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Schulz J, Antala J, Rezazgui D, Císařová I, Štěpnička P. Synthesis, Structure, Reactivity, and Intramolecular Donor-Acceptor Interactions in a Phosphinoferrocene Stibine and Its Corresponding Phosphine Chalcogenides and Stiboranes. Inorg Chem 2023; 62:14028-14043. [PMID: 37566394 PMCID: PMC10466383 DOI: 10.1021/acs.inorgchem.3c02075] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Indexed: 08/12/2023]
Abstract
Ferrocene-based phosphines equipped with additional functional groups are versatile ligands for coordination chemistry and catalysis. This contribution describes a new compound of this type, combining phosphine and stibine groups at the ferrocene backbone, viz. 1-(diphenylphosphino)-1'-(diphenylstibino)ferrocene (1). Phosphinostibine 1 and the corresponding P-chalcogenide derivatives Ph2P(E)fcSbPh2 (1E, fc = ferrocene-1,1'-diyl, E = O, S, Se) were synthesized and further converted to the corresponding stiboranes Ph2P(E)fcSb(O2C6Cl4)Ph2 (6 and 6E) by oxidation with o-chloranil. All compounds were characterized by spectroscopic methods, X-ray diffraction analysis, cyclic voltammetry, and theoretical methods. Both NMR spectroscopy and DFT calculations confirmed the presence of P → Sb and P═O → Sb donor-acceptor interactions in 6 and 6O, triggered by the oxidation of the stibine moiety into Lewis acidic stiborane. The corresponding interactions in 6S and 6Se were of the same type but significantly weaker. A coordination study with AuCl as the model metal fragment revealed that the phosphine group acts as the "primary" coordination site, in line with its higher basicity. The obtained Au(I) complexes were applied as catalysts in the Au-catalyzed cyclization of N-propargylbenzamide and in the oxidative [2 + 2 + 1] cyclization of ethynylbenzene with acetonitrile and pyridine N-oxides. The catalytic results showed that the stibine complexes had worse catalytic performance than their phosphine counterparts, most likely due to the formation of weaker coordination bonds and hence poorer stabilization of the active metal species. Nevertheless, the stibine moiety could be used to fine-tune the properties of the ligated metal center by changing the oxidation state or substituents at the "remote" Sb atom.
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Affiliation(s)
- Jiří Schulz
- Department
of Inorganic Chemistry,
Faculty of Science, Charles University, Hlavova 2030, 128 40 Prague, Czech Republic
| | - Jakub Antala
- Department
of Inorganic Chemistry,
Faculty of Science, Charles University, Hlavova 2030, 128 40 Prague, Czech Republic
| | - David Rezazgui
- Department
of Inorganic Chemistry,
Faculty of Science, Charles University, Hlavova 2030, 128 40 Prague, Czech Republic
| | - Ivana Císařová
- Department
of Inorganic Chemistry,
Faculty of Science, Charles University, Hlavova 2030, 128 40 Prague, Czech Republic
| | - Petr Štěpnička
- Department
of Inorganic Chemistry,
Faculty of Science, Charles University, Hlavova 2030, 128 40 Prague, Czech Republic
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2
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Electrochemical functionalization at anodic conditions of multi-walled carbon nanotubes with chlorodiphenylphosphine. J Colloid Interface Sci 2022; 623:915-926. [DOI: 10.1016/j.jcis.2022.05.125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 05/10/2022] [Accepted: 05/19/2022] [Indexed: 11/19/2022]
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3
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Hu H, Ichiryu H, Nakajima K, Ogasawara M. Estimating Effective Steric and Electronic Impacts of a Ferrocenyl Group in Organophosphines. ACS OMEGA 2021; 6:5981-5989. [PMID: 33681636 PMCID: PMC7931422 DOI: 10.1021/acsomega.1c00307] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 02/05/2021] [Indexed: 06/12/2023]
Abstract
A series of monodentate ferrocenylphosphines, Fc3P (1a), Fc2PhP (1b), and Fc2ArP (1c; Fc = ferrocenyl, Ar = 3,4-methylenedioxyphenyl), were prepared, and their electronic and steric properties were quantitatively determined. By the IR measurements of their respective Ni(CO)3(phosphine) complexes, the electronic properties of the ferrocenyl group in organophosphines were estimated to be similar to those of primary alkyl groups. The ferrocenyl group is a better electron donor than a methyl group and a poorer donor than an ethyl group. The gold(I) chloride complexes of 1a-c were prepared and their X-ray crystal structures were determined. The %V bur parameters for 1a-c were calculated using the X-ray structural data, and their ″Tolman cone angles″ were estimated. The steric influence of the ferrocenyl group in organophosphines was clarified to be larger than those of cyclohexyl, tert-butyl, and o-tolyl groups and is comparable to that of a mesityl group.
