151
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Massie AA, Denler MC, Cardoso LT, Walker AN, Hossain MK, Day VW, Nordlander E, Jackson TA. Equatorial Ligand Perturbations Influence the Reactivity of Manganese(IV)-Oxo Complexes. Angew Chem Int Ed Engl 2017; 56:4178-4182. [PMID: 28300349 DOI: 10.1002/anie.201612309] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 02/03/2017] [Indexed: 11/06/2022]
Abstract
Manganese(IV)-oxo complexes are often invoked as intermediates in Mn-catalyzed C-H bond activation reactions. While many synthetic MnIV -oxo species are mild oxidants, other members of this class can attack strong C-H bonds. The basis for these reactivity differences is not well understood. Here we describe a series of MnIV -oxo complexes with N5 pentadentate ligands that modulate the equatorial ligand field of the MnIV center, as assessed by electronic absorption, electron paramagnetic resonance, and Mn K-edge X-ray absorption methods. Kinetic experiments show dramatic rate variations in hydrogen-atom and oxygen-atom transfer reactions, with faster rates corresponding to weaker equatorial ligand fields. For these MnIV -oxo complexes, the rate enhancements are correlated with both 1) the energy of a low-lying 4 E excited state, which has been postulated to be involved in a two-state reactivity model, and 2) the MnIII/IV reduction potentials.
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Affiliation(s)
- Allyssa A Massie
- Department of Chemistry, University of Kansas, Lawrence, KS, USA
| | - Melissa C Denler
- Department of Chemistry, University of Kansas, Lawrence, KS, USA
| | | | - Ashlie N Walker
- Department of Chemistry, University of Kansas, Lawrence, KS, USA
| | - M Kamal Hossain
- Chemical Physics, Department of Chemistry, Lund University, Box 124, 22100, Lund, Sweden
| | - Victor W Day
- Department of Chemistry, University of Kansas, Lawrence, KS, USA
| | - Ebbe Nordlander
- Chemical Physics, Department of Chemistry, Lund University, Box 124, 22100, Lund, Sweden
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152
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Devi T, Lee Y, Jung J, Sankaralingam M, Nam W, Fukuzumi S. A Chromium(III)‐Superoxo Complex as a Three‐Electron Oxidant with a Large Tunneling Effect in Multi‐Electron Oxidation of NADH Analogues. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201611709] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Tarali Devi
- Department of Chemistry and Nano Science Ewha Womans University Seoul 03760 Korea
| | - Yong‐Min Lee
- Department of Chemistry and Nano Science Ewha Womans University Seoul 03760 Korea
| | - Jieun Jung
- Department of Chemistry and Nano Science Ewha Womans University Seoul 03760 Korea
| | | | - Wonwoo Nam
- Department of Chemistry and Nano Science Ewha Womans University Seoul 03760 Korea
- State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China
| | - Shunichi Fukuzumi
- Department of Chemistry and Nano Science Ewha Womans University Seoul 03760 Korea
- Faculty of Science and Engineering SENTAN Japan Science and Technology Agency (JST) Meijo University Nagoya, Aichi 468-8502 Japan
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153
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Devi T, Lee YM, Jung J, Sankaralingam M, Nam W, Fukuzumi S. A Chromium(III)-Superoxo Complex as a Three-Electron Oxidant with a Large Tunneling Effect in Multi-Electron Oxidation of NADH Analogues. Angew Chem Int Ed Engl 2017; 56:3510-3515. [PMID: 28266771 DOI: 10.1002/anie.201611709] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 01/15/2017] [Indexed: 11/06/2022]
Abstract
Metal-superoxo species are involved in a variety of enzymatic oxidation reactions, and multi-electron oxidation of substrates is frequently observed in those enzymatic reactions. A CrIII -superoxo complex, [CrIII (O2 )(TMC)(Cl)]+ (1; TMC=1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane), is described that acts as a novel three-electron oxidant in the oxidation of dihydronicotinamide adenine dinucleotide (NADH) analogues. In the reactions of 1 with NADH analogues, a CrIV -oxo complex, [CrIV (O)(TMC)(Cl)]+ (2), is formed by a heterolytic O-O bond cleavage of a putative CrII -hydroperoxo complex, [CrII (OOH)(TMC)(Cl)], which is generated by hydride transfer from NADH analogues to 1. The comparison of the reactivity of NADH analogues with 1 and p-chloranil (Cl4 Q) indicates that oxidation of NADH analogues by 1 proceeds by proton-coupled electron transfer with a very large tunneling effect (for example, with a kinetic isotope effect of 470 at 233 K), followed by rapid electron transfer.
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Affiliation(s)
- Tarali Devi
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 03760, Korea
| | - Yong-Min Lee
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 03760, Korea
| | - Jieun Jung
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 03760, Korea
| | | | - Wonwoo Nam
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 03760, Korea.,State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Shunichi Fukuzumi
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 03760, Korea.,Faculty of Science and Engineering, SENTAN Japan Science and Technology Agency (JST), Meijo University, Nagoya, Aichi, 468-8502, Japan
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154
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Bigelow JO, England J, Klein JEMN, Farquhar ER, Frisch JR, Martinho M, Mandal D, Münck E, Shaik S, Que L. Oxoiron(IV) Tetramethylcyclam Complexes with Axial Carboxylate Ligands: Effect of Tethering the Carboxylate on Reactivity. Inorg Chem 2017; 56:3287-3301. [DOI: 10.1021/acs.inorgchem.6b02659] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jennifer O. Bigelow
- Department of Chemistry
and Center for Metals in Biocatalysis, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Jason England
- Department of Chemistry
and Center for Metals in Biocatalysis, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Johannes E. M. N. Klein
- Department of Chemistry
and Center for Metals in Biocatalysis, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Erik R. Farquhar
- Department of Chemistry
and Center for Metals in Biocatalysis, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Jonathan R. Frisch
- Department of Chemistry
and Center for Metals in Biocatalysis, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Marlène Martinho
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Debasish Mandal
- Institute of Chemistry and the Lise Meitner-Minerva
Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem, 91904 Jerusalem, Israel
| | - Eckard Münck
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Sason Shaik
- Institute of Chemistry and the Lise Meitner-Minerva
Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem, 91904 Jerusalem, Israel
| | - Lawrence Que
- Department of Chemistry
and Center for Metals in Biocatalysis, University of Minnesota, Minneapolis, Minnesota 55455, United States
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155
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Yamagishi H, Konuma H, Kuwata S. Stereoselective synthesis of chlorido–phosphine ruthenium complexes bearing a pyrazole-based protic tripodal amine ligand. Polyhedron 2017. [DOI: 10.1016/j.poly.2016.11.037] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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156
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Chou KW, Su WJ, Huang HF, Zou XR, Chang YN, Lee PY, Liang LC. Titanium, hafnium, and tantalum complexes of a potentially triphenolate phosphine ligand that is unexpectedly prone to O-protonation. Polyhedron 2017. [DOI: 10.1016/j.poly.2016.11.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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157
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Andris E, Navrátil R, Jašík J, Terencio T, Srnec M, Costas M, Roithová J. Chasing the Evasive Fe═O Stretch and the Spin State of the Iron(IV)-Oxo Complexes by Photodissociation Spectroscopy. J Am Chem Soc 2017; 139:2757-2765. [PMID: 28125220 DOI: 10.1021/jacs.6b12291] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
We demonstrate the application of infrared photodissocation spectroscopy for determination of the Fe═O stretching frequencies of high-valent iron(IV)-oxo complexes [(L)Fe(O)(X)]2+/+ (L = TMC, N4Py, PyTACN, and X = CH3CN, CF3SO3, ClO4, CF3COO, NO3, N3). We show that the values determined by resonance Raman spectroscopy in acetonitrile solutions are on average 9 cm-1 red-shifted with respect to unbiased gas-phase values. Furthermore, we show the assignment of the spin state of the complexes based on the vibrational modes of a coordinated anion and compare reactivities of various iron(IV)-oxo complexes generated as dications or monocations (bearing an anionic ligand). The coordinated anions can drastically affect the reactivity of the complex and should be taken into account when comparing reactivities of complexes bearing different ligands. Comparison of reactivities of [(PyTACN)Fe(O)(X)]+ generated in different spin states and bearing different anionic ligands X revealed that the nature of anion influences the reactivity more than the spin state. The triflate and perchlorate ligands tend to stabilize the quintet state of [(PyTACN)Fe(O)(X)]+, whereas trifluoroacetate and nitrate stabilize the triplet state of the complex.
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Affiliation(s)
- Erik Andris
- Department of Organic Chemistry, Faculty of Science, Charles University , Hlavova 2030/8, 12843 Prague 2, Czech Republic
| | - Rafael Navrátil
- Department of Organic Chemistry, Faculty of Science, Charles University , Hlavova 2030/8, 12843 Prague 2, Czech Republic
| | - Juraj Jašík
- Department of Organic Chemistry, Faculty of Science, Charles University , Hlavova 2030/8, 12843 Prague 2, Czech Republic
| | - Thibault Terencio
- Department of Organic Chemistry, Faculty of Science, Charles University , Hlavova 2030/8, 12843 Prague 2, Czech Republic
| | - Martin Srnec
- J. Heyrovsky Institute of Physical Chemistry of the CAS , v.v i., Dolejškova 2155/3, 182 23 Prague 8, Czech Republic
| | - Miquel Costas
- Departament de Quimica and Institute of Computational Chemistry and Catalysis (IQCC), University of Girona , Campus Montilivi, Girona 17071, Spain
| | - Jana Roithová
- Department of Organic Chemistry, Faculty of Science, Charles University , Hlavova 2030/8, 12843 Prague 2, Czech Republic
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158
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High-valent metal-oxo complexes generated in catalytic oxidation reactions using water as an oxygen source. Coord Chem Rev 2017. [DOI: 10.1016/j.ccr.2016.09.018] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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159
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Oxidation of alkane and alkene moieties with biologically inspired nonheme iron catalysts and hydrogen peroxide: from free radicals to stereoselective transformations. J Biol Inorg Chem 2017; 22:425-452. [DOI: 10.1007/s00775-016-1434-z] [Citation(s) in RCA: 123] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 12/27/2016] [Indexed: 11/26/2022]
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160
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Impeng S, Siwaipram S, Bureekaew S, Probst M. Ethane C–H bond activation on the Fe(iv)–oxo species in a Zn-based cluster of metal–organic frameworks: a density functional theory study. Phys Chem Chem Phys 2017; 19:3782-3791. [DOI: 10.1039/c6cp07771d] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The generation of a Fe(iv)–oxo complex and its reactivity for C–H bond activation of ethane have been theoretically unraveled.
