of Navigational Redox Lipidomics and Department of Human Pathology, IM Sechenov Moscow State Medical University, Russian Federation; Departments of Chemistry, University of Pittsburgh, USA; Departments of Pharmacology and Chemical Biology, University of Pittsburgh, USA; Departments of Radiation Oncology, University of Pittsburgh, USA.
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39
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Feldt M, Phung QM, Pierloot K, Mata RA, Harvey JN. Limits of Coupled-Cluster Calculations for Non-Heme Iron Complexes. J Chem Theory Comput 2019; 15:922-937. [PMID: 30605326 DOI: 10.1021/acs.jctc.8b00963] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
In a large variety of studies, the coupled-cluster method with singles, doubles, and perturbative triples (CCSD(T)) is used as a reference for benchmarking the performance of density functional theory (DFT) functionals. In the case of open-shell species, this theory can be applied in different forms depending on the restricted or unrestricted treatment of spin. In this study, we show that these different approaches can produce results which deviate by ∼5 kcal/mol for different species on the potential energy surfaces. This was demonstrated for a simple model of the C-H activation carried out by non-heme iron enzymes. Assessing the limits of CCSD(T) prior to its use as a general benchmark tool is warranted. This was done using higher-order coupled-cluster calculations as well as multiconfigurational second-order perturbation theory (CASPT2), since iron-oxo species present some multireference character. Furthermore, we tested two different implementations of the local coupled-cluster method and compared them to the CCSD(T) results, showing that even though these novel approaches are promising, without further developments they appear not to be suitable for describing two-state reactivity of the system investigated in the current study. Additionally, we implemented and assessed the performance of the hotspot approach for the local unrestricted CCSD(T) scheme which aims at reducing the pair error for systems containing transition metals.
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Affiliation(s)
- Milica Feldt
- Department of Chemistry , KU Leuven , Celestijnenlaan 200f, Box 2404, 3001 Leuven , Belgium
| | - Quan Manh Phung
- Department of Chemistry , KU Leuven , Celestijnenlaan 200f, Box 2404, 3001 Leuven , Belgium
| | - Kristine Pierloot
- Department of Chemistry , KU Leuven , Celestijnenlaan 200f, Box 2404, 3001 Leuven , Belgium
| | - Ricardo A Mata
- Institut für Physikalische Chemie , Universität Göttingen , Tammannstrasse 6 , D-37077 Göttingen , Germany
| | - Jeremy N Harvey
- Department of Chemistry , KU Leuven , Celestijnenlaan 200f, Box 2404, 3001 Leuven , Belgium
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40
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Rana S, Biswas JP, Sen A, Clémancey M, Blondin G, Latour JM, Rajaraman G, Maiti D. Selective C-H halogenation over hydroxylation by non-heme iron(iv)-oxo. Chem Sci 2018; 9:7843-7858. [PMID: 30429994 PMCID: PMC6194801 DOI: 10.1039/c8sc02053a] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 08/14/2018] [Indexed: 12/26/2022] Open
Abstract
Non-heme iron based halogenase enzymes promote selective halogenation of the sp3-C-H bond through iron(iv)-oxo-halide active species. During halogenation, competitive hydroxylation can be prevented completely in enzymatic systems. However, synthetic iron(iv)-oxo-halide intermediates often result in a mixture of halogenation and hydroxylation products. In this report, we have developed a new synthetic strategy by employing non-heme iron based complexes for selective sp3-C-H halogenation by overriding hydroxylation. A room temperature stable, iron(iv)-oxo complex, [Fe(2PyN2Q)(O)]2+ was directed for hydrogen atom abstraction (HAA) from aliphatic substrates and the iron(ii)-halide [FeII(2PyN2Q)(X)]+ (X, halogen) was exploited in conjunction to deliver the halogen atom to the ensuing carbon centered radical. Despite iron(iv)-oxo being an effective promoter of hydroxylation of aliphatic substrates, the perfect interplay of HAA and halogen atom transfer in this work leads to the halogenation product selectively by diverting the hydroxylation pathway. Experimental studies outline the mechanistic details of the iron(iv)-oxo mediated halogenation reactions. A kinetic isotope study between PhCH3 and C6D5CD3 showed a value of 13.5 that supports the initial HAA step as the RDS during halogenation. Successful implementation of this new strategy led to the establishment of a functional mimic of non-heme halogenase enzymes with an excellent selectivity for halogenation over hydroxylation. Detailed theoretical studies based on density functional methods reveal how the small difference in the ligand design leads to a large difference in the electronic structure of the [Fe(2PyN2Q)(O)]2+ species. Both experimental and computational studies suggest that the halide rebound process of the cage escaped radical with iron(iii)-halide is energetically favorable compared to iron(iii)-hydroxide and it brings in selective formation of halogenation products over hydroxylation.
