1
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Mandel MJ, Krieck S, Görls H, Westerhausen M. Bulky Hybrid
C‐
Scorpionate/Amidinate Complexes of Lithium and Zinc. Eur J Inorg Chem 2022. [DOI: 10.1002/ejic.202200249] [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]
Affiliation(s)
- Miles J. Mandel
- Institute of Inorganic and Analytical Chemistry Chair of Inorganic Chemistry I Friedrich Schiller University Jena Humboldtstraße 8 07743 Jena Germany
| | - Sven Krieck
- Institute of Inorganic and Analytical Chemistry Chair of Inorganic Chemistry I Friedrich Schiller University Jena Humboldtstraße 8 07743 Jena Germany
| | - Helmar Görls
- Institute of Inorganic and Analytical Chemistry Chair of Inorganic Chemistry I Friedrich Schiller University Jena Humboldtstraße 8 07743 Jena Germany
| | - Matthias Westerhausen
- Institute of Inorganic and Analytical Chemistry Chair of Inorganic Chemistry I Friedrich Schiller University Jena Humboldtstraße 8 07743 Jena Germany
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2
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Bagnarelli L, Dolmella A, Santini C, Vallesi R, Giacomantonio R, Gabrielli S, Pellei M. A New Dimeric Copper(II) Complex of Hexyl Bis(pyrazolyl)acetate Ligand as an Efficient Catalyst for Allylic Oxidations. Molecules 2021; 26:molecules26206271. [PMID: 34684852 PMCID: PMC8541649 DOI: 10.3390/molecules26206271] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 10/13/2021] [Accepted: 10/14/2021] [Indexed: 11/21/2022] Open
Abstract
A new dimeric copper(II) bromide complex, [Cu(LOHex)Br(μ-Br)]2 (1), was prepared by a reaction of CuBr2 with the hexyl bis(pyrazol-1-yl)acetate ligand (LOHex) in acetonitrile solution and fully characterized in the solid state and in solution. The crystal structure of 1 was also determined: the complex is interlinked by two bridging bromide ligands and possesses terminal bromide ligands on each copper atom. The two pyrazolyl ligands in 1 coordinate with the nitrogen atoms to complete the Cu coordination sphere, resulting in a five-coordinated geometry—away from idealized trigonal bipyramidal and square pyramidal geometries—which can better be described as distorted square pyramidal, as measured by the τ and χ structural parameters. The pendant hexyloxy chain is disordered over two arrangements, with final site occupancies refined to 0.705 and 0.295. The newly synthesized complex was evaluated as a catalyst in copper-catalyzed C–H oxidation for allylic functionalization through a Kharasch–Sosnovsky reaction without any external reducing agent. Using 0.5 mol% of this catalyst, and tert-butyl peroxybenzoate (Luperox) as an oxidant, allylic benzoates were obtained with up to 90% yield. The general reaction time was only slightly decreased to 24 h but a very significant decrease in the alkene:Luperox ratio to 3:1 was achieved. These factors show relevant improvements with respect to classical Kharasch–Sosnovsky reactions in terms of rate and amount of reagents. The present study highlights the potential of copper(II) complexes containing functionalized bis(pyrazol-1-yl)acetate ligands as efficient catalysts for allylic oxidations.
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Affiliation(s)
- Luca Bagnarelli
- Chemistry Division, School of Science and Technology, University of Camerino, Via S. Agostino 1, 62032 Camerino, Italy; (L.B.); (C.S.); (R.V.); (R.G.)
| | - Alessandro Dolmella
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Via Marzolo 5, 35131 Padova, Italy;
| | - Carlo Santini
- Chemistry Division, School of Science and Technology, University of Camerino, Via S. Agostino 1, 62032 Camerino, Italy; (L.B.); (C.S.); (R.V.); (R.G.)
| | - Riccardo Vallesi
- Chemistry Division, School of Science and Technology, University of Camerino, Via S. Agostino 1, 62032 Camerino, Italy; (L.B.); (C.S.); (R.V.); (R.G.)
| | - Roberto Giacomantonio
- Chemistry Division, School of Science and Technology, University of Camerino, Via S. Agostino 1, 62032 Camerino, Italy; (L.B.); (C.S.); (R.V.); (R.G.)
| | - Serena Gabrielli
- Chemistry Division, School of Science and Technology, University of Camerino, Via S. Agostino 1, 62032 Camerino, Italy; (L.B.); (C.S.); (R.V.); (R.G.)