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Affiliation(s)
- Sarawoot Impeng
- Department of Chemical and Biomolecular Engineering
- School of Energy Science and Engineering
- Vidyasirimedhi Institute of Science and Technology
- Rayong 21210
- Thailand
| | - Siwarut Siwaipram
- Department of Chemical and Biomolecular Engineering
- School of Energy Science and Engineering
- Vidyasirimedhi Institute of Science and Technology
- Rayong 21210
- Thailand
| | - Sareeya Bureekaew
- Department of Chemical and Biomolecular Engineering
- School of Energy Science and Engineering
- Vidyasirimedhi Institute of Science and Technology
- Rayong 21210
- Thailand
| | - Michael Probst
- Institute of Ion Physics and Applied Physics
- University of Innsbruck
- 6020 Innsbruck
- Austria
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161
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Hickey AK, Lutz SA, Chen CH, Smith JM. Two-state reactivity in C–H activation by a four-coordinate iron(0) complex. Chem Commun (Camb) 2017; 53:1245-1248. [DOI: 10.1039/c6cc09244f] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The ground state structure of [Ph2B(tBuIm)2Fe(CO)2]− is trigonal pyramidal (S = 1), with a thermally accessible square planar (S = 0) geometry.
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Affiliation(s)
| | - Sean A. Lutz
- Department of Chemistry
- Indiana University
- Bloomington
- USA
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162
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Sankaralingam M, Lee YM, Lu X, Vardhaman AK, Nam W, Fukuzumi S. Autocatalytic dioxygen activation to produce an iron(v)-oxo complex without any reductants. Chem Commun (Camb) 2017; 53:8348-8351. [DOI: 10.1039/c7cc03742b] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An iron(v)-oxo complex with a tetraamido macrocyclic ligand, [(TAML)FeV(O)]−, was produced by reacting [(TAML)FeIII]− with dioxygen without any electron source in acetone at 298 K.
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Affiliation(s)
| | - Yong-Min Lee
- Department of Chemistry and Nano Science
- Ewha Womans University
- Seoul 03760
- Korea
| | - Xiaoyan Lu
- Department of Chemistry and Nano Science
- Ewha Womans University
- Seoul 03760
- Korea
| | | | - Wonwoo Nam
- Department of Chemistry and Nano Science
- Ewha Womans University
- Seoul 03760
- Korea
| | - Shunichi Fukuzumi
- Department of Chemistry and Nano Science
- Ewha Womans University
- Seoul 03760
- Korea
- Faculty of Science and Engineering
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163
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Villar-Acevedo G, Lugo-Mas P, Blakely MN, Rees JA, Ganas AS, Hanada EM, Kaminsky W, Kovacs JA. Metal-Assisted Oxo Atom Addition to an Fe(III) Thiolate. J Am Chem Soc 2016; 139:119-129. [PMID: 28033001 DOI: 10.1021/jacs.6b03512] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Cysteinate oxygenation is intimately tied to the function of both cysteine dioxygenases (CDOs) and nitrile hydratases (NHases), and yet the mechanisms by which sulfurs are oxidized by these enzymes are unknown, in part because intermediates have yet to be observed. Herein, we report a five-coordinate bis-thiolate ligated Fe(III) complex, [FeIII(S2Me2N3(Pr,Pr))]+ (2), that reacts with oxo atom donors (PhIO, IBX-ester, and H2O2) to afford a rare example of a singly oxygenated sulfenate, [FeIII(η2-SMe2O)(SMe2)N3(Pr,Pr)]+ (5), resembling both a proposed intermediate in the CDO catalytic cycle and the essential NHase Fe-S(O)Cys114 proposed to be intimately involved in nitrile hydrolysis. Comparison of the reactivity of 2 with that of a more electron-rich, crystallographically characterized derivative, [FeIIIS2Me2NMeN2amide(Pr,Pr)]- (8), shows that oxo atom donor reactivity correlates with the metal ion's ability to bind exogenous ligands. Density functional theory calculations suggest that the mechanism of S-oxygenation does not proceed via direct attack at the thiolate sulfurs; the average spin-density on the thiolate sulfurs is approximately the same for 2 and 8, and Mulliken charges on the sulfurs of 8 are roughly twice those of 2, implying that 8 should be more susceptible to sulfur oxidation. Carboxamide-ligated 8 is shown to be unreactive towards oxo atom donors, in contrast to imine-ligated 2. Azide (N3-) is shown to inhibit sulfur oxidation with 2, and a green intermediate is observed, which then slowly converts to sulfenate-ligated 5. This suggests that the mechanism of sulfur oxidation involves initial coordination of the oxo atom donor to the metal ion. Whether the green intermediate is an oxo atom donor adduct, Fe-O═I-Ph, or an Fe(V)═O remains to be determined.
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Affiliation(s)
- Gloria Villar-Acevedo
- The Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195-1700, United States
| | - Priscilla Lugo-Mas
- The Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195-1700, United States
| | - Maike N Blakely
- The Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195-1700, United States
| | - Julian A Rees
- The Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195-1700, United States
| | - Abbie S Ganas
- The Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195-1700, United States
| | - Erin M Hanada
- The Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195-1700, United States
| | - Werner Kaminsky
- The Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195-1700, United States
| | - Julie A Kovacs
- The Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195-1700, United States
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164
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Abstract
The great diversity and richness of transition metal chemistry, such as the features of an open d-shell, opened a way to numerous areas of scientific research and technological applications. Depending on the nature of the metal and its environment, there are often several energetically accessible spin states, and the progress in accurate theoretical treatment of this complicated phenomenon is presented in this Account. The spin state energetics of a transition metal complex can be predicted theoretically on the basis of density functional theory (DFT) or wave function based methodology, where DFT has advantages since it can be applied routinely to medium-to-large-sized molecules and spin-state consistent density functionals are now available. Additional factors such as the effect of the basis set, thermochemical contributions, solvation, relativity, and dispersion, have been investigated by many researchers, but challenges in unambiguous assignment of spin states still remain. The first DFT studies showed intrinsic spin-state preferences of hybrid functionals for high spin and early generalized gradient approximation functionals for low spin. Progress in the development of density functional approximations (DFAs) then led to a class of specially designed DFAs, such as OPBE, SSB-D, and S12g, and brought a very intriguing and fascinating observation that the spin states of transition metals and the SN2 barriers of organic molecules are somehow intimately linked. Among the many noteworthy results that emerged from the search for the appropriate description of the complicated spin state preferences in transition metals, we mainly focused on the examination of the connection between the spin state and the structures or coordination modes of the transition metal complexes. Changes in spin states normally lead only to changes in the metal-ligand bond lengths, but to the best of our knowledge, the dapsox ligand showed the first example of a transition-metal complex where a change in spin state leads also to changes in the coordination, switching between pentagonal-bipyramidal and capped-octahedron. Moreover, we have summarized the results of the thorough study that corrected the experimental assignment of the nature of the recently synthesized Sc3+ adduct of [FeIV(O)(TMC)]2+ (TMC = 1,4,8,11-tetramethylcyclam) and firmly established that the Sc3+-capped iron-oxygen complex corresponds to high-spin FeIII. Last, but not least, we have provided deeper insight and rationalization of the observation that unlike in metalloenzymes, where the FeIV-oxo is usually observed with high spin, biomimetic FeIV-oxo complexes typically have a intermediate spin state. Energy decomposition analyses on the trigonal-bypiramidal (TBP) and octahedral model systems with ammonia ligands have revealed that the interaction energy of the prepared metal ion in the intermediate spin state is much smaller for the TBP structure. This sheds light on the origin of the intermediate spin state of the biomimetic TBP FeIV-oxo complexes.
