1
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Kumar M, Gupta MK, Ansari M, Ansari A. C-H bond activation by high-valent iron/cobalt-oxo complexes: a quantum chemical modeling approach. Phys Chem Chem Phys 2024; 26:4349-4362. [PMID: 38235511 DOI: 10.1039/d3cp05866b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
High-valent metal-oxo species serve as key intermediates in the activation of inert C-H bonds. Here, we present a comprehensive DFT analysis of the parameters that have been proposed as influencing factors in modeled high-valent metal-oxo mediated C-H activation reactions. Our approach involves utilizing DFT calculations to explore the electronic structures of modeled FeIVO (species 1) and CoIVO ↔ CoIII-O˙ (species 2), scrutinizing their capacity to predict improved catalytic activity. DFT and DLPNO-CCSD(T) calculations predict that the iron-oxo species possesses a triplet as the ground state, while the cobalt-oxo has a doublet as the ground state. Furthermore, we have investigated the mechanistic pathways for the first C-H bond activation, as well as the desaturation of the alkanes. The mechanism was determined to be a two-step process, wherein the first hydrogen atom abstraction (HAA) represents the rate-limiting step, involving the proton-coupled electron transfer (PCET) process. However, we found that the second HAA step is highly exothermic for both species. Our calculations suggest that the iron-oxo species (Fe-O = 1.672 Å) exhibit relatively sluggish behavior compared to the cobalt-oxo species (Co-O = 1.854 Å) in C-H bond activation, attributed to a weak metal-oxygen bond. MO, NBO, and deformation energy analysis reveal the importance of weakening the M-O bond in the cobalt species, thereby reducing the overall barrier to the reaction. This catalyst was found to have a C-H activation barrier relatively smaller than that previously reported in the literature.
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Affiliation(s)
- Manjeet Kumar
- Department of Chemistry, Central University of Haryana, Mahendergarh-123031, Haryana, India.
| | - Manoj Kumar Gupta
- Department of Chemistry, Central University of Haryana, Mahendergarh-123031, Haryana, India.
| | - Mursaleem Ansari
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
| | - Azaj Ansari
- Department of Chemistry, Central University of Haryana, Mahendergarh-123031, Haryana, India.
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2
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Wang D, Ingram AA, Okumura A, Spaniol TP, Schwaneberg U, Okuda J. Benzylic C(sp 3 )-H Bond Oxidation with Ketone Selectivity by a Cobalt(IV)-Oxo Embedded in a β-Barrel Protein. Chemistry 2024; 30:e202303066. [PMID: 37818668 DOI: 10.1002/chem.202303066] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 10/10/2023] [Accepted: 10/11/2023] [Indexed: 10/12/2023]
Abstract
Artificial metalloenzymes have emerged as biohybrid catalysts that allow to combine the reactivity of a metal catalyst with the flexibility of protein scaffolds. This work reports the artificial metalloenzymes based on the β-barrel protein nitrobindin NB4, in which a cofactor [CoII X(Me3 TACD-Mal)]+ X- (X=Cl, Br; Me3 TACD=N,N' ,N''-trimethyl-1,4,7,10-tetraazacyclododecane, Mal=CH2 CH2 CH2 NC4 H2 O2 ) was covalently anchored via a Michael addition reaction. These biohybrid catalysts showed higher efficiency than the free cobalt complexes for the oxidation of benzylic C(sp3 )-H bonds in aqueous media. Using commercially available oxone (2KHSO5 ⋅ KHSO4 ⋅ K2 SO4 ) as oxidant, a total turnover number of up to 220 and 97 % ketone selectivity were achieved for tetralin. As catalytically active intermediate, a mononuclear terminal cobalt(IV)-oxo species [Co(IV)=O]2+ was generated by reacting the cobalt(II) cofactor with oxone in aqueous solution and characterized by ESI-TOF MS.
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Affiliation(s)
- Dong Wang
- Institute of Inorganic Chemistry, RWTH Aachen University, 52074, Aachen, Germany
| | - Aaron A Ingram
- Institute of Inorganic Chemistry, RWTH Aachen University, 52074, Aachen, Germany
| | - Akira Okumura
- Institute of Inorganic Chemistry, RWTH Aachen University, 52074, Aachen, Germany
| | - Thomas P Spaniol
- Institute of Inorganic Chemistry, RWTH Aachen University, 52074, Aachen, Germany
| | - Ulrich Schwaneberg
- Institute of Biotechnology, RWTH Aachen University, 52074, Aachen, Germany
| | - Jun Okuda
- Institute of Inorganic Chemistry, RWTH Aachen University, 52074, Aachen, Germany
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3
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Son Y, Jeong D, Kim K, Cho J. Mechanistic Insights into Nitrile Activation by Cobalt(III)-Hydroperoxo Intermediates: The Influence of Ligand Basicity. JACS AU 2023; 3:3204-3212. [PMID: 38034966 PMCID: PMC10685436 DOI: 10.1021/jacsau.3c00532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 10/06/2023] [Accepted: 10/09/2023] [Indexed: 12/02/2023]
Abstract
The versatile applications of nitrile have led to the widespread use of nitrile activation in the synthesis of pharmacologically and industrially valuable compounds. We reported the activation of nitriles using mononuclear cobalt(III)-hydroperoxo complexes, [CoIII(Me3-TPADP)(O2H)(RCN)]2+ [R = Me (2) and Ph (2Ph)], to form cobalt(III)-peroxyimidato complexes, [CoIII(Me3-TPADP)(R-C(=NH)O2)]2+ [R = Me (3) and Ph (3Ph)]. The independence of the rate on the nitrile concentration and the positive Hammett value of 3.2(2) indicated that the reactions occur via an intramolecular nucleophilic attack of the hydroperoxide ligand to the coordinated nitrile carbon atom. In contrast, the previously reported cobalt(III)-hydroperoxo complex, [CoIII(TBDAP)(O2H)(CH3CN)]2+ (2TBDAP), exhibited the deficiency of reactivity toward nitrile. The comparison of pKa values and redox potentials of 2 and 2TBDAP showed that Me3-TPADP had a stronger ligand field strength than that of TBDAP. The density functional theory calculations for 2 and 2TBDAP support that the strengthened ligand field in 2 is mainly due to the replacement of two tert-butyl amine donors in TBDAP with methyl groups in Me3-TPADP, resulting in the compression of the Co-Nax bond lengths. These results provide mechanistic evidence of nitrile activation by the cobalt(III)-hydroperoxo complex and indicate that the basicity dependent on the ligand framework contributes to the ability of nitrile activation.
