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Canote CA, Kilyanek SM. Reactivity of metal dioxo complexes. Dalton Trans 2024; 53:4874-4889. [PMID: 38379444 DOI: 10.1039/d3dt04390h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2024]
Abstract
Metal dioxo chemistry and its diverse reactivity are presented with an emphasis on the mechanisms of reactivity. Work from approximately the last decade is surveyed and organized by metal. In particular, the chemistry of cis-dioxo metal complexes is discussed at length. Reactions are grouped by generic type, including addition across a metal oxo bond, oxygen atom transfer, and radical atom transfer reactions. Attention is given to advances in deoxygenation chemistry, oxidation chemistry, and reductive transformations.
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Affiliation(s)
- Cody A Canote
- Department of Chemistry and Biochemistry, 1 University of Arkansas, Fayetteville, AR 72701, USA.
| | - Stefan M Kilyanek
- Department of Chemistry and Biochemistry, 1 University of Arkansas, Fayetteville, AR 72701, USA.
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2
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Ćorović MZ, Belaj F, Mösch-Zanetti NC. Dioxygen Activation by a Bioinspired Tungsten(IV) Complex. Inorg Chem 2023; 62:5669-5676. [PMID: 36989414 PMCID: PMC10091480 DOI: 10.1021/acs.inorgchem.3c00228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
An increasing number of discovered tungstoenzymes raises interest in the biomimetic chemistry of tungsten complexes in oxidation states +IV, +V, and +VI. Bioinspired (sulfur-rich) tungsten(VI) dioxido complexes are relatively prevalent in literature. Still, their energetically demanding reduction directly correlates with a small number of known tungsten(IV) oxido complexes, whose chemistry is not well explored. In this paper, a reduction of the [WO2(6-MePyS)2] (6-MePyS = 6-methylpyridine-2-thiolate) complex with PMe3 to a phosphine-stabilized tungsten(IV) oxido complex [WO(6-MePyS)2(PMe3)2] is described. This tungsten(IV) complex partially releases one PMe3 ligand in solution, creating a vacant coordination site capable of activating dioxygen to form [WO2(6-MePyS)2] and OPMe3. Therefore, [WO2(6-MePyS)2] can be used as a catalyst for the aerobic oxidation of PMe3, rendering this complex a rare example of a tungsten system utilizing dioxygen in homogeneous catalysis. Additionally, the investigation of the reactivity of the tungsten(IV) oxido complex with acetylene, substrate of a tungstoenzyme acetylene hydratase (AH), revealed the formation of the tungsten(IV) acetylene adduct. Although this adduct was previously reported as an oxidation product of the tungsten(II) acetylene carbonyl complex, here it is obtained via substitution at the sulfur-rich tungsten(IV) center, mimicking the initial step of the first shell mechanism for AH as suggested by computational studies.
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Affiliation(s)
- Miljan Z Ćorović
- Institute of Chemistry, Inorganic Chemistry, University of Graz, 8010 Graz, Austria
| | - Ferdinand Belaj
- Institute of Chemistry, Inorganic Chemistry, University of Graz, 8010 Graz, Austria
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3
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Ćorović MZ, Wiedemaier F, Belaj F, Mösch-Zanetti NC. Replacement of Molybdenum by Tungsten in a Biomimetic Complex Leads to an Increase in Oxygen Atom Transfer Catalytic Activity. Inorg Chem 2022; 61:12415-12424. [PMID: 35894844 PMCID: PMC9367641 DOI: 10.1021/acs.inorgchem.2c01868] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Upon replacement of molybdenum by tungsten in DMSO reductase isolated from the Rhodobacteraceae family, the derived enzyme catalyzes DMSO reduction faster. To better understand this behavior, we synthesized two tungsten(VI) dioxido complexes [WVIO2L2] with pyridine- (PyS) and pyrimidine-2-thiolate (PymS) ligands, isostructural to analogous molybdenum complexes we reported recently. Higher oxygen atom transfer (OAT) catalytic activity was observed with [WO2(PyS)2] compared to the Mo species, independent of whether PMe3 or PPh3 was used as the oxygen acceptor. [WVIO2L2] complexes undergo reduction with an excess of PMe3, yielding the tungsten(IV) oxido species [WOL2(PMe3)2], while with PPh3, no reactions are observed. Although OAT reactions from DMSO to phosphines are known for tungsten complexes, [WOL2(PMe3)2] are the first fully characterized phosphine-stabilized intermediates. By following the reaction of these reduced species with excess DMSO via UV-vis spectroscopy, we observed that tungsten compounds directly react to WVIO2 complexes while the Mo analogues first form μ-oxo Mo(V) dimers [Mo2O3L4]. Density functional theory calculations confirm that the oxygen atom abstraction from WVIO2 is an endergonic process contrasting the respective reaction with molybdenum. Here, we suggest that depending on the sacrificial oxygen acceptor, the tungsten complex may participate in catalysis either via a redox reaction or as an electrophile.