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Affiliation(s)
- Sujoy Rana
- Department of Chemistry , IIT Bombay , Powai , Mumbai-400076 , India
| | | | - Asmita Sen
- Department of Chemistry , IIT Bombay , Powai , Mumbai-400076 , India
| | - Martin Clémancey
- University of Grenoble Alpes , LCBM/PMB and CEA , IRTSV/CBM/PMB and CNRS , LCBM UMR 5249, PMB , 38000 Grenoble , France
| | - Geneviève Blondin
- University of Grenoble Alpes , LCBM/PMB and CEA , IRTSV/CBM/PMB and CNRS , LCBM UMR 5249, PMB , 38000 Grenoble , France
| | - Jean-Marc Latour
- University of Grenoble Alpes , LCBM/PMB and CEA , IRTSV/CBM/PMB and CNRS , LCBM UMR 5249, PMB , 38000 Grenoble , France
| | - Gopalan Rajaraman
- Department of Chemistry , IIT Bombay , Powai , Mumbai-400076 , India
| | - Debabrata Maiti
- Department of Chemistry , IIT Bombay , Powai , Mumbai-400076 , India
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41
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Chen J, Draksharapu A, Angelone D, Unjaroen D, Padamati SK, Hage R, Swart M, Duboc C, Browne WR. H 2O 2 Oxidation by Fe III-OOH Intermediates and Its Effect on Catalytic Efficiency. ACS Catal 2018; 8:9665-9674. [PMID: 30319886 PMCID: PMC6179451 DOI: 10.1021/acscatal.8b02326] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 08/30/2018] [Indexed: 11/28/2022]
Abstract
![]()
The
oxidation of the C–H and C=C bonds of hydrocarbons with
H2O2 catalyzed by non-heme iron complexes with
pentadentate ligands is widely accepted as involving a reactive FeIV=O species such as [(N4Py)FeIV=O]2+ formed by homolytic cleavage of the O–O bond of an
FeIII–OOH intermediate (where N4Py is 1,1-bis(pyridin-2-yl)-N,N-bis(pyridin-2-ylmethyl)methanamine).
We show here that at low H2O2 concentrations
the FeIV=O species formed is detectable in methanol.
Furthermore, we show that the decomposition of H2O2 to water and O2 is an important competing pathway
that limits efficiency in the terminal oxidant and indeed dominates
reactivity except where only sub-/near-stoichiometric amounts of H2O2 are present. Although independently prepared
[(N4Py)FeIV=O]2+ oxidizes stoichiometric
H2O2 rapidly, the rate of formation of FeIV=O from the FeIII–OOH intermediate
is too low to account for the rate of H2O2 decomposition
observed under catalytic conditions. Indeed, with excess H2O2, disproportionation to O2 and H2O is due to reaction with the FeIII–OOH intermediate
and thereby prevents formation of the FeIV=O species.
