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Yao X, Ji Y, Huang ZQ, Zhao Z, Gao P, Guo M, Liu X, Meng C, Fu Q, Chang CR, Bao X, Hou G. Nondissociative Activated Dihydrogen Binding on CeO 2 Revealed by High-Pressure Operando Solid-State NMR Spectroscopy. J Am Chem Soc 2024; 146:24609-24618. [PMID: 39178352 DOI: 10.1021/jacs.4c08258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/25/2024]
Abstract
Dihydrogen complexes, which retain the H-H bond, have been extensively studied in molecular science and found to be prevalent in homogeneous and enzymatic catalysis. However, their counterparts in heterogeneous catalysis, specifically nondissociative chemisorbed dihydrogen binding on the catalyst surface, are rarely reported experimentally. This scarcity is due to the complexity of typical material surfaces and the lack of effective characterization techniques to prove and distinguish various dihydrogen binding modes. Herein, using high-pressure operando solid-state NMR technology, we report the first unambiguous experimental observation of activated dihydrogen binding on a reduced ceria catalyst through interactions with surface oxygen vacancies. By employing versatile NMR structural and dynamical analysis methods, we establish a proportional relationship between the degree of ceria surface reduction and dihydrogen binding, as evidenced by NMR observations of H-D through-bond coupling (JHD), T1 relaxation, and proton isotropic chemical shifts. In situ NMR analysis further reveals the participation of bound dihydrogen species in a room-temperature ethylene hydrogenation reaction. The remarkable similarities between surface-activated dihydrogen in heterogeneous catalysis and dihydrogen model molecular complexes can provide valuable insights into the hydrogenation mechanism for many other solid catalysts, potentially enhancing hydrogen utilization.
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Affiliation(s)
- Xinlong Yao
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yi Ji
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
| | - Zheng-Qing Huang
- Shaanxi Key Laboratory of Energy Chemical Process Intensification, School of Chemical Engineering and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Zhenchao Zhao
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
| | - Pan Gao
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
| | - Meiling Guo
- Energy Innovation Laboratory, BP (China) Dalian Office, Dalian 116023, China
| | - Xuebin Liu
- Energy Innovation Laboratory, BP (China) Dalian Office, Dalian 116023, China
| | - Caixia Meng
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
| | - Qiang Fu
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
| | - Chun-Ran Chang
- Shaanxi Key Laboratory of Energy Chemical Process Intensification, School of Chemical Engineering and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Xinhe Bao
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
| | - Guangjin Hou
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
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2
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Huang TH, Luo C, Zhao FZ, Zheng D, Hu QL, Jia L. Influence of different solvents on structures and electronic properties of new Fe2S2 complexes containing bis(2-diphenylphosphinophenyl)ether. J Mol Struct 2021. [DOI: 10.1016/j.molstruc.2021.130848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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4
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Spectroscopic and electrochemical comparison of [FeFe]-hydrogenase active-site inspired compounds: Diiron monobenzenethiolate compounds containing electron-donating and withdrawing groups. Polyhedron 2021. [DOI: 10.1016/j.poly.2021.115043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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5
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Arrigoni F, Bertini L, De Gioia L, Zampella G, Mazzoni R, Cingolani A, Gualandi I, Tonelli D, Zanotti V. On the importance of cyanide in diiron bridging carbyne complexes, unconventional [FeFe]-hydrogenase mimics without dithiolate: An electrochemical and DFT investigation. Inorganica Chim Acta 2020. [DOI: 10.1016/j.ica.2020.119745] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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6
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Kerns SA, Rose MJ. Scaffold-Based Functional Models of [Fe]-Hydrogenase (Hmd): Building the Bridge between Biological Structure and Molecular Function. Acc Chem Res 2020; 53:1637-1647. [PMID: 32786339 DOI: 10.1021/acs.accounts.0c00315] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The well-known dinuclear [FeFe] and [NiFe] hydrogenase enzymes are redox-based proton reduction and H2 oxidation catalysts. In comparison, the structural and functional aspects of the mononuclear nonredox hydrogenase, known as [Fe]-hydrogenase or Hmd, have been less explored because of the relatively recent crystallographic elucidation of the enzyme active site. Additionally, the synthetic challenges posed by the highly substituted and asymmetric coordination environment of the iron guanylylpyridinol (FeGP) cofactor have hampered functional biomimetic modeling studies to a large extent. The active site contains an octahedral low-spin Fe(II) center with the following coordination motifs: a bidentate acyl-pyridone moiety (C,N) and cysteinyl-S in a facial arrangement; two cis carbonyl ligands; and a H2O/H2 binding site. In [Fe]-hydrogenase, heterolytic H2 activation putatively by the pendant pyridone/pyridonate-O base serving as a proton acceptor. Following H2 cleavage, an intermediate Fe-H species is thought to stereoselectively transfer a hydride to the substrate methenyl-H4MPT+, thus forming methylene-H4MPT. In the past decade, chemists, inspired by the elegant organometallic chemistry inherent to the FeGP cofactor, have synthesized a number of faithful structural models. However, functional systems are still relatively limited and often rely on abiological ligands or metal centers that obfuscate a direct correlation to nature's design.Our group has developed a bioinspired suite of synthetic analogues of Hmd to better understand the effects of structure on the stability and functionality of the Hmd active site, with a special emphasis on using a scaffold-based ligand design. This systematic approach has contributed to a deeper understanding of the unique ligand array of [Fe]-hydrogenase in nature and has ultimately resulted in the first functional synthetic models without the aid of abiological ligands. This Account reviews the reactivity of the functional anthracene-scaffolded synthetic models developed by our group in the context of current mechanistic understanding drawn from both protein crystallography and computational studies. Furthermore, we introduce a novel thermodynamic framework to place the reactivity of our model systems in context and provide an outlook on the future study of [Fe]-hydrogenase synthetic models through both a structural and functional lens.
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Affiliation(s)
- Spencer A. Kerns
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Michael J. Rose
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
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7
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Demianets I, Cherepakhin V, Maertens A, Lauridsen PJ, Sharada SM, Williams TJ. A New Mechanism of Metal-Ligand Cooperative Catalysis in Transfer Hydrogenation of Ketones. Polyhedron 2020; 182. [PMID: 32410767 DOI: 10.1016/j.poly.2020.114508] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
We report iridium catalysts IrCl(η5-Cp*)(κ2-(2-pyridyl)CH2NSO2C6H4X) (1-Me, X = CH3 and 1-F, X = F) for transfer hydrogenation of ketones with 2-propanol that operate by a previously unseen metal-ligand cooperative mechanism. Under the reaction conditions, complexes 1 (1-Me and 1-F) derivatize to a series of catalytic intermediates: Ir(η5-Cp*)(κ2-(C5H4N)CHNSO2Ar) (2), IrH(η5Cp*)(κ2-(2-pyridyl)CH2NSO2Ar) (3), and Ir(η5-Cp*)(κ3-(2-pyridyl)CH2NSO2Ar) (4). The structures of 1-Me and 4-Me were established by single-crystal X-ray diffraction. A rate-determining, concerted hydrogen transfer step (2 + R2CHOH ⇄ 3 + R2CO) is suggested by kinetic isotope effects, Eyring parameters (ΔH ≠ = 29.1(8) kcal mol-1 and ΔS ≠ = -17(19) eu), proton-hydride fidelity, and DFT calculations. According to DFT, a nine-membered cyclic transition state is stabilized by an alcohol molecule that serves as a proton shuttle.