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Affiliation(s)
- Miljan Z Ćorović
- Institute of Chemistry, Inorganic Chemistry, University of Graz, 8010 Graz, Austria
| | - Fabian Wiedemaier
- Institute of Chemistry, Inorganic Chemistry, University of Graz, 8010 Graz, Austria
| | - Ferdinand Belaj
- Institute of Chemistry, Inorganic Chemistry, University of Graz, 8010 Graz, Austria
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4
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Dinda S, Pramanik S, Basu J, Patra SC, Pramanik K, Ganguly S. Azo-oximate metal-carbonyl to metallocarboxylic acid via the intermediate Ir(III) radical congener: quest for co-ligand driven stability of open- and closed-shell complexes. Dalton Trans 2022; 51:10121-10135. [PMID: 35731229 DOI: 10.1039/d2dt00345g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The redox non-innocent behavior of the diaryl-azo-oxime ligand LNOH1 has been accentuated via the synthesis of metastable anion radical complexes of type trans-[Ir(LNO˙-)Cl(CO)(PPh3)2] 2 (CO is trans to azo group of the ligand) by the oxidative coordination reaction of 1 with Vaska's complex. The stereochemical role of co-ligands vis-à-vis the interplay of π-bonding has been found to be decisive in controlling the aptitude of the coordinated redox non-innocent ligand to accept or reject an electron. This has been clarified via the isolation of quite a few complexes as well as the failure to synthesize some others. The oxidized analogues of type trans-[Ir(LNO-)Cl(CO)(PPh3)2]+2+ (CO and azo group of the ligand are trans) as well as its cis isomer cis-[Ir(LNO-)Cl(CO)(PPh3)2]+3+ (CO and azo group of the ligand are cis) have been structurally characterized but the radical anion congener of the latter could not be synthesized. Furthermore, the closed shell complexes [Ir(LNO-)Cl2(PPh3)2] 4 and [Ir(LNO-)2Cl(PPh3)] 5 have been well characterized by diffraction as well as spectral techniques but their corresponding azo anion radical complexes could not be isolated and this is attributed to the trans influence of ancillary ligands. The anion radical complexes trans-[Ir(LNO˙-)Cl(CO)(PPh3)2] 2 may be rapidly transformed to the metallocarboxylic acids trans-[Ir(LNO-)Cl(CO2H)(PPh3)2] 6via a proton-coupled electron transfer (PCET) process, thereby demonstrating the role of odd electron over the coordinated ligand framework to trigger metal-mediated carbonyl to carboxylic acid functionalization. Complexes 6 are further stabilized via intramolecular -CO2H⋯ON- (carboxylic acid⋯oximato) H-bonding. The optoelectronic properties as well as the origin of transitions in the complexes were analyzed by TD-DFT and theoretical analysis, which further disclose that the odd electron in trans-[Ir(LNO˙-)Cl(CO)(PPh3)2] 2 is primarily azo-oxime centric with very low contribution from the iridium center.
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Affiliation(s)
- Soumitra Dinda
- Department of Chemistry, St. Xavier's College (Autonomous), Kolkata - 700016, India.
| | - Shuvam Pramanik
- Department of Chemistry, Jadavpur University, Kolkata 700032, India
| | - Jaydeep Basu
- Department of Chemistry, St. Xavier's College (Autonomous), Kolkata - 700016, India.
| | | | | | - Sanjib Ganguly
- Department of Chemistry, St. Xavier's College (Autonomous), Kolkata - 700016, India.
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5
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Singh P, Srivastava R. Utilization of bio-inspired catalyst for CO2 reduction into green fuels: Recent advancement and future perspectives. J CO2 UTIL 2021. [DOI: 10.1016/j.jcou.2021.101748] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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6
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Vidovič C, Belaj F, Mösch‐Zanetti NC. Soft Scorpionate Hydridotris(2-mercapto-1-methylimidazolyl) borate) Tungsten-Oxido and -Sulfido Complexes as Acetylene Hydratase Models. Chemistry 2020; 26:12431-12444. [PMID: 32640122 PMCID: PMC7589279 DOI: 10.1002/chem.202001127] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 06/05/2020] [Indexed: 11/08/2022]
Abstract
A series of WIV alkyne complexes with the sulfur-rich ligand hydridotris(2-mercapto-1-methylimidazolyl) borate) (TmMe ) are presented as bio-inspired models to elucidate the mechanism of the tungstoenzyme acetylene hydratase (AH). The mono- and/or bis-alkyne precursors were reacted with NaTmMe and the resulting complexes [W(CO)(C2 R2 )(TmMe )Br] (R=H 1, Me 2) oxidized to the target [WE(C2 R2 )(TmMe )Br] (E=O, R=H 4, Me 5; E=S, R=H 6, Me 7) using pyridine-N-oxide and methylthiirane. Halide abstraction with TlOTf in MeCN gave the cationic complexes [WE(C2 R2 )(MeCN)(TmMe )](OTf) (E=CO, R=H 10, Me 11; E=O, R=H 12, Me 13; E=S, R=H 14, Me 15). Without MeCN, dinuclear complexes [W2 O(μ-O)(C2 Me2 )2 (TmMe )2 ](OTf)2 (8) and [W2 (μ-S)2 (C2 Me2 )(TmMe )2 ](OTf)2 (9) could be isolated showing distinct differences between the oxido and sulfido system with the latter exhibiting only one molecule of C2 Me2 . This provides evidence that a fine balance of the softness at W is important for acetylene coordination. Upon dissolving complex 8 in acetonitrile complex 13 is reconstituted in contrast to 9. All complexes exhibit the desired stability toward water and the observed effective coordination of the scorpionate ligand avoids decomposition to disulfide, an often-occurring reaction in sulfur ligand chemistry. Hence, the data presented here point toward a mechanism with a direct coordination of acetylene in the active site and provide the basis for further model chemistry for acetylene hydratase.
