301
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Bruschi M, Greco C, Kaukonen M, Fantucci P, Ryde U, De Gioia L. Influence of the [2Fe]HSubcluster Environment on the Properties of Key Intermediates in the Catalytic Cycle of [FeFe] Hydrogenases: Hints for the Rational Design of Synthetic Catalysts. Angew Chem Int Ed Engl 2009; 48:3503-6. [DOI: 10.1002/anie.200900494] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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302
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Liptak MD, Van Heuvelen KM, Brunold* TC. Computational Studies of Bioorganometallic Enzymes and Cofactors. METAL-CARBON BONDS IN ENZYMES AND COFACTORS 2009. [DOI: 10.1039/9781847559333-00417] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Because of their complex geometric and electronic structures, the active sites and cofactors of bioorganometallic enzymes, which are characterized by their metal–carbon bonds, pose a major challenge for computational chemists. However, recent progress in computer technology and theoretical chemistry, along with insights gained from mechanistic, spectroscopic, and X-ray crystallographic studies, have established an excellent foundation for the successful completion of computational studies aimed at elucidating the electronic structures and catalytic cycles of these species. This chapter briefly reviews the most popular computational approaches employed in theoretical studies of bioorganometallic species and summarizes important information obtained from computational studies of (i) the enzymatic formation and cleavage of the Co–C bond of coenzyme B12; (ii) the catalytic cycle of methyl-coenzyme M reductase and its nickel-containing cofactor F430; (iii) the polynuclear active-site clusters of the bifunctional enzyme carbon monoxide dehydrogenase/acetyl-coenzyme A synthase; and (iv) the magnetic properties of the active-site cluster of Fe-only hydrogenases.
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Affiliation(s)
- Matthew D. Liptak
- Department of Chemistry, University of Wisconsin-Madison Madison WI 53706 USA
| | | | - Thomas C. Brunold*
- Department of Chemistry, University of Wisconsin-Madison Madison WI 53706 USA
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303
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An Autocatalytic Mechanism for NiFe-Hydrogenase: Reduction to Ni(I) Followed by Oxidative Addition. Biochemistry 2009; 48:1056-66. [DOI: 10.1021/bi801218n] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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304
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Green KN, Hess JL, Thomas CM, Darensbourg MY. Resin-bound models of the [FeFe]-hydrogenase enzyme active site and studies of their reactivity. Dalton Trans 2009:4344-50. [DOI: 10.1039/b823152d] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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305
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Abstract
This tutorial review is aimed at chemical scientists interested in understanding and exploiting the remarkable catalytic behavior of the hydrogenases. The key structural features are analyzed for the active sites of the two most important hydrogenases. Reactivity is emphasized, focusing on mechanism and catalysis. Through this analysis, gaps are identified in the synthesis of functional replicas of these fascinating and potentially useful enzymes.
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Affiliation(s)
- Frédéric Gloaguen
- UMR CNRS 6521, Université de Bretagne Occidentale, CS 93837, 29238 Brest cedex 3, France.
