1
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Nazemi A, Steeves AH, Kastner DW, Kulik HJ. Influence of the Greater Protein Environment on the Electrostatic Potential in Metalloenzyme Active Sites: The Case of Formate Dehydrogenase. J Phys Chem B 2022; 126:4069-4079. [PMID: 35609244 DOI: 10.1021/acs.jpcb.2c02260] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The Mo/W-containing metalloenzyme formate dehydrogenase (FDH) is an efficient and selective natural catalyst that reversibly converts CO2 to formate under ambient conditions. In this study, we investigate the impact of the greater protein environment on the electrostatic potential (ESP) of the active site. To model the enzyme environment, we used a combination of classical molecular dynamics and multiscale quantum-mechanical (QM)/molecular-mechanical (MM) simulations. We leverage charge shift analysis to systematically construct QM regions and analyze the electronic environment of the active site by evaluating the degree of charge transfer between the core active site and the protein environment. The contribution of the terminal chalcogen ligand to the ESP of the metal center is substantial and dependent on the chalcogen identity, with similar, less negative ESPs for Se and S terminal chalcogens in comparison to O regardless of whether the metal is Mo or W. The orientation of the side chains and conformations of the cofactor also affect the ESP, highlighting the importance of sampling dynamic fluctuations in the protein. Overall, our observations suggest that the terminal chalcogen ligand identity plays an important role in the enzymatic activity of FDH, suggesting opportunities for a rational bioinspired catalyst design.
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Affiliation(s)
- Azadeh Nazemi
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Adam H Steeves
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - David W Kastner
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Heather J Kulik
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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2
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Liu M, Nazemi A, Taylor MG, Nandy A, Duan C, Steeves AH, Kulik HJ. Large-Scale Screening Reveals That Geometric Structure Matters More Than Electronic Structure in the Bioinspired Catalyst Design of Formate Dehydrogenase Mimics. ACS Catal 2021. [DOI: 10.1021/acscatal.1c04624] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Mingjie Liu
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Azadeh Nazemi
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Michael G. Taylor
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Aditya Nandy
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Chenru Duan
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Adam H. Steeves
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Heather J. Kulik
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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3
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Li Y, Gomez-Mingot M, Fogeron T, Fontecave M. Carbon Dioxide Reduction: A Bioinspired Catalysis Approach. Acc Chem Res 2021; 54:4250-4261. [PMID: 34761916 DOI: 10.1021/acs.accounts.1c00461] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
While developed in a number of directions, bioinspired catalysis has been explored only very recently for CO2 reduction, a challenging reaction of prime importance in the context of the energetic transition to be built up. This approach is particularly relevant because nature teaches us that CO2 reduction is possible, with low overpotentials, high rates, and large selectivity, and gives us unique clues to design and discover new interesting molecular catalysts. Indeed, on the basis of our relatively advanced understanding of the structures and mechanisms of the active sites of fascinating metalloenzymes such as formate dehydrogenases (FDHs) and CO dehydrogenases (CODHs), it is possible to design original, active, selective, and stable molecular catalysts using the bioinspired approach. These metalloenzymes use fascinating metal centers: in FDHs, a Mo(W) mononuclear ion is coordinated by four sulfur atoms provided by a specific organic ligand, molybdopterin (MPT), containing a pyranopterin heterocycle (composed of a pyran ring fused with a pterin unit) and two sulfhydryl groups for metal chelation; in CODHs, catalytic activity depends on either a unique nickel-iron-sulfur cluster or a dinuclear Mo-Cu complex in which the Mo ion is chelated by an MPT ligand. As a consequence, the novel class of catalysts, designed by bioinspiration, consists of mononuclear Mo, W, and Ni and as well as dinuclear Mo-Cu and Ni-Fe complexes in which the metal ions are coordinated by sulfur ligands, more specifically, dithiolene chelates mimicking the natural MPT cofactor. In general, their activity is evaluated in electrochemical systems (cyclic voltammetry and bulk electrolysis) or in photochemical systems (in the presence of a photosensitizer and a sacrificial electron donor) in solution. This research is multidisciplinary because it implies detailed biochemical, functional, and structural characterization of the inspiring enzymes together with synthetic organic and organometallic chemistry and molecular catalysis studies. The most important achievements in this direction, starting from the first report of a catalytically active biomimetic bis-dithiolene-Mo complex in 2015, are discussed in this Account, highlighting the challenging issues associated with synthesis of such sophisticated ligands and molecular catalysts as well as the complexity of reaction mechanisms. While the very first active biomimetic catalysts require further improvement, in terms of performance, they set the stage in which molecular chemistry and enzymology can synergistically cooperate for a better understanding of why nature has selected these sites and for developing highly active catalysts.
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Affiliation(s)
- Yun Li
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05, France
| | - Maria Gomez-Mingot
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05, France
| | - Thibault Fogeron
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05, France
| | - Marc Fontecave
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05, France
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4
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Seo J, Shearer J, Williard PG, Kim E. Reactivity of a biomimetic W(iv) bis-dithiolene complex with CO2 leading to formate production and structural rearrangement. Dalton Trans 2019; 48:17441-17444. [DOI: 10.1039/c9dt03906f] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A mononuclear W(iv) bis-dithiolene complex reduces CO2 to formate while generating a dinuclear W(v) complex.