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Affiliation(s)
- Yeongjin Son
- Department
of Chemistry, Ulsan National Institute of
Science and Technology (UNIST), Ulsan 44919, Republic of Korea
- Department
of Emerging Materials Science, Daegu Gyeongbuk
Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - Donghyun Jeong
- Department
of Chemistry, Ulsan National Institute of
Science and Technology (UNIST), Ulsan 44919, Republic of Korea
| | - Kyungmin Kim
- Department
of Chemistry, Ulsan National Institute of
Science and Technology (UNIST), Ulsan 44919, Republic of Korea
- Department
of Emerging Materials Science, Daegu Gyeongbuk
Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - Jaeheung Cho
- Department
of Chemistry, Ulsan National Institute of
Science and Technology (UNIST), Ulsan 44919, Republic of Korea
- Graduate
School of Carbon Neutrality, Ulsan National
Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
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4
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Lesnikov VK, Golovanov IS, Nelyubina YV, Aksenova SA, Sukhorukov AY. Crown-hydroxylamines are pH-dependent chelating N,O-ligands with a potential for aerobic oxidation catalysis. Nat Commun 2023; 14:7673. [PMID: 37996433 PMCID: PMC10667252 DOI: 10.1038/s41467-023-43530-6] [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: 07/06/2023] [Accepted: 11/13/2023] [Indexed: 11/25/2023] Open
Abstract
Despite the rich coordination chemistry, hydroxylamines are rarely used as ligands for transition metal coordination compounds. This is partially because of the instability of these complexes that undergo decomposition, disproportionation and oxidation processes involving the hydroxylamine motif. Here, we design macrocyclic poly-N-hydroxylamines (crown-hydroxylamines) that form complexes containing a d-metal ion (Cu(II), Ni(II), Mn(II), and Zn(II)) coordinated by multiple (up to six) hydroxylamine fragments. The stability of these complexes is likely to be due to a macrocycle effect and strong intramolecular H-bonding interactions between the N-OH groups. Crown-hydroxylamine complexes exhibit interesting pH-dependent behavior where the efficiency of metal binding increases upon deprotonation of the hydroxylamine groups. Copper complexes exhibit catalytic activity in aerobic oxidation reactions under ambient conditions, whereas the corresponding complexes with macrocyclic polyamines show poor or no activity. Our results show that crown-hydroxylamines display anomalous structural features and chemical behavior with respect to both organic hydroxylamines and polyaza-crowns.
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Affiliation(s)
- Vladislav K Lesnikov
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 119991, Leninsky prospect, 47, Moscow, Russian Federation
| | - Ivan S Golovanov
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 119991, Leninsky prospect, 47, Moscow, Russian Federation
| | - Yulia V Nelyubina
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, 119991, Vavilova str. 28, Moscow, Russian Federation
- Moscow Institute of Physics and Technology (National Research University), 141700, Institutskiy per. 9, Dolgoprudny, Moscow Region, Russian Federation
| | - Svetlana A Aksenova
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, 119991, Vavilova str. 28, Moscow, Russian Federation
- Moscow Institute of Physics and Technology (National Research University), 141700, Institutskiy per. 9, Dolgoprudny, Moscow Region, Russian Federation
| | - Alexey Yu Sukhorukov
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 119991, Leninsky prospect, 47, Moscow, Russian Federation.
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5
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Samanta B, Ghosh R, Mazumdar R, Saha S, Maity S, Mondal B. Reaction of a Co(III)-peroxo complex with nitric oxide: putative formation of a peroxynitrite intermediate. Dalton Trans 2023; 52:15815-15821. [PMID: 37815553 DOI: 10.1039/d3dt02261g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/11/2023]
Abstract
A Co(II) complex, [CoII(L)2(H2O)2](ClO4)2, 1, having a bidentate ligand L [L = bis(3,5-dimethylpyrazolyl)methane] has been synthesized. Complex 1 in acetonitrile solution at -40 °C, in the presence of H2O2 and NEt3, afforded the corresponding Co(III)-peroxo species, [CoIII(L)2(O22-)]+, as the transient intermediate 1a. Thermal instability precluded its isolation and further characterization. The addition of nitric oxide (NO) gas into the freshly prepared [CoIII(L)2(O22-)]+ in acetonitrile at -40 °C resulted in the corresponding Co(II)-nitrato complex, [CoII(L)2(NO3)](ClO4) (2). The reaction is proposed to proceed through a putative Co(II)-peroxynitrite intermediate 1b. It was evidenced by the characteristic phenol ring nitration reaction.
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Affiliation(s)
- Bapan Samanta
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India.
| | - Riya Ghosh
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India.
| | - Rakesh Mazumdar
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India.
| | - Shankhadeep Saha
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India.
| | - Sayani Maity
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India.
| | - Biplab Mondal
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India.
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6
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Deolka S, Govindarajan R, Khaskin E, Vasylevskyi S, Bahri J, Fayzullin RR, Roy MC, Khusnutdinova JR. Oxygen transfer reactivity mediated by nickel perfluoroalkyl complexes using molecular oxygen as a terminal oxidant. Chem Sci 2023; 14:7026-7035. [PMID: 37389265 PMCID: PMC10306096 DOI: 10.1039/d3sc01861j] [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: 04/10/2023] [Accepted: 06/03/2023] [Indexed: 07/01/2023] Open
Abstract
Nickel perfluoroethyl and perfluoropropyl complexes supported by naphthyridine-type ligands show drastically different aerobic reactivity from their trifluoromethyl analogs resulting in facile oxygen transfer to perfluoroalkyl groups or oxygenation of external organic substrates (phosphines, sulfides, alkenes and alcohols) using O2 or air as a terminal oxidant. Such mild aerobic oxygenation occurs through the formation of spectroscopically detected transient high-valent NiIII and structurally characterized mixed-valent NiII-NiIV intermediates and radical intermediates, resembling O2 activation reported for some Pd dialkyl complexes. This reactivity is in contrast with the aerobic oxidation of naphthyridine-based Ni(CF3)2 complexes resulting in the formation of a stable NiIII product, which is attributed to the effect of greater steric congestion imposed by longer perfluoroalkyl chains.
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Affiliation(s)
- Shubham Deolka
- Coordination Chemistry and Catalysis Unit Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha Onna-son 904-0495 Okinawa Japan
| | - R Govindarajan
- Coordination Chemistry and Catalysis Unit Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha Onna-son 904-0495 Okinawa Japan
| | - Eugene Khaskin
- Coordination Chemistry and Catalysis Unit Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha Onna-son 904-0495 Okinawa Japan
| | - Serhii Vasylevskyi
- Coordination Chemistry and Catalysis Unit Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha Onna-son 904-0495 Okinawa Japan
| | - Janet Bahri
- Coordination Chemistry and Catalysis Unit Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha Onna-son 904-0495 Okinawa Japan
| | - Robert R Fayzullin
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences 8 Arbuzov Street Kazan 420088 Russian Federation
| | - Michael C Roy
- Coordination Chemistry and Catalysis Unit Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha Onna-son 904-0495 Okinawa Japan
| | - Julia R Khusnutdinova
- Coordination Chemistry and Catalysis Unit Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha Onna-son 904-0495 Okinawa Japan
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7
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Jeong D, Selverstone Valentine J, Cho J. Bio-inspired mononuclear nonheme metal peroxo complexes: Synthesis, structures and mechanistic studies toward understanding enzymatic reactions. Coord Chem Rev 2023. [DOI: 10.1016/j.ccr.2023.215021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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8
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Zhang J, Li S, Fang H. C-H bond activations by the HO˙/(Salophen t-Bu)Co(II) radical pair generated via homolysis of a terminal Co(III)-OH bond. Chem Commun (Camb) 2023; 59:3245-3248. [PMID: 36815508 DOI: 10.1039/d3cc00146f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
The reactive HO˙/(Salophent-Bu)Co(II) radical pair was observed to be generated via homolysis of the terminal Co(III)-OH bond in transient (Salophent-Bu)(L)Co(III)(OH) (L = Py, MeOH) complexes as indicated by UV-Vis and EPR measurements. Based on this elementary process, C-H bond activations in acetone, 2-butanone, acetonitrile and benzene were achieved under ambient conditions. For the reactions of the first three substrates, the alkylcobalt(III) complexes were formed as the products.