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Affiliation(s)
- Ivan Demianets
- Donald P. and Katherine B. Loker Hydrocarbon Institute and Department of Chemistry, University of Southern California, Los Angeles, California, 90089-1661, United States
| | - Valeriy Cherepakhin
- Donald P. and Katherine B. Loker Hydrocarbon Institute and Department of Chemistry, University of Southern California, Los Angeles, California, 90089-1661, United States
| | - Alexander Maertens
- Donald P. and Katherine B. Loker Hydrocarbon Institute and Department of Chemistry, University of Southern California, Los Angeles, California, 90089-1661, United States
| | - Paul J Lauridsen
- Donald P. and Katherine B. Loker Hydrocarbon Institute and Department of Chemistry, University of Southern California, Los Angeles, California, 90089-1661, United States
| | - Shaama Mallikarjun Sharada
- Department of Chemistry, University of Southern California, Los Angeles, California, 90089, United States
| | - Travis J Williams
- Donald P. and Katherine B. Loker Hydrocarbon Institute and Department of Chemistry, University of Southern California, Los Angeles, California, 90089-1661, United States
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8
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Arnett CH, Agapie T. Activation of an Open Shell, Carbyne-Bridged Diiron Complex Toward Binding of Dinitrogen. J Am Chem Soc 2020; 142:10059-10068. [DOI: 10.1021/jacs.0c01896] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Charles H. Arnett
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Theodor Agapie
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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9
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Isegawa M, Matsumoto T, Ogo S. Selective Oxidation of H 2 and CO by NiIr Catalyst in Aqueous Solution: A DFT Mechanistic Study. Inorg Chem 2020; 59:1014-1028. [PMID: 31898897 DOI: 10.1021/acs.inorgchem.9b02400] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
One of the challenges in utilizing hydrogen gas (H2) as a sustainable fossil fuel alternative is the inhibition of H2 oxidation by carbon monoxide (CO), which is involved in the industrial production of H2 sources. To solve this problem, a catalyst that selectively oxidizes either CO or H2 or one that co-oxidizes H2 and CO is needed. Recently, a NiIr catalyst [NiIICl(X)IrIIICl(η5-C5Me5)], (X = N,N'-dimethyl-3,7-diazanonane-1,9-dithiolate), which efficiently and selectively oxidizes either H2 or CO depending on the pH, has been developed (Angew. Chem. Int. Ed. 2017, 56, 9723-9726). In the present work, density functional theory (DFT) calculations are employed to elucidate the pH-dependent reaction mechanisms of H2 and CO oxidation catalyzed by this NiIr catalyst. During H2 oxidation, our calculations suggest that dihydrogen binds to the Ir center and generates an Ir(III)-dihydrogen complex, followed by subsequent isomerization to an Ir(V)-dihydride species. Then, a proton is abstracted by a buffer base, CH3COO-, resulting in the formation of a hydride complex. The catalytic cycle completes with electron transfer from the hydride complex to a protonated 2,6-dichlorobenzeneindophenol (DCIP) and a proton transfer from the oxidized hydride complex to a buffer base. The CO oxidation mechanism involves three distinct steps, i.e., (1) formation of a metal carbonyl complex, (2) formation of a metallocarboxylic acid, and (3) conversion of the metallocarboxylic acid to a hydride complex. The formation of the metallocarboxylic acid involves nucleophilic attack of OH- to the carbonyl-C followed by a large structural change with concomitant cleavage of the Ir-S bond and rotation of the COOH group along the NiIr axis. During the conversion of the metallocarboxylic acid to the hydride complex, intramolecular proton transfer followed by removal of CO2 leads to the formation of the hydride complexes. In addition, the barrier heights for the binding of small molecules (H2, OH-, H2O, and CO) to Ir were calculated, and the results indicated that dissociation from Ir is a faster process than the binding of H2O and H2. These calculations indicate that H2 oxidation is inhibited by CO and OH- and thus prefers acidic conditions. In contrast, the CO oxidation reactions occur more favorably under basic conditions, as the formation of the metallocarboxylic acid involves OH- attack to a carbonyl-C and the binding of OH- to Ni largely stabilizes the triplet spin state of the complex. Taken together, these calculations provide a rationale for the experimentally observed pH-dependent, selective oxidations of H2 and CO.
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Affiliation(s)
- Miho Isegawa
- International Institute for Carbon-Neutral Energy Research (WPI-I2CNER) , Kyushu University , 744 Moto-oka , Nishi-ku, Fukuoka 819-0395 , Japan
| | - Takahiro Matsumoto
- International Institute for Carbon-Neutral Energy Research (WPI-I2CNER) , Kyushu University , 744 Moto-oka , Nishi-ku, Fukuoka 819-0395 , Japan
| | - Seiji Ogo
- International Institute for Carbon-Neutral Energy Research (WPI-I2CNER) , Kyushu University , 744 Moto-oka , Nishi-ku, Fukuoka 819-0395 , Japan
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10
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Arrigoni F, Bertini L, Breglia R, Greco C, De Gioia L, Zampella G. Catalytic H 2 evolution/oxidation in [FeFe]-hydrogenase biomimetics: account from DFT on the interplay of related issues and proposed solutions. NEW J CHEM 2020. [DOI: 10.1039/d0nj03393f] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A DFT overview on selected issues regarding diiron catalysts related to [FeFe]-hydrogenase biomimetic research, with implications for both energy conversion and storage strategies.
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Affiliation(s)
- Federica Arrigoni
- Department of Biotechnology and Biosciences
- University of Milano – Bicocca
- 20126 Milan
- Italy
| | - Luca Bertini
- Department of Biotechnology and Biosciences
- University of Milano – Bicocca
- 20126 Milan
- Italy
| | - Raffaella Breglia
- Department of Biotechnology and Biosciences
- University of Milano – Bicocca
- 20126 Milan
- Italy
- Department of Earth and Environmental Sciences
| | - Claudio Greco
- Department of Biotechnology and Biosciences
- University of Milano – Bicocca
- 20126 Milan
- Italy
- Department of Earth and Environmental Sciences
| | - Luca De Gioia
- Department of Biotechnology and Biosciences
- University of Milano – Bicocca
- 20126 Milan
- Italy
| | - Giuseppe Zampella
- Department of Biotechnology and Biosciences
- University of Milano – Bicocca
- 20126 Milan
- Italy
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11
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Ghosh S, Rahaman A, Orton G, Gregori G, Bernat M, Kulsume U, Hollingsworth N, Holt KB, Kabir SE, Hogarth G. Synthesis, Molecular Structures and Electrochemical Investigations of [FeFe]‐Hydrogenase Biomimics [Fe
2
(CO)
6‐
n
(EPh
3
)
n
(µ‐edt)] (E = P, As, Sb;
n
= 1, 2). Eur J Inorg Chem 2019. [DOI: 10.1002/ejic.201900891] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Shishir Ghosh
- Department of Chemistry University College London 20 Gordon Street WC1H 0AJ London UK
- Department of Chemistry Jahangirnagar University Dhaka 1342 Savar Bangladesh
- Department of Chemistry King's College London Britannia House 7 Trinity Street SE1 1DB London UK
| | - Ahibur Rahaman
- Department of Chemistry Jahangirnagar University Dhaka 1342 Savar Bangladesh
| | - Georgia Orton
- Department of Chemistry King's College London Britannia House 7 Trinity Street SE1 1DB London UK
| | - Gregory Gregori
- Department of Chemistry University College London 20 Gordon Street WC1H 0AJ London UK
| | - Martin Bernat
- Department of Chemistry University College London 20 Gordon Street WC1H 0AJ London UK
| | - Ummey Kulsume
- Department of Chemistry Jahangirnagar University Dhaka 1342 Savar Bangladesh
| | - Nathan Hollingsworth
- Department of Chemistry University College London 20 Gordon Street WC1H 0AJ London UK
| | - Katherine B. Holt
- Department of Chemistry University College London 20 Gordon Street WC1H 0AJ London UK
| | - Shariff E. Kabir
- Department of Chemistry Jahangirnagar University Dhaka 1342 Savar Bangladesh
| | - Graeme Hogarth
- Department of Chemistry King's College London Britannia House 7 Trinity Street SE1 1DB London UK
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12
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Donovan ES, Plummer HM, Parada AS, Nichol GS, Felton GA. Pnictogen ligand coordination to an iron-sulfur compound. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2018.12.035] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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13
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Förster A, Gemming S, Seifert G, Tománek D. Chemical and Electronic Repair Mechanism of Defects in MoS 2 Monolayers. ACS NANO 2017; 11:9989-9996. [PMID: 28915006 DOI: 10.1021/acsnano.7b04162] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Using ab initio density functional theory calculations, we characterize changes in the electronic structure of MoS2 monolayers introduced by missing or additional adsorbed sulfur atoms. We furthermore identify the chemical and electronic function of substances that have been reported to reduce the adverse effect of sulfur vacancies in quenching photoluminescence and reducing electronic conductance. We find that thiol-group-containing molecules adsorbed at vacancy sites may reinsert missing sulfur atoms. In the presence of additional adsorbed sulfur atoms, thiols may form disulfides on the MoS2 surface to mitigate the adverse effect of defects.
