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Scherz F, Bauer M, Domenianni LI, Hoyer C, Schmidt J, Sarkar B, Vöhringer P, Krewald V. Ultrafast photogeneration of a metal-organic nitrene from 1,1'-diazidoferrocene. Chem Sci 2024; 15:6707-6715. [PMID: 38725494 PMCID: PMC11077559 DOI: 10.1039/d4sc00883a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 04/08/2024] [Indexed: 05/12/2024] Open
Abstract
Ferrocene and its derivatives have fascinated chemists for more than 70 years, not least due to the analogies with the properties of benzene. Despite these similarities, the obvious difference between benzene and ferrocene is the presence of an iron ion and hence the availability of d-orbitals for properties and reactivity. Phenylnitrene with its rich photochemistry can be considered an analogue of nitrenoferrocene. As with most organic and inorganic nitrenes, nitrenoferrocene can be obtained by irradiating the azide precursor. We study the photophysical and photochemical processes of dinitrogen release from 1,1'-diazidoferrocene to form 1-azido-1'-nitrenoferrocene with UV-pump-mid-IR-probe transient absorption spectroscopy and time-dependent density functional theory calculations including spin-orbit coupling. An intermediate with a bent azide moiety is identified that is pre-organised for dinitrogen release via a low-lying transition state. The photochemical decay paths on the singlet and triplet surfaces including the importance of spin-orbit coupling are discussed. We compare our findings with the processes discussed for photochemical dinitrogen activation and highlight implications for the photochemistry of azides more generally.
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Affiliation(s)
- Frederik Scherz
- Department of Chemistry, Theoretical Chemistry, TU Darmstadt Peter-Grünberg-Str. 4 64287 Darmstadt Germany
| | - Markus Bauer
- Clausius-Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität Bonn Wegelerstraße 12 53115 Bonn Germany
| | - Luis I Domenianni
- Clausius-Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität Bonn Wegelerstraße 12 53115 Bonn Germany
| | - Carolin Hoyer
- Institut für Chemie und Biochemie, Freie Universität Berlin Fabeckstraße 34-36 14195 Berlin Germany
| | - Jonas Schmidt
- Clausius-Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität Bonn Wegelerstraße 12 53115 Bonn Germany
| | - Biprajit Sarkar
- Institute of Inorganic Chemistry, University of Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
- Institut für Chemie und Biochemie, Freie Universität Berlin Fabeckstraße 34-36 14195 Berlin Germany
| | - Peter Vöhringer
- Clausius-Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität Bonn Wegelerstraße 12 53115 Bonn Germany
| | - Vera Krewald
- Department of Chemistry, Theoretical Chemistry, TU Darmstadt Peter-Grünberg-Str. 4 64287 Darmstadt Germany
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2
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Bhardwaj A, Mondal B. μ 2 -η 1 :η 1 -N 2 Bridged Bimetallic Dinitrogen Complexes: Geometry of the First Excited State in Connection to N 2 π-Photoactivation. Chemistry 2023; 29:e202301984. [PMID: 37578813 DOI: 10.1002/chem.202301984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 08/08/2023] [Accepted: 08/14/2023] [Indexed: 08/15/2023]
Abstract
Bimetallic end-on μ2 -η1 :η1 -N2 bridging dinitrogen complexes have served as the platform for photochemical N2 activation, mainly for the N-N cleavage. However, the alternate N-N π-photoactivation route has remained largely unexplored. This study strengthens the notion of weakening the N-N bond through the population of π* orbital upon electronic excitation from the ground to the first excited state using four prototypical complexes based on Fe (1), Mo (2), and Ru (3,4). The complexes 1-4 possess characteristic N-N π* based LUMO (π*-π*-π*) centered on their M-N-N-M core, which was earlier postulated to play a central role in the N2 photoactivation. Vertical electronic excitation of the highest oscillator strength involves transitions to the N-N π*-based acceptor orbital (π*-π*-π*) in complexes 1-4. This induces geometry relaxation of the first excited metal-to-nitrogen (π*) charge transfer (1 MNCT) state leading to a "zigzag" M-N-N-M core in the equilibrium structure. Obtaining the equilibrium geometry in the first excited state with the full-sized complexes widens the scope of N-N π-photoactivation with μ2 -η1 :η1 -N2 bridging dinitrogen complexes. Promisingly, the elongated N-N bond and bent ∠MNN angle in the photoexcited S1 state of 1-4 resemble their radical- and di-anion forms, which lead toward thermodynamically feasible N-N protonation in the S1 excited state.
