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Hunter NH, Thomas CM. Polarized metal-metal multiple bonding and reactivity of phosphinoamide-bridged heterobimetallic group IV/cobalt compounds. Dalton Trans 2024; 53:15764-15781. [PMID: 39224084 DOI: 10.1039/d4dt02064b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
Heterobimetallic complexes are studied for their ability to mimic biological systems as well as active sites in heterogeneous catalysts. While specific interest in early/late heterobimetallic systems has fluctuated, they serve as important models to fundamentally understand metal-metal bonding. Specifically, the polarized metal-metal multiple bonds formed in highly reduced early/late heterobimetallic complexes exemplify how each metal modulates the electronic environment and reactivity of the complex as a whole. In this Perspective, we chronicle the development of phosphinoamide-supported group IV/cobalt heterobimetallic complexes. This combination of metals allows access to a low valent Co-I center, which performs a rich variety of bond activation reactions when coupled with the pendent Lewis acidic metal center. Conversely, the low valent late transition metal is also observed to act as an electron reservoir, allowing for redox processes to occur at the d0 group IV metal site. Most of the bond activation reactions carried out by phosphinoamide-bridged M/Co-I (M = Ti, Zr, Hf) complexes are facilitated by cleavage of metal-metal multiple bonds, which serve as readily accessible electron reservoirs. Comparative studies in which both the number of buttressing ligands as well as the identity of the early metal were varied to give a library of heterobimetallic complexes are summarized, providing a thorough understanding of the reactivity of M/Co-I heterobimetallic systems.
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Affiliation(s)
- Nathanael H Hunter
- Department of Chemistry and Biochemistry, The Ohio State University, 100 W, 18th Ave, Columbus, OH 43210, USA.
| | - Christine M Thomas
- Department of Chemistry and Biochemistry, The Ohio State University, 100 W, 18th Ave, Columbus, OH 43210, USA.
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2
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Saha S, Krause JA, Guan H. C(sp)-H, S-H, and Sn-H Bond Activation with a Cobalt(I) Pincer Complex. Inorg Chem 2024; 63:13689-13699. [PMID: 38976491 DOI: 10.1021/acs.inorgchem.4c01993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
This study focuses on the stoichiometric reactions of {2,6-(iPr2PO)2C6H3}Co(PMe3)2 with terminal alkynes, thiols, and tin hydrides as part of an effort to develop catalytic, two-electron processes with cobalt. This specific Co(I) pincer complex proves to be effective for cleaving the C(sp)-H, S-H, and Sn-H bonds to give oxidative addition products with the general formula {2,6-(iPr2PO)2C6H3}CoHX(PMe3) (X = alkynyl, thiolate, and stannyl groups) along with the free PMe3. These reactions typically reach completion when the substituents on acetylene, sulfur, and tin are electron-withdrawing groups (e.g., phenyl, pyridyl, and alkenyl groups). In contrast, alkyl-substituted acetylenes, 1-pentanethiol, and tributyltin hydride are partially converted due to the equilibria with the corresponding oxidative addition products. The Co(I) pincer complex is not a hydrothiolation catalyst but capable of catalyzing the hydrostannation of terminal alkynes with Ph3SnH to produce β-(Z)-alkenylstannanes selectively.
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Affiliation(s)
- Sayantani Saha
- Department of Chemistry, University of Cincinnati, P.O. Box 210172, Cincinnati, Ohio 45221-0172, United States
| | - Jeanette A Krause
- Department of Chemistry, University of Cincinnati, P.O. Box 210172, Cincinnati, Ohio 45221-0172, United States
| | - Hairong Guan
- Department of Chemistry, University of Cincinnati, P.O. Box 210172, Cincinnati, Ohio 45221-0172, United States
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3
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Sun Y, Zhang J, Zeng Y, Meng L, Li X. Mechanism and Stereoselectivity Control of Terminal Alkyne Dimerization Activated by a Zr/Co Heterobimetallic Complex: A DFT Study. J Org Chem 2024; 89:605-616. [PMID: 38096545 DOI: 10.1021/acs.joc.3c02359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2024]
Abstract
Heterobimetallic complexes have recently garnered considerable attention in organic synthesis owing to their high activity and selectivity, which surpass those of monometallic complexes. In this study, the detailed mechanisms of terminal alkyne dimerization activated by the heterobimetallic Zr/Co complex, as well as the different stereoselectivities of Me3SiC≡CH and PhC≡CH dimerization, were investigated and elucidated by using density functional theory calculations. After excluding the three-molecule reaction and outer-sphere mechanisms, the inner-sphere mechanism was determined as the most optimal process. The inner-sphere mechanism involves four processes: THF dissociation and coordination of the first alkyne; ligand migration and C-H activation; N2 dissociation and insertion of the second alkyne; and reductive elimination. The stereoselectivity between the E-/Z- and gem-isomers is determined by the C-C coupling mode of the two alkynes and that of the E- and Z-isomers is determined by the sequence of the C-C coupling and hydrogen migration in the reductive elimination process. Me3SiC≡CH dimerization yields only an E-isomer owing to the large differences in the distortion and interaction energies, whereas PhC≡CH dimerization produces an E-, Z-, and gem-isomers owing to the reduced interaction energy differences.
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Affiliation(s)
- Yuanyuan Sun
- College of Chemistry and Material Science, Hebei Key Laboratory of Inorganic and Nano-Materials, National Demonstratin Center for Experimental Chemistry, Hebei Normal University, Shijiazhuang 050024, P. R. China
| | - Jinying Zhang
- College of Chemistry and Material Science, Hebei Key Laboratory of Inorganic and Nano-Materials, National Demonstratin Center for Experimental Chemistry, Hebei Normal University, Shijiazhuang 050024, P. R. China
| | - Yanli Zeng
- College of Chemistry and Material Science, Hebei Key Laboratory of Inorganic and Nano-Materials, National Demonstratin Center for Experimental Chemistry, Hebei Normal University, Shijiazhuang 050024, P. R. China
| | - Lingpeng Meng
- College of Chemistry and Material Science, Hebei Key Laboratory of Inorganic and Nano-Materials, National Demonstratin Center for Experimental Chemistry, Hebei Normal University, Shijiazhuang 050024, P. R. China
| | - Xiaoyan Li
- College of Chemistry and Material Science, Hebei Key Laboratory of Inorganic and Nano-Materials, National Demonstratin Center for Experimental Chemistry, Hebei Normal University, Shijiazhuang 050024, P. R. China
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4
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Govindarajan R, Deolka S, Khusnutdinova JR. Heterometallic bond activation enabled by unsymmetrical ligand scaffolds: bridging the opposites. Chem Sci 2022; 13:14008-14031. [PMID: 36540828 PMCID: PMC9728565 DOI: 10.1039/d2sc04263k] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 10/27/2022] [Indexed: 08/19/2023] Open
Abstract
Heterobi- and multimetallic complexes providing close proximity between several metal centers serve as active species in artificial and enzymatic catalysis, and in model systems, showing unique modes of metal-metal cooperative bond activation. Through the rational design of well-defined, unsymmetrical ligand scaffolds, we create a convenient approach to support the assembly of heterometallic species in a well-defined and site-specific manner, preventing them from scrambling and dissociation. In this perspective, we will outline general strategies for the design of unsymmetrical ligands to support heterobi- and multimetallic complexes that show reactivity in various types of heterometallic cooperative bond activation.
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Affiliation(s)
- R Govindarajan
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha, Onna-son 904-0495 Okinawa Japan
| | - Shubham Deolka
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha, Onna-son 904-0495 Okinawa Japan
| | - Julia R Khusnutdinova
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha, Onna-son 904-0495 Okinawa Japan
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5
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Hunter NH, Lane EM, Gramigna KM, Moore CE, Thomas CM. C–H Bond Activation Facilitated by Bis(phosphinoamide) Heterobimetallic Zr/Co Complexes. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nathanael H. Hunter
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Elizabeth M. Lane
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Kathryn M. Gramigna
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States
| | - Curtis E. Moore
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Christine M. Thomas
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
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6
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Weber S, Veiros LF, Kirchner K. Selective Manganese-Catalyzed Dimerization and Cross-Coupling of Terminal Alkynes. ACS Catal 2021; 11:6474-6483. [PMID: 34123484 PMCID: PMC8185884 DOI: 10.1021/acscatal.1c01137] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 05/05/2021] [Indexed: 11/28/2022]
Abstract
![]()
Herein, efficient
manganese-catalyzed dimerization of terminal
alkynes to afford 1,3-enynes is described. This reaction is atom economic,
implementing an inexpensive, earth-abundant nonprecious metal catalyst.
The precatalyst is the bench-stable alkyl bisphosphine Mn(I) complex fac-[Mn(dippe)(CO)3(CH2CH2CH3)]. The catalytic process is initiated by migratory
insertion of a CO ligand into the Mn–alkyl bond to yield an
acyl intermediate that undergoes rapid C–H bond cleavage of
alkyne, forming an active Mn(I) acetylide catalyst [Mn(dippe)(CO)2(C≡CPh)(η2-HC≡CPh)] together
with liberated butanal. A range of aromatic and aliphatic terminal
alkynes were efficiently and selectively converted into head-to-head Z-1,3-enynes and head-to-tail gem-1,3-enynes,
respectively, in good to excellent yields. Moreover, cross-coupling
of aromatic and aliphatic alkynes selectively yields head-to-tail gem-1,3-enynes. In all cases, the reactions were performed
at 70 °C with a catalyst loading of 1–2 mol %. A mechanism
based on density functional theory (DFT) calculations is presented.
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Affiliation(s)
- Stefan Weber
- Institute of Applied Synthetic Chemistry, Vienna University of Technology, Getreidemarkt 9, A-1060 Vienna, Austria
| | - Luis F. Veiros
- Centro de Química Estrutural and Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, Av Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Karl Kirchner
- Institute of Applied Synthetic Chemistry, Vienna University of Technology, Getreidemarkt 9, A-1060 Vienna, Austria
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Charles RM, Brewster TP. H 2 and carbon-heteroatom bond activation mediated by polarized heterobimetallic complexes. Coord Chem Rev 2021; 433:213765. [PMID: 35418712 PMCID: PMC9004596 DOI: 10.1016/j.ccr.2020.213765] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The field of heterobimetallic chemistry has rapidly expanded over the last decade. In addition to their interesting structural features, heterobimetallic structures have been found to facilitate a range of stoichiometric bond activations and catalytic processes. The accompanying review summarizes advances in this area since January of 2010. The review encompasses well-characterized heterobimetallic complexes, with a particular focus on mechanistic details surrounding their reactivity applications.
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Affiliation(s)
- R Malcolm Charles
- Department of Chemistry, The University of Memphis, 3744 Walker Ave., Smith Chemistry Building, Memphis, TN 38152, United States
| | - Timothy P Brewster
- Department of Chemistry, The University of Memphis, 3744 Walker Ave., Smith Chemistry Building, Memphis, TN 38152, United States
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8
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Weber SM, Hilt G. Late 3d Metal-Catalyzed (Cross-) Dimerization of Terminal and Internal Alkynes. Front Chem 2021; 9:635826. [PMID: 33777899 PMCID: PMC7991731 DOI: 10.3389/fchem.2021.635826] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 01/22/2021] [Indexed: 11/23/2022] Open
Abstract
This review will outline the recent advances in chemo-, regio-, and stereoselective (cross-) dimerization of terminal alkynes to generate 1,3-enynes using different types of iron and cobalt catalysts with altering oxidation states of the active species. In general, the used ligands have a crucial effect on the stereoselectivity of the reaction; e.g., bidentate phosphine ligands in cobalt catalysts can generate the E-configured head-to-head dimerization product, while tridentate phosphine ligands can generate either the Z-configured head-to-head dimerization product or the branched head-to-tail isomer. Furthermore, the hydroalkynylation of silyl-substituted acetylenes as donors to internal alkynes as acceptors will be discussed using cobalt and nickel catalysts.
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Affiliation(s)
- Sebastian M Weber
- Fachbereich Chemie, Philipps-Universität Marburg, Marburg, Germany.,Institut für Chemie, Carl Von Ossietzky Universität Oldenburg, Oldenburg, Germany
| | - Gerhard Hilt
- Institut für Chemie, Carl Von Ossietzky Universität Oldenburg, Oldenburg, Germany
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9
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Dasgupta A, Stefkova K, Babaahmadi R, Yates BF, Buurma NJ, Ariafard A, Richards E, Melen RL. Site-Selective C sp3-C sp/C sp3-C sp2 Cross-Coupling Reactions Using Frustrated Lewis Pairs. J Am Chem Soc 2021; 143:4451-4464. [PMID: 33719443 PMCID: PMC8041292 DOI: 10.1021/jacs.1c01622] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Indexed: 02/08/2023]
Abstract
The donor-acceptor ability of frustrated Lewis pairs (FLPs) has led to widespread applications in organic synthesis. Single electron transfer from a donor Lewis base to an acceptor Lewis acid can generate a frustrated radical pair (FRP) depending on the substrate and energy required (thermal or photochemical) to promote an FLP into an FRP system. Herein, we report the Csp3-Csp cross-coupling reaction of aryl esters with terminal alkynes using the B(C6F5)3/Mes3P FLP. Significantly, when the 1-ethynyl-4-vinylbenzene substrate was employed, the exclusive formation of Csp3-Csp cross-coupled products was observed. However, when 1-ethynyl-2-vinylbenzene was employed, solvent-dependent site-selective Csp3-Csp or Csp3-Csp2 cross-coupling resulted. The nature of these reaction pathways and their selectivity has been investigated by extensive electron paramagnetic resonance (EPR) studies, kinetic studies, and density functional theory (DFT) calculations both to elucidate the mechanism of these coupling reactions and to explain the solvent-dependent site selectivity.
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Affiliation(s)
- Ayan Dasgupta
- Cardiff
Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, Cymru/Wales, United Kingdom
| | - Katarina Stefkova
- Cardiff
Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, Cymru/Wales, United Kingdom
| | - Rasool Babaahmadi
- School
of Natural Sciences-Chemistry, University
of Tasmania Private Bag 75, Hobart, Tasmania 7001, Australia
| | - Brian F. Yates
- School
of Natural Sciences-Chemistry, University
of Tasmania Private Bag 75, Hobart, Tasmania 7001, Australia
| | - Niklaas J. Buurma
- Cardiff
Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, Cymru/Wales, United Kingdom
| | - Alireza Ariafard
- School
of Natural Sciences-Chemistry, University
of Tasmania Private Bag 75, Hobart, Tasmania 7001, Australia
| | - Emma Richards
- Cardiff
Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, Cymru/Wales, United Kingdom
| | - Rebecca L. Melen
- Cardiff
Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, Cymru/Wales, United Kingdom
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10
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Wang Q, Brooks SH, Liu T, Tomson NC. Tuning metal-metal interactions for cooperative small molecule activation. Chem Commun (Camb) 2021; 57:2839-2853. [PMID: 33624638 PMCID: PMC8274379 DOI: 10.1039/d0cc07721f] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cluster complexes have attracted interest for decades due to their promise of drawing analogies to metallic surfaces and metalloenzyme active sites, but only recently have chemists started to develop ligand scaffolds that are specifically designed to support multinuclear transition metal cores. Such ligands not only hold multiple metal centers in close proximity but also allow for fine-tuning of their electronic structures and surrounding steric environments. This Feature Article highlights ligand designs that allow for cooperative small molecule activation at cluster complexes, with a particular focus on complexes that contain metal-metal bonds. Two useful ligand-design elements have emerged from this work: a degree of geometric flexibility, which allows for novel small molecule activation modes, and the use of redox-active ligands to provide electronic flexibility to the cluster core. The authors have incorporated these factors into a unique class of dinucleating macrocycles (nPDI2). Redox-active fragments in nPDI2 mimic the weak-overlap covalent bonding that is characteristic of M-M interactions, and aliphatic linkers in the ligand backbone provide geometric flexibility, allowing for interconversion between a range of geometries as the dinuclear core responds to the requirements of various small molecule substrates. The union of these design elements appears to be a powerful combination for analogizing critical aspects of heterogeneous and metalloenzyme catalysts.
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Affiliation(s)
- Qiuran Wang
- P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, USA.
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11
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Del Rosal I, Lassalle S, Dinoi C, Thieuleux C, Maron L, Camp C. Mechanistic investigations via DFT support the cooperative heterobimetallic C-H and O-H bond activation across Ta[double bond, length as m-dash]Ir multiple bonds. Dalton Trans 2021; 50:504-510. [PMID: 33210676 DOI: 10.1039/d0dt03818k] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A rare heterobimetallic oxidative addition of X-H (X = C, O) bonds is reported. DFT suggests that steric constraints around the bimetallic core play a critical role to synergistically activate C-H bonds across the two metals and thus explains the exceptional H/D exchange catalytic activity of unhindered surface organometallic Ta/Ir species observed experimentally.
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Affiliation(s)
- Iker Del Rosal
- Université de Toulouse et CNRS, INSA, UPS, UMR 5215, LPCNO, 135 Avenue de Rangueil, F-31077 Toulouse, France
| | - Sébastien Lassalle
- Laboratory of Chemistry, Catalysis, Polymers and Processes, C2P2 UMR 5265, Université de Lyon, Institut de Chimie de Lyon, CNRS, Université Lyon 1, CPE Lyon, 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France.
| | - Chiara Dinoi
- Université de Toulouse et CNRS, INSA, UPS, UMR 5215, LPCNO, 135 Avenue de Rangueil, F-31077 Toulouse, France
| | - Chloé Thieuleux
- Laboratory of Chemistry, Catalysis, Polymers and Processes, C2P2 UMR 5265, Université de Lyon, Institut de Chimie de Lyon, CNRS, Université Lyon 1, CPE Lyon, 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France.
| | - Laurent Maron
- Université de Toulouse et CNRS, INSA, UPS, UMR 5215, LPCNO, 135 Avenue de Rangueil, F-31077 Toulouse, France
| | - Clément Camp
- Laboratory of Chemistry, Catalysis, Polymers and Processes, C2P2 UMR 5265, Université de Lyon, Institut de Chimie de Lyon, CNRS, Université Lyon 1, CPE Lyon, 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France.
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12
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Zhang H, Hatzis GP, Dickie DA, Moore CE, Thomas CM. Redox chemistry and H-atom abstraction reactivity of a terminal zirconium(iv) oxo compound mediated by an appended cobalt(i) center. Chem Sci 2020; 11:10729-10736. [PMID: 34094325 PMCID: PMC8162367 DOI: 10.1039/d0sc04229c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The reactivity of the terminal zirconium(iv) oxo complex, O
Created by potrace 1.16, written by Peter Selinger 2001-2019
]]>
Zr(MesNPiPr2)3CoCNtBu (2), is explored, revealing unique redox activity imparted by the pendent redox active cobalt(i) center. Oxo complex 2 can be chemically reduced using Na/Hg or Ph3C• to afford the ZrIV/Co0 complexes [(μ-Na)OZr(MesNPiPr2)3CoCNtBu]2 (3) and Ph3COZr(MesNPiPr2)3CoCNtBu (4), respectively. Based on the cyclic voltammogram of 2, Ph3˙ should not be sufficiently reducing to achieve the chemical reduction of 2, but sufficient driving force for the reaction is provided by the nucleophilicity of the terminal oxo fragment and its affinity to bind Ph3C+. Accordingly, 2 reacts readily with [Ph3C][BPh4] and Ph3CCl to afford [Ph3COZr(MesNPiPr2)3CoCNtBu][BPh4] ([5][BPh4]) and Ph3COZr(MesNPiPr2)3CoCl (6), respectively. The chemical oxidation of 2 is also investigated, revealing that oxidation of 2 is accompanied by immediate hydrogen atom abstraction to afford the hydroxide complex [HOZr(MesNPiPr2)3CoCNtBu]+ ([9]+). Thus it is posited that the transient [OZr(MesNPiPr2)3CoCNtBu]+ [2]+ cation generated upon oxidation combines the basicity of a nucleophilic early metal oxo fragment with the oxidizing power of the appended cobalt center to facilitate H-atom abstraction. Bimetallic cooperativity is demonstrated with a Co/Zr complex featuring both nucleophilic Zr(iv) oxo and redox active Co sites.![]()
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Affiliation(s)
- Hongtu Zhang
- Department of Chemistry and Biochemistry, The Ohio State University 100 W. 18th Ave Columbus OH 43210 USA
| | - Gregory P Hatzis
- Department of Chemistry and Biochemistry, The Ohio State University 100 W. 18th Ave Columbus OH 43210 USA
| | - Diane A Dickie
- Department of Chemistry, University of Virginia 409 McCormick Road, PO Box 400319 Charlottesville VA 22904 USA
| | - Curtis E Moore
- Department of Chemistry and Biochemistry, The Ohio State University 100 W. 18th Ave Columbus OH 43210 USA
| | - Christine M Thomas
- Department of Chemistry and Biochemistry, The Ohio State University 100 W. 18th Ave Columbus OH 43210 USA
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13
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Affiliation(s)
- Qiuming Liang
- Davenport Chemical Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
| | - Kasumi Hayashi
- Davenport Chemical Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
| | - Datong Song
- Davenport Chemical Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
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