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Affiliation(s)
- Anja Förster
- Physics and Astronomy Department, Michigan State University , East Lansing, Michigan 48824, United States
- Center for Advancing Electronics Dresden (cfaed) , 01062 Dresden, Germany
- Theoretical Chemistry, Technische Universität Dresden , 01062 Dresden, Germany
| | - Sibylle Gemming
- Center for Advancing Electronics Dresden (cfaed) , 01062 Dresden, Germany
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research , Bautzner Landstrasse 400, 01328 Dresden, Germany
- Institute of Physics, Technische Universität Chemnitz , 09107 Chemnitz, Germany
| | - Gotthard Seifert
- Center for Advancing Electronics Dresden (cfaed) , 01062 Dresden, Germany
- Theoretical Chemistry, Technische Universität Dresden , 01062 Dresden, Germany
- National University of Science and Technology, MISIS , 119049 Moscow, Russia
| | - David Tománek
- Physics and Astronomy Department, Michigan State University , East Lansing, Michigan 48824, United States
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14
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Omann L, Königs CDF, Klare HFT, Oestreich M. Cooperative Catalysis at Metal-Sulfur Bonds. Acc Chem Res 2017; 50:1258-1269. [PMID: 28406290 DOI: 10.1021/acs.accounts.7b00089] [Citation(s) in RCA: 99] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Cooperative catalysis has attracted tremendous attention in recent years, emerging as a key strategy for the development of novel atom-economic and environmentally more benign catalytic processes. In particular, Noyori-type complexes with metal-nitrogen bonds have been extensively studied and evolved as privileged catalysts in hydrogenation chemistry. In contrast, catalysts containing metal-sulfur bonds as the reactive site are out of the ordinary, despite their abundance in living systems, where they are assumed to play a key role in biologically relevant processes. For instance, the heterolysis of dihydrogen catalyzed by [NiFe] hydrogenase is likely to proceed through cooperative H-H bond splitting at a polar nickel-sulfur bond. This Account provides an overview of reported metal-sulfur complexes that allow for cooperative E-H bond (E = H, Si, and B) activation and highlights the potential of this motif in catalytic applications. In recent years, our contributions to this research field have led to the development of a broad spectrum of synthetically useful transformations catalyzed by cationic ruthenium(II) thiolate complexes of type [(DmpS)Ru(PR3)]+BArF4- (DmpS = 2,6-dimesitylphenyl thiolate, ArF = 3,5-bis(trifluoromethyl)phenyl). The tethered coordination mode of the bulky 2,6-dimesitylphenyl thiolate ligand is crucial, stabilizing the coordinatively unsaturated ruthenium atom and also preventing formation of binuclear sulfur-bridged complexes. The ruthenium-sulfur bond of these complexes combines Lewis acidity at the metal center and Lewis basicity at the adjacent sulfur atom. This structural motif allows for reversible heterolytic splitting of E-H bonds (E = H, Si, and B) across the polar ruthenium-sulfur bond, generating a metal hydride and a sulfur-stabilized E+ cation. Hence, this activation mode provides a new strategy to catalytically generate silicon and boron electrophiles. After transfer of the electrophile to a Lewis-basic substrate, the resulting neutral ruthenium(II) hydride can either act as a hydride donor (reductant) or as a proton acceptor (Brønsted base); the latter scenario is followed by dihydrogen release. On the basis of this concept, the tethered ruthenium(II) thiolate complexes emerged as widely applicable catalysts for various transformations, which can be categorized into (i) dehydrogenative couplings [Si-C(sp2), Si-O, Si-N, and B-C(sp2)], (ii) chemoselective reductions (hydrogenation and hydrosilylation), and (iii) hydrodefluorination reactions. All reactions are promoted by a single catalyst motif through synergistic metal-sulfur interplay. The most prominent examples of these transformations are the first catalytic protocols for the regioselective C-H silylation and borylation of electron-rich heterocycles following a Friedel-Crafts mechanism.
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Affiliation(s)
- Lukas Omann
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany
| | - C. David F. Königs
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany
| | - Hendrik F. T. Klare
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany
| | - Martin Oestreich
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany
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15
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Schilter D, Camara JM, Huynh MT, Hammes-Schiffer S, Rauchfuss TB. Hydrogenase Enzymes and Their Synthetic Models: The Role of Metal Hydrides. Chem Rev 2016; 116:8693-749. [PMID: 27353631 PMCID: PMC5026416 DOI: 10.1021/acs.chemrev.6b00180] [Citation(s) in RCA: 397] [Impact Index Per Article: 49.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hydrogenase enzymes efficiently process H2 and protons at organometallic FeFe, NiFe, or Fe active sites. Synthetic modeling of the many H2ase states has provided insight into H2ase structure and mechanism, as well as afforded catalysts for the H2 energy vector. Particularly important are hydride-bearing states, with synthetic hydride analogues now known for each hydrogenase class. These hydrides are typically prepared by protonation of low-valent cores. Examples of FeFe and NiFe hydrides derived from H2 have also been prepared. Such chemistry is more developed than mimicry of the redox-inactive monoFe enzyme, although functional models of the latter are now emerging. Advances in physical and theoretical characterization of H2ase enzymes and synthetic models have proven key to the study of hydrides in particular, and will guide modeling efforts toward more robust and active species optimized for practical applications.