These data rationalize that the activity of these catalysts with respect
to hydrocarbon/alkene oxidation is maximized by maintaining sub-/near-stoichiometric
steady-state concentrations of H2O2, which ensure
that the rate of the H2O2 oxidation by the FeIII–OOH intermediate is less than the rate of the O–O
bond homolysis and the subsequent reaction of the FeIV=O
species with a substrate.
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Affiliation(s)
- Juan Chen
- Molecular Inorganic Chemistry, Stratingh Institute for Chemistry, Faculty of Science and Engineering, University of Groningen, Nijenborgh 4, 9747AG, Groningen, The Netherlands
| | - Apparao Draksharapu
- Molecular Inorganic Chemistry, Stratingh Institute for Chemistry, Faculty of Science and Engineering, University of Groningen, Nijenborgh 4, 9747AG, Groningen, The Netherlands
| | - Davide Angelone
- Molecular Inorganic Chemistry, Stratingh Institute for Chemistry, Faculty of Science and Engineering, University of Groningen, Nijenborgh 4, 9747AG, Groningen, The Netherlands
- Institut de Química Computacional i Catàlisi (IQCC), Departament de Química, Universitat de Girona, Campus Montilivi, E17003 Girona, Catalonia, Spain
| | - Duenpen Unjaroen
- Molecular Inorganic Chemistry, Stratingh Institute for Chemistry, Faculty of Science and Engineering, University of Groningen, Nijenborgh 4, 9747AG, Groningen, The Netherlands
| | - Sandeep K. Padamati
- Molecular Inorganic Chemistry, Stratingh Institute for Chemistry, Faculty of Science and Engineering, University of Groningen, Nijenborgh 4, 9747AG, Groningen, The Netherlands
| | - Ronald Hage
- Catexel BV, BioPartner Center, Galileiweg 8, 2333BD Leiden, The Netherlands
| | - Marcel Swart
- Institut de Química Computacional i Catàlisi (IQCC), Departament de Química, Universitat de Girona, Campus Montilivi, E17003 Girona, Catalonia, Spain
- ICREA, Pg. Lluís Companys 23, 08010 Barcelona, Spain
| | - Carole Duboc
- Departement de Chimie Moleculaire, Univ. Grenoble Alpes/CNRS, UMR-5250, BP-53, 38041 Grenoble Cedex 9, France
| | - Wesley R. Browne
- Molecular Inorganic Chemistry, Stratingh Institute for Chemistry, Faculty of Science and Engineering, University of Groningen, Nijenborgh 4, 9747AG, Groningen, The Netherlands
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42
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Yang L, Chen X, Qu Z, Gao J. Combined Multistate and Kohn-Sham Density Functional Theory Studies of the Elusive Mechanism of N-Dealkylation of N,N-Dimethylanilines Mediated by the Biomimetic Nonheme Oxidant Fe IV(O)(N4Py)(ClO 4) 2. Front Chem 2018; 6:406. [PMID: 30250841 PMCID: PMC6139341 DOI: 10.3389/fchem.2018.00406] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 08/20/2018] [Indexed: 11/13/2022] Open
Abstract
The oxidative C-H bond activation mediated by heme and nonheme enzymes and related biomimetics is one of the most interesting processes in bioinorganic and oxidative chemistry. However, the mechanisms of these reactions are still elusive and controversy due to the involvement of highly reactive metal-oxo intermediates with multiple spin states, despite extensive experimental efforts, especially for the N-dealkylation of N,N-dialkyalinines. In this work, we employed multistate density functional theory (MSDFT) and the Kohn-Sham DFT to investigate the mechanism of N-demethylation of N,N-dimethyalinines oxidized by the reaction intermediate FeIV(O)(N4Py)(ClO4)2. The Kohn-Sham DFT study demonstrated that the reaction proceeds via a rate-limiting hydrogen atom transfer (HAT) step and a subsequent barrier-free oxygen rebound step to form the carbinol product. The MSDFT investigation on the first C-H activation further showed that this step is an initial hydrogen atom abstraction that is highly correlated between CEPT and HAT, i.e., both CEPT and HAT processes make significant contributions to the mechanism before reaching the diabatic crossing point, then the valence bond character of the adiabatic ground state is switched to the CEPT product configuration. The findings from this work may be applicable to other hydrogen abstraction process.
