1
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Steen JS, de Vries F, Hjelm J, Otten E. Bipolar Verdazyl Radicals for Symmetrical Batteries: Properties and Stability in All States of Charge. Chemphyschem 2023; 24:e202200779. [PMID: 36317641 DOI: 10.1002/cphc.202200779] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Indexed: 11/27/2022]
Abstract
Redox flow batteries based on organic electrolytes are promising energy storage devices, but stable long-term cycling is often difficult to achieve. Bipolar organic charge-storage materials allow the construction of symmetrical flow batteries (i. e., with identical electrolyte composition on both sides), which is a strategy to mitigate crossover-induced degradation. One such class of bipolar compounds are verdazyl radicals, but little is known on their stability/reactivity either as the neutral radical, or in the charged states. Here, we study the chemical properties of a Kuhn-type verdazyl radical (1) and the oxidized/reduced form (1+/- ). Chemical synthesis of the three redox-states provides spectroscopic characterization data, which are used as reference for evaluating the composition of the electrolyte solutions of an H-cell battery during/after cycling. Our data suggest that, rather than the charged states, the decomposition of the parent verdazyl radical is responsible for capacity fade. Kinetic experiments and DFT calculations provide insight in the decomposition mechanism, which is shown to occur by bimolecular disproportionation to form two closed-shell products (leuco-verdazyl 1H and triazole derivative 2).
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Affiliation(s)
- Jelte S Steen
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands
| | - Folkert de Vries
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands
| | - Johan Hjelm
- Department of Energy Conversion and Storage (DTU Energy), Technical University of Denmark, Fysikvej, Building 310, 2800, Kgs Lyngby, Denmark
| | - Edwin Otten
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands
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2
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de Vries F, Otten E. Reversible On/Off Switching of Lactide Cyclopolymerization with a Redox-Active Formazanate Ligand. ACS Catal 2022; 12:4125-4130. [PMID: 35391903 PMCID: PMC8981207 DOI: 10.1021/acscatal.1c05689] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 02/18/2022] [Indexed: 12/17/2022]
Abstract
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Redox-switching of
a formazanate zinc catalyst in ring-opening
polymerization (ROP) of lactide is described. Using a redox-active
ligand bound to an inert metal ion (Zn2+) allows modulation
of the catalytic activity by reversible reduction/oxidation chemistry
at a purely organic fragment. A combination of kinetic and spectroscopic
studies, together with mass spectrometry of the catalysis mixture,
provides insight in the nature of the active species and the initiation
of lactide ring-opening polymerization. The mechanistic data highlight
the key role of the redox-active ligand and provide a rationale for
the formation of cyclic polymer.
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Affiliation(s)
- Folkert de Vries
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG Groningen, The Netherlands
| | - Edwin Otten
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG Groningen, The Netherlands
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3
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van Vliet S, Alachouzos G, de Vries F, Pfeifer L, Feringa BL. Visible light activated BINOL-derived chiroptical switches based on boron integrated hydrazone complexes. Chem Sci 2022; 13:9713-9718. [PMID: 36091916 PMCID: PMC9400604 DOI: 10.1039/d2sc03518a] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 07/30/2022] [Indexed: 11/21/2022] Open
Abstract
Chiral optical switches, which use light to control chirality in a reversible manner, offer unique properties and fascinating prospects in the areas of molecular switching and responsive systems, new photochromic materials and molecular data processing and storage. Herein, we report visible light responsive chiroptical switches based on tetrahedral boron coordination towards an easily accessible hydrazone ligand and optically pure BINOL. Upon instalment of a non-planar dibenzo[a,d]-cycloheptene moiety in the hydrazone ligand's lower half, the enantiopure boron complex shows major chiroptical changes in the CD read-out after visible light irradiation. The thermal isomerization barrier in these chiroptical switching systems showed to be easily adjustable by the introduction of substituents onto the olefinic bond of the cycloheptene ring, giving profound control over their thermal stability. The control over their thermal stability in combination with excellent reversibility, photochemical properties and overall robustness of the complexes makes these BINOL-derived chiroptical switches attractive candidates for usage in advanced applications, e.g. photonic materials and nanotechnology. Chiroptical switches, which use light to control chirality in a reversible manner, offer unique properties and fascinating prospects in the areas of molecular responsive systems, new photochromic materials and molecular data processing and storage.![]()
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Affiliation(s)
- Sven van Vliet
- Stratingh Institute for Chemistry, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, Groningen 9747 AG, Netherlands
| | - Georgios Alachouzos