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Affiliation(s)
- David Schilter
- Center for Multidimensional Carbon Materials, Institute for Basic Science (IBS), Ulsan 44919, Republic of Korea
- Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
| | - James M. Camara
- Department of Chemistry, Yeshiva University, 500 West 185th Street, New York, New York 10033, United States
| | - Mioy T. Huynh
- Department of Chemistry, University of Illinois at Urbana–Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States
| | - Sharon Hammes-Schiffer
- Department of Chemistry, University of Illinois at Urbana–Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States
| | - Thomas B. Rauchfuss
- Department of Chemistry, University of Illinois at Urbana–Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States
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16
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Hunt A, Barrett J, McCurry M, Works C. Photochemical reactivity of a binuclear Fe(I)–Fe(I) hydrogenase model compound with cyano ligands. Polyhedron 2016. [DOI: 10.1016/j.poly.2016.01.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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17
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18
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Affiliation(s)
- Robert H. Crabtree
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520-8107, United States
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19
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Abstract
Transition metal hydride complexes are usually amphoteric, not only acting as hydride donors, but also as Brønsted-Lowry acids. A simple additive ligand acidity constant equation (LAC for short) allows the estimation of the acid dissociation constant Ka(LAC) of diamagnetic transition metal hydride and dihydrogen complexes. It is remarkably successful in systematizing diverse reports of over 450 reactions of acids with metal complexes and bases with metal hydrides and dihydrogen complexes, including catalytic cycles where these reactions are proposed or observed. There are links between pKa(LAC) and pKa(THF), pKa(DCM), pKa(MeCN) for neutral and cationic acids. For the groups from chromium to nickel, tables are provided that order the acidity of metal hydride and dihydrogen complexes from most acidic (pKa(LAC) -18) to least acidic (pKa(LAC) 50). Figures are constructed showing metal acids above the solvent pKa scales and organic acids below to summarize a large amount of information. Acid-base features are analyzed for catalysts from chromium to gold for ionic hydrogenations, bifunctional catalysts for hydrogen oxidation and evolution electrocatalysis, H/D exchange, olefin hydrogenation and isomerization, hydrogenation of ketones, aldehydes, imines, and carbon dioxide, hydrogenases and their model complexes, and palladium catalysts with hydride intermediates.
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Affiliation(s)
- Robert H Morris
- Department of Chemistry, University of Toronto , 80 Saint George Street, Toronto, Ontario M5S 3H6, Canada
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20
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Das UK, Daifuku SL, Gorelsky SI, Korobkov I, Neidig ML, Le Roy JJ, Murugesu M, Baker RT. Mononuclear, Dinuclear, and Trinuclear Iron Complexes Featuring a New Monoanionic SNS Thiolate Ligand. Inorg Chem 2016; 55:987-97. [PMID: 26741465 DOI: 10.1021/acs.inorgchem.5b02833] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The new tridentate ligand, S(Me)N(H)S = 2-(2-methylthiophenyl)benzothiazolidine, prepared in a single step from commercial precursors in excellent yield, undergoes ring-opening on treatment with Fe(OTf)2 in the presence of base affording a trinuclear iron complex, [Fe3(μ2-S(Me)NS(-))4](OTf)2 (1) which is fully characterized by structural and spectroscopic methods. X-ray structural data reveal that 1 contains four S(Me)NS(-) ligands meridionally bound to two pseudooctahedral iron centers each bridged by two thiolates to a distorted tetrahedral central iron. The combined spectroscopic (UV-vis, Mössbauer, NMR), magnetic (solution and solid state), and computational (DFT) studies indicate that 1 includes a central, high-spin Fe(II) (S = 2) with two low-spin (S = 0) peripheral Fe(II) centers. Complex 1 reacts with excess PMePh2, CNxylyl (2,6-dimethylphenyl isocyanide), and P(OMe)3 in CH3CN to form diamagnetic, thiolate-bridged, dinuclear Fe(II) complexes {[Fe(μ-S(Me)NS(-))L2]2}(OTf)2 (2-4). These complexes are characterized by elemental analysis; (1)H NMR, IR, UV-vis, and Mössbauer spectroscopy; and single crystal X-ray diffraction. Interestingly, addition of excess P(OMe)3 to complex 1 in CH2Cl2 produces primarily the diamagnetic, mononuclear Fe(II) complex, {Fe(S(Me)NS(-))[P(OMe)3]3}(OTf) (5).
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Affiliation(s)
- Uttam K Das
- Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, University of Ottawa , Ottawa, Ontario K1N 6N5, Canada
| | - Stephanie L Daifuku
- Department of Chemistry, University of Rochester , Rochester, New York 14627, United States
| | - Serge I Gorelsky
- Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, University of Ottawa , Ottawa, Ontario K1N 6N5, Canada
| | - Ilia Korobkov
- Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, University of Ottawa , Ottawa, Ontario K1N 6N5, Canada
| | - Michael L Neidig
- Department of Chemistry, University of Rochester , Rochester, New York 14627, United States
| | - Jennifer J Le Roy
- Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, University of Ottawa , Ottawa, Ontario K1N 6N5, Canada
| | - Muralee Murugesu
- Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, University of Ottawa , Ottawa, Ontario K1N 6N5, Canada
| | - R Tom Baker
- Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, University of Ottawa , Ottawa, Ontario K1N 6N5, Canada
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21
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Vedha SA, Velmurugan G, Venuvanalingam P. Noncovalent interactions between the second coordination sphere and the active site of [NiFeSe] hydrogenase. RSC Adv 2016. [DOI: 10.1039/c6ra11295a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
QM/MM studies on seven truncated models of the oxidized as-isolated state of the [NiFeSe] Hases reveal the influence of the residues in the second coordination sphere on the active site.
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Affiliation(s)
- Swaminathan Angeline Vedha
- Theoretical and Computational Chemistry Laboratory
- School of Chemistry
- Bharathidasan University
- Tiruchirappalli-620 024
- India
| | - Gunasekaran Velmurugan
- Theoretical and Computational Chemistry Laboratory
- School of Chemistry
- Bharathidasan University
- Tiruchirappalli-620 024
- India
| | - Ponnambalam Venuvanalingam
- Theoretical and Computational Chemistry Laboratory
- School of Chemistry
- Bharathidasan University
- Tiruchirappalli-620 024
- India
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22
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The Covalent Bond Classification Method and Its Application to Compounds That Feature 3-Center 2-Electron Bonds. THE CHEMICAL BOND III 2016. [DOI: 10.1007/430_2015_206] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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23
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Dub PA, Gordon JC. The mechanism of enantioselective ketone reduction with Noyori and Noyori–Ikariya bifunctional catalysts. Dalton Trans 2016; 45:6756-81. [DOI: 10.1039/c6dt00476h] [Citation(s) in RCA: 164] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The present article describes the current level of understanding of the mechanism of enantioselective hydrogenation and transfer hydrogenation of aromatic ketones with pioneering prototypes of bifunctional catalysts, the Noyori and Noyori–Ikariya complexes.
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Affiliation(s)
- Pavel A. Dub
- Chemistry Division
- Los Alamos National Laboratory
- Los Alamos
- USA
| | - John C. Gordon
- Chemistry Division
- Los Alamos National Laboratory
- Los Alamos
- USA
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24
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Gloaguen F. Electrochemistry of Simple Organometallic Models of Iron-Iron Hydrogenases in Organic Solvent and Water. Inorg Chem 2015; 55:390-8. [PMID: 26641526 DOI: 10.1021/acs.inorgchem.5b02245] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Synthetic models of the active site of iron-iron hydrogenases are currently the subjects of numerous studies aimed at developing H2-production catalysts based on cheap and abundant materials. In this context, the present report offers an electrochemist's view of the catalysis of proton reduction by simple binuclear iron(I) thiolate complexes. Although these complexes probably do not follow a biocatalytic pathway, we analyze and discuss the interplay between the reduction potential and basicity and how these antagonist properties impact the mechanisms of proton-coupled electron transfer to the metal centers. This question is central to any consideration of the activity at the molecular level of hydrogenases and related enzymes. In a second part, special attention is paid to iron thiolate complexes holding rigid and unsaturated bridging ligands. The complexes that enjoy mild reduction potentials and stabilized reduced forms are promising iron-based catalysts for the photodriven evolution of H2 in organic solvents and, more importantly, in water.