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Affiliation(s)
- Junhyeok Seo
- Department of Chemistry
- Gwangju Institute of Science and Technology
- Gwangju 61005
- Republic of Korea
| | - Jason Shearer
- Department of Chemistry
- Trinity University
- San Antonio
- USA
| | | | - Eunsuk Kim
- Department of Chemistry
- Brown University
- Providence
- USA
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5
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Fogeron T, Retailleau P, Chamoreau L, Li Y, Fontecave M. Pyranopterin Related Dithiolene Molybdenum Complexes as Homogeneous Catalysts for CO
2
Photoreduction. Angew Chem Int Ed Engl 2018; 57:17033-17037. [DOI: 10.1002/anie.201809084] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 10/19/2018] [Indexed: 01/14/2023]
Affiliation(s)
- Thibault Fogeron
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS Collège de France, Université Paris Sorbonne 11 Place Marcelin Berthelot 75231 Paris Cedex 05 France
| | - Pascal Retailleau
- Institut de Chimie des Substances Naturelles, CNRS UPR 2301 Université Paris-Saclay 1, av.de la Terrasse 91198 Gif-sur-Yvette France
| | - Lise‐Marie Chamoreau
- Sorbonne Universités Université Paris Sorbonne Institut Parisien de Chimie Moléculaire, UMR 8232 CNRS 4 place Jussieu 75252 Paris Cedex 5 France
| | - Yun Li
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS Collège de France, Université Paris Sorbonne 11 Place Marcelin Berthelot 75231 Paris Cedex 05 France
| | - Marc Fontecave
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS Collège de France, Université Paris Sorbonne 11 Place Marcelin Berthelot 75231 Paris Cedex 05 France
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6
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Fogeron T, Retailleau P, Chamoreau L, Li Y, Fontecave M. Pyranopterin Related Dithiolene Molybdenum Complexes as Homogeneous Catalysts for CO
2
Photoreduction. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201809084] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Thibault Fogeron
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS Collège de France, Université Paris Sorbonne 11 Place Marcelin Berthelot 75231 Paris Cedex 05 France
| | - Pascal Retailleau
- Institut de Chimie des Substances Naturelles, CNRS UPR 2301 Université Paris-Saclay 1, av.de la Terrasse 91198 Gif-sur-Yvette France
| | - Lise‐Marie Chamoreau
- Sorbonne Universités Université Paris Sorbonne Institut Parisien de Chimie Moléculaire, UMR 8232 CNRS 4 place Jussieu 75252 Paris Cedex 5 France
| | - Yun Li
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS Collège de France, Université Paris Sorbonne 11 Place Marcelin Berthelot 75231 Paris Cedex 05 France
| | - Marc Fontecave
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS Collège de France, Université Paris Sorbonne 11 Place Marcelin Berthelot 75231 Paris Cedex 05 France
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7
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Nicolaou KC, Li R, Lu Z, Pitsinos EN, Alemany LB, Aujay M, Lee C, Sandoval J, Gavrilyuk J. Streamlined Total Synthesis of Shishijimicin A and Its Application to the Design, Synthesis, and Biological Evaluation of Analogues thereof and Practical Syntheses of PhthNSSMe and Related Sulfenylating Reagents. J Am Chem Soc 2018; 140:12120-12136. [PMID: 30216054 DOI: 10.1021/jacs.8b06955] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Shishijimicin A is a scarce marine natural product with highly potent cytotoxicities, making it a potential payload or a lead compound for designed antibody-drug conjugates. Herein, we describe an improved total synthesis of shishijimicin A and the design, synthesis, and biological evaluation of a series of analogues. Equipped with appropriate functionalities for linker attachment, a number of these analogues exhibited extremely potent cytotoxicities for the intended purposes. The synthetic strategies and tactics developed and employed in these studies included improved preparation of previously known and new sulfenylating reagents such as PhthNSSMe and related compounds.
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Affiliation(s)
| | | | | | - Emmanuel N Pitsinos
- Laboratory of Natural Products Synthesis & Bioorganic Chemistry, Institute of Nanoscience and Nanotechnology , National Centre for Scientific Research "Demokritos" , 153 10 Agia Paraskevi , Greece
| | | | - Monette Aujay
- AbbVie Stemcentrx, LLC , 450 East Jamie Court , South San Francisco , California 94080 , United States
| | - Christina Lee
- AbbVie Stemcentrx, LLC , 450 East Jamie Court , South San Francisco , California 94080 , United States
| | - Joseph Sandoval
- AbbVie Stemcentrx, LLC , 450 East Jamie Court , South San Francisco , California 94080 , United States
| | - Julia Gavrilyuk
- AbbVie Stemcentrx, LLC , 450 East Jamie Court , South San Francisco , California 94080 , United States
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8
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Okamura TA, Omi Y, Hirano Y, Onitsuka K. Comparative studies on the contribution of NHS hydrogen bonds in tungsten and molybdenum benzenedithiolate complexes. Dalton Trans 2018; 45:15651-15659. [PMID: 27722343 DOI: 10.1039/c6dt02250b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of monooxotungsten(iv) and dioxotungsten(vi) benzenedithiolates, (NEt4)2[WIVO(1,2-S2-3-RCONHC6H3)2] (1-W; R = CH3 (a), t-Bu (b), or CF3 (c)) and (NEt4)2[WVIO2(1,2-S2-3-RCONHC6H3)2] (2-W), were synthesized and compared with the corresponding molybdenum analogues. Single crystals of trans-1b-W were successfully obtained, and the crystal structure was determined by X-ray analysis although 1b-Mo could not be crystallized. The NHS hydrogen bonds shifted the potential of the W(iv/v) redox couple to more positive values, and the strength of the hydrogen bond and the positive shift value were strongly correlated. The hydrogen bonds in both 1-W and 2-W were weaker than those in the corresponding molybdenum analogues; however, the effect of the hydrogen bonds on the redox potential was greater in 1-W.
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Affiliation(s)
- Taka-Aki Okamura
- Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
| | - Yui Omi
- Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
| | - Yasunori Hirano
- Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
| | - Kiyotaka Onitsuka
- Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
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9
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Synthesis and solution structure of desoxotungsten(IV) and monooxotungsten(VI) benzenedithiolate complexes containing two intramolecular NH⋯S hydrogen bonds. Inorganica Chim Acta 2017. [DOI: 10.1016/j.ica.2017.08.036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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10
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Reschke S, Mebs S, Sigfridsson-Clauss KGV, Kositzki R, Leimkühler S, Haumann M. Protonation and Sulfido versus Oxo Ligation Changes at the Molybdenum Cofactor in Xanthine Dehydrogenase (XDH) Variants Studied by X-ray Absorption Spectroscopy. Inorg Chem 2017; 56:2165-2176. [DOI: 10.1021/acs.inorgchem.6b02846] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Stefan Reschke
- Institut für
Biochemie und Biologie, Molekulare Enzymologie, Universität Potsdam, 14476 Potsdam, Germany
| | - Stefan Mebs
- Institut für Experimentalphysik, Freie Universität Berlin, 14195 Berlin, Germany
| | | | - Ramona Kositzki
- Institut für Experimentalphysik, Freie Universität Berlin, 14195 Berlin, Germany
| | - Silke Leimkühler
- Institut für
Biochemie und Biologie, Molekulare Enzymologie, Universität Potsdam, 14476 Potsdam, Germany
| | - Michael Haumann
- Institut für Experimentalphysik, Freie Universität Berlin, 14195 Berlin, Germany
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11
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Ghosh AC, Samuel PP, Schulzke C. Synthesis, characterization and oxygen atom transfer reactivity of a pair of Mo(iv)O- and Mo(vi)O2-enedithiolate complexes – a look at both ends of the catalytic transformation. Dalton Trans 2017; 46:7523-7533. [DOI: 10.1039/c7dt01470h] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel pair of mono-oxo and di-oxo bis-dithiolene molybdenum complexes were synthesized, characterized and catalytically investigated as models for a molybdenum dependent oxidoreductase.