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Affiliation(s)
- Akhil Bhardwaj
- School of Chemical Sciences, Indian Institute of Technology Mandi, Himachal, Pradesh, 175075, India
| | - Bhaskar Mondal
- School of Chemical Sciences, Indian Institute of Technology Mandi, Himachal, Pradesh, 175075, India
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3
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Garrido-Barros P, Chalkley MJ, Peters JC. Light Alters the NH 3 vs N 2 H 4 Product Profile in Iron-catalyzed Nitrogen Reduction via Dual Reactivity from an Iron Hydrazido (Fe=NNH 2 ) Intermediate. Angew Chem Int Ed Engl 2023; 62:e202216693. [PMID: 36592374 PMCID: PMC9998131 DOI: 10.1002/anie.202216693] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 01/01/2023] [Accepted: 01/02/2023] [Indexed: 01/03/2023]
Abstract
Whereas synthetically catalyzed nitrogen reduction (N2 R) to produce ammonia is widely studied, catalysis to instead produce hydrazine (N2 H4 ) has received less attention despite its considerable mechanistic interest. Herein, we disclose that irradiation of a tris(phosphine)borane (P3 B ) Fe catalyst, P3 B Fe+ , significantly alters its product profile to increase N2 H4 versus NH3 ; P3 B Fe+ is otherwise known to be highly selective for NH3 . We posit a key terminal hydrazido intermediate, P3 B Fe=NNH2 , as selectivity-determining. Whereas its singlet ground state undergoes protonation to liberate NH3 , a low-lying triplet excited state leads to reactivity at Nα and formation of N2 H4 . Associated electrochemical and spectroscopic studies establish that N2 H4 lies along a unique product pathway; NH3 is not produced from N2 H4 . Our findings are distinct from the canonical mechanism for hydrazine formation, which proceeds via a diazene (HN=NH) intermediate and showcase light as a tool to tailor selectivity.
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Affiliation(s)
- Pablo Garrido-Barros
- Division of Chemistry and Chemical Engineering, California Institute of Technology (Caltech), 1200 E California Blvd, Pasadena, CA-91125, USA
| | - Matthew J Chalkley
- Division of Chemistry and Chemical Engineering, California Institute of Technology (Caltech), 1200 E California Blvd, Pasadena, CA-91125, USA
| | - Jonas C Peters
- Division of Chemistry and Chemical Engineering, California Institute of Technology (Caltech), 1200 E California Blvd, Pasadena, CA-91125, USA
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4
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Park SV, Corcos AR, Jambor AN, Yang T, Berry JF. Formation of the N≡N Triple Bond from Reductive Coupling of a Paramagnetic Diruthenium Nitrido Compound. J Am Chem Soc 2022; 144:3259-3268. [PMID: 35133829 DOI: 10.1021/jacs.1c13396] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Construction of nitrogen-nitrogen triple bonds via homocoupling of metal nitrides is an important fundamental reaction relevant to a potential Nitrogen Economy. Here, we report that room temperature photolysis of Ru2(chp)4N3 (chp- = 2-chloro-6-hydroxypyridinate) in CH2Cl2 produces N2 via reductive coupling of Ru2(chp)4N nitrido species. Computational analysis reveals that the nitride coupling transition state (TS) features an out-of-plane "zigzag" geometry instead of the anticipated planar zigzag TS. However, with intentional exclusion of dispersion correction, the planar zigzag TS geometry can also be found. Both the out-of-plane and planar zigzag TS geometries feature two important types of orbital interactions: (1) donor-acceptor interactions involving intermolecular donation of a nitride lone pair into an empty Ru-N π* orbital and (2) Ru-N π to Ru-N π* interactions derived from coupling of nitridyl radicals. The relative importance of these two interactions is quantified both at and after the TS. Our analysis shows that both interactions are important for the formation of the N-N σ bond, while radical coupling interactions dominate the formation of N-N π bonds. Comparison is made to isoelectronic Ru2-oxo compounds. Formation of an O-O bond via bimolecular oxo coupling is not observed experimentally and is calculated to have a much higher TS energy. The major difference between the nitrido and oxo systems stems from an extremely large driving force, ∼-500 kJ/mol, for N-N coupling vs a more modest driving force for O-O coupling, -40 to -140 kJ/mol.