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Affiliation(s)
- Frederic Gloaguen
- UMR 6521, CNRS, Université de Bretagne Occidentale, CS 93837 , 29238 Brest, France
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25
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Kwan P, McIntosh CL, Jennings DP, Hopkins RC, Chandrayan SK, Wu CH, Adams MWW, Jones AK. The [NiFe]-Hydrogenase of Pyrococcus furiosus Exhibits a New Type of Oxygen Tolerance. J Am Chem Soc 2015; 137:13556-65. [PMID: 26436715 DOI: 10.1021/jacs.5b07680] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We report the first direct electrochemical characterization of the impact of oxygen on the hydrogen oxidation activity of an oxygen-tolerant, group 3, soluble [NiFe]-hydrogenase: hydrogenase I from Pyrococcus furiosus (PfSHI), which grows optimally near 100 °C. Chronoamperometric experiments were used to probe the sensitivity of PfSHI hydrogen oxidation activity to both brief and prolonged exposure to oxygen. For experiments between 15 and 80 °C, following short (<200 s) exposure to 14 μM O2 under oxidizing conditions, PfSHI always maintains some fraction of its initial hydrogen oxidation activity; i.e., it is oxygen-tolerant. Reactivation experiments show that two inactive states are formed by interaction with oxygen and both can be quickly (<150 s) reactivated. Analogous experiments, in which the interval of oxygen exposure is extended to 900 s, reveal that the response is highly temperature-dependent. At 25 °C, under sustained 1% O2/ 99% H2 exposure, the H2oxidation activity drops nearly to zero. However, at 80 °C, up to 32% of the enzyme's oxidation activity is retained. Reactivation of PfSHI following sustained exposure to oxygen occurs on a much longer time scale (tens of minutes), suggesting that a third inactive species predominates under these conditions. These results stand in contrast to the properties of oxygen-tolerant, group 1 [NiFe]-hydrogenases, which form a single state upon reaction with oxygen, and we propose that this new type of hydrogenase should be referred to as oxygen-resilient. Furthermore, PfSHI, like other group 3 [NiFe]-hydrogenases, does not possess the proximal [4Fe3S] cluster associated with the oxygen tolerance of some group 1 enzymes. Thus, a new mechanism is necessary to explain the observed oxygen tolerance in soluble, group 3 [NiFe]-hydrogenases, and we present a model integrating both electrochemical and spectroscopic results to define the relationships of these inactive states.
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Affiliation(s)
- Patrick Kwan
- Department of Chemistry and Biochemistry, Arizona State University , Tempe, Arizona 85287, United States
| | - Chelsea L McIntosh
- Department of Chemistry and Biochemistry, Arizona State University , Tempe, Arizona 85287, United States
| | - David P Jennings
- Department of Chemistry and Biochemistry, Arizona State University , Tempe, Arizona 85287, United States
| | - R Chris Hopkins
- Department of Biochemistry and Molecular Biology, The University of Georgia , Athens, Georgia 30602, United States
| | - Sanjeev K Chandrayan
- Department of Biochemistry and Molecular Biology, The University of Georgia , Athens, Georgia 30602, United States
| | - Chang-Hao Wu
- Department of Biochemistry and Molecular Biology, The University of Georgia , Athens, Georgia 30602, United States
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology, The University of Georgia , Athens, Georgia 30602, United States
| | - Anne K Jones
- Department of Chemistry and Biochemistry, Arizona State University , Tempe, Arizona 85287, United States
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26
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27
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Khusnutdinova JR, Milstein D. Metal-Ligand Cooperation. Angew Chem Int Ed Engl 2015; 54:12236-73. [DOI: 10.1002/anie.201503873] [Citation(s) in RCA: 783] [Impact Index Per Article: 87.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Indexed: 12/25/2022]
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28
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Kaiser M, Knör G. Synthesis, Characterization, and Reactivity of Functionalized Trinuclear Iron-Sulfur Clusters - A New Class of Bioinspired Hydrogenase Models. Eur J Inorg Chem 2015; 2015:4199-4206. [PMID: 26512211 PMCID: PMC4612652 DOI: 10.1002/ejic.201500574] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Indexed: 02/03/2023]
Abstract
The air- and moisture-stable iron-sulfur carbonyl clusters Fe3S2(CO)7(dppm) (1) and Fe3S2(CO)7(dppf) (2) carrying the bisphosphine ligands bis(diphenylphosphanyl)methane (dppm) and 1,1'-bis(diphenylphosphanyl)ferrocene (dppf) were prepared and fully characterized. Two alternative synthetic routes based on different thionation reactions of triiron dodecacarbonyl were tested. The molecular structures of the methylene-bridged compound 1 and the ferrocene-functionalized derivative 2 were determined by single-crystal X-ray diffraction. The catalytic reactivity of the trinuclear iron-sulfur cluster core for proton reduction in solution at low overpotential was demonstrated. These deeply colored bisphosphine-bridged sulfur-capped iron carbonyl systems are discussed as promising candidates for the development of new bioinspired model compounds of iron-based hydrogenases.
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Affiliation(s)
- Manuel Kaiser
- Institute of Inorganic Chemistry, Johannes Kepler University Linz (JKU) , Altenbergerstr. 69, 4040 Linz, Austria , http://www.anorganik.jku.at
| | - Günther Knör
- Institute of Inorganic Chemistry, Johannes Kepler University Linz (JKU) , Altenbergerstr. 69, 4040 Linz, Austria , http://www.anorganik.jku.at
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29
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Vedha SA, Velmurugan G, Jagadeesan R, Venuvanalingam P. Insights from the computational studies on the oxidized as-isolated state of [NiFeSe] hydrogenase from D. vulgaris Hildenborough. Phys Chem Chem Phys 2015. [PMID: 26205195 DOI: 10.1039/c5cp03071d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A density functional theory study of the active site structure and features of the oxygen tolerant [NiFeSe] Hase in the oxidized as-isolated state of the enzyme D. vulgaris Hildenborough (DvH) is reported here. The three conformers reported to be present in the X-ray structure (PDB ID: ) have been studied. The novel bidentate interchalcogen ligand (S-Se) in Conf-I of the [NiFeSe] Hase reported for the first time in hydrogenases (Hase) is found to be of donor-acceptor type with an uneven η(2) L → M σ-bond. The symmetry mismatch at the sp orbital of Se and at the dz(2) orbital of Ni has been identified to be the reason for the inability of Conf-II to convert to Conf-I. NBO analysis shows that the sulfinate ligand peculiar to the state stabilizes the active site through n →π* interactions. The results reveal that the isolated oxidized state of the [NiFeSe] Hase is significantly different from the well-known [NiFe] Hase.
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Affiliation(s)
- Swaminathan Angeline Vedha
- Theoretical and Computational Chemistry Laboratory, School of Chemistry, Bharathidasan University, Tiruchirappalli-620 024, India.