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Affiliation(s)
- Ashta C. Ghosh
- Institute of Condensed Matter and Nanosciences
- Molecules
- Solids and Reactivity (IMCN/MOST)
- Université catholique de Louvain
- 1348 Louvain-la-Neuve
| | - Prinson P. Samuel
- Universität Göttingen
- Institut für Anorganische Chemie
- 37077 Göttingen
- Germany
| | - Carola Schulzke
- Institut für Biochemie
- Ernst-Moritz-Arndt-Universitat Greifswald
- 17487 Greifswald
- Germany
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12
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Porcher JP, Fogeron T, Gomez-Mingot M, Chamoreau LM, Li Y, Fontecave M. Synthesis and Reactivity of a Bio-inspired Dithiolene Ligand and its Mo Oxo Complex. Chemistry 2016; 22:4447-53. [PMID: 26880579 DOI: 10.1002/chem.201504373] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Indexed: 12/15/2022]
Abstract
An original synthesis of the fused pyranoquinoxaline dithiolene ligand qpdt(2-) is discussed in detail. The most intriguing step is the introduction of the dithiolene moiety by Pd-catalyzed carbon-sulfur coupling. The corresponding Mo(IV)O complex (Bu4N)2 [MoO(qpdt)2] (2) underwent reversible protonation in a strongly acidic medium and remained stable under anaerobic conditions. Besides, 2 was found to be very sensitive towards oxygen, as upon oxidation it formed a planar dithiin derivative. Moreover, the qpdt(2-) ligand in the presence of [MoCl4 (tBuNC)2] formed a tetracyclic structure. The products resulting from the unique reactivity of qpdt(2-) were characterized by X-ray diffraction, mass spectrometry, NMR spectroscopy, UV/Vis spectroscopy, and electrochemistry. Plausible mechanisms for the formation of these products are also proposed.
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Affiliation(s)
- Jean-Philippe Porcher
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231, Paris CEDEX 05, France
| | - Thibault Fogeron
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231, Paris CEDEX 05, France
| | - Maria Gomez-Mingot
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231, Paris CEDEX 05, France
| | - Lise-Marie Chamoreau
- Sorbonne Universités, UPMC Université Paris 6, Institut Parisien de Chimie Moléculaire, UMR 8232 CNRS, 4 Place Jussieu, 75252, Paris CEDEX 05, France
| | - Yun Li
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231, Paris CEDEX 05, France.
| | - Marc Fontecave
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231, Paris CEDEX 05, France.
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13
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Okamura TA, Okamura ATA, Omi Y, Fujii M, Tatsumi M, Onitsuka K. Significant differences of monooxotungsten(IV) and dioxotungsten(VI) benzenedithiolates containing two intramolecular NHS hydrogen bonds from molybdenum analogues. Dalton Trans 2015; 44:18090-100. [PMID: 26417921 DOI: 10.1039/c5dt03278d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A monooxotungsten(iv) benzenedithiolate complex containing two intramolecular NHS hydrogen bonds, (NEt4)2[W(IV)O(1,2-S2-3-t-BuNHCOC6H3)2] (1-W), was synthesized via a ligand-exchange reaction between a new starting complex, (NEt4)2[W(IV)O(SC6F5)4], and a partially deprotonated dithiol. When dithiol was used in solution, the oxo ligand was protonated and removed to afford (NEt4)2[W(IV)(1,2-S2-3-t-BuNHCOC6H3)3]. The trans isomer, trans-1-W, was crystallized, and the molecular structure was determined via X-ray analysis. Trans-1-W was gradually isomerized by heating it in solution and it eventually achieved an approximately 1 : 1 mixture of trans/cis isomers after 48 days. However, a slightly excess amount of trans isomer remained, so the isomerization rate was considerably slower than that of the molybdenum analogue. In the presence of NEt4BH4, deuteration of the NH protons was observed in acetonitrile-d3. The oxidation of both trans- and cis-1-W by Me3NO afforded the corresponding dioxotungsten(vi) complex, (NEt4)2[W(VI)O2(1,2-S2-3-t-BuNHCOC6H3)2] (2-W), as a single isomer. The contributions of the NHS hydrogen bonds to the bond distances, vibrational data, and electrochemical properties are described via comparisons with their molybdenum analogues. The results of this comparative study yielded insights into both tungsten and molybdenum enzymes.
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Affiliation(s)
| | - A Taka-Aki Okamura
- Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
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14
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Porcher JP, Fogeron T, Gomez-Mingot M, Derat E, Chamoreau LM, Li Y, Fontecave M. A Bioinspired Molybdenum Complex as a Catalyst for the Photo- and Electroreduction of Protons. Angew Chem Int Ed Engl 2015; 54:14090-3. [PMID: 26404460 DOI: 10.1002/anie.201505607] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 07/18/2015] [Indexed: 12/25/2022]
Abstract
A molybdenum-dithiolene-oxo complex was prepared as a model of some active sites of Mo/W-dependent enzymes. The ligand, a quinoxaline-pyran-fused dithiolene, mimics molybdopterin present in these active sites. For the first time, this type of complex was shown to be active as a catalyst for the photoreduction of protons with excellent turnover numbers (500) and good stability in aqueous/organic media and for the electroreduction of protons in acetonitrile with remarkable rate constants (1030 s(-1) at -1.3 V versus Ag/AgCl). DFT calculations provided insight into the catalytic cycle of the reaction, suggesting that the oxo ligand plays a key role in proton exchange. These results provide a basis to optimize this new class of H2 -evolving catalysts.
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Affiliation(s)
- Jean-Philippe Porcher
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05 (France)
| | - Thibault Fogeron
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05 (France)
| | - Maria Gomez-Mingot
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05 (France)
| | - Etienne Derat
- Sorbonne Universités, UPMC Université Paris 6, Institut Parisien de Chimie Moléculaire, UMR 8232 CNRS, 4 place Jussieu, 75252 Paris Cedex 5 (France)
| | - Lise-Marie Chamoreau
- Sorbonne Universités, UPMC Université Paris 6, Institut Parisien de Chimie Moléculaire, UMR 8232 CNRS, 4 place Jussieu, 75252 Paris Cedex 5 (France)
| | - Yun Li
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05 (France).
| | - Marc Fontecave
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05 (France).
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15
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Porcher J, Fogeron T, Gomez‐Mingot M, Derat E, Chamoreau L, Li Y, Fontecave M. A Bioinspired Molybdenum Complex as a Catalyst for the Photo‐ and Electroreduction of Protons. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201505607] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Jean‐Philippe Porcher
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05 (France)
| | - Thibault Fogeron
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05 (France)
| | - Maria Gomez‐Mingot
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05 (France)
| | - Etienne Derat
- Sorbonne Universités, UPMC Université Paris 6, Institut Parisien de Chimie Moléculaire, UMR 8232 CNRS, 4 place Jussieu, 75252 Paris Cedex 5 (France)
| | - Lise‐Marie Chamoreau
- Sorbonne Universités, UPMC Université Paris 6, Institut Parisien de Chimie Moléculaire, UMR 8232 CNRS, 4 place Jussieu, 75252 Paris Cedex 5 (France)
| | - Yun Li
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05 (France)
| | - Marc Fontecave
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Université Paris 6, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05 (France)
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16
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Majumdar A. Structural and functional models in molybdenum and tungsten bioinorganic chemistry: description of selected model complexes, present scenario and possible future scopes. Dalton Trans 2015; 43:8990-9003. [PMID: 24798698 DOI: 10.1039/c4dt00631c] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A brief description about some selected model complexes in molybdenum and tungsten bioinorganic chemistry is provided. The synthetic strategies involved and their limitations are discussed. Current status of molybdenum and tungsten bioinorganic modeling chemistry is presented briefly and synthetic problems associated therein are analyzed. Possible future directions which may expand the scope of modeling chemistry are suggested.