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306
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307
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Angamuthu R, Gelauff LL, Siegler MA, Spek AL, Bouwman E. A molecular cage of nickel(ii) and copper(i): a [{Ni(L)2}2(CuI)6] cluster resembling the active site of nickel-containing enzymes. Chem Commun (Camb) 2009:2700-2. [DOI: 10.1039/b900423h] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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308
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Ogata H, Lubitz W, Higuchi Y. [NiFe] hydrogenases: structural and spectroscopic studies of the reaction mechanism. Dalton Trans 2009:7577-87. [DOI: 10.1039/b903840j] [Citation(s) in RCA: 168] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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309
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Besora M, Lledós A, Maseras F. Protonation of transition-metal hydrides: a not so simple process. Chem Soc Rev 2009; 38:957-66. [DOI: 10.1039/b608404b] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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310
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Siegbahn PEM. A structure-consistent mechanism for dioxygen formation in photosystem II. Chemistry 2008; 14:8290-302. [PMID: 18680116 DOI: 10.1002/chem.200800445] [Citation(s) in RCA: 198] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In recent DFT studies a new mechanism for O-O bond formation at the oxygen evolving center (OEC) in photosystem II has been suggested. With the structure of the S(4) state required for that mechanism, the structures of the lower S states are investigated herein by adding protons and electrons. A model was used including the full amino acids for the ones ligating the OEC, and in which the backbone positions were held fixed from the X-ray structure. The only charged second-shell ligand Arg357 was also included. An optimized structure for the S(1) state was reached with a large similarity to one of those suggested by EXAFS. A full catalytic cycle was derived which can rationalize the structural relaxation in the S(2) to S(3) transition, and the fact that only an electron leaves in the transition before. Water is suggested to bind to the OEC in the S(2) to S(3), and S(4) to S(0) transitions. A new possibility for water exchange is suggested from the final energy diagram. The optimal O-O bond formation occurs between an oxygen radical and an oxo ligand. The alternative mechanism, where the oxygen radical reacts with an external water, has a barrier about 20 kcal mol(-1) higher.
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Affiliation(s)
- Per E M Siegbahn
- Department of Physics, ALBA NOVA, Stockholm University, 106 91 Stockholm, Sweden.
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311
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Petro BJ, Vannucci AK, Lockett LT, Mebi C, Kottani R, Gruhn NE, Nichol GS, Goodyer PA, Evans DH, Glass RS, Lichtenberger DL. Photoelectron spectroscopy of dithiolatodiironhexacarbonyl models for the active site of [Fe–Fe] hydrogenases: Insight into the reorganization energy of the “rotated” structure in the enzyme. J Mol Struct 2008. [DOI: 10.1016/j.molstruc.2008.04.024] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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312
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Yang X, Hall MB. Trigger Mechanism for the Catalytic Hydrogen Activation by Monoiron (Iron−Sulfur Cluster-Free) Hydrogenase. J Am Chem Soc 2008; 130:14036-7. [DOI: 10.1021/ja804364p] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Xinzheng Yang
- Department of Chemistry, Texas A&M University, College Station, Texas 77843-3255
| | - Michael B. Hall
- Department of Chemistry, Texas A&M University, College Station, Texas 77843-3255
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313
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Sbraccia C, Zipoli F, Car R, Cohen MH, Dismukes GC, Selloni A. Mechanism of H2 Production by the [FeFe]H Subcluster of Di-Iron Hydrogenases: Implications for Abiotic Catalysts. J Phys Chem B 2008; 112:13381-90. [DOI: 10.1021/jp803657b] [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)