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Affiliation(s)
- Carina Vidovič
- University of GrazInstitute of ChemistryDepartment of Inorganic ChemistrySchuberstraße 18010GrazAustria
| | - Ferdinand Belaj
- University of GrazInstitute of ChemistryDepartment of Inorganic ChemistrySchuberstraße 18010GrazAustria
| | - Nadia C. Mösch‐Zanetti
- University of GrazInstitute of ChemistryDepartment of Inorganic ChemistrySchuberstraße 18010GrazAustria
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7
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Ehweiner MA, Wiedemaier F, Belaj F, Mösch-Zanetti NC. Oxygen Atom Transfer Reactivity of Molybdenum(VI) Complexes Employing Pyrimidine- and Pyridine-2-thiolate Ligands. Inorg Chem 2020; 59:14577-14593. [PMID: 32951421 DOI: 10.1021/acs.inorgchem.0c02412] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Four dioxidomolybdenum(VI) complexes of the general structure [MoO2L2] employing the S,N-bidentate ligands pyrimidine-2-thiolate (PymS, 1), pyridine-2-thiolate (PyS, 2), 4-methylpyridine-2-thiolate (4-MePyS, 3) and 6-methylpyridine-2-thiolate (6-MePyS, 4) were synthesized and characterized by spectroscopic means and single-crystal X-ray diffraction analysis (2-4). Complexes 1-4 were reacted with PPh3 and PMe3, respectively, to investigate their oxygen atom transfer (OAT) reactivity and catalytic applicability. Reduction with PPh3 leads to symmetric molybdenum(V) dimers of the general structure [Mo2O3L4] (6-9). Kinetic studies showed that the OAT from [MoO2L2] to PPh3 is 5 times faster for the PymS system than for the PyS and 4-MePyS systems. The reaction of complexes 1-3 with PMe3 gives stable molybdenum(IV) complexes of the structure [MoOL2(PMe3)2] (10-12), while reduction of [MoO2(6-MePyS)2] (4) yields [MoO(6-MePyS)2(PMe3)] (13) with only one PMe3 coordinated to the metal center. The activity of complexes 1-4 in catalytic OAT reactions involving Me2SO and Ph2SO as oxygen donors and PPh3 as an oxygen acceptor has been investigated to assess the influence of the varied ligand frameworks on the OAT reaction rates. It was found that [MoO2(PymS)2] (1) and [MoO2(6-MePyS)2] (4) are similarly efficient catalysts, while complexes 2 and 3 are only moderately active. In the catalytic oxidation of PMe3 with Me2SO, complex 4 is the only efficient catalyst. Complexes 1-4 were also found to catalytically reduce NO3- with PPh3, although their reactivity is inhibited by further reduced species such as NO, as exemplified by the formation of the nitrosyl complex [Mo(NO)(PymS)3] (14), which was identified by single-crystal X-ray diffraction analysis. Computed ΔG⧧ values for the very first step of the OAT were found to be lower for complexes 1 and 4 than for 2 and 3, explaining the difference in catalytic reactivity between the two pairs and revealing the requirement for an electron-deficient ligand system.
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Affiliation(s)
- Madeleine A Ehweiner
- Institute of Chemistry, Inorganic Chemistry, University of Graz, Schubertstrasse 1, 8010 Graz, Austria
| | - Fabian Wiedemaier
- Institute of Chemistry, Physical and Theoretical Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria
| | - Ferdinand Belaj
- Institute of Chemistry, Inorganic Chemistry, University of Graz, Schubertstrasse 1, 8010 Graz, Austria
| | - Nadia C Mösch-Zanetti
- Institute of Chemistry, Inorganic Chemistry, University of Graz, Schubertstrasse 1, 8010 Graz, Austria
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8
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Li Y, Go YK, Ooka H, He D, Jin F, Kim SH, Nakamura R. Enzyme Mimetic Active Intermediates for Nitrate Reduction in Neutral Aqueous Media. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202002647] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Yamei Li
- Biofunctional Catalyst Research TeamRIKEN Center for Sustainable Resource Science (CSRS) 2-1 Hirosawa Wako Saitama 351-0198 Japan
- Earth-Life Science Institute (ELSI)Tokyo Institute of Technology 2-12-1-IE-1 Ookayama, Meguro-ku Tokyo 152-8550 Japan
| | - Yoo Kyung Go
- Western Seoul CenterKorea Basic Science Institute (KBSI) Seoul 03759 Korea
| | - Hideshi Ooka
- Biofunctional Catalyst Research TeamRIKEN Center for Sustainable Resource Science (CSRS) 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Daoping He
- Biofunctional Catalyst Research TeamRIKEN Center for Sustainable Resource Science (CSRS) 2-1 Hirosawa Wako Saitama 351-0198 Japan
- School of Environmental Science and EngineeringState Key Lab of Metal Matrix CompositesShanghai Jiao Tong University 800 Dongchuan Road Shanghai 200240 P. R. China
| | - Fangming Jin
- School of Environmental Science and EngineeringState Key Lab of Metal Matrix CompositesShanghai Jiao Tong University 800 Dongchuan Road Shanghai 200240 P. R. China