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Affiliation(s)
- Sungho V Park
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Amanda R Corcos
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Alexander N Jambor
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Tzuhsiung Yang
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - John F Berry
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
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5
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Forrest SJK, Schluschaß B, Yuzik-Klimova EY, Schneider S. Nitrogen Fixation via Splitting into Nitrido Complexes. Chem Rev 2021; 121:6522-6587. [DOI: 10.1021/acs.chemrev.0c00958] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sebastian J. K. Forrest
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstrasse 4, D-37077 Göttingen, Germany
| | - Bastian Schluschaß
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstrasse 4, D-37077 Göttingen, Germany
| | | | - Sven Schneider
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstrasse 4, D-37077 Göttingen, Germany
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6
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Abstract
Our planet urgently needs sustainable solutions to alleviate the anthropogenic global warming and climate change. Homogeneous catalysis has the potential to play a fundamental role in this process, providing novel, efficient, and at the same time eco-friendly routes for both chemicals and energy production. In particular, pincer-type ligation shows promising properties in terms of long-term stability and selectivity, as well as allowing for mild reaction conditions and low catalyst loading. Indeed, pincer complexes have been applied to a plethora of sustainable chemical processes, such as hydrogen release, CO2 capture and conversion, N2 fixation, and biomass valorization for the synthesis of high-value chemicals and fuels. In this work, we show the main advances of the last five years in the use of pincer transition metal complexes in key catalytic processes aiming for a more sustainable chemical and energy production.
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7
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Rupp S, Plasser F, Krewald V. Multi‐Tier Electronic Structure Analysis of Sita's Mo and W Complexes Capable of Thermal or Photochemical N
2
Splitting. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.201901304] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Severine Rupp
- Fachbereich Chemie Theoretische Chemie Technische Universität Darmstadt Alarich‐Weiss‐Str. 4 64287 Darmstadt Germany
| | - Felix Plasser
- Department of Chemistry Loughborough University Loughborough LE11 3TU United Kingdom
| | - Vera Krewald
- Fachbereich Chemie Theoretische Chemie Technische Universität Darmstadt Alarich‐Weiss‐Str. 4 64287 Darmstadt Germany
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8
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Complete cleavage of the N≡N triple bond by Ta 2N + via degenerate ligand exchange at ambient temperature: A perfect catalytic cycle. Proc Natl Acad Sci U S A 2019; 116:21416-21420. [PMID: 31591230 DOI: 10.1073/pnas.1913664116] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
An unprecedented, spontaneous, and complete cleavage of the triple bond of N2 in the thermal reaction of 15N2 with Ta2 14N+ was observed experimentally by Fourier transform ion cyclotron resonance mass spectrometry; mechanistic aspects of the degenerate ligand exchange were addressed by high-level quantum chemical calculations. The "hidden" dis- and reassembly of N2, mediated by Ta2N+, constitutes a full catalytic cycle. A frontier orbital analysis reveals that the scission of the N2 triple bond is essentially governed by the donation of d-electrons from the 2 metal centers into antibonding π*-orbitals of N2 and by the concurrent migration of electrons from bonding π- and σ-orbitals of N2 into empty d-orbitals of the metals. This work may contribute to a rational design of catalysts in order to reduce the still enormous energy demand required for an artificial dinitrogen activation.
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9
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Krewald V. Steric Switching From Photochemical to Thermal N 2 Splitting: A Computational Analysis of the Isomerization Reaction {(Cp *)(Am)Mo} 2(μ-η 1:η 1-N 2) → {(Cp *)(Am)Mo} 2(μ-N) 2. Front Chem 2019; 7:352. [PMID: 31165063 PMCID: PMC6535493 DOI: 10.3389/fchem.2019.00352] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 04/29/2019] [Indexed: 11/13/2022] Open
Abstract
A μ-η1:η1-N2-bridged Mo dimer, {(η5-C5Me5)[N(Et)C(Ph)N(Et)]Mo}2(μ-N2), cleaves dinitrogen thermally resulting in a crystallographically characterized bis-μ-N-bridged dimer, {(η5-C5Me5)[N(Et)C(Ph)N(Et)]Mo}2(μ-N)2. A structurally related Mo dimer with a bulkier amidinate ligand, ([N(iPr)C(Me)N(iPr)]), is only capable of photochemical dinitrogen activation. These opposing reactivities were rationalized as steric switching between the thermally and photochemically active species. A computational analysis of the geometric and electronic structures of intermediates along the isomerization pathway from Mo2(μ-η1:η1-N2) to Mo2(μ-η2:η1-N2) and Mo2(μ-η2:η2-N2), and finally Mo2(μ-N)2, is presented here. The extent to which dispersion affects the thermodynamics of the isomers is evaluated, and it is found that dispersion interactions play a significant role in stabilizing the product and making the reaction exergonic. The concept of steric switching is further explored with theoretical models with sterically even less demanding ligands, indicating that systematic ligand modifications could be used to rationally design the N2 activation energy landscape. An analysis of electronic excitations in the computed UV-vis spectra of the two complexes shows that a particular type of asymmetric excitations is only present in the photoactive complex.