- Stratingh Institute for Chemistry, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, Groningen 9747 AG, Netherlands
| | - Folkert de Vries
- Stratingh Institute for Chemistry, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, Groningen 9747 AG, Netherlands
| | - Lukas Pfeifer
- EPFL, CH G1 614 (Bâtiment CH), Station 6, Lausanne, CH-1015, Switzerland
| | - Ben L. Feringa
- Stratingh Institute for Chemistry, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, Groningen 9747 AG, Netherlands
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4
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Pérez JM, Postolache R, Castiñeira Reis M, Sinnema EG, Vargová D, de Vries F, Otten E, Ge L, Harutyunyan SR. Manganese(I)-Catalyzed H-P Bond Activation via Metal-Ligand Cooperation. J Am Chem Soc 2021; 143:20071-20076. [PMID: 34797634 PMCID: PMC8662621 DOI: 10.1021/jacs.1c10756] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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Here we report that
chiral Mn(I) complexes are capable of H–P
bond activation. This activation mode enables a general method for
the hydrophosphination of internal and terminal α,β-unsaturated
nitriles. Metal−ligand cooperation, a strategy previously not
considered for catalytic H–P bond activation, is at the base
of the mechanistic action of the Mn(I)-based catalyst. Our computational
studies support a stepwise mechanism for the hydrophosphination and
provide insight into the origin of the enantioselectivity.
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Affiliation(s)
- Juana M Pérez
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Roxana Postolache
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Marta Castiñeira Reis
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Esther G Sinnema
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Denisa Vargová
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Folkert de Vries
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Edwin Otten
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Luo Ge
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Syuzanna R Harutyunyan
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
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5
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Dašková V, Buter J, Schoonen AK, Lutz M, de Vries F, Feringa BL. Chiral Amplification of Phosphoramidates of Amines and Amino Acids in Water. Angew Chem Int Ed Engl 2021; 60:11120-11126. [PMID: 33605523 PMCID: PMC8252365 DOI: 10.1002/anie.202014955] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 02/04/2021] [Indexed: 01/22/2023]
Abstract
The origin of biomolecular homochirality continues to be one of the most fascinating aspects of prebiotic chemistry. Various amplification strategies for chiral compounds to enhance a small chiral preference have been reported, but none of these involves phosphorylation, one of nature's essential chemical reactions. Here we present a simple and robust concept of phosphorylation-based chiral amplification of amines and amino acids in water. By exploiting the difference in solubility of a racemic phosphoramidate and its enantiopure form, we achieved enantioenrichment in solution. Starting with near racemic, phenylethylamine-based phosphoramidates, ee's of up to 95 % are reached in a single amplification step. Particularly noteworthy is the enantioenrichment of phosphorylated amino acids and their derivatives, which might point to a potential role of phosphorus en-route to prebiotic homochirality.
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Affiliation(s)
- Vanda Dašková
- Stratingh Institute for ChemistryUniversity of GroningenNijenborgh 49747AGGroningenThe Netherlands
| | - Jeffrey Buter
- Stratingh Institute for ChemistryUniversity of GroningenNijenborgh 49747AGGroningenThe Netherlands
| | - Anne K. Schoonen
- Stratingh Institute for ChemistryUniversity of GroningenNijenborgh 49747AGGroningenThe Netherlands
| | - Martin Lutz
- Crystal and Structural ChemistryBijvoet Centre for Biomolecular ResearchUtrecht UniversityPadualaan 83584CHUtrechtThe Netherlands
| | - Folkert de Vries
- Stratingh Institute for ChemistryUniversity of GroningenNijenborgh 49747AGGroningenThe Netherlands
| | - Ben L. Feringa
- Stratingh Institute for ChemistryUniversity of GroningenNijenborgh 49747AGGroningenThe Netherlands
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6
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Wolzak LA, Hermans JJ, de Vries F, van den Berg KJ, Reek JNH, Tromp M, Korstanje TJ. Mechanistic elucidation of monoalkyltin(iv)-catalyzed esterification. Catal Sci Technol 2021; 11:3326-3332. [PMID: 34123363 PMCID: PMC8147323 DOI: 10.1039/d1cy00184a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 02/17/2021] [Indexed: 01/12/2023]
Abstract
Monoalkyltin(iv) complexes are well-known catalysts for esterification reactions and polyester formation, yet the mode of operation of these Lewis acidic complexes is still unknown. Here, we report on mechanistic studies of n-butylstannoic acid in stoichiometric and catalytic reactions, analyzed by NMR, IR and MS techniques. While the chemistry of n-butyltin(iv) carboxylates is dominated by formation of multinuclear tin assemblies, we found that under catalytically relevant conditions only monomeric n-BuSn(OAc)3 and dimeric (n-BuSnOAc2OEt)2 are present. Density functional theory (DFT) calculations provide support for a mononuclear mechanism, where n-BuSn(OAc)3 and dimeric (n-BuSnOAc2OEt)2 are regarded as off-cycle species, and suggest that carbon-oxygen bond breaking is the rate-determining step.
