1
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León F, García-Rodeja Y, Mallet-Ladeira S, Miqueu K, Szalóki G, Bourissou D. Catechol/ o-benzoquinone exchange at gold(iii). Chem Sci 2024:d4sc04374j. [PMID: 39309082 PMCID: PMC11414447 DOI: 10.1039/d4sc04374j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2024] [Accepted: 09/15/2024] [Indexed: 09/25/2024] Open
Abstract
Although gold(iii) chemistry has tremendously progressed in the past 2 decades, gold(iii) catecholate complexes remain extremely scarce and underdeveloped. Upon preparation and full characterization of P^C-cyclometalated gold(iii) complexes, we serendipitously uncovered an intriguing catechol exchange process at gold(iii). Electron-rich catecholates turned out to be readily displaced by electron-poor o-benzoquinones. DFT calculations revealed an original path for this transformation involving two consecutive Single Electron Transfer events between the catecholate and o-benzoquinone moieties while gold maintains its +III oxidation state. This catechol/o-benzoquinone exchange at gold(iii) represents a new path for the exchange of X-type ligands at transition metals.
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Affiliation(s)
- Félix León
- CNRS/Université Paul Sabatier, Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA, UMR 5069) 118 Route de Narbonne 31062 Toulouse Cedex 09 France
| | - Yago García-Rodeja
- CNRS/Université de Pau et des Pays de l'Adour. E2S-UPPA, Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et les Matériaux (IPREM, UMR 5254), Hélioparc 2 Avenue du Président Angot 64053 Pau Cedex 09 France
| | - Sonia Mallet-Ladeira
- Institut de Chimie de Toulouse (UAR 2599) 118 Route de Narbonne 31062 Toulouse Cedex 09 France
| | - Karinne Miqueu
- CNRS/Université de Pau et des Pays de l'Adour. E2S-UPPA, Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et les Matériaux (IPREM, UMR 5254), Hélioparc 2 Avenue du Président Angot 64053 Pau Cedex 09 France
| | - György Szalóki
- CNRS/Université Paul Sabatier, Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA, UMR 5069) 118 Route de Narbonne 31062 Toulouse Cedex 09 France
| | - Didier Bourissou
- CNRS/Université Paul Sabatier, Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA, UMR 5069) 118 Route de Narbonne 31062 Toulouse Cedex 09 France
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2
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González JA, Arribas A, Tian P, Díaz-Alonso S, Mascareñas JL, López F, Nevado C. Gold(III) Auracycles Featuring C(sp 3)-Au-C(sp 2) Bonds: Synthesis and Mechanistic Insights into the Cycloauration Step. Angew Chem Int Ed Engl 2024; 63:e202402798. [PMID: 38776235 DOI: 10.1002/anie.202402798] [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: 02/07/2024] [Revised: 04/19/2024] [Accepted: 05/22/2024] [Indexed: 05/24/2024]
Abstract
The direct auration of arenes is a key step in numerous gold-catalyzed reactions. Although reported more than 100 years ago, understanding of its underlying mechanism has been hampered by the difficulties in the isolation of relevant intermediates given the propensity of gold(III) species to undergo reductive elimination. Here, we report the synthesis and isolation of a new family of intriguing zwitterionic [C(sp3)^C(sp2)]-auracyclopentanes, as well as of their alkyl-gold(III) precursors and demonstrate their value as mechanistic probes to study the C(sp2)-Au bond-forming event. Experimental investigations employing Kinetic Isotope Effects (KIE), Hammett plot, and Eyring analysis provided important insights into the formation of the auracycle. The data suggest a SEAr mechanism wherein the slowest step might be the π-coordination between the arene and the gold(III) center, en route to the Wheland intermediate. We also show that these auracyclopentanes can work as catalysts in several gold-promoted transformations.