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Affiliation(s)
- Amit Majumdar
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India.
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Döring A, Fischer C, Schulzke C. Mono-oxo-bis-dithioveratrol-molybdate - in Solution a Model for Arsenite Oxidase and in the Solid State a Coordination Polymer with Unprecedented Binding Motifs. Z Anorg Allg Chem 2013. [DOI: 10.1002/zaac.201300076] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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18
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Bose M, Moula G, Sarkar S. Mono(maleonitriledithiolene)molybdenum(IV) and Bis(μ-sulfido)-Bridged Dimolybdenum(V) Complexes with MoS Moiety. Chem Biodivers 2012; 9:1867-79. [DOI: 10.1002/cbdv.201100450] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Moumita Bose
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
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19
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Seo J, Kim E. O-Atom Exchange between H2O and CO2 Mediated by a Bis(dithiolene)tungsten Complex. Inorg Chem 2012; 51:7951-3. [DOI: 10.1021/ic300906j] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Junhyeok Seo
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United
States
| | - Eunsuk Kim
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United
States
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20
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Yan Y, Chandrasekaran P, Mague JT, DeBeer S, Sproules S, Donahue JP. Redox-Controlled Interconversion between Trigonal Prismatic and Octahedral Geometries in a Monodithiolene Tetracarbonyl Complex of Tungsten. Inorg Chem 2011; 51:346-61. [DOI: 10.1021/ic201748v] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yong Yan
- Department of Chemistry, Tulane University, 6400 Freret Street, New Orleans,
Louisiana 70118-5698, United States
| | - Perumalreddy Chandrasekaran
- Department of Chemistry, Tulane University, 6400 Freret Street, New Orleans,
Louisiana 70118-5698, United States
- Department of Chemistry and
Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Joel T. Mague
- Department of Chemistry, Tulane University, 6400 Freret Street, New Orleans,
Louisiana 70118-5698, United States
| | - Serena DeBeer
- Department of Chemistry and
Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36,
D-45470 Mülheim an der Ruhr, Germany
| | - Stephen Sproules
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36,
D-45470 Mülheim an der Ruhr, Germany
- EPSRC National UK EPR Facility
and Service, Photon Science Institute, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - James P. Donahue
- Department of Chemistry, Tulane University, 6400 Freret Street, New Orleans,
Louisiana 70118-5698, United States
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Majumdar A, Holm RH. Specific incorporation of chalcogenide bridge atoms in molybdenum/tungsten-iron-sulfur single cubane clusters. Inorg Chem 2011; 50:11242-51. [PMID: 21985054 PMCID: PMC3215104 DOI: 10.1021/ic2018117] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An extensive series of heterometal-iron-sulfur single cubane-type clusters with core oxidation levels [MFe(3)S(3)Q](3+,2+) (M = Mo, W; Q = S, Se) has been prepared by means of a new method of cluster self-assembly. The procedure utilizes the assembly system [((t)Bu(3)tach)M(VI)S(3)]/FeCl(2)/Na(2)Q/NaSR in acetonitrile/THF and affords product clusters in 30-50% yield. The trisulfido precursor acts as a template, binding Fe(II) under reducing conditions and supplying the MS(3) unit of the product. The system leads to specific incorporation of a μ(3)-chalcogenide from an external source (Na(2)Q) and affords the products [((t)Bu(3)tach)MFe(3)S(3)QL(3)](0/1-) (L = Cl(-), RS(-)), among which are the first MFe(3)S(3)Se clusters prepared. Some 16 clusters have been prepared, 13 of which have been characterized by X-ray structure determinations including the incomplete cubane [((t)Bu(3)tach)MoFe(2)S(3)Cl(2)(μ(2)-SPh)], a possible trapped intermediate in the assembly process. Comparisons of structural and electronic features of clusters differing only in atom Q at one cubane vertex are provided. In comparative pairs of complexes differing only in Q, placement of one selenide atom in the core increases core volumes by about 2% over the Q = S case, sets the order Q = Se > S in Fe-Q bond lengths and Q = S > Se in Fe-Q-Fe bond angles, causes small positive shifts in redox potentials, and has an essentially nil effect on (57)Fe isomer shifts. Iron mean oxidation states and charge distributions are assigned to most clusters from isomer shifts. ((t)Bu(3)tach = 1,3,5-tert-butyl-1,3,5-triazacyclohexane).
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Affiliation(s)
- Amit Majumdar
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - R. H. Holm
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
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22
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Xi B, Holm RH. The [MoFe3S4]2+ oxidation state: synthesis, substitution reactions, and structures of phosphine-ligated cubane-type clusters with the S=2 ground state. Inorg Chem 2011; 50:6280-8. [PMID: 21648449 DOI: 10.1021/ic200641k] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The cluster [(Tp)MoFe(3)S(4)(PEt(3))(3)](1+) containing the cubane-type [MoFe(3)(μ(3)-S)(4)](2+) reduced core undergoes facile ligand substitution reactions at the iron sites leading to an extensive set of mono- and disubstituted species [(Tp)MoFe(3)S(4)(PEt(3))(3-n)L(n)](1-n) with L = halide, N(3)(-), PhS(-), PhSe(-), R(3)SiO(-), and R(3)SiS(-) and n = 1 and 2. Structures of 10 members of the set are reported. For two representative clusters, Curie behavior at 2-20 K indicates a spin-quintet ground state. Zero-field Mössbauer spectra consist of two doublets in a 2:1 intensity ratio. (57)Fe isomer shifts are consistent with the mean oxidation state Fe(3)(2.33+) arising from electron delocalization of the mixed-valence oxidation state description [Mo(3+)Fe(3+)Fe(2+)(2)]. Reaction of [(Tp)MoFe(3)S(4)(PEt(3))(2)Cl] with (Me(3)Si)(2)S affords [(Tp)MoFe(3)S(4)(PEt(3))(2)(SSiMe(3))], a likely first intermediate in the formation of the tricluster compound {[(Tp)MoFe(3)S(4)(PEt)(2)](3)S}(BPh(4)) from the reaction of [(Tp)MoFe(3)S(4)(PEt(3))(3)](BPh(4)) and NaSSiMe(3) in tetrahydrofuran (THF). The tricluster consists of three cluster units bound to a central μ(3)-S atom in a species of overall C(3) symmetry. Relatively few clusters in the [MoFe(3)S(4)](2+) oxidation state have been prepared compared to the abundance of clusters in the oxidized [MoFe(3)S(4)](3+) state. This work is the first comprehensive study of the [MoFe(3)S(4)](2+) state, one conspicuous feature of which is its ability to bind hard and soft σ-donors and strong to weak π-acid ligands. (Tp = tris(pyrazolyl)hydroborate(1-)).
