1
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Liang S, Jensen MP. [Fe(NCMe) 6](BF 4) 2 is a bifunctional catalyst for styrene aziridination by nitrene transfer and heterocycle expansion by subsequent dipolar insertion. J Inorg Biochem 2024; 256:112551. [PMID: 38678911 DOI: 10.1016/j.jinorgbio.2024.112551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 03/24/2024] [Accepted: 04/04/2024] [Indexed: 05/01/2024]
Abstract
The solvated iron(II) salt [Fe(NCMe)6](BF4)2 (Me = methyl) is shown to be a bifunctional catalyst with respect to aziridination of styrene. The salt serves as an active catalyst for nitrene transfer from PhINTs to styrene to form 2-phenyl-N-tosylaziridine (Ph = phenyl; Ts = tosyl, -S{O}2-p-C6H4Me). The iron(II) salt also acts as a Lewis acid in non-coordinating CH2Cl2 solution, to catalyze heterolytic CN bond cleavage of the aziridine and insertion of dipolarophiles. The 1,3-zwitterionic intermediate is presumably supported by interaction of the metal dication with the anion, and by resonance stabilization of the carbocation. Nucleophilic dipolarophiles then insert to give a five-membered heterocyclic ring. The result is a two-step cycloaddition, formally [2 + 1 + 2], that is typically regiospecific, but not stereospecific. This reaction mechanism was confirmed by conducting a series of one-step, [3 + 2] additions of unsaturated molecules into pre-formed 2-phenyl-N-tosylaziridine, also catalyzed by [Fe(NCMe)6](BF4)2. Relevant substrates include styrenes, carbonyl compounds and alkynes. These yield five-membered heterocylic rings, including pyrrolidines, oxazolidines and dihydropyrroles, respectively. The reaction scope appears limited only by the barrier to formation of the dipolar intermediate, and by the nucleophilicity of the captured dipolarophile. The bifunctionality of an inexpensive, earth-abundant and non-toxic catalyst suggests a general strategy for one-pot construction of heterocyclic rings, as demonstrated specifically for pyrrolidine ring formation.
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Affiliation(s)
- Shengwen Liang
- Department of Chemistry and Biochemistry, Ohio University, Athens, OH 45701, USA
| | - Michael P Jensen
- Department of Chemistry and Biochemistry, Ohio University, Athens, OH 45701, USA.
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2
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Stroek W, Keilwerth M, Malaspina LA, Grabowsky S, Meyer K, Albrecht M. Deciphering Iron-Catalyzed C-H Amination with Organic Azides: N 2 Cleavage from a Stable Organoazide Complex. Chemistry 2024; 30:e202303410. [PMID: 37916523 DOI: 10.1002/chem.202303410] [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: 10/18/2023] [Revised: 11/01/2023] [Accepted: 11/02/2023] [Indexed: 11/03/2023]
Abstract
Catalytic C-N bond formation by direct activation of C-H bonds offers wide synthetic potential. En route to C-H amination, complexes with organic azides are critical precursors towards the reactive nitrene intermediate. Despite their relevance, α-N coordinated organoazide complexes are scarce in general, and elusive with iron, although iron complexes are by far the most active catalysts for C-H amination with organoazides. Herein, we report the synthesis of a stable iron α-N coordinated organoazide complex from [Fe(N(SiMe3 )2 )2 ] and AdN3 (Ad=1-adamantyl) and its crystallographic, IR, NMR and zero-field 57 Fe Mössbauer spectroscopic characterization. These analyses revealed that the organoazide is in fast equilibrium between the free and coordinated state (Keq =62). Photo-crystallography experiments showed gradual dissociation of N2 , which imparted an Fe-N bond shortening and correspond to structural snapshots of the formation of an iron imido/nitrene complex. Reactivity of the organoazide complex in solution showed complete loss of N2 , and subsequent formation of a C-H aminated product via nitrene insertion into a C-H bond of the N(SiMe3 )2 ligand. Monitoring this reaction by 1 H NMR spectroscopy indicates the transient formation of the imido/nitrene intermediate, which was supported by Mössbauer spectroscopy in frozen solution.
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Affiliation(s)
- Wowa Stroek
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Martin Keilwerth
- Department of Chemistry and Pharmacy, Inorganic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Egerlandstraße 1, 91058, Erlangen, Germany
| | - Lorraine A Malaspina
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Simon Grabowsky
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Karsten Meyer
- Department of Chemistry and Pharmacy, Inorganic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Egerlandstraße 1, 91058, Erlangen, Germany
| | - Martin Albrecht
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
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3
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Zars E, Pick L, Swain A, Bhunia M, Carroll PJ, Munz D, Meyer K, Mindiola DJ. Iron-Catalyzed Intermolecular C-H Amination Assisted by an Isolated Iron-Imido Radical Intermediate. Angew Chem Int Ed Engl 2023:e202311749. [PMID: 37815099 DOI: 10.1002/anie.202311749] [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: 08/12/2023] [Revised: 10/02/2023] [Accepted: 10/03/2023] [Indexed: 10/11/2023]
Abstract
Here we report the use of a base metal complex [(tBu pyrpyrr2 )Fe(OEt2 )] (1-OEt2 ) (tBu pyrpyrr2 2- =3,5-tBu2 -bis(pyrrolyl)pyridine) as a catalyst for intermolecular amination of Csp3 -H bonds of 9,10-dihydroanthracene (2 a) using 2,4,6-trimethyl phenyl azide (3 a) as the nitrene source. The reaction is complete within one hour at 80 °C using as low as 2 mol % 1-OEt2 with control in selectivity for single C-H amination versus double C-H amination. Catalytic C-H amination reactions can be extended to other substrates such as cyclohexadiene and xanthene derivatives and can tolerate a variety of aryl azides having methyl groups in both ortho positions. Under stoichiometric conditions the imido radical species [(tBu pyrpyrr2 )Fe{=N(2,6-Me2 -4-tBu-C6 H2 )] (1-imido) can be isolated in 56 % yield, and spectroscopic, magnetometric, and computational studies confirmed it to be an S = 1 FeIV complex. Complex 1-imido reacts with 2 a to produce the ferrous aniline adduct [(tBu pyrpyrr2 )Fe{NH(2,6-Me2 -4-tBu-C6 H2 )(C14 H11 )}] (1-aniline) in 45 % yield. Lastly, it was found that complexes 1-imido and 1-aniline are both competent intermediates in catalytic intermolecular C-H amination.
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Affiliation(s)
- Ethan Zars
- Department of Chemistry, University of Pennsylvania, 231 S 34th St, Philadelphia, PA-19104, USA
| | - Lisa Pick
- Department of Chemistry & Pharmacy, Inorganic Chemistry, Friedrich-Alexander-Universität Erlangen - Nürnberg (FAU), 91058, Erlangen, Germany
| | - Abinash Swain
- Inorganic Chemistry: Coordination Chemistry, Saarland University, Campus C4 1, 66123, Saarbrücken, Germany
| | - Mrinal Bhunia
- Department of Chemistry, University of Pennsylvania, 231 S 34th St, Philadelphia, PA-19104, USA
| | - Patrick J Carroll
- Department of Chemistry, University of Pennsylvania, 231 S 34th St, Philadelphia, PA-19104, USA
| | - Dominik Munz
- Inorganic Chemistry: Coordination Chemistry, Saarland University, Campus C4 1, 66123, Saarbrücken, Germany
| | - Karsten Meyer
- Department of Chemistry & Pharmacy, Inorganic Chemistry, Friedrich-Alexander-Universität Erlangen - Nürnberg (FAU), 91058, Erlangen, Germany
| | - Daniel J Mindiola
- Department of Chemistry, University of Pennsylvania, 231 S 34th St, Philadelphia, PA-19104, USA
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4
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Zars E, Gravogl L, Gau MR, Carroll PJ, Meyer K, Mindiola DJ. Isostructural bridging diferrous chalcogenide cores [Fe II(μ-E)Fe II] (E = O, S, Se, Te) with decreasing antiferromagnetic coupling down the chalcogenide series. Chem Sci 2023; 14:6770-6779. [PMID: 37350823 PMCID: PMC10283490 DOI: 10.1039/d3sc01094e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 05/24/2023] [Indexed: 06/24/2023] Open
Abstract
Iron compounds containing a bridging oxo or sulfido moiety are ubiquitous in biological systems, but substitution with the heavier chalcogenides selenium and tellurium, however, is much rarer, with only a few examples reported to date. Here we show that treatment of the ferrous starting material [(tBupyrpyrr2)Fe(OEt2)] (1-OEt2) (tBupyrpyrr2 = 3,5-tBu2-bis(pyrrolyl)pyridine) with phosphine chalcogenide reagents E = PR3 results in the neutral phosphine chalcogenide adduct series [(tBupyrpyrr2)Fe(EPR3)] (E = O, S, Se; R = Ph; E = Te; R = tBu) (1-E) without any electron transfer, whereas treatment of the anionic starting material [K]2[(tBupyrpyrr2)Fe2(μ-N2)] (2-N2) with the appropriate chalcogenide transfer source yields cleanly the isostructural ferrous bridging mono-chalcogenide ate complexes [K]2[(tBupyrpyrr2)Fe2(μ-E)] (2-E) (E = O, S, Se, and Te) having significant deviation in the Fe-E-Fe bridge from linear in the case of E = O to more acute for the heaviest chalcogenide. All bridging chalcogenide complexes were analyzed using a variety of spectroscopic techniques, including 1H NMR, UV-Vis electronic absorbtion, and 57Fe Mössbauer. The spin-state and degree of communication between the two ferrous ions were probed via SQUID magnetometry, where it was found that all iron centers were high-spin (S = 2) FeII, with magnetic exchange coupling between the FeII ions. Magnetic studies established that antiferromagnetic coupling between the ferrous ions decreases as the identity of the chalcogen is tuned from O to the heaviest congener Te.