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Affiliation(s)
- Vera Krewald
- Theoretische Chemie, Fachbereich Chemie, TU Darmstadt, Darmstadt, Germany
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10
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Krewald V, González L. A Valence-Delocalised Osmium Dimer capable of Dinitrogen Photocleavage: Ab Initio Insights into Its Electronic Structure. Chemistry 2018; 24:5112-5123. [DOI: 10.1002/chem.201704651] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Vera Krewald
- Institute for Theoretical Chemistry, Faculty of Chemistry; University of Vienna; Währingerstr. 17 1090 Vienna Austria
- Department of Chemistry; University of Bath; Claverton Down Bath BA2 7AY UK
| | - Leticia González
- Institute for Theoretical Chemistry, Faculty of Chemistry; University of Vienna; Währingerstr. 17 1090 Vienna Austria
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11
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Abstract
New perspectives for dinitrogen activation: an overview of photochemical pathways to cleave the strong N–N bond.
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12
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Functionalization of N2 by Mid to Late Transition Metals via N–N Bond Cleavage. TOP ORGANOMETAL CHEM 2017. [DOI: 10.1007/3418_2016_12] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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13
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Tanaka H, Nishibayashi Y, Yoshizawa K. Interplay between Theory and Experiment for Ammonia Synthesis Catalyzed by Transition Metal Complexes. Acc Chem Res 2016; 49:987-95. [PMID: 27105472 DOI: 10.1021/acs.accounts.6b00033] [Citation(s) in RCA: 149] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Nitrogen fixation is an essential chemical process both biologically and industrially. Since the discovery of the first transition-metal-dinitrogen complex in 1965, a great deal of effort has been devoted to the development of artificial nitrogen fixation systems that work under mild reaction conditions. However, the transformation of chemically inert dinitrogen using homogeneous catalysts is still challenging because of the difficulty in breaking the strong triple bond of dinitrogen, and a very limited number of transition metal complexes have exhibited the catalytic activity for the direct transformation of dinitrogen into ammonia with low turnover numbers. To develop more effective nitrogen fixation systems, it is necessary to retrieve as much information as possible from the limited successful examples. Computational chemistry will provide valuable insights in the understanding of the reaction mechanisms involving unstable intermediates that are hard to isolate or characterize. We have been applying it for clarifying detailed mechanisms of dinitrogen activation and functionalization by transition metal complexes as well as for designing new catalysts for more effective nitrogen fixation. This Account summarizes recent progress in the elucidation of catalytic mechanisms of nitrogen fixation by using mono- and dinuclear molybdenum complexes, as well as cubane-type metal-sulfido clusters from a theoretical point of view. First, we briefly introduce experimental and theoretical contributions to the elucidation of the reaction mechanism of nitrogen fixation catalyzed by a mononuclear Mo-triamidoamine complex. Special attention is paid to our recent studies on Mo-catalyzed nitrogen fixation using dinitrogen-bridged dimolybdenum complexes. A possible catalytic mechanism is proposed based on theoretical and experimental investigations. The catalytic mechanism involves the formation of a monuclear molybdenum-nitride (Mo≡N) intermediate, as well as the regeneration of a dimolybdenum intermediate with the Mo-N≡N-Mo moiety. Comparison of the reactivity of di- and monomolybdenum complexes suggests that the dimolybdenum structure is essential for the catalytic activity. Synergy between the two Mo cores connected with a bridging N2 ligand is observed in the protonation of coordinated N2. Intermetallic electron transfer through the bridging N2 ligand reductively activates the coordinated N2 to be protonated. On the basis of the proposed catalytic mechanism, we used DFT calculations for rational design of dimolybdenum complexes serving as more effective catalysts for nitrogen fixation. Newly prepared dimolybdenum complexes with modified PNP-type pincer ligands exhibit greater catalytic activity than the original one.
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Affiliation(s)
- Hiromasa Tanaka
- Institute for Materials
Chemistry and Engineering, Kyushu University, Nishi-ku, Fukuoka 819-0395, Japan
| | - Yoshiaki Nishibayashi
- Department of Systems Innovation, School
of Engineering, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Kazunari Yoshizawa
- Institute for Materials
Chemistry and Engineering, Kyushu University, Nishi-ku, Fukuoka 819-0395, Japan
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14
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Huss AS, Curley JJ, Cummins CC, Blank DA. Relaxation and dissociation following photoexcitation of the (μ-N2)[Mo(N[t-Bu]Ar)3]2 dinitrogen cleavage intermediate. J Phys Chem B 2013; 117:1429-36. [PMID: 23249096 DOI: 10.1021/jp310122x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Frequency resolved pump-probe spectroscopy was performed on isolated (μ-N(2))[Mo(N[t-Bu]Ar)(3)](2) (Ar = 3,5-C(6)H(3)Me(2)), an intermediate formed in the reaction of Mo(N[t-Bu]Ar)(3) to bind and cleave dinitrogen. Evidence is presented for 300 fs internal conversion followed by subpicosecond vibrational cooling on the ground electronic state in competition with bond dissociation. Fast cooling following photoexcitation leads to a relatively low overall dissociation yield of 5%, in quantitative agreement with previous work [Curley, J. J.; Cooke, T. R.; Reece, S. Y.; Mueller, P.; Cummins, C. C. J. Am. Chem. Soc. 2008, 130, 9394]. Coupling of vibrational modes to the excitation and internal conversion results in a nonthermal distribution of energy following conversion, and this provides sufficient bias to allow the nitrogen cleavage reaction to compete with breaking of the Mo-NN bond despite a higher energetic barrier on the ground state.