- Correspondence: (S.G.); (M.P.); Tel.: +39-0737-402219 (S.G.); +39-0737-402213 (M.P.)
| | - Maura Pellei
- Chemistry Division, School of Science and Technology, University of Camerino, Via S. Agostino 1, 62032 Camerino, Italy; (L.B.); (C.S.); (R.V.); (R.G.)
- Correspondence: (S.G.); (M.P.); Tel.: +39-0737-402219 (S.G.); +39-0737-402213 (M.P.)
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3
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Keisers K, Hüppe HM, Iffland-Mühlhaus L, Hoffmann A, Göbel C, Apfel UP, Weber B, Herres-Pawlis S. Interplay of Spin Crossover and Coordination-Induced Spin State Switch for Iron Bis(pyrazolyl)methanes in Solution. Inorg Chem 2020; 59:15343-15354. [PMID: 33002361 DOI: 10.1021/acs.inorgchem.0c02306] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Bis(pyrazolyl)bipyridinylmethane iron(II) complexes show a versatile spin state switching behavior in different solvents. In the solid, the magnetic properties of the compounds have been characterized by X-ray diffraction, Mößbauer spectroscopy, and SQUID magnetometry and point toward a high spin state. For nitrilic solvents, the solvation of the complexes leads to a change of the coordination environment from {N5O} to {N6} and results in a temperature-dependent SCO behavior. Thermodynamic properties of this transformation are obtained via UV/vis spectroscopy, SQUID measurements, and the Evans NMR method. Moreover, a coordination-induced spin state switch (CISSS) to low spin is observed by using methanol as solvent, triggered through a rearrangement of the coordination sphere. The same behavior can be observed by changing the stoichiometry of the ligand-to-metal ratio in MeCN, where the process is reversible. This transformation is monitored via UV/vis spectroscopy, and the resulting new bis-meridional coordination motif, first described for bis(pyrazolyl)methanes, is characterized in the solid state via X-ray diffraction, Mößbauer spectroscopy, and SQUID measurements. The sophisticated correlation of these switchable properties in dependence on different types of solvents reveals that the influence of the solvent on the coordination environment and magnetic properties should not be underestimated. Furthermore, careful investigation is necessary to differentiate between a thermally-induced spin crossover and a coordination-induced spin state switch.