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Affiliation(s)
- Ethan Zars
- Department of Chemistry, University of Pennsylvania 231 S 34th St Philadelphia PA 19104 USA
| | - Lisa Gravogl
- Department of Chemistry & Pharmacy, Friedrich-Alexander-Universität Erlangen - Nürnberg (FAU) Egerlandstr. 1 91058 Erlangen Bavaria Germany
| | - Michael R Gau
- Department of Chemistry, University of Pennsylvania 231 S 34th St Philadelphia PA 19104 USA
| | - Patrick J Carroll
- Department of Chemistry, University of Pennsylvania 231 S 34th St Philadelphia PA 19104 USA
| | - Karsten Meyer
- Department of Chemistry & Pharmacy, Friedrich-Alexander-Universität Erlangen - Nürnberg (FAU) Egerlandstr. 1 91058 Erlangen Bavaria Germany
| | - Daniel J Mindiola
- Department of Chemistry, University of Pennsylvania 231 S 34th St Philadelphia PA 19104 USA
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5
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Stroek W, Albrecht M. Discovery of a simple iron catalyst reveals the intimate steps of C-H amination to form C-N bonds. Chem Sci 2023; 14:2849-2859. [PMID: 36937598 PMCID: PMC10016609 DOI: 10.1039/d2sc04170g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 12/28/2022] [Indexed: 12/29/2022] Open
Abstract
Formation of ubiquitous C-N bonds traditionally uses prefunctionalized carbon precursors. Recently, metal-catalyzed amination of unfunctionalized C-H bonds with azides has become an attractive and atom-economic strategy for C-N bond formation, though all catalysts contain sophisticated ligands. Here, we report Fe(HMDS)2 (HMDS = N(SiMe3)2 -) as an easy-to-prepare catalyst for intramolecular C-H amination. The catalyst shows unprecedented turnover frequencies (110 h-1 vs. 70 h-1 reported to date) and requires no additives. Amination is successful for benzylic and aliphatic C-H bonds (>80% yield) and occurs even at room temperature. The simplicity of the catalyst enabled for the first time comprehensive mechanistic investigations. Kinetic, stoichiometric, and computational studies unveiled the intimate steps of the C-H amination process, including the resting state of the catalyst and turnover-limiting N2 loss of the coordinated azide. The high reactivity of the iron imido intermediate is rationalized by its complex spin system revealing imidyl and nitrene character.
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Affiliation(s)
- Wowa Stroek
- Department of Chemistry, Biochemistry, and Pharmaceutical Sciences, University of Bern CH-3012 Bern Switzerland
| | - Martin Albrecht
- Department of Chemistry, Biochemistry, and Pharmaceutical Sciences, University of Bern CH-3012 Bern Switzerland
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6
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Xiong J, Liu Q, Lavina B, Hu MY, Zhao J, Alp EE, Deng L, Ye S, Guo Y. Spin polarization assisted facile C-H activation by an S = 1 iron(iv)-bisimido complex: a comprehensive spectroscopic and theoretical investigation. Chem Sci 2023; 14:2808-2820. [PMID: 36937578 PMCID: PMC10016330 DOI: 10.1039/d2sc06273a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 02/14/2023] [Indexed: 02/17/2023] Open
Abstract
High valent iron terminal imido species (Fe[double bond, length as m-dash]NR) have been shown to be key reactive intermediates in C-H functionalization. However, the detailed structure-reactivity relationship in Fe[double bond, length as m-dash]NR species derived from studies of structurally well-characterized high-valent Fe[double bond, length as m-dash]NR complexes are still scarce, and the impact of imido N-substituents (electron-donating vs. electron-withdrawing) on their electronic structures and reactivities has not been thoroughly explored. In this study, we report spectroscopic and computational studies on a rare S = 1 iron(iv)-bisimido complex featuring trifluoromethyl groups on the imido N-substituents, [(IPr)Fe(NC(CF3)2Ph)2] (2), and two closely related S = 0 congeners bearing alkyl and aryl substituents, [(IPr)Fe(NC(CMe3)2Ph)2] (3) and [(IPr)Fe(NDipp)2] (1), respectively. Compared with 1 and 3, 2 exhibits a decreased Fe[double bond, length as m-dash]NR bond covalency due to the electron-withdrawing and the steric effect of the N-substituents, which further leads to a pseudo doubly degenerate ground electronic structure and spin polarization induced β spin density on the imido nitrogens. This unique electronic structure, which differs from those of the well-studied Fe(iv)-oxido complexes and many previously reported Fe(iv)-imido complexes, provides both kinetic and thermodynamic advantages for facile C-H activation, compared to the S = 0 counterparts.
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Affiliation(s)
- Jin Xiong
- Department of Chemistry, Carnegie Mellon University Pittsburgh Pennsylvania 15213 USA
| | - Qing Liu
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences Shanghai 200032 P. R. China
| | - Barbara Lavina
- Advanced Photon Source, Argonne National Laboratory Argonne Illinois 60439 USA
- Center for Advanced Radiation Sources, University of Chicago Chicago Illinois 60439 USA
| | - Michael Y Hu
- Advanced Photon Source, Argonne National Laboratory Argonne Illinois 60439 USA
| | - Jiyong Zhao
- Advanced Photon Source, Argonne National Laboratory Argonne Illinois 60439 USA
| | - Esen E Alp
- Advanced Photon Source, Argonne National Laboratory Argonne Illinois 60439 USA
| | - Liang Deng
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences Shanghai 200032 P. R. China
| | - Shengfa Ye
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences Dalian 116023 P. R. China
| | - Yisong Guo
- Department of Chemistry, Carnegie Mellon University Pittsburgh Pennsylvania 15213 USA
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7
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Souilah C, Jannuzzi SAV, Demirbas D, Ivlev S, Swart M, DeBeer S, Casitas A. Synthesis of Fe
III
and Fe
IV
Cyanide Complexes Using Hypervalent Iodine Reagents as Cyano‐Transfer One‐Electron Oxidants. Angew Chem Int Ed Engl 2022; 61:e202201699. [PMID: 35285116 PMCID: PMC9313551 DOI: 10.1002/anie.202201699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Indexed: 11/12/2022]
Affiliation(s)
- Charafa Souilah
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35043 Marburg Germany
| | - Sergio A. V. Jannuzzi
- Max Planck Institute for Chemical Energy Conversion (MPI CEC) Stiftstraße 34–36 45470 Mülheim an der Ruhr Germany
| | - Derya Demirbas
- Max Planck Institute for Chemical Energy Conversion (MPI CEC) Stiftstraße 34–36 45470 Mülheim an der Ruhr Germany
| | - Sergei Ivlev
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35043 Marburg Germany
| | - Marcel Swart
- ICREA Pg. Lluís Companys 23 08010 Barcelona Spain
- Institut de Química Computacional i Catàlisi, Facultat de Ciències Universitat de Girona c/ M.A. Capmany 69 17003 Girona Spain
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion (MPI CEC) Stiftstraße 34–36 45470 Mülheim an der Ruhr Germany
| | - Alicia Casitas
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35043 Marburg Germany
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8
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Hakey BM, Leary DC, Lopez LM, Valerio LR, Brennessel WW, Milsmann C, Matson EM. Synthesis and Characterization of Pyridine Dipyrrolide Uranyl Complexes. Inorg Chem 2022; 61:6182-6192. [PMID: 35420825 PMCID: PMC9044449 DOI: 10.1021/acs.inorgchem.2c00348] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The first actinide complexes of the pyridine dipyrrolide (PDP) ligand class, (MesPDPPh)UO2(THF) and (Cl2PhPDPPh)UO2(THF), are reported as the UVI uranyl adducts of the bulky aryl substituted pincers (MesPDPPh)2- and (Cl2PhPDPPh)2- (derived from 2,6-bis(5-(2,4,6-trimethylphenyl)-3-phenyl-1H-pyrrol-2-yl)pyridine (H2MesPDPPh, Mes = 2,4,6-trimethylphenyl), and 2,6-bis(5-(2,6-dichlorophenyl)-3-phenyl-1H-pyrrol-2-yl)pyridine (H2Cl2PhPDPPh, Cl2Ph = 2,6-dichlorophenyl), respectively). Following the in situ deprotonation of the proligand with lithium hexamethyldisilazide to generate the corresponding dilithium salts (e.g., Li2ArPDPPh, Ar = Mes of Cl2Ph), salt metathesis with [UO2Cl2(THF)2]2 afforded both compounds in moderate yields. The characterization of each species has been undertaken by a combination of solid- and solution-state methods, including combustion analysis, infrared, electronic absorption, and NMR spectroscopies. In both complexes, single-crystal X-ray diffraction has revealed a distorted octahedral geometry in the solid state, enforced by the bite angle of the rigid meridional (ArPDPPh)2- pincer ligand. The electrochemical analysis of both compounds by cyclic voltammetry in tetrahydrofuran (THF) reveals rich redox profiles, including events assigned as UVI/UV redox couples. A time-dependent density functional theory study has been performed on (MesPDPPh)UO2(THF) and provides insight into the nature of the transitions that comprise its electronic absorption spectrum.
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Affiliation(s)
- Brett M Hakey
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Dylan C Leary
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Lauren M Lopez
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Leyla R Valerio
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - William W Brennessel
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Carsten Milsmann
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Ellen M Matson
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
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9
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Souilah C, Jannuzzi SAV, Demirbas D, Ivlev S, Swart M, DeBeer S, Casitas A. Synthesis of Fe
III
and Fe
IV
Cyanide Complexes Using Hypervalent Iodine Reagents as Cyano‐Transfer One‐Electron Oxidants. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202201699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Charafa Souilah
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35043 Marburg Germany
| | - Sergio A. V. Jannuzzi
- Max Planck Institute for Chemical Energy Conversion (MPI CEC) Stiftstraße 34–36 45470 Mülheim an der Ruhr Germany
| | - Derya Demirbas
- Max Planck Institute for Chemical Energy Conversion (MPI CEC) Stiftstraße 34–36 45470 Mülheim an der Ruhr Germany
| | - Sergei Ivlev
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35043 Marburg Germany
| | - Marcel Swart
- ICREA Pg. Lluís Companys 23 08010 Barcelona Spain
- Institut de Química Computacional i Catàlisi, Facultat de Ciències Universitat de Girona c/ M.A. Capmany 69 17003 Girona Spain
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion (MPI CEC) Stiftstraße 34–36 45470 Mülheim an der Ruhr Germany
| | - Alicia Casitas
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35043 Marburg Germany
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10
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Turner ZR, Wilmore JT, Rees NH, Buffet JC. Sterically rigid bismuth pincer complexes; observation of the growing polymer chain in polar monomer polymerisation. Dalton Trans 2022; 51:3060-3074. [PMID: 35089302 DOI: 10.1039/d1dt04297a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A family of pyridine dipyrrolide bismuth complexes (Mes,PhL)MX (1-6) (M = Bi, X = O-2,6-Me-C6H3 = OXyl (1); M = Sb, X = OXyl (2); M = Bi, X = O-2,6-iPr-C6H3 = ODipp (3), O-2,6-tBu-C6H3 = OArtBu (4), OtBu (5) and OCMe2Et = OAm (6), N(SiMe3)2 = N'' (7) and CH2Ph (8)) have been prepared and investigated as initiators for the ring-opening polymerisation of lactide monomers. Bismuth lactate complexes (Mes,PhL)Bi{OC(H)(Me)C(O)OR} were prepared as models for the propagating species (R = tBu (9), Me (10), iPr (11)). The first insertion of the lactide monomer is rate limiting and the second and subsequent insertions are more rapid (kinit ≪ kLA2 < kprop), leading to a significant induction period. The sterically demanding, rigid pincer ligand affords a well-defined coordination environment at the metal centre and allows for the enchainment of two lactide monomers to be differentiated spectroscopically ((Mes,PhL)Bi{OC(H)(Me)C(O)}4OX (12-X)), with this species also implied to be the true initiator for the regime of propagation with first order kinetics. Well-controlled first order kinetic data for the polymerisation of L-, D-, rac- and meso-lactide are observed.