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Affiliation(s)
- Adam S Huss
- Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, USA
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15
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Furukawa S, Hitomi Y, Shishido T, Teramura K, Tanaka T. π Back-bonding of iron(II) complexes supported by tris(pyrid-2-ylmethyl)amine and its nitro-substituted derivatives. J Phys Chem A 2011; 115:13589-95. [PMID: 21992441 DOI: 10.1021/jp2069539] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The electronic and geometric structures of a series of iron(II) complexes supported by tetradentate tris(pyrid-2-ylmethyl)amine-type ligands with different numbers of 4-nitropyridine groups, [(PyCH(2))(3-n)(4-NO(2)PyCH(2))(n)N] (n = 0-3), were examined by X-ray absorption fine-structure and variable-temperature (1)H NMR spectroscopies and theoretical calculations to reveal how the low-spin state is stabilized through π back-bonding interactions between iron(II) and 4-nitropyridine donor group(s).
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Affiliation(s)
- Shinya Furukawa
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto, Japan
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16
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Kirchner B, di Dio PJ, Hutter J. Real-world predictions from ab initio molecular dynamics simulations. Top Curr Chem (Cham) 2011; 307:109-53. [PMID: 21842358 DOI: 10.1007/128_2011_195] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
In this review we present the techniques of ab initio molecular dynamics simulation improved to its current stage where the analysis of existing processes and the prediction of further chemical features and real-world processes are feasible. For this reason we describe the relevant developments in ab initio molecular dynamics leading to this stage. Among them, parallel implementations, different basis set functions, density functionals, and van der Waals corrections are reported. The chemical features accessible through AIMD are discussed. These are IR, NMR, as well as EXAFS spectra, sampling methods like metadynamics and others, Wannier functions, dipole moments of molecules in condensed phase, and many other properties. Electrochemical reactions investigated by ab initio molecular dynamics methods in solution, on surfaces as well as complex interfaces, are also presented.
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Affiliation(s)
- Barbara Kirchner
- Wilhelm-Ostwald Institute of Physical and Theoretical Chemistry, University of Leipzig, Linnéstr. 2, 04103 Leipzig, Germany.
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17
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Sokolov AY, Schaefer HF. Coordination Properties of Bridging Diazene Ligands in Unusual Diiron Complexes. Organometallics 2010. [DOI: 10.1021/om100098t] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Alexander Yu. Sokolov
- Center for Computational Quantum Chemistry, University of Georgia, Athens, Georgia 30602
| | - Henry F. Schaefer
- Center for Computational Quantum Chemistry, University of Georgia, Athens, Georgia 30602
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18
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Field LD, Li HL, Dalgarno SJ. Side-on Bound Diazene and Hydrazine Complexes of Ruthenium. Inorg Chem 2010; 49:6214-21. [DOI: 10.1021/ic100821u] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Leslie D. Field
- School of Chemistry, University of New South Wales, NSW 2052, Australia
| | - Hsiu L. Li
- School of Chemistry, University of New South Wales, NSW 2052, Australia
| | - Scott J. Dalgarno
- School of EPS-Chemistry, Heriot-Watt University, Edinburgh, Scotland EH14 4AS, U.K
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19
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Manzur C, Fuentealba M, Hamon JR, Carrillo D. Cationic organoiron mixed-sandwich hydrazine complexes: Reactivity toward aldehydes, ketones, β-diketones and dioxomolybdenum complexes. Coord Chem Rev 2010. [DOI: 10.1016/j.ccr.2009.11.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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20
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Tanaka H, Ohsako F, Seino H, Mizobe Y, Yoshizawa K. Theoretical Study on Activation and Protonation of Dinitrogen on Cubane-Type MIr3S4 Clusters (M = V, Cr, Mn, Fe, Co, Ni, Cu, Mo, Ru, and W). Inorg Chem 2010; 49:2464-70. [DOI: 10.1021/ic902414n] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hiromasa Tanaka
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Fumihiro Ohsako
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Hidetake Seino
- Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan
| | - Yasushi Mizobe
- Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan
| | - Kazunari Yoshizawa
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
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21
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Tanaka H, Shiota Y, Matsuo T, Kawaguchi H, Yoshizawa K. DFT Study on N2 Activation by a Hydride-Bridged Diniobium Complex. N≡N Bond Cleavage Accompanied by H2 Evolution. Inorg Chem 2009; 48:3875-81. [DOI: 10.1021/ic802377p] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Hiromasa Tanaka