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Affiliation(s)
- Kristina Keisers
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1a, 52074 Aachen, Germany
| | - Henrika M Hüppe
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1a, 52074 Aachen, Germany
| | - Linda Iffland-Mühlhaus
- Inorganic Chemistry I, Ruhr-Universität Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Alexander Hoffmann
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1a, 52074 Aachen, Germany
| | - Christoph Göbel
- Department of Chemistry, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - Ulf-Peter Apfel
- Inorganic Chemistry I, Ruhr-Universität Bochum, Universitätsstraße 150, 44801 Bochum, Germany.,Fraunhofer UMSICHT, Osterfelder Straße 3, 46047 Oberhausen, Germany
| | - Birgit Weber
- Department of Chemistry, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - Sonja Herres-Pawlis
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1a, 52074 Aachen, Germany
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4
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Liebhäuser P, Keisers K, Hoffmann A, Schnappinger T, Sommer I, Thoma A, Wilfer C, Schoch R, Stührenberg K, Bauer M, Dürr M, Ivanović-Burmazović I, Herres-Pawlis S. Record Broken: A Copper Peroxide Complex with Enhanced Stability and Faster Hydroxylation Catalysis. Chemistry 2017; 23:12171-12183. [PMID: 28425134 DOI: 10.1002/chem.201700887] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Indexed: 11/08/2022]
Abstract
Tyrosinase model systems pinpoint pathways to translating Nature's synthetic abilities for useful synthetic catalysts. Mostly, they use N-donor ligands which mimic the histidine residues coordinating the two copper centres. Copper complexes with bis(pyrazolyl)methanes with pyridinyl or imidazolyl moieties are already reported as excellent tyrosinase models. Substitution of the pyridinyl donor results in the new ligand HC(3-tBuPz)2 (4-CO2 MePy) which stabilises a room-temperature stable μ-η2 :η2 -peroxide dicopper(II) species upon oxygenation. It reveals highly efficient catalytic activity as it hydroxylates 8-hydroxyquinoline in high yields (TONs of up to 20) and much faster than all other model systems (max. conversion within 7.5 min). Stoichiometric reactions with para-substituted sodium phenolates show saturation kinetics which are nearly linear for electron-rich substrates. The resulting Hammett correlation proves the electrophilic aromatic substitution mechanism. Furthermore, density functional theory (DFT) calculations elucidate the influence of the substituent at the pyridinyl donor: the carboxymethyl group adjusts the basicity and nucleophilicity without additional steric demand. This substitution opens up new pathways in reactivity tuning.
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Affiliation(s)
- Patricia Liebhäuser
- Institut für Anorganische Chemie, Rheinisch-Westfälische Technische Hochschule Aachen, Landoltweg 1, 52074, Aachen, Germany
| | - Kristina Keisers
- Institut für Anorganische Chemie, Rheinisch-Westfälische Technische Hochschule Aachen, Landoltweg 1, 52074, Aachen, Germany
| | - Alexander Hoffmann
- Institut für Anorganische Chemie, Rheinisch-Westfälische Technische Hochschule Aachen, Landoltweg 1, 52074, Aachen, Germany
| | - Thomas Schnappinger
- Department für Chemie und Pharmazie, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377, München, Germany
| | - Isabella Sommer
- Institut für Anorganische Chemie, Rheinisch-Westfälische Technische Hochschule Aachen, Landoltweg 1, 52074, Aachen, Germany
| | - Anne Thoma
- Institut für Anorganische Chemie, Rheinisch-Westfälische Technische Hochschule Aachen, Landoltweg 1, 52074, Aachen, Germany
| | - Claudia Wilfer
- Institut für Anorganische Chemie, Rheinisch-Westfälische Technische Hochschule Aachen, Landoltweg 1, 52074, Aachen, Germany
| | - Roland Schoch
- Department Chemie, Universität Paderborn, Warburger Straße 100, 33098, Paderborn, Germany
| | - Kai Stührenberg
- Department Chemie, Universität Paderborn, Warburger Straße 100, 33098, Paderborn, Germany
| | - Matthias Bauer