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Affiliation(s)
- Zoë R Turner
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, OX1 3TA, UK.
| | - Jamie T Wilmore
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, OX1 3TA, UK.
| | - Nicholas H Rees
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, OX1 3TA, UK.
| | - Jean-Charles Buffet
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, OX1 3TA, UK.
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11
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Chatterjee S, Harden I, Bistoni G, Castillo RG, Chabbra S, van Gastel M, Schnegg A, Bill E, Birrell JA, Morandi B, Neese F, DeBeer S. A Combined Spectroscopic and Computational Study on the Mechanism of Iron-Catalyzed Aminofunctionalization of Olefins Using Hydroxylamine Derived N-O Reagent as the "Amino" Source and "Oxidant". J Am Chem Soc 2022; 144:2637-2656. [PMID: 35119853 PMCID: PMC8855425 DOI: 10.1021/jacs.1c11083] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
![]()
Herein, we study
the mechanism of iron-catalyzed direct synthesis
of unprotected aminoethers from olefins by a hydroxyl amine derived
reagent using a wide range of analytical and spectroscopic techniques
(Mössbauer, Electron Paramagnetic Resonance, Ultra-Violet Visible
Spectroscopy, X-ray Absorption, Nuclear Resonance Vibrational Spectroscopy,
and resonance Raman) along with high-level quantum chemical calculations.
The hydroxyl amine derived triflic acid salt acts as the “oxidant”
as well as “amino” group donor. It activates the high-spin
Fe(II) (St = 2) catalyst [Fe(acac)2(H2O)2] (1) to generate
a high-spin (St = 5/2) intermediate (Int I), which decays to a second intermediate (Int II) with St = 2. The analysis of spectroscopic
and computational data leads to the formulation of Int I as [Fe(III)(acac)2-N-acyloxy] (an alkyl-peroxo-Fe(III)
analogue). Furthermore, Int II is formed by N–O
bond homolysis. However, it does not generate a high-valent
Fe(IV)(NH) species (a Fe(IV)(O) analogue), but instead a high-spin
Fe(III) center which is strongly antiferromagnetically coupled (J = −524 cm–1) to an iminyl radical,
[Fe(III)(acac)2-NH·], giving St = 2. Though Fe(NH) complexes as isoelectronic surrogates
to Fe(O) functionalities are known, detection of a high-spin Fe(III)-N-acyloxy intermediate (Int I), which undergoes
N–O bond cleavage to generate the active iron–nitrogen
intermediate (Int II), is unprecedented. Relative to
Fe(IV)(O) centers, Int II features a weak elongated Fe–N
bond which, together with the unpaired electron density along the
Fe–N bond vector, helps to rationalize its propensity for N-transfer reactions onto styrenyl olefins, resulting in
the overall formation of aminoethers. This study thus demonstrates
the potential of utilizing the iron-coordinated nitrogen-centered
radicals as powerful reactive intermediates in catalysis.
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Affiliation(s)
- Sayanti Chatterjee
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany.,Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Ingolf Harden
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Giovanni Bistoni
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Rebeca G Castillo
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Sonia Chabbra
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Maurice van Gastel
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Alexander Schnegg
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Eckhard Bill
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - James A Birrell
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Bill Morandi
- ETH Zürich, Vladimir-Prelog-Weg 3, HCI, 8093 Zürich, Switzerland.,Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Frank Neese
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
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12
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Zars E, Gravogl L, Gau M, Carroll PJ, Meyer K, Mindiola DJ. Iron(II) Mediated Deazotation of Benzyl Azide: Trapping and Subsequent Transformations of the Benzaldimine Fragment. Inorg Chem 2022; 61:1079-1090. [PMID: 34978453 DOI: 10.1021/acs.inorgchem.1c03243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The mono-benzaldimine (HN═CHPh) complex [(tBupyrpyrr2)Fe(HN═CHPh)] (1-HN═CHPh) has been prepared by reaction of [(tBupyrpyrr2)Fe(OEt2)] (1-OEt2) (tBupyrpyrr2 = 2,6-bis(3,5-di-tert-butyl-pyrrolyl)pyridine) with one equivalent of benzyl azide. Compound 1-HN═CHPh retains the cis-divacant octahedral coordination geometry akin to 1, as established by single crystal X-ray diffraction study. A bis-HN═CHPh complex [(tBupyrpyrr2)Fe(HN═CHPh)2] (2) was also prepared by the addition of two equivalents of benzyl azide to 1, and its molecular structure exhibits the two HN═CHPh ligands coordinated trans to each other, thereby forming a square pyramidal coordination geometry at the FeII center. Reaction of 1 with excess benzyl azide yields [(tBupyrpyrr2)Fe(HN═CHPh)2·PhCHNCH(NH2)Ph] (2-PhCHNCH(NH2)Ph), which contains an unstable benzylideneamino phenyl methanamine fragment, effectively hydrogen bonded to 2. Thermolysis of 2 or 2-PhCHNCH(NH2)Ph releases the HN═CHPh self-coupling products hydrobenzamide (A), N-benzylidine benzylamine (B), and benzonitrile (C). Under catalytic conditions, free HN═CHPh (cis/trans-HN═CHPh mixture) is produced using 2.5 mol % of 1 in 90% spectroscopic yield. These studies provide a clearer understanding for the conversion of the HN═CHPh in 2 or 2-PhCHNCH(NH2)Ph to the C-C and C-N coupled products. Reduction of 1-HN═CHPh with KC8 yields the reductively coupled benzylamide complex [K(OEt2)]2[(tBupyrpyrr2)2Fe2(μ2-NHCHPhCHPhNH)] (3) as the result of a new C-C bond formed between two radical benzylamide fragments.
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Affiliation(s)
- Ethan Zars
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Lisa Gravogl
- Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Department of Chemistry and Pharmacy, Inorganic Chemistry, Egerlandstr. 1, Erlangen 91058, Germany
| | - Michael Gau
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Patrick J Carroll
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Karsten Meyer
- Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Department of Chemistry and Pharmacy, Inorganic Chemistry, Egerlandstr. 1, Erlangen 91058, Germany
| | - Daniel J Mindiola
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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13
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Yang PC, Yu KP, Hsieh CT, Zou J, Fang CT, Liu HK, Pao CW, Deng L, Cheng MJ, Lin CY. Stabilization of a high-spin three-coordinate Fe(III) imidyl complex by radical delocalization. Chem Sci 2022; 13:9637-9643. [PMID: 36091897 PMCID: PMC9400638 DOI: 10.1039/d2sc02699f] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 07/04/2022] [Indexed: 11/21/2022] Open
Abstract
High-spin, late transition metal imido complexes have attracted significant interest due to their group transfer reactivity and catalytic C−H activation of organic substrates. Reaction of a new two-coordinate iron complex,...
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Affiliation(s)
- Po-Chun Yang
- Department of Chemistry, National Cheng Kung University No. 1 University Road Tainan 701014 Taiwan
| | - Kuan-Po Yu
- Department of Chemistry, National Cheng Kung University No. 1 University Road Tainan 701014 Taiwan
| | - Chi-Tien Hsieh
- Department of Chemistry, National Cheng Kung University No. 1 University Road Tainan 701014 Taiwan
| | - Junjie Zou
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 P. R. China
| | - Chia-Te Fang
- Department of Chemistry, National Cheng Kung University No. 1 University Road Tainan 701014 Taiwan
| | - Hsin-Kuan Liu
- Core Facility Center, National Cheng Kung University No. 1 University Road Tainan 701014 Taiwan
| | - Chih-Wen Pao
- National Synchrotron Radiation Research Center 101 Hsin-Ann Road Hsinchu 300092 Taiwan
| | - Liang Deng
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 P. R. China
| | - Mu-Jeng Cheng
- Department of Chemistry, National Cheng Kung University No. 1 University Road Tainan 701014 Taiwan
| | - Chun-Yi Lin
- Department of Chemistry, National Cheng Kung University No. 1 University Road Tainan 701014 Taiwan
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14
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Reith S, Demeshko S, Battistella B, Reckziegel A, Schneider C, Stoy A, Lichtenberg C, Meyer F, Munz D, Werncke CG. Between imide, imidyl and nitrene – an imido iron complex in two oxidation states. Chem Sci 2022; 13:7907-7913. [PMID: 35865905 PMCID: PMC9258327 DOI: 10.1039/d2sc01088g] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 05/28/2022] [Indexed: 01/11/2023] Open
Abstract
Imidyl and nitrene metal species play an important role in the N-functionalisation of unreactive C–H bonds as well as the aziridination of olefines. We report on the synthesis of the trigonal imido iron complexes [Fe(NMes)L2]0,− (L = –N{Dipp}SiMe3); Dipp = 2,6-diisopropyl-phenyl; Mes = (2,4,6-trimethylphenyl) via reaction of mesityl azide (MesN3) with the linear iron precursors [FeL2]0,−. UV-vis-, EPR-, 57Fe Mössbauer spectroscopy, magnetometry, and computational methods suggest for the reduced form an electronic structure as a ferromagnetically coupled iron(ii) imidyl radical, whereas oxidation leads to mixed iron(iii) imidyl and electrophilic iron(ii) nitrene character. Reactivity studies show that both complexes are capable of H atom abstraction from C–H bonds. Further, the reduced form [Fe(NMes)L2]− reacts nucleophilically with CS2 by inserting into the imido iron bond, as well as electrophilically with CO under nitrene transfer. The neutral [Fe(NMes)L2] complex shows enhanced electrophilic behavior as evidenced by nitrene transfer to a phosphine, yet in combination with an overall reduced reactivity. A pair of trigonal imido iron complexes ([Fe(NMes)L2]0,−) in two oxidation states is reported. The anionic complex K{crypt.222}[Fe(NMes)L2] is best described as an iron(ii) imide.![]()
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Affiliation(s)
- Sascha Reith
- Philipps-University Marburg, Department of Chemistry, Hans-Meerwein-Str. 4, D-35037 Marburg, Germany
| | - Serhiy Demeshko
- University of Göttingen, Institute of Inorganic Chemistry, Tammannstr. 4, D-37077 Göttingen, Germany
| | - Beatrice Battistella
- Humboldt-University, Berlin Institute for Chemistry, Brook-Taylor-Str. 2, D-12489 Berlin, Germany
| | - Alexander Reckziegel
- Philipps-University Marburg, Department of Chemistry, Hans-Meerwein-Str. 4, D-35037 Marburg, Germany