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30
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Wang WH, Ertem MZ, Xu S, Onishi N, Manaka Y, Suna Y, Kambayashi H, Muckerman JT, Fujita E, Himeda Y. Highly Robust Hydrogen Generation by Bioinspired Ir Complexes for Dehydrogenation of Formic Acid in Water: Experimental and Theoretical Mechanistic Investigations at Different pH. ACS Catal 2015. [DOI: 10.1021/acscatal.5b01090] [Citation(s) in RCA: 117] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Wan-Hui Wang
- School
of Petroleum and Chemical Engineering, Dalian University of Technology, Panjin 124221, China
| | - Mehmed Z. Ertem
- Chemistry
Department, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Shaoan Xu
- National Institute of Advanced Industrial Science and Technology, Tsukuba Central 5-1, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565 Japan
| | - Naoya Onishi
- National Institute of Advanced Industrial Science and Technology, Tsukuba Central 5-1, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565 Japan
| | - Yuichi Manaka
- National Institute of Advanced Industrial Science and Technology, Tsukuba Central 5-1, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565 Japan
- Japan Science and Technology Agency, CREST, 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012 Japan
| | - Yuki Suna
- National Institute of Advanced Industrial Science and Technology, Tsukuba Central 5-1, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565 Japan
| | - Hide Kambayashi
- National Institute of Advanced Industrial Science and Technology, Tsukuba Central 5-1, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565 Japan
| | - James T. Muckerman
- Chemistry
Department, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Etsuko Fujita
- Chemistry
Department, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Yuichiro Himeda
- National Institute of Advanced Industrial Science and Technology, Tsukuba Central 5-1, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565 Japan
- Japan Science and Technology Agency, CREST, 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012 Japan
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31
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Nakae T, Hirotsu M, Kinoshita I. Di- and Mononuclear Iron Complexes of N,C,S-Tridentate Ligands Containing an Aminopyridyl Group: Effect of the Pendant Amine Site on Catalytic Properties for Proton Reduction. Organometallics 2015. [DOI: 10.1021/acs.organomet.5b00366] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Toyotaka Nakae
- Graduate School of Science and ‡The OCU Advanced
Research Institute for Natural
Science and Technology (OCARINA), Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Masakazu Hirotsu
- Graduate School of Science and ‡The OCU Advanced
Research Institute for Natural
Science and Technology (OCARINA), Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Isamu Kinoshita
- Graduate School of Science and ‡The OCU Advanced
Research Institute for Natural
Science and Technology (OCARINA), Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
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32
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Mazzoni R, Gabiccini A, Cesari C, Zanotti V, Gualandi I, Tonelli D. Diiron Complexes Bearing Bridging Hydrocarbyl Ligands as Electrocatalysts for Proton Reduction. Organometallics 2015. [DOI: 10.1021/acs.organomet.5b00274] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Rita Mazzoni
- Dipartimento di Chimica Industriale “Toso Montanari”, Università di Bologna, Viale Risorgimento 4; 40136 Bologna, Italy
| | - Alberto Gabiccini
- Dipartimento di Chimica Industriale “Toso Montanari”, Università di Bologna, Viale Risorgimento 4; 40136 Bologna, Italy
| | - Cristiana Cesari
- Dipartimento di Chimica Industriale “Toso Montanari”, Università di Bologna, Viale Risorgimento 4; 40136 Bologna, Italy
| | - Valerio Zanotti
- Dipartimento di Chimica Industriale “Toso Montanari”, Università di Bologna, Viale Risorgimento 4; 40136 Bologna, Italy
| | - Isacco Gualandi
- Dipartimento di Chimica Industriale “Toso Montanari”, Università di Bologna, Viale Risorgimento 4; 40136 Bologna, Italy
| | - Domenica Tonelli
- Dipartimento di Chimica Industriale “Toso Montanari”, Università di Bologna, Viale Risorgimento 4; 40136 Bologna, Italy
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33
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Kaliakin DS, Zaari RR, Varganov SA. Effect of H2 Binding on the Nonadiabatic Transition Probability between Singlet and Triplet States of the [NiFe]-Hydrogenase Active Site. J Phys Chem A 2015; 119:1066-73. [DOI: 10.1021/jp510522z] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Danil S. Kaliakin
- Department
of Chemistry, University of Nevada, Reno, 1664 North Virginia Street, Reno, Nevada 89557-0216, United States
- Department
of Chemistry, Siberian Federal University, 79 Svobodnyi Prospect, Krasnoyarsk, Krasnoyarskiy kray 660041, Russia
| | - Ryan R. Zaari
- Department
of Chemistry, University of Nevada, Reno, 1664 North Virginia Street, Reno, Nevada 89557-0216, United States
| | - Sergey A. Varganov
- Department
of Chemistry, University of Nevada, Reno, 1664 North Virginia Street, Reno, Nevada 89557-0216, United States
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34
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Santo K, Hirotsu M, Kinoshita I. Formation, reactivity and redox properties of carbon- and sulfur-bridged diiron complexes derived from dibenzothienyl Schiff bases: effect of N,N- and N,P-chelating moieties. Dalton Trans 2015; 44:4155-66. [DOI: 10.1039/c4dt03422h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Redox properties of C,S-bridged diiron complexes were controlled by using dibenzothienyl Schiff base precursors with an N,N- or N,P-chelating moiety.
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Affiliation(s)
- Kiyokazu Santo
- Division of Molecular Materials Science
- Graduate School of Science
- Osaka City University
- Sumiyoshi-ku
- Japan
| | - Masakazu Hirotsu
- Division of Molecular Materials Science
- Graduate School of Science
- Osaka City University
- Sumiyoshi-ku
- Japan
| | - Isamu Kinoshita
- Division of Molecular Materials Science
- Graduate School of Science
- Osaka City University
- Sumiyoshi-ku
- Japan
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35
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Zuzek AA, Parkin G. Oxidative addition of SiH4and GeH4to Ir(PPh3)2(CO)Cl: structural and spectroscopic evidence for the formation of products derived from cis oxidative addition. Dalton Trans 2015; 44:2801-8. [DOI: 10.1039/c4dt03363a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Oxidative addition of SiH4and GeH4to Vaska's compound occurs in acismanner but two isomers can be obtained according to whether H istransto CO or Cl. Only the isomer with Htransto CO is observed for SiH4, whereas both isomers are observed for GeH4.
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Affiliation(s)
| | - Gerard Parkin
- Department of Chemistry
- Columbia University
- New York
- USA
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36
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Chouffai D, Capon JF, De Gioia L, Pétillon FY, Schollhammer P, Talarmin J, Zampella G. A Diferrous Dithiolate as a Model of the Elusive Hoxinact State of the [FeFe] Hydrogenases: An Electrochemical and Theoretical Dissection of Its Redox Chemistry. Inorg Chem 2014; 54:299-311. [DOI: 10.1021/ic5024746] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Dounia Chouffai
- UMR CNRS 6521 Chimie, Electrochimie Moléculaires
et Chimie Analytique, Université de Bretagne Occidentale, UFR Sciences et Techniques, CS 93837, 29238 Brest-Cedex 3, France
| | - Jean-François Capon
- UMR CNRS 6521 Chimie, Electrochimie Moléculaires
et Chimie Analytique, Université de Bretagne Occidentale, UFR Sciences et Techniques, CS 93837, 29238 Brest-Cedex 3, France
| | - Luca De Gioia
- Department
of Biotechnology and Bioscience, University of Milano-Bicocca, Piazza
della Scienza 2, 20126 Milan, Italy
| | - François Y. Pétillon
- UMR CNRS 6521 Chimie, Electrochimie Moléculaires
et Chimie Analytique, Université de Bretagne Occidentale, UFR Sciences et Techniques, CS 93837, 29238 Brest-Cedex 3, France
| | - Philippe Schollhammer
- UMR CNRS 6521 Chimie, Electrochimie Moléculaires
et Chimie Analytique, Université de Bretagne Occidentale, UFR Sciences et Techniques, CS 93837, 29238 Brest-Cedex 3, France