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Affiliation(s)
- Lukas A Wolzak
- Sustainable Materials Characterization, van 't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands
- Bio-inspired, Homogeneous and Supramolecular Catalysis, van 't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands
| | - Joen J Hermans
- Molecular Photonics, van 't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands
| | - Folkert de Vries
- Faculty of Science and Engineering, Materials Chemistry - Zernike Institute for Advanced Materials, University of Groningen Nijenborgh 4 9747 AG Groningen The Netherlands
| | | | - Joost N H Reek
- Bio-inspired, Homogeneous and Supramolecular Catalysis, van 't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands
| | - Moniek Tromp
- Sustainable Materials Characterization, van 't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands
- Faculty of Science and Engineering, Materials Chemistry - Zernike Institute for Advanced Materials, University of Groningen Nijenborgh 4 9747 AG Groningen The Netherlands
| | - Ties J Korstanje
- Sustainable Materials Characterization, van 't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands
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7
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Milocco F, de Vries F, Siebe HS, Engbers S, Demeshko S, Meyer F, Otten E. Widening the Window of Spin-Crossover Temperatures in Bis(formazanate)iron(II) Complexes via Steric and Noncovalent Interactions. Inorg Chem 2021; 60:2045-2055. [PMID: 33464882 PMCID: PMC7856632 DOI: 10.1021/acs.inorgchem.0c03593] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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Bis(formazanate)iron(II) complexes
undergo a thermally induced S = 0 to S = 2 spin transition in solution.
Here we present a study of how steric effects and π-stacking
interactions between the triarylformazanate ligands affect the
spin-crossover behavior, in addition to electronic substituent effects.
Moreover, the effect of increasing the denticity of the formazanate
ligands is explored by including additional OMe donors in the ligand
(7). In total, six new compounds (2–7) have been synthesized and characterized, both in solution
and in the solid state, via spectroscopic, magnetic, and structural
analyses. The series spans a broad range of spin-crossover temperatures
(T1/2) for the LS ⇌ HS equilibrium
in solution, with the exception of compound 6 which remains
high-spin (S = 2) down to 210 K. In the solid state, 6 was shown to exist in two distinct forms: a tetrahedral
high-spin complex (6a, S = 2) and a
rare square-planar structure with an intermediate-spin state (6b, S = 1). SQUID measurements, 57Fe Mössbauer spectroscopy, and differential scanning calorimetry
indicate that in the solid state the square-planar form 6b undergoes an incomplete spin-change-coupled isomerization to tetrahedral 6a. The complex that contains additional OMe donors (7) results in a six-coordinate (NNO)2Fe coordination
geometry, which shifts the spin-crossover to significantly higher
temperatures (T1/2 = 444 K). The available
experimental and computational data for 7 suggest that
the Fe···OMe interaction is retained upon spin-crossover.
Despite the difference in coordination environment, the weak OMe donors
do not significantly alter the electronic structure or ligand-field
splitting, and the occurrence of spin-crossover (similar to the compounds
lacking the OMe groups) originates from a large degree of metal–ligand
π-covalency. A series of
Fe(II) complexes with formazanate ligands are
reported, and ligand substituent effects on structure and spin-crossover
properties are examined. These ligand modifications allow isolation
of compounds with tetrahedral geometries in both low- and high-spin
ground states as well as an intermediate-spin square-planar complex.