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Affiliation(s)
- Marcel Swart
- ICREA, Pg. Lluís Companys 23, 08010 Barcelona, Spain
- Institut de Química Computacional i Catàlisi (IQCC) & Dept. Química, Universitat de Girona, Campus Montilivi, 17071 Girona, Spain
| | - Maja Gruden
- Center
for Computational Chemistry and Bioinformatics, Faculty of Chemistry, University of Belgrade, Belgrade 11000, Serbia
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165
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Leto DF, Massie AA, Rice DB, Jackson TA. Spectroscopic and Computational Investigations of a Mononuclear Manganese(IV)-Oxo Complex Reveal Electronic Structure Contributions to Reactivity. J Am Chem Soc 2016; 138:15413-15424. [PMID: 27802057 DOI: 10.1021/jacs.6b08661] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The mononuclear Mn(IV)-oxo complex [MnIV(O)(N4py)]2+, where N4py is the pentadentate ligand N,N-bis(2-pyridylmethyl)-N-bis(2-pyridyl)methylamine, has been proposed to attack C-H bonds by an excited-state reactivity pattern [ Cho, K.-B.; Shaik, S.; Nam, W. J. Phys. Chem. Lett. 2012 , 3 , 2851 - 2856 (DOI: 10.1021/jz301241z )]. In this model, a 4E excited state is utilized to provide a lower-energy barrier for hydrogen-atom transfer. This proposal is intriguing, as it offers both a rationale for the relatively high hydrogen-atom-transfer reactivity of [MnIV(O)(N4py)]2+ and a guideline for creating more reactive complexes through ligand modification. Here we employ a combination of electronic absorption and variable-temperature magnetic circular dichroism (MCD) spectroscopy to experimentally evaluate this excited-state reactivity model. Using these spectroscopic methods, in conjunction with time-dependent density functional theory (TD-DFT) and complete-active space self-consistent-field calculations (CASSCF), we define the ligand-field and charge-transfer excited states of [MnIV(O)(N4py)]2+. Through a graphical analysis of the signs of the experimental C-term MCD signals, we unambiguously assign a low-energy MCD feature of [MnIV(O)(N4py)]2+ as the 4E excited state predicted to be involved in hydrogen-atom-transfer reactivity. The CASSCF calculations predict enhanced MnIII-oxyl character on the excited-state 4E surface, consistent with previous DFT calculations. Potential-energy surfaces, developed using the CASSCF methods, are used to determine how the energies and wave functions of the ground and excited states evolved as a function of Mn═O distance. The unique insights into ground- and excited-state electronic structure offered by these spectroscopic and computational studies are harmonized with a thermodynamic model of hydrogen-atom-transfer reactivity, which predicts a correlation between transition-state barriers and driving force.
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Affiliation(s)
- Domenick F Leto
- Department of Chemistry and Center for Environmentally Beneficial Catalysis, University of Kansas , Lawrence, Kansas 66045, United States
| | - Allyssa A Massie
- Department of Chemistry and Center for Environmentally Beneficial Catalysis, University of Kansas , Lawrence, Kansas 66045, United States
| | - Derek B Rice
- Department of Chemistry and Center for Environmentally Beneficial Catalysis, University of Kansas , Lawrence, Kansas 66045, United States
| | - Timothy A Jackson
- Department of Chemistry and Center for Environmentally Beneficial Catalysis, University of Kansas , Lawrence, Kansas 66045, United States
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166
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Proshlyakov DA, McCracken J, Hausinger RP. Spectroscopic analyses of 2-oxoglutarate-dependent oxygenases: TauD as a case study. J Biol Inorg Chem 2016; 22:367-379. [PMID: 27812832 DOI: 10.1007/s00775-016-1406-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 10/25/2016] [Indexed: 11/28/2022]
Abstract
A wide range of spectroscopic approaches have been used to interrogate the mononuclear iron metallocenter in 2-oxoglutarate (2OG)-dependent oxygenases. The results from these spectroscopic studies have provided valuable insights into the structural changes at the active site during substrate binding and catalysis, thus providing critical information that complements investigations of these enzymes by X-ray crystallography, biochemical, and computational approaches. This mini-review highlights taurine hydroxylase (taurine:2OG dioxygenase, TauD) as a case study to illustrate the wealth of knowledge that can be generated by applying a diverse array of spectroscopic investigations to a single enzyme. In particular, electronic absorption, circular dichroism, magnetic circular dichroism, conventional and pulse electron paramagnetic, Mössbauer, X-ray absorption, and resonance Raman methods have been exploited to uncover the properties of the metal site in TauD.
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Affiliation(s)
- Denis A Proshlyakov
- Department of Chemistry, Michigan State University, East Lansing, MI, 48824, USA
| | - John McCracken
- Department of Chemistry, Michigan State University, East Lansing, MI, 48824, USA
| | - Robert P Hausinger
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, 48824, USA. .,Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA.
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167
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Xiao DJ, Oktawiec J, Milner PJ, Long JR. Pore Environment Effects on Catalytic Cyclohexane Oxidation in Expanded Fe2(dobdc) Analogues. J Am Chem Soc 2016; 138:14371-14379. [DOI: 10.1021/jacs.6b08417] [Citation(s) in RCA: 116] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
| | | | | | - Jeffrey R. Long
- Materials
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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168
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Hill EA, Weitz AC, Onderko E, Romero-Rivera A, Guo Y, Swart M, Bominaar EL, Green MT, Hendrich MP, Lacy DC, Borovik AS. Reactivity of an Fe IV-Oxo Complex with Protons and Oxidants. J Am Chem Soc 2016; 138:13143-13146. [PMID: 27647293 PMCID: PMC5110122 DOI: 10.1021/jacs.6b07633] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
High-valent Fe-OH species are often invoked as key intermediates but have only been observed in Compound II of cytochrome P450s. To further address the properties of non-heme FeIV-OH complexes, we demonstrate the reversible protonation of a synthetic FeIV-oxo species containing a tris-urea tripodal ligand. The same protonated FeIV-oxo species can be prepared via oxidation, suggesting that a putative FeV-oxo species was initially generated. Computational, Mössbauer, XAS, and NRVS studies indicate that protonation of the FeIV-oxo complex most likely occurs on the tripodal ligand, which undergoes a structural change that results in the formation of a new intramolecular H-bond with the oxido ligand that aids in stabilizing the protonated adduct. We suggest that similar protonated high-valent Fe-oxo species may occur in the active sites of proteins. This finding further argues for caution when assigning unverified high-valent Fe-OH species to mechanisms.
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Affiliation(s)
- Ethan A. Hill
- Department of Chemistry, University of California-Irvine, 1102 Natural Sciences II, Irvine, CA 92697
| | - Andrew C. Weitz
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Elizabeth Onderko
- Department of Chemistry, Pennsylvania State University, University Park, PA 16802
| | - Adrian Romero-Rivera
- Institut de Química Computacional i Catàlisi & Dept. Química, Universitat de Girona, 17003, Spain
| | - Yisong Guo
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Marcel Swart
- Institut de Química Computacional i Catàlisi & Dept. Química, Universitat de Girona, 17003, Spain
- ICREA, Pg. Lluís Companys 23, 08010, Barcelona, Spain
| | - Emile L. Bominaar
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Michael T. Green
- Department of Chemistry, University of California-Irvine, 1102 Natural Sciences II, Irvine, CA 92697
- Department of Chemistry, Pennsylvania State University, University Park, PA 16802
| | | | - David C. Lacy
- Department of Chemistry, University of California-Irvine, 1102 Natural Sciences II, Irvine, CA 92697
| | - A. S. Borovik
- Department of Chemistry, University of California-Irvine, 1102 Natural Sciences II, Irvine, CA 92697
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169
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Lakk-Bogáth D, Csonka R, Speier G, Réglier M, Simaan AJ, Naubron JV, Giorgi M, Lázár K, Kaizer J. Formation, Characterization, and Reactivity of a Nonheme Oxoiron(IV) Complex Derived from the Chiral Pentadentate Ligand asN4Py. Inorg Chem 2016; 55:10090-10093. [PMID: 27690396 DOI: 10.1021/acs.inorgchem.6b01089] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The chiral pentadentate low-spin (S = 1) oxoiron(IV) complex [FeIV(O)(asN4Py)]2+ (2) was synthesized and spectroscopically characterized. Its formation kinetics, reactivity, and (enantio)selectivity in an oxygen-atom-transfer reaction was investigated in detail and compared to a similar pentadentate ligand-containing system.
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Affiliation(s)
- Dóra Lakk-Bogáth
- Department of Chemistry, University of Pannonia , 8201 Veszprém, Hungary
| | - Róbert Csonka
- Department of Chemistry, University of Pannonia , 8201 Veszprém, Hungary
| | - Gábor Speier
- Department of Chemistry, University of Pannonia , 8201 Veszprém, Hungary
| | - Marius Réglier
- Aix Marseille Université, CNRS, Centrale Marseille, iSm2 UMR 7313 , 13397 Marseille, France
| | - A Jalila Simaan
- Aix Marseille Université, CNRS, Centrale Marseille, iSm2 UMR 7313 , 13397 Marseille, France
| | - Jean-Valère Naubron
- Aix Marseille Université, CNRS, Centrale Marseille, Spectropole FR1739 , 13397 Marseille, France
| | - Michel Giorgi
- Aix Marseille Université, CNRS, Centrale Marseille, Spectropole FR1739 , 13397 Marseille, France
| | - Károly Lázár
- Research Centre for Energy, Hungarian Academy of Sciences , H-1525 Budapest, Hungary
| | - József Kaizer
- Department of Chemistry, University of Pannonia , 8201 Veszprém, Hungary
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170
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Nastri F, Chino M, Maglio O, Bhagi-Damodaran A, Lu Y, Lombardi A. Design and engineering of artificial oxygen-activating metalloenzymes. Chem Soc Rev 2016; 45:5020-54. [PMID: 27341693 PMCID: PMC5021598 DOI: 10.1039/c5cs00923e] [Citation(s) in RCA: 133] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Many efforts are being made in the design and engineering of metalloenzymes with catalytic properties fulfilling the needs of practical applications. Progress in this field has recently been accelerated by advances in computational, molecular and structural biology. This review article focuses on the recent examples of oxygen-activating metalloenzymes, developed through the strategies of de novo design, miniaturization processes and protein redesign. Considerable progress in these diverse design approaches has produced many metal-containing biocatalysts able to adopt the functions of native enzymes or even novel functions beyond those found in Nature.