| | - Jean Talarmin
- UMR CNRS 6521 Chimie, Electrochimie Moléculaires
et Chimie Analytique, Université de Bretagne Occidentale, UFR Sciences et Techniques, CS 93837, 29238 Brest-Cedex 3, France
| | - Giuseppe Zampella
- Department
of Biotechnology and Bioscience, University of Milano-Bicocca, Piazza
della Scienza 2, 20126 Milan, Italy
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37
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Zamorano A, Rendón N, López-Serrano J, Valpuesta JEV, Álvarez E, Carmona E. Dihydrogen Catalysis of the Reversible Formation and Cleavage of CH and NH Bonds of Aminopyridinate Ligands Bound to (η5-C5Me5)IrIII. Chemistry 2014; 21:2576-87. [DOI: 10.1002/chem.201405340] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Indexed: 11/06/2022]
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38
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Beaume L, Clémancey M, Blondin G, Greco C, Pétillon FY, Schollhammer P, Talarmin J. New Systematic Route to Mixed-Valence Triiron Clusters Derived from Dinuclear Models of the Active Site of [Fe–Fe]-Hydrogenases. Organometallics 2014. [DOI: 10.1021/om5010594] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Laetitia Beaume
- UMR CNRS 6521,
Université de Bretagne Occidentale, 6 Avenue Le Gorgeu, C.S. 93837, 29238 Brest, France
| | - Martin Clémancey
- CEA, iRTSV-LCBM-PMB, 17 rue des Martyrs, 38000 Grenoble, France
- Univ. Grenoble
Alpes,
iRTSV-LCBM-PMB, 17 rue des Martyrs, 38000 Grenoble, France
| | - Geneviève Blondin
- CEA, iRTSV-LCBM-PMB, 17 rue des Martyrs, 38000 Grenoble, France
- CNRS, iRTSV-LCBM-PMB, 17 rue des Martyrs, 38000 Grenoble, France
| | - Claudio Greco
- Department
of Earth and Environmental Sciences, University of Milano-Bicocca, Piazza
della Scienza, 1, 20126 Milan, Italy
| | - François Y. Pétillon
- UMR CNRS 6521,
Université de Bretagne Occidentale, 6 Avenue Le Gorgeu, C.S. 93837, 29238 Brest, France
| | - Philippe Schollhammer
- UMR CNRS 6521,
Université de Bretagne Occidentale, 6 Avenue Le Gorgeu, C.S. 93837, 29238 Brest, France
| | - Jean Talarmin
- UMR CNRS 6521,
Université de Bretagne Occidentale, 6 Avenue Le Gorgeu, C.S. 93837, 29238 Brest, France
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39
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Sattler A, Zuzek AA, Parkin G. Molecular structure of W(PMe3)3H6 in the solid state and in solution. Inorganica Chim Acta 2014. [DOI: 10.1016/j.ica.2014.07.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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40
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Asatryan R, Ruckenstein E. Dihydrogen Catalysis: A Remarkable Avenue in the Reactivity of Molecular Hydrogen. CATALYSIS REVIEWS-SCIENCE AND ENGINEERING 2014. [DOI: 10.1080/01614940.2014.953356] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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41
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Ghosh S, Hogarth G, Hollingsworth N, Holt KB, Kabir SE, Sanchez BE. Hydrogenase biomimetics: Fe2(CO)4(μ-dppf)(μ-pdt) (dppf = 1,1'-bis(diphenylphosphino)ferrocene) both a proton-reduction and hydrogen oxidation catalyst. Chem Commun (Camb) 2014; 50:945-7. [PMID: 24301100 DOI: 10.1039/c3cc46456c] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Fe2(CO)4(μ-dppf)(μ-pdt) catalyses the conversion of protons and electrons into hydrogen and also the reverse reaction thus mimicing both types of binuclear hydrogenase enzymes.
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Affiliation(s)
- Shishir Ghosh
- Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK.
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42
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Hirotsu M, Santo K, Tsuboi C, Kinoshita I. Diiron Carbonyl Complexes Bearing an N,C,S-Pincer Ligand: Reactivity toward Phosphines, Heterolytic Fe–Fe Cleavage, and Electrocatalytic Proton Reduction. Organometallics 2014. [DOI: 10.1021/om500558h] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Masakazu Hirotsu
- Graduate School of Science and ‡The OCU Advanced
Research Institute for Natural
Science and Technology (OCARINA), Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Kiyokazu Santo
- Graduate School of Science and ‡The OCU Advanced
Research Institute for Natural
Science and Technology (OCARINA), Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Chiaki Tsuboi
- Graduate School of Science and ‡The OCU Advanced
Research Institute for Natural
Science and Technology (OCARINA), Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Isamu Kinoshita
- Graduate School of Science and ‡The OCU Advanced
Research Institute for Natural
Science and Technology (OCARINA), Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
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43
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Toda T, Kuwata S, Ikariya T. Unsymmetrical pincer-type ruthenium complex containing β-protic pyrazole and N-heterocyclic carbene arms: comparison of Brønsted acidity of NH groups in second coordination sphere. Chemistry 2014; 20:9539-42. [PMID: 24965086 DOI: 10.1002/chem.201403179] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Indexed: 12/30/2022]
Abstract
A reaction of a 2-(imidazol-1-yl)methyl-6-(pyrazol-3-yl)pyridine with [RuCl2 (PPh3 )3 ] resulted in tautomerization of the imidazole unit to afford the unsymmetrical pincer-type ruthenium complex 2 containing a protic pyrazole and N-heterocyclic carbene (NHC) arms. Deprotonation of 2 with one equivalent of a base led to the formation of the NHC-pyrazolato complex 3, indicating that the protic NHC arm is less acidic. When 2 was treated with two equivalents of a base under H2 or in 2-propanol, the hydrido complex 4 containing protic NHC and pyrazolato groups was obtained through metal-ligand cooperation.
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Affiliation(s)
- Tatsuro Toda
- Department of Applied Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552 (Japan), Fax: (+81) 3-5734-2637
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44
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Broderick JB, Byer AS, Duschene KS, Duffus BR, Betz JN, Shepard EM, Peters JW. H-cluster assembly during maturation of the [FeFe]-hydrogenase. J Biol Inorg Chem 2014; 19:747-57. [PMID: 24972661 DOI: 10.1007/s00775-014-1168-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 06/03/2014] [Indexed: 11/28/2022]
Abstract
The organometallic H-cluster at the active site of the [FeFe]-hydrogenase serves as the site of reversible binding and reduction of protons to produce H2. The H-cluster is unique in biology, and consists of a 2Fe subcluster tethered to a typical [4Fe-4S] cluster by a single cysteine ligand. The remaining ligands to the 2Fe subcluster include three carbon monoxides, two cyanides, and a dithiomethylamine. This mini-review will focus on the significant advances in recent years in understanding the pathway for H-cluster biosynthesis, as well as the structures, roles, and mechanisms of the three enzymes directly involved.
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Affiliation(s)
- Joan B Broderick
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT, 59717, USA,
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45
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Vedha SA, Solomon RV, Venuvanalingam P. Atomic partitioning of M-H2 bonds in [NiFe] hydrogenase--a test case of concurrent binding. Phys Chem Chem Phys 2014; 16:10698-707. [PMID: 24756140 DOI: 10.1039/c4cp00526k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The possibility of simultaneous addition of η(2)-H2 to both the metals (Ni and Fe) in the active site of the as isolated state of the enzyme (Ni-SI) is examined here by an atom-by-atom electronic energy partitioning based on the QTAIM method. Results show that the 4LS state prefers H2 removal than addition. Destabilization of the atomic basins of the thiolate bridges and decrease of the electrophilicity of the Fe and Ni, resulting in poor back donation to the CO ligand, are the bottlenecks that hamper dihydrogen activation simultaneously. The study helps to understand why such states are seldom accessed in the activation of dihydrogen. Moreover, Ni has been found to be the natural choice for the dihydrogen binding.
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Affiliation(s)
- Swaminathan Angeline Vedha
- Theoretical & Computational Chemistry Laboratory, School of Chemistry, Bharathidasan University, Tiruchirappalli 24, India.