Steric properties, π-stacking interactions, and additional donor
substituents lead to a wide range of spin-crossover temperatures (T1/2) in this class of compounds.
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Affiliation(s)
- Francesca Milocco
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Folkert de Vries
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Harmke S Siebe
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Silène Engbers
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Serhiy Demeshko
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstraße 4, 37077 Göttingen, Germany
| | - Franc Meyer
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstraße 4, 37077 Göttingen, Germany
| | - Edwin Otten
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
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8
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Affiliation(s)
- Folkert de Vries
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Raquel Travieso-Puente
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Peter Roewen
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Edwin Otten
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
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9
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Milocco F, de Vries F, Bartels IMA, Havenith RWA, Cirera J, Demeshko S, Meyer F, Otten E. Electronic Control of Spin-Crossover Properties in Four-Coordinate Bis(formazanate) Iron(II) Complexes. J Am Chem Soc 2020; 142:20170-20181. [PMID: 33197175 PMCID: PMC7705964 DOI: 10.1021/jacs.0c10010] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
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The
transition between spin states in d-block metal complexes has
important ramifications for their structure and reactivity, with applications
ranging from information storage materials to understanding catalytic
activity of metalloenzymes. Tuning the ligand field (ΔO) by steric and/or electronic effects has provided spin-crossover
compounds for several transition metals in the periodic table, but
this has mostly been limited to coordinatively saturated metal centers
in octahedral ligand environments. Spin-crossover complexes with low
coordination numbers are much rarer. Here we report a series of four-coordinate,
(pseudo)tetrahedral Fe(II) complexes with formazanate ligands and
demonstrate how electronic substituent effects can be used to modulate
the thermally induced transition between S = 0 and S = 2 spin states in solution. All six compounds undergo
spin-crossover in solution with T1/2 above
room temperature (300–368 K). While structural analysis by
X-ray crystallography shows that the majority of these compounds are
low-spin in the solid state (and remain unchanged upon heating), we
find that packing effects can override this preference and give rise
to either rigorously high-spin (6) or gradual spin-crossover
behavior (5) also in the solid state. Density functional
theory calculations are used to delineate the empirical trends in
solution spin-crossover thermodynamics. In all cases, the stabilization
of the low-spin state is due to the π-acceptor properties of
the formazanate ligand, resulting in an “inverted” ligand
field, with an approximate “two-over-three” splitting
of the d-orbitals and a high degree of metal–ligand covalency
due to metal → ligand π-backdonation. The computational
data indicate that the electronic nature of the para-substituent has a different influence depending on whether it is
present at the C–Ar or N–Ar rings, which is ascribed
to the opposing effect on metal–ligand σ- and π-bonding.
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Affiliation(s)
- Francesca Milocco
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Folkert de Vries
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Imke M A Bartels
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Remco W A Havenith
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.,Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.,Ghent Quantum Chemistry Group, Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281 (S3), B-9000 Gent, Belgium
| | - Jordi Cirera
- Departament de Química Inorgànica i Orgànica and Institut de Recerca de Química Teòrica i Computacional, Universitat de Barcelona, Diagonal 645, 08028 Barcelona, Spain
| | - Serhiy Demeshko
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstraße 4, 37077 Göttingen, Germany
| | - Franc Meyer
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstraße 4, 37077 Göttingen, Germany
| | - Edwin Otten
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
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10
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Taschinski S, Döpp R, Ackermann M, Rominger F, de Vries F, Menger MFSJ, Rudolph M, Hashmi ASK, Klein JEMN. Light-Induced Mechanistic Divergence in Gold(I) Catalysis: Revisiting the Reactivity of Diazonium Salts. Angew Chem Int Ed Engl 2019; 58:16988-16993. [PMID: 31552696 PMCID: PMC6899485 DOI: 10.1002/anie.201908268] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 09/02/2019] [Indexed: 01/02/2023]
Abstract
In a systematic study of the Au-catalyzed reaction of o-alkynylphenols with aryldiazonium salts, we find that essentially the same reaction conditions lead to a change in mechanism when a light source is applied. If the reaction is carried out at room temperature using a AuI catalyst, the diazonium salt undergoes electrophilic deauration of a vinyl AuI intermediate and provides access to substituted azobenzofurans. If the reaction mixture is irradiated with blue LED light, C-C bond formation due to N2 -extrusion from the diazonium salt is realized selectively, using the same starting materials without the need for an additional photo(redox) catalyst under aerobic conditions. We report a series of experiments demonstrating that the same vinyl AuI intermediate is capable of producing the observed products under photolytic and thermal conditions. The finding that a vinyl AuI complex can directly, without the need for an additional photo(redox) catalyst, result in C-C bond formation under photolytic conditions is contrary to the proposed mechanistic pathways suggested in the literature till date and highlights that the role of oxidation state changes in photoredox catalysis involving Au is thus far only poorly understood and may hold surprises for the future. Computational results indicate that photochemical activation can occur directly from a donor-acceptor complex formed between the vinyl AuI intermediate and the diazonium salt.