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Affiliation(s)
- Jia Zhang
- School of Materials Science and Engineering, Tianjin Key Lab for Rare Earth Materials and Applications, Nankai University, Tianjin, 300350, China.
| | - Songyi Li
- School of Materials Science and Engineering, Tianjin Key Lab for Rare Earth Materials and Applications, Nankai University, Tianjin, 300350, China.
| | - Huayi Fang
- School of Materials Science and Engineering, Tianjin Key Lab for Rare Earth Materials and Applications, Nankai University, Tianjin, 300350, China.
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9
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Gordon JB, Albert T, Yadav S, Thomas J, Siegler MA, Moënne-Loccoz P, Goldberg DP. Oxygen versus Sulfur Coordination in Cobalt Superoxo Complexes: Spectroscopic Properties, O 2 Binding, and H-Atom Abstraction Reactivity. Inorg Chem 2023; 62:392-400. [PMID: 36538786 PMCID: PMC10194424 DOI: 10.1021/acs.inorgchem.2c03484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A five-coordinate, disiloxide-ligated cobalt(II) (S = 3/2) complex (1) was prepared as an oxygen-ligated analogue to the previously reported silanedithiolate-ligated CoII(Me3TACN)(S2SiMe2) (J. Am. Chem. Soc., 2019, 141, 3641-3653). The structural and spectroscopic properties of 1 were analyzed by single-crystal X-ray diffraction, electron paramagnetic resonance (EPR), and NMR spectroscopies. The reactivity of 1 with dioxygen was examined, and it was shown to bind O2 reversibly in a range of solvents at low temperatures. A cobalt(III)-superoxo complex, CoIII(O2·-)(Me3TACN)((OSi2Ph)2O) (2), was generated, and was analyzed by UV-vis, EPR, and resonance Raman spectroscopies. Unlike its sulfur-ligated analogue, complex 2 can thermally release O2 to regenerate 1. Vibrational assignments for selective 18O isotopic labeling of both O2 and disiloxide ligands in 2 are consistent with a 6-coordinate, Co(η1-O2·-)("end-on") complex. Complex 2 reacts with the O-H bond of 4-methoxy-2,2,6,6-tetramethylpiperidin-1-ol (4-MeO-TEMPOH) via H-atom abstraction with a rate of 0.58(2) M-1 s-1 at -105 °C, but it is unable to oxidize phenol substrates. This bracketed reactivity suggests that the O-H bond being formed in the putative CoIII(OOH) product has a relatively weak O-H bond strength (BDFE ∼66-74 kcal mol-1). These thermodynamic and kinetic parameters are similar to those seen for the sulfur-ligated Co(O2)(Me3TACN)(S2SiMe2), indicating that the differences in the electronic structure for O versus S ligation do not have a large impact on H-atom abstraction reactivity.
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Affiliation(s)
- Jesse B Gordon
- Department of Chemistry, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, United States
| | - Therese Albert
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, Oregon 97239, United States
| | - Sudha Yadav
- Department of Chemistry, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, United States
| | - Jithin Thomas
- Department of Chemistry, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, United States
| | - Maxime A Siegler
- Department of Chemistry, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, United States
| | - Pierre Moënne-Loccoz
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, Oregon 97239, United States
| | - David P Goldberg
- Department of Chemistry, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, United States
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10
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Monika, Ansari A. Effect of the ring size of TMC ligands in controlling C-H bond activation by metal-superoxo species. Dalton Trans 2022; 51:5878-5889. [PMID: 35347335 DOI: 10.1039/d2dt00491g] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Metal-superoxo species play a very important role in many metal-mediated catalytic transformation reactions. Their catalytic reactivity is affected by many factors such as the nature of metal ions and ring size of ligands. Herein, for the first time, we report DFT calculations on the electronic structures of a series of metal-superoxo species (M = V, Cr, Mn, Fe, and Co) with two ring size ligands, i.e., 13-TMC/14-TMC, and a detailed mechanistic study on the C-H bond activation of cyclohexa-1,4-diene followed by the effect of the ring size of ligands. Our DFT results showed that the electron density at the distal oxygen plays an important role in C-H bond activation. By computing the energetics of C-H bond activation and mapping the potential energy surface, it was found that the initial hydrogen abstraction is the rate-determining step with both TMC rings and all the studied metal-superoxo species. The significant electron density at the cyclohex-1,4-diene carbon indicates that the reaction proceeds via the proton-coupled electron transfer mechanism. By mapping the potential energy surfaces, we found that the 13-TMC ligated superoxo with the anti-isomer are more reactive than the 14-TMC superoxo species except for the iron-superoxo species where the 14-TMC ligated superoxo species is more reactive i.e. smaller ring size TMC is more reactive towards C-H bond activation. This is also supported by the structural correlation, i.e., the greater contraction in the smaller ring results in the metal being pushed out of plane along the z-axis, which reduces the steric hindrance. Thus, the ring size can help in designing catalysts with better efficiency for catalytic reactions.
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Affiliation(s)
- Monika
- Department of Chemistry, Central University of Haryana, India, 123031.
| | - Azaj Ansari
- Department of Chemistry, Central University of Haryana, India, 123031.
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11
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Zhou A, Cao X, Chen H, Sun D, Zhao Y, Nam W, Wang Y. The chameleon-like nature of elusive cobalt-oxygen intermediates in C-H bond activation reactions. Dalton Trans 2022; 51:4317-4323. [PMID: 35212349 DOI: 10.1039/d2dt00224h] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
High-valence metal-oxo (M-O, M = Fe, Mn, etc.) species are well-known reaction intermediates that are responsible for a wide range of pivotal oxygenation reactions and water oxidation reactions in metalloenzymes. Although extensive efforts have been devoted to synthesizing and identifying such complexes in biomimetic studies, the structure-function relationship and related reaction mechanisms of these reaction intermediates remain elusive, especially for the cobalt-oxygen species. In the present manuscript, the calculated results demonstrate that the tetraamido macrocycle ligated cobalt complex, Co(O)(TAML) (1), behaves like a chameleon: the electronic structure varies from a cobalt(III)-oxyl species to a cobalt(IV)-oxo species when a Lewis acid Sc3+ salt coordinates or an acidic hydrocarbon attacks 1. The dichotomous correlation between the reaction rates of C-H bond activation by 1 and the bond dissociation energy (BDE) vs. the acidity (pKa) was rationalized for the first time by different reaction mechanisms: for normal C-H bond activation, the Co(III)-oxyl species directly activates the C-H bond via a hydrogen atom transfer (HAT) mechanism, whereas for acidic C-H bond activation, the Co(III)-oxyl species evolves to a Co(IV)-oxo species to increase the basicity of the oxygen to activate the acidic C-H bond, via a novel PCET(PT) mechanism (proton-coupled electron transfer with a PT(proton-transfer)-like transition state). These theoretical findings will enrich the knowledge of biomimetic metal-oxygen chemistry.