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Affiliation(s)
- Bin Xi
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
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23
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Holm RH, Solomon EI, Majumdar A, Tenderholt A. Comparative molecular chemistry of molybdenum and tungsten and its relation to hydroxylase and oxotransferase enzymes. Coord Chem Rev 2011. [DOI: 10.1016/j.ccr.2010.10.017] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Yang L, Tehranchi J, Tolman WB. Reactions of Ph3Sb═S with copper(I) complexes supported by N-donor ligands: formation of stable adducts and S-transfer reactivity. Inorg Chem 2011; 50:2606-12. [PMID: 21338053 DOI: 10.1021/ic102449m] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In the exploration of sulfur-delivery reagents useful for synthesizing models of the tetracopper-sulfide cluster of nitrous oxide reductase, reactions of Ph(3)Sb═S with Cu(I) complexes of N,N,N',N'-tetramethyl-2R,3R-cyclohexanediamine (TMCHD) and 1,4,7-trialkyltriazacyclononanes (R(3)tacn; R = Me, Et, iPr) were studied. Treatment of [(R(3)tacn)Cu(NCCH(3))]SbF(6) (R = Me, Et, or iPr) with 1 equiv of S═SbPh(3) in CH(2)Cl(2) yielded adducts [(R(3)tacn)Cu(S═SbPh(3))]SbF(6) (1-3), which were fully characterized, including by X-ray crystallography. The adducts slowly decayed to [(R(3)tacn)(2)Cu(2)(μ-η(2):η(2)-S(2))](2+) species (4-6) and SbPh(3), or more quickly in the presence of additional [(R(3)tacn)Cu(NCCH(3))]SbF(6) to 4-6 and [(R(3)tacn)Cu(SbPh(3))]SbF(6) (7-9). The results of mechanistic studies of the latter process were consistent with rapid intermolecular exchange of S═SbPh(3) between 1-3 and added [(R(3)tacn)Cu(NCCH(3))]SbF(6), followed by conversion to product via a dicopper intermediate formed in a rapid pre-equilibrium step. Key evidence supporting this step came from the observation of saturation behavior in a plot of the initial rate of loss of 1 versus the initial concentration of [(Me(3)tacn)Cu(NCCH(3))]SbF(6). Also, treatment of [(TMCHD)Cu(CH(3)CN)]PF(6) with S═SbPh(3) led to the known tricopper cluster [(TMCHD)(3)Cu(3)(μ(3)-S)(2)](PF(6))(3) in good yield (79%), a synthetic procedure superior to that previously reported (Brown, E. C.; York, J. T.; Antholine, W. E.; Ruiz, E.; Alvarez, S.; Tolman, W. B. J. Am. Chem. Soc. 2005, 127, 13752-13753).
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Affiliation(s)
- Lei Yang
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
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25
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Sugimoto H, Tano H, Suyama K, Kobayashi T, Miyake H, Itoh S, Mtei RP, Kirk ML. Chalcogenidobis(ene-1,2-dithiolate)molybdenum(IV) complexes (chalcogenide E = O, S, Se): probing Mo≡E and ene-1,2-dithiolate substituent effects on geometric and electronic structure. Dalton Trans 2011; 40:1119-31. [PMID: 21165484 PMCID: PMC3168557 DOI: 10.1039/c0dt00871k] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
New square-pyramidal bis(ene-1,2-dithiolate)MoSe complexes, [Mo(IV)Se(L)(2)](2-), have been synthesised along with their terminal sulfido analogues, [Mo(IV)S(L)(2)](2-), using alkyl (L(C(4)H(8))), phenyl (L(Ph)) and methyl carboxylate (L(COOMe)) substituted dithiolene ligands (L). These complexes now complete three sets of Mo(IV)O, Mo(IV)S and Mo(IV)Se species that are coordinated with identical ene-1,2-dithiolate ligands. The [alkyl substituted Mo(S/Se)(L(C(4)H(8)))(2)](2-) complexes were reported in prior investigations (H. Sugimoto, T. Sakurai, H. Miyake, K. Tanaka and H. Tsukube, Inorg. Chem. 2005, 44, 6927, H. Tano, R. Tajima, H. Miyake, S. Itoh and H. Sugimoto, Inorg. Chem. 2008, 47, 7465). The new series of complexes enable a systematic investigation of terminal chalcogenido and supporting ene-1,2-dithiolate ligand effects on geometric structure, electronic structure, and spectroscopic properties. X-ray crystallographic analysis of these (Et(4)N)(2)[MoEL(2)] (E = terminal chalocogenide) complexes reveals an isostructural Mo centre that adopts a distorted square pyramidal geometry. The M≡E bond distances observed in the crystal structures and the ν(M≡E) vibrational frequencies indicate that these bonds are weakened with an increase in L→Mo electron donation (L(COOMe) < L(Ph) < L(C(4)H(8))), and this order is confirmed by an electrochemical study of the complexes. The (77)Se NMR resonances in MoSeL complexes appear at lower magnetic fields as the selenido ion became less basic from MoSeL(C(4)H(8)), MoSeL(Ph) and MoSeL(COOMe). Electronic absorption and resonance Raman spectroscopies have been used to assign key ligand-field, MLCT, LMCT and intraligand CT bands in complexes that possess the L(COOMe) ligand. The presence of low-energy intraligand CT transition in these MoEL(COOMe) compounds directly probes the electron withdrawing nature of the -COOMe substituents, and this underscores the complex electronic structure of square pyramidal bis(ene-1,2-dithiolate)-Mo(IV) complexes that possess extended dithiolene conjugation.