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka, Japan 819-0395, Functional Elemento-Organic Chemistry Unit, RIKEN, Wako, Saitama, Japan 351-0198, and Department of Chemistry, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo, Japan 152-8551
| | - Yoshihito Shiota
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka, Japan 819-0395, Functional Elemento-Organic Chemistry Unit, RIKEN, Wako, Saitama, Japan 351-0198, and Department of Chemistry, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo, Japan 152-8551
| | - Tsukasa Matsuo
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka, Japan 819-0395, Functional Elemento-Organic Chemistry Unit, RIKEN, Wako, Saitama, Japan 351-0198, and Department of Chemistry, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo, Japan 152-8551
| | - Hiroyuki Kawaguchi
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka, Japan 819-0395, Functional Elemento-Organic Chemistry Unit, RIKEN, Wako, Saitama, Japan 351-0198, and Department of Chemistry, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo, Japan 152-8551
| | - Kazunari Yoshizawa
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka, Japan 819-0395, Functional Elemento-Organic Chemistry Unit, RIKEN, Wako, Saitama, Japan 351-0198, and Department of Chemistry, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo, Japan 152-8551
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22
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Curley JJ, Cook TR, Reece SY, Müller P, Cummins CC. Shining Light on Dinitrogen Cleavage: Structural Features, Redox Chemistry, and Photochemistry of the Key Intermediate Bridging Dinitrogen Complex. J Am Chem Soc 2008; 130:9394-405. [PMID: 18576632 DOI: 10.1021/ja8002638] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- John J. Curley
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Room 6-325, Cambridge, Massachusetts 02139
| | - Timothy R. Cook
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Room 6-325, Cambridge, Massachusetts 02139
| | - Steven Y. Reece
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Room 6-325, Cambridge, Massachusetts 02139
| | - Peter Müller
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Room 6-325, Cambridge, Massachusetts 02139
| | - Christopher C. Cummins
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Room 6-325, Cambridge, Massachusetts 02139
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23
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Tanaka H, Mori H, Seino H, Hidai M, Mizobe Y, Yoshizawa K. DFT Study on Chemical N2 Fixation by Using a Cubane-Type RuIr3S4 Cluster: Energy Profile for Binding and Reduction of N2 to Ammonia via Ru−N−NHx (x = 1−3) Intermediates with Unique Structures. J Am Chem Soc 2008; 130:9037-47. [DOI: 10.1021/ja8009567] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Hiromasa Tanaka
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan, Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan, and Department of Materials Science and Technology, Faculty of Industrial Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Hiroyuki Mori
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan, Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan, and Department of Materials Science and Technology, Faculty of Industrial Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Hidetake Seino
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan, Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan, and Department of Materials Science and Technology, Faculty of Industrial Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Masanobu Hidai
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan, Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan, and Department of Materials Science and Technology, Faculty of Industrial Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Yasushi Mizobe
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan, Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan, and Department of Materials Science and Technology, Faculty of Industrial Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Kazunari Yoshizawa
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan, Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan, and Department of Materials Science and Technology, Faculty of Industrial Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
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24
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Schenk S, Le Guennic B, Kirchner B, Reiher M. First-Principles Investigation of the Schrock Mechanism of Dinitrogen Reduction Employing the Full HIPTN3N Ligand. Inorg Chem 2008; 47:3634-50. [DOI: 10.1021/ic702083p] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Stephan Schenk
- Laboratorium für Physikalische Chemie, ETH Zürich, Wolfgang-Pauli-Strasse 10, CH-8093 Zürich, Switzerland, Laboratoire de Chimie, Ecole Normale Supérieure de Lyon, 46 Allée d’Italie, F-69364 Lyon Cedex 07, France, and Chair of Theoretical Chemistry, University of Leipzig, Linnestrasse 2, D-04103 Leipzig, Germany
| | - Boris Le Guennic
- Laboratorium für Physikalische Chemie, ETH Zürich, Wolfgang-Pauli-Strasse 10, CH-8093 Zürich, Switzerland, Laboratoire de Chimie, Ecole Normale Supérieure de Lyon, 46 Allée d’Italie, F-69364 Lyon Cedex 07, France, and Chair of Theoretical Chemistry, University of Leipzig, Linnestrasse 2, D-04103 Leipzig, Germany