| | - Christian Schneider
- Philipps-University Marburg, Department of Chemistry, Hans-Meerwein-Str. 4, D-35037 Marburg, Germany
| | - Andreas Stoy
- Philipps-University Marburg, Department of Chemistry, Hans-Meerwein-Str. 4, D-35037 Marburg, Germany
| | - Crispin Lichtenberg
- Philipps-University Marburg, Department of Chemistry, Hans-Meerwein-Str. 4, D-35037 Marburg, Germany
| | - Franc Meyer
- University of Göttingen, Institute of Inorganic Chemistry, Tammannstr. 4, D-37077 Göttingen, Germany
| | - Dominik Munz
- Saarland University, Inorganic Chemistry: Coordination Chemistry, Campus C4.1, D-66123 Saarbrücken, Germany
- Friedrich-Alexander University Erlangen-Nürnberg, Inorganic Chemistry, Egerlandstr. 1, D-91058 Erlangen, Germany
| | - C. Gunnar Werncke
- Philipps-University Marburg, Department of Chemistry, Hans-Meerwein-Str. 4, D-35037 Marburg, Germany
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15
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Wang S, Li HJ, Kuo TS, Shen LC, Liu HJ. Ambiphilic Nature of Dipyrrolylpyridine-Supported Divalent Germanium and Tin Compounds. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00494] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Shuo Wang
- Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 Daxue Road, East District, Hsinchu City, Taiwan 30010
- Department of Applied Chemistry, National Chiao Tung University, 1001 Daxue Road, East District, Hsinchu City, Taiwan 30010
| | - Han-Jung Li
- Material and Chemical Research Laboratories, Industrial Technology Research Institute, 195, Sec. 4, Chung Hsing Road,
Chutung, Hsinchu, Taiwan 31040
| | - Ting-Shen Kuo
- Department of Chemistry, National Taiwan Normal University, Taipei 11677, Taiwan
| | - Li-Ching Shen
- Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 Daxue Road, East District, Hsinchu City, Taiwan 30010
- Department of Applied Chemistry, National Chiao Tung University, 1001 Daxue Road, East District, Hsinchu City, Taiwan 30010
| | - Hsueh-Ju Liu
- Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 Daxue Road, East District, Hsinchu City, Taiwan 30010
- Department of Applied Chemistry, National Chiao Tung University, 1001 Daxue Road, East District, Hsinchu City, Taiwan 30010
- Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
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16
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Hyun SM, Reid KA, Vali SW, Lindahl PA, Powers DC. Cis-Divacant Octahedral Fe(II) in a Dimensionally Reduced Family of 2-(Pyridin-2-yl)pyrrolide Complexes. Inorg Chem 2021; 60:15617-15626. [PMID: 34590844 DOI: 10.1021/acs.inorgchem.1c02240] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Four-coordinate transition-metal complexes can adopt a diverse array of coordination geometries, with square planar and tetrahedral coordination being the most prevalent. Previously, we reported the synthesis of a trinuclear Fe(II) complex, Fe3TPM2, supported by a 3-fold-symmetric 2-pyridylpyrrolide ligand [i.e., tris(5-(pyridin-2-yl)-1H-pyrrol-2-yl)methane] that featured a rare cis-divacant octahedral (CDO) geometry at each Fe(II) center. Here, a series of truncated 2-pyridylpyrrolide ligands are described that support mono- and binuclear Fe(II) complexes that also exhibit CDO geometries. Metalation of the tetradentate ligand bis[5-(pyridin-2-yl)-1H-pyrrol-2-yl]methane (H2BPM) in tetrahydrofuran (THF) results in the binuclear complex Fe2(BPM)2(THF)2 in which both Fe(II) ions are octahedrally coordinated. The coordinated THF solvent ligands are labile: THF dissociation leads to Fe2(BPM)2, which features five-coordinate Fe(II) ions. The Fe-Fe distance in these binuclear complexes can be elongated by ligand methylation. Metalation of bis[5-(6-methylpyridin-2-yl)-1H-pyrrol-2-yl]methane (H2BPMMe) in THF leads to the formation of four-coordinate, CDO Fe(II) centers in Fe(BPMMe)2. Further ligand truncation affords bidentate ligands 2-(1H-pyrrol-2-yl)pyridine (PyrPyrrH) and 2-methyl-6-(1H-pyrrol-2-yl)pyridine (PyrMePyrrH). Metalation of these ligands in THF affords six-coordinate complexes Fe(PyrPyrr)2(THF)2 and Fe(PyrMePyrr)2(THF)2. Dissociation of labile solvent ligands provides access to four-coordinate Fe(II) complexes. Ligand disproportionation at Fe(PyrPyrr)2 results in the formation of Fe(PyrPyrr)3 and Fe(0). Ligand methylation suppresses this disproportionation and enables isolation of Fe(PyrMePyrr)2, which is rigorously CDO. Complete ligand truncation, by separating the 2-pyridylpyrrolide ligands into the constituent monodentate pyridyl and pyrrolide donors, affords Fe(Pyr)2(Pyrr)2 in which Fe(II) is tetrahedrally coordinated. Computational analysis indicates that the potential energy surface that dictates the coordination geometry in this family of four-coordinate complexes is fairly flat in the vicinity of CDO coordination. These synthetic studies provide the structural basis to explore the implications of CDO geometry on Fe-catalyzed reactions.
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Affiliation(s)
- Sung-Min Hyun
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Kaleb A Reid
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Shaik Waseem Vali
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Paul A Lindahl
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - David C Powers
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
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17
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Grünwald A, Anjana SS, Munz D. Terminal Imido Complexes of the Groups 9–11: Electronic Structure and Developments in the Last Decade. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100410] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Annette Grünwald
- Inorganic Chemistry: Coordination Chemistry Saarland University Campus Geb. C4.1 66123 Saarbücken Germany
- Inorganic and General Chemistry Friedrich-Alexander Universität (FAU) Erlangen-Nürnberg Egerlandstr. 1 91058 Erlangen Germany
| | - S. S. Anjana
- Inorganic Chemistry: Coordination Chemistry Saarland University Campus Geb. C4.1 66123 Saarbücken Germany
| | - Dominik Munz
- Inorganic Chemistry: Coordination Chemistry Saarland University Campus Geb. C4.1 66123 Saarbücken Germany
- Inorganic and General Chemistry Friedrich-Alexander Universität (FAU) Erlangen-Nürnberg Egerlandstr. 1 91058 Erlangen Germany
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18
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Richards CA, Rath NP, Neely JM. Iron-Catalyzed Alkyne Carboamination via an Isolable Iron Imide Complex. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00454] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Corey A. Richards
- Department of Chemistry, Saint Louis University, St. Louis, Missouri 63103, United States
| | - Nigam P. Rath
- Department of Chemistry and Biochemistry, University of Missouri—St. Louis, St. Louis, Missouri 63121, United States
| | - Jamie M. Neely
- Department of Chemistry, Saint Louis University, St. Louis, Missouri 63103, United States
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19
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Aguilar-Calderón JR, Fehn D, Sorsche D, Miehlich M, Carroll PJ, Zars E, Meyer K, Mindiola DJ. Redox-Controlled and Reversible N-N Bond Forming and Splitting with an Iron IV Terminal Imido Ligand. Inorg Chem 2021; 60:13091-13100. [PMID: 34375089 DOI: 10.1021/acs.inorgchem.1c01509] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Oxidation of the low-spin FeIV imido complex [{(tBupyrr)2py}Fe═NAd] (1) ((tBupyrr)2py2- = 2,6-bis(3,5-di-tert-butyl-pyrrolyl)pyridine, Ad = 1-adamantyl) with AgOAc or AgNO3 promotes reductive N-N bond coupling of the former imido nitrogen with a pyrrole nitrogen to form the respective ferric hydrazido-like pincer complexes [{(tBupyrrNAd)(tBupyrr)py}Fe(κ2-X)] (X = OAc-, 2OAc; NO3-, 2NO3). Reduction of 2OAc with KC8 cleaves the N-N bond to reform the FeIV imido ligand in 1, whereas acid-mediated demetalation of 2OAc or 2NO3 yields the free hydrazine ligand [(tBupyrrNHAd)(tBupyrrH)py] (3), the latter of which can be used as a direct entry to the iron imido complex when treated with [Fe{N(SiMe3)2}2]. In addition to characterizing these Fe systems, we show how this nitrene transfer strategy can be expanded to Co for the one-step synthesis of Co{(tBu-NHAdpyrr)(tBupyrr)py}] (4) ((tBu-NHAdpyrr)(tBupyrr)py2- = 2-(3-tBu-5-(1-adamantylmethyl-2-methylpropane-2-yl)-pyrrol-2-yl)-6-(3,5-tBu2-pyrrol-2-yl)-pyridine).
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Affiliation(s)
| | - Dominik Fehn
- Inorganic Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
| | - Dieter Sorsche
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Matthias Miehlich
- Inorganic Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
| | - Patrick J Carroll
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Ethan Zars
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Karsten Meyer
- Inorganic Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
| | - Daniel J Mindiola
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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20
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Mao W, Fehn D, Heinemann FW, Scheurer A, Munz D, Meyer K. A Pair of Cobalt(III/IV) Terminal Imido Complexes. Angew Chem Int Ed Engl 2021; 60:16480-16486. [PMID: 33847448 PMCID: PMC8362208 DOI: 10.1002/anie.202103170] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 03/29/2021] [Indexed: 12/16/2022]
Abstract
The reaction of the cobalt(I) complex [(TIMMNmes )CoI ](BPh4 ) (2) (TIMMNmes =tris-[2-(3-mesitylimidazolin-2-ylidene)methyl]amine) with 1-adamantylazide yields the cobalt(III) imido complex [(TIMMNmes )CoIII (NAd)](BPh4 ) (3) with concomitant release of dinitrogen. The N-anchor in diamagnetic 3 features an unusual, planar tertiary amine, which results from repulsive electrostatic interaction with the filled d(z2 )-orbital of the cobalt ion and negative hyperconjugation with the neighboring methylene groups. One-electron oxidation of 3 with [FeCp2 ](OTf) provides access to the rare, high-valent cobalt(IV) imido complex [(TIMMNmes )CoIV (NAd)](OTf)2 (4). Despite a half-life of less than 1 h at room temperature, 4 could be isolated at low temperatures in analytically pure form. Single-crystal X-ray diffractometry and EPR spectroscopy corroborate the molecular structure and the d5 low-spin, S= 1 / 2 , electron configuration. A computational analysis of 4 suggests high covalency within the CoIV =NAd bond with non-negligible spin density located at the imido moiety, which translates into substantial triplet nitrene character.