- Carlo Sbraccia
- Department of Chemistry and Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey, 08544, and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey, 08854
| | - Federico Zipoli
- Department of Chemistry and Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey, 08544, and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey, 08854
| | - Roberto Car
- Department of Chemistry and Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey, 08544, and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey, 08854
| | - Morrel H. Cohen
- Department of Chemistry and Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey, 08544, and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey, 08854
| | - G. Charles Dismukes
- Department of Chemistry and Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey, 08544, and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey, 08854
| | - Annabella Selloni
- Department of Chemistry and Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey, 08544, and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey, 08854
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314
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Olsen MT, Bruschi M, De Gioia L, Rauchfuss TB, Wilson SR. Nitrosyl derivatives of diiron(I) dithiolates mimic the structure and Lewis acidity of the [FeFe]-hydrogenase active site. J Am Chem Soc 2008; 130:12021-30. [PMID: 18700771 PMCID: PMC2574744 DOI: 10.1021/ja802268p] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This study probes the impact of electronic asymmetry of diiron(I) dithiolato carbonyls. Treatment of Fe2(S2C(n)H(2n))(CO)(6-x)(PMe3)x compounds (n = 2, 3; x = 1, 2, 3) with NOBF4 gave the derivatives [Fe2(S2C(n)H(2n))(CO)(5-x)(PMe3)x(NO)]BF4, which are electronically unsymmetrical because of the presence of a single NO(+) ligand. Whereas the monophosphine derivative is largely undistorted, the bis(PMe3) derivatives are distorted such that the CO ligand on the Fe(CO)(PMe3)(NO)(+) subunit is semibridging. Two isomers of [Fe2(S2C3H6)(CO)3(PMe3)2(NO)]BF4 were characterized spectroscopically and crystallographically. Each isomer features electron-rich Fe(CO)2PMe3 and electrophilic Fe(CO)(PMe3)(NO)(+) subunits. These species are in equilibrium with an unobserved isomer that reversibly binds CO (DeltaH = -35 kJ/mol, DeltaS = -139 J mol(-1) K(-1)) to give the symmetrical adduct [Fe2(S2C3H6)(mu-NO)(CO)4(PMe3)2]BF4. In contrast to Fe2(S2C3H6)(CO)4(PMe3)2, the bis(PMe3) nitrosyl complexes readily undergo CO substitution to give the (PMe3)3 derivatives. The nitrosyl complexes reduce at potentials that are approximately 1 V milder than their carbonyl counterparts. Results of density functional theory calculations, specifically natural bond orbital analysis, reinforce the electronic resemblance of the nitrosyl complexes to the corresponding mixed-valence diiron complexes. Unlike other diiron dithiolato carbonyls, these species undergo reversible reductions at mild potentials. The results show that the novel structural and chemical features associated with mixed-valence diiron dithiolates (the so-called H(ox) models) can be replicated in the absence of mixed-valency by the introduction of electronic asymmetry.
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Affiliation(s)
- Matthew T. Olsen
- Department of Chemistry, University of Illinois at Urbana -- Champaign, Urbana, Illinois, 61801
- Department of Biotechnology and Biosciences, University of Milano—Bicocca, Piazza della Scienza 1, 20126-Milan, Italy
| | - Maurizio Bruschi
- Department of Chemistry, University of Illinois at Urbana -- Champaign, Urbana, Illinois, 61801
- Department of Biotechnology and Biosciences, University of Milano—Bicocca, Piazza della Scienza 1, 20126-Milan, Italy
| | - Luca De Gioia
- Department of Chemistry, University of Illinois at Urbana -- Champaign, Urbana, Illinois, 61801
- Department of Biotechnology and Biosciences, University of Milano—Bicocca, Piazza della Scienza 1, 20126-Milan, Italy
| | - Thomas B. Rauchfuss
- Department of Chemistry, University of Illinois at Urbana -- Champaign, Urbana, Illinois, 61801
- Department of Biotechnology and Biosciences, University of Milano—Bicocca, Piazza della Scienza 1, 20126-Milan, Italy