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Affiliation(s)
- Flavia Nastri
- Department of Chemical Sciences, University of Naples “Federico II”, Via Cintia, 80126 Naples, Italy
| | - Marco Chino
- Department of Chemical Sciences, University of Naples “Federico II”, Via Cintia, 80126 Naples, Italy
| | - Ornella Maglio
- Department of Chemical Sciences, University of Naples “Federico II”, Via Cintia, 80126 Naples, Italy
- IBB, CNR, Via Mezzocannone 16, 80134 Naples, Italy
| | - Ambika Bhagi-Damodaran
- Department of Chemistry, University of Illinois at Urbana-Champaign, A322 CLSL, 600 South Mathews Avenue, Urbana, IL 61801
| | - Yi Lu
- Department of Chemistry, University of Illinois at Urbana-Champaign, A322 CLSL, 600 South Mathews Avenue, Urbana, IL 61801
| | - Angela Lombardi
- Department of Chemical Sciences, University of Naples “Federico II”, Via Cintia, 80126 Naples, Italy
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171
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Snyder BER, Vanelderen P, Bols ML, Hallaert SD, Böttger LH, Ungur L, Pierloot K, Schoonheydt RA, Sels BF, Solomon EI. The active site of low-temperature methane hydroxylation in iron-containing zeolites. Nature 2016; 536:317-21. [PMID: 27535535 DOI: 10.1038/nature19059] [Citation(s) in RCA: 228] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 06/13/2016] [Indexed: 12/21/2022]
Abstract
An efficient catalytic process for converting methane into methanol could have far-reaching economic implications. Iron-containing zeolites (microporous aluminosilicate minerals) are noteworthy in this regard, having an outstanding ability to hydroxylate methane rapidly at room temperature to form methanol. Reactivity occurs at an extra-lattice active site called α-Fe(ii), which is activated by nitrous oxide to form the reactive intermediate α-O; however, despite nearly three decades of research, the nature of the active site and the factors determining its exceptional reactivity are unclear. The main difficulty is that the reactive species-α-Fe(ii) and α-O-are challenging to probe spectroscopically: data from bulk techniques such as X-ray absorption spectroscopy and magnetic susceptibility are complicated by contributions from inactive 'spectator' iron. Here we show that a site-selective spectroscopic method regularly used in bioinorganic chemistry can overcome this problem. Magnetic circular dichroism reveals α-Fe(ii) to be a mononuclear, high-spin, square planar Fe(ii) site, while the reactive intermediate, α-O, is a mononuclear, high-spin Fe(iv)=O species, whose exceptional reactivity derives from a constrained coordination geometry enforced by the zeolite lattice. These findings illustrate the value of our approach to exploring active sites in heterogeneous systems. The results also suggest that using matrix constraints to activate metal sites for function-producing what is known in the context of metalloenzymes as an 'entatic' state-might be a useful way to tune the activity of heterogeneous catalysts.
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Affiliation(s)
- Benjamin E R Snyder
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
| | - Pieter Vanelderen
- Department of Chemistry, Stanford University, Stanford, California 94305, USA.,Department of Microbial and Molecular Systems, Centre for Surface Chemistry and Catalysis, KU Leuven - University of Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| | - Max L Bols
- Department of Microbial and Molecular Systems, Centre for Surface Chemistry and Catalysis, KU Leuven - University of Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| | - Simon D Hallaert
- Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| | - Lars H Böttger
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
| | - Liviu Ungur
- Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| | - Kristine Pierloot
- Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| | - Robert A Schoonheydt
- Department of Microbial and Molecular Systems, Centre for Surface Chemistry and Catalysis, KU Leuven - University of Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| | - Bert F Sels
- Department of Microbial and Molecular Systems, Centre for Surface Chemistry and Catalysis, KU Leuven - University of Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| | - Edward I Solomon
- Department of Chemistry, Stanford University, Stanford, California 94305, USA.,Photon Science, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
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172
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Sahu S, Goldberg DP. Activation of Dioxygen by Iron and Manganese Complexes: A Heme and Nonheme Perspective. J Am Chem Soc 2016; 138:11410-28. [PMID: 27576170 DOI: 10.1021/jacs.6b05251] [Citation(s) in RCA: 229] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The rational design of well-defined, first-row transition metal complexes that can activate dioxygen has been a challenging goal for the synthetic inorganic chemist. The activation of O2 is important in part because of its central role in the functioning of metalloenzymes, which utilize O2 to perform a number of challenging reactions including the highly selective oxidation of various substrates. There is also great interest in utilizing O2, an abundant and environmentally benign oxidant, in synthetic catalytic oxidation systems. This Perspective brings together recent examples of biomimetic Fe and Mn complexes that can activate O2 in heme or nonheme-type ligand environments. The use of oxidants such as hypervalent iodine (e.g., ArIO), peracids (e.g., m-CPBA), peroxides (e.g., H2O2) or even superoxide is a popular choice for accessing well-characterized metal-superoxo, metal-peroxo, or metal-oxo species, but the instances of biomimetic Fe/Mn complexes that react with dioxygen to yield such observable metal-oxygen species are surprisingly few. This Perspective focuses on mononuclear Fe and Mn complexes that exhibit reactivity with O2 and lead to spectroscopically observable metal-oxygen species, and/or oxidize biologically relevant substrates. Analysis of these examples reveals that solvent, spin state, redox potential, external co-reductants, and ligand architecture can all play important roles in the O2 activation process.
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Affiliation(s)
- Sumit Sahu
- Department of Chemistry, The Johns Hopkins University , Baltimore, Maryland 21218, United States
| | - David P Goldberg
- Department of Chemistry, The Johns Hopkins University , Baltimore, Maryland 21218, United States
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173
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Kim S, Cho KB, Lee YM, Chen J, Fukuzumi S, Nam W. Factors Controlling the Chemoselectivity in the Oxidation of Olefins by Nonheme Manganese(IV)-Oxo Complexes. J Am Chem Soc 2016; 138:10654-63. [PMID: 27462828 DOI: 10.1021/jacs.6b06252] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
We report the oxidation of cyclic olefins, such as cyclohexene, cyclohexene-d10, and cyclooctene, by mononuclear nonheme manganese(IV)-oxo (Mn(IV)O) and triflic acid (HOTf)-bound Mn(IV)O complexes. In the oxidation of cyclohexene, the Mn(IV)O complexes prefer the C-H bond activation to the C═C double bond epoxidation, whereas the C═C double bond epoxidation becomes a preferred reaction pathway in the cyclohexene oxidation by HOTf-bound Mn(IV)O complexes. In contrast, the oxidation of cyclohexene-d10 and cyclooctene by the Mn(IV)O complexes occurs predominantly via the C═C double bond epoxidation. This conclusion is drawn from the product analysis and kinetic studies of the olefin oxidation reactions, such as the epoxide versus allylic oxidation products, the formation of Mn(II) versus Mn(III) products, and the kinetic analyses. Overall, the experimental results suggest that the energy barrier of the C═C double bond epoxidation is very close to that of the allylic C-H bond activation in the oxidation of cyclic olefins by high-valent metal-oxo complexes. Thus, the preference of the reaction pathways is subject to changes upon small manipulation of the reaction environments, such as the supporting ligands and metal ions in metal-oxo species, the presence of HOTf (i.e., HOTf-bound Mn(IV)O species), and the allylic C-H(D) bond dissociation energies of olefins. This is confirmed by DFT calculations in the oxidation of cyclohexene and cyclooctene, which show multiple pathways with similar rate-limiting energy barriers and depending on the allylic C-H bond dissociation energies. In addition, the possibility of excited state reactivity in the current system is confirmed for epoxidation reactions.
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Affiliation(s)
- Surin Kim
- Department of Chemistry and Nano Science, Ewha Womans University , Seoul 03760, Korea
| | - Kyung-Bin Cho
- Department of Chemistry and Nano Science, Ewha Womans University , Seoul 03760, Korea
| | - Yong-Min Lee
- Department of Chemistry and Nano Science, Ewha Womans University , Seoul 03760, Korea
| | - Junying Chen
- Department of Chemistry and Nano Science, Ewha Womans University , Seoul 03760, Korea
| | - Shunichi Fukuzumi
- Department of Chemistry and Nano Science, Ewha Womans University , Seoul 03760, Korea
| | - Wonwoo Nam
- Department of Chemistry and Nano Science, Ewha Womans University , Seoul 03760, Korea
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174
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Comba P, Fukuzumi S, Koke C, Martin B, Löhr AM, Straub J. A Bispidine Iron(IV)-Oxo Complex in the Entatic State. Angew Chem Int Ed Engl 2016; 55:11129-33. [PMID: 27466945 DOI: 10.1002/anie.201605099] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 06/30/2016] [Indexed: 11/10/2022]
Abstract
For a series of Fe(IV) =O complexes with tetra- and pentadentate bispidine ligands, the correlation of their redox potentials with reactivity, involving a variety of substrates for alkane hydroxylation (HAT), alkene epoxidation, and phosphine and thioether oxidation (OAT) are reported. The redox potentials span approximately 350 mV and the reaction rates over 8 orders of magnitude. From the experimental data and in comparison with published studies it emerges that electron transfer and the driving force are of major importance, and this is also supported by the DFT-based computational analysis. The striking difference of reactivity of two isomeric systems with pentadentate bispidines is found to be due to a destabilization of the S=1 ground state of one of the ferryl isomers, and this is supported by the experimentally determined redox potentials and published stability constants with a series of first-row transition metal ions with these two isomeric ligands.