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Affiliation(s)
- Weiqing Mao
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
| | - Dominik Fehn
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
| | - Frank W. Heinemann
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
| | - Andreas Scheurer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
| | - Dominik Munz
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
- Current address: Saarland UniversityInorganic Chemistry: Coordination ChemistryCampus C4.166123SaarbrückenGermany
| | - Karsten Meyer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
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21
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Hakey BM, Leary DC, Rodriguez JG, Martinez JC, Vaughan NB, Darmon JM, Akhmedov NG, Petersen JL, Dolinar BS, Milsmann C. Effects of 2,6‐Dichlorophenyl Substituents on the Coordination Chemistry of Pyridine Dipyrrolide Iron Complexes. Z Anorg Allg Chem 2021. [DOI: 10.1002/zaac.202100117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Brett M. Hakey
- C. Eugene Bennett Department of Chemistry West Virginia University Morgantown, West Virginia USA
| | - Dylan C. Leary
- C. Eugene Bennett Department of Chemistry West Virginia University Morgantown, West Virginia USA
| | - Jose G. Rodriguez
- C. Eugene Bennett Department of Chemistry West Virginia University Morgantown, West Virginia USA
| | - Jordan C. Martinez
- C. Eugene Bennett Department of Chemistry West Virginia University Morgantown, West Virginia USA
| | - Nicholas B. Vaughan
- C. Eugene Bennett Department of Chemistry West Virginia University Morgantown, West Virginia USA
| | | | - Novruz G. Akhmedov
- C. Eugene Bennett Department of Chemistry West Virginia University Morgantown, West Virginia USA
| | - Jeffrey L. Petersen
- C. Eugene Bennett Department of Chemistry West Virginia University Morgantown, West Virginia USA
| | - Brian S. Dolinar
- C. Eugene Bennett Department of Chemistry West Virginia University Morgantown, West Virginia USA
| | - Carsten Milsmann
- C. Eugene Bennett Department of Chemistry West Virginia University Morgantown, West Virginia USA
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22
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Mao W, Fehn D, Heinemann FW, Scheurer A, Munz D, Meyer K. A Pair of Cobalt(III/IV) Terminal Imido Complexes. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103170] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Weiqing Mao
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Inorganic Chemistry Egerlandstrasse 1 91058 Erlangen Germany
| | - Dominik Fehn
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Inorganic Chemistry Egerlandstrasse 1 91058 Erlangen Germany
| | - Frank W. Heinemann
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Inorganic Chemistry Egerlandstrasse 1 91058 Erlangen Germany
| | - Andreas Scheurer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Inorganic Chemistry Egerlandstrasse 1 91058 Erlangen Germany
| | - Dominik Munz
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Inorganic Chemistry Egerlandstrasse 1 91058 Erlangen Germany
- Current address: Saarland University Inorganic Chemistry: Coordination Chemistry Campus C4.1 66123 Saarbrücken Germany
| | - Karsten Meyer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Inorganic Chemistry Egerlandstrasse 1 91058 Erlangen Germany
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23
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Stennett CR, Fettinger JC, Power PP. Low-Coordinate Iron Chalcogenolates and Their Complexes with Diethyl Ether and Ammonia. Inorg Chem 2021; 60:6712-6720. [PMID: 33848423 DOI: 10.1021/acs.inorgchem.1c00539] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Treatment of Fe{N(SiMe3)2}2 with 2 equiv of the appropriate phenol or thiol affords the dimers {Fe(OC6H2-2,6-But2-4-Me)2}2 (1) and {Fe(OC6H3-2,6-But2)2}2 (2) or the monomeric Fe{SC6H3-2,6-(C6H3-2,6-Pri2)2}2 (3) in moderate to excellent yields. Recrystallization of 1 and 2 from diethyl ether gives the corresponding three-coordinate ether complexes Fe(OC6H3-2,6-But2-4-Me)2(OEt2) (4) and Fe(OC6H3-2,6-But2)2(OEt2) (5). In contrast, no diethyl ether complex is formed by the dithiolate 3. The 1H NMR spectra of 4 and 5 show equilibria between the ether complexes and the base-free dimers. A comparison of these spectra with those of the dimeric 1 and 2 allows an unambiguous assignment of the paramagnetically shifted signals. Treatment of 1 with excess ammonia gives the tetrahedral diammine Fe(OC6H2-2,6-But2-4-Me)2(NH3)2 (6). Ammonia is strongly coordinated in 6, with no apparent loss of ammine ligand either in solution or upon heating under low pressure. In contrast, significantly weaker ammonia coordination is observed when dithiolate 3 is treated with excess ammonia, which gives the diammine Fe{SC6H3-2,6-(2,6-Pri2-C6H3)2}2(NH3)2 (7). Complex 7 readily loses ammonia either in solution or under reduced pressure to give the monoammine complex Fe{SC6H3-2,6-(2,6-Pri2-C6H3)2}2(NH3) (8). The weak binding of ammonia by iron thiolate 7 reflects the likely behavior of the proposed iron-sulfur active site in nitrogenases, where release of ammonia is required to close the catalytic cycle.
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Affiliation(s)
- Cary R Stennett
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
| | - James C Fettinger
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
| | - Philip P Power
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
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Preparation of iron(IV) nitridoferrate Ca 4FeN 4 through azide-mediated oxidation under high-pressure conditions. Nat Commun 2021; 12:571. [PMID: 33495442 PMCID: PMC7835361 DOI: 10.1038/s41467-020-20881-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 12/28/2020] [Indexed: 11/09/2022] Open
Abstract
Transition metal nitrides are an important class of materials with applications as abrasives, semiconductors, superconductors, Li-ion conductors, and thermoelectrics. However, high oxidation states are difficult to attain as the oxidative potential of dinitrogen is limited by its high thermodynamic stability and chemical inertness. Here we present a versatile synthesis route using azide-mediated oxidation under pressure that is used to prepare the highly oxidised ternary nitride Ca4FeN4 containing Fe4+ ions. This nitridometallate features trigonal-planar [FeN3]5− anions with low-spin Fe4+ and antiferromagnetic ordering below a Neel temperature of 25 K, which are characterised by neutron diffraction, 57Fe-Mössbauer and magnetisation measurements. Azide-mediated high-pressure synthesis opens a way to the discovery of highly oxidised nitrides. High-valent metal nitrides are difficult to stabilise due to the high thermodynamic stability and chemical inertness of N2. Here, the authors employ a large volume press to prepare an iron(IV) nitridoferrate Ca4FeIVN4 from Fe2N and Ca3N2 via azide-mediated oxidation under high pressure conditions.
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Martinez JL, Lutz SA, Yang H, Xie J, Telser J, Hoffman BM, Carta V, Pink M, Losovyj Y, Smith JM. Structural and spectroscopic characterization of an Fe(VI) bis(imido) complex. Science 2020; 370:356-359. [PMID: 33060362 DOI: 10.1126/science.abd3054] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 08/31/2020] [Indexed: 11/02/2022]
Abstract
High-valent iron species are key intermediates in oxidative biological processes, but hexavalent complexes apart from the ferrate ion are exceedingly rare. Here, we report the synthesis and structural and spectroscopic characterization of a stable Fe(VI) complex (3) prepared by facile one-electron oxidation of an Fe(V) bis(imido) (2). Single-crystal x-ray diffraction of 2 and 3 revealed four-coordinate Fe centers with an unusual "seesaw" geometry. 57Fe Mössbauer, x-ray photoelectron, x-ray absorption, and electron-nuclear double resonance (ENDOR) spectroscopies, supported by electronic structure calculations, support a low-spin (S = 1/2) d3 Fe(V) configuration in 2 and a diamagnetic (S = 0) d2 Fe(VI) configuration in 3 Their shared seesaw geometry is electronically dictated by a balance of Fe-imido σ- and π-bonding interactions.
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Affiliation(s)
- Jorge L Martinez
- Department of Chemistry, Indiana University, Bloomington, IN 47405, USA
| | - Sean A Lutz
- Department of Chemistry, Indiana University, Bloomington, IN 47405, USA
| | - Hao Yang
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
| | - Jiaze Xie
- Department of Chemistry, University of Chicago, Chicago, IL 60637, USA
| | - Joshua Telser
- Department of Biological, Physical and Health Sciences, Roosevelt University, Chicago, IL 60605, USA
| | - Brian M Hoffman
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
| | - Veronica Carta
- Department of Chemistry, Indiana University, Bloomington, IN 47405, USA
| | - Maren Pink
- Department of Chemistry, Indiana University, Bloomington, IN 47405, USA
| | - Yaroslav Losovyj
- Department of Chemistry, Indiana University, Bloomington, IN 47405, USA
| | - Jeremy M Smith
- Department of Chemistry, Indiana University, Bloomington, IN 47405, USA.
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Coin G, Patra R, Rana S, Biswas JP, Dubourdeaux P, Clémancey M, de Visser SP, Maiti D, Maldivi P, Latour JM. Fe-Catalyzed Aziridination Is Governed by the Electron Affinity of the Active Imido-Iron Species. ACS Catal 2020. [DOI: 10.1021/acscatal.0c01427] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Guillaume Coin
- Univ. Grenoble Alpes, CEA, CNRS, IRIG, LCBM, 38000 Grenoble, France
- Univ. Grenoble Alpes, CEA, CNRS, DCM, 38000 Grenoble, France
| | - Ranjan Patra
- Univ. Grenoble Alpes, CEA, CNRS, IRIG, LCBM, 38000 Grenoble, France
- Univ. Grenoble Alpes, CEA, CNRS, IRIG, DIESE, SYMMES, 38000 Grenoble, France
- Amity Institute of Click Chemistry Research & Studies (AICCRS), Amity University, Sector-125, Noida, India
| | - Sujoy Rana
- Department of Chemistry, University of North Bengal, Raja Rammohunpur, Darjeeling, West Bengal 734013, India
| | | | | | - Martin Clémancey
- Univ. Grenoble Alpes, CEA, CNRS, IRIG, LCBM, 38000 Grenoble, France
| | - Sam P. de Visser
- Manchester Institute of Biotechnology and Department of Chemical Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Debabrata Maiti
- Department of Chemistry, IIT Bombay, Powai, Mumbai 400076, India
| | - Pascale Maldivi
- Univ. Grenoble Alpes, CEA, CNRS, IRIG, DIESE, SYMMES, 38000 Grenoble, France
| | - Jean-Marc Latour
- Univ. Grenoble Alpes, CEA, CNRS, IRIG, LCBM, 38000 Grenoble, France
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Reckziegel A, Pietzonka C, Kraus F, Werncke CG. C-H Bond Activation by an Imido Cobalt(III) and the Resulting Amido Cobalt(II) Complex. Angew Chem Int Ed Engl 2020; 59:8527-8531. [PMID: 32119164 PMCID: PMC7318117 DOI: 10.1002/anie.201914718] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Indexed: 12/31/2022]
Abstract
The 3d-metal mediated nitrene transfer is under intense scrutiny due to its potential as an atom economic and ecologically benign way for the directed amination of (un)functionalised C-H bonds. Here we present the isolation and characterisation of a rare, trigonal imido cobalt(III) complex, which bears a rather long cobalt-imido bond. It can cleanly cleave strong C-H bonds with a bond dissociation energy of up to 92 kcal mol-1 in an intermolecular fashion, unprecedented for imido cobalt complexes. This resulted in the amido cobalt(II) complex [Co(hmds)2 (NHt Bu)]- . Kinetic studies on this reaction revealed an H atom transfer mechanism. Remarkably, the cobalt(II) amide itself is capable of mediating H atom abstraction or stepwise proton/electron transfer depending on the substrate. A cobalt-mediated catalytic application for substrate dehydrogenation using an organo azide is presented.