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Affiliation(s)
- Hideki Sugimoto
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871Japan
| | - Hiroyuki Tano
- Department of Chemistry, Graduate School of Science, Osaka City University, 3-3-138 Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Koichiro Suyama
- Department of Chemistry, Graduate School of Science, Osaka City University, 3-3-138 Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Tomoya Kobayashi
- Department of Chemistry, Graduate School of Science, Osaka City University, 3-3-138 Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Hiroyuki Miyake
- Department of Chemistry, Graduate School of Science, Osaka City University, 3-3-138 Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Shinobu Itoh
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871Japan
| | - Regina P. Mtei
- Department of Chemistry and Chemical Biology, The University of New Mexico, MSC03 2060, 1 University of New Mexico, Albuquerque, New Mexico 87131–0001, USA
| | - Martin L. Kirk
- Department of Chemistry and Chemical Biology, The University of New Mexico, MSC03 2060, 1 University of New Mexico, Albuquerque, New Mexico 87131–0001, USA
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26
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Deng L, Majumdar A, Lo W, Holm RH. Stabilization of 3:1 site-differentiated cubane-type clusters in the [Fe(4)S(4)](1+) core oxidation state by tertiary phosphine ligation: synthesis, core structural diversity, and S = 1/2 ground states. Inorg Chem 2010; 49:11118-26. [PMID: 21038882 DOI: 10.1021/ic101702b] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An extensive series of 3:1 site-differentiated cubane-type clusters [Fe(4)S(4)(PPr(i)(3))(3)L] (L = Cl(-), Br(-), I(-), RO(-), RS(-), RSe(-)) has been prepared in 40-80% yield by two methods: ligand substitution of [Fe(4)S(4)(PPr(i)(3))(4)](1+) in tetrahydrofuran (THF)/acetonitrile by reaction with monoanions, and reductive cleavage of ligand substrates (RSSR, RSeSeR, I(2)) by the all-ferrous clusters [Fe(8)S(8)(PPr(i)(3))(6)]/[Fe(16)S(16)(PPr(i)(3))(8)] in THF. These neutral clusters are stable and do not undergo ligand redistribution reactions involving charged species in benzene and THF solutions. X-ray structural studies confirm the cubane stereochemistry but with substantial and variable distortions of the [Fe(4)S(4)](1+) core from idealized cubic core geometry. Based on Fe-S bond lengths, seven clusters were found to have compressed tetragonal distortions (4 short and 8 long bonds), and the remaining seven display other types of distortions with different combinations of long, short, and intermediate bond lengths. These results further emphasize the facile deformabililty of this core oxidation state previously observed in [Fe(4)S(4)(SR)(4)](3-) clusters. The Fe(2.25+) mean oxidation state was demonstrated from (57)Fe isomer shifts, and the appearance of two quadrupole doublets arises from the spin-coupled |9/2,4,1/2> state. The S = 1/2 ground state was further supported by electron paramagnetic resonance spectra and magnetic susceptibility data.
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Affiliation(s)
- Liang Deng
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
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27
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Nguyen N, Harrison DJ, Lough AJ, De Crisci AG, Fekl U. Molybdenum Dithiolene Complexes as Structural Models for the Active Sites of Molybdenum(IV) Sulfide Hydrodesulfurization Catalysts. Eur J Inorg Chem 2010. [DOI: 10.1002/ejic.201000269] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Groysman S, Majumdar A, Zheng SL, Holm RH. Reactions of Monodithiolene Tungsten(VI) Sulfido Complexes with Copper(I) in Relation to the Structure of the Active Site of Carbon Monoxide Dehydrogenase. Inorg Chem 2009; 49:1082-9. [DOI: 10.1021/ic902066m] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Stanislav Groysman
- Department of Chemisty and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138
| | - Amit Majumdar
- Department of Chemisty and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138
| | - Shao-Liang Zheng
- Department of Chemisty and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138
| | - R. H. Holm
- Department of Chemisty and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138
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29
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Sugimoto H, Tano H, Toyota K, Tajima R, Miyake H, Takahashi I, Hirota S, Itoh S. Reduction of Bis(dithiolene)oxo(disulfido)tungsten(VI) Complex with Dihydrogen Related to the Chemical Function of the Fourth Tungsten-Containing Enzyme (WOR4) from Pyrococcus furiosus. J Am Chem Soc 2009; 132:8-9. [DOI: 10.1021/ja907164s] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hideki Sugimoto
- Department of Material and Life Science, Division of Advanced Science and Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan, Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan, Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Hiroyuki Tano
- Department of Material and Life Science, Division of Advanced Science and Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan, Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan, Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Kazuo Toyota
- Department of Material and Life Science, Division of Advanced Science and Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan, Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan, Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Reiko Tajima
- Department of Material and Life Science, Division of Advanced Science and Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan, Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan, Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Hiroyuki Miyake
- Department of Material and Life Science, Division of Advanced Science and Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan, Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan, Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Isao Takahashi
- Department of Material and Life Science, Division of Advanced Science and Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan, Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan, Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Shun Hirota
- Department of Material and Life Science, Division of Advanced Science and Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan, Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan, Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Shinobu Itoh
- Department of Material and Life Science, Division of Advanced Science and Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan, Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan, Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
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Ryde U, Schulzke C, Starke K. Which functional groups of the molybdopterin ligand should be considered when modeling the active sites of the molybdenum and tungsten cofactors? A density functional theory study. J Biol Inorg Chem 2009; 14:1053-64. [PMID: 19479286 PMCID: PMC3085732 DOI: 10.1007/s00775-009-0548-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Accepted: 05/01/2009] [Indexed: 11/29/2022]
Abstract
A density functional theory study of the influence of the various functional groups of the molybdopterin ligand on electronic and geometric properties of active-site models for the molybdenum and tungsten cofactors has been undertaken. We used analogous molybdenum and tungsten complexes with increasingly accurate representation of the molybdopterin ligands and compared bond lengths, angles, charge distribution, composition of the binding orbitals, as well as the redox potentials in relation to each other. On the basis of our findings, we suggest using ligand systems including the pyrane and the pyrazine rings, besides the dithiolene function, to obtain sufficiently reliable computational, but also synthetic, models for the molybdenum and tungsten cofactors, whereas the second ring of the pterin might be neglected for efficiency reasons.
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Affiliation(s)
- Ulf Ryde
- Department of Theoretical Chemistry, Chemical Center, Lund University, 124, 221 00 Lund, Sweden
| | - Carola Schulzke
- Institut für Anorganische Chemie, Georg-August-Universität Göttingen, Tammannstr. 4, 37077 Göttingen, Germany
| | - Kerstin Starke
- Institut für Anorganische Chemie, Georg-August-Universität Göttingen, Tammannstr. 4, 37077 Göttingen, Germany
- Department of Chemical Physics, Chemical Center, Lund University, 124, 221 00 Lund, Sweden
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Ribera A, Pérez-Pla F, Llopis E, Cervilla A, Domenech A. A kinetic model for the oxidation of benzenethiol catalyzed by the [MoVIO2(O2CC(S)(C6H5)2)2]2− complex intercalated in a Zn(II)–Al(III) layered double hydroxide host. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.molcata.2009.02.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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32
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Groysman S, Holm RH. A series of mononuclear quasi-two-coordinate copper(I) complexes employing a sterically demanding thiolate ligand. Inorg Chem 2009; 48:621-7. [PMID: 19138143 DOI: 10.1021/ic801836k] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A series of two-coordinate thiolate complexes [Cu(SAr*)L] was synthesized as possible reactants in forming analogues of the active site of Mo/Cu-containing carbon monoxide dehydrogenase. Complexes with L = PPh(3) (1), 2,6-lutidine (2), and the N-heterocyclic carbene Pr(i)(2)NHCMe(2) (3) have been prepared by the reaction of [CuCl(PPh(3))(3)] (1) or [CuBr(SMe(2))] (2, 3) with ligand L and the exceptionally sterically encumbered ligand Ar*S = 2,6-bis(2,4,6-triisopropylphenyl)benzenethiolate(1-). The reaction of [CuBr(SMe(2))] with the thiolate in the absence of added L afforded trinuclear [Cu(3)(SAr*)(2)Br] (7). The carbene complex (3) undergoes Cu-C bond insertion with sulfur to form the thiourea complex [Cu(SAr*)(Pr(i)(2)Me(2)ImS)] (4). The complexes [Cu(Ar*)L] with L = tetrahydrothiophene (5) and 2,6-lutidine (6) were obtained by reaction of Ar*Li(OEt(2)) with CuBr/L. These species did not undergo clean Cu-C bond insertion with sulfur transfer agents; the disulfide Ar*SSCH(2)Ph (9) was isolated from the reaction of 6 with (PhCH(2)S)(2)S. The structures of all complexes and 9 were determined. Whereas 5 and 6 are strictly two-coordinate with linear C-Cu-L angles, 1-4 are quasi-two-coordinate because of weak 3d-C(ppi) interactions with a phenyl group, leading to nonlinear structures (S-Cu-L = 135-164 degrees).