- Department Chemie, Universität Paderborn, Warburger Straße 100, 33098, Paderborn, Germany
| | - Maximilian Dürr
- Department Chemie und Pharmazie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 1, 91058, Erlangen, Germany
| | - Ivana Ivanović-Burmazović
- Department Chemie und Pharmazie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 1, 91058, Erlangen, Germany
| | - Sonja Herres-Pawlis
- Institut für Anorganische Chemie, Rheinisch-Westfälische Technische Hochschule Aachen, Landoltweg 1, 52074, Aachen, Germany
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5
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Herber U, Hegner K, Wolters D, Siris R, Wrobel K, Hoffmann A, Lochenie C, Weber B, Kuckling D, Herres-Pawlis S. Iron(II) and Zinc(II) Complexes with Tetradentate Bis(pyrazolyl)methane Ligands as Catalysts for the Ring-Opening Polymerisation ofrac-Lactide. Eur J Inorg Chem 2017. [DOI: 10.1002/ejic.201601345] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Ulrich Herber
- Institute of Inorganic Chemistry; RWTH Aachen University; Landoltweg 1 52074 Aachen Germany
| | - Katharina Hegner
- Institute of Inorganic Chemistry; RWTH Aachen University; Landoltweg 1 52074 Aachen Germany
| | - Daniel Wolters
- Institute of Inorganic Chemistry; RWTH Aachen University; Landoltweg 1 52074 Aachen Germany
| | - Rita Siris
- Department of Chemistry and Pharmacy; LMU Munich; Butenandtstr. 5-13 81377 München Germany
| | - Karina Wrobel
- Institute of Inorganic Chemistry; RWTH Aachen University; Landoltweg 1 52074 Aachen Germany
| | - Alexander Hoffmann
- Institute of Inorganic Chemistry; RWTH Aachen University; Landoltweg 1 52074 Aachen Germany
| | - Charles Lochenie
- Inorganic Chemistry II; University of Bayreuth; Universitätsstraße 30 95440 Bayreuth Germany
| | - Birgit Weber
- Inorganic Chemistry II; University of Bayreuth; Universitätsstraße 30 95440 Bayreuth Germany
| | - Dirk Kuckling
- Department of Chemistry; Paderborn University; Warburger Str. 100 33098 Paderborn Germany
| | - Sonja Herres-Pawlis
- Institute of Inorganic Chemistry; RWTH Aachen University; Landoltweg 1 52074 Aachen Germany
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6
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Manzano BR, Jalón FA, Carrión MC, Durá G. Bis(pyrazol-1-yl)(pyridin-x-yl)methane Ligands - Mono- or Ditopic Ligands in Complexes and Supramolecular Frameworks. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201501271] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Blanca R. Manzano
- Departamento de Química Inorgánica, Orgánica y Bioquímica; Facultad de Ciencias y Tecnologías Químicas-IRICA; Universidad de Castilla-La Mancha; Avda. C. J. Cela, 10 13071 Ciudad Real Spain
| | - Félix A. Jalón
- Departamento de Química Inorgánica, Orgánica y Bioquímica; Facultad de Ciencias y Tecnologías Químicas-IRICA; Universidad de Castilla-La Mancha; Avda. C. J. Cela, 10 13071 Ciudad Real Spain
| | - M. Carmen Carrión
- Departamento de Química Inorgánica, Orgánica y Bioquímica; Facultad de Ciencias y Tecnologías Químicas-IRICA; Universidad de Castilla-La Mancha; Avda. C. J. Cela, 10 13071 Ciudad Real Spain
- Facultad de Ciencias y Tecnologías Químicas-IRICA; Fundación Parque Científico y Tecnológico de Castilla-La Mancha (Fundación PCTCLM); Bulevar Río Alberche s/n 45007 Toledo Spain
| | - Gema Durá
- Departamento de Química Inorgánica, Orgánica y Bioquímica; Facultad de Ciencias y Tecnologías Químicas-IRICA; Universidad de Castilla-La Mancha; Avda. C. J. Cela, 10 13071 Ciudad Real Spain
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7
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Hoffmann A, Herres-Pawlis S. Donor-driven conformational flexibility in a real-life catalytic dicopper(ii) peroxo complex. Phys Chem Chem Phys 2016; 18:6430-40. [DOI: 10.1039/c5cp05009j] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The conformers of the real-life tyrosinase model [Cu2O2{HC(3-tBuPz)2(Py)}2]2+which displays catalytic hydroxylation reactivity were investigated by density functional theory (DFT) studies including second-order perturbation theory and charge decomposition analysis (CDA).