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Affiliation(s)
- Alexander Reckziegel
- Fachbereich 15/ChemiePhilipps-Universität MarburgHans-Meerwein-Straße 435043MarburgGermany
| | - Clemens Pietzonka
- Fachbereich 15/ChemiePhilipps-Universität MarburgHans-Meerwein-Straße 435043MarburgGermany
| | - Florian Kraus
- Fachbereich 15/ChemiePhilipps-Universität MarburgHans-Meerwein-Straße 435043MarburgGermany
| | - C. Gunnar Werncke
- Fachbereich 15/ChemiePhilipps-Universität MarburgHans-Meerwein-Straße 435043MarburgGermany
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Reactions of a Bis(vinyltrimethylsilane)nickel(0) N-Heterocyclic carbene complex with organic azides. J Organomet Chem 2020. [DOI: 10.1016/j.jorganchem.2020.121195] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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29
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Affiliation(s)
- Anuvab Das
- Department of Chemistry, Texas A&M University, College Station, Texas, USA
| | | | - David C. Powers
- Department of Chemistry, Texas A&M University, College Station, Texas, USA
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30
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Sorsche D, Miehlich ME, Searles K, Gouget G, Zolnhofer EM, Fortier S, Chen CH, Gau M, Carroll PJ, Murray CB, Caulton KG, Khusniyarov MM, Meyer K, Mindiola DJ. Unusual Dinitrogen Binding and Electron Storage in Dinuclear Iron Complexes. J Am Chem Soc 2020; 142:8147-8159. [DOI: 10.1021/jacs.0c01488] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Dieter Sorsche
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Matthias E. Miehlich
- Inorganic Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander University Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Keith Searles
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
- Department of Chemistry and Molecular Structure Center, Indiana University, Bloomington, Indiana 47405, United States
| | - Guillaume Gouget
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Eva M. Zolnhofer
- Inorganic Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander University Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Skye Fortier
- Department of Chemistry and Molecular Structure Center, Indiana University, Bloomington, Indiana 47405, United States
| | - Chun-Hsing Chen
- Department of Chemistry and Molecular Structure Center, Indiana University, Bloomington, Indiana 47405, United States
| | - Michael Gau
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Patrick J. Carroll
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Christopher B. Murray
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Kenneth G. Caulton
- Department of Chemistry and Molecular Structure Center, Indiana University, Bloomington, Indiana 47405, United States
| | - Marat M. Khusniyarov
- Inorganic Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander University Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Karsten Meyer
- Inorganic Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander University Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Daniel J. Mindiola
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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31
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Reckziegel A, Pietzonka C, Kraus F, Werncke CG. C‐H‐Bindungsaktivierung durch einen Imidocobalt(III)‐ und den resultierenden Amidocobalt(II)‐Komplex. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201914718] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Alexander Reckziegel
- Fachbereich 15/Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35043 Marburg Deutschland
| | - Clemens Pietzonka
- Fachbereich 15/Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35043 Marburg Deutschland
| | - Florian Kraus
- Fachbereich 15/Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35043 Marburg Deutschland
| | - C. Gunnar Werncke
- Fachbereich 15/Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35043 Marburg Deutschland
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DeJesus JF, Jenkins DM. A Chiral Macrocyclic Tetra-N-Heterocyclic Carbene Yields an "All Carbene" Iron Alkylidene Complex. Chemistry 2020; 26:1429-1435. [PMID: 31788868 PMCID: PMC7024548 DOI: 10.1002/chem.201905360] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Indexed: 01/12/2023]
Abstract
The first chiral macrocyclic tetra-N-heterocyclic carbene (NHC) ligand has been synthesized. The macrocycle, prepared in high yield and large scale, was ligated onto palladium and iron to give divalent C2 -symmetric square planar complexes. Multinuclear NMR and single crystal X-ray diffraction demonstrated that there are two distinct NHCs on each ligand, due to the bridging chiral cyclohexane. Oxidation of the iron(II) complex with trimethylamine N-oxide yielded a bridging oxo complex. Diazodiphenylmethane reacted with the iron(II) complex at room temperature to give a paramagnetic diazoalkane complex; the same reaction yielded the "all carbene" complex at elevated temperature. Electrochemical measurements support the assignment of the "all carbene" complex being an alkylidene. Notably, the diazoalkane complex can be directly transformed into the alkylidene complex, which had not been previously demonstrated on iron. Finally, a test catalytic reaction with a diazoalkane on the iron(II) complex does not yield the expected cyclopropane, but actually the azine compound.
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Affiliation(s)
- Joseph F DeJesus
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee, 37996, USA
| | - David M Jenkins
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee, 37996, USA
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Hyun SM, Upadhyay A, Das A, Burns CP, Sung S, Beaty JD, Bhuvanesh N, Nippe M, Powers DC. Kinetic versus thermodynamic metalation enables synthesis of isostructural homo- and heterometallic trinuclear clusters. Chem Commun (Camb) 2020; 56:5893-5896. [DOI: 10.1039/d0cc02346a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Temperature-dependent metalation of a new hexadentate enables the selective synthesis of both mononuclear (i.e. kinetic product) and trinuclear (i.e. thermodynamic product) complexes.
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Affiliation(s)
- Sung-Min Hyun
- Department of Chemistry
- Texas A&M University
- College Station
- USA
| | | | - Anuvab Das
- Department of Chemistry
- Texas A&M University
- College Station
- USA
| | - Corey P. Burns
- Department of Chemistry
- Texas A&M University
- College Station
- USA
| | - Siyoung Sung
- Department of Chemistry
- Texas A&M University
- College Station
- USA
| | - Jeremy D. Beaty
- Department of Chemistry
- Texas A&M University
- College Station
- USA
| | | | - Michael Nippe
- Department of Chemistry
- Texas A&M University
- College Station
- USA
| | - David C. Powers
- Department of Chemistry
- Texas A&M University
- College Station
- USA
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34
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Thompson CV, Tonzetich ZJ. Pincer ligands incorporating pyrrolyl units: Versatile platforms for organometallic chemistry and catalysis. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2020. [DOI: 10.1016/bs.adomc.2020.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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35
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Elsby MR, Baker RT. Strategies and mechanisms of metal–ligand cooperativity in first-row transition metal complex catalysts. Chem Soc Rev 2020; 49:8933-8987. [DOI: 10.1039/d0cs00509f] [Citation(s) in RCA: 86] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The use of metal–ligand cooperation (MLC) by transition metal bifunctional catalysts has emerged at the forefront of homogeneous catalysis science.
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Affiliation(s)
- Matthew R. Elsby
- Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation
- University of Ottawa
- Ottawa
- Canada
| | - R. Tom Baker
- Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation
- University of Ottawa
- Ottawa
- Canada
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Sabenya G, Gamba I, Gómez L, Clémancey M, Frisch JR, Klinker EJ, Blondin G, Torelli S, Que L, Martin-Diaconescu V, Latour JM, Lloret-Fillol J, Costas M. Octahedral iron(iv)-tosylimido complexes exhibiting single electron-oxidation reactivity. Chem Sci 2019; 10:9513-9529. [PMID: 32055323 PMCID: PMC6979323 DOI: 10.1039/c9sc02526j] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 08/17/2019] [Indexed: 11/28/2022] Open
Abstract
High valent iron species are very reactive molecules involved in oxidation reactions of relevance to biology and chemical synthesis. Herein we describe iron(iv)-tosylimido complexes [FeIV(NTs)(MePy2tacn)](OTf)2 (1(IV)[double bond, length as m-dash]NTs) and [FeIV(NTs)(Me2(CHPy2)tacn)](OTf)2 (2(IV)[double bond, length as m-dash]NTs), (MePy2tacn = N-methyl-N,N-bis(2-picolyl)-1,4,7-triazacyclononane, and Me2(CHPy2)tacn = 1-(di(2-pyridyl)methyl)-4,7-dimethyl-1,4,7-triazacyclononane, Ts = Tosyl). 1(IV)[double bond, length as m-dash]NTs and 2(IV)[double bond, length as m-dash]NTs are rare examples of octahedral iron(iv)-imido complexes and are isoelectronic analogues of the recently described iron(iv)-oxo complexes [FeIV(O)(L)]2+ (L = MePy2tacn and Me2(CHPy2)tacn, respectively). 1(IV)[double bond, length as m-dash]NTs and 2(IV)[double bond, length as m-dash]NTs are metastable and have been spectroscopically characterized by HR-MS, UV-vis, 1H-NMR, resonance Raman, Mössbauer, and X-ray absorption (XAS) spectroscopy as well as by DFT computational methods. Ferric complexes [FeIII(HNTs)(L)]2+, 1(III)-NHTs (L = MePy2tacn) and 2(III)-NHTs (L = Me2(CHPy2)tacn) have been isolated after the decay of 1(IV)[double bond, length as m-dash]NTs and 2(IV)[double bond, length as m-dash]NTs in solution, spectroscopically characterized, and the molecular structure of [FeIII(HNTs)(MePy2tacn)](SbF6)2 determined by single crystal X-ray diffraction. Reaction of 1(IV)[double bond, length as m-dash]NTs and 2(IV)[double bond, length as m-dash]NTs with different p-substituted thioanisoles results in the transfer of the tosylimido moiety to the sulphur atom producing sulfilimine products. In these reactions, 1(IV)[double bond, length as m-dash]NTs and 2(IV)[double bond, length as m-dash]NTs behave as single electron oxidants and Hammett analyses of reaction rates evidence that tosylimido transfer is more sensitive than oxo transfer to charge effects. In addition, reaction of 1(IV)[double bond, length as m-dash]NTs and 2(IV)[double bond, length as m-dash]NTs with hydrocarbons containing weak C-H bonds results in the formation of 1(III)-NHTs and 2(III)-NHTs respectively, along with the oxidized substrate. Kinetic analyses indicate that reactions proceed via a mechanistically unusual HAT reaction, where an association complex precedes hydrogen abstraction.