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Affiliation(s)
- Hao Hu
- Department
of Natural Science, Graduate School of Science and Technology, Tokushima
International Science Institute, and Research Cluster on ″Innovative
Chemical Sensing″, Tokushima University, Tokushima 770-8506, Japan
- Graduate
School of Life Science, Hokkaido University, Kita-ku, Sapporo 001-0021, Japan
| | - Hiroki Ichiryu
- Department
of Natural Science, Graduate School of Science and Technology, Tokushima
International Science Institute, and Research Cluster on ″Innovative
Chemical Sensing″, Tokushima University, Tokushima 770-8506, Japan
| | - Kiyohiko Nakajima
- Department
of Chemistry, Aichi University of Education, Igaya, Kariya, Aichi 448-8542, Japan
| | - Masamichi Ogasawara
- Department
of Natural Science, Graduate School of Science and Technology, Tokushima
International Science Institute, and Research Cluster on ″Innovative
Chemical Sensing″, Tokushima University, Tokushima 770-8506, Japan
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4
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Straube A, Coburger P, Michak M, Ringenberg MR, Hey-Hawkins E. The core of the matter - arene substitution determines the coordination and catalytic behaviour of tris(1-phosphanyl-1'-ferrocenylene)arene gold(I) complexes. Dalton Trans 2020; 49:16667-16682. [PMID: 33084677 DOI: 10.1039/d0dt02743j] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Changing the aromatic core of C3-symmetric tris(ferrocenyl)arene-based tris-phosphanes has profound effects on their coordination behaviour towards gold(i). Depending on the arene (s-triazine, benzene, or trifluorobenzene), four different coordination modes can be distinguished and their preference has been rationalised using computational methods. The corresponding 1 : 1 ligand-to-metal complexes, studied by variable-temperature NMR spectroscopy, revealed fluctional behaviour in solution. Given the presence of up to three or six ferrocenylene spacers per complex, their electrochemistry was investigated. The redox-responsive nature of the complexes can be advantageously exploited in the catalytic ring-closing isomerisation of N-(2-propyn-1-yl)benzamide, where the benzene-based 2 : 3 ligand-to-metal complex has been shown to display multiple activity states depending on the degree of (reversible) oxidation in a preliminary trial.
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Affiliation(s)
- Axel Straube
- Institute of Inorganic Chemistry, Universität Leipzig, Johannisallee 29, D-04103 Leipzig, Germany.