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Affiliation(s)
- Lili Yang
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun, China
| | - Xin Chen
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun, China
| | - Zexing Qu
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun, China
| | - Jiali Gao
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun, China.,Department of Chemistry, University of Minnesota, Minneapolis, MN, United States
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43
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Gheidi M, Safari N, Zahedi M. Density functional theory studies on the conversion of hydroxyheme to iron-verdoheme in the presence of dioxygen. Dalton Trans 2018; 46:2146-2158. [PMID: 28120965 DOI: 10.1039/c6dt04250c] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Detailed insight into the second step of heme degradation by heme oxygenase, oxophlorin to verdoheme and biliverdin, is presented. Density functional theory methods are reported for the conversion of oxophlorin to verdoheme. Since it is currently unclear whether dioxygen binding to iron oxophlorin is followed by a reduction or not, in this work we have focused on the difference in reactivity between [(Im)(O2˙)FeIII(PO˙)] (PO˙ is the oxophlorin dianion radical) and [(Im)(O2˙)FeIII(PO)]- (PO is the oxophlorin trianion). Thus, we have shown that in [(Im)(O2˙)FeIII(PO˙)] and [(Im)(O2˙)FeIII(PO)]-, the mechanisms are stepwise with an initial C-O bond activation to form a ring-structure where the oxophlorin is distorted from planarity. This is followed by homolytic dioxygen bond breaking that directly leads to iron-oxo verdoheme products. The [(Im)(O2˙)FeIII(PO˙)] mechanism proceeds via two-state-reactivity patterns on the adjacent doublet and quartet spin state surfaces, whereas the [(Im)(O2˙)FeIII(PO)]- route shows single-state-reactivity on a triplet spin state surface. In both, the rate determining step is the C-O bond activation, with substantially lower barriers on the [(Im)(O2˙)FeIII(PO˙)] surface of 12.15 kcal mol-1 in the gas phase compared to 22.55 kcal mol-1 for the intermediate-spin of [(Im)(O2˙)FeIII(PO)]-. The complete active space self-consistent-field wave functions with second-order multi-reference perturbation theory were also studied. Finally, the effects of the solvent and the medium on the reaction barriers were tested and shown to be considerable.
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Affiliation(s)
- Mahin Gheidi
- Department of Chemistry, Faculty of Sciences, Shahid Beheshti University, G. C., Evin, 19839-63113, Tehran, Iran.
| | - Nasser Safari
- Department of Chemistry, Faculty of Sciences, Shahid Beheshti University, G. C., Evin, 19839-63113, Tehran, Iran.
| | - Mansour Zahedi
- Department of Chemistry, Faculty of Sciences, Shahid Beheshti University, G. C., Evin, 19839-63113, Tehran, Iran.
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44
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Cheng J, Wang L, Wang P, Deng L. High-Oxidation-State 3d Metal (Ti-Cu) Complexes with N-Heterocyclic Carbene Ligation. Chem Rev 2018; 118:9930-9987. [PMID: 30011189 DOI: 10.1021/acs.chemrev.8b00096] [Citation(s) in RCA: 116] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
High-oxidation-state 3d metal species have found a wide range of applications in modern synthetic chemistry and materials science. They are also implicated as key reactive species in biological reactions. These applications have thus prompted explorations of their formation, structure, and properties. While the traditional wisdom regarding these species was gained mainly from complexes supported by nitrogen- and oxygen-donor ligands, recent studies with N-heterocyclic carbenes (NHCs), which are widely used for the preparation of low-oxidation-state transition metal complexes in organometallic chemistry, have led to the preparation of a large variety of isolable high-oxidation-state 3d metal complexes with NHC ligation. Since the first report in this area in the 1990s, isolable complexes of this type have been reported for titanium(IV), vanadium(IV,V), chromium(IV,V), manganese(IV,V), iron(III,IV,V), cobalt(III,IV,V), nickel(IV), and copper(II). With the aim of providing an overview of this intriguing field, this Review summarizes our current understanding of the synthetic methods, structure and spectroscopic features, reactivity, and catalytic applications of high-oxidation-state 3d metal NHC complexes of titanium to copper. In addition to this progress, factors affecting the stability and reactivity of high-oxidation-state 3d metal NHC species are also presented, as well as perspectives on future efforts.