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Affiliation(s)
- Jorge A González
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, 8057, Zürich, Switzerland
| | - Andrés Arribas
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS) and Departamento de Química Orgánica, Universidade de Santiago de Compostela, 15782, Santiago de Compostela, Spain
| | - Puyang Tian
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, 8057, Zürich, Switzerland
| | - Sergio Díaz-Alonso
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS) and Departamento de Química Orgánica, Universidade de Santiago de Compostela, 15782, Santiago de Compostela, Spain
| | - José Luis Mascareñas
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS) and Departamento de Química Orgánica, Universidade de Santiago de Compostela, 15782, Santiago de Compostela, Spain
| | - Fernando López
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS) and Departamento de Química Orgánica, Universidade de Santiago de Compostela, 15782, Santiago de Compostela, Spain
- Misión Biológica de Galicia, Consejo Superior de Investigaciones Científicas (CSIC), 36680, Pontevedra, Spain
| | - Cristina Nevado
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, 8057, Zürich, Switzerland
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3
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Font P, Valdés H, Ribas X. Consolidation of the Oxidant-Free Au(I)/Au(III) Catalysis Enabled by the Hemilabile Ligand Strategy. Angew Chem Int Ed Engl 2024; 63:e202405824. [PMID: 38687322 DOI: 10.1002/anie.202405824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Revised: 04/29/2024] [Accepted: 04/30/2024] [Indexed: 05/02/2024]
Abstract
In this minireview we survey the challenges and strategies in gold redox catalysis. Gold's reluctance to oxidative addition reactions due to its high redox potential limits its applicability. Initial attempts to overcome this problem focused on the use of sacrificial external oxidants in stoichiometric amounts to bring Au(I) compounds to Au(III) reactive species. Recently, innovative approaches focused on employing hemilabile ligands, which are capable of coordinating to Au(I) and stabilizing square-planar Au(III) intermediates, thus facilitating oxidative addition steps and enabling oxidant-free catalysis. Notable examples include the use of the (P^N) bidendate MeDalphos ligand to achieve various cross-coupling reactions via oxidative addition Au(I)/Au(III). Importantly, hemilabile ligand-enabled catalysis allows merging oxidative addition with π-activation, such as oxy- and aminoarylation of alkenols and alkenamines using organohalides, expanding gold's versatility in C-C and C-heteroatom bond formations and unprecedented cyclizations. Moreover, recent advancements in enantioselective catalysis using chiral hemilabile (P^N) ligands are also surveyed. Strikingly, versatile bidentate (C^N) hemilabile ligands as competitors of MeDalphos have appeared recently, by designing scaffolds where phosphine groups are substituted by N-heterocyclic or mesoionic carbenes. Overall, these approaches highlight the evolving landscape of gold redox catalysis and its tremendous potential in a broad scope of transformations.
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Affiliation(s)
- Pau Font
- Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona, Campus de Montilivi, Girona, E-17003, Catalonia, Spain
| | - Hugo Valdés
- Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona, Campus de Montilivi, Girona, E-17003, Catalonia, Spain
- Current address: Departamento de Química Orgánica y Química Inorgánica, Universidad de Alcalá, 28805, Alcalá de Henares, Madrid, Spain
| | - Xavi Ribas
- Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona, Campus de Montilivi, Girona, E-17003, Catalonia, Spain
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4
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Martín J, Schörgenhumer J, Biedrzycki M, Nevado C. (P^N^C) Ligands to Stabilize Gold(III): A Straightforward Access to Hydroxo, Formate, and Hydride Complexes. Inorg Chem 2024; 63:8390-8396. [PMID: 38657169 PMCID: PMC11080065 DOI: 10.1021/acs.inorgchem.4c00788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 04/09/2024] [Accepted: 04/10/2024] [Indexed: 04/26/2024]
Abstract
A novel class of (P^N^C) pincer ligands capable of stabilizing elusive gold(III) species is reported here. Straightforward access to (P^N^C)gold(III) hydroxo, formate, and hydride complexes has been streamlined by first incorporating a cycloauration step devoid of toxic metals or harsh conditions. The resulting gold complexes exhibit remarkable stability in solution as well as in the solid state under ambient conditions, which enabled their characterization by X-ray diffraction analyses. Interestingly, the influence of the ligand allowed the preparation of gold(III)-hydrides using mild hydride donors such as H-Bpin, which contrasts with sensitive super hydrides or strong acids and cryogenic conditions employed in previous protocols. A detailed bonding characterization of these species is complemented by reactivity studies.