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Affiliation(s)
- Gerard Sabenya
- Institut de Química Computacional i Catàlisi (IQCC) , Departament de Química , Universitat de Girona , Campus Montilivi , E17071 Girona , Spain .
| | - Ilaria Gamba
- Institut de Química Computacional i Catàlisi (IQCC) , Departament de Química , Universitat de Girona , Campus Montilivi , E17071 Girona , Spain .
| | - Laura Gómez
- Institut de Química Computacional i Catàlisi (IQCC) , Departament de Química , Universitat de Girona , Campus Montilivi , E17071 Girona , Spain .
| | - Martin Clémancey
- Univ. Grenoble-Alpes , CNRS , CEA , IRIG , DIESE , CBM , Grenoble 38000 , France
| | - Jonathan R Frisch
- Department of Chemistry , University of Minnesota , Pleasant Str 207 , Minneapolis , Minnesota , USA
| | - Eric J Klinker
- Department of Chemistry , University of Minnesota , Pleasant Str 207 , Minneapolis , Minnesota , USA
| | - Geneviève Blondin
- Univ. Grenoble-Alpes , CNRS , CEA , IRIG , DIESE , CBM , Grenoble 38000 , France
| | - Stéphane Torelli
- Univ. Grenoble-Alpes , CNRS , CEA , IRIG , DIESE , CBM , Grenoble 38000 , France
| | - Lawrence Que
- Department of Chemistry , University of Minnesota , Pleasant Str 207 , Minneapolis , Minnesota , USA
| | - Vlad Martin-Diaconescu
- Institut de Química Computacional i Catàlisi (IQCC) , Departament de Química , Universitat de Girona , Campus Montilivi , E17071 Girona , Spain .
- Institute of Chemical Research of Catalonia (ICIQ) , The Barcelona Institute of Science and Technology , Avinguda Països Catalans 16 , 43007 Tarragona , Spain .
| | - Jean-Marc Latour
- Univ. Grenoble-Alpes , CNRS , CEA , IRIG , DIESE , CBM , Grenoble 38000 , France
| | - Julio Lloret-Fillol
- Institut de Química Computacional i Catàlisi (IQCC) , Departament de Química , Universitat de Girona , Campus Montilivi , E17071 Girona , Spain .
- 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
| | - Miquel Costas
- Institut de Química Computacional i Catàlisi (IQCC) , Departament de Química , Universitat de Girona , Campus Montilivi , E17071 Girona , Spain .
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Baek Y, Hennessy ET, Betley TA. Direct Manipulation of Metal Imido Geometry: Key Principles to Enhance C-H Amination Efficacy. J Am Chem Soc 2019; 141:16944-16953. [PMID: 31550162 DOI: 10.1021/jacs.9b09015] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We report the catalytic C-H amination mediated by an isolable CoIII imido complex (TrL)Co(NR) supported by a sterically demanding dipyrromethene ligand (TrL = 5-mesityl-1,9-(trityl)dipyrrin). Metalation of (TrL)Li with CoCl2 in THF afforded a high-spin (S = 3/2) three-coordinate complex (TrL)CoCl. Chemical reduction of (TrL)CoCl with potassium graphite yielded the high-spin (S = 1) CoI synthon (TrL)Co which is stabilized through an intramolecular η6-arene interaction. Treatment of (TrL)Co with a stoichiometric amount of 1-azidoadamantane (AdN3) furnished a three-coordinate, diamagnetic CoIII imide (TrL)Co(NAd) as confirmed by single-crystal X-ray diffraction, revealing a rare trigonal pyramidal geometry with an acute Co-Nimido-C angle 145.0(3)°. Exposure of 1-10 mol % of (TrL)Co to linear alkyl azides (RN3) resulted in catalytic formation of substituted N-heterocycles via intramolecular C-H amination of a range of C-H bonds, including primary C-H bonds. The mechanism of the C-N bond formation was probed via initial rate kinetic analysis and kinetic isotope effect experiments [kH/kD = 38.4(1)], suggesting a stepwise H-atom abstraction followed by radical recombination. In contrast to the previously reported C-H amination mediated by (ArL)Co(NR) (ArL = 5-mesityl-1,9-(2,4,6-Ph3C6H2)dipyrrin), (TrL)Co(NR) displays enhanced yields and rates of C-H amination without the aid of a cocatalyst, and no catalyst degradation to a tetrazene species was observed, as further supported by the pyridine inhibition effect on the rate of C-H amination. Furthermore, (TrL)Co(NAd) exhibits an extremely low one-electron reduction potential (E°red = -1.98 V vs [Cp2Fe]+/0) indicating that the highly basic terminal imido unit contributes to the driving force for H-atom abstraction.
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Affiliation(s)
- Yunjung Baek
- Department of Chemistry and Chemical Biology , Harvard University , 12 Oxford Street , Cambridge , Massachusetts 02138 , United States
| | - Elisabeth T Hennessy
- Department of Chemistry and Chemical Biology , Harvard University , 12 Oxford Street , Cambridge , Massachusetts 02138 , United States
| | - Theodore A Betley
- Department of Chemistry and Chemical Biology , Harvard University , 12 Oxford Street , Cambridge , Massachusetts 02138 , United States
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38
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Turner ZR. Bismuth Pyridine Dipyrrolide Complexes: a Transient Bi(II) Species Which Ring Opens Cyclic Ethers. Inorg Chem 2019; 58:14212-14227. [DOI: 10.1021/acs.inorgchem.9b02314] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Zoë R. Turner
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford OX1 3TA, United Kingdom
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39
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Hakey BM, Darmon JM, Akhmedov NG, Petersen JL, Milsmann C. Reactivity of Pyridine Dipyrrolide Iron(II) Complexes with Organic Azides: C–H Amination and Iron Tetrazene Formation. Inorg Chem 2019; 58:11028-11042. [PMID: 31364852 DOI: 10.1021/acs.inorgchem.9b01560] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Brett M. Hakey
- C. Eugene Bennett Department of Chemistry, West Virginia University, 100 Prospect Street, Morgantown, West Virginia 26506, United States
| | - Jonathan M. Darmon
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Novruz G. Akhmedov
- C. Eugene Bennett Department of Chemistry, West Virginia University, 100 Prospect Street, Morgantown, West Virginia 26506, United States
| | - Jeffrey L. Petersen
- C. Eugene Bennett Department of Chemistry, West Virginia University, 100 Prospect Street, Morgantown, West Virginia 26506, United States
| | - Carsten Milsmann
- C. Eugene Bennett Department of Chemistry, West Virginia University, 100 Prospect Street, Morgantown, West Virginia 26506, United States
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40
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Isbill SB, Chandrachud PP, Kern JL, Jenkins DM, Roy S. Elucidation of the Reaction Mechanism of C 2 + N 1 Aziridination from Tetracarbene Iron Catalysts. ACS Catal 2019; 9:6223-6233. [PMID: 31534826 DOI: 10.1021/acscatal.9b01306] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A combined computational and experimental study was undertaken to elucidate the mechanism of catalytic C2 + N1 aziridination supported by tetracarbene iron complexes. Three specific aspects of the catalytic cycle were addressed. First, how do organic azides react with different iron catalysts and why are alkyl azides ineffective for some catalysts? Computation of the catalytic pathway using density functional theory (DFT) revealed that an alkyl azide needs to overcome a higher activation barrier than an aryl azide to form an iron imide, and the activation barrier with the first-generation catalyst is higher than the activation barrier with the second-generation variant. Second, does the aziridination from the imide complex proceed through an open-chain radical intermediate that can change stereochemistry or, instead, via an azametallacyclobutane intermediate that retains stereochemistry? DFT calculations show that the formation of aziridine proceeds via the open-chain radical intermediate, which qualitatively explains the formation of both aziridine diastereomers as seen in experiments. Third, how can the formation of the side product, a metallotetrazene, be prevented, which would improve the yield of aziridine at lower alkene loading? DFT and experimental results demonstrate that sterically bulky organic azides prohibit formation of the metallotetrazene and, thus, allow lower alkene loading for effective catalysis. These multiple insights of different aspects of the catalytic cycle are critical for developing improved catalysts for C2 + N1 aziridination.
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Affiliation(s)
- Sara B. Isbill
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Preeti P. Chandrachud
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Jesse L. Kern
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - David M. Jenkins
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Sharani Roy
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
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41
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Anneser MR, Elpitiya GR, Townsend J, Johnson EJ, Powers XB, DeJesus JF, Vogiatzis KD, Jenkins DM. Unprecedented Five‐Coordinate Iron(IV) Imides Generate Divergent Spin States Based on the Imide R‐Groups. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201903132] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Markus R. Anneser
- Department of Chemistry University of Tennessee Knoxville TN 37996 USA
| | - Gaya R. Elpitiya
- Department of Chemistry University of Tennessee Knoxville TN 37996 USA
| | - Jacob Townsend
- Department of Chemistry University of Tennessee Knoxville TN 37996 USA
| | - Elizabeth J. Johnson
- Department of Chemistry and Chemical Biology Harvard University Cambridge MA 02138 USA
| | - Xian B. Powers
- Department of Chemistry University of Tennessee Knoxville TN 37996 USA
| | - Joseph F. DeJesus
- Department of Chemistry University of Tennessee Knoxville TN 37996 USA
| | | | - David M. Jenkins
- Department of Chemistry University of Tennessee Knoxville TN 37996 USA
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42
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Anneser MR, Elpitiya GR, Townsend J, Johnson EJ, Powers XB, DeJesus JF, Vogiatzis KD, Jenkins DM. Unprecedented Five-Coordinate Iron(IV) Imides Generate Divergent Spin States Based on the Imide R-Groups. Angew Chem Int Ed Engl 2019; 58:8115-8118. [PMID: 30974012 PMCID: PMC6546507 DOI: 10.1002/anie.201903132] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Indexed: 01/05/2023]
Abstract
Three five-coordinate iron(IV) imide complexes have been synthesized and characterized. These novel structures have disparate spin states on the iron as a function of the R-group attached to the imide, with alkyl groups leading to low-spin diamagnetic (S=0) complexes and an aryl group leading to an intermediate-spin (S=1) complex. The different spin states lead to significant differences in the bonding about the iron center as well as the spectroscopic properties of these complexes. Mössbauer spectroscopy confirmed that all three imide complexes are in the iron(IV) oxidation state. The combination of diamagnetism and 15 N labeling allowed for the first 15 N NMR resonance recorded on an iron imide. Multi-reference calculations corroborate the experimental structural findings and suggest how the bonding is distinctly different on the imide ligand between the two spin states.
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Affiliation(s)
- Markus R Anneser
- Department of Chemistry, University of Tennessee, Knoxville, TN, 37996, USA
| | - Gaya R Elpitiya
- Department of Chemistry, University of Tennessee, Knoxville, TN, 37996, USA
| | - Jacob Townsend
- Department of Chemistry, University of Tennessee, Knoxville, TN, 37996, USA
| | - Elizabeth J Johnson
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Xian B Powers
- Department of Chemistry, University of Tennessee, Knoxville, TN, 37996, USA
| | - Joseph F DeJesus
- Department of Chemistry, University of Tennessee, Knoxville, TN, 37996, USA
| | | | - David M Jenkins
- Department of Chemistry, University of Tennessee, Knoxville, TN, 37996, USA
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43
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Cheng J, Liu J, Leng X, Lohmiller T, Schnegg A, Bill E, Ye S, Deng L. A Two-Coordinate Iron(II) Imido Complex with NHC Ligation: Synthesis, Characterization, and Its Diversified Reactivity of Nitrene Transfer and C-H Bond Activation. Inorg Chem 2019; 58:7634-7644. [PMID: 31083985 PMCID: PMC6750749 DOI: 10.1021/acs.inorgchem.9b01147] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Iron
terminal imido species are typically implicated as reaction intermediates
in iron-catalyzed transformations. While a large body of work has
been devoted to mid- and high-valent iron imidos, to date the chemistry
of iron(II) imidos has remained largely unexplored due to the difficulty
in accessing them. Herein, we present a study on the two-coordinate
iron(II) imido complex [(IPr)Fe(NArTrip)] (3; IPr = 1,3-bis(2′,6′-diisopropylphenyl)imidazol-2-ylidene;
ArTrip = 2,6-bis(2′,4′,6′-triisopropylphenyl)phenyl)
prepared from the reaction of an iron(0) complex with the bulky azide
ArTripN3. Spectroscopic investigations in combination
with DFT calculations established a high-spin S =
2 ground spin state for 3, consistent with its long Fe–N
multiple bond of 1.715(2) Å revealed by X-ray diffraction analysis.
Complex 3 exhibits unusual activity of nitrene transfer
and C–H bond activation in comparison to the reported iron
imido complexes. Specifically, the reactions of 3 with
CH2=CHArCF3, an electron-deficient alkene,
and CO, a strong π acid, readily afford nitrene transfer products,
ArCF3CH=CHNHArTrip and ArTripNCO, respectively, yet no similar reaction occurs when 3 is treated with electron-rich alkenes and PMe3. Moreover, 3 is inert toward the weak C(sp3)–H bonds
in 1,4-cyclohexadiene, THF, and toluene, whereas it can cleave the
stronger C(sp)–H bond in p-trifluoromethylphenylacetylene
to form an iron(II) amido alkynyl complex. Interestingly, intramolecular
C(sp3)–H bond functionalization was observed by
adding (p-Tol)2CN2 to 3. The unique reactivity of 3 is attributed to
its low-coordinate nature and the high negative charge population
on the imido N atom, which render its iron–imido unit nucleophilic
in nature. The two-coordinate iron(II)
imido complex (IPr)Fe(NArTrip) (3) exhibits
a high-spin ground state (S = 2) and was found to
be reactive toward electron-deficient alkene, diazo compounds, terminal
alkyne, et al., in which diversified reactivities of nitrene transfer,
C−H bond activation, and C−N bond formation have been
observed. The reactivity pattern reflects the nucleophilic nature
of the imido moiety of the high-spin iron(II) complex.
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Affiliation(s)
- Jun Cheng
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis , Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , People's Republic of China
| | - Jian Liu
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis , Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , People's Republic of China
| | - Xuebing Leng
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis , Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , People's Republic of China
| | - Thomas Lohmiller
- Berlin Joint EPR Lab , Helmholtz-Zentrum Berlin für Materialien und Energie , Berlin , Germany
| | - Alexander Schnegg
- Max-Planck-Institut für Chemische Energiekonversion , Mülheim an der Ruhr D-45470 , Germany
| | - Eckhard Bill
- Max-Planck-Institut für Chemische Energiekonversion , Mülheim an der Ruhr D-45470 , Germany
| | - Shengfa Ye
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1 , Mülheim an der Ruhr D-45470 , Germany
| | - Liang Deng
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis , Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , People's Republic of China
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44
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Chen JJ, Xu YC, Gan ZL, Peng X, Yi XY. Zinc Complexes with Tridentate Pyridyl-Pyrrole Ligands and their Use as Catalysts in CO2
Fixation into Cyclic Carbonates. Eur J Inorg Chem 2019. [DOI: 10.1002/ejic.201801246] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Jing-Jing Chen
- College of Chemistry and Chemical Engineering; Central South University; 410083 Changsha Hunan P.R. China
| | - Yao-Chun Xu
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province; College of Optoelectronic Engineering; Shenzhen University; 518060 Shenzhen China
| | - Zhi-Liang Gan
- College of Chemistry and Chemical Engineering; Central South University; 410083 Changsha Hunan P.R. China
| | - Xiao Peng
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province; College of Optoelectronic Engineering; Shenzhen University; 518060 Shenzhen China
| | - Xiao-Yi Yi
- College of Chemistry and Chemical Engineering; Central South University; 410083 Changsha Hunan P.R. China
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45
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Anderson CM, Aboelenen AM, Jensen MP. Competitive Intramolecular Amination as a Clock for Iron-Catalyzed Nitrene Transfer. Inorg Chem 2019; 58:1107-1119. [DOI: 10.1021/acs.inorgchem.8b02284] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Caitlin M. Anderson
- Department of Chemistry and Biochemistry, Ohio University, Athens, Ohio 45701, United States
| | - Ahmed M. Aboelenen
- Department of Chemistry and Biochemistry, Ohio University, Athens, Ohio 45701, United States
| | - Michael P. Jensen
- Department of Chemistry and Biochemistry, Ohio University, Athens, Ohio 45701, United States
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46
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Hakey BM, Darmon JM, Zhang Y, Petersen JL, Milsmann C. Synthesis and Electronic Structure of Neutral Square-Planar High-Spin Iron(II) Complexes Supported by a Dianionic Pincer Ligand. Inorg Chem 2019; 58:1252-1266. [PMID: 30608668 DOI: 10.1021/acs.inorgchem.8b02730] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Two square-planar high-spin FeII complexes bearing a dianionic pyridine dipyrrolate pincer ligand and a diethyl ether or tetrahydrofuran ligand were synthesized and structurally characterized, and their electronic structures were elucidated by a combined spectroscopic and computational approach. In contrast to previous examples, the S = 2 ground states of these square-planar FeII complexes do not require an overall anionic charge of the compounds or incorporation of alkali metal cations. The tetrahydrofuran complex exhibits an equilibrium between four- and five-coordinate species in solution, which was supported by 1H NMR and 57Fe Mössbauer spectroscopy and comparison to a structurally characterized five-coordinate pyridine dipyrrolate iron bis-pyridine adduct. A detailed computational analysis of the electronic structures of the four- and five-coordinate species via density functional theory provides insight into the origins of the unusual ground state configurations for FeII in a square-planar ligand field and explains the associated characteristic spectroscopic parameters.
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Affiliation(s)
- Brett M Hakey
- C. Eugene Bennett Department of Chemistry , West Virginia University , 100 Prospect Street , Morgantown , West Virginia 26506 , United States
| | - Jonathan M Darmon
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | - Yu Zhang
- C. Eugene Bennett Department of Chemistry , West Virginia University , 100 Prospect Street , Morgantown , West Virginia 26506 , United States
| | - Jeffrey L Petersen
- C. Eugene Bennett Department of Chemistry , West Virginia University , 100 Prospect Street , Morgantown , West Virginia 26506 , United States
| | - Carsten Milsmann
- C. Eugene Bennett Department of Chemistry , West Virginia University , 100 Prospect Street , Morgantown , West Virginia 26506 , United States
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47
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Flores JA, Andino JG, Lord RL, Wolfe RJ, Park H, Pink M, Telser J, Caulton KG. Probing Redox Noninnocence of Copper and Zinc Bis‐pyridylpyrrolides. Eur J Inorg Chem 2018. [DOI: 10.1002/ejic.201800935] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jaime A. Flores
- Department of Chemistry Indiana University 800 East Kirkwood Avenue 47405 USA Bloomington Indiana47405 USA
| | - José G. Andino
- Department of Chemistry Indiana University 800 East Kirkwood Avenue 47405 USA Bloomington Indiana47405 USA
| | - Richard L. Lord
- Department of Chemistry Grand Valley State University 49401 Allendale Michigan USA
| | - Robert J. Wolfe
- Department of Chemistry Indiana University 800 East Kirkwood Avenue 47405 USA Bloomington Indiana47405 USA
| | - Hyunsoo Park
- Department of Chemistry Indiana University 800 East Kirkwood Avenue 47405 USA Bloomington Indiana47405 USA
| | - Maren Pink
- Department of Chemistry Indiana University 800 East Kirkwood Avenue 47405 USA Bloomington Indiana47405 USA
| | - Joshua Telser
- Department of Biological Physical and Health Sciences Roosevelt University 430 South Michigan Avenue 60605 Chicago Illinois USA
| | - Kenneth G. Caulton
- Department of Chemistry Indiana University 800 East Kirkwood Avenue 47405 USA Bloomington Indiana47405 USA
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48
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McPherson JN, Das B, Colbran SB. Tridentate pyridine–pyrrolide chelate ligands: An under-appreciated ligand set with an immensely promising coordination chemistry. Coord Chem Rev 2018. [DOI: 10.1016/j.ccr.2018.01.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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49
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Wang P, Deng L. Recent Advances in Iron-Catalyzed C-H Bond AminationviaIron Imido Intermediate. CHINESE J CHEM 2018. [DOI: 10.1002/cjoc.201800427] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Peng Wang
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences; 345Lingling Road, Shanghai 200032 China
| | - Liang Deng
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences; 345Lingling Road, Shanghai 200032 China
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50
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Yadav S, Singh A, Rashid N, Ghotia M, Roy TK, Ingole PP, Ray S, Mobin SM, Dash C. Phosphine-Free Bis(Pyrrolyl)pyridine Based NNN-Pincer Palladium(II) Complexes as Efficient Catalysts for Suzuki-Miyaura Cross-Coupling Reactions of Aryl Bromides in Aqueous Medium. ChemistrySelect 2018. [DOI: 10.1002/slct.201801647] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Seema Yadav
- Department of Chemistry; School of Chemical Sciences and Pharmacy; Central University of Rajasthan, Bandarsindri; India
| | - Ajeet Singh
- Department of Chemistry; Indian Institute of Technology (IIT) Indore, Simrol; Khandwa Road Indore - 453552 India
| | - Nusrat Rashid
- Department of Chemistry; Indian Institute of Technology, Delhi, Hauz Khas; New Delhi 110016 India
| | - Maheshwari Ghotia
- Department of Chemistry; School of Chemical Sciences and Pharmacy; Central University of Rajasthan, Bandarsindri; India
| | - Tapta Kanchan Roy
- Department of Chemistry and Chemical Sciences; Central University of Jammu; Jammu-180001 India
| | - Pravin P. Ingole
- Department of Chemistry; Indian Institute of Technology, Delhi, Hauz Khas; New Delhi 110016 India
| | - Sriparna Ray
- Department of Chemistry; School of Basic Sciences; Manipal University; Jaipur-303007 India
| | - Shaikh M. Mobin
- Department of Chemistry; Indian Institute of Technology (IIT) Indore, Simrol; Khandwa Road Indore - 453552 India
| | - Chandrakanta Dash
- Department of Chemistry; School of Chemical Sciences and Pharmacy; Central University of Rajasthan, Bandarsindri; India
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