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Affiliation(s)
- Jun Cheng
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , People's Republic of China
| | - Lijun Wang
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , People's Republic of China
| | - Peng Wang
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , People's Republic of China
| | - Liang Deng
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , People's Republic of China
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45
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Tripathi A, Prabhakar C. Impact of replacement of the central benzene ring in anthracene by a heterocyclic ring on electronic excitations and reorganization energies in anthratetrathiophene molecules. J CHIN CHEM SOC-TAIP 2018. [DOI: 10.1002/jccs.201700448] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Anuj Tripathi
- Department of Chemistry; National Institute of Technology; Kurukshetra India
| | - Chetti Prabhakar
- Department of Chemistry; National Institute of Technology; Kurukshetra India
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46
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Mukherjee G, Lee CWZ, Nag SS, Alili A, Cantú Reinhard FG, Kumar D, Sastri CV, de Visser SP. Dramatic rate-enhancement of oxygen atom transfer by an iron(iv)-oxo species by equatorial ligand field perturbations. Dalton Trans 2018; 47:14945-14957. [DOI: 10.1039/c8dt02142b] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The reactivity and characterization of a novel iron(iv)-oxo species is reported that gives enhanced reactivity as a result of second-coordination sphere perturbations of the ligand system.
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Affiliation(s)
- Gourab Mukherjee
- Department of Chemistry
- Indian Institute of Technology Guwahati
- India
| | - Calvin W. Z. Lee
- The Manchester Institute of Biotechnology and the School of Chemical Engineering and Analytical Science
- The University of Manchester
- Manchester M1 7DN
- UK
| | | | - Aligulu Alili
- The Manchester Institute of Biotechnology and the School of Chemical Engineering and Analytical Science
- The University of Manchester
- Manchester M1 7DN
- UK
| | - Fabián G. Cantú Reinhard
- The Manchester Institute of Biotechnology and the School of Chemical Engineering and Analytical Science
- The University of Manchester
- Manchester M1 7DN
- UK
| | - Devesh Kumar
- Department of Applied Physics
- School for Physical Sciences
- Babasaheb Bhimrao Ambedkar University
- Lucknow 226025
- India
| | | | - Sam P. de Visser
- The Manchester Institute of Biotechnology and the School of Chemical Engineering and Analytical Science
- The University of Manchester
- Manchester M1 7DN
- UK
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47
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Kaczmarek MA, Malhotra A, Balan GA, Timmins A, de Visser SP. Nitrogen Reduction to Ammonia on a Biomimetic Mononuclear Iron Centre: Insights into the Nitrogenase Enzyme. Chemistry 2017; 24:5293-5302. [PMID: 29165842 PMCID: PMC5915742 DOI: 10.1002/chem.201704688] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Indexed: 11/05/2022]
Abstract
Nitrogenases catalyse nitrogen fixation to ammonia on a multinuclear Fe‐Mo centre, but their mechanism and particularly the order of proton and electron transfer processes that happen during the catalytic cycle is still unresolved. Recently, a unique biomimetic mononuclear iron model was developed using tris(phosphine)borate (TPB) ligands that was shown to convert N2 into NH3. Herein, we present a computational study on the [(TPB)FeN2]− complex and describe its conversion into ammonia through the addition of electrons and protons. In particular, we tested the consecutive proton transfer on only the distal nitrogen atom or alternated protonation of the distal/proximal nitrogen. It is found that the lowest energy pathway is consecutive addition of three protons to the same site, which forms ammonia and an iron‐nitrido complex. In addition, the proton transfer step of complexes with the metal in various oxidation and spin states were tested and show that the pKa values of biomimetic mononuclear nitrogenase intermediates vary little with iron oxidation states. As such, the model gives several possible NH3 formation pathways depending on the order of electron/proton transfer, and all should be physically accessible in the natural system. These results may have implications for enzymatic nitrogenases and give insight into the catalytic properties of mononuclear iron centres.