| | - Sun Hee Kim
- Western Seoul CenterKorea Basic Science Institute (KBSI) Seoul 03759 Korea
| | - Ryuhei Nakamura
- Biofunctional Catalyst Research TeamRIKEN Center for Sustainable Resource Science (CSRS) 2-1 Hirosawa Wako Saitama 351-0198 Japan
- Earth-Life Science Institute (ELSI)Tokyo Institute of Technology 2-12-1-IE-1 Ookayama, Meguro-ku Tokyo 152-8550 Japan
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9
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Enzyme Mimetic Active Intermediates for Nitrate Reduction in Neutral Aqueous Media. Angew Chem Int Ed Engl 2020; 59:9744-9750. [DOI: 10.1002/anie.202002647] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Indexed: 11/07/2022]
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10
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Duffus BR, Schrapers P, Schuth N, Mebs S, Dau H, Leimkühler S, Haumann M. Anion Binding and Oxidative Modification at the Molybdenum Cofactor of Formate Dehydrogenase from Rhodobacter capsulatus Studied by X-ray Absorption Spectroscopy. Inorg Chem 2019; 59:214-225. [PMID: 31814403 DOI: 10.1021/acs.inorgchem.9b01613] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Formate dehydrogenase (FDH) enzymes are versatile catalysts for CO2 conversion. The FDH from Rhodobacter capsulatus contains a molybdenum cofactor with the dithiolene functions of two pyranopterin guanine dinucleotide molecules, a conserved cysteine, and a sulfido group bound at Mo(VI). In this study, we focused on metal oxidation state and coordination changes in response to exposure to O2, inhibitory anions, and redox agents using X-ray absorption spectroscopy (XAS) at the Mo K-edge. Differences in the oxidative modification of the bis-molybdopterin guanine dinucleotide (bis-MGD) cofactor relative to samples prepared aerobically without inhibitor, such as variations in the relative numbers of sulfido (Mo═S) and oxo (Mo═O) bonds, were observed in the presence of azide (N3-) or cyanate (OCN-). Azide provided best protection against O2, resulting in a quantitatively sulfurated cofactor with a displaced cysteine ligand and optimized formate oxidation activity. Replacement of the cysteine ligand by a formate (HCO2-) ligand at the molybdenum in active enzyme is compatible with our XAS data. Cyanide (CN-) inactivated the enzyme by replacing the sulfido ligand at Mo(VI) with an oxo ligand. Evidence that the sulfido group may become protonated upon molybdenum reduction was obtained. Our results emphasize the role of coordination flexibility at the molybdenum center during inhibitory and catalytic processes of FDH enzymes.
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Affiliation(s)
- Benjamin R Duffus
- Institut für Biochemie und Biologie, Molekulare Enzymologie , Universität Potsdam , Karl-Liebknecht Strasse 24-25 , 14476 Potsdam , Germany
| | - Peer Schrapers
- Institut für Experimentalphysik , Freie Universität Berlin , Arnimallee 14 , 14195 Berlin , Germany
| | - Nils Schuth
- Institut für Experimentalphysik , Freie Universität Berlin , Arnimallee 14 , 14195 Berlin , Germany
| | - Stefan Mebs
- Institut für Experimentalphysik , Freie Universität Berlin , Arnimallee 14 , 14195 Berlin , Germany
| | - Holger Dau
- Institut für Experimentalphysik , Freie Universität Berlin , Arnimallee 14 , 14195 Berlin , Germany
| | - Silke Leimkühler
- Institut für Biochemie und Biologie, Molekulare Enzymologie , Universität Potsdam , Karl-Liebknecht Strasse 24-25 , 14476 Potsdam , Germany
| | - Michael Haumann
- Institut für Experimentalphysik , Freie Universität Berlin , Arnimallee 14 , 14195 Berlin , Germany
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11
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Tran R, Kilyanek SM. Deoxydehydration of polyols catalyzed by a molybdenum dioxo-complex supported by a dianionic ONO pincer ligand. Dalton Trans 2019; 48:16304-16311. [PMID: 31621730 DOI: 10.1039/c9dt03759d] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Deoxydehydration (DODH) is the net reduction of diols and polyols to alkenes or dienes and water. Molybdenum cis-dioxo bis-phenolate ONO complexes were synthesized and have been shown to be active for DODH. Catalysts were screened for activity at 150-190 °C, and appreciable yields of up to 59% were obtained. PPh3, Na2SO3, Zn, C, 3-octanol and 2-propanol were screened as reductants. Additionally, the reactivities of a variety of diols were screened. With (R,R)-(+)-hydrobenzoin as substrate, DODH occurs via a mechanism where reduction of the Mo catalyst is a result of diol oxidation to form two equivalents of aldehyde. These reactions result in complete conversion and near quantitative yields of trans-stilbene and benzaldehyde.
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Affiliation(s)
- Randy Tran
- University of Arkansas, Fayetteville, AR 72701, USA.