| | - Scott R. Wilson
- Department of Chemistry, University of Illinois at Urbana -- Champaign, Urbana, Illinois, 61801
- Department of Biotechnology and Biosciences, University of Milano—Bicocca, Piazza della Scienza 1, 20126-Milan, Italy
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315
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Ohki Y, Sakamoto M, Tatsumi K. Reversible Heterolysis of H2 Mediated by an M−S(Thiolate) Bond (M = Ir, Rh): A Mechanistic Implication for [NiFe] Hydrogenase. J Am Chem Soc 2008; 130:11610-1. [DOI: 10.1021/ja804848w] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yasuhiro Ohki
- Department of Chemistry and Graduate School of Science and Research Center for Meterials Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
| | - Mayumi Sakamoto
- Department of Chemistry and Graduate School of Science and Research Center for Meterials Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
| | - Kazuyuki Tatsumi
- Department of Chemistry and Graduate School of Science and Research Center for Meterials Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
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316
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Density functional theory on the larger active site models for [NiFe] hydrogenases: Two-state reactivity? CR CHIM 2008. [DOI: 10.1016/j.crci.2008.04.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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317
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Song LC, Zeng GH, Lou SX, Zan HN, Ming JB, Hu QM. Synthetic and Structural Studies of Butterfly Fe/S/P Cluster Complexes Related to the Active Site of [FeFe]-Hydrogenases. Proton Reduction to H2 Catalyzed by (η1-Ph2PS-η1)2Fe2(CO)6. Organometallics 2008. [DOI: 10.1021/om800077c] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Li-Cheng Song
- Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, People's Republic of China
| | - Guang-Huai Zeng
- Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, People's Republic of China
| | - Shao-Xia Lou
- Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, People's Republic of China
| | - Hui-Ning Zan
- Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, People's Republic of China
| | - Jiang-Bo Ming
- Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, People's Republic of China
| | - Qing-Mei Hu
- Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, People's Republic of China
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318
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Volkers PI, Boyke CA, Chen J, Rauchfuss TB, Whaley CM, Wilson SR, Yao H. Precursors to [FeFe]-hydrogenase models: syntheses of Fe2(SR)2(CO)6 from CO-free iron sources. Inorg Chem 2008; 47:7002-8. [PMID: 18610969 DOI: 10.1021/ic800601k] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This report describes routes to iron dithiolato carbonyls that do not require preformed iron carbonyls. The reaction of FeCl 2, Zn, and Q 2S 2C n H 2 n (Q (+) = Na (+), Et 3NH (+)) under an atmosphere of CO affords Fe 2(S 2C n H 2 n )(CO) 6 ( n = 2, 3) in yields >70%. The method was employed to prepare Fe 2(S 2C 2H 4)( (13)CO) 6. Treatment of these carbonylated mixtures with tertiary phosphines, instead of Zn, gave the ferrous species Fe 3(S 2C 3H 6) 3(CO) 4(PR 3) 2, for R = Et, Bu, and Ph. Like the related complex Fe 3(SPh) 6(CO) 6, these compounds consist of a linear arrangement of three conjoined face-shared octahedral centers. Omitting the phosphine but with an excess of dithiolate, we obtained the related mixed-valence triiron species [Fe 3(S 2C n H 2 n ) 4(CO) 4] (-). The highly reducing all-ferrous species [Fe 3(S 2C n H 2 n ) 4(CO) 4] (2-) is implicated as an intermediate in this transformation. Reactive forms of iron, prepared by the method of Rieke, also combined with dithiols under a CO atmosphere to give Fe 2(S 2C n H 2 n )(CO) 6 in modest yields under mild conditions. Studies on the order of addition indicate that ferrous thiolates are formed prior to the onset of carbonylation. Crystallographic characterization demonstrated that the complexes Fe 3(S 2C 3H 6) 3(CO) 4(PEt 3) 2 and PBnPh 3[Fe 3(S 2C 3H 6) 4(CO) 4] feature high-spin ferrous and low-spin ferric as the central metal, respectively.