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Affiliation(s)
- A. Hoffmann
- Lehrstuhl für Bioanorganische Chemie
- Institut für Anorganische Chemie
- RWTH Aachen University
- 52074 Aachen
- Germany
| | - S. Herres-Pawlis
- Lehrstuhl für Bioanorganische Chemie
- Institut für Anorganische Chemie
- RWTH Aachen University
- 52074 Aachen
- Germany
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8
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Wilfer C, Liebhäuser P, Hoffmann A, Erdmann H, Grossmann O, Runtsch L, Paffenholz E, Schepper R, Dick R, Bauer M, Dürr M, Ivanović-Burmazović I, Herres-Pawlis S. Efficient Biomimetic Hydroxylation Catalysis with a Bis(pyrazolyl)imidazolylmethane Copper Peroxide Complex. Chemistry 2015; 21:17639-49. [PMID: 26458073 DOI: 10.1002/chem.201501685] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Indexed: 11/08/2022]
Abstract
Bis(pyrazolyl)methane ligands are excellent components of model complexes used to investigate the activity of the enzyme tyrosinase. Combining the N donors 3-tert-butylpyrazole and 1-methylimidazole results in a ligand that is capable of stabilising a (μ-η(2) :η(2) )-dicopper(II) core that resembles the active centre of tyrosinase. UV/Vis spectroscopy shows blueshifted UV bands in comparison to other known peroxo complexes, due to donor competition from different ligand substituents. This effect was investigated with the help of theoretical calculations, including DFT and natural transition orbital analysis. The peroxo complex acts as a catalyst capable of hydroxylating a variety of phenols by using oxygen. Catalytic conversion with the non-biological phenolic substrate 8-hydroxyquinoline resulted in remarkable turnover numbers. In stoichiometric reactions, substrate-binding kinetics was observed and the intrinsic hydroxylation constant, kox , was determined for five phenolates. It was found to be the fastest hydroxylation model system determined so far, reaching almost biological activity. Furthermore, Hammett analysis proved the electrophilic character of the reaction. This sheds light on the subtle role of donor strength and its influence on hydroxylation activity.
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Affiliation(s)
- Claudia Wilfer
- Department für Chemie und Pharmazie, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 München (Germany).,Institut für Anorganische Chemie, Rheinisch-Westfälische Technische Hochschule Aachen, Landoltweg 1, 52074 Aachen (Germany)
| | - Patricia Liebhäuser
- Institut für Anorganische Chemie, Rheinisch-Westfälische Technische Hochschule Aachen, Landoltweg 1, 52074 Aachen (Germany)
| | - Alexander Hoffmann
- Institut für Anorganische Chemie, Rheinisch-Westfälische Technische Hochschule Aachen, Landoltweg 1, 52074 Aachen (Germany)
| | - Hannes Erdmann
- Department für Chemie und Pharmazie, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 München (Germany)
| | - Oleg Grossmann
- Department für Chemie und Pharmazie, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 München (Germany)
| | - Leander Runtsch
- Department für Chemie und Pharmazie, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 München (Germany)
| | - Eva Paffenholz
- Institut für Anorganische Chemie, Rheinisch-Westfälische Technische Hochschule Aachen, Landoltweg 1, 52074 Aachen (Germany)
| | - Rahel Schepper
- Department Chemie, Universität Paderborn, Warburger Straße 100, 33098 Paderborn (Germany)
| | - Regina Dick
- Department Chemie, Universität Paderborn, Warburger Straße 100, 33098 Paderborn (Germany)
| | - Matthias Bauer
- Department Chemie, Universität Paderborn, Warburger Straße 100, 33098 Paderborn (Germany)
| | - Maximilian Dürr
- Department Chemie und Pharmazie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 1, 91058 Erlangen (Germany)
| | - Ivana Ivanović-Burmazović
- Department Chemie und Pharmazie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 1, 91058 Erlangen (Germany)
| | - Sonja Herres-Pawlis
- Department für Chemie und Pharmazie, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 München (Germany). .,Institut für Anorganische Chemie, Rheinisch-Westfälische Technische Hochschule Aachen, Landoltweg 1, 52074 Aachen (Germany).