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12
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Ehweiner MA, Vidovič C, Belaj F, Mösch-Zanetti NC. Bioinspired Tungsten Complexes Employing a Thioether Scorpionate Ligand. Inorg Chem 2019; 58:8179-8187. [PMID: 31141348 DOI: 10.1021/acs.inorgchem.9b00973] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The synthesis and characterization of a series of novel tungsten complexes employing the bioinspired, sulfur-rich scorpionate ligand [PhTt] (phenyltris((methylthio)methyl)borate) are reported. Starting from the previously published tungsten precursor [WBr2(CO)3(NCMe)2], a salt metathesis reaction with 1 equiv of Cs[PhTt] led to the desired complex [WBr(CO)3(PhTt)] (1), making it the first tungsten complex employing a poly(thioether)borate ligand. Surprisingly, the reaction of [WBr2(CO)3(NCMe)2] with an excess of the ligand gave complex [W(CO)2(η2-CH2SMe)(PhTt)] (2) with a bidentate (methylthio)methanide ligand as the major product. Thereby, phenyldi((methylthio)methyl)borane is formed, which was isolated and characterized by NMR spectroscopy. The bromido ligand in [WBr(CO)3(PhTt)] was further substituted by the S,N-bidentate methimazole in order to make the first coordination sphere more sulfur-rich forming [W(CO)2(mt)(PhTt)] (3). Alkyne tungsten complexes employing the sulfur-rich scorpionate ligand were accessible by reaction of [WBr2(CO)(C2R2)2(NCMe)] (R = Me, Ph) with Cs[PhTt] forming [WBr(CO)(C2R2)2(PhTt- S, S')] (R = Me 4, Ph 5), with the potentially tridentate ligand coordinated only via two sulfur atoms. In the case of 4, the higher flexibility of the bidentate coordination leads to the formation of two isomers with respect to the six-membered ring formed by the tungsten center and the two coordinated sulfur atoms of the ligand. All complexes 1-5 were characterized by single-crystal X-ray diffraction analysis.
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Affiliation(s)
- Madeleine A Ehweiner
- Institute of Chemistry, Inorganic Chemistry , University of Graz , Schubertstrasse 1 , 8010 Graz , Austria
| | - Carina Vidovič
- Institute of Chemistry, Inorganic Chemistry , University of Graz , Schubertstrasse 1 , 8010 Graz , Austria
| | - Ferdinand Belaj
- Institute of Chemistry, Inorganic Chemistry , University of Graz , Schubertstrasse 1 , 8010 Graz , Austria
| | - Nadia C Mösch-Zanetti
- Institute of Chemistry, Inorganic Chemistry , University of Graz , Schubertstrasse 1 , 8010 Graz , Austria
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13
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Peschel LM, Vidovič C, Belaj F, Neshchadin D, Mösch‐Zanetti NC. Activation and Photoinduced Release of Alkynes on a Biomimetic Tungsten Center: The Photochemical Behavior of the W-S-Phoz System. Chemistry 2019; 25:3893-3902. [PMID: 30773712 PMCID: PMC6563718 DOI: 10.1002/chem.201805665] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 12/13/2018] [Indexed: 01/09/2023]
Abstract
The synthesis and structural determination of four tungsten alkyne complexes coordinated by the bio-inspired S,N-donor ligand 2-(4',4'-dimethyloxazoline-2'-yl)thiophenolate (S-Phoz) is presented. A previously established protocol that involved the reaction of the respective alkyne with the bis-carbonyl precursor [W(CO)2 (S-Phoz)2 ] was used for the complexes [W(CO)(C2 R2 )(S-Phoz)2 ] (R=H, 1 a; Me, 1 b; Ph, 1 c). Oxidation with pyridine-N-oxide gave the corresponding W-oxo species [WO(C2 R2 )(S-Phoz)2 ] (R=H, 2 a; Me, 2 b; Ph, 2 c). All W-oxo-alkyne complexes (2 a, b, c) were found to be capable of alkyne release upon light irradiation to afford five-coordinate [WO(S-Phoz)2 ] (3). The photoinduced release of the alkyne ligand was studied in detail by in situ 1 H NMR measurements, which revealed correlation of the photodissociation rate constant (2 b>2 a>2 c) with the elongation of the alkyne C≡C bond in the molecular structures. Oxidation of [WO(S-Phoz)2 ] (3) with pyridine-N-oxide yielded [WO2 (S-Phoz)2 ] (4), which shows highly fluxional behavior in solution. Variable-temperature 1 H NMR spectroscopy revealed three isomeric forms with respect to the ligand arrangement versus each other. Furthermore, compound 4 rearranges to tetranuclear oxo compound [W4 O4 (μ-O)6 (S-Phoz)4 ] (5) and dinuclear [{WO(μ-O)(S-Phoz)}2 ] (6) over time. The latter two were identified by single-crystal X-ray diffraction analyses.