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Affiliation(s)
- Anran Zhou
- Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, China. .,Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo 315211, China
| | - Xuanyu Cao
- Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, China. .,Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo 315211, China
| | - Huanhuan Chen
- Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, China. .,Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo 315211, China
| | - Dongru Sun
- Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, China. .,Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo 315211, China
| | - Yufen Zhao
- Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, China. .,Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo 315211, China
| | - Wonwoo Nam
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea.
| | - Yong Wang
- Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, China. .,Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo 315211, China
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12
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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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13
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Ghosh I, Chakraborty B, Bera A, Paul S, Paine TK. Selective oxygenation of C-H and CC bonds with H 2O 2 by high-spin cobalt(II)-carboxylate complexes. Dalton Trans 2022; 51:2480-2492. [PMID: 35050271 DOI: 10.1039/d1dt02235k] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Four cobalt(II)-carboxylate complexes [(6-Me3-TPA)CoII(benzoate)](BPh4) (1), [(6-Me3-TPA)CoII(benzilate)](ClO4) (2), [(6-Me3-TPA)CoII(mandelate)](BPh4) (3), and [(6-Me3-TPA)CoII(MPA)](BPh4) (4) (HMPA = 2-methoxy-2-phenylacetic acid) of the 6-Me3-TPA (tris((6-methylpyridin-2-yl)methyl)amine) ligand were isolated to investigate their ability in H2O2-dependent selective oxygenation of C-H and CC bonds. All six-coordinate complexes contain a high-spin cobalt(II) center. While the cobalt(II) complexes are inert toward dioxygen, each of these complexes reacts readily with hydrogen peroxide to form a diamagnetic cobalt(III) species, which decays with time leading to the oxidation of the methyl groups on the pyridine rings of the supporting ligand. Intramolecular ligand oxidation by the cobalt-based oxidant is partially inhibited in the presence of external substrates, and the substrates are converted to their corresponding oxidized products. Kinetic studies and labelling experiments indicate the involvement of a metal-based oxidant in affecting the chemo- and stereo-selective catalytic oxygenation of aliphatic C-H bonds and epoxidation of alkenes. An electrophilic cobalt-oxygen species that exhibits a kinetic isotope effect (KIE) value of 5.3 in toluene oxidation by 1 is proposed as the active oxidant. Among the complexes, the cobalt(II)-benzoate (1) and cobalt(II)-MPA (4) complexes display better catalytic activity compared to their α-hydroxy analogues (2 and 3). Catalytic studies with the cobalt(II)-acetonitrile complex [(6-Me3-TPA)CoII(CH3CN)2](ClO4)2 (5) in the presence and absence of externally added benzoate support the role of the carboxylate co-ligand in oxidation reactions. The proposed catalytic reaction involves a carboxylate-bridged dicobalt complex in the activation of H2O2 followed by the oxidation of substrates by a metal-based oxidant.
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Affiliation(s)
- Ivy Ghosh
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, India.
| | - Biswarup Chakraborty
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, India.
| | - Abhijit Bera
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, India.
| | - Satadal Paul
- Department of Chemistry, Bangabasi Morning College, 19, Rajkumar Chakraborty Sarani, Kolkata - 700 009, India
| | - Tapan Kanti Paine
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, India.
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14
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Zhao N, Filatov AS, Xie J, Hill EA, Rogachev AY, Anderson JS. Generation and Reactivity of a Ni III2(μ-1,2-peroxo) Complex. J Am Chem Soc 2020; 142:21634-21639. [PMID: 33320644 DOI: 10.1021/jacs.0c10958] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
High-valent transition metal-oxo, -peroxo, and -superoxo complexes are crucial intermediates in both biological and synthetic oxidation of organic substrates, water oxidation, and oxygen reduction. While high-valent oxygenated complexes of Mn, Fe, Co, and Cu are increasingly well-known, high-valent oxygenated Ni complexes are comparatively rarer. Herein we report the isolation of such an unusual high-valent species in a thermally unstable NiIII2(μ-1,2-peroxo) complex, which has been characterized using single-crystal X-ray diffraction and X-ray absorption, NMR, and UV-vis spectroscopies. Reactivity studies show that this complex is stable toward dissociation of oxygen but reacts with simple nucleophiles and electrophiles.
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Affiliation(s)
- Norman Zhao
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Alexander S Filatov
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Jiaze Xie
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Ethan A Hill
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Andrey Yu Rogachev
- Department of Chemistry, Illinois Institute of Technology, Chicago, Illinois 60616, United States
| | - John S Anderson
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
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15
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Anjana SS, Varghese B, Murthy NN. Coligand modulated oxidative O-demethylation of a methyl ether appended tetradentate N-ligand in Co(ii) complexes. Dalton Trans 2020; 49:3187-3197. [PMID: 31967148 DOI: 10.1039/c9dt04609g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Two Co(ii) complexes of the formula CoLOMeX2 (X = Cl- (1a); X = I- (1b)), where LOMe is 2-methoxy-N,N-bis(pyridin-2-ylmethyl) aniline, were synthesized and their structure, spectra and reactivity were studied. Upon oxidation of 1a and 1b, the ligand LOMe undergoes demethylation at the metal centre resulting in the formation of Co(iii) complexes with modified phenoxide ligands. This is the very first example of oxidative O-demethylation reported at a Co(ii) centre. The oxidative behaviour exhibits a striking dependence on the nature of coligands coordinated to the metal centre. The Co(ii) complex 1a with stronger chloro coligands requires a strong oxidising agent like t-BuOOH for oxidative demethylation and the subsequent formation of a mononuclear Co(iii) complex with a demethylated ligand, CoLO-Cl2 (2). On the other hand, complex 1b with weaker iodo coligands undergoes oxidation in the presence of the weak oxidant O2 to form a dihydroxo bridged binuclear Co(iii) complex [Co2(LO-)2(OH)2]2+ (3) with modified phenoxide ligands. The oxidation of 1b to 3 is monitored and the intermediate Co(ii) iodo aqua complex [CoLOMeI(H2O)]+ and Co(ii) diaqua complex [CoLOMe(H2O)2]2+ are isolated and characterised.
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Affiliation(s)
- S S Anjana
- Department of Chemistry, IIT Madras, Chennai 600 036, India.