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Affiliation(s)
- Svenja Taschinski
- Molecular Inorganic ChemistryStratingh Institute for ChemistryFaculty of Science and EngineeringUniversity of GroningenNijenborgh 49747AGGroningenThe Netherlands
- Organisch-Chemisches InstitutHeidelberg UniversityIm Neuenheimer Feld 27069120HeidelbergGermany
| | - René Döpp
- Organisch-Chemisches InstitutHeidelberg UniversityIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Martin Ackermann
- Organisch-Chemisches InstitutHeidelberg UniversityIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Frank Rominger
- Organisch-Chemisches InstitutHeidelberg UniversityIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Folkert de Vries
- Molecular Inorganic ChemistryStratingh Institute for ChemistryFaculty of Science and EngineeringUniversity of GroningenNijenborgh 49747AGGroningenThe Netherlands
| | - Maximilian F. S. J. Menger
- Zernike Institute for Advanced MaterialsFaculty of Science and EngineeringUniversity of GroningenNijenborgh 49747AGGroningenThe Netherlands
| | - Matthias Rudolph
- Organisch-Chemisches InstitutHeidelberg UniversityIm Neuenheimer Feld 27069120HeidelbergGermany
| | - A. Stephen K. Hashmi
- Organisch-Chemisches InstitutHeidelberg UniversityIm Neuenheimer Feld 27069120HeidelbergGermany
- Chemistry DepartmentFaculty of ScienceKing Abdulaziz UniversityJeddah21589Saudi Arabia
| | - Johannes E. M. N. Klein
- Molecular Inorganic ChemistryStratingh Institute for ChemistryFaculty of Science and EngineeringUniversity of GroningenNijenborgh 49747AGGroningenThe Netherlands
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11
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Milocco F, de Vries F, Dall'Anese A, Rosar V, Zangrando E, Otten E, Milani B. Palladium alkyl complexes with a formazanate ligand: synthesis, structure and reactivity. Dalton Trans 2018; 47:14445-14451. [DOI: 10.1039/c8dt03130d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The synthesis of formazanate palladium complexes is reported. Ligand-based redox-reactions and insertions of unsaturated substrates into the Pd–CH3 bond are studied.
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Affiliation(s)
- Francesca Milocco
- Dipartimento di Scienze Chimiche e Farmaceutiche
- Università di Trieste
- 34127 Trieste
- Italy
- Stratingh Institute for Chemistry
| | - Folkert de Vries
- Dipartimento di Scienze Chimiche e Farmaceutiche
- Università di Trieste
- 34127 Trieste
- Italy
- Stratingh Institute for Chemistry
| | - Anna Dall'Anese
- Dipartimento di Scienze Chimiche e Farmaceutiche
- Università di Trieste
- 34127 Trieste
- Italy
| | - Vera Rosar
- Dipartimento di Scienze Chimiche e Farmaceutiche
- Università di Trieste
- 34127 Trieste
- Italy
| | - Ennio Zangrando
- Dipartimento di Scienze Chimiche e Farmaceutiche
- Università di Trieste
- 34127 Trieste
- Italy
| | - Edwin Otten
- Stratingh Institute for Chemistry
- University of Groningen
- 9747 AG Groningen
- The Netherlands
| | - Barbara Milani
- Dipartimento di Scienze Chimiche e Farmaceutiche
- Università di Trieste
- 34127 Trieste
- Italy
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