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Affiliation(s)
- Lydia M. Peschel
- Institute of ChemistryUniversity of GrazSchubertstrasse 18010GrazAustria
| | - Carina Vidovič
- Institute of ChemistryUniversity of GrazSchubertstrasse 18010GrazAustria
| | - Ferdinand Belaj
- Institute of ChemistryUniversity of GrazSchubertstrasse 18010GrazAustria
| | - Dmytro Neshchadin
- Institute of Physical and Theoretical ChemistryGraz University of TechnologyStremayrgasse 98010GrazAustria
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14
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Paudel J, Pokhrel A, Kirk ML, Li F. Remote Charge Effects on the Oxygen-Atom-Transfer Reactivity and Their Relationship to Molybdenum Enzymes. Inorg Chem 2019; 58:2054-2068. [PMID: 30673233 DOI: 10.1021/acs.inorgchem.8b03093] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report the syntheses, crystal structures, and characterization of the novel cis-dioxomolybdenum(VI) complexes [Tpm*MoVIO2Cl](MoO2Cl3) (1) and [Tpm*MoVIO2Cl](ClO4) (2), which are supported by the charge-neutral tris(3,5-dimethyl-1-pyrazolyl)methane (Tpm*) ligand. A comparison between isostructural [Tpm*MoVIO2Cl]+ and Tp*MoVIO2Cl [Tp* = hydrotris(3,5-dimethyl-1-pyrazolyl)borate] reveals the effects of one unit of overall charge difference on their spectroscopic and electrochemical properties, geometric and electronic structures, and O-atom-transfer (OAT) reactivities, providing new insight into pyranopterin molybdoenzyme OAT reactivity. Computational studies of these molecules indicate that the delocalized positive charge lowers the lowest unoccupied molecular orbital (LUMO) energy of cationic [Tpm*MoO2Cl]+ relative to Tp*MoO2Cl. Despite their virtually identical geometric structures revealed by crystal structures, the MoVI/MoV redox potential of 2 is increased by 350 mV relative to that of Tp*MoVIO2Cl. This LUMO stabilization also contributes to an increased effective electrophilicity of [Tpm*MoO2Cl]+ relative to that of Tp*MoO2Cl, resulting in a more favorable resonant interaction between the molydenum complex LUMO and the highest occupied molecular orbital (HOMO) of the PPh3 substrate. This leads to a greater thermodynamic driving force, an earlier transition state, and a lowered activation barrier for the orbitally controlled first step of the OAT reaction in the Tpm* system relative to the Tp* system. An Eyring plot analysis shows that this initial step yields an O≡MoIV-OPPh3 intermediate via an associative transition state, and the reaction is ∼500-fold faster for 2 than for Tp*MoO2Cl. The second step of the OAT reaction entails solvolysis of the O≡MoIV-OPPh3 intermediate to afford the solvent-substituted MoIV product and is 750-fold faster for the Tpm* system at -15 °C compared to the Tp* system. The observed rate enhancement for the second step is ascribed to a switch of the reaction mechanism from a dissociative pathway for the Tp* system to an alternative associative pathway for the Tpm* system. This is due to a more Lewis acidic MoIV center in the Tpm* system.
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Affiliation(s)
- Jaya Paudel
- Department of Chemistry and Biochemistry , New Mexico State University , Las Cruces , New Mexico 88003 , United States
| | - Amrit Pokhrel
- Department of Chemistry and Chemical Biology , The University of New Mexico , Albuquerque , New Mexico 87131 , United States
| | - Martin L Kirk
- Department of Chemistry and Chemical Biology , The University of New Mexico , Albuquerque , New Mexico 87131 , United States
| | - Feifei Li
- Department of Chemistry and Biochemistry , New Mexico State University , Las Cruces , New Mexico 88003 , United States
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15
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Sugimoto H, Sato M, Asano K, Suzuki T, Ogura T, Itoh S. Oxido-alcoholato/thiolato-molybdenum(VI) complexes with a dithiolene ligand generated by oxygen atom transfer to the molybdenum(IV) complexes. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2018.10.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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16
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17
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Saswati, Roy S, Dash SP, Acharyya R, Kaminsky W, Ugone V, Garribba E, Harris C, Lowe JM, Dinda R. Chemistry of oxidomolybdenum(IV) and -(VI) complexes with ONS donor ligands: Synthesis, computational evaluation and oxo-transfer reactions. Polyhedron 2018. [DOI: 10.1016/j.poly.2017.12.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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18
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Maurya MR, Mengesha B, Uprety B, Jangra N, Tomar R, Avecilla F. Oxygen atom transfer between DMSO and benzoin catalyzed by cis-dioxidomolybdenum(vi) complexes of tetradentate Mannich bases. NEW J CHEM 2018. [DOI: 10.1039/c7nj03551a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Dioxidomolybdenum(vi) complexes of tetradentate ONNO donor Mannich base ligands for the catalytic oxygen atom transfer between benzoin and DMSO are reported.
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Affiliation(s)
- Mannar R. Maurya
- Department of Chemistry, Indian Institute of Technology Roorkee
- Roorkee-247667
- India
| | - Bekele Mengesha
- Department of Chemistry, Indian Institute of Technology Roorkee
- Roorkee-247667
- India
| | - Bhawna Uprety
- Department of Chemistry, Indian Institute of Technology Roorkee
- Roorkee-247667
- India
| | - Nancy Jangra
- Department of Chemistry, Indian Institute of Technology Roorkee
- Roorkee-247667
- India
| | - Reshu Tomar
- Department of Chemistry, Indian Institute of Technology Roorkee
- Roorkee-247667
- India
| | - Fernando Avecilla
- Grupo Xenomar
- Centro de Investigacións Científicas Avanzadas (CICA)
- Departamento de Química
- Facultade de Ciencias
- Universidade da Coruña
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19
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Hollingsworth TS, Hollingsworth RL, Lord RL, Groysman S. Cooperative bimetallic reactivity of a heterodinuclear molybdenum–copper model of Mo–Cu CODH. Dalton Trans 2018; 47:10017-10024. [DOI: 10.1039/c8dt02323a] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Modeling the reactivity of Mo–Cu CODH: Cu(i) brings the substrate close to Mo–oxo and develops electrophilic character in CO carbon.