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Citek C, Herres-Pawlis S, Stack TDP. Low temperature syntheses and reactivity of Cu2O2 active-site models. Acc Chem Res 2015; 48:2424-33. [PMID: 26230113 DOI: 10.1021/acs.accounts.5b00220] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Nature's facility with dioxygen outmatches modern chemistry in the oxidation and oxygenation of materials and substrates for biosynthesis and cellular metabolism. The Earth's most abundant naturally occurring oxidant is-frankly-poorly understood and controlled, and thus underused. Copper-based enzyme metallocofactors are ubiquitous to the efficient consumption of dioxygen by all domains of life. Over the last several decades, we have joined many research groups in the study of copper- and dioxygen-dependent enzymes through close investigation of synthetically derived, small-molecule active-site analogs. Simple copper-dioxygen clusters bearing structural and spectroscopic similarity to dioxygen-activating enzymes can be probed for their fundamental geometrical, electronic, and reactive properties using the tools available to inorganic and synthetic chemistry. Our exploration of the copper-dioxygen arena has sustained product evaluation of the key dynamics and reactivity of binuclear Cu2O2 compounds. Almost exclusively operating at low temperatures, from -78 °C to solution characterization even at -125 °C, we have identified numerous compounds supported by simple and easily accessed, low molecular weight ligands-chiefly families of bidentate diamine chelates. We have found that by stripping away complexity in comparison to extended protein tertiary structures or sophisticated, multinucleating architectures, we can experimentally manipulate activated compounds and open pathways of reactivity toward exogenous substrates that both inform on and extend fundamental mechanisms of oxygenase enzymes. Our recent successes have advanced understanding of the tyrosinase enzyme, and related hemocyanin and NspF, and the copper membrane monooxygenases, specifically particulate methane monooxygenase (pMMO) and ammonia monooxygenase (AMO). Tyrosinase, ubiquitously distributed throughout life, is fundamental to the copper-based oxidation of phenols and the production of chromophores by dedicated biosynthesis or incidental oxidative browning. The copper membrane monooxygenases are comparatively new entrants to the copper-dioxygen field. While pMMO mediates the synthetically tantalizing transformation of methane to methanol, AMO catalyzes the first metabolic step in deriving chemical energy from ammonia-a reaction massively represented on a global scale and a critical component of chemical homeostasis on Earth. In this Account, we begin by introduction of the synthetic copper-dioxygen chemistry field, from techniques to the differential coordination of dioxygen with copper. Then, we describe the unambiguous self-assembly of an oxygenated tyrosinase mimic from basic constituents (copper, dioxygen, and monodentate-imidazole histidine analogs) and the resulting emergence of intrinsic reactivity, free of any influence due to the protein environment. Next, we discuss the first catalytic oxidation of phenol through a fully characterized tyrosinase mimic, derived from molecular oxygen, and its application to substrates unreactive in the native enzyme system. Finally, we detail evidence for chemical plausibility of dioxygen activation in pMMO (and AMO) through a high-valent species and the thermodynamic criteria that beg introduction of the Cu(III) state to biological redox catalysis.
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Affiliation(s)
- Cooper Citek
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Sonja Herres-Pawlis
- Institute of Inorganic Chemistry, RWTH Aachen University, Aachen 52074, Germany
| | - T. Daniel P. Stack
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
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10
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Wilfer C, Liebhäuser P, Erdmann H, Hoffmann A, Herres-Pawlis S. Biomimetic Hydroxylation Catalysis Through Self-Assembly of a Bis(pyrazolyl)methane Copper-Peroxo Complex. Eur J Inorg Chem 2014. [DOI: 10.1002/ejic.201402957] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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11
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Hoffmann A, Flörke U, Herres-Pawlis S. Insights into Different Donor Abilities in Bis(pyrazolyl)pyridinylmethane Transition Metal Complexes. Eur J Inorg Chem 2014. [DOI: 10.1002/ejic.201400056] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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