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16
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Anandababu K, Muthuramalingam S, Velusamy M, Mayilmurugan R. Single-step benzene hydroxylation by cobalt(ii) catalysts via a cobalt(iii)-hydroperoxo intermediate. Catal Sci Technol 2020. [DOI: 10.1039/c9cy02601k] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Cobalt(ii) complexes reported as efficient and selective catalysts for single-step phenol formation from benzene using H2O2. The catalysis proceeds likely via cobalt(iii)-hydroperoxo species.
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Affiliation(s)
- Karunanithi Anandababu
- Bioinorganic Chemistry Laboratory/Physical Chemistry
- School of Chemistry
- Madurai Kamaraj University
- Madurai-625021
- India
| | - Sethuraman Muthuramalingam
- Bioinorganic Chemistry Laboratory/Physical Chemistry
- School of Chemistry
- Madurai Kamaraj University
- Madurai-625021
- India
| | - Marappan Velusamy
- Department of Chemistry
- North Eastern Hill University
- Shillong-793022
- India
| | - Ramasamy Mayilmurugan
- Bioinorganic Chemistry Laboratory/Physical Chemistry
- School of Chemistry
- Madurai Kamaraj University
- Madurai-625021
- India
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17
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Marino T, Fortino MG, Russo N, Toscano M, Alberto ME. Computational Mechanistic Insights on the NO Oxidation Reaction Catalyzed by Non-Heme Biomimetic Cr-N-Tetramethylated Cyclam Complexes. Int J Mol Sci 2019; 20:ijms20163955. [PMID: 31416223 PMCID: PMC6721035 DOI: 10.3390/ijms20163955] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 07/31/2019] [Accepted: 08/08/2019] [Indexed: 12/16/2022] Open
Abstract
The conversion reaction of NO to NO3− ion catalyzed by the end-on [Cr(III)(n-TMC)(O2)(Cl)]+ superoxo and side-on [Cr(IV)(n-TMC)(O2)(Cl)]+ peroxo non-heme complexes (n = 12, 13, 14 and 15), which are biomimetic systems of nitric oxide dioxygenases (NODs), has been explored using a computational protocol in the framework of density functional theory. Results show that the potential energy profiles for the studied reactions lie above the reagent energies, regardless of the used catalyst. Both the O-O bond breaking in the biomimetics and the NO3− ion formation require low energy barriers suggesting an efficient catalytic power of the studied systems. The rate-determining step depends on ligand size.
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Affiliation(s)
- Tiziana Marino
- Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, 87036 Rende, Italy.
| | - Maria Grazia Fortino
- Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, 87036 Rende, Italy
| | - Nino Russo
- Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, 87036 Rende, Italy.
| | - Marirosa Toscano
- Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, 87036 Rende, Italy
| | - Marta Erminia Alberto
- Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, 87036 Rende, Italy
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18
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Lee CM, Sankaralingam M, Chuo CH, Tseng TH, Chen PPY, Chiang MH, Li XX, Lee YM, Nam W. A Mn(iv)-peroxo complex in the reactions with proton donors. Dalton Trans 2019; 48:5203-5213. [PMID: 30941378 DOI: 10.1039/c9dt00649d] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Protons play an important role in promoting O-O or M-O bond cleavage of metal-peroxo complexes. Treatment of side-on O2-bound [PPN][MnIV(TMSPS3)(O2)] (1, PPN = bis(triphenylphosphine)iminium and TMSPS3H3 = 2,2',2''-trimercapto-3,3',3''-tris(trimethylsilyl)triphenylphosphine) with perchloric acid (HClO4) in the presence of PR3 (R = phenyl or p-tolyl) results in the formation of neutral five-coordinate MnIII(OPR3)(TMSPS3) complexes (R = phenyl, 2a; p-tolyl, 2b), which are confirmed by X-ray crystallography. Isotope labelling experiments demonstrate that the oxygen atom in the phosphine oxide product derives from the peroxo ligand of 1. Reactions of 1 with weak proton donors, such as phenylthiol, phenol, substituted phenol and methanol, are also investigated to explore the reactivity of the MnIV-peroxo complex, leading to the isolation of a series of five-coordinate [MnIII(L)(TMSPS3)]- complexes (L = phenylthiolate, phenolate or methoxide). Mechanistic aspects of the reactions of the MnIV-peroxo complex with proton donors are discussed as well.
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Affiliation(s)
- Chien-Ming Lee
- Department of Applied Science, National Taitung University, Jhihben Campus: 369, Sec. 2, University Rd., Taitung 950, Taiwan.
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19
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Gordon JB, Vilbert AC, Siegler MA, Lancaster KM, Moënne-Loccoz P, Goldberg DP. A Nonheme Thiolate-Ligated Cobalt Superoxo Complex: Synthesis and Spectroscopic Characterization, Computational Studies, and Hydrogen Atom Abstraction Reactivity. J Am Chem Soc 2019; 141:3641-3653. [PMID: 30776222 DOI: 10.1021/jacs.8b13134] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The synthesis and characterization of a Co(II) dithiolato complex Co(Me3TACN)(S2SiMe2) (1) are reported. Reaction of 1 with O2 generates a rare thiolate-ligated cobalt-superoxo species Co(O2)(Me3TACN)(S2SiMe2) (2) that was characterized spectroscopically and structurally by resonance Raman, EPR, and X-ray absorption spectroscopies as well as density functional theory. Metal-superoxo species are proposed to S-oxygenate metal-bound thiolate donors in nonheme thiol dioxygenases, but 2 does not lead to S-oxygenation of the intramolecular thiolate donors and does not react with exogenous sulfur donors. However, complex 2 is capable of oxidizing the O-H bonds of 2,2,6,6-tetramethylpiperidin-1-ol derivatives via H atom abstraction. Complementary proton-coupled electron-transfer reactivity is seen for 2 with separated proton/reductant pairs. The reactivity studies indicate that 2 can abstract H atoms from weak X-H bonds with bond dissociation free energy (BDFE) ≤ 70 kcal mol-1. DFT calculations predict that the putative Co(OOH) product has an O-H BDFE = 67 kcal mol-1, which matches the observed pattern of reactivity seen for 2. These data provide new information regarding the selectivity of S-oxygenation versus H atom abstraction in thiolate-ligated nonheme metalloenzymes that react with O2.