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Affiliation(s)
- Stanislav Groysman
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
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Sugimoto H, Suyama K, Sugimoto K, Miyake H, Takahashi I, Hirota S, Itoh S. A New Class of Sulfido/Oxo(dithiolene)−Molybdenum(IV) Complexes Derived from Sulfido/Oxo-Bis(tetrasulfido)molybdenum(IV) Anions. Inorg Chem 2008; 47:10150-7. [DOI: 10.1021/ic800832a] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hideki Sugimoto
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan, Rigaku Corporation, Akishima, Tokyo 196-8666, Japan, and Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, 630-0192 Japan
| | - Koichiro Suyama
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan, Rigaku Corporation, Akishima, Tokyo 196-8666, Japan, and Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, 630-0192 Japan
| | - Kunihisa Sugimoto
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan, Rigaku Corporation, Akishima, Tokyo 196-8666, Japan, and Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, 630-0192 Japan
| | - Hiroyuki Miyake
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan, Rigaku Corporation, Akishima, Tokyo 196-8666, Japan, and Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, 630-0192 Japan
| | - Isao Takahashi
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan, Rigaku Corporation, Akishima, Tokyo 196-8666, Japan, and Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, 630-0192 Japan
| | - Shun Hirota
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan, Rigaku Corporation, Akishima, Tokyo 196-8666, Japan, and Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, 630-0192 Japan
| | - Shinobu Itoh
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan, Rigaku Corporation, Akishima, Tokyo 196-8666, Japan, and Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, 630-0192 Japan
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Sugimoto H, Tsukube H. Chemical analogues relevant to molybdenum and tungsten enzyme reaction centres toward structural dynamics and reaction diversity. Chem Soc Rev 2008; 37:2609-19. [PMID: 19020675 DOI: 10.1039/b610235m] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Recent characterisation of molybdenum and tungsten enzymes revealed novel structural types of reaction centres, as well as providing new subjects of interest as synthetic chemical analogues. This tutorial review highlights the structure/reactivity relationships of the enzyme reaction centres and chemical analogues. Chemical analogues for the oxygen atom transfer enzymes have been well expanded in structure and reactivity. Other types of chemical analogues that exhibit different coordination chemistry have recently been presented for reaction centres of the hydroxylation and dehydrogenation enzymes and others.
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Affiliation(s)
- Hideki Sugimoto
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka, 558-8585, Japan.
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Groysman S, Wang JJ, Tagore R, Lee SC, Holm RH. A Biomimetic Approach to Oxidized Sites in the Xanthine Oxidoreductase Family: Synthesis and Stereochemistry of Tungsten(VI) Analogue Complexes. J Am Chem Soc 2008; 130:12794-807. [DOI: 10.1021/ja804000k] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Stanislav Groysman
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, and Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
| | - Jun-Jieh Wang
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, and Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
| | - Ranitendranath Tagore
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, and Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
| | - Sonny C. Lee
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, and Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
| | - R. H. Holm
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, and Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
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Tano H, Tajima R, Miyake H, Itoh S, Sugimoto H. Selenidobis(dithiolene)metal(IV) Complexes (Metal M = Mo, W) Potentially Related to the Nicotinic Acid Hydroxylase Reaction Center: Redox Aspects in Electrochemistry and Oxygen Atom Transfer from Me3NO to MIV Centers. Inorg Chem 2008; 47:7465-7. [DOI: 10.1021/ic8009942] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hiroyuki Tano
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Reiko Tajima
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Hiroyuki Miyake
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Shinobu Itoh
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Hideki Sugimoto
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
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Reversible interconversion of carbon dioxide and formate by an electroactive enzyme. Proc Natl Acad Sci U S A 2008; 105:10654-8. [PMID: 18667702 DOI: 10.1073/pnas.0801290105] [Citation(s) in RCA: 303] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Carbon dioxide (CO(2)) is a kinetically and thermodynamically stable molecule. It is easily formed by the oxidation of organic molecules, during combustion or respiration, but is difficult to reduce. The production of reduced carbon compounds from CO(2) is an attractive proposition, because carbon-neutral energy sources could be used to generate fuel resources and sequester CO(2) from the atmosphere. However, available methods for the electrochemical reduction of CO(2) require excessive overpotentials (are energetically wasteful) and produce mixtures of products. Here, we show that a tungsten-containing formate dehydrogenase enzyme (FDH1) adsorbed to an electrode surface catalyzes the efficient electrochemical reduction of CO(2) to formate. Electrocatalysis by FDH1 is thermodynamically reversible--only small overpotentials are required, and the point of zero net catalytic current defines the reduction potential. It occurs under thoroughly mild conditions, and formate is the only product. Both as a homogeneous catalyst and on the electrode, FDH1 catalyzes CO(2) reduction with a rate more than two orders of magnitude faster than that of any known catalyst for the same reaction. Formate oxidation is more than five times faster than CO(2) reduction. Thermodynamically, formate and hydrogen are oxidized at similar potentials, so formate is a viable energy source in its own right as well as an industrially important feedstock and a stable intermediate in the conversion of CO(2) to methanol and methane. FDH1 demonstrates the feasibility of interconverting CO(2) and formate electrochemically, and it is a template for the development of robust synthetic catalysts suitable for practical applications.