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Affiliation(s)
| | | | - Richard L. Lord
- Department of Chemistry
- Grand Valley State University
- Allendale
- USA
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20
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Acid-facilitated product release from a Mo(IV) center: relevance to oxygen atom transfer reactivity of molybdenum oxotransferases. J Biol Inorg Chem 2017; 23:193-207. [PMID: 29177705 DOI: 10.1007/s00775-017-1518-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 11/10/2017] [Indexed: 01/27/2023]
Abstract
We report that pyridinium ions (HPyr+) accelerate the conversion of [Tp*MoIVOCl(OPMe3)] (1) to [Tp*MoIVOCl(NCCH3)] (2) by 103-fold, affording 2 in near-quantitative yield; Tp* = hydrotris(3,5-dimethyl-1-pyrazolyl)borate. This novel reactivity and the mechanism of this reaction were investigated in detail. The formation of 2 followed pseudo-first-order kinetics, with the observed pseudo-first-order rate constant (k obs) linearly correlated with [HPyr+]. An Eyring plot revealed that this HPyr+-facilitated reaction has a small positive value of ∆S ‡ indicative of a dissociative interchange (Id) mechanism, different from the slower associative interchange (Ia) mechanism in the absence of HPyr+ marked with a negative ∆S ‡. Interestingly, log(k obs) was found to be linearly correlated to the acidity of substituted pyridinium ions. This novel reactivity is further investigated using combined DFT and ab initio coupled cluster methods. Different reaction pathways, including Id, Ia, and possible alternative routes in the absence or presence of HPyr+, were considered, and enthalpy and free energies were calculated for each pathway. Our computational results further underscored that the Id route is energetically favored in the presence of HPyr+, in contrast with the preferred Ia-NNO pathway in the absence of HPyr+. Our computational results also revealed molecular-level details for the HPyr+-facilitated Id route. Specifically, HPyr+ initially becomes hydrogen-bonded to the oxygen atom of the Mo(IV)-OPMe3 moiety, which lowers the activation barrier for the Mo-OPMe3 bond cleavage in a rate-limiting step to dissociate the OPMe3 product. The implications of our results were discussed in the context of molybdoenzymes, particularly the reductive half-reaction of sulfite oxidase.
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21
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Maurya MR, Rana L, Jangra N, Avecilla F. Bis{cis-[MoO2]} Complexes of 4,6-Diacetyl Resorcinol Bis(hydrazone)and Their Catalytic Application for the Three Components Dynamic Covalent Assembly via Hantzsch Reaction. ChemistrySelect 2017. [DOI: 10.1002/slct.201701629] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Mannar R. Maurya
- Department of Chemistry; Indian Institute of Technology Roorkee; Roorkee 247667 India
| | - Lata Rana
- Department of Chemistry; Indian Institute of Technology Roorkee; Roorkee 247667 India
| | - Nancy Jangra
- Department of Chemistry; Indian Institute of Technology Roorkee; Roorkee 247667 India
| | - Fernando Avecilla
- Grupo Xenomar; Centro de Investigacións Científicas Avanzadas (CICA); Departamento de Química; Facultade de Ciencias; Universidade da Coruña, Campus de A Coruña; 15071 A Coruña Spain
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22
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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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23
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Khatua S, Naskar T, Nandi C, Majumdar A. Mononuclear bis(dithiolene) Mo(iv) and W(iv) complexes with P,P; S,S; O,S and O,O donor ligands: a comparative reactivity study. NEW J CHEM 2017. [DOI: 10.1039/c7nj01797a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Comparative redox reactions of eight MoIV/WIVcomplexes with P,P; S,S; S,O and O,O donor ligands are presented.
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Affiliation(s)
- S. Khatua
- Department of Inorganic Chemistry
- Indian Association for the Cultivation of Science
- Kolkata 700032
- India
| | - T. Naskar
- Department of Inorganic Chemistry
- Indian Association for the Cultivation of Science
- Kolkata 700032
- India
| | - C. Nandi
- Department of Inorganic Chemistry
- Indian Association for the Cultivation of Science
- Kolkata 700032
- India
| | - A. Majumdar
- Department of Inorganic Chemistry
- Indian Association for the Cultivation of Science
- Kolkata 700032
- India
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24
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Maurya MR, Rana L, Avecilla F. Molybdenum complexes with a μ-O{MoO2}2 core: their synthesis, crystal structure and application as catalysts for the oxidation of bicyclic alcohols using N-based additives. NEW J CHEM 2017. [DOI: 10.1039/c6nj03162e] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Binuclear molybdenum(vi) complexes with a μ-O{MoO2}2 core as catalysts for the oxidation of bicyclic alcohols (fenchyl alcohol and isoborneol), using 30% H2O2 as the oxidant in the presence of NEt3 as the additive, are reported.