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46
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Ogienko MA, Pushkarevsky NA, Smolentsev AI, Nadolinny VA, Ketkov SY, Konchenko SN. Metal- and Ligand-Supported Reduction of the {Fe2S2} Cluster as a Path to Formation of Molecular Group 13 Element Complexes {Fe2S2M} (M = Al, Ga). Organometallics 2014. [DOI: 10.1021/om401237x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Mikhail A. Ogienko
- Nikolaev Institute
of Inorganic Chemistry, Siberian Branch of RAS, Akad. Lavrentieva
Avenue 3, 630090 Novosibirsk, Russia
| | - Nikolay A. Pushkarevsky
- Nikolaev Institute
of Inorganic Chemistry, Siberian Branch of RAS, Akad. Lavrentieva
Avenue 3, 630090 Novosibirsk, Russia
- Department of Natural Sciences, Novosibirsk State University, Pirogova
St. 2, 630090 Novosibirsk, Russia
| | - Anton I. Smolentsev
- Nikolaev Institute
of Inorganic Chemistry, Siberian Branch of RAS, Akad. Lavrentieva
Avenue 3, 630090 Novosibirsk, Russia
| | - Vladimir A. Nadolinny
- Nikolaev Institute
of Inorganic Chemistry, Siberian Branch of RAS, Akad. Lavrentieva
Avenue 3, 630090 Novosibirsk, Russia
| | - Sergey Yu. Ketkov
- G. A. Razuvaev Institute of Organometallic Chemistry, Tropinina St. 49, 603950 Nizhny Novgorod, Russia
- Department of Chemistry, N. I. Lobachevsky State University of Nizhny Novgorod, 23 Gagarin Avenue, 603950 Nizhny Novgorod, Russia
| | - Sergey N. Konchenko
- Nikolaev Institute
of Inorganic Chemistry, Siberian Branch of RAS, Akad. Lavrentieva
Avenue 3, 630090 Novosibirsk, Russia
- Department of Natural Sciences, Novosibirsk State University, Pirogova
St. 2, 630090 Novosibirsk, Russia
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47
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Rivada-Wheelaghan O, Roselló-Merino M, Ortuño MA, Vidossich P, Gutiérrez-Puebla E, Lledós A, Conejero S. Reactivity of coordinatively unsaturated bis(N-heterocyclic carbene) Pt(II) complexes toward H(2). Crystal structure of a 14-electron Pt(II) hydride complex. Inorg Chem 2014; 53:4257-68. [PMID: 24716606 DOI: 10.1021/ic500705t] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The reactivity toward H2 of coordinatively unsaturated Pt(II) complexes, stabilized by N-heterocyclic carbene (NHC) ligands, is herein analyzed. The cationic platinum complexes [Pt(NHC')(NHC)](+) (where NHC' stands for a cyclometalated NHC ligand) react very fast with H2 at room temperature, leading to hydrogenolysis of the Pt-CH2 bond and concomitant formation of hydride derivatives [PtH(NHC)2](+) or hydrido-dihydrogen complexes [PtH(H2)(NHC)2](+). The latter species release H2 when these compounds are subjected to vacuum. The X-ray structure of complex [PtH(IPr)2][SbF6] revealed its unsaturated nature, exhibiting a true T-shaped structure without stabilization by agostic interactions. Density functional theory calculations indicate that the binding and reaction of H2 in complexes [PtH(H2)(NHC)2](+) is more favored for derivatives bearing aryl-substituted NHCs (IPr, 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene and IMes = 1,3-dimesityl-1,3-dihydro-2H-imidazol-2-ylidene) than for those containing tert-butyl groups (I(t)Bu). This outcome is related to the higher close-range steric effects of the I(t)Bu ligands. Accordingly, H/D exchange reactions between hydrides [PtH(NHC)2](+) and D2 take place considerably faster for IPr and IMes* derivatives than for I(t)Bu ones. The reaction mechanisms for both H2 addition and H/D exchange processes depend on the nature of the NHC ligand, operating through oxidative addition transition states in the case of IPr and IMes* or by a σ-complex assisted-metathesis mechanism in the case of I(t)Bu.
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Affiliation(s)
- Orestes Rivada-Wheelaghan
- Departamento de Química Inorgánica, CSIC and Universidad de Sevilla, Instituto de Investigaciones Químicas (IIQ) , Avda. Américo Vespucio 49, 41092, Sevilla, Spain
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48
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Riener K, Haslinger S, Raba A, Högerl MP, Cokoja M, Herrmann WA, Kühn FE. Chemistry of Iron N-Heterocyclic Carbene Complexes: Syntheses, Structures, Reactivities, and Catalytic Applications. Chem Rev 2014; 114:5215-72. [DOI: 10.1021/cr4006439] [Citation(s) in RCA: 329] [Impact Index Per Article: 32.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
| | | | | | - Manuel P. Högerl
- KAUST Catalysis Center, Division of Physical Sciences & Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
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49
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Dub PA, Henson NJ, Martin RL, Gordon JC. Unravelling the mechanism of the asymmetric hydrogenation of acetophenone by [RuX2(diphosphine)(1,2-diamine)] catalysts. J Am Chem Soc 2014; 136:3505-21. [PMID: 24524727 DOI: 10.1021/ja411374j] [Citation(s) in RCA: 184] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The mechanism of catalytic hydrogenation of acetophenone by the chiral complex trans-[RuCl2{(S)-binap}{(S,S)-dpen}] and KO-t-C4H9 in propan-2-ol is revised on the basis of DFT computations carried out in dielectric continuum and the most recent experimental observations. The results of these collective studies suggest that neither a six-membered pericyclic transition state nor any multibond concerted transition states are involved. Instead, a hydride moiety is transferred in an outer-sphere manner to afford an ion-pair, and the corresponding transition state is both enantio- and rate-determining. Heterolytic dihydrogen cleavage proceeds neither by a (two-bond) concerted, four-membered transition state, nor by a (three-bond) concerted, six-membered transition state mediated by a solvent molecule. Instead, cleavage of the H-H bond is achieved via deprotonation of the η(2)-H2 ligand within a cationic Ru complex by the chiral conjugate base of (R)-1-phenylethanol. Thus, protonation of the generated (R)-1-phenylethoxide anion originates from the η(2)-H2 ligand of the cationic Ru complex and not from NH protons of a neutral Ru trans-dihydride complex, as initially suggested within the framework of a metal-ligand bifunctional mechanism. Detailed computational analysis reveals that the 16e(-) Ru amido complex [RuH{(S)-binap}{(S,S)-HN(CHPh)2NH2}] and the 18e(-) Ru alkoxo complex trans-[RuH{OCH(CH3)(R)}{(S)-binap}{(S,S)-dpen}] (R = CH3 or C6H5) are not intermediates within the catalytic cycle, but rather are off-loop species. The accelerative effect of KO-t-C4H9 is explained by the reversible formation of the potassium amidato complexes trans-[RuH2{(S)-binap}{(S,S)-N(K)H(CHPh)2NH2}] or trans-[RuH2{(S)-binap}{(S,S)-N(K)H(CHPh)2NH(K)}]. The three-dimensional (3D) cavity observed within these molecules results in a chiral pocket stabilized via several different noncovalent interactions, including neutral and ionic hydrogen bonding, cation-π interactions, and π-π stacking interactions. Cooperatively, these interactions modify the catalyst structure, in turn lowering the relative activation barrier of hydride transfer by ~1-2 kcal mol(-1) and the following H-H bond cleavage by ~10 kcal mol(-1), respectively. A combined computational study and analysis of recent experimental data of the reaction pool results in new mechanistic insight into the catalytic cycle for hydrogenation of acetophenone by Noyori's catalyst, in the presence or absence of KO-t-C4H9.
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Affiliation(s)
- Pavel A Dub
- Chemistry Division, MS J582, and ‡Theoretical Division, MS B268, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
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50
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