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Affiliation(s)
- Monika A Kaczmarek
- Manchester Institute of Biotechnology and School of Chemical, Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.,Department of Chemistry, University of Warsaw, Ludwika Pasteura 1, 02-093, Warsaw, Poland
| | - Abheek Malhotra
- Manchester Institute of Biotechnology and School of Chemical, Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
| | - G Alex Balan
- Manchester Institute of Biotechnology and School of Chemical, Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
| | - Amy Timmins
- Manchester Institute of Biotechnology and School of Chemical, Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
| | - Sam P de Visser
- Manchester Institute of Biotechnology and School of Chemical, Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
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48
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Cantú Reinhard FG, Barman P, Mukherjee G, Kumar J, Kumar D, Kumar D, Sastri CV, de Visser SP. Keto-Enol Tautomerization Triggers an Electrophilic Aldehyde Deformylation Reaction by a Nonheme Manganese(III)-Peroxo Complex. J Am Chem Soc 2017; 139:18328-18338. [PMID: 29148746 DOI: 10.1021/jacs.7b10033] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Oxygen atom transfer by high-valent enzymatic intermediates remains an enigma in chemical catalysis. In particular, manganese is an important first-row metal involved in key biochemical processes, including the biosynthesis of molecular oxygen (through the photosystem II complex) and biodegradation of toxic superoxide to hydrogen peroxide by superoxide dismutase. Biomimetic models of these biological systems have been developed to gain understanding on the structure and properties of short-lived intermediates but also with the aim to create environmentally benign oxidants. In this work, we report a combined spectroscopy, kinetics and computational study on aldehyde deformylation by two side-on manganese(III)-peroxo complexes with bispidine ligands. Both manganese(III)-peroxo complexes are characterized by UV-vis and mass spectrometry techniques, and their reactivity patterns with aldehydes was investigated. We find a novel mechanism for the reaction that is initiated by a hydrogen atom abstraction reaction, which enables a keto-enol tautomerization in the substrate. This is an essential step in the mechanism that makes an electrophilic attack on the olefin bond possible as the attack on the aldehyde carbonyl is too high in energy. Kinetics studies determine a large kinetic isotope effect for the replacement of the transferring hydrogen atom by deuterium, while replacing the transferring hydrogen atom by a methyl group makes the substrate inactive and hence confirm the hypothesized mechanism. Our new mechanism is confirmed with density functional theory modeling on the full mechanism and rationalized through valence bond and thermochemical cycles. Our unprecedented new mechanism may have relevance to biological and biomimetic chemistry processes in general and gives insight into the reactivity patterns of metal-peroxo and metal-hydroperoxo intermediates in general.