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Affiliation(s)
- Mannar R. Maurya
- Department of Chemistry
- Indian Institute of Technology Roorkee
- Roorkee 247667
- India
| | - Lata Rana
- Department of Chemistry
- Indian Institute of Technology Roorkee
- Roorkee 247667
- India
| | - Fernando Avecilla
- Departamento de Química Fundamental
- Universidade da Coruña
- Campus de A Zapateira
- 15071 A Coruña
- Spain
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25
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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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26
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Maurya MR, Uprety B, Avecilla F. Dioxidomolybdenum(VI) Complexes of Tripodal Tetradentate Ligands for Catalytic Oxygen Atom Transfer between Benzoin and Dimethyl Sulfoxide and for Oxidation of Pyrogallol. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201600694] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Mannar R. Maurya
- Department of Chemistry; Indian Institute of Technology Roorkee; 247667 Roorkee India
| | - Bhawna Uprety
- Department of Chemistry; Indian Institute of Technology Roorkee; 247667 Roorkee India
| | - Fernando Avecilla
- Departamento de Química Fundamental; Universidade da Coruña; Campus de A Zapateira 15071 A Coruña Spain
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27
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Affiliation(s)
- Charles G. Young
- Department of Chemistry and PhysicsLa Trobe Institute for Molecular ScienceLa Trobe University3086MelbourneVictoriaAustralia
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28
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Heinze K. Bioinspired functional analogs of the active site of molybdenum enzymes: Intermediates and mechanisms. Coord Chem Rev 2015. [DOI: 10.1016/j.ccr.2015.04.010] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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29
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Majumdar A. Bioinorganic modeling chemistry of carbon monoxide dehydrogenases: description of model complexes, current status and possible future scopes. Dalton Trans 2015; 43:12135-45. [PMID: 24984248 DOI: 10.1039/c4dt00729h] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Carbon monoxide dehydrogenases (CODHs) use CO as their sole source of carbon and energy and are found in both aerobic and anaerobic carboxidotrophic bacteria. Reversible transformation of CO to CO2 is catalyzed by a bimetallic [Mo-(μ2-S)-Cu] system in aerobic and by a highly asymmetric [Ni-Fe-S] cluster in anaerobic CODH active sites. The CODH activity in the microorganisms effects the removal of almost 10(8) tons of CO annually from the lower atmosphere and earth and thus help to maintain a sub-toxic concentration of CO. Despite an appreciable amount of work, the mechanism of CODH activity is not clearly understood yet. Moreover, biomimetic chemistry directed towards the active sites of CODHs faces several synthetic challenges. The synthetic problems associated with the modeling chemistry and strategies adopted to overcome those problems are discussed along with their limitations. A critical analysis of the exciting results delineating the present status of CODH modeling chemistry and its future prospects are presented.
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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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30
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Schrapers P, Hartmann T, Kositzki R, Dau H, Reschke S, Schulzke C, Leimkühler S, Haumann M. Sulfido and cysteine ligation changes at the molybdenum cofactor during substrate conversion by formate dehydrogenase (FDH) from Rhodobacter capsulatus. Inorg Chem 2015; 54:3260-71. [PMID: 25803130 DOI: 10.1021/ic502880y] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Formate dehydrogenase (FDH) enzymes are attractive catalysts for potential carbon dioxide conversion applications. The FDH from Rhodobacter capsulatus (RcFDH) binds a bis-molybdopterin-guanine-dinucleotide (bis-MGD) cofactor, facilitating reversible formate (HCOO(-)) to CO2 oxidation. We characterized the molecular structure of the active site of wildtype RcFDH and protein variants using X-ray absorption spectroscopy (XAS) at the Mo K-edge. This approach has revealed concomitant binding of a sulfido ligand (Mo=S) and a conserved cysteine residue (S(Cys386)) to Mo(VI) in the active oxidized molybdenum cofactor (Moco), retention of such a coordination motif at Mo(V) in a chemically reduced enzyme, and replacement of only the S(Cys386) ligand by an oxygen of formate upon Mo(IV) formation. The lack of a Mo=S bond in RcFDH expressed in the absence of FdsC implies specific metal sulfuration by this bis-MGD binding chaperone. This process still functioned in the Cys386Ser variant, showing no Mo-S(Cys386) ligand, but retaining a Mo=S bond. The C386S variant and the protein expressed without FdsC were inactive in formate oxidation, supporting that both Mo-ligands are essential for catalysis. Low-pH inhibition of RcFDH was attributed to protonation at the conserved His387, supported by the enhanced activity of the His387Met variant at low pH, whereas inactive cofactor species showed sulfido-to-oxo group exchange at the Mo ion. Our results support that the sulfido and S(Cys386) ligands at Mo and a hydrogen-bonded network including His387 are crucial for positioning, deprotonation, and oxidation of formate during the reaction cycle of RcFDH.
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Affiliation(s)
- Peer Schrapers
- †Institut für Experimentalphysik, Freie Universität Berlin, 14195 Berlin, Germany
| | - Tobias Hartmann
- ‡Institut für Biochemie und Biologie, Molekulare Enzymologie, Universität Potsdam, 14476 Potsdam, Germany
| | - Ramona Kositzki
- †Institut für Experimentalphysik, Freie Universität Berlin, 14195 Berlin, Germany
| | - Holger Dau
- †Institut für Experimentalphysik, Freie Universität Berlin, 14195 Berlin, Germany
| | - Stefan Reschke
- ‡Institut für Biochemie und Biologie, Molekulare Enzymologie, Universität Potsdam, 14476 Potsdam, Germany
| | - Carola Schulzke
- §Institut für Biochemie, Bioanorganische Chemie, Ernst-Moritz-Arndt-Universität Greifswald, 17487 Greifswald, 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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31
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Basu P, Nieter Burgmayer SJ. Recent developments in the study of molybdoenzyme models. J Biol Inorg Chem 2015; 20:373-83. [PMID: 25578808 PMCID: PMC4336637 DOI: 10.1007/s00775-014-1228-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2014] [Accepted: 12/07/2014] [Indexed: 12/22/2022]
Abstract
Over the past two decades, a plethora of crystal structures of molybdenum enzymes has appeared in the literature providing a clearer picture of the enzymatic active sites and increasing the challenge to chemists to develop accurate models for those sites. In this minireview we discuss the most recent model studies aimed to reproduce detailed features of the pterin-dithiolene ligand, both as the uncoordinated form and as a chelate coordinated to molybdenum.
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Affiliation(s)
- Partha Basu
- Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, PA 15282
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