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Affiliation(s)
- Phillip I Volkers
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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319
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Kaukonen M, Söderhjelm P, Heimdal J, Ryde U. Proton Transfer at Metal Sites in Proteins Studied by Quantum Mechanical Free-Energy Perturbations. J Chem Theory Comput 2008; 4:985-1001. [DOI: 10.1021/ct700347h] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Markus Kaukonen
- Department of Theoretical Chemistry, Lund University, Chemical Centre, P.O. Box 124, SE-221 00 Lund, Sweden
| | - Pär Söderhjelm
- Department of Theoretical Chemistry, Lund University, Chemical Centre, P.O. Box 124, SE-221 00 Lund, Sweden
| | - Jimmy Heimdal
- Department of Theoretical Chemistry, Lund University, Chemical Centre, P.O. Box 124, SE-221 00 Lund, Sweden
| | - Ulf Ryde
- Department of Theoretical Chemistry, Lund University, Chemical Centre, P.O. Box 124, SE-221 00 Lund, Sweden
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320
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Christensen CH, Nørskov JK. A molecular view of heterogeneous catalysis. J Chem Phys 2008; 128:182503. [DOI: 10.1063/1.2839299] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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321
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Justice AK, Nilges MJ, Rauchfuss TB, Wilson SR, De Gioia L, Zampella G. Diiron dithiolato carbonyls related to the H(ox)CO state of [FeFe]-hydrogenase. J Am Chem Soc 2008; 130:5293-301. [PMID: 18341276 PMCID: PMC2435217 DOI: 10.1021/ja7113008] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Oxidation of the electron-rich (E(1/2) = -175 vs Ag/AgCl) ethanedithiolato complex Fe2(S2C2H4)(CO)2(dppv)2 (1) under a CO atmosphere yielded [Fe2(S2C2H4)(mu-CO)(CO)2(dppv)2](+) ([1(CO)](+)), a model for the H(ox)(CO) state of the [FeFe]-hydrogenases. This complex exists as two isomers: a kinetically favored unsymmetrical derivative, unsym-[1(CO)](+), and a thermodynamically favored isomer, sym-[1(CO)](+), wherein both diphosphines span apical and basal sites. Crystallographic characterization of sym-[1(CO)](+) confirmed a C2-symmetric structure with a bridging CO ligand and an elongated Fe-Fe bond of 2.7012(14) A, as predicted previously. Oxidation of sym-[1(CO)](+) and unsym-[1(CO)](+) again by 1e(-) oxidation afforded the respective diamagnetic diferrous derivatives where the relative stabilities of the sym and unsym isomers are reversed. DFT calculations indicate that the stabilities of sym and unsym isomers are affected differently by the oxidation state of the diiron unit: the mutually trans CO ligands in the sym isomer are more destabilizing in the mixed-valence state than in the diferrous state. EPR analysis of mixed-valence complexes revealed that, for [1](+), the unpaired spin is localized on a single iron center, whereas for unsym/sym-[1(CO)](+), the unpaired spin was delocalized over both iron centers, as indicated by the magnitude of the hyperfine coupling to the phosphine ligands trans to the Fe-Fe vector. Oxidation of 1 by 2 equiv of acetylferrocenium afforded the dication [1](2+), which, on the basis of low-temperature IR spectrum, is structurally similar to [1](+). Treatment of [1](2+) with CO gives unsym-[1(CO)](2+).
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Affiliation(s)
- Aaron K Justice
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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322
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Barton BE, Rauchfuss TB. Terminal hydride in [FeFe]-hydrogenase model has lower potential for H2 production than the isomeric bridging hydride. Inorg Chem 2008; 47:2261-3. [PMID: 18333613 DOI: 10.1021/ic800030y] [Citation(s) in RCA: 167] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Protonation of the symmetrical tetraphosphine complexes Fe2(S2CnH2n)(CO)2(dppv)2 afforded the corresponding terminal hydrides, establishing that even symmetrical diiron(I) dithiolates undergo protonation at terminal sites. The terminal hydride [HFe2(S2C3H6)(CO)2(dppv)2](+) was found to catalyze proton reduction at potentials 200 mV milder than the isomeric bridging hydride, thereby establishing a thermodynamic advantage for catalysis operating via terminal hydride. The azadithiolate protonates to afford, [Fe2[(SCH2)2NH2](CO)2(dppv)2](+), [HFe2[(SCH2)2NH](CO)2(dppv)2](+), and [HFe2[(SCH2)2NH2](CO)2(dppv)2](2+), depending on conditions.
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Affiliation(s)
- Bryan E Barton
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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323
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Jayapal P, Sundararajan M, Hillier IH, Burton NA. QM/MM studies of Ni–Fe hydrogenases: the effect of enzyme environment on the structure and energies of the inactive and active states. Phys Chem Chem Phys 2008; 10:4249-57. [DOI: 10.1039/b804035d] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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