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Affiliation(s)
- Peter Comba
- Universität Heidelberg, Anorganisch-Chemisches Institut und Interdisziplinäres Zentrum für Wissenschaftliches Rechnen (IWR), INF 270, 69120, Heidelberg, Germany.
| | - Shunichi Fukuzumi
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 120-750, Korea. .,Faculty of Science and Engineering, Meijo University, Nagoya, Aichi, 468-8502, Japan.
| | - Carsten Koke
- Universität Heidelberg, Anorganisch-Chemisches Institut und Interdisziplinäres Zentrum für Wissenschaftliches Rechnen (IWR), INF 270, 69120, Heidelberg, Germany
| | - Bodo Martin
- Universität Heidelberg, Anorganisch-Chemisches Institut und Interdisziplinäres Zentrum für Wissenschaftliches Rechnen (IWR), INF 270, 69120, Heidelberg, Germany
| | - Anna-Maria Löhr
- Universität Heidelberg, Anorganisch-Chemisches Institut und Interdisziplinäres Zentrum für Wissenschaftliches Rechnen (IWR), INF 270, 69120, Heidelberg, Germany
| | - Johannes Straub
- Universität Heidelberg, Anorganisch-Chemisches Institut und Interdisziplinäres Zentrum für Wissenschaftliches Rechnen (IWR), INF 270, 69120, Heidelberg, Germany
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175
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Comba P, Fukuzumi S, Koke C, Martin B, Löhr AM, Straub J. A Bispidine Iron(IV)-Oxo Complex in the Entatic State. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201605099] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Peter Comba
- Universität Heidelberg; Anorganisch-Chemisches Institut und Interdisziplinäres Zentrum für Wissenschaftliches Rechnen (IWR), INF 270; 69120 Heidelberg Germany
| | - Shunichi Fukuzumi
- Department of Chemistry and Nano Science; Ewha Womans University; Seoul 120-750 Korea
- Faculty of Science and Engineering; Meijo University; Nagoya Aichi 468-8502 Japan
| | - Carsten Koke
- Universität Heidelberg; Anorganisch-Chemisches Institut und Interdisziplinäres Zentrum für Wissenschaftliches Rechnen (IWR), INF 270; 69120 Heidelberg Germany
| | - Bodo Martin
- Universität Heidelberg; Anorganisch-Chemisches Institut und Interdisziplinäres Zentrum für Wissenschaftliches Rechnen (IWR), INF 270; 69120 Heidelberg Germany
| | - Anna-Maria Löhr
- Universität Heidelberg; Anorganisch-Chemisches Institut und Interdisziplinäres Zentrum für Wissenschaftliches Rechnen (IWR), INF 270; 69120 Heidelberg Germany
| | - Johannes Straub
- Universität Heidelberg; Anorganisch-Chemisches Institut und Interdisziplinäres Zentrum für Wissenschaftliches Rechnen (IWR), INF 270; 69120 Heidelberg Germany
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176
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Wang B, Lu J, Dubey KD, Dong G, Lai W, Shaik S. How do Enzymes Utilize Reactive OH Radicals? Lessons from Nonheme HppE and Fenton Systems. J Am Chem Soc 2016; 138:8489-96. [PMID: 27309496 DOI: 10.1021/jacs.6b03555] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The iron(IV)-oxo (ferryl) intermediate has been amply established as the principal oxidant in nonheme enzymes and the key player in C-H bond activations and functionalizations. In contrast to this status, our present QM/MM calculations of the mechanism of fosfomycin biosynthesis (a broad range antibiotic) by the nonheme HppE enzyme rule out the iron(IV)-oxo as the reactive species in the hydrogen abstraction (H-abstraction) step of the pro-R hydrogen from the (S)-2-hydroxypropylphosphonic substrate. Moreover, the study reveals that the ferryl species is bypassed in HppE, while the actual oxidant is an HO(•) radical hydrogen-bonded to a ferric-hydroxo complex, resulting via the homolytic dissociation of the hydrogen peroxide complex, Fe(II)-H2O2. The computed energy barrier of this pathway is 12.0 kcal/mol, in fair agreement with the experimental datum of 9.8 kcal/mol. An alternative mechanism involves the iron-complexed hydroxyl radical (Fe(III)-(HO(•))) that is obtained by protonation of the iron(IV)-oxo group via the O-H group of the substrate. The barrier for this pathway, 23.0 kcal/mol, is higher than the one in the first mechanism. In both mechanisms, the HO(•) radical is highly selective; its H-abstraction leading to the final cis-fosfomycin product. It appears that HppE is prone to usage of HO(•) radicals for C-H bond activation, because the ferryl oxidant requires a specific H-abstraction trajectory (∠FeOH ∼ 180°) that cannot be met for intramolecular H-abstraction. Thus, this work broadens the landscape of nonheme iron enzymes and makes a connection to Fenton chemistry, with implications on new potential biocatalysts that may harness hydroxyl radicals for C-H bond functionalizations.
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Affiliation(s)
- Binju Wang
- Institute of Chemistry and The Lise Meitner-Minerva Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem , 91904 Jerusalem, Israel
| | - Jiarui Lu
- Department of Chemistry, Renmin University of China , Beijing 100872, China
| | - Kshatresh Dutta Dubey
- Institute of Chemistry and The Lise Meitner-Minerva Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem , 91904 Jerusalem, Israel
| | - Geng Dong
- Department of Chemistry, Renmin University of China , Beijing 100872, China
| | - Wenzhen Lai
- Department of Chemistry, Renmin University of China , Beijing 100872, China
| | - Sason Shaik
- Institute of Chemistry and The Lise Meitner-Minerva Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem , 91904 Jerusalem, Israel
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177
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Casadevall C, Codolà Z, Costas M, Lloret-Fillol J. Spectroscopic, Electrochemical and Computational Characterisation of Ru Species Involved in Catalytic Water Oxidation: Evidence for a [Ru(V) (O)(Py2 (Me) tacn)] Intermediate. Chemistry 2016; 22:10111-26. [PMID: 27324949 DOI: 10.1002/chem.201600584] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2016] [Indexed: 01/09/2023]
Abstract
A new family of ruthenium complexes based on the N-pentadentate ligand Py2 (Me) tacn (N-methyl-N',N''-bis(2-picolyl)-1,4,7-triazacyclononane) has been synthesised and its catalytic activity has been studied in the water-oxidation (WO) reaction. We have used chemical oxidants (ceric ammonium nitrate and NaIO4 ) to generate the WO intermediates [Ru(II) (OH2 )(Py2 (Me) tacn)](2+) , [Ru(III) (OH2 )(Py2 (Me) tacn)](3+) , [Ru(III) (OH)(Py2 (Me) tacn)](2+) and [Ru(IV) (O)(Py2 (Me) tacn)](2+) , which have been characterised spectroscopically. Their relative redox and pH stability in water has been studied by using UV/Vis and NMR spectroscopies, HRMS and spectroelectrochemistry. [Ru(IV) (O)(Py2 (Me) tacn)](2+) has a long half-life (>48 h) in water. The catalytic cycle of WO has been elucidated by using kinetic, spectroscopic, (18) O-labelling and theoretical studies, and the conclusion is that the rate-determining step is a single-site water nucleophilic attack on a metal-oxo species. Moreover, [Ru(IV) (O)(Py2 (Me) tacn)](2+) is proposed to be the resting state under catalytic conditions. By monitoring Ce(IV) consumption, we found that the O2 evolution rate is redox-controlled and independent of the initial concentration of Ce(IV) . Based on these facts, we propose herein that [Ru(IV) (O)(Py2 (Me) tacn)](2+) is oxidised to [Ru(V) (O)(Py2 (Me) tacn)](2+) prior to attack by a water molecule to give [Ru(III) (OOH)(Py2 (Me) tacn)](2+) . Finally, it is shown that the difference in WO reactivity between the homologous iron and ruthenium [M(OH2 )(Py2 (Me) tacn)](2+) (M=Ru, Fe) complexes is due to the difference in the redox stability of the key M(V) (O) intermediate. These results contribute to a better understanding of the WO mechanism and the differences between iron and ruthenium complexes in WO reactions.
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Affiliation(s)
- Carla Casadevall
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Avinguda Països Catalans 16, 43007, Tarragona, Spain
| | - Zoel Codolà
- Institut de Química Computacional i Catàlisi (IQCC) and, Departament de Química, Universitat de Girona Campus Montilivi, 17071, Girona, Spain
| | - Miquel Costas
- Institut de Química Computacional i Catàlisi (IQCC) and, Departament de Química, Universitat de Girona Campus Montilivi, 17071, Girona, Spain
| | - Julio Lloret-Fillol
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Avinguda Països Catalans 16, 43007, Tarragona, Spain.
- Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010, Barcelona, Spain.