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5
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Straube A, Coburger P, Dütsch L, Hey-Hawkins E. Triple the fun: tris(ferrocenyl)arene-based gold(i) complexes for redox-switchable catalysis. Chem Sci 2020; 11:10657-10668. [PMID: 34094320 PMCID: PMC8162263 DOI: 10.1039/d0sc03604h] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The modular syntheses of C3-symmetric tris(ferrocenyl)arene-based tris-phosphanes and their homotrinuclear gold(i) complexes are reported. Choosing the arene core allows fine-tuning of the exact oxidation potentials and thus tailoring of the electrochemical response. The tris[chloridogold(i)] complexes were investigated in the catalytic ring-closing isomerisation of N-(2-propyn-1-yl)benzamide, showing cooperative behaviour vs. a mononuclear chloridogold(i) complex. Adding one, two, or three equivalents of 1,1′-diacetylferrocenium[tetrakis(perfluoro-tert-butoxy)aluminate] as an oxidant during the catalytic reaction (in situ) resulted in a distinct, stepwise influence on the resulting catalytic rates. Isolation of the oxidised species is possible, and using them as (pre-)catalysts (ex situ oxidation) confirmed the activity trend. Proving the intactness of the P–Au–Cl motif during oxidation, the tri-oxidised benzene-based complex has been structurally characterised. Trinuclear gold(i) complexes of C3-symmetric tris(ferrocenyl)arene-based tris-phosphanes with four accessible oxidation states catalyse the ring-closing isomerisation of N-(2-propyn-1-yl)benzamide with different rates depending on their redox state.![]()
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Affiliation(s)
- Axel Straube
- Institute of Inorganic Chemistry, Universität Leipzig Johannisallee 29 D-04103 Leipzig Germany https://anorganik.chemie.unileipzig.de/de/anorganik/ak-hey-hawkins/
| | - Peter Coburger
- Institute of Inorganic Chemistry, Universität Leipzig Johannisallee 29 D-04103 Leipzig Germany https://anorganik.chemie.unileipzig.de/de/anorganik/ak-hey-hawkins/
| | - Luis Dütsch
- Institute of Inorganic Chemistry, Universität Regensburg Universitätsstr. 31 D-93053 Regensburg Germany
| | - Evamarie Hey-Hawkins
- Institute of Inorganic Chemistry, Universität Leipzig Johannisallee 29 D-04103 Leipzig Germany https://anorganik.chemie.unileipzig.de/de/anorganik/ak-hey-hawkins/
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6
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Grecchi S, Arnaboldi S, Korb M, Cirilli R, Araneo S, Guglielmi V, Tomboni G, Magni M, Benincori T, Lang H, Mussini PR. Widening the Scope of “Inherently Chiral” Electrodes: Enantiodiscrimination of Chiral Electroactive Probes with Planar Stereogenicity. ChemElectroChem 2020. [DOI: 10.1002/celc.202000657] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Sara Grecchi
- Dipartimento di ChimicaUniversità degli Studi di Milano Via Golgi 19 20133 Milan Italy
| | - Serena Arnaboldi
- Dipartimento di ChimicaUniversità degli Studi di Milano Via Golgi 19 20133 Milan Italy
| | - Marcus Korb
- The University of Western AustraliaFaculty of Sciences, School of Molecular Sciences 35 Stirling Highway, Crawley Perth Western Australia 6009 Australia
| | - Roberto Cirilli
- Centro Nazionale per il Controllo e la Valutazione dei FarmaciIstituto Superiore di Sanità Viale Regina Elena 299 00161 Roma Italy
| | - Silvia Araneo
- Dipartimento di ChimicaUniversità degli Studi di Milano Via Golgi 19 20133 Milan Italy
| | - Vittoria Guglielmi
- Dipartimento di ChimicaUniversità degli Studi di Milano Via Golgi 19 20133 Milan Italy
| | - Giorgio Tomboni
- Dipartimento di ChimicaUniversità degli Studi di Milano Via Golgi 19 20133 Milan Italy
| | - Mirko Magni
- Dipartimento di ChimicaUniversità degli Studi di Milano Via Golgi 19 20133 Milan Italy
| | - Tiziana Benincori
- Dipartimento di Scienza e Alta TecnologiaUniversità degli Studi dell'Insubria Via Valleggio 11 22100 Como Italy
| | - Heinrich Lang
- Technische Universität ChemnitzFaculty of Natural SciencesInstitute of Chemistry, Inorganic Chemistry Straße der Nationen 62 D-09107 Chemnitz Germany
| | - Patrizia R. Mussini
- Dipartimento di ChimicaUniversità degli Studi di Milano Via Golgi 19 20133 Milan Italy
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7
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Korb M, Schaarschmidt D, Grumbt M, König M, Lang H. Evaluation of the Transferability of the “Flexible Steric Bulk” Concept from N‐Heