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Das S, Buschermöhle J, Zant DW, Schmidtmann M, van der Vlugt JI. Selective Manipulation of Well-Defined Trinuclear Pd(II)-Complexes. Chemistry 2024; 30:e202400044. [PMID: 38334955 DOI: 10.1002/chem.202400044] [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: 01/12/2024] [Revised: 02/09/2024] [Accepted: 02/09/2024] [Indexed: 02/10/2024]
Abstract
Several strategies are available to design well-defined multimetallic molecular entities bearing functional ligands. Substoichiometric exchange reactions in the coordination sphere of pre-existing multinuclear precursors are relatively underexploited in this context. Palladium(II) acetate is not a mononuclear compound in the solid state but rather exists as a trimer, i. e. [Pd3(OAc)6]. Although this material is ubiquitously used to synthesize mononuclear Pd species, it may principally also lend itself to selective exchange of some of the edge-sharing acetate units in its triangular motif, whilst keeping the overall multinuclear architecture intact. Strikingly, little is known about the controlled manipulation and substoichiometric substitution chemistry of this well-defined conglomerate. We herein conclusively demonstrate that, for the first time, the targeted exchange of two or four acetate units from the Pd3(acetate)6 platform is possible, thereby installing either one or two new tridentate ligands onto this trinuclear architecture. Follow-up exchange and substitution chemistry is available without disrupting the multimetallic nature of the core structure. New complexes 2-7 are all conclusively characterized using multinuclear NMR spectroscopy, UV-vis and IR spectroscopy as well as X-ray diffraction analysis.
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Affiliation(s)
- Siuli Das
- Bioinspired Coordination Chemistry and Homogeneous Catalysis Group, Institute of Chemistry, Carl von Ossietzky University Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129, Oldenburg, Germany
| | - Julia Buschermöhle
- Bioinspired Coordination Chemistry and Homogeneous Catalysis Group, Institute of Chemistry, Carl von Ossietzky University Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129, Oldenburg, Germany
| | - Dirk W Zant
- van 't Hoff Institute for Molecular Sciences, University of Amsterdam, the, Netherlands
| | - M Schmidtmann
- Bioinspired Coordination Chemistry and Homogeneous Catalysis Group, Institute of Chemistry, Carl von Ossietzky University Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129, Oldenburg, Germany
| | - Jarl Ivar van der Vlugt
- Bioinspired Coordination Chemistry and Homogeneous Catalysis Group, Institute of Chemistry, Carl von Ossietzky University Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129, Oldenburg, Germany
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2
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Wojnar M, Ziller JW, Heyduk AF. Two-Electron Mixed Valency in a Heterotrimetallic Nickel-Vanadium-Nickel Complex. Inorg Chem 2023; 62:1405-1413. [PMID: 36633592 PMCID: PMC9890480 DOI: 10.1021/acs.inorgchem.2c03381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Mixed-valence complexes represent an enticing class of coordination compounds to interrogate electron transfer confined within a molecular framework. The diamagnetic heterotrimetallic anion, [V(SNS)2{Ni(dppe)}2]-, was prepared by reducing (dppe)NiCl2 in the presence of the chelating metalloligand [V(SNS)2]- [dppe = bis(diphenylphosphino)ethane; (SNS)3- = bis(2-thiolato-4-methylphenyl)amide]. Vanadium-nickel bonds span the heterotrimetallic core in the structure of [V(SNS)2{Ni(dppe)}2]-, with V-Ni bond lengths of 2.78 and 2.79 Å. One-electron oxidation of monoanionic [V(SNS)2{Ni(dppe)}2]- yielded neutral, paramagnetic V(SNS)2{Ni(dppe)}2. The solid-state structure of V(SNS)2{Ni(dppe)}2 revealed that the two nickel ions occupy unique coordination environments: one nickel is in a square-planar S2P2 coordination environment (τ4 = 0.19), with a long Ni···V distance of 3.45 Å; the other nickel is in a tetrahedral S2P2 coordination environment (τ4 = 0.84) with a short Ni-V distance of 2.60 Å, consistent with a formal metal-metal bond. Continuous-wave X-band electron paramagnetic resonance spectroscopy, electrochemical investigations, and density functional theory computations indicated that the unpaired electron in the neutral V(SNS)2{Ni(dppe)}2 cluster is localized on the bridging [V(SNS)2] metalloligand, and as a result, V(SNS)2{Ni(dppe)}2 is best described as a two-electron mixed-valence complex. These results demonstrate the important role that metal-metal interactions and flexible coordination geometries play in enabling multiple, reversible electron transfer processes in small cluster complexes.
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3
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Synthesis, characterization, electrochemical behavior, and catalytic activity of cobalt(II) metal complexes with pincer-type methylbenzamide derivative ligands. Polyhedron 2022. [DOI: 10.1016/j.poly.2022.115846] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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4
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Maleeva AV, Ershova IV, Trofimova OY, Arsenyeva KV, Yakushev IA, Piskunov AV. Near-IR absorbing donor–acceptor charge-transfer gallium complex, an example from non-transition metal chemistry. MENDELEEV COMMUNICATIONS 2022. [DOI: 10.1016/j.mencom.2022.01.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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5
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Role of a Redox-Active Ligand Close to a Dinuclear Activating Framework. TOP ORGANOMETAL CHEM 2022. [DOI: 10.1007/3418_2022_77] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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6
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Abstract
The nickel(II) complex [ON(H)O]Ni(PPh3) ([ON(H)O]2- = bis(3,5-di-tert-butyl-2-phenoxy)amine), bearing a protonated redox-active ligand, was examined for its ability to serve as a hydrogen atom (H•) and hydride (H-) donor. Deprotonation of [ON(H)O]Ni(PPh3) afforded the square-planar anion {[ONOcat]Ni(PPh3)}1-, whereas hydrogen atom transfer from [ON(H)O]Ni(PPh3) to TEMPO• in the presence of added PPh3 afforded five-coordinate [ONO]Ni(PPh3)2 that has been structurally characterized. In solution, this five-coordinate complex exists in equilibrium with four-coordinate [ONO]Ni(PPh3), and this ligand exchange equilibrium correlates with a valence tautomerization between the redox-active ligand and the nickel center. Abstraction of a hydride from [ON(H)O]Ni(PPh3) in the presence of PPh3 afforded the octahedral complex, [ONOq]Ni(OTf)(PPh3)2, which was characterized as an S = 1, nickel(II) complex. Bond dissociation free energy (BDFE) and hydricity (ΔG°H-) measurements benchmark the thermodynamic propensity of this complex to participate in ligand-centered H• and H- transfer reactions.
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Affiliation(s)
- Bronte J Charette
- Department of Chemistry, University of California, Irvine, Irvine, California 92677-2025, United States
| | - Joseph W Ziller
- Department of Chemistry, University of California, Irvine, Irvine, California 92677-2025, United States
| | - Alan F Heyduk
- Department of Chemistry, University of California, Irvine, Irvine, California 92677-2025, United States
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7
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Hofmann AJ, Jandl C, Hess CR. Structural Differences and Redox Properties of Unsymmetric Diiron PDIxCy Complexes. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.201901173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Andreas J. Hofmann
- Department of Chemistry and Catalysis Research Center Technische Universität München Lichtenbergstraße 4 85748 Garching Germany
| | - Christian Jandl
- Department of Chemistry and Catalysis Research Center Technische Universität München Lichtenbergstraße 4 85748 Garching Germany
| | - Corinna R. Hess
- Department of Chemistry and Catalysis Research Center Technische Universität München Lichtenbergstraße 4 85748 Garching Germany
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8
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van der Vlugt JI. Redox-Active Pincer Ligands. TOP ORGANOMETAL CHEM 2020. [DOI: 10.1007/3418_2020_68] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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9
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Biswas S, Lau N, Borovik AS, Hendrich MP, Bominaar EL. Analysis of the Puzzling Exchange-Coupling Constants in a Series of Heterobimetallic Complexes. Inorg Chem 2019; 58:9150-9160. [DOI: 10.1021/acs.inorgchem.9b00757] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Saborni Biswas
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Nathanael Lau
- Department of Chemistry, University of California−Irvine, 1102 Natural Sciences II, Irvine, California 92697, United States
| | - A. S. Borovik
- Department of Chemistry, University of California−Irvine, 1102 Natural Sciences II, Irvine, California 92697, United States
| | - Michael P. Hendrich
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Emile L. Bominaar
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
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van der Vlugt JI. Radical-Type Reactivity and Catalysis by Single-Electron Transfer to or from Redox-Active Ligands. Chemistry 2019; 25:2651-2662. [PMID: 30084211 PMCID: PMC6471147 DOI: 10.1002/chem.201802606] [Citation(s) in RCA: 127] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Indexed: 12/12/2022]
Abstract
Controlled ligand-based redox-activity and chemical non-innocence are rapidly gaining importance for selective (catalytic) processes. This Concept aims to provide an overview of the progress regarding ligand-to-substrate single-electron transfer as a relatively new mode of operation to exploit ligand-centered reactivity and catalysis based thereon.
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Affiliation(s)
- Jarl Ivar van der Vlugt
- Bio-Inspired Homogeneous and Supramolecular Catalysis Groupvan ‘t Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098 XHAmsterdamNetherlands
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11
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Lau N, Sano Y, Ziller JW, Borovik AS. Modular bimetallic complexes with a sulfonamido-based ligand. Dalton Trans 2018; 47:12362-12372. [PMID: 30118133 PMCID: PMC6165629 DOI: 10.1039/c8dt02455c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of bimetallic complexes prepared with the ligands N,N,N',N'-tetramethylethane-1,2-diamine (TMEDA) and N,N',N''-[2,2',2''-nitrilotris(ethane-2,1-diyl)]tris(2,4,6-trimethylbenzenesulfonamido) ([MST]3-) is described. Four diiron compounds of the formulation (TMEDA)FeII(X)-(μ-OH)-FeIIIMST were prepared, in which the X- ligands are the anions OTf-, Br-, SCN-, or N3-. Additionally, two heterobimetallic compounds of the formulation (TMEDA)MII(OTf)-(μ-OH)-FeIIIMST (MII = CoII or NiII) were synthesized. All these compounds have similar spectroscopic and structural properties. The diiron compounds exhibit perpendicular-mode electron paramagnetic resonance spectra consistent with S = 1/2 spin ground states, which is expected for high-spin FeII and FeIII centres that are antiferromagnetically coupled. The heterobimetallic (TMEDA)NiII(OTf)-(μ-OH)-FeIIIMST complex had a spin state of S = 3/2 that also resulted from antiferromagnetic coupling between the high-spin NiII and FeIII centres. The modularity of this system is further demonstrated by the substitution of the TMEDA ligand with ethylenediamine (en); for this species two equivalents of en coordinate to the FeII centre to form [(en)2FeII-(μ-OH)-FeIIIMST]OTf. These results demonstrate that a modular bimetallic system has been developed in which the key components can be modified.
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Affiliation(s)
- Nathanael Lau
- Department of Chemistry, University of California - Irvine, 1102 Natural Sciences II, Irvine, CA 92697-2025, USA.
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12
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Chang MC, McNeece AJ, Hill EA, Filatov AS, Anderson JS. Ligand-Based Storage of Protons and Electrons in Dihydrazonopyrrole Complexes of Nickel. Chemistry 2018; 24:8001-8008. [PMID: 29572998 DOI: 10.1002/chem.201800658] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Indexed: 12/24/2022]
Abstract
A newly developed dihydrazonopyrrole ligand and corresponding Ni complexes have been synthesized and thoroughly characterized. Electrochemical studies and chemical reactivity tests show that these complexes can reversibly store both electrons and protons, or equivalently H-atoms, via ligand-based events. The stored H-atom equivalent can be transferred to small molecules such as acetonitrile or oxygen. Furthermore, this series of complexes can adopt a variety of different coordination modes. In addition to one e- reactivity, the two e- electrophilic oxidation of phosphines is also demonstrated. Taken together, these results show that dihydrazonopyrrole complexes represent a geometrically and electronically flexible scaffold for controlling the flow of both electrons and protons.
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Affiliation(s)
- Mu-Chieh Chang
- Department of Chemistry, The University of Chicago, Chicago, 5735 S Ellis Ave, Chicago, IL, 60637, USA
| | - Andrew J McNeece
- Department of Chemistry, The University of Chicago, Chicago, 5735 S Ellis Ave, Chicago, IL, 60637, USA
| | - Ethan A Hill
- Department of Chemistry, The University of Chicago, Chicago, 5735 S Ellis Ave, Chicago, IL, 60637, USA
| | - Alexander S Filatov
- Department of Chemistry, The University of Chicago, Chicago, 5735 S Ellis Ave, Chicago, IL, 60637, USA
| | - John S Anderson
- Department of Chemistry, The University of Chicago, Chicago, 5735 S Ellis Ave, Chicago, IL, 60637, USA
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13
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Clarke RM, Jeen T, Rigo S, Thompson JR, Kaake LG, Thomas F, Storr T. Exploiting exciton coupling of ligand radical intervalence charge transfer transitions to tune NIR absorption. Chem Sci 2017; 9:1610-1620. [PMID: 29675206 PMCID: PMC5887452 DOI: 10.1039/c7sc04537a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 12/18/2017] [Indexed: 12/03/2022] Open
Abstract
We detail the rational design of a series of bimetallic bis-ligand radical Ni salen complexes in which the relative orientation of the ligand radical chromophores provides a mechanism to tune the energy of intense intervalence charge transfer (IVCT) bands in the near infrared (NIR) region.
We detail the rational design of a series of bimetallic bis-ligand radical Ni salen complexes in which the relative orientation of the ligand radical chromophores provides a mechanism to tune the energy of intense intervalence charge transfer (IVCT) bands in the near infrared (NIR) region. Through a suite of experimental (electrochemistry, electron paramagnetic resonance spectroscopy, UV-vis-NIR spectroscopy) and theoretical (density functional theory) techniques, we demonstrate that bimetallic Ni salen complexes form bis-ligand radicals upon two-electron oxidation, whose NIR absorption energies depend on the geometry imposed in the bis-ligand radical complex. Relative to the oxidized monomer [1˙]+ (E = 4500 cm–1, ε = 27 700 M–1 cm–1), oxidation of the cofacially constrained analogue 2 to [2˙˙]2+ results in a blue-shifted NIR band (E = 4830 cm–1, ε = 42 900 M–1 cm–1), while oxidation of 5 to [5˙˙]2+, with parallel arrangement of chromophores, results in a red-shifted NIR band (E = 4150 cm–1, ε = 46 600 M–1 cm–1); the NIR bands exhibit double the intensity in comparison to the monomer. Oxidation of the intermediate orientations results in band splitting for [3˙˙]2+ (E = 4890 and 4200 cm–1; ε = 26 500 and 21 100 M–1 cm–1), and a red-shift for [4˙˙]2+ using ortho- and meta-phenylene linkers, respectively. This study demonstrates for the first time, the applicability of exciton coupling to ligand radical systems absorbing in the NIR region and shows that by simple geometry changes, it is possible to tune the energy of intense low energy absorption by nearly 400 nm.
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Affiliation(s)
- Ryan M Clarke
- Department of Chemistry , Simon Fraser University , V5A1S6 , Burnaby , BC , Canada .
| | - Tiffany Jeen
- Department of Chemistry , Simon Fraser University , V5A1S6 , Burnaby , BC , Canada .
| | - Serena Rigo
- Department of Chemistry , Simon Fraser University , V5A1S6 , Burnaby , BC , Canada .
| | - John R Thompson
- Department of Chemistry , Simon Fraser University , V5A1S6 , Burnaby , BC , Canada .
| | - Loren G Kaake
- Department of Chemistry , Simon Fraser University , V5A1S6 , Burnaby , BC , Canada .
| | - Fabrice Thomas
- Départment de Chimie Moléculaire - Chimie Inorganique Redox (CIRE) - UMR CNRS 5250 , Université Grenoble-Alpes , B.P. 53 , 38041 Grenoble Cedex 9 , France
| | - Tim Storr
- Department of Chemistry , Simon Fraser University , V5A1S6 , Burnaby , BC , Canada .
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14
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Sano Y, Lau N, Weitz AC, Ziller JW, Hendrich MP, Borovik A. Models for Unsymmetrical Active Sites in Metalloproteins: Structural, Redox, and Magnetic Properties of Bimetallic Complexes with M II-(μ-OH)-Fe III Cores. Inorg Chem 2017; 56:14118-14128. [PMID: 29112385 PMCID: PMC5696092 DOI: 10.1021/acs.inorgchem.7b02230] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Bimetallic complexes are important sites in metalloproteins but are often difficult to prepare synthetically. We have previously introduced an approach to form discrete bimetallic complexes with MII-(μ-OH)-FeIII (MII = Mn, Fe) cores using the tripodal ligand N,N',N″-[2,2',2″-nitrilotris(ethane-2,1-diyl)]tris(2,4,6-trimethylbenzenesulfonamido) ([MST]3-). This series is extended to include the rest of the late 3d transition metal ions (MII = Co, Ni, Cu, Zn). All of the bimetallic complexes have similar spectroscopic and structural properties that reflect little change despite varying the MII centers. Magnetic studies performed on the complexes in solution using electron paramagnetic resonance spectroscopy showed that the observed spin states varied incrementally from S = 0 through S = 5/2; these results are consistent with antiferromagnetic coupling between the high-spin MII and FeIII centers. However, the difference in the MII ion occupancy yielded only slight changes in the magnetic exchange coupling strength, and all complexes had J values ranging from +26(4) to +35(3) cm-1.
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Affiliation(s)
- Yohei Sano
- Department of Chemistry, University of California – Irvine, 1102 Natural Sciences II, Irvine, CA 92697-2025, United States
| | - Nathanael Lau
- Department of Chemistry, University of California – Irvine, 1102 Natural Sciences II, Irvine, CA 92697-2025, United States
| | - Andrew C. Weitz
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213, United States
| | - Joseph W. Ziller
- Department of Chemistry, University of California – Irvine, 1102 Natural Sciences II, Irvine, CA 92697-2025, United States
| | - Michael P. Hendrich
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213, United States
| | - A.S. Borovik
- Department of Chemistry, University of California – Irvine, 1102 Natural Sciences II, Irvine, CA 92697-2025, United States
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15
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Mondal S, Bera S, Maity S, Ghosh P. Cobalt Ion Promoted Redox Cascade: A Route to Spiro Oxazine-Oxazepine Derivatives and a Dinuclear Cobalt(III) Complex of an N-(1,4-Naphthoquinone)-o-aminophenol Derivative. Inorg Chem 2017; 56:13194-13204. [PMID: 29035522 DOI: 10.1021/acs.inorgchem.7b01961] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The study discloses that the redox activity of N-(1,4-naphthoquinone)-o-aminophenol derivatives (LRH2) containing a (phenol)-NH-(1,4-naphthoquinone) fragment is notably different from that of a (phenol)-NH-(phenol) precursor. The former is a platform for a redox cascade. LRH2 is redox noninnocent and exists in Cat-N-(1,4-naphthoquinone)(2-) (LR 2-) and SQ-N-(1,4-naphthoquinone) (LR •-) states in the complexes. Reactions of LRH2 with cobalt(II) salts in MeOH in air promote a cascade affording spiro oxazine-oxazepine derivatives (OXLR) in good yields, when R = H, Me, tBu. Spiro oxazine-oxazepine derivatives are bioactive, and such a molecule has so far not been isolated by a schematic route. In this context this cascade is significant. Dimerization of LRH2 → OXLR in MeOH is a (6H+ + 6e) oxidation reaction and is composed of formations of four covalent bonds and 6-exo-trig and 7-endo-trig cyclization based on C-O coupling reactions, where MeOH is the source of a proton and the ester function. It was established that the active cascade precursor is [(LMe •-)CoIIICl2] (A). Notably, formation of a spiro derivative was not detected in CH3CN and the reaction ends up furnishing A. The route of the reaction is tunable by R, when R = NO2, it is a (2e + 4H+) oxidation reaction affording a dinuclear LR 2- complex of cobalt(III) of the type [(LNO2 2-)2CoIII2(OMe)2(H2O)2] (1) in good yields. No cascade occurs with zinc(II) ion even in MeOH and produces a LMe •- complex of type [(LMe •-)ZnIICl2] (2). The intermediate A and 2 exhibit strong EPR signals at g = 2.008 and 1.999, confrming the existence of LMe •- coordinated to low-spin cobalt(III) and zinc(II) ions. The intermediates of LRH2 → OXLR conversion were analyzed by ESI mass spectrometry. The molecular geometries of OXLR and 1 were confirmed by X-ray crystallography, and the spectral features were elucidated by TD DFT calculations.
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Affiliation(s)
- Sandip Mondal
- Department of Chemistry, R. K. Mission Residential College, Narendrapur , Kolkata 103, West Bengal, India
| | - Sachinath Bera
- Department of Chemistry, R. K. Mission Residential College, Narendrapur , Kolkata 103, West Bengal, India
| | - Suvendu Maity
- Department of Chemistry, R. K. Mission Residential College, Narendrapur , Kolkata 103, West Bengal, India
| | - Prasanta Ghosh
- Department of Chemistry, R. K. Mission Residential College, Narendrapur , Kolkata 103, West Bengal, India
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16
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Bagh B, Broere DL, Sinha V, Kuijpers PF, van Leest NP, de Bruin B, Demeshko S, Siegler MA, van der Vlugt JI. Catalytic Synthesis of N-Heterocycles via Direct C(sp 3)-H Amination Using an Air-Stable Iron(III) Species with a Redox-Active Ligand. J Am Chem Soc 2017; 139:5117-5124. [PMID: 28298089 PMCID: PMC5391503 DOI: 10.1021/jacs.7b00270] [Citation(s) in RCA: 150] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Indexed: 12/23/2022]
Abstract
Coordination of FeCl3 to the redox-active pyridine-aminophenol ligand NNOH2 in the presence of base and under aerobic conditions generates FeCl2(NNOISQ) (1), featuring high-spin FeIII and an NNOISQ radical ligand. The complex has an overall S = 2 spin state, as deduced from experimental and computational data. The ligand-centered radical couples antiferromagnetically with the Fe center. Readily available, well-defined, and air-stable 1 catalyzes the challenging intramolecular direct C(sp3)-H amination of unactivated organic azides to generate a range of saturated N-heterocycles with the highest turnover number (TON) (1 mol% of 1, 12 h, TON = 62; 0.1 mol% of 1, 7 days, TON = 620) reported to date. The catalyst is easily recycled without noticeable loss of catalytic activity. A detailed kinetic study for C(sp3)-H amination of 1-azido-4-phenylbutane (S1) revealed zero order in the azide substrate and first order in both the catalyst and Boc2O. A cationic iron complex, generated from the neutral precatalyst upon reaction with Boc2O, is proposed as the catalytically active species.
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Affiliation(s)
- Bidraha Bagh
- Homogeneous,
Bioinspired and Supramolecular Catalysis, van’t Hoff Institute
for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Daniël L.
J. Broere
- Homogeneous,
Bioinspired and Supramolecular Catalysis, van’t Hoff Institute
for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Vivek Sinha
- Homogeneous,
Bioinspired and Supramolecular Catalysis, van’t Hoff Institute
for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Petrus F. Kuijpers
- Homogeneous,
Bioinspired and Supramolecular Catalysis, van’t Hoff Institute
for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Nicolaas P. van Leest
- Homogeneous,
Bioinspired and Supramolecular Catalysis, van’t Hoff Institute
for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Bas de Bruin
- Homogeneous,
Bioinspired and Supramolecular Catalysis, van’t Hoff Institute
for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Serhiy Demeshko
- Institüt
für Anorganische Chemie, Georg-August-Universität
Göttingen, Tammannstraße
4, 37077 Göttingen, Germany
| | - Maxime A. Siegler
- Small
Molecule X-ray Crystallography, Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Jarl Ivar van der Vlugt
- Homogeneous,
Bioinspired and Supramolecular Catalysis, van’t Hoff Institute
for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
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17
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Maity S, Kundu S, Mondal S, Bera S, Ghosh P. Molecular and Electronic Structures of Ruthenium Complexes Containing an ONS-Coordinated Open-Shell π Radical and an Oxidative Aromatic Ring Cleavage Reaction. Inorg Chem 2017; 56:3363-3376. [DOI: 10.1021/acs.inorgchem.6b02862] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Suvendu Maity
- Department of Chemistry, R. K. Mission Residential College, Narendrapur, Kolkata 103, India
| | - Suman Kundu
- Department of Chemistry, R. K. Mission Residential College, Narendrapur, Kolkata 103, India
| | - Sandip Mondal
- Department of Chemistry, R. K. Mission Residential College, Narendrapur, Kolkata 103, India
| | - Sachinath Bera
- Department of Chemistry, R. K. Mission Residential College, Narendrapur, Kolkata 103, India
| | - Prasanta Ghosh
- Department of Chemistry, R. K. Mission Residential College, Narendrapur, Kolkata 103, India
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18
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Rosenkoetter KE, Ziller JW, Heyduk AF. Heterobimetallic complexes of palladium and platinum containing a redox-active W[SNS]2 metalloligand. Dalton Trans 2017; 46:5503-5507. [DOI: 10.1039/c6dt04451d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Heterobimetallic W–Pd and W–Pt complexes have been prepared using the redox-active W(SNS)2 metalloligand.
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Affiliation(s)
| | | | - Alan F. Heyduk
- Department of Chemistry
- University of California
- Irvine
- USA
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19
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Kiernicki JJ, Higgins RF, Kraft SJ, Zeller M, Shores MP, Bart SC. Elucidating the Mechanism of Uranium Mediated Diazene N═N Bond Cleavage. Inorg Chem 2016; 55:11854-11866. [PMID: 27805393 DOI: 10.1021/acs.inorgchem.6b01922] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Investigation into the reactivity of reduced uranium species toward diazenes has revealed key intermediates in the four-electron cleavage of azobenzene. Trivalent Tp*2U(CH2Ph) (1a) (Tp* = hydrotris(3,5-dimethylpyrazolyl)borate) and Tp*2U(2,2'-bpy) (1b) both perform the two-electron reduction of diazenes affording η2-hydrazido complexes Tp*2U(AzBz) (2-AzBz) (AzBz = azobenzene) and Tp*2U(BCC) (2-BCC) (BCC = benzo[c]cinnoline) in contrast to precursors of the bis(Cp*) (Cp* = 1,2,3,4,5-pentamethylcyclopentadienide) ligand framework. The four-electron cleavage of diazenes to give trans-bis(imido) species was possible by using Cp*U(MesPDIMe)(THF) (3) (MesPDIMe = 2,6-((Mes)N═CMe)2-C5H3N, Mes = 2,4,6-trimethylphenyl), which is supported by a highly reduced trianionic chelate that undergoes electron transfer. This proceeds via concerted addition at a single uranium center supported by both a crossover experiment and through addition of an asymmetrically substituted diazene, Ph-N═N-Tol. Further investigation of 3 and its substituted analogue, Cp*U(tBu-MesPDIMe)(THF) (3-tBu) (tBu-MesPDIMe = 2,6-((Mes)N═CMe)2-p-C(CH3)3-C5H2N), with benzo[c]cinnoline, revealed that the four-electron cleavage occurs first by a single electron reduction of the diazene with the redox chemistry performed solely at the redox-active pyridine(diimine) to form dimeric [Cp*U(BCC)(MesHPDIMe)]2 (5) and Cp*U(BCC)(tBu-MesPDIMe) (6). While a transient pyridine(diimine) triplet diradical in the formation of 5 results in H atom abstraction and p-pyridine coupling, the tert-butyl moiety in 6 allows for electronic rearrangement to occur, precluding deleterious pyridine-radical coupling. The monomeric analogue of 5, Cp*U(BCC)(MesPDIMe) (7), was synthesized via salt metathesis from Cp*UI(MesPDIMe) (3-I). All complexes have been characterized by 1H NMR and electronic absorption spectroscopies, X-ray diffraction, and, where pertinent, EPR spectroscopy. Further, the electronic structures of 3-I, 5, and 7 have been investigated by SQUID magnetometry.
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Affiliation(s)
- John J Kiernicki
- H.C. Brown Laboratory, Department of Chemistry, Purdue University , West Lafayette, Indiana 47906, United States
| | - Robert F Higgins
- Department of Chemistry, Colorado State University , Fort Collins, Colorado 80523, United States
| | - Steven J Kraft
- H.C. Brown Laboratory, Department of Chemistry, Purdue University , West Lafayette, Indiana 47906, United States
| | - Matthias Zeller
- H.C. Brown Laboratory, Department of Chemistry, Purdue University , West Lafayette, Indiana 47906, United States
| | - Matthew P Shores
- Department of Chemistry, Colorado State University , Fort Collins, Colorado 80523, United States
| | - Suzanne C Bart
- H.C. Brown Laboratory, Department of Chemistry, Purdue University , West Lafayette, Indiana 47906, United States
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20
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Maity S, Kundu S, Bera S, Weyhermüller T, Ghosh P. Mixed‐Valence o‐Iminobenzoquinone and o‐Iminobenzosemiquinonate Anion Radical Complexes of Cobalt: Valence Tautomerism. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201600525] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Suvendu Maity
- Department of ChemistryR. K. Mission Residential CollegeKolkata‐103NarendrapurIndia
| | - Suman Kundu
- Department of ChemistryR. K. Mission Residential CollegeKolkata‐103NarendrapurIndia
| | - Sachinath Bera
- Department of ChemistryR. K. Mission Residential CollegeKolkata‐103NarendrapurIndia
| | - Thomas Weyhermüller
- Max‐Planck‐Institut für Chemische EnergiekonversionStiftstrasse 34–3645470Mülheim an der RuhrGermany
| | - Prasanta Ghosh
- Department of ChemistryR. K. Mission Residential CollegeKolkata‐103NarendrapurIndia
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21
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Sil D, Kumar A, Rath SP. Diiron(III)-μ-Fluoro Bisporphyrins: Effect of Bridging Ligand on the Metal Spin State. Chemistry 2016; 22:11214-23. [DOI: 10.1002/chem.201600786] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Indexed: 11/08/2022]
Affiliation(s)
- Debangsu Sil
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur- 208016 India
| | - Amit Kumar
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur- 208016 India
| | - Sankar Prasad Rath
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur- 208016 India
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22
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Rosenkoetter KE, Ziller JW, Heyduk AF. A Heterobimetallic W-Ni Complex Containing a Redox-Active W[SNS]2 Metalloligand. Inorg Chem 2016; 55:6794-8. [PMID: 27300501 DOI: 10.1021/acs.inorgchem.6b01164] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The tungsten complex W[SNS]2 ([SNS]H3 = bis(2-mercapto-4-methylphenyl)amine) was bound to a Ni(dppe) [dppe = 1,2-bis(diphenylphosphino)ethane] fragment to form the new heterobimetallic complex W[SNS]2Ni(dppe). Characterization of the complex by single-crystal X-ray diffraction revealed the presence of a short W-Ni bond, which renders the complex diamagnetic despite formal tungsten(V) and nickel(I) oxidation states. The W[SNS]2 unit acts as a redox-active metalloligand in the bimetallic complex, which displays four one-electron redox processes by cyclic voltammetry. In the presence of the organic acid 4-cyanoanilinium tetrafluoroborate, W[SNS]2Ni(dppe) catalyzes the electrochemical reduction of protons to hydrogen coincident with the first reduction of the complex.
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Affiliation(s)
- Kyle E Rosenkoetter
- Department of Chemistry, University of California , 1102 Natural Sciences 2, Irvine, California 92677, United States
| | - Joseph W Ziller
- Department of Chemistry, University of California , 1102 Natural Sciences 2, Irvine, California 92677, United States
| | - Alan F Heyduk
- Department of Chemistry, University of California , 1102 Natural Sciences 2, Irvine, California 92677, United States
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