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178
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Bae SH, Seo MS, Lee YM, Cho KB, Kim WS, Nam W. Mononuclear Nonheme High-Spin (S
=2) versus Intermediate-Spin (S
=1) Iron(IV)-Oxo Complexes in Oxidation Reactions. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201603978] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Seong Hee Bae
- Department of Chemistry and Nano Science; Ewha Womans University; Seoul 03760 Korea
| | - Mi Sook Seo
- Department of Chemistry and Nano Science; Ewha Womans University; Seoul 03760 Korea
| | - Yong-Min Lee
- Department of Chemistry and Nano Science; Ewha Womans University; Seoul 03760 Korea
| | - Kyung-Bin Cho
- Department of Chemistry and Nano Science; Ewha Womans University; Seoul 03760 Korea
| | - Won-Suk Kim
- Department of Chemistry and Nano Science; Ewha Womans University; Seoul 03760 Korea
| | - Wonwoo Nam
- Department of Chemistry and Nano Science; Ewha Womans University; Seoul 03760 Korea
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179
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Bae SH, Seo MS, Lee YM, Cho KB, Kim WS, Nam W. Mononuclear Nonheme High-Spin (S=2) versus Intermediate-Spin (S=1) Iron(IV)-Oxo Complexes in Oxidation Reactions. Angew Chem Int Ed Engl 2016; 55:8027-31. [PMID: 27273456 DOI: 10.1002/anie.201603978] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Indexed: 12/18/2022]
Abstract
Mononuclear nonheme high-spin (S=2) iron(IV)-oxo species have been identified as the key intermediates responsible for the C-H bond activation of organic substrates in nonheme iron enzymatic reactions. Herein we report that the C-H bond activation of hydrocarbons by a synthetic mononuclear nonheme high-spin (S=2) iron(IV)-oxo complex occurs through an oxygen non-rebound mechanism, as previously demonstrated in the C-H bond activation by nonheme intermediate (S=1) iron(IV)-oxo complexes. We also report that C-H bond activation is preferred over C=C epoxidation in the oxidation of cyclohexene by the nonheme high-spin (HS) and intermediate-spin (IS) iron(IV)-oxo complexes, whereas the C=C double bond epoxidation becomes a preferred pathway in the oxidation of deuterated cyclohexene by the nonheme HS and IS iron(IV)-oxo complexes. In the epoxidation of styrene derivatives, the HS and IS iron(IV) oxo complexes are found to have similar electrophilic characters.
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Affiliation(s)
- Seong Hee Bae
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 03760, Korea
| | - Mi Sook Seo
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 03760, Korea
| | - Yong-Min Lee
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 03760, Korea
| | - Kyung-Bin Cho
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 03760, Korea
| | - Won-Suk Kim
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 03760, Korea
| | - Wonwoo Nam
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 03760, Korea.
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180
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Cho KB, Nam W. A theoretical study into a trans-dioxo Mn(V) porphyrin complex that does not follow the oxygen rebound mechanism in C-H bond activation reactions. Chem Commun (Camb) 2016; 52:904-7. [PMID: 26576748 DOI: 10.1039/c5cc08734a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Previous experimental results revealed that the C-H bond activation reaction by a synthetic trans-dioxo Mn(V) porphyrin complex, [(TF4TMAP)OMn(V)O](3+), does not occur via the well-known oxygen rebound mechanism, which has been well demonstrated in Fe(IV)O porphyrin π-cation radical reactions. In the present study, theoretical calculations offer an explanation through the energetics involved in the C-H bond activation reaction, where a multi-spin state scenario cannot be excluded.
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Affiliation(s)
- Kyung-Bin Cho
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea.
| | - Wonwoo Nam
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea.
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181
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The Effect of Ligand Design on Metal Ion Spin State—Lessons from Spin Crossover Complexes. CRYSTALS 2016. [DOI: 10.3390/cryst6050058] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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182
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Shen K, Ben-David H, Laskavy A, Leitus G, Simon LJW, Neumann R. Electronic Control of RuII Complexes with Proximal Oxophilic Phenylselenium Tethers: Synthesis, Characterization, and Activation of Molecular Oxygen. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201600123] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Kaiji Shen
- Department of Organic Chemistry; Weizmann Institute of Science; 76100 Rehovot Israel
| | - Haviv Ben-David
- Department of Organic Chemistry; Weizmann Institute of Science; 76100 Rehovot Israel
| | - Alexander Laskavy
- Department of Organic Chemistry; Weizmann Institute of Science; 76100 Rehovot Israel
| | - Gregory Leitus
- Department of Chemical Research Support; Weizmann Institute of Science; 76100 Rehovot Israel
| | - Linda J. W. Simon
- Department of Chemical Research Support; Weizmann Institute of Science; 76100 Rehovot Israel
| | - Ronny Neumann
- Department of Organic Chemistry; Weizmann Institute of Science; 76100 Rehovot Israel
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183
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Afanasiev P, Sorokin AB. μ-Nitrido Diiron Macrocyclic Platform: Particular Structure for Particular Catalysis. Acc Chem Res 2016; 49:583-93. [PMID: 26967682 DOI: 10.1021/acs.accounts.5b00458] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The ultimate objective of bioinspired catalysis is the development of efficient and clean chemical processes. Cytochrome P450 and soluble methane monooxygenase enzymes efficiently catalyze many challenging reactions. Extensive research has been performed to mimic their exciting chemistry, aiming to create efficient chemical catalysts for functionalization of strong C-H bonds. Two current biomimetic approaches are based on (i) mononuclear metal porphyrin-like complexes and (ii) iron and diiron non-heme complexes. However, biomimetic catalysts capable of oxidizing CH4 are still to be created. In the search for powerful oxidizing catalysts, we have recently proposed a new bioinspired strategy using N-bridged diiron phthalocyanine and porphyrin complexes. This platform is particularly suitable for stabilization of Fe(IV)Fe(IV) complexes and can be useful to generate high-valent oxidizing active species. Indeed, the possibility of charge delocalization on two iron centers, two macrocyclic ligands, and the nitrogen bridge makes possible the activation of H2O2 and peracids. The ultrahigh-valent diiron-oxo species (L)Fe(IV)-N-Fe(IV)(L(+•))═O (L = porphyrin or phthalocyanine) have been prepared at low temperatures and characterized by cryospray MS, UV-vis, EPR, and Mössbauer techniques. The highly electrophilic (L)Fe(IV)-N-Fe(IV)(L(+•))═O species exhibit remarkable reactivity. In this Account, we describe the catalytic applications of μ-nitrido diiron complexes in the oxidation of methane and benzene, in the transformation of aromatic C-F bonds under oxidative conditions, in oxidative dechlorination, and in the formation of C-C bonds. Importantly, all of these reactions can be performed under mild and clean conditions with high conversions and turnover numbers. μ-Nitrido diiron species retain their binuclear structure during catalysis and show the same mechanistic features (e.g., (18)O labeling, formation of benzene epoxide, and NIH shift in aromatic oxidation) as the enzymes operating via high-valent iron-oxo species. μ-Nitrido diiron complexes can react with perfluorinated aromatics under oxidative conditions, while the strongest oxidizing enzymes cannot. Advanced spectroscopic, labeling, and reactivity studies have confirmed the involvement of high-valent diiron-oxo species in these catalytic reactions. Computational studies have shed light on the origin of the remarkable catalytic properties, distinguishing the Fe-N-Fe scaffold from Fe-C-Fe and Fe-O-Fe analogues. X-ray absorption and emission spectroscopies assisted with DFT calculations allow deeper insight into the electronic structure of these particular complexes. Besides the novel chemistry involved, iron phthalocyanines are cheap and readily available in bulk quantities, suggesting high application potential. A variety of macrocyclic ligands can be used in combination with different transition metals to accommodate M-N-M platform and to tune their electronic and catalytic properties. The structural simplicity and flexibility of μ-nitrido dimers make them promising catalysts for many challenging reactions.
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Affiliation(s)
- Pavel Afanasiev
- Institut de Recherches sur
la Catalyse et l’Environnement de Lyon IRCELYON, UMR 5256, CNRS - Université Lyon 1, 2 avenue A. Einstein, 69626 Villeurbanne cedex, France
| | - Alexander B. Sorokin
- Institut de Recherches sur
la Catalyse et l’Environnement de Lyon IRCELYON, UMR 5256, CNRS - Université Lyon 1, 2 avenue A. Einstein, 69626 Villeurbanne cedex, France
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184
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Padamati SK, Draksharapu A, Unjaroen D, Browne WR. Conflicting Role of Water in the Activation of H2O2 and the Formation and Reactivity of Non-Heme FeIII–OOH and FeIII–O–FeIII Complexes at Room Temperature. Inorg Chem 2016; 55:4211-22. [DOI: 10.1021/acs.inorgchem.5b02976] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Sandeep K. Padamati
- Molecular
Inorganic Chemistry, Stratingh Institute for Chemistry, Faculty of
Mathematics and Natural Sciences, University of Groningen, Nijenborgh
4, 9747AG, Groningen, The Netherlands
| | - Apparao Draksharapu
- Molecular
Inorganic Chemistry, Stratingh Institute for Chemistry, Faculty of
Mathematics and Natural Sciences, University of Groningen, Nijenborgh
4, 9747AG, Groningen, The Netherlands
| | - Duenpen Unjaroen
- Molecular
Inorganic Chemistry, Stratingh Institute for Chemistry, Faculty of
Mathematics and Natural Sciences, University of Groningen, Nijenborgh
4, 9747AG, Groningen, The Netherlands
| | - Wesley R. Browne
- Molecular
Inorganic Chemistry, Stratingh Institute for Chemistry, Faculty of
Mathematics and Natural Sciences, University of Groningen, Nijenborgh
4, 9747AG, Groningen, The Netherlands
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185
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Sekino M, Furutachi H, Tasaki K, Ishikawa T, Mori S, Fujinami S, Akine S, Sakata Y, Nomura T, Ogura T, Kitagawa T, Suzuki M. New mechanistic insight into intramolecular arene hydroxylation initiated by (μ-1,2-peroxo)diiron(III) complexes with dinucleating ligands. Dalton Trans 2016; 45:469-73. [PMID: 26646073 DOI: 10.1039/c5dt04088d] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
(μ-1,2-Peroxo)diiron(iii) complexes (-R) with dinucleating ligands (R-L) generated from the reaction of bis(μ-hydroxo)diiron(ii) complexes [Fe2(R-L)(OH)2](2+) (-R) with dioxygen in acetone at -20 °C provide a diiron-centred electrophilic oxidant, presumably diiron(iv)-oxo species, which is involved in aromatic ligand hydroxylation.