| | - Barbara Kirchner
- Laboratorium für Physikalische Chemie, ETH Zürich, Wolfgang-Pauli-Strasse 10, CH-8093 Zürich, Switzerland, Laboratoire de Chimie, Ecole Normale Supérieure de Lyon, 46 Allée d’Italie, F-69364 Lyon Cedex 07, France, and Chair of Theoretical Chemistry, University of Leipzig, Linnestrasse 2, D-04103 Leipzig, Germany
| | - Markus Reiher
- Laboratorium für Physikalische Chemie, ETH Zürich, Wolfgang-Pauli-Strasse 10, CH-8093 Zürich, Switzerland, Laboratoire de Chimie, Ecole Normale Supérieure de Lyon, 46 Allée d’Italie, F-69364 Lyon Cedex 07, France, and Chair of Theoretical Chemistry, University of Leipzig, Linnestrasse 2, D-04103 Leipzig, Germany
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25
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Studt F, Tuczek F. Theoretical, spectroscopic, and mechanistic studies on transition-metal dinitrogen complexes: implications to reactivity and relevance to the nitrogenase problem. J Comput Chem 2007; 27:1278-91. [PMID: 16786542 DOI: 10.1002/jcc.20413] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Dinitrogen complexes of transition metals exhibit different binding geometries of N2 (end-on terminal, end-on bridging, side-on bridging, side-on end-on bridging), which are investigated by spectroscopy and DFT calculations, analyzing their electronic structure and reactivity. For comparison, a bis(mu-nitrido) complex, where the N--N bond has been split, has been studied as well. Most of these systems are highly covalent, and have strong metal-nitrogen bonds. In the present review, particular emphasis is put on a consideration of the activation of the coordinated dinitrogen ligand, making it susceptible to protonation, reactions with electrophiles or cleavage. In this context, theoretical, structural, and spectroscopic data giving informations on the amount of charge on the N2 unit are presented. The orbital interactions leading to a charge transfer from the metals to the dinitrogen ligand and the charge distribution within the coordinated N2 group are analyzed. Correlations between the binding mode and the observed reactivity of N2 are discussed.
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Affiliation(s)
- Felix Studt
- Institut für Anorganische Chemie, Christian-Albrechts-Universität Kiel, Otto Hahn Platz 6/7, 24098 Kiel, Germany
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26
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McKee ML. Modeling the nitrogenase FeMo cofactor with high-spin Fe8
S9
X+
(XN, C) clusters. Is the first step for N2
reduction to NH3
a concerted dihydrogen transfer? J Comput Chem 2007; 28:1342-56. [PMID: 17318945 DOI: 10.1002/jcc.20635] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
A high-spin Fe(8)S(9)X(+) (X=N, C) cluster is used to model the reduction of molecular nitrogen to ammonia by the nitrogenase FeMo cofactor at the B3LYP/6-311G(d,p)/ECP(Fe,SDD) level of theory. A total of seventy-three structures were optimized (including three transition state optimizations) to explore the structure and energetic of N(2), C(2)H(2), and CO coordination to the Fe(8)S(9)X(+) cluster. After three protonation-reduction (PR) steps (modeled by addition of hydrogen atoms), N(2), C(2)H(2), and CO are predicted to bind to a Fe atom in the exo (cage does not open) position with binding energies of 7.6, 14.7, and 11.7 kcal/mol. With additional PR steps the coordination number of the core nitrogen atom is reduced from six to five and the bridging thiol group becomes a terminal SH(2) group. The fifth and sixth PR steps occur on the core nitrogen and the open Fe site. Coordination of N(2) is enhanced after six PR steps to give an intermediate ideally suited for a concerted dihydrogen transfer from the Fe and core nitrogen atoms to the coordinated N(2). The identity of the central atom (nitrogen or carbon) has only a minor effect on the reaction steps.
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Affiliation(s)
- Michael L McKee
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, USA.
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27
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Himmel HJ, Reiher M. Intrinsische Stickstoff-Aktivierung an “nackten” Metallatomen. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200502892] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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28
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Abstract
There is ongoing interest in metal complexes which bind dinitrogen and facilitate either its reduction or oxidation under mild conditions. In nature, the enzyme nitrogenase catalyzes this process, and dinitrogen fixation occurs under mild and ambient conditions at a metal-sulfur cluster in the center of the MoFe protein, but the mechanism of this process remains largely unknown. In the last few years, new important discoveries have been made in this field. In this review are discussed recent findings on the interaction of N(2) with metal atoms and metal-atom dimers from all groups of the periodic table as provided by gas-phase as well as matrix-isolation experiments. Intrinsic dinitrogen activation at such bare metal atoms is then related to corresponding processes at complexes, clusters, and surfaces.