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Affiliation(s)
- Jaime Martín
- Department of Chemistry, University
of Zurich, Winterthurerstrasse 190, Zurich, CH 8057, Switzerland
| | - Johannes Schörgenhumer
- Department of Chemistry, University
of Zurich, Winterthurerstrasse 190, Zurich, CH 8057, Switzerland
| | - Michał Biedrzycki
- Department of Chemistry, University
of Zurich, Winterthurerstrasse 190, Zurich, CH 8057, Switzerland
| | - Cristina Nevado
- Department of Chemistry, University
of Zurich, Winterthurerstrasse 190, Zurich, CH 8057, Switzerland
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5
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Vesseur D, Li S, Mallet-Ladeira S, Miqueu K, Bourissou D. Ligand-Enabled Oxidative Fluorination of Gold(I) and Light-Induced Aryl-F Coupling at Gold(III). J Am Chem Soc 2024. [PMID: 38607393 DOI: 10.1021/jacs.4c00913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2024]
Abstract
MeDalphos Au(I) complexes featuring aryl, alkynyl, and alkyl groups readily react with electrophilic fluorinating reagents such as N-fluorobenzenesulfonimide and Selectfluor. The ensuing [(MeDalphos)Au(R)F]+ complexes have been isolated and characterized by multinuclear NMR spectroscopy as well as X-ray diffraction. They adopt a square-planar contra-thermodynamic structure, with F trans to N. DFT/IBO calculations show that the N lone pair of MeDalphos assists and directs the transfer of F+ to gold. The [(MeDalphos)Au(Ar)F]+ (Ar = Mes, 2,6-F2Ph) complexes smoothly engage in C-C cross-coupling with PhCCSiMe3 and Me3SiCN, providing direct evidence for the oxidative fluorination/transmetalation/reductive elimination sequence proposed for F+-promoted gold-catalyzed transformations. Moreover, direct reductive elimination to forge a C-F bond at Au(III) was explored and substantiated. Thermal means proved unsuccessful, leading mostly to decomposition, but irradiation with UV-visible light enabled efficient promotion of aryl-F coupling (up to 90% yield). The light-induced reductive elimination proceeds under mild conditions; it works even with the electron-deprived 2,6-difluorophenyl group, and it is not limited to the contra-thermodynamic form of the aryl Au(III) fluoride complexes.
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Affiliation(s)
- David Vesseur
- Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA, UMR 5069) , CNRS/Université Paul Sabatier , 118 Route de Narbonne, 31062 Toulouse, Cedex 09, France
| | - Shuo Li
- Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA, UMR 5069) , CNRS/Université Paul Sabatier , 118 Route de Narbonne, 31062 Toulouse, Cedex 09, France
| | - Sonia Mallet-Ladeira
- Institut de Chimie de Toulouse (UAR 2599) , 118 Route de Narbonne, 31062 Toulouse, Cedex 09, France
| | - Karinne Miqueu
- E2S-UPPA, Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et les Matériaux (IPREM, UMR 5254), CNRS/Université de Pau et des Pays de l'Adour, Hélioparc, 2 Avenue du Président Angot, 64053 Pau, Cedex 09, France
| | - Didier Bourissou
- Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA, UMR 5069) , CNRS/Université Paul Sabatier , 118 Route de Narbonne, 31062 Toulouse, Cedex 09, France
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6
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Muratov K, Zaripov E, Berezovski MV, Gagosz F. DFT-Enabled Development of Hemilabile (P ∧N) Ligands for Gold(I/III) RedOx Catalysis: Application to the Thiotosylation of Aryl Iodides. J Am Chem Soc 2024; 146:3660-3674. [PMID: 38315643 DOI: 10.1021/jacs.3c08943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Abstract
Ligand-enabled oxidative addition of Csp2-X bonds to Au(I) centers has recently appeared as a valuable strategy for the development of catalytic RedOx processes. Several cross-coupling reactions that were previously considered difficult to achieve were reported lately, thus expanding the synthetic potential of gold(I) complexes beyond the traditional nucleophilic functionalization of π-systems. MeDalPhos has played an important role in this development and, despite several studies on alternative structures, remains, so far, the only general ligand for such process. We report herein the discovery and DFT-enabled structural optimization of a new family of hemilabile (P∧N) ligands that can promote the oxidative addition of aryl iodides to gold(I). These flexible ligands, which possess a common 2-methylamino heteroaromatic N-donor motif, are structurally and electronically tunable, beyond being easily accessible and affordable. The corresponding Au(I) complexes were shown to outperform the reactivity of (MeDalPhos)Au(I) in a series of alkoxy- and amidoarylations of alkenes. Their synthetic potential and comparatively higher reactivity were further highlighted in the thiotosylation of aryl iodides, a challenging unreported C-S cross-coupling reaction that could not be achieved under classical Pd(0/II) catalysis and that allows for general and divergent access to aryl sulfur derivatives.
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Affiliation(s)
- Karim Muratov
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa K1N 6N5, Canada
| | - Emil Zaripov
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa K1N 6N5, Canada
| | - Maxim V Berezovski
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa K1N 6N5, Canada
| | - Fabien Gagosz
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa K1N 6N5, Canada
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7
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Shiri F, Ho CC, Bissember AC, Ariafard A. Advancing Gold Redox Catalysis: Mechanistic Insights, Nucleophilicity-Guided Transmetalation, and Predictive Frameworks for the Oxidation of Aryl Gold(I) Complexes. Chemistry 2024; 30:e202302990. [PMID: 37967304 DOI: 10.1002/chem.202302990] [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: 09/14/2023] [Indexed: 11/17/2023]
Abstract
Gold redox catalysis, often facilitated by hypervalent iodine(III) reagents, offers unique reactivity but its progress is mainly hindered by an incomplete mechanistic understanding. In this study, we investigated the reaction between the gold(I) complexes [(aryl)Au(PR3 )] and the hypervalent iodine(III) reagent PhICl2 , both experimentally and computationally and provided an explanation for the formation of divergent products as the ligands bonded to the gold(I) center change. We tackled this essential question by uncovering an intriguing transmetalation mechanism that takes place between gold(I) and gold(III) complexes. We found that the ease of transmetalation is governed by the nucleophilicity of the gold(I) complex, [(aryl)Au(PR3 )], with greater nucleophilicity leading to a lower activation energy barrier. Remarkably, transmetalation is mainly controlled by a single orbital - the gold dx 2 -y 2 orbital. This orbital also has a profound influence on the reactivity of the oxidative addition step. In this way, the fundamental mechanistic basis of divergent outcomes in reactions of aryl gold(I) complexes with PhICl2 was established and these observations are reconciled from first principles. The theoretical model developed in this study provides a conceptual framework for anticipating the outcomes of reactions involving [(aryl)Au(PR3 )] with PhICl2 , thereby establishing a solid foundation for further advancements in this field.
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Affiliation(s)
- Farshad Shiri
- Department of Chemistry, Islamic Azad University, Central Tehran Branch, Poonak, Tehran, Iran
| | - Curtis C Ho
- School of Natural Sciences - Chemistry, University of Tasmania, Hobart, Tasmania, 7001, Australia
| | - Alex C Bissember
- School of Natural Sciences - Chemistry, University of Tasmania, Hobart, Tasmania, 7001, Australia
| | - Alireza Ariafard
- Research School of Chemistry, Australian National University, Canberra, ACT, 2601, Australia
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8
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Holmsen MSM, Nova A, Tilset M. Cyclometalated (N,C) Au(III) Complexes: The Impact of Trans Effects on Their Synthesis, Structure, and Reactivity. Acc Chem Res 2023; 56:3654-3664. [PMID: 38051910 PMCID: PMC10734256 DOI: 10.1021/acs.accounts.3c00595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 11/10/2023] [Accepted: 11/13/2023] [Indexed: 12/07/2023]
Abstract
ConspectusThe early years of gold catalysis were dominated by Au(I) complexes and inorganic Au(III) salts. Thanks to the development of chelating ligands, more sophisticated Au(III) complexes can now be easily prepared and handled. The choice of the ancillary ligand has great consequences for the synthesis, properties, and reactivity of the Au(III) complex in question. Among the major factors controlling reactivity are the "trans effect" and the "trans influence" that a ligand imparts at the ligand trans to itself. The kinetic trans effect manifests itself with an increased labilization of the ligand trans to a given ligand and arises from an interplay between ground-state and transition-state effects. The term trans influence, on the other hand, is a ground-state effect only, describing the tendency of a given ligand to weaken the metal-ligand bond trans to itself. Herein, we will use the term "trans effect" to describe both the kinetic and the thermodynamic properties, whereas the term "trans influence" will refer only to thermodynamic properties. We will describe how these trans effects strongly impact the chemistry of the commonly encountered cyclometalated (N,C) Au(III) complexes, a class of complexes we have studied for more than a decade. We found that the outcome of reactions like alkylation, arylation, and alkynylation as well as halide metathesis are dictated by the different trans influence of the two termini of the chelating tpy ligand in (tpy)Au(OAcF)2 (tpy = 2-(p-tolyl)pyridine, OAcF = OCOCF3, tpy-C > tpy-N). There is a strong preference for high trans influence ligands to end up trans to tpy-N, whereas the lower trans influence ligands end up trans to tpy-C. Taking advantage of these preferences, tailor-made (N,C)Au(III) complexes could be prepared. For the functionalization of alkenes at (tpy)Au(OAcF)2, the higher trans effect of tpy-C would suggest that the coordination site trans to tpy-C would be kinetically more available than the one trans to tpy-N. However, due to the thermodynamic preference of having the σ-bonded ligand, resulting from the nucleophilic addition to alkenes, trans to tpy-N, functionalization of alkenes was only observed trans to tpy-N. However, for a catalytic process, the reaction should happen trans to tpy-C, as was observed for the trifluoroacetoxylation of acetylene. When functionalizing acetylene in the coordination site trans to tpy-N, protolytic cleavage of the Au-C(vinyl) bond to release the product did not occur at all, whereas trans to tpy-C protolytic cleavage of the Au-C(vinyl) bond occurred readily, in agreement with the higher trans influence of tpy-C over tpy-N. The large impact of the trans effects in Au(III) complexes is finally exemplified with the synthesis of [(tpy)Au(π-allyl)]+[NTf2]-, which resulted in a highly asymmetric π + σ bonding of the allyl moiety. Here, the bonding is such that the most thermodynamically favorable situation is achieved, with the carbon trans to tpy-N bonded in a σ-fashion and the π-allyl double bond being coordinated trans to tpy-C.
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Affiliation(s)
- Marte Sofie Martinsen Holmsen
- Department
of Chemistry, University of Oslo, P.O. Box 1033, Blindern, N-0315 Oslo, Norway
- Centre
for Materials Science and Nanotechnology, University of Oslo, P.O. Box 1126, Blindern, N-0316 Oslo, Norway
| | - Ainara Nova
- Department
of Chemistry, University of Oslo, P.O. Box 1033, Blindern, N-0315 Oslo, Norway
- Centre
for Materials Science and Nanotechnology, University of Oslo, P.O. Box 1126, Blindern, N-0316 Oslo, Norway
- Hylleraas
Centre for Quantum Molecular Sciences, Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, N-0315 Oslo, Norway
- UiT-The
Arctic University of Norway, N-9037 Tromsø, Norway
| | - Mats Tilset
- Department
of Chemistry, University of Oslo, P.O. Box 1033, Blindern, N-0315 Oslo, Norway
- Centre
for Materials Science and Nanotechnology, University of Oslo, P.O. Box 1126, Blindern, N-0316 Oslo, Norway
- Hylleraas
Centre for Quantum Molecular Sciences, Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, N-0315 Oslo, Norway
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9
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Gukathasan S, Obisesan OA, Saryazdi S, Ratliff L, Parkin S, Grossman RB, Awuah SG. A Conformationally Restricted Gold(III) Complex Elicits Antiproliferative Activity in Cancer Cells. Inorg Chem 2023; 62:13118-13129. [PMID: 37530672 PMCID: PMC11268950 DOI: 10.1021/acs.inorgchem.3c02066] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/03/2023]
Abstract
Diamine ligands are effective structural scaffolds for tuning the reactivity of transition-metal complexes for catalytic, materials, and phosphorescent applications and have been leveraged for biological use. In this work, we report the synthesis and characterization of a novel class of cyclometalated [C^N] Au(III) complexes bearing secondary diamines including a norbornane backbone, (2R,3S)-N2,N3-dibenzylbicyclo[2.2.1]heptane-2,3-diamine, or a cyclohexane backbone, (1R,2R)-N1,N2-dibenzylcyclohexane-1,2-diamine. X-ray crystallography confirms the square-planar geometry and chirality at nitrogen. The electronic character of the conformationally restricted norbornane backbone influences the electrochemical behavior with redox potentials of -0.8 to -1.1 V, atypical for Au(III) complexes. These compounds demonstrate promising anticancer activity, particularly, complex 1, which bears a benzylpyridine organogold framework, and supported by the bicyclic conformationally restricted diaminonorbornane, shows good potency in A2780 cells. We further show that a cellular response to 1 evokes reactive oxygen species (ROS) production and does not induce mitochondrial dysfunction. This class of complexes provides significant stability and reactivity for different applications in protein modification, catalysis, and therapeutics.
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Affiliation(s)
| | | | - Setareh Saryazdi
- Department of Chemistry, University of Kentucky, Lexington KY 40506, USA
| | - Libby Ratliff
- Department of Chemistry, University of Kentucky, Lexington KY 40506, USA
| | - Sean Parkin
- Department of Chemistry, University of Kentucky, Lexington KY 40506, USA
| | - Robert B. Grossman
- Department of Chemistry, University of Kentucky, Lexington KY 40506, USA
| | - Samuel G. Awuah
- Department of Chemistry, University of Kentucky, Lexington KY 40506, USA
- Center for Pharmaceutical Research and Innovation and Department of Pharmaceutical Sciences, College of Pharmacy University of Kentucky, Lexington KY 40536, USA
- Markey Cancer Center, University of Kentucky, Lexington KY 40536
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10
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Scott SC, Cadge JA, Boden GK, Bower JF, Russell CA. A Hemilabile NHC-Gold Complex and its Application to the Redox Neutral 1,2-Oxyarylation of Feedstock Alkenes. Angew Chem Int Ed Engl 2023; 62:e202301526. [PMID: 36995930 PMCID: PMC10962591 DOI: 10.1002/anie.202301526] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/21/2023] [Accepted: 03/30/2023] [Indexed: 03/31/2023]
Abstract
We describe a AuI complex of a hemi-labile (C^N) N-heterocyclic carbene ligand that is able to mediate oxidative addition of aryl iodides. Detailed computational and experimental investigations have been undertaken to verify and rationalize the oxidative addition process. Application of this initiation mode has resulted in the first examples of "exogenous oxidant-free" AuI /AuIII catalyzed 1,2-oxyarylations of ethylene and propylene. These demanding yet powerful processes establish these commodity chemicals as nucleophilic-electrophilic building blocks in catalytic reaction design.
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Affiliation(s)
- Samuel C. Scott
- School of ChemistryUniversity of BristolCantock's CloseBristolBS8 1TSUK
| | - Jamie A. Cadge
- School of ChemistryUniversity of BristolCantock's CloseBristolBS8 1TSUK
| | - Grace K. Boden
- School of ChemistryUniversity of BristolCantock's CloseBristolBS8 1TSUK
| | - John F. Bower
- Department of ChemistryUniversity of LiverpoolCrown StreetLiverpoolL69 7ZDUK
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11
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Gao P, Xu J, Zhou T, Liu Y, Bisz E, Dziuk B, Lalancette R, Szostak R, Zhang D, Szostak M. L-Shaped Heterobidentate Imidazo[1,5-a]pyridin-3-ylidene (N,C)-Ligands for Oxidant-Free Au I /Au III Catalysis. Angew Chem Int Ed Engl 2023; 62:e202218427. [PMID: 36696514 PMCID: PMC9992098 DOI: 10.1002/anie.202218427] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/18/2023] [Accepted: 01/25/2023] [Indexed: 01/26/2023]
Abstract
In the last decade, major advances have been made in homogeneous gold catalysis. However, AuI /AuIII catalytic cycle remains much less explored due to the reluctance of AuI to undergo oxidative addition and the stability of the AuIII intermediate. Herein, we report activation of aryl halides at gold(I) enabled by NHC (NHC=N-heterocyclic carbene) ligands through the development of a new class of L-shaped heterobidentate ImPy (ImPy=imidazo[1,5-a]pyridin-3-ylidene) N,C ligands that feature hemilabile character of the amino group in combination with strong σ-donation of the carbene center in a rigid conformation, imposed by the ligand architecture. Detailed characterization and control studies reveal key ligand features for AuI /AuIII redox cycle, wherein the hemilabile nitrogen is placed at the coordinating position of a rigid framework. Given the tremendous significance of homogeneous gold catalysis, we anticipate that this ligand platform will find widespread application.
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Affiliation(s)
- Pengcheng Gao
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102 (United States)
| | - Jihong Xu
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, Institute of Theoretical Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)
| | - Tongliang Zhou
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102 (United States)
| | - Yanhong Liu
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, Institute of Theoretical Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)
| | - Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052 (Poland)
| | - Błażej Dziuk
- Department of Chemistry, University of Science and Technology, Norwida 4/6, Wroclaw 50-373 (Poland)
| | - Roger Lalancette
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102 (United States)
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383 (Poland)
| | - Dongju Zhang
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, Institute of Theoretical Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102 (United States)
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12
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Novel NHC-Based Au(I) Complexes as Precursors of Highly Pure Au(0) Nuggets under Oxidative Conditions. Molecules 2023; 28:molecules28052302. [PMID: 36903548 PMCID: PMC10005697 DOI: 10.3390/molecules28052302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 02/14/2023] [Accepted: 02/24/2023] [Indexed: 03/06/2023] Open
Abstract
The Lewis-acidic character and robustness of NHC-Au(I) complexes enable them to catalyze a large number of reactions, and they are enthroned as the catalysts of choice for many transformations among polyunsaturated substrates. More recently, Au(I)/Au(III) catalysis has been explored either by utilizing external oxidants or by seeking oxidative addition processes with catalysts featuring pendant coordinating groups. Herein, we describe the synthesis and characterization of N-heterocyclic carbene (NHC)-based Au(I) complexes, with and without pendant coordinating groups, and their reactivity in the presence of different oxidants. We demonstrate that when using iodosylbenzene-type oxidants, the NHC ligand undergoes oxidation to afford the corresponding NHC=O azolone products concomitantly with quantitative gold recovery in the form of Au(0) nuggets ~0.5 mm in size. The latter were characterized by SEM and EDX-SEM showing purities above 90%. This study shows that NHC-Au complexes can follow decomposition pathways under certain experimental conditions, thus challenging the believed robustness of the NHC-Au bond and providing a novel methodology to produce Au(0) nuggets.
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13
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Shiri F, Ariafard A. Mechanistic details for oxidative addition of PhICl 2 to gold( i) complexes. Chem Commun (Camb) 2023; 59:4668-4671. [PMID: 36994794 DOI: 10.1039/d3cc00543g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
Our study discovered a new stepwise mechanism for the oxidative addition of PhICl2 to LAuAr. Fewer electron-withdrawing substituents on the Ar ligand increase the energy of Au(i) dx2−y2 orbital, making the reaction easier to achieve.
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Affiliation(s)
- Farshad Shiri
- Department of Chemistry, Islamic Azad University, Central Tehran Branch, Poonak, Tehran, Iran
| | - Alireza Ariafard
- Department of Chemistry, Islamic Azad University, Central Tehran Branch, Poonak, Tehran, Iran
- School of Natural Science (Chemistry), University of Tasmania, Private Bag 75, Hobart, TAS 7001, Australia
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14
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Szalóki G, Babinot J, Martin-Diaconescu V, Mallet-Ladeira S, García-Rodeja Y, Miqueu K, Bourissou D. Ligand-enabled oxidation of gold(i) complexes with o-quinones. Chem Sci 2022; 13:10499-10505. [PMID: 36277619 PMCID: PMC9473537 DOI: 10.1039/d2sc03724f] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 08/03/2022] [Indexed: 11/30/2022] Open
Abstract
Chelating P^P and hemilabile P^N ligands were found to trigger the oxidation of Au(i) complexes by o-benzoquinones. The ensuing Au(iii) catecholate complexes have been characterized by NMR spectroscopy, single crystal X-ray diffraction and X-ray absorption spectroscopy. They adopt tetracoordinate square-planar structures. Reactivity studies substantiate the reversibility of the transformation. In particular, the addition of competing ligands such as chloride and alkenes gives back Au(i) complexes with concomitant release of the o-quinone. DFT calculations provide insight about the structure and relative stability of the Au(i) o-quinone and Au(iii) catecholate forms, and shed light on the 2-electron transfer from gold to the o-quinone.
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Affiliation(s)
- György Szalóki
- Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA, UMR 5069), CNRS, Université Toulouse III - Paul Sabatier 118 Route de Narbonne Toulouse 31062 Cedex 09 France
| | - Julien Babinot
- Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA, UMR 5069), CNRS, Université Toulouse III - Paul Sabatier 118 Route de Narbonne Toulouse 31062 Cedex 09 France
| | - Vlad Martin-Diaconescu
- ALBA Synchrotron - CELLS Carrer de la Llum 2-26 Cerdanyola del Vallès 08290 Barcelona Spain
| | - Sonia Mallet-Ladeira
- Institut de Chimie de Toulouse (UAR 2599) 118 Route de Narbonne Toulouse 31062 Cedex 09 France
| | - Yago García-Rodeja
- Institut des Sciences Analytiques et Physico-Chimie pour l'Environnement et les Matériaux (IPREM, UMR 5254), CNRS, Université de Pau et des Pays de l'Adour E2S UPPA, Hélioparc 2 Avenue du Président Angot Pau 64053 Cedex 09 France
| | - Karinne Miqueu
- Institut des Sciences Analytiques et Physico-Chimie pour l'Environnement et les Matériaux (IPREM, UMR 5254), CNRS, Université de Pau et des Pays de l'Adour E2S UPPA, Hélioparc 2 Avenue du Président Angot Pau 64053 Cedex 09 France
| | - Didier Bourissou
- Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA, UMR 5069), CNRS, Université Toulouse III - Paul Sabatier 118 Route de Narbonne Toulouse 31062 Cedex 09 France
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15
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Park G, Karimi M, Liu W, Gabbaï FP. Green‐Light‐Driven Reductive Elimination of Chlorine from a Carbene‐Xanthylium Gold(III) Complex. Angew Chem Int Ed Engl 2022; 61:e202206265. [DOI: 10.1002/anie.202206265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Indexed: 11/07/2022]
Affiliation(s)
- Gyeongjin Park
- Department of Chemistry Texas A&M University College Station TX 77843 USA
| | | | - Wei‐Chun Liu
- Department of Chemistry Texas A&M University College Station TX 77843 USA
| | - François P. Gabbaï
- Department of Chemistry Texas A&M University College Station TX 77843 USA
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16
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Park G, Karimi M, Liu WC, Gabbai FP. Green‐Light‐Driven Reductive Elimination of Chlorine from a Carbene‐Xanthylium Gold(III) Complex. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202206265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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17
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Font P, Valdés H, Guisado-Barrios G, Ribas X. Hemilabile MIC^N ligands allow oxidant-free Au(I)/Au(III) arylation-lactonization of γ-alkenoic acids. Chem Sci 2022; 13:9351-9360. [PMID: 36093006 PMCID: PMC9384699 DOI: 10.1039/d2sc01966c] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 07/08/2022] [Indexed: 11/27/2022] Open
Abstract
Oxidant-free Au-catalyzed reactions are emerging as a new synthetic tool for innovative organic transformations. Oxidant-free Au-catalyzed reactions are emerging as a new synthetic tool for innovative organic transformations. Still, a deeper mechanistic understanding is needed for a rational design of these processes. Here we describe the synthesis of two Au(i) complexes bearing bidentated hemilabile MIC^N ligands, [AuI(MIC^N)Cl], and their ability to stabilize square-planar Au(iii) species (MIC = mesoionic carbene). The presence of the hemilabile N-ligand contributed to stabilize the ensuing Au(iii) species acting as a five-membered ring chelate upon its coordination to the metal center. The Au(iii) complexes can be obtained either by using external oxidants or, alternatively, by means of feasible oxidative addition with strained biphenylene Csp2–Csp2 bonds as well as with aryl iodides. Based on the fundamental knowledge gained on the redox properties on these Au(i)/Au(iii) systems, we successfully develop a novel Au(i)-catalytic procedure for the synthesis of γ-substituted γ-butyrolactones through the arylation-lactonization reaction of the corresponding γ-alkenoic acid. The oxidative addition of the aryl iodide, which in turn is allowed by the hemilabile nature of the MIC^N ligand, is an essential step for this transformation. A novel hemilabile MIC^N ligand-based Au(i)-catalytic procedure for the synthesis of γ-substituted γ-butyrolactones through the arylation-lactonization reaction of the corresponding γ-alkenoic acid is presented.![]()
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Affiliation(s)
- Pau Font
- Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona, Campus de Montilivi Girona E-17003 Catalonia Spain
| | - Hugo Valdés
- Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona, Campus de Montilivi Girona E-17003 Catalonia Spain
| | - Gregorio Guisado-Barrios
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Universidad de Zaragoza-CSIC Zaragoza 50009 Spain
| | - Xavi Ribas
- Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona, Campus de Montilivi Girona E-17003 Catalonia Spain
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18
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Daley RA, Morrenzin AS, Neufeldt SR, Topczewski JJ. Mechanistic Investigation into the Gold-Catalyzed Decarboxylative Cross-Coupling of Iodoarenes. ACS Catal 2021. [DOI: 10.1021/acscatal.1c01631] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Ryan A. Daley
- Department of Chemistry, University of Minnesota Twin Cities, Minneapolis, Minnesota 55455, United States
| | - Aaron S. Morrenzin
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, United States
| | - Sharon R. Neufeldt
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, United States
| | - Joseph J. Topczewski
- Department of Chemistry, University of Minnesota Twin Cities, Minneapolis, Minnesota 55455, United States
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