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Kuiper DS, Douthwaite RE, Mayol AR, Wolczanski PT, Lobkovsky EB, Cundari TR, Lam OP, Meyer K. Molybdenum and tungsten structural differences are dependent on ndz(2)/(n + 1)s mixing: comparisons of (silox)3MX/R (M = Mo, W; silox = (t)Bu3SiO). Inorg Chem 2008; 47:7139-53. [PMID: 18624403 DOI: 10.1021/ic800139c] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Treatment of trans-(Et 2O) 2MoCl 4 with 2 or 3 equiv of Na(silox) (i.e., NaOSi (t) Bu 3) afforded (silox) 3MoCl 2 ( 1-Mo) or (silox) 3MoCl ( 2-Mo). Purification of 2-Mo was accomplished via addition of PMe 3 to precipitate (silox) 3ClMoPMe 3 ( 2-MoPMe 3), followed by thermolysis to remove phosphine. Use of MoCl 3(THF) 3 with various amounts of Na(silox) produced (silox) 2ClMoMoCl(silox) 2 ( 3-Mo). Alkylation of 2-Mo with MeMgBr or EtMgBr afforded (silox) 3MoR (R = Me, 2-MoMe; Et, 2-MoEt). 2-MoEt was also synthesized from C 2H 4 and (silox) 3MoH, which was prepared from 2-Mo and NaBEt 3H. Thermolysis of WCl 6 with HOSi ( t )Bu 3 afforded (silox) 2WCl 4 ( 4-W), and sequential treatment of 4-W with Na/Hg and Na(silox) provided (silox) 3WCl 2 ( 1-W, tbp, X-ray), which was alternatively prepared from trans-(Et 2S) 2WCl 4 and 3 equiv of Tl(silox). Na/Hg reduction of 1-W generated (silox) 3WCl ( 2-W). Alkylation of 2-W with MeMgBr produced (silox) 3WMe ( 2-WMe), which dehydrogenated to (silox) 3WCH ( 6-W) with Delta H (double dagger) = 14.9(9) kcal/mol and Delta S (double dagger) = -26(2) eu. Magnetism and structural studies revealed that 2-Mo and 2-MoEt have triplet ground states (GS) and distorted trigonal monopyramid (tmp) and tmp structures, respectively. In contrast, 2-W and 2-WMe possess squashed-T d (distorted square planar) structures, and the former has a singlet GS. Quantum mechanics/molecular mechanics studies of the S = 0 and S = 1 states for full models of 2-Mo, 2-MoEt, 2-W, and 2-WMe corroborate the experimental findings and are consistent with the greater nd z (2) /( n + 1)s mixing in the third-row transition-metal species being the dominant feature in determining the structural disparity between molybdenum and tungsten.
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Affiliation(s)
- David S Kuiper
- Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, USA
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Najmudin S, González PJ, Trincão J, Coelho C, Mukhopadhyay A, Cerqueira NMFSA, Romão CC, Moura I, Moura JJG, Brondino CD, Romão MJ. Periplasmic nitrate reductase revisited: a sulfur atom completes the sixth coordination of the catalytic molybdenum. J Biol Inorg Chem 2008; 13:737-53. [PMID: 18327621 DOI: 10.1007/s00775-008-0359-6] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2007] [Accepted: 02/21/2008] [Indexed: 11/30/2022]
Abstract
Nitrate reductase from Desulfovibrio desulfuricans ATCC 27774 (DdNapA) is a monomeric protein of 80 kDa harboring a bis(molybdopterin guanine dinucleotide) active site and a [4Fe-4S] cluster. Previous electron paramagnetic resonance (EPR) studies in both catalytic and inhibiting conditions showed that the molybdenum center has high coordination flexibility when reacted with reducing agents, substrates or inhibitors. As-prepared DdNapA samples, as well as those reacted with substrates and inhibitors, were crystallized and the corresponding structures were solved at resolutions ranging from 1.99 to 2.45 A. The good quality of the diffraction data allowed us to perform a detailed structural study of the active site and, on that basis, the sixth molybdenum ligand, originally proposed to be an OH/OH(2) ligand, was assigned as a sulfur atom after refinement and analysis of the B factors of all the structures. This unexpected result was confirmed by a single-wavelength anomalous diffraction experiment below the iron edge (lambda = 1.77 A) of the as-purified enzyme. Furthermore, for six of the seven datasets, the S-S distance between the sulfur ligand and the Sgamma atom of the molybdenum ligand Cys(A140) was substantially shorter than the van der Waals contact distance and varies between 2.2 and 2.85 A, indicating a partial disulfide bond. Preliminary EPR studies under catalytic conditions showed an EPR signal designated as a turnover signal (g values 1.999, 1.990, 1.982) showing hyperfine structure originating from a nucleus of unknown nature. Spectropotentiometric studies show that reduced methyl viologen, the electron donor used in the catalytic reaction, does not interact directly with the redox cofactors. The turnover signal can be obtained only in the presence of the reaction substrates. With use of the optimized conditions determined by spectropotentiometric titration, the turnover signal was developed with (15)N-labeled nitrate and in D(2)O-exchanged DdNapA samples. These studies indicate that this signal is not associated with a Mo(V)-nitrate adduct and that the hyperfine structure originates from two equivalent solvent-exchangeable protons. The new coordination sphere of molybdenum proposed on the basis of our studies led us to revise the currently accepted reaction mechanism for periplasmic nitrate reductases. Proposals for a new mechanism are discussed taking into account a molybdenum and ligand-based redox chemistry, rather than the currently accepted redox chemistry based solely on the molybdenum atom.
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Affiliation(s)
- Shabir Najmudin
- Departamento de Química, FCT-UNL, REQUIMTE/CQFB, Monte de Caparica, 2829-516, Almada, Portugal.
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Sugimoto H, Sugimoto K. New bis(pyranodithiolene) tungsten(IV) and (VI) complexes as chemical analogues of the active sites of tungsten enzymes. INORG CHEM COMMUN 2008. [DOI: 10.1016/j.inoche.2007.10.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Sugimoto H, Tano H, Tajima R, Miyake H, Tsukube H, Ohi H, Itoh S. In Situ Generation of Oxo−sulfidobis(dithiolene)tungsten(VI) Complexes: Active-Site Models for the Aldehyde Ferredoxin Oxidoreductase Family of Tungsten Enzymes. Inorg Chem 2007; 46:8460-2. [PMID: 17854180 DOI: 10.1021/ic7012733] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Oxo-sulfidobis(dithiolene)tungsten(VI) complexes were prepared in situ by the reaction of oxobis(dithiolene)tungsten(V) precursors with hydrosulfide (SH-). The complexes, characterized by UV-vis, electrospray ionization mass spectrometry, IR, and resonance Raman spectroscopies, model the proposed coordination environment and observed hydrolytic reactions of members of the aldehyde ferredoxin oxidoreductase family of tungsten enzymes.
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Affiliation(s)
- Hideki Sugimoto
- Department of Chemistry, Graduate School of Science, Osaka City University, Osaka 558-8585, Japan.
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Wang JJ, Groysman S, Lee SC, Holm RH. Synthesis of Structural Analogues of the Oxidized Sites in the Xanthine Oxidoreductase Enzyme Family. J Am Chem Soc 2007; 129:7512-3. [PMID: 17530853 DOI: 10.1021/ja0724442] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jun-Jieh Wang
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
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