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Affiliation(s)
- Jesse B Gordon
- Department of Chemistry , The Johns Hopkins University , 3400 North Charles Street , Baltimore , Maryland 21218 , United States
| | - Avery C Vilbert
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853 , United States
| | - Maxime A Siegler
- Department of Chemistry , The Johns Hopkins University , 3400 North Charles Street , Baltimore , Maryland 21218 , United States
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853 , United States
| | - Pierre Moënne-Loccoz
- Department of Biochemistry & Molecular Biology , Oregon Health & Science University , Portland , Oregon 97239-3098 , United States
| | - David P Goldberg
- Department of Chemistry , The Johns Hopkins University , 3400 North Charles Street , Baltimore , Maryland 21218 , United States
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20
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Nishiura T, Chiba Y, Nakazawa J, Hikichi S. Tuning the O2 Binding Affinity of Cobalt(II) Centers by Changing the Structural and Electronic Properties of the Distal Substituents on Azole-Based Chelating Ligands. Inorg Chem 2018; 57:14218-14229. [DOI: 10.1021/acs.inorgchem.8b02241] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Toshiki Nishiura
- Department of Material and Life Chemistry, Faculty of Engineering, Kanagawa University 3-27-1 Rokkakubashi, Kanagawa-ku, Yokohama 221-8686, Japan
| | - Yosuke Chiba
- Department of Material and Life Chemistry, Faculty of Engineering, Kanagawa University 3-27-1 Rokkakubashi, Kanagawa-ku, Yokohama 221-8686, Japan
| | - Jun Nakazawa
- Department of Material and Life Chemistry, Faculty of Engineering, Kanagawa University 3-27-1 Rokkakubashi, Kanagawa-ku, Yokohama 221-8686, Japan
| | - Shiro Hikichi
- Department of Material and Life Chemistry, Faculty of Engineering, Kanagawa University 3-27-1 Rokkakubashi, Kanagawa-ku, Yokohama 221-8686, Japan
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21
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Cook BJ, Pink M, Pal K, Caulton KG. Electron and Oxygen Atom Transfer Chemistry of Co(II) in a Proton Responsive, Redox Active Ligand Environment. Inorg Chem 2018; 57:6176-6185. [DOI: 10.1021/acs.inorgchem.8b00816] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Brian J. Cook
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Maren Pink
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Kuntal Pal
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Kenneth G. Caulton
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
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22
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Zhang LL, Wang XY, Jiang KY, Zhao BY, Yan HM, Zhang XY, Zhang ZX, Guo Z, Che CM. A theoretical study on the oxidation of alkenes to aldehydes catalyzed by ruthenium porphyrins using O 2 as the sole oxidant. Dalton Trans 2018; 47:5286-5297. [PMID: 29569676 DOI: 10.1039/c8dt00614h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Density functional theory (DFT) calculations were used to study the ruthenium porphyrin-catalyzed oxidation of styrene to generate an aldehyde. The results indicate that two reactive oxidants, dioxoruthenium and monooxoruthenium-superoxo porphyrins, participate in the catalytic oxidation. In the mechanism, the resultant monooxoruthenium porphyrin acts in the tandem epoxide isomerization (E-I) to selectively yield an aldehyde and generate a dioxoruthenium porphyrin, thereby triggering new oxidation reaction cycles. In this calculation, several key elements responsible for the observed oxidative ability have been established by using Frontier molecular orbital (FMO) theory, natural bond orbital (NBO) analysis, etc., which include the reaction energy, the spin exchange effect, the spin-state conversion process, and the energy level of the lowest unoccupied molecular orbitals (LUMOs) of the reactive oxidants. The comparative oxidative abilities of the ruthenium-oxo/superoxo compounds with different axial ligands are also investigated. The results suggest that the ruthenium-oxo/superoxo species featuring a chlorine axial ligand is more reactive than that substituted with oxygen. This tuneable reactivity can be understood when considering the different electronic characters of the two ligands and the effective atomic number rule (EAN).
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Affiliation(s)
- Lin-Lin Zhang
- College of Material Science & Engineering, Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Shanxi, 030024, P. R. China.
| | - Xiang-Yun Wang
- College of Material Science & Engineering, Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Shanxi, 030024, P. R. China.
| | - Kun-Yao Jiang
- College of Material Science & Engineering, Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Shanxi, 030024, P. R. China.
| | - Bing-Yuan Zhao
- College of Material Science & Engineering, Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Shanxi, 030024, P. R. China.
| | - Hui-Min Yan
- College of Material Science & Engineering, Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Shanxi, 030024, P. R. China.
| | - Xiao-Yun Zhang
- College of Material Science & Engineering, Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Shanxi, 030024, P. R. China.
| | - Zhu-Xia Zhang
- College of Material Science & Engineering, Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Shanxi, 030024, P. R. China.
| | - Zhen Guo
- College of Material Science & Engineering, Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Shanxi, 030024, P. R. China.
| | - Chi-Ming Che
- Department of Chemistry, the University of Hong Kong, Hong Kong, P. R. China.
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23
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Cook BJ, Chen CH, Caulton KG. A Multifunctional Pincer Ligand for Cobalt-Promoted Oxidation by N 2 O. Chemistry 2018; 24:5962-5966. [PMID: 29437249 DOI: 10.1002/chem.201800086] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Indexed: 12/22/2022]
Abstract
The divalent cobalt complex of the diprotic pincer ligand bis-pyrazolylpyridine, (H2 L)CoCl2 , is dehydrohalogenated twice by LiN(SiMe3 )2 in the presence of PEt3 to give monomeric S=1/2 LCo(PEt3 )2 (1), fully characterized in the solid-state and solution as a square pyramidal monomer with a long axial Co-P bond. This 17-electron species reacts in time of mixing with N2 O to form L2 Co2 (μ-OPEt3 ) (2)+3 OPEt3 , the former the first example of phosphine oxide bridging two transition metals. The same products are formed from O2 , and divalent cobalt persists even in the presence of excess oxidant. Species (2) catalyzes oxygen atom transfer (OAT) for generation of O=PEt3 from PEt3 from either N2 O or O2 . Bridging and terminal cobalt oxo intermediates are suggested, and the electron donor power, and potential redox activity of the dianionic pincer ligand is emphasized.
