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Wang Y, Zhou Y, Sun W, Wang X, Yao J, Li H. Identifying Radical Pathways for Cu(I)/Cu(II) Relay Catalyzed Oxygenation via Online Coupled EPR/UV-Vis/Near-IR Monitoring. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2402890. [PMID: 38810102 PMCID: PMC11304242 DOI: 10.1002/advs.202402890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 05/11/2024] [Indexed: 05/31/2024]
Abstract
Copper-catalyzed C─H oxygenation has drawn considerable attention in mechanistic studies. However, a comprehensive investigation combining radical pathways with a metal-catalytic cycle is challenged by the intricate organic radicals and metallic intermediates. Herein, an online coupled EPR/UV-vis/near-IR detecting method is developed to simultaneously monitor both reactive radical species and copper complex intermediates during the reaction. Focusing on copper-catalyzed phenol oxygenation with cumene hydroperoxide, the short-lived alkylperoxyl radical (EPR signal at g = 2.0143) as well as the unexpected square planar Cu(II)-alkoxyl radical complex (near-IR signal at 833 nm) are unveiled during the reaction, in addition to the observable phenoxyl radical in EPR, quinone product in UV-vis, and Cu(II) center in EPR. With a comprehensive picture of diverse intermediates evolving over the same timeline, a novel Cu(I)/Cu(II) proposed relay-catalyzed sequential radical pathway. In this sequence, Cu(II) activates hydroperoxide through Cu(II)-OOR into the alkylperoxide radical, while the reaction between Cu(I) and hydroperoxide leads to Cu(II)(•OR)OH with high H-atom abstracting activity. These results provide a thorough understanding of the Cu(I)/Cu(II) relay catalysis for phenol oxygenation, setting the stage for mechanistic investigations into intricate radical reactions promoted by metallic complexes.
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Affiliation(s)
- Yongtao Wang
- Department of ChemistryZhejiang University866 Yuhangtang RdHangzhou310058China
- Center of Chemistry for Frontier TechnologiesZJU‐NHU United R&D CenterZhejiang University866 Yuhangtang RdHangzhou310058China
| | - Yujia Zhou
- Department of ChemistryZhejiang University866 Yuhangtang RdHangzhou310058China
| | - Wenjing Sun
- Department of ChemistryZhejiang University866 Yuhangtang RdHangzhou310058China
| | - Xinyu Wang
- Department of ChemistryZhejiang University866 Yuhangtang RdHangzhou310058China
| | - Jia Yao
- Department of ChemistryZhejiang University866 Yuhangtang RdHangzhou310058China
- Center of Chemistry for Frontier TechnologiesZJU‐NHU United R&D CenterZhejiang University866 Yuhangtang RdHangzhou310058China
| | - Haoran Li
- Department of ChemistryZhejiang University866 Yuhangtang RdHangzhou310058China
- Center of Chemistry for Frontier TechnologiesZJU‐NHU United R&D CenterZhejiang University866 Yuhangtang RdHangzhou310058China
- State Key Laboratory of Chemical Engineering and College of Chemical and Biological EngineeringZhejiang University866 Yuhangtang RdHangzhou310058China
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Zhang J, Lee YM, Seo MS, Nilajakar M, Fukuzumi S, Nam W. A Contrasting Effect of Acid in Electron Transfer, Oxygen Atom Transfer, and Hydrogen Atom Transfer Reactions of a Nickel(III) Complex. Inorg Chem 2022; 61:19735-19747. [PMID: 36445726 DOI: 10.1021/acs.inorgchem.2c02504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
There have been many examples of the accelerating effects of acids in electron transfer (ET), oxygen atom transfer (OAT), and hydrogen atom transfer (HAT) reactions. Herein, we report a contrasting effect of acids in the ET, OAT, and HAT reactions of a nickel(III) complex, [NiIII(PaPy3*)]2+ (1) in acetone/CH3CN (v/v 19:1). 1 was synthesized by reacting [NiII(PaPy3*)]+ (2) with magic blue or iodosylbenzene in the absence or presence of triflic acid (HOTf), respectively. Sulfoxidation of thioanisole by 1 and H2O occurred in the presence of HOTf, and the reaction rate increased proportionally with increasing concentration of HOTf ([HOTf]). The rate of ET from diacetylferrocene to 1 also increased linearly with increasing [HOTf]. In contrast, HAT from 9,10-dihydroanthracene (DHA) to 1 slowed down with increasing [HOTf], exhibiting an inversely proportional relation to [HOTf]. The accelerating effect of HOTf in the ET and OAT reactions was ascribed to the binding of H+ to the PaPy3* ligand of 2; the one-electron reduction potential (Ered) of 1 was positively shifted with increasing [HOTf]. Such a positive shift in the Ered value resulted in accelerating the ET and OAT reactions that proceeded via the rate-determining ET step. On the other hand, the decelerating effect of HOTf on HAT from DHA to 1 resulted from the inhibition of proton transfer from DHA•+ to 2 due to the binding of H+ to the PaPy3* ligand of 2. The ET reactions of 1 in the absence and presence of HOTf were well analyzed in light of the Marcus theory of ET in comparison with the HAT reactions.
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Affiliation(s)
- Jisheng Zhang
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Yong-Min Lee
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Mi Sook Seo
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Madhuri Nilajakar
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Shunichi Fukuzumi
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Wonwoo Nam
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
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3
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Cypcar AD, Kerr TA, Yang JY. Thermochemical Studies of Nickel Hydride Complexes with Cationic Ligands in Aqueous and Organic Solvents. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Andrew D. Cypcar
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Tyler A. Kerr
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Jenny Y. Yang
- Department of Chemistry, University of California, Irvine, California 92697, United States
- Physical Sciences Division, Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
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4
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Engbers S, Leach IF, Havenith RWA, Klein JEMN. Homolytic X‐H Bond Cleavage at a Gold(III) Hydroxide: Insights into One‐Electron Events at Gold. Chemistry 2022; 28:e202200599. [PMID: 35506505 PMCID: PMC9401072 DOI: 10.1002/chem.202200599] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Indexed: 11/17/2022]
Abstract
C(sp3)‐H and O−H bond breaking steps in the oxidation of 1,4‐cyclohexadiene and phenol by a Au(III)‐OH complex were studied computationally. The analysis reveals that for both types of bonds the initial X−H cleavage step proceeds via concerted proton coupled electron transfer (cPCET), reflecting electron transfer from the substrate directly to the Au(III) centre and proton transfer to the Au‐bound oxygen. This mechanistic picture is distinct from the analogous formal Cu(III)‐OH complexes studied by the Tolman group (J. Am. Chem. Soc. 2019, 141, 17236–17244), which proceed via hydrogen atom transfer (HAT) for C−H bonds and cPCET for O−H bonds. Hence, care should be taken when transferring concepts between Cu−OH and Au−OH species. Furthermore, the ability of Au−OH complexes to perform cPCET suggests further possibilities for one‐electron chemistry at the Au centre, for which only limited examples exist.
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Affiliation(s)
- Silène Engbers
- Molecular Inorganic Chemistry Stratingh Institute for Chemistry Faculty of Science and Engineering University of Groningen Nijenborgh 4 9747 AG Groningen (The Netherlands
| | - Isaac F. Leach
- Molecular Inorganic Chemistry Stratingh Institute for Chemistry Faculty of Science and Engineering University of Groningen Nijenborgh 4 9747 AG Groningen (The Netherlands
- Zernike Institute for Advanced Materials Faculty of Science and Engineering University of Groningen Nijenborgh 4 9747 AG Groningen (The Netherlands
| | - Remco W. A. Havenith
- Molecular Inorganic Chemistry Stratingh Institute for Chemistry Faculty of Science and Engineering University of Groningen Nijenborgh 4 9747 AG Groningen (The Netherlands
- Zernike Institute for Advanced Materials Faculty of Science and Engineering University of Groningen Nijenborgh 4 9747 AG Groningen (The Netherlands
- Ghent Quantum Chemistry Group Department of Chemistry Ghent University Ghent 9000 Gent Belgium
| | - Johannes E. M. N. Klein
- Molecular Inorganic Chemistry Stratingh Institute for Chemistry Faculty of Science and Engineering University of Groningen Nijenborgh 4 9747 AG Groningen (The Netherlands
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5
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Weberg AB, Murphy RP, Tomson NC. Oriented internal electrostatic fields: an emerging design element in coordination chemistry and catalysis. Chem Sci 2022; 13:5432-5446. [PMID: 35694353 PMCID: PMC9116365 DOI: 10.1039/d2sc01715f] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 04/19/2022] [Indexed: 11/21/2022] Open
Abstract
The power of oriented electrostatic fields (ESFs) to influence chemical bonding and reactivity is a phenomenon of rapidly growing interest. The presence of strong ESFs has recently been implicated as one of the most significant contributors to the activity of select enzymes, wherein alignment of a substrate's changing dipole moment with a strong, local electrostatic field has been shown to be responsible for the majority of the enzymatic rate enhancement. Outside of enzymology, researchers have studied the impacts of "internal" electrostatic fields via the addition of ionic salts to reactions and the incorporation of charged functional groups into organic molecules (both experimentally and computationally), and "externally" via the implementation of bulk fields between electrode plates. Incorporation of charged moieties into homogeneous inorganic complexes to generate internal ESFs represents an area of high potential for novel catalyst design. This field has only begun to materialize within the past 10 years but could be an area of significant impact moving forward, since it provides a means for tuning the properties of molecular complexes via a method that is orthogonal to traditional strategies, thereby providing possibilities for improved catalytic conditions and novel reactivity. In this perspective, we highlight recent developments in this area and offer insights, obtained from our own research, on the challenges and future directions of this emerging field of research.
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Affiliation(s)
- Alexander B Weberg
- R, oy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 S. 34th Street Philadelphia Pennsylvania 19104 USA
| | - Ryan P Murphy
- R, oy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 S. 34th Street Philadelphia Pennsylvania 19104 USA
| | - Neil C Tomson
- R, oy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 S. 34th Street Philadelphia Pennsylvania 19104 USA
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6
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Kelty ML, McNeece AJ, Kurutz JW, Filatov AS, Anderson JS. Electrostatic vs. inductive effects in phosphine ligand donor properties and reactivity. Chem Sci 2022; 13:4377-4387. [PMID: 35509471 PMCID: PMC9007067 DOI: 10.1039/d1sc04277g] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 03/15/2022] [Indexed: 11/21/2022] Open
Abstract
Enhanced rates and selectivity in enzymes are enabled in part by precisely tuned electric fields within active sites. Analogously, the use of charged groups to leverage electrostatics in molecular systems is a promising strategy to tune reactivity. However, separation of the through space and through bond effects of charged functional groups is a long standing challenge that limits the rational application of electric fields in molecular systems. To address this challenge we developed a method using the phosphorus selenium coupling value (J P-Se) of anionic phosphine selenides to quantify the electrostatic contribution of the borate moiety to donor strength. In this analysis we report the synthesis of a novel anionic phosphine, PPh2CH2BF3K, the corresponding tetraphenyl phosphonium and tetraethyl ammonium selenides [PPh4][SePPh2CH2BF3] and [TEA][SePPh2CH2BF3], and the Rh carbonyl complex [PPh4][Rh(acac)(CO)(PPh2(CH2BF3))]. Solvent-dependent changes in J P-Se were fit using Coulomb's law and support up to an 80% electrostatic contribution to the increase in donor strength of [PPh4][SePPh2CH2BF3] relative to SePPh2Et, while controls with [TEA][SePPh2CH2BF3] exclude convoluting ion pairing effects. Calculations using explicit solvation or point charges effectively replicate the experimental data. This J P-Se method was extended to [PPh4][SePPh2(2-BF3Ph)] and likewise estimates up to a 70% electrostatic contribution to the increase in donor strength relative to SePPh3. The use of PPh2CH2BF3K also accelerates C-F oxidative addition reactivity with Ni(COD)2 by an order of magnitude in comparison to the comparatively donating neutral phosphines PEt3 and PCy3. This enhanced reactivity prompted the investigation of catalytic fluoroarene C-F borylation, with improved yields observed for less fluorinated arenes. These results demonstrate that covalently bound charged functionalities can exert a significant electrostatic influence under common solution phase reaction conditions and experimentally validate theoretical predictions regarding electrostatic effects in reactivity.
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Affiliation(s)
- Margaret L Kelty
- Department of Chemistry, University of Chicago 929 E 57th St Chicago IL 60637 USA
| | - Andrew J McNeece
- Department of Chemistry, University of Chicago 929 E 57th St Chicago IL 60637 USA
| | - Josh W Kurutz
- Department of Chemistry, University of Chicago 929 E 57th St Chicago IL 60637 USA
| | - Alexander S Filatov
- Department of Chemistry, University of Chicago 929 E 57th St Chicago IL 60637 USA
| | - John S Anderson
- Department of Chemistry, University of Chicago 929 E 57th St Chicago IL 60637 USA
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7
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Theoretical perspective on mononuclear copper-oxygen mediated C–H and O–H activations: A comparison between biological and synthetic systems. CHINESE JOURNAL OF CATALYSIS 2022. [DOI: 10.1016/s1872-2067(21)63974-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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8
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Abstract
This tutorial review showcases recent (2015-2021) work describing ligand construction as it relates to the design of secondary coordination spheres (SCSs). Metalloenzymes, for example, utilize SCSs to stabilize reactive substrates, shuttle small molecules, and alter redox properties, promoting functional activity. In the realm of biomimetic chemistry, specific incorporation of SCS residues (e.g., Brønsted or Lewis acid/bases, crown ethers, redox groups etc.) has been shown to be equally critical to function. This contribution illustrates how fundamental advances in organic and inorganic chemistry have been used for the construction of such SCSs. These imaginative contributions have driven exciting findings in many transformations relevant to clean fuel generation, including small molecule (e.g., H+, N2, CO2, NOx, O2) reduction. In most cases, these reactions occur cooperatively, where both metal and ligand are requisite for substrate activation.
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Affiliation(s)
- Marcus W Drover
- Department of Chemistry and Biochemistry, The University of Windsor, 401 Sunset Avenue, Windsor, ON, N9B 3P4, Canada.
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9
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Bouchey CJ, Tolman WB. Involvement of a Formally Copper(III) Nitrite Complex in Proton-Coupled Electron Transfer and Nitration of Phenols. Inorg Chem 2022; 61:2662-2668. [PMID: 35078314 PMCID: PMC9835712 DOI: 10.1021/acs.inorgchem.1c03790] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
A unique high-valent copper nitrite species, LCuNO2, was accessed via the reversible one-electron oxidation of [M][LCuNO2] (M = NBu4+ or PPN+). The complex LCuNO2 reacts with 2,4,6-tri-tert-butylphenol via a typical proton-coupled electron transfer (PCET) to yield LCuTHF and the 2,4,6-tri-tert-butylphenoxyl radical. The reaction between LCuNO2 and 2,4-di-tert-butylphenol was more complicated. It yielded two products: the coupled bisphenol product expected from a H-atom abstraction and 2,4-di-tert-butyl-6-nitrophenol, the product of an unusual anaerobic nitration. Various mechanisms for the latter transformation were considered.
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Affiliation(s)
- Caitlin J Bouchey
- Department of Chemistry, Washington University in St. Louis, One Brookings Drive, Campus Box 1134, St. Louis, Missouri 63130, United States
- Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - William B Tolman
- Department of Chemistry, Washington University in St. Louis, One Brookings Drive, Campus Box 1134, St. Louis, Missouri 63130, United States
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10
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Léonard NG, Chantarojsiri T, Ziller JW, Yang JY. Cationic Effects on the Net Hydrogen Atom Bond Dissociation Free Energy of High-Valent Manganese Imido Complexes. J Am Chem Soc 2022; 144:1503-1508. [PMID: 35041788 PMCID: PMC9118977 DOI: 10.1021/jacs.1c09583] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Local electric fields can alter energy landscapes to impart enhanced reactivity in enzymes and at surfaces. Similar fields can be generated in molecular systems using charged functionalities. Manganese(V) salen nitrido complexes (salen = N,N'-ethylenebis(salicylideneaminato)) appended with a crown ether unit containing Na+ (1-Na), K+, (1-K), Ba2+ (1-Ba), Sr2+ (1-Sr), La3+ (1-La), or Eu3+ (1-Eu) cation were investigated to determine the effect of charge on pKa, E1/2, and the net bond dissociation free energy (BDFE) of N-H bonds. The series, which includes the manganese(V) salen nitrido without an appended crown, spans 4 units of charge. Bounds for the pKa values of the transient imido complexes were used with the Mn(VI/V) reduction potentials to calculate the N-H BDFEs of the imidos in acetonitrile. Despite a span of >700 mV and >9 pKa units across the series, the hydrogen atom BDFE only spans ∼6 kcal/mol (between 73 and 79 kcal/mol). These results suggest that the incorporation of cationic functionalities is an effective strategy for accessing wide ranges of reduction potentials and pKa values while minimally affecting the BDFE, which is essential to modulating electron, proton, or hydrogen atom transfer pathways.
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Affiliation(s)
- Nadia G Léonard
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Teera Chantarojsiri
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
| | - Joseph W Ziller
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Jenny Y Yang
- Department of Chemistry, University of California, Irvine, California 92697, United States
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
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11
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Skubi KL, Hooper RX, Mercado BQ, Bollmeyer MM, MacMillan SN, Lancaster KM, Holland PL. Iron Complexes of a Proton-Responsive SCS Pincer Ligand with a Sensitive Electronic Structure. Inorg Chem 2022; 61:1644-1658. [PMID: 34986307 PMCID: PMC8792349 DOI: 10.1021/acs.inorgchem.1c03499] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Sulfur/carbon/sulfur pincer ligands have an interesting combination of strong-field and weak-field donors, a coordination environment that is also present in the nitrogenase active site. Here, we explore the electronic structures of iron(II) and iron(III) complexes with such a pincer ligand, bearing a monodentate phosphine, thiolate S donor, amide N donor, ammonia, or CO. The ligand scaffold features a proton-responsive thioamide site, and the protonation state of the ligand greatly influences the reduction potential of iron in the phosphine complex. The N-H bond dissociation free energy, derived from the Bordwell equation, is 56 ± 2 kcal/mol. Electron paramagnetic resonance (EPR) spectroscopy and superconducting quantum interference device (SQUID) magnetometry measurements show that the iron(III) complexes with S and N as the fourth donors have an intermediate spin (S = 3/2) ground state with a large zero field splitting, and X-ray absorption spectra show a high Fe-S covalency. The Mössbauer spectrum changes drastically with the position of a nearby alkali metal cation in the iron(III) amido complex, and density functional theory calculations explain this phenomenon through a change between having the doubly occupied orbital as dz2 or dyz, as the former is more influenced by the nearby positive charge.
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Affiliation(s)
- Kazimer L. Skubi
- Department of Chemistry, Yale University, New Haven, Connecticut 06511
| | - Reagan X. Hooper
- Department of Chemistry, Yale University, New Haven, Connecticut 06511
| | | | - Melissa M. Bollmeyer
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853
| | - Samantha N. MacMillan
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853
| | - Kyle M. Lancaster
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853
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12
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Engbers S, Trifonova EA, Hess KM, Vries F, Klein JEMN. Synthesis of a Sterically Encumbered Pincer Au(III)−OH Complex. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100305] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Silène Engbers
- Molecular Inorganic Chemistry Stratingh Institute for Chemistry Faculty of Science and Engineering University of Groningen Nijenborgh 4 9747 AG Groningen The Netherlands
| | - Evgeniya A. Trifonova
- Molecular Inorganic Chemistry Stratingh Institute for Chemistry Faculty of Science and Engineering University of Groningen Nijenborgh 4 9747 AG Groningen The Netherlands
| | - Kristopher M. Hess
- Molecular Inorganic Chemistry Stratingh Institute for Chemistry Faculty of Science and Engineering University of Groningen Nijenborgh 4 9747 AG Groningen The Netherlands
| | - Folkert Vries
- Molecular Inorganic Chemistry Stratingh Institute for Chemistry Faculty of Science and Engineering University of Groningen Nijenborgh 4 9747 AG Groningen The Netherlands
| | - Johannes E. M. N. Klein
- Molecular Inorganic Chemistry Stratingh Institute for Chemistry Faculty of Science and Engineering University of Groningen Nijenborgh 4 9747 AG Groningen The Netherlands
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13
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Liu H, Shen Q. Well-defined organometallic Copper(III) complexes: Preparation, characterization and reactivity. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2021.213923] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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14
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Léonard NG, Dhaoui R, Chantarojsiri T, Yang JY. Electric Fields in Catalysis: From Enzymes to Molecular Catalysts. ACS Catal 2021; 11:10923-10932. [DOI: 10.1021/acscatal.1c02084] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Nadia G. Léonard
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Rakia Dhaoui
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Teera Chantarojsiri
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | - Jenny Y. Yang
- Department of Chemistry, University of California, Irvine, California 92697, United States
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15
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Loewen ND, Pattanayak S, Herber R, Fettinger JC, Berben LA. Quantification of the Electrostatic Effect on Redox Potential by Positive Charges in a Catalyst Microenvironment. J Phys Chem Lett 2021; 12:3066-3073. [PMID: 33750139 DOI: 10.1021/acs.jpclett.1c00406] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Charged functional groups in the secondary coordination sphere (SCS) of a heterogeneous nanoparticle or homogeneous electrocatalyst are of growing interest due to enhancements in reactivity that derive from specific interactions that stabilize substrate binding or charged intermediates. At the same time, accurate benchmarking of electrocatalyst systems most often depends on the development of linear free-energy scaling relationships. However, the thermodynamic axis in those kinetic-thermodynamic correlations is most often obtained by a direct electrochemical measurement of the catalyst redox potential and might be influenced by electrostatic effects of a charged SCS. In this report, we systematically probe positive charges in a SCS and their electrostatic contributions to the electrocatalyst redox potential. A series of 11 iron carbonyl clusters modified with charged and uncharged ligands was probed, and a linear correlation between the νCO absorption band energy and electrochemical redox potentials is observed except where the SCS is positively charged.
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Affiliation(s)
- Natalia D Loewen
- Department of Chemistry, University of California, 1 Shields Avenue, Davis, California 95616, United States
| | - Santanu Pattanayak
- Department of Chemistry, University of California, 1 Shields Avenue, Davis, California 95616, United States
| | - Rolfe Herber
- Racah Institute of Physics, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 91904, Israel
| | - James C Fettinger
- Department of Chemistry, University of California, 1 Shields Avenue, Davis, California 95616, United States
| | - Louise A Berben
- Department of Chemistry, University of California, 1 Shields Avenue, Davis, California 95616, United States
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16
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Weberg AB, McCollom SP, Thierer LM, Gau MR, Carroll PJ, Tomson NC. Using internal electrostatic fields to manipulate the valence manifolds of copper complexes. Chem Sci 2021; 12:4395-4404. [PMID: 34163703 PMCID: PMC8179517 DOI: 10.1039/d0sc06364a] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
A series of tetradentate tris(phosphinimine) ligands (R3P3tren) was developed and bound to CuI to form the trigonal pyramidal, C3v-symmetric cuprous complexes [R3P3tren-Cu][BArF4] (1PR3) (PR3 = PMe3, PMe2Ph, PMePh2, PPh3, PMe2(NEt2), BArF4 = B(C6F5)4). Electrochemical studies on the CuI complexes were undertaken, and the permethylated analog, 1PMe3, was found to display an unprecedentedly cathodic CuI/CuII redox potential (−780 mV vs. Fc/Fc+ in isobutyronitrile). Elucidation of the electronic structures of 1PR3via density functional theory (DFT) studies revealed atypical valence manifold configurations, resulting from strongly σ-donating phosphinimine moieties in the xy-plane that destabilize 2e (dxy/dx2−y2) orbital sets and uniquely stabilized a1 (dz2) orbitals. Support is provided that the a1 stabilizations result from intramolecular electrostatic fields (ESFs) generated from cationic character on the phosphinimine moieties in R3P3tren. This view is corroborated via 1-dimensional electrostatic potential maps along the z-axes of 1PR3 and their isostructural analogues. Experimental validation of this computational model is provided upon oxidation of 1PMe3 to the cupric complex [Me3P3tren-Cu][OTf]2 (2PMe3), which displays a characteristic Jahn–Teller distortion in the form of a see-saw, pseudo-Cs-symmetric geometry. A systematic anodic shift in the potential of the CuI/CuII redox couple as the steric bulk in the secondary coordination sphere increases is explained through the complexes' diminishing ability to access the ideal Cs-symmetric geometry upon oxidation. The observations and calculations discussed in this work support the presence of internal electrostatic fields within the copper complexes, which subsequently influence the complexes' properties via a method orthogonal to classic ligand field tuning. Secondary coordination sphere electrostatic effects tune the valence manifolds of copper centers, impacting molecular geometries, photophysical properties, and redox potentials.![]()
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Affiliation(s)
- Alexander B Weberg
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 South 34th Street Philadelphia Pennsylvania 19104 USA
| | - Samuel P McCollom
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 South 34th Street Philadelphia Pennsylvania 19104 USA
| | - Laura M Thierer
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 South 34th Street Philadelphia Pennsylvania 19104 USA
| | - Michael R Gau
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 South 34th Street Philadelphia Pennsylvania 19104 USA
| | - Patrick J Carroll
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 South 34th Street Philadelphia Pennsylvania 19104 USA
| | - Neil C Tomson
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 South 34th Street Philadelphia Pennsylvania 19104 USA
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17
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Martin DJ, Johnson SI, Mercado BQ, Raugei S, Mayer JM. Intramolecular Electrostatic Effects on O2, CO2, and Acetate Binding to a Cationic Iron Porphyrin. Inorg Chem 2020; 59:17402-17414. [DOI: 10.1021/acs.inorgchem.0c02703] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Daniel J. Martin
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Samantha I. Johnson
- Pacific Northwest National Laboratory (PNNL), Richland, Washington 99352, United States
| | - Brandon Q. Mercado
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Simone Raugei
- Pacific Northwest National Laboratory (PNNL), Richland, Washington 99352, United States
| | - James M. Mayer
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
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18
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VanNatta PE, Ramirez DA, Velarde AR, Ali G, Kieber-Emmons MT. Exceptionally High O–H Bond Dissociation Free Energy of a Dicopper(II) μ-Hydroxo Complex and Insights into the Geometric and Electronic Structure Origins Thereof. J Am Chem Soc 2020; 142:16292-16312. [DOI: 10.1021/jacs.0c06425] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Peter E. VanNatta
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112-0850, United States
| | - David A. Ramirez
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112-0850, United States
| | - Andres R. Velarde
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112-0850, United States
| | - Ghazanfar Ali
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112-0850, United States
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19
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Yang Y, Canty AJ, O'Hair RAJ. Gas-phase studies of copper(I)-mediated CO 2 extrusion followed by insertion of the heterocumulenes CS 2 or phenylisocyanate. JOURNAL OF MASS SPECTROMETRY : JMS 2020; 56:e4579. [PMID: 32578305 DOI: 10.1002/jms.4579] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 05/17/2020] [Accepted: 05/20/2020] [Indexed: 06/11/2023]
Abstract
The gas-phase extrusion-insertion reactions of the copper complex [bathophenanthroline (Bphen)CuI (O2 CC6 H5 )]2- , generated via electrospray ionization, was studied in a linear ion trap mass spectrometer with the combination of collision-induced dissociation (CID) and ion-molecule reaction (IMR) events. Multistage mass spectrometry (MSn ) experiments and density functional theory (DFT) demonstrated that extrusion of carbon dioxide from [(Bphen)Cu(O2 CC6 H5 )]2- (CID) gives the organometallic intermediate [(Bphen)Cu(C6 H5 )]2- , which subsequently reacts with carbon disulfide (IMR) via insertion to yield [(Bphen)Cu (SC(S)C6 H5 )]2- . The fragmentation of the product ion resulted in the formation of [Bphen]2- , [(Bphen)Cu]- and C6 H5 CS2 - under CID conditions. The formation of the latter two charge separation products thus provides evidence of C-C bond formation in the IMR step. Although analogous studies with isocyanate, which is isoelectronic with CS2 , showed a poor reactivity in the gas phase, the mechanistic understanding obtained from these model studies encourages future development of a solution phase protocol for the synthesis of amides from carboxylic acids and isocyanates mediated by copper(I) complexes.
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Affiliation(s)
- Yang Yang
- School of Chemistry, Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Parkville, Australia
| | - Allan J Canty
- School of Natural Sciences-Chemistry, University of Tasmania, Hobart, Australia
| | - Richard A J O'Hair
- School of Chemistry, Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Parkville, Australia
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20
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Mandal M, Elwell CE, Bouchey CJ, Zerk TJ, Tolman WB, Cramer CJ. Mechanisms for Hydrogen-Atom Abstraction by Mononuclear Copper(III) Cores: Hydrogen-Atom Transfer or Concerted Proton-Coupled Electron Transfer? J Am Chem Soc 2019; 141:17236-17244. [PMID: 31617707 DOI: 10.1021/jacs.9b08109] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
In a possibly biomimetic fashion, formally copper(III)-oxygen complexes LCu(III)-OH (1) and LCu(III)-OOCm (2) (L2- = N,N'-bis(2,6-diisopropylphenyl)-2,6-pyridinedicarboxamide, Cm = α,α-dimethylbenzyl) have been shown to activate X-H bonds (X = C, O). Herein, we demonstrate similar X-H bond activation by a formally Cu(III) complex supported by the same dicarboxamido ligand, LCu(III)-O2CAr1 (3, Ar1 = meta-chlorophenyl), and we compare its reactivity to that of 1 and 2. Kinetic measurements revealed a second order reaction with distinct differences in the rates: 1 reacts the fastest in the presence of O-H or C-H based substrates, followed by 3, which is followed by (unreactive) 2. The difference in reactivity is attributed to both a varying oxidizing ability of the studied complexes and to a variation in X-H bond functionalization mechanisms, which in these cases are characterized as either a hydrogen-atom transfer (HAT) or a concerted proton-coupled electron transfer (cPCET). Select theoretical tools have been employed to distinguish these two cases, both of which generally focus on whether the electron (e-) and proton (H+) travel "together" as a true H atom, (HAT), or whether the H+ and e- are transferred in concert, but travel between different donor/acceptor centers (cPCET). In this work, we reveal that both mechanisms are active for X-H bond activation by 1-3, with interesting variations as a function of substrate and copper functionality.