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Affiliation(s)
- Mio Sekino
- Department of Chemistry, Division of Material Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
| | - Hideki Furutachi
- Department of Chemistry, Division of Material Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
| | - Kyosuke Tasaki
- Department of Chemistry, Division of Material Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
| | - Takanao Ishikawa
- Department of Chemistry, Division of Material Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
| | - Shigeki Mori
- Department of Chemistry, Division of Material Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
| | - Shuhei Fujinami
- Department of Chemistry, Division of Material Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
| | - Shigehisa Akine
- Department of Chemistry, Division of Material Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
| | - Yoko Sakata
- Department of Chemistry, Division of Material Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
| | - Takashi Nomura
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, Ako-gun, Hyogo 678-1297, Japan
| | - Takashi Ogura
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, Ako-gun, Hyogo 678-1297, Japan
| | - Teizo Kitagawa
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, Ako-gun, Hyogo 678-1297, Japan
| | - Masatatsu Suzuki
- Department of Chemistry and Biochemistry, Graduate Engineering, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
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186
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Bucinsky L, Rohde GT, Que L, Ozarowski A, Krzystek J, Breza M, Telser J. HFEPR and Computational Studies on the Electronic Structure of a High-Spin Oxidoiron(IV) Complex in Solution. Inorg Chem 2016; 55:3933-45. [PMID: 27031000 DOI: 10.1021/acs.inorgchem.6b00169] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Nonheme iron enzymes perform diverse and important functions in biochemistry. The active form of these enzymes comprises the ferryl, oxidoiron(IV), [FeO](2+) unit. In enzymes, this unit is in the high-spin, quintet, S = 2, ground state, while many synthetic model compounds exist in the spin triplet, S = 1, ground state. Recently, however, Que and co-workers reported an oxidoiron(IV) complex with a quintet ground state, [FeO(TMG3tren)](OTf)2, where TMG3tren = 1,1,1-tris{2-[N2-(1,1,3,3-tetramethylguanidino)]ethyl}amine and OTf = CF3SO3(-). The trigonal geometry imposed by this ligand, as opposed to the tetragonal geometry of earlier model complexes, favors the high-spin ground state. Although [FeO(TMG3tren)](2+) has been earlier probed by magnetic circular dichroism (MCD) and Mössbauer spectroscopies, the technique of high-frequency and -field electron paramagnetic resonance (HFEPR) is superior for describing the electronic structure of the iron(IV) center because of its ability to establish directly the spin-Hamiltonian parameters of high-spin metal centers with high precision. Herein we describe HFEPR studies on [FeO(TMG3tren)](OTf)2 generated in situ and confirm the S = 2 ground state with the following parameters: D = +4.940(5) cm(-1), E = 0.000(5), B4(0) = -14(1) × 10(-4) cm(-1), g⊥ = 2.006(2), and g∥ = 2.03(2). Extraction of a fourth-order spin-Hamiltonian parameter is unusual for HFEPR and impossible by other techniques. These experimental results are combined with state-of-the-art computational studies along with previous structural and spectroscopic results to provide a complete picture of the electronic structure of this biomimetic complex. Specifically, the calculations reproduce well the spin-Hamiltonian parameters of the complex, provide a satisfying geometrical picture of the S = 2 oxidoiron(IV) moiety, and demonstrate that the TMG3tren is an "innocent" ligand.
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Affiliation(s)
- Lukas Bucinsky
- Institute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology, Slovak University of Technology , Radlinského 9, SK-81237 Bratislava, Slovakia
| | - Gregory T Rohde
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Lawrence Que
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Andrew Ozarowski
- National High Magnetic Field Laboratory, Florida State University , Tallahassee, Florida 32310, United States
| | - J Krzystek
- National High Magnetic Field Laboratory, Florida State University , Tallahassee, Florida 32310, United States
| | - Martin Breza
- Institute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology, Slovak University of Technology , Radlinského 9, SK-81237 Bratislava, Slovakia
| | - Joshua Telser
- Department of Biological, Chemical and Physical Sciences, Roosevelt University , Chicago, Illinois 60605, United States
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187
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Sun Y, Tang H, Chen K, Hu L, Yao J, Shaik S, Chen H. Two-State Reactivity in Low-Valent Iron-Mediated C–H Activation and the Implications for Other First-Row Transition Metals. J Am Chem Soc 2016; 138:3715-30. [DOI: 10.1021/jacs.5b12150] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Yihua Sun
- Beijing
National Laboratory for Molecular Sciences (BNLMS), Key Laboratory
of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Hao Tang
- Beijing
National Laboratory for Molecular Sciences (BNLMS), Key Laboratory
of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Kejuan Chen
- Beijing
National Laboratory for Molecular Sciences (BNLMS), Key Laboratory
of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Lianrui Hu
- Beijing
National Laboratory for Molecular Sciences (BNLMS), Key Laboratory
of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Jiannian Yao
- Beijing
National Laboratory for Molecular Sciences (BNLMS), Key Laboratory
of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Sason Shaik
- Institute
of Chemistry and the Lise Meitner-Minerva Center for Computational
Quantum Chemistry, The Hebrew University of Jerusalem, 91904 Jerusalem, Israel
| | - Hui Chen
- Beijing
National Laboratory for Molecular Sciences (BNLMS), Key Laboratory
of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
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188
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Puri M, Biswas AN, Fan R, Guo Y, Que L. Modeling Non-Heme Iron Halogenases: High-Spin Oxoiron(IV)-Halide Complexes That Halogenate C-H Bonds. J Am Chem Soc 2016; 138:2484-7. [PMID: 26875530 DOI: 10.1021/jacs.5b11511] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The non-heme iron halogenases CytC3 and SyrB2 catalyze C-H bond halogenation in the biosynthesis of some natural products via S = 2 oxoiron(IV)-halide intermediates. These oxidants abstract a hydrogen atom from a substrate C-H bond to generate an alkyl radical that reacts with the bound halide to form a C-X bond chemoselectively. The origin of this selectivity has been explored in biological systems but has not yet been investigated with synthetic models. Here we report the characterization of S = 2 [Fe(IV)(O)(TQA)(Cl/Br)](+) (TQA = tris(quinolyl-2-methyl)amine) complexes that can preferentially halogenate cyclohexane. These are the first synthetic oxoiron(IV)-halide complexes that serve as spectroscopic and functional models for the halogenase intermediates. Interestingly, the nascent substrate radicals generated by these synthetic complexes are not as short-lived as those obtained from heme-based oxidants and can be intercepted by O2 to prevent halogenation, supporting an emerging notion that rapid rebound may not necessarily occur in non-heme oxoiron(IV) oxidations.
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Affiliation(s)
- Mayank Puri
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Achintesh N Biswas
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Ruixi Fan
- Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Yisong Guo
- Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Lawrence Que
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota , Minneapolis, Minnesota 55455, United States
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189
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Andris E, Jašík J, Gómez L, Costas M, Roithová J. Spectroscopic Characterization and Reactivity of Triplet and Quintet Iron(IV) Oxo Complexes in the Gas Phase. Angew Chem Int Ed Engl 2016; 55:3637-41. [PMID: 26878833 PMCID: PMC4778411 DOI: 10.1002/anie.201511374] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Indexed: 11/23/2022]
Abstract
Closely structurally related triplet and quintet iron(IV) oxo complexes with a tetradentate aminopyridine ligand were generated in the gas phase, spectroscopically characterized, and their reactivities in hydrogen‐transfer and oxygen‐transfer reactions were compared. The spin states were unambiguously assigned based on helium tagging infrared photodissociation (IRPD) spectra of the mass‐selected iron complexes. It is shown that the stretching vibrations of the nitrate counterion can be used as a spectral marker of the central iron spin state.
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Affiliation(s)
- Erik Andris
- Department of Organic Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030/8, 12843, Prague 2, Czech Republic
| | - Juraj Jašík
- Department of Organic Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030/8, 12843, Prague 2, Czech Republic
| | - Laura Gómez
- Departament de Quimica and Institute of Computational Chemistry and Catalysis (IQCC), University of Girona, Campus Montilivi, Girona, 17071, Spain.,Serveis Tècnics de Recerca (STR), Universitat de Girona, Parc Científic i Tecnològic, 17003, Girona, Spain
| | - Miquel Costas
- Departament de Quimica and Institute of Computational Chemistry and Catalysis (IQCC), University of Girona, Campus Montilivi, Girona, 17071, Spain.
| | - Jana Roithová
- Department of Organic Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030/8, 12843, Prague 2, Czech Republic.