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Affiliation(s)
- Fabián G Cantú Reinhard
- The Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science, The University of Manchester , 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Prasenjit Barman
- Department of Chemistry, Indian Institute of Technology Guwahati 781039, Assam, India
| | - Gourab Mukherjee
- Department of Chemistry, Indian Institute of Technology Guwahati 781039, Assam, India
| | - Jitendra Kumar
- Department of Applied Physics, School for Physical Sciences, Babasaheb Bhimrao Ambedkar University , Lucknow 226025, UP, India
| | - Deep Kumar
- Department of Applied Physics, School for Physical Sciences, Babasaheb Bhimrao Ambedkar University , Lucknow 226025, UP, India
| | - Devesh Kumar
- Department of Applied Physics, School for Physical Sciences, Babasaheb Bhimrao Ambedkar University , Lucknow 226025, UP, India
| | - Chivukula V Sastri
- Department of Chemistry, Indian Institute of Technology Guwahati 781039, Assam, India
| | - Sam P de Visser
- The Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science, The University of Manchester , 131 Princess Street, Manchester M1 7DN, United Kingdom
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49
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Naskar S, Palmajumder E, Patra S, Mitra J, Mukherjea KK. Biomimicking Oxidative Bromination and DNA Nuclease Activities of a New Structurally Characterised Oxido-Diperoxidomolybdenum(VI) Complex. ChemistrySelect 2017. [DOI: 10.1002/slct.201701807] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Saurav Naskar
- Department of Chemistry; Jadavpur University; Kolkata - 700032 India
| | | | - Swarup Patra
- Department of Chemistry; Jadavpur University; Kolkata - 700032 India
| | - Joyee Mitra
- CSIR - Central Salt & Marine Chemicals Research Institute, Gijubhai Badheka Marg; Bhavnagar - 364 002, Gujarat India
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50
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Mallick D, Shaik S. Kinetic Isotope Effect Probes the Reactive Spin State, As Well As the Geometric Feature and Constitution of the Transition State during H-Abstraction by Heme Compound II Complexes. J Am Chem Soc 2017; 139:11451-11459. [PMID: 28737390 DOI: 10.1021/jacs.7b04247] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
What do experimentally measured kinetic isotope effects (KIEs) tell us about H-abstraction reactions with multispin-state reactivity options? Using DFT calculations with tunneling corrections for experimentally studied H-abstraction reactions of porphyrin-Compound II species (Chem.-Eur. J. 2014, 20, 14437; Angew. Chem., Int. Ed. 2008, 47, 7321) with cyclohexane, dihydroanthracene (DHA), and xanthene (Xan), we show here that KIE is a selective probe that identifies the experimentally reactive spin state. At the same time, comparison of calculated and experimental KIE values permits us to determine the structural orientation of the transition states, as well as the presence/absence of an axial ligand, and the effect of porphyrin substituents. The studied compound II (Cpd II) species involve porphine, and porphyrin ligands with different meso-substituents, TPFPP (tetrakis(pentafluorophenyl)porphyrin dianion) and TMP (tetramesitylporphyrin dianion), with and without imidazole axial ligands. The DFT calculations reveal three potential pathways: quintet and triplet σ-pathways (5Hσ and 3Hσ) that possess linear transition state (TS) structures, and a triplet π -pathway (3Hπ) having a bent TS structure. Without an axial ligand, the 5Hσ pathways for these Cpd II complexes cross below the triplet states. The axial ligand raises the barriers for the quintet and triplet σ-pathways and quenches any chances for two-state reactivity, thus proceeding via the 3Hπ pathway. All of these pathways exhibit characteristic KIE values: very large for 3Hπ (48-200), small for 5Hσ (3-9), and intermediate for 3Hσ (23-51). The calculated KIEs for (TPFPP)FeIV═O without an axial ligand reveal that 3Hσ is the only pathway having a KIE that matches the experimental values, for the reactions with DHA and Xan (Angew. Chem., Int. Ed. 2008, 47, 7321). Indeed, theory shows that tunneling significantly lowers the 3Hσ barrier rendering it the sole reactive state for the reaction. A prediction is made for the reactivity and KIE of (TMP)FeIV═O complex, and a comparison is made with the analogous nonheme complexes.
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Affiliation(s)
- Dibyendu Mallick
- Institute of Chemistry and the Lise Meitner Minerva Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem , Jerusalem 91904, Israel
| | - Sason Shaik
- Institute of Chemistry and the Lise Meitner Minerva Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem , Jerusalem 91904, Israel
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