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Affiliation(s)
- Brian J Cook
- Department of Chemistry, Indiana University, 800 E Kirkwood Ave, Bloomington, IN, 47405, USA
| | - Chun-Hsing Chen
- Department of Chemistry, Indiana University, 800 E Kirkwood Ave, Bloomington, IN, 47405, USA.,Molecular Structure Center, Indiana University, 800 E Kirkwood Ave, Bloomington, IN, 47405, USA
| | - Kenneth G Caulton
- Department of Chemistry, Indiana University, 800 E Kirkwood Ave, Bloomington, IN, 47405, USA
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24
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Saha S, Ghosh S, Gogoi K, Deka H, Mondal B, Mondal B. Reaction of a Co(III)-Peroxo Complex and NO: Formation of a Putative Peroxynitrite Intermediate. Inorg Chem 2017; 56:10932-10938. [DOI: 10.1021/acs.inorgchem.7b01110] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Soumen Saha
- Department of Chemistry, Indian Institute of Technology Guwahati, North Guwahati, Assam 781039, India
| | - Somnath Ghosh
- Department of Chemistry, Indian Institute of Technology Guwahati, North Guwahati, Assam 781039, India
| | - Kuldeep Gogoi
- Department of Chemistry, Indian Institute of Technology Guwahati, North Guwahati, Assam 781039, India
| | - Hemanta Deka
- Department of Chemistry, Indian Institute of Technology Guwahati, North Guwahati, Assam 781039, India
| | - Baishakhi Mondal
- Department of Chemistry, Indian Institute of Technology Guwahati, North Guwahati, Assam 781039, India
| | - Biplab Mondal
- Department of Chemistry, Indian Institute of Technology Guwahati, North Guwahati, Assam 781039, India
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25
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Kiernicki JJ, Staun SL, Zeller M, Bart SC. A Uranium(IV) Triamide Species with Brønsted Basic Ligand Character: Metal–Ligand Cooperativity in the f Block. Organometallics 2017. [DOI: 10.1021/acs.organomet.6b00861] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- John J. Kiernicki
- H.C. Brown Laboratory, Department
of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Selena L. Staun
- H.C. Brown Laboratory, Department
of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Matthias Zeller
- H.C. Brown Laboratory, Department
of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Suzanne C. Bart
- H.C. Brown Laboratory, Department
of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
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26
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Zhang Q, Bell-Taylor A, Bronston FM, Gorden JD, Goldsmith CR. Aldehyde Deformylation and Catalytic C–H Activation Resulting from a Shared Cobalt(II) Precursor. Inorg Chem 2016; 56:773-782. [DOI: 10.1021/acs.inorgchem.6b02127] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Qiao Zhang
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, United States
| | - Angela Bell-Taylor
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, United States
| | - Fraser M. Bronston
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, United States
| | - John D. Gorden
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, United States
| | - Christian R. Goldsmith
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, United States
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27
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Oxygen activation by mononuclear Mn, Co, and Ni centers in biology and synthetic complexes. J Biol Inorg Chem 2016; 22:407-424. [PMID: 27853875 DOI: 10.1007/s00775-016-1402-7] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 10/21/2016] [Indexed: 10/20/2022]
Abstract
The active sites of metalloenzymes that catalyze O2-dependent reactions generally contain iron or copper ions. However, several enzymes are capable of activating O2 at manganese or nickel centers instead, and a handful of dioxygenases exhibit activity when substituted with cobalt. This minireview summarizes the catalytic properties of oxygenases and oxidases with mononuclear Mn, Co, or Ni active sites, including oxalate-degrading oxidases, catechol dioxygenases, and quercetin dioxygenase. In addition, recent developments in the O2 reactivity of synthetic Mn, Co, or Ni complexes are described, with an emphasis on the nature of reactive intermediates featuring superoxo-, peroxo-, or oxo-ligands. Collectively, the biochemical and synthetic studies discussed herein reveal the possibilities and limitations of O2 activation at these three "overlooked" metals.
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28
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Shin B, Sutherlin KD, Ohta T, Ogura T, Solomon EI, Cho J. Reactivity of a Cobalt(III)-Hydroperoxo Complex in Electrophilic Reactions. Inorg Chem 2016; 55:12391-12399. [PMID: 27934432 DOI: 10.1021/acs.inorgchem.6b02288] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reactivity of mononuclear metal-hydroperoxo adducts has fascinated researchers in many areas due to their diverse biological and catalytic processes. In this study, a mononuclear cobalt(III)-peroxo complex bearing a tetradentate macrocyclic ligand, [CoIII(Me3-TPADP)(O2)]+ (Me3-TPADP = 3,6,9-trimethyl-3,6,9-triaza-1(2,6)-pyridinacyclodecaphane), was prepared by reacting [CoII(Me3-TPADP)(CH3CN)2]2+ with H2O2 in the presence of triethylamine. Upon protonation, the cobalt(III)-peroxo intermediate was converted into a cobalt(III)-hydroperoxo complex, [CoIII(Me3-TPADP)(O2H)(CH3CN)]2+. The mononuclear cobalt(III)-peroxo and -hydroperoxo intermediates were characterized by a variety of physicochemical methods. Results of electrospray ionization mass spectrometry clearly show the transformation of the intermediates: the peak at m/z 339.2 assignable to the cobalt(III)-peroxo species disappears with concomitant growth of the peak at m/z 190.7 corresponding to the cobalt(III)-hydroperoxo complex (with bound CH3CN). Isotope labeling experiments further support the existence of the cobalt(III)-peroxo and -hydroperoxo complexes. In particular, the O-O bond stretching frequency of the cobalt(III)-hydroperoxo complex was determined to be 851 cm-1 for 16O2H samples (803 cm-1 for 18O2H samples), and its Co-O vibrational energy was observed at 571 cm-1 for 16O2H samples (551 cm-1 for 18O2H samples; 568 cm-1 for 16O22H samples) by resonance Raman spectroscopy. Reactivity studies performed with the cobalt(III)-peroxo and -hydroperoxo complexes in organic functionalizations reveal that the latter is capable of conducting oxygen atom transfer with an electrophilic character, whereas the former exhibits no oxygen atom transfer reactivity under the same reaction conditions. Alternatively, the cobalt(III)-hydroperoxo complex does not perform hydrogen atom transfer reactions, while analogous low-spin Fe(III)-hydroperoxo complexes are capable of this reactivity. Density functional theory calculations indicate that this lack of reactivity is due to the high free energy cost of O-O bond homolysis that would be required to produce the hypothetical Co(IV)-oxo product.