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Affiliation(s)
- Mukunda Mandal
- Department of Chemistry, Minnesota Supercomputing Institute, Chemical Theory Center, and Center for Metals in Biocatalysis , University of Minnesota , 207 Pleasant Street SE , Minneapolis , Minnesota 55455 , United States
| | - Courtney E Elwell
- Department of Chemistry, Minnesota Supercomputing Institute, Chemical Theory Center, and Center for Metals in Biocatalysis , University of Minnesota , 207 Pleasant Street SE , Minneapolis , Minnesota 55455 , United States
| | - Caitlin J Bouchey
- Department of Chemistry, Minnesota Supercomputing Institute, Chemical Theory Center, and Center for Metals in Biocatalysis , University of Minnesota , 207 Pleasant Street SE , Minneapolis , Minnesota 55455 , United States.,Department of Chemistry , Washington University in St. Louis , One Brookings Drive, Campus Box 1134 , St. Louis , Missouri 63130 , United States
| | - Timothy J Zerk
- Department of Chemistry , Washington University in St. Louis , One Brookings Drive, Campus Box 1134 , St. Louis , Missouri 63130 , United States
| | - William B Tolman
- Department of Chemistry , Washington University in St. Louis , One Brookings Drive, Campus Box 1134 , St. Louis , Missouri 63130 , United States
| | - Christopher J Cramer
- Department of Chemistry, Minnesota Supercomputing Institute, Chemical Theory Center, and Center for Metals in Biocatalysis , University of Minnesota , 207 Pleasant Street SE , Minneapolis , Minnesota 55455 , United States
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21
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Zerk TJ, Saouma CT, Mayer JM, Tolman WB. Low Reorganization Energy for Electron Self-Exchange by a Formally Copper(III,II) Redox Couple. Inorg Chem 2019; 58:14151-14158. [PMID: 31577145 DOI: 10.1021/acs.inorgchem.9b02185] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The rate constant for electron self-exchange (k11) between LCuOH and [LCuOH]- (L = bis-2,6-(2,6-diisopropylphenyl)carboximidopyridine) was determined using the Marcus cross relation. This work involved measurement of the rate of the cross-reaction between [Bu4N][LCuOH] and [Fc][BAr4F] (Fc+ = ferrocenium; BAr4F = tetrakis[3,5-bis(trifluoromethyl)phenyl]borate)) by stopped-flow methods at -88 °C in CH2Cl2 and measurement of the equilibrium constant for the redox process by UV-vis titrations under the same conditions. A value of k11 = 3 × 104 M-1 s-1 (-88 °C) led to estimation of a value 9 × 106 M-1 s-1 at 25 °C, which is among the highest values known for copper redox couples. Further Marcus analysis enabled determination of a low reorganization energy, λ = 0.95 ± 0.17 eV, attributed to minimal structural variation between the redox partners. In addition, the reaction entropy (ΔS°) associated with the LCuOH/[LCuOH]- self-exchange was determined from the temperature dependence of the redox potentials, and found to be dependent upon ionic strength. Comparisons to other Cu redox systems and potential new applications for the formally CuIII,II system are discussed.
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Affiliation(s)
- Timothy J Zerk
- Department of Chemistry , Washington University in St. Louis , One Brookings Hall, Campus Box 1134 , St. Louis , Missouri 63130-4899 , United States
| | - Caroline T Saouma
- Department of Chemistry , University of Utah , 315 S 1400 E , Salt Lake City , Utah 84112 , United States
| | - James M Mayer
- Department of Chemistry , Yale University , 225 Prospect Street , New Haven , Connecticut 06520-8107 , United States
| | - William B Tolman
- Department of Chemistry , Washington University in St. Louis , One Brookings Hall, Campus Box 1134 , St. Louis , Missouri 63130-4899 , United States
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22
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A Comparative Study of the Catalytic Behaviour of Alkoxy-1,3,5-Triazapentadiene Copper(II) Complexes in Cyclohexane Oxidation. INORGANICS 2019. [DOI: 10.3390/inorganics7070082] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The mononuclear copper complexes [Cu{NH=C(OR)NC(OR)=NH}2] with alkoxy-1,3,5-triazapentadiene ligands that have different substituents (R = Me (1), Et (2), nPr (3), iPr (4), CH2CH2OCH3 (5)) were prepared, characterized (including the single crystal X-ray analysis of 3) and studied as catalysts in the mild oxidation of alkanes with H2O2 as an oxidant, pyridine as a promoting agent and cyclohexane as a main model substrate. The complex 4 showed the highest activity with a yield of products up to 18.5% and turnover frequency (TOF) up to 41 h−1. Cyclohexyl hydroperoxide was the main reaction product in all cases. Selectivity parameters in the oxidation of substituted cyclohexanes and adamantane disclosed a dominant free radical reaction mechanism with hydroxyl radicals as C–H-attacking species. The main overoxidation product was 6-hydroxyhexanoic acid, suggesting the presence of a secondary reaction mechanism of a different type. All complexes undergo gradual alteration of their structures in acetonitrile solutions to produce catalytically-active intermediates, as evidenced by UV/Vis spectroscopy and kinetic studies. Complex 4, having tertiary C–H bonds in its iPr substituents, showed the fastest alteration rate, which can be significantly suppressed by using the CD3CN solvent instead of CH3CN one. The observed process was associated to an autocatalytic oxidation of the alkoxy-1,3,5-triazapentadiene ligand. The deuterated complex 4-d32 was prepared and showed higher stability under the same conditions. The complexes 1 and 4 showed different reactivity in the formation of H218O from 18O2 in acetonitrile solutions.