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190
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Andris E, Jašík J, Gómez L, Costas M, Roithová J. Spectroscopic Characterization and Reactivity of Triplet and Quintet Iron(IV) Oxo Complexes in the Gas Phase. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201511374] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Erik Andris
- Department of Organic Chemistry; Faculty of Science; Charles University in Prague; Hlavova 2030/8 12843 Prague 2 Czech Republic
| | - Juraj Jašík
- Department of Organic Chemistry; Faculty of Science; Charles University in Prague; Hlavova 2030/8 12843 Prague 2 Czech Republic
| | - Laura Gómez
- Departament de Quimica and Institute of Computational Chemistry and Catalysis (IQCC); University of Girona; Campus Montilivi Girona 17071 Spain
- Serveis Tècnics de Recerca (STR); Universitat de Girona; Parc Científic i Tecnològic 17003 Girona Spain
| | - Miquel Costas
- Departament de Quimica and Institute of Computational Chemistry and Catalysis (IQCC); University of Girona; Campus Montilivi Girona 17071 Spain
| | - Jana Roithová
- Department of Organic Chemistry; Faculty of Science; Charles University in Prague; Hlavova 2030/8 12843 Prague 2 Czech Republic
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191
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de Ruiter G, Thompson NB, Takase MK, Agapie T. Intramolecular C-H and C-F Bond Oxygenation Mediated by a Putative Terminal Oxo Species in Tetranuclear Iron Complexes. J Am Chem Soc 2016; 138:1486-9. [PMID: 26760217 PMCID: PMC4871154 DOI: 10.1021/jacs.5b12214] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Herein we report the intramolecular arene C-H and C-F bond oxygenation by tetranuclear iron complexes. Treatment of [LFe3(PhPz)3OFe][OTf]2 (1) or its fluorinated analog [LFe3(F2ArPz)3OFe][OTf]2 (5) with iodosobenzene results in the regioselective hydroxylation of a bridging pyrazolate ligand, converting a C-H or C-F bond into a C-O bond. The observed reactivity suggests the formation of terminal and reactive Fe-oxo intermediates. With the possibility of intramolecular electron transfer within clusters in 1 and 5, different reaction pathways (Fe(IV)-oxo vs Fe(III)-oxo) might be responsible for the observed arene hydroxylation.
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Affiliation(s)
- Graham de Ruiter
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Niklas B. Thompson
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Michael K. Takase
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Theodor Agapie
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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192
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Wang B, Lee YM, Clémancey M, Seo MS, Sarangi R, Latour JM, Nam W. Mononuclear Nonheme High-Spin Iron(III)-Acylperoxo Complexes in Olefin Epoxidation and Alkane Hydroxylation Reactions. J Am Chem Soc 2016; 138:2426-36. [DOI: 10.1021/jacs.5b13500] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Bin Wang
- Department
of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Yong-Min Lee
- Department
of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Martin Clémancey
- University of Grenoble Alpes, LCBM/PMB and CEA, IRTSV/CBM/PMB and CNRS, LCBM UMR 5249, PMB, 38000 Grenoble, France
| | - Mi Sook Seo
- Department
of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Ritimukta Sarangi
- Stanford
Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, California 94025-7015, United States
| | - Jean-Marc Latour
- University of Grenoble Alpes, LCBM/PMB and CEA, IRTSV/CBM/PMB and CNRS, LCBM UMR 5249, PMB, 38000 Grenoble, France
| | - Wonwoo Nam
- Department
of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
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193
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Bellow JA, Yousif M, Groysman S. Discrete Complexes of 3d Metals with Monodentate Bulky Alkoxide Ligands and Their Reactivity in Bond Activation and Bond Formation Reactions. COMMENT INORG CHEM 2016. [DOI: 10.1080/02603594.2015.1108913] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- James A. Bellow
- Department of Chemistry, Wayne State University, Detroit, Michigan, USA
| | - Maryam Yousif
- Department of Chemistry, Wayne State University, Detroit, Michigan, USA
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194
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Affiliation(s)
- Lawrence Que, Jr.
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota
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195
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Yamagishi H, Nabeya S, Ikariya T, Kuwata S. Protic Ruthenium Tris(pyrazol-3-ylmethyl)amine Complexes Featuring a Hydrogen-Bonding Network in the Second Coordination Sphere. Inorg Chem 2015; 54:11584-6. [DOI: 10.1021/acs.inorgchem.5b02044] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Hiroaki Yamagishi
- Department of Applied
Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku,
Tokyo 152-8552, Japan
| | - Shohei Nabeya
- Department of Applied
Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku,
Tokyo 152-8552, Japan
| | - Takao Ikariya
- Department of Applied
Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku,
Tokyo 152-8552, Japan
| | - Shigeki Kuwata
- Department of Applied
Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku,
Tokyo 152-8552, Japan
- PRESTO, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
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196
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Olivo G, Nardi M, Vìdal D, Barbieri A, Lapi A, Gómez L, Lanzalunga O, Costas M, Di Stefano S. C-H Bond Oxidation Catalyzed by an Imine-Based Iron Complex: A Mechanistic Insight. Inorg Chem 2015; 54:10141-52. [PMID: 26457760 DOI: 10.1021/acs.inorgchem.5b01500] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A family of imine-based nonheme iron(II) complexes (LX)2Fe(OTf)2 has been prepared, characterized, and employed as C-H oxidation catalysts. Ligands LX (X = 1, 2, 3, and 4) stand for tridentate imine ligands resulting from spontaneous condensation of 2-pycolyl-amine and 4-substituted-2-picolyl aldehydes. Fast and quantitative formation of the complex occurs just upon mixing aldehyde, amine, and Fe(OTf)2 in a 2:2:1 ratio in acetonitrile solution. The solid-state structures of (L1)2Fe(OTf)(ClO4) and (L3)2Fe(OTf)2 are reported, showing a low-spin octahedral iron center, with the ligands arranged in a meridional fashion. (1)H NMR analyses indicate that the solid-state structure and spin state is retained in solution. These analyses also show the presence of an amine-imine tautomeric equilibrium. (LX)2Fe(OTf)2 efficiently catalyze the oxidation of alkyl C-H bonds employing H2O2 as a terminal oxidant. Manipulation of the electronic properties of the imine ligand has only a minor impact on efficiency and selectivity of the oxidative process. A mechanistic study is presented, providing evidence that C-H oxidations are metal-based. Reactions occur with stereoretention at the hydroxylated carbon and selectively at tertiary over secondary C-H bonds. Isotopic labeling analyses show that H2O2 is the dominant origin of the oxygen atoms inserted in the oxygenated product. Experimental evidence is provided that reactions involve initial oxidation of the complexes to the ferric state, and it is proposed that a ligand arm dissociates to enable hydrogen peroxide binding and activation. Selectivity patterns and isotopic labeling studies strongly suggest that activation of hydrogen peroxide occurs by heterolytic O-O cleavage, without the assistance of a cis-binding water or alkyl carboxylic acid. The sum of these observations provides sound evidence that controlled activation of H2O2 at (LX)2Fe(OTf)2 differs from that occurring in biomimetic iron catalysts described to date.
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Affiliation(s)
- Giorgio Olivo
- Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza" and Istituto CNR di Metodologie Chimiche (IMC-CNR), Sezione Meccanismi di Reazione, c/o Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza", P.le A. Moro 5, I-00185 Rome, Italy.,Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona , Campus de Montilivi, 17071 Girona, Spain
| | - Martina Nardi
- Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza" and Istituto CNR di Metodologie Chimiche (IMC-CNR), Sezione Meccanismi di Reazione, c/o Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza", P.le A. Moro 5, I-00185 Rome, Italy
| | - Diego Vìdal
- Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona , Campus de Montilivi, 17071 Girona, Spain
| | - Alessia Barbieri
- Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza" and Istituto CNR di Metodologie Chimiche (IMC-CNR), Sezione Meccanismi di Reazione, c/o Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza", P.le A. Moro 5, I-00185 Rome, Italy
| | - Andrea Lapi
- Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza" and Istituto CNR di Metodologie Chimiche (IMC-CNR), Sezione Meccanismi di Reazione, c/o Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza", P.le A. Moro 5, I-00185 Rome, Italy.,Consortium of Chemical Catalysis and Reactivity, CIRCC Interuniversity , Via Celso Ulpiani 27, 70126 Bari, Italy
| | - Laura Gómez
- Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona , Campus de Montilivi, 17071 Girona, Spain.,Serveis Tècnics de Recerca (STR), Universitat de Girona , Parc Cientı́fic i Tecnològic, E-17003 Girona, Spain
| | - Osvaldo Lanzalunga
- Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza" and Istituto CNR di Metodologie Chimiche (IMC-CNR), Sezione Meccanismi di Reazione, c/o Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza", P.le A. Moro 5, I-00185 Rome, Italy.,Consortium of Chemical Catalysis and Reactivity, CIRCC Interuniversity , Via Celso Ulpiani 27, 70126 Bari, Italy
| | - Miquel Costas
- Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona , Campus de Montilivi, 17071 Girona, Spain
| | - Stefano Di Stefano
- Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza" and Istituto CNR di Metodologie Chimiche (IMC-CNR), Sezione Meccanismi di Reazione, c/o Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza", P.le A. Moro 5, I-00185 Rome, Italy.,Consortium of Chemical Catalysis and Reactivity, CIRCC Interuniversity , Via Celso Ulpiani 27, 70126 Bari, Italy
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197
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Baglia RA, Prokop-Prigge KA, Neu HM, Siegler MA, Goldberg DP. Mn(V)(O) versus Cr(V)(O) Porphyrinoid Complexes: Structural Characterization and Implications for Basicity Controlling H-Atom Abstraction. J Am Chem Soc 2015; 137:10874-7. [PMID: 26295412 DOI: 10.1021/jacs.5b05142] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Isomorphous crystals of Mn(V)(O) and Cr(V)(O) corrolazines were characterized by single crystal X-ray diffraction. Reactivity studies with H atom donors and separated PCET reagents show a dramatic difference in H atom abstracting abilities for these two complexes. The implied large difference in driving force is opposite the trend in redox potentials, indicating that basicity is a key factor in determining the striking difference in reactivity for two metal-oxo species in identical ligand environments.
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Affiliation(s)
- Regina A Baglia
- Department of Chemistry, The Johns Hopkins University , 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - Katharine A Prokop-Prigge
- Department of Chemistry, The Johns Hopkins University , 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - Heather M Neu
- Department of Chemistry, The Johns Hopkins University , 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - Maxime A Siegler
- Department of Chemistry, The Johns Hopkins University , 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - David P Goldberg
- Department of Chemistry, The Johns Hopkins University , 3400 North Charles Street, Baltimore, Maryland 21218, United States
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