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Affiliation(s)
- Hans-Jörg Himmel
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.
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29
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Muñiz K, Nieger M. Catalytic Activation of NN Multiple Bonds: A Homogeneous Palladium Catalyst for Mechanistically Unprecedented Reduction of Azo Compounds. Angew Chem Int Ed Engl 2006; 45:2305-8. [PMID: 16518789 DOI: 10.1002/anie.200503875] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Kilian Muñiz
- Faculté de Chimie, Institut Le Bel, Université Louis Pasteur, 4, rue Blaise Pascal, 67070 Strasbourg Cedex, France.
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30
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Muñiz K, Nieger M. Katalytische Aktivierung von N-N-Mehrfachbindungen: ein definierter homogener Palladiumkatalysator zur mechanistisch neuartigen Reduktion von Azoverbindungen. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200503875] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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31
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Kuganathan N, Green JC, Himmel HJ. Dinitrogen fixation and activation by Ti and Zr atoms, clusters and complexes. NEW J CHEM 2006. [DOI: 10.1039/b606328d] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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32
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Le Guennic B, Kirchner B, Reiher M. Nitrogen Fixation under Mild Ambient Conditions: Part I—The Initial Dissociation/Association Step at Molybdenum Triamidoamine Complexes. Chemistry 2005; 11:7448-60. [PMID: 16267863 DOI: 10.1002/chem.200500935] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In several recent studies Schrock and collaborators demonstrated for the first time how molecular dinitrogen can be catalytically transformed under mild and ambient conditions to ammonia by a molybdenum triamidoamine complex. In this work, we investigate the geometrical and electronic structures involved in this process of dinitrogen activation with quantum chemical methods. Density functional theory (DFT) has been employed to calculate the coordination energies of ammonia and dinitrogen relevant for the dissociation/association step in which ammonia is substituted by dinitrogen. In the DFT calculations the triamidoamine chelate ligand has been modeled by a systematic hierarchy of increasingly complex substituents at the amide nitrogen atoms. The most complex ligand considered is an experimentally known ligand with an HMT = 3,5-(2,4,6-Me3C6H2)2C6H3 substituent. Several assumptions by Schrock and collaborators on key reaction steps are confirmed by our calculations. Additional information is provided on many species not yet observed experimentally. Particular attention is paid to the role of the charge of the complexes. The investigation demonstrates that dinitrogen coordination is enhanced for the negatively charged metal fragment, that is, coordination is more favorable for the anionic metal fragment than for the neutral species. Coordination of N2 is least favorable for the cationic metal fragment. Furthermore, ammonia abstraction from the cationic complex is energetically unfavorable, while NH3 abstraction is less difficult from the neutral and easily feasible from the anionic low-spin complex.
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Affiliation(s)
- Boris Le Guennic
- Institut für Physikalische Chemie, Universität Jena, Helmholtzweg 4, 07743 Jena, Germany
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33
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Analysis of spin states, spin barriers, and trans-effects involved in the coordination and stabilization of dinitrogen by biomimetic iron complexes. Theor Chem Acc 2005. [DOI: 10.1007/s00214-005-0646-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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34
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Kirchner B, Reiher M, Hille A, Hutter J, Hess BA. Car-Parrinello Molecular Dynamics Study of the Initial Dinitrogen Reduction Step in Sellmann-Type Nitrogenase Model Complexes. Chemistry 2005; 11:574-83. [PMID: 15551315 DOI: 10.1002/chem.200400709] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
We have studied reduction reactions for nitrogen fixation at Sellmann-type model complexes with Car-Parrinello simulation techniques. These dinuclear complexes are especially designed to emulate the so-called open-side FeMoco model. The main result of this work shows that in order to obtain the reduced species several side reactions have to be suppressed. These involve partial dissociation of the chelate ligands and hydrogen atom transfer to the metal center. Working at low temperature turns out to be one necessary pre-requisite in carrying out successful events. The successful events cannot be described by simple reaction coordinates. Complicated processes are involved during the initiation of the reaction. Our theoretical study emphasizes two experimental strategies which are likely to inhibit the side reactions. Clamping of the two metal fragments by a chelating phosphane ligand should prevent dissociation of the complex. Furthermore, introduction of tert-butyl substituents could improve the solubility and should thus allow usage of a wider range of (mild) acids, reductants, and reaction conditions.
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Affiliation(s)
- Barbara Kirchner
- Lehrstuhl für Theoretische Chemie, Universität Bonn, Wegelerstrasse 12, 53115 Bonn, Germany.
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