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Affiliation(s)
- Bongki Shin
- Department of Emerging Materials Science, DGIST , Daegu 42988, Korea
| | - Kyle D Sutherlin
- Department of Chemistry, Stanford University , Stanford, California 94305, United States
| | - Takehiro Ohta
- Picobiology Institute, Graduate School of Life Science, University of Hyogo , RSC-UH LP Center, Hyogo 679-5148, Japan
| | - Takashi Ogura
- Picobiology Institute, Graduate School of Life Science, University of Hyogo , RSC-UH LP Center, Hyogo 679-5148, Japan
| | - Edward I Solomon
- Department of Chemistry, Stanford University , Stanford, California 94305, United States.,Stanford Synchrotron Radiation Laboratory, Stanford Linear Accelerator Center , Menlo Park, California 94025, United States
| | - Jaeheung Cho
- Department of Emerging Materials Science, DGIST , Daegu 42988, Korea
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29
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Wang CC, Chang HC, Lai YC, Fang H, Li CC, Hsu HK, Li ZY, Lin TS, Kuo TS, Neese F, Ye S, Chiang YW, Tsai ML, Liaw WF, Lee WZ. A Structurally Characterized Nonheme Cobalt–Hydroperoxo Complex Derived from Its Superoxo Intermediate via Hydrogen Atom Abstraction. J Am Chem Soc 2016; 138:14186-14189. [DOI: 10.1021/jacs.6b08642] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Chun-Chieh Wang
- Department
of Chemistry and Instrumentation Center, National Taiwan Normal University, Taipei 11677, Taiwan
- Department
of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Hao-Ching Chang
- Department
of Chemistry and Instrumentation Center, National Taiwan Normal University, Taipei 11677, Taiwan
| | - Yei-Chen Lai
- Department
of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Huayi Fang
- Max-Planck Institut für Chemische Energiekonversion, Mülheim an der Ruhr D-45470, Germany
| | - Chieh-Chin Li
- Department
of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Hung-Kai Hsu
- Department
of Chemistry and Instrumentation Center, National Taiwan Normal University, Taipei 11677, Taiwan
| | - Zong-Yan Li
- Department
of Chemistry and Instrumentation Center, National Taiwan Normal University, Taipei 11677, Taiwan
| | - Tien-Sung Lin
- Department
of Chemistry, Washington University, St. Louis, Missouri 63130, United States
| | - Ting-Shen Kuo
- Department
of Chemistry and Instrumentation Center, National Taiwan Normal University, Taipei 11677, Taiwan
| | - Frank Neese
- Max-Planck Institut für Chemische Energiekonversion, Mülheim an der Ruhr D-45470, Germany
| | - Shengfa Ye
- Max-Planck Institut für Chemische Energiekonversion, Mülheim an der Ruhr D-45470, Germany
| | - Yun-Wei Chiang
- Department
of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Ming-Li Tsai
- Department
of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan
| | - Wen-Feng Liaw
- Department
of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Way-Zen Lee
- Department
of Chemistry and Instrumentation Center, National Taiwan Normal University, Taipei 11677, Taiwan
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30
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Prakash J, Rohde GT, Meier KK, Münck E, Que L. Upside Down! Crystallographic and Spectroscopic Characterization of an [Fe IV(O syn)(TMC)]2+ Complex. Inorg Chem 2015; 54:11055-7. [PMID: 26615667 DOI: 10.1021/acs.inorgchem.5b02011] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Fe(II)(TMC)(OTf)2 reacts with 2-(t)BuSO2-C6H4IO to afford an oxoiron(IV) product, 2, distinct from the previously reported [Fe(IV)(Oanti)(TMC)(NCMe)](2+). In MeCN, 2 has a blue-shifted near-IR band, a higher ν(Fe═O), a larger Mössbauer quadrupole splitting, and quite a distinct (1)H NMR spectrum. Structural analysis of crystals grown from CH2Cl2 reveals a complex with the formulation of [Fe(IV)(Osyn)(TMC)(OTf)](OTf) and the shortest Fe(IV)═O bond [1.625(4) Å] found to date.
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Affiliation(s)
- Jai Prakash
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Gregory T Rohde
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Katlyn K Meier
- Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Eckard Münck
- Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Lawrence Que
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota , Minneapolis, Minnesota 55455, United States
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31
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Kim J, Shin B, Kim H, Lee J, Kang J, Yanagisawa S, Ogura T, Masuda H, Ozawa T, Cho J. Steric Effect on the Nucleophilic Reactivity of Nickel(III) Peroxo Complexes. Inorg Chem 2015; 54:6176-83. [DOI: 10.1021/acs.inorgchem.5b00294] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jalee Kim
- Department of Emerging
Materials Science, DGIST, Daegu 711-873, Korea
| | - Bongki Shin
- Department of Emerging
Materials Science, DGIST, Daegu 711-873, Korea
| | - Hyunjeong Kim
- Department of Emerging
Materials Science, DGIST, Daegu 711-873, Korea
| | - Junhyung Lee
- Department of Emerging
Materials Science, DGIST, Daegu 711-873, Korea
| | - Joongoo Kang
- Department of Emerging
Materials Science, DGIST, Daegu 711-873, Korea
| | - Sachiko Yanagisawa
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, Hyogo 678-1297, Japan
| | - Takashi Ogura
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, Hyogo 678-1297, Japan
| | - Hideki Masuda
- Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
| | - Tomohiro Ozawa
- Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
| | - Jaeheung Cho
- Department of Emerging
Materials Science, DGIST, Daegu 711-873, Korea
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32
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Kim S, Ginsbach JW, Lee JY, Peterson RL, Liu JJ, Siegler MA, Sarjeant AA, Solomon EI, Karlin KD. Amine oxidative N-dealkylation via cupric hydroperoxide Cu-OOH homolytic cleavage followed by site-specific fenton chemistry. J Am Chem Soc 2015; 137:2867-74. [PMID: 25706825 PMCID: PMC4482616 DOI: 10.1021/ja508371q] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Copper(II) hydroperoxide species are significant intermediates in processes such as fuel cells and (bio)chemical oxidations, all involving stepwise reduction of molecular oxygen. We previously reported a Cu(II)-OOH species that performs oxidative N-dealkylation on a dibenzylamino group that is appended to the 6-position of a pyridyl donor of a tripodal tetradentate ligand. To obtain insights into the mechanism of this process, reaction kinetics and products were determined employing ligand substrates with various para-substituent dibenzyl pairs (-H,-H; -H,-Cl; -H,-OMe, and -Cl,-OMe), or with partially or fully deuterated dibenzyl N-(CH2Ph)2 moieties. A series of ligand-copper(II) bis-perchlorate complexes were synthesized, characterized, and the X-ray structures of the -H,-OMe analogue were determined. The corresponding metastable Cu(II)-OOH species were generated by addition of H2O2/base in acetone at -90 °C. These convert (t1/2 ≈ 53 s) to oxidatively N-dealkylated products, producing para-substituted benzaldehydes. Based on the experimental observations and supporting DFT calculations, a reaction mechanism involving dibenzylamine H-atom abstraction or electron-transfer oxidation by the Cu(II)-OOH entity could be ruled out. It is concluded that the chemistry proceeds by rate limiting Cu-O homolytic cleavage of the Cu(II)-(OOH) species, followed by site-specific copper Fenton chemistry. As a process of broad interest in copper as well as iron oxidative (bio)chemistries, a detailed computational analysis was performed, indicating that a Cu(I)OOH species undergoes O-O homolytic cleavage to yield a hydroxyl radical and Cu(II)OH rather than heterolytic cleavage to yield water and a Cu(II)-O(•-) species.
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Affiliation(s)
- Sunghee Kim
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218
| | - Jake W. Ginsbach
- Department of Chemistry, Stanford University, Stanford, California 94305
| | - Jung Yoon Lee
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218
| | - Ryan L. Peterson
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218
| | - Jeffrey J. Liu
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218
| | - Maxime A. Siegler
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218
| | - Amy A. Sarjeant
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218
| | - Edward I. Solomon
- Department of Chemistry, Stanford University, Stanford, California 94305
| | - Kenneth D. Karlin
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218
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33
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Ray K, Pfaff FF, Wang B, Nam W. Status of Reactive Non-Heme Metal–Oxygen Intermediates in Chemical and Enzymatic Reactions. J Am Chem Soc 2014; 136:13942-58. [DOI: 10.1021/ja507807v] [Citation(s) in RCA: 351] [Impact Index Per Article: 35.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Kallol Ray
- Department
of Chemistry, Humboldt-Universität zu Berlin, 12489 Berlin, Germany
| | - Florian Felix Pfaff
- Department
of Chemistry, Humboldt-Universität zu Berlin, 12489 Berlin, Germany
| | - Bin Wang
- Department
of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750, Korea
| | - Wonwoo Nam
- Department
of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750, Korea
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