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23
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Shi K, Mathivathanan L, Boudalis AK, Turek P, Chakraborty I, Raptis RG. Nitrite Reduction by Trinuclear Copper Pyrazolate Complexes: An Example of a Catalytic, Synthetic Polynuclear NO Releasing System. Inorg Chem 2019; 58:7537-7544. [DOI: 10.1021/acs.inorgchem.9b00748] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kaige Shi
- Department of Chemistry and Biochemistry and Biomolecular Sciences Institute, Florida International University, 11200 SW Eighth Street, Miami, Florida 33199, United States
| | - Logesh Mathivathanan
- Department of Chemistry and Biochemistry and Biomolecular Sciences Institute, Florida International University, 11200 SW Eighth Street, Miami, Florida 33199, United States
| | - Athanassios K. Boudalis
- Institut de Chimie UMR 7177/Université de Strasbourg 4, rue Blaise Pascal/CS 90032, F-67081 Strasbourg CEDEX, France
| | - Philippe Turek
- Institut de Chimie UMR 7177/Université de Strasbourg 4, rue Blaise Pascal/CS 90032, F-67081 Strasbourg CEDEX, France
| | - Indranil Chakraborty
- Department of Chemistry and Biochemistry and Biomolecular Sciences Institute, Florida International University, 11200 SW Eighth Street, Miami, Florida 33199, United States
| | - Raphael G. Raptis
- Department of Chemistry and Biochemistry and Biomolecular Sciences Institute, Florida International University, 11200 SW Eighth Street, Miami, Florida 33199, United States
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24
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Elwell CE, Neisen BD, Tolman WB. Copper Complexes of Multidentate Carboxamide Ligands. Inorganica Chim Acta 2019; 485:131-139. [PMID: 31105329 DOI: 10.1016/j.ica.2018.10.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The copper coordination chemistry of two multidentate carboxamido ligands derived from HL1 (offering two quinolyl and one carboxamide donor) and H4L2 (with two pyridine(dicarboxamido) units linked by naphthalene spacers) was explored. The former was chosen because upon deprotonation it would provide a monoanionic mer-coordinating N-donor set that would model the putative deprotonated form of the His-brace in copper monooxygenases, while the latter was designed to bind two copper ions and enable comparisons to other systems with different ligand spacers. Upon reaction with Cu(I)-mesityl, HL1 yielded a symmetric dimer (L1Cu)2 in which each bis(quinolyl)amide ligand binds via two N-donors to one Cu(I) ion and via the third to the other Cu(I) center. Monomeric Cu(II) complexes [L 1 Cu(H 2 O) 2 ](OTf) and L 1 2 Cu were also characterized. Treatment of H4L2 with Cu(OTf)2 and excess Me4NOH (in CH3CN, pyridine/H2O, or MeOH) yielded complexes with anions of general formula [L 2 Cu 2 (X)]n-, where X = CH3CONH- (n = 1), CO3 2- (n = 2), or MeO- (n = 1). X-ray structures of these complexes revealed the (L2)4- ligand binding to two Cu(II) ions in an open paddle-wheel geometry, with an additional bridging ligand (X) completing the square planar coordination sphere of each metal ion. The open paddlewheel motif differs from the more 'open' puckered geometry seen with related ligands with different spacer units.
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Affiliation(s)
- Courtney E Elwell
- Department of Chemistry, University of Minnesota, 207 Pleasant St. SE, Minneapolis, MN 55455
| | - Benjamin D Neisen
- Department of Chemistry, University of Minnesota, 207 Pleasant St. SE, Minneapolis, MN 55455
| | - William B Tolman
- Department of Chemistry, Washington University in St. Louis, Campus Box 1134, 1 Brookings Drive, St. Louis, MO 63130
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25
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Maity S, Ghosh S, Ghosh A. Elucidating the secondary effect in the Lewis acid mediated anodic shift of electrochemical oxidation of a Cu(ii) complex with a N2O2 donor unsymmetrical ligand. Dalton Trans 2019; 48:14898-14913. [DOI: 10.1039/c9dt03323h] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The causes behind the fluctuations from a linear dependence of the electrochemical signal of a guest bound metalloligand [CuL] with the Lewis acidity of redox-inactive cations were established by using UV-vis spectroscopy and cyclic voltammetry.
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Affiliation(s)
- Souvik Maity
- Department of Chemistry
- University College of Science
- University of Calcutta
- Kolkata 700009
- India
| | - Soumavo Ghosh
- Department of Chemistry
- University College of Science
- University of Calcutta
- Kolkata 700009
- India
| | - Ashutosh Ghosh
- Department of Chemistry
- University College of Science
- University of Calcutta
- Kolkata 700009
- India
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26
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Isaac JA, Thibon-Pourret A, Durand A, Philouze C, Le Poul N, Belle C. High-valence CuIICuIII species in action: demonstration of aliphatic C–H bond activation at room temperature. Chem Commun (Camb) 2019; 55:12711-12714. [DOI: 10.1039/c9cc04422a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The electrochemically generated CuIICuIII mixed-valence species promotes activation of strong aliphatic C–H bonds (i.e. toluene), turning from stoichiometric to catalytic upon addition of a base.
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Affiliation(s)
| | | | - Amélie Durand
- Université Grenoble Alpes
- CNRS
- ICMG
- 38000 Grenoble
- France
| | | | - Nicolas Le Poul
- Université de Bretagne Occidentale
- CNRS UMR 6521
- 29238 Brest
- France
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27
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Dereli B, Momeni MR, Cramer CJ. Density Functional Modeling of Ligand Effects on Electronic Structure and C–H Bond Activation Activity of Copper(III) Hydroxide Compounds. Inorg Chem 2018; 57:9807-9813. [DOI: 10.1021/acs.inorgchem.8b01530] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Büsra Dereli
- Department of Chemistry, Minnesota Supercomputing Institute, and Chemical Theory Center, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Mohammad R. Momeni
- Department of Chemistry, Minnesota Supercomputing Institute, and Chemical Theory Center, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Christopher J. Cramer
- Department of Chemistry, Minnesota Supercomputing Institute, and Chemical Theory Center, University of Minnesota, Minneapolis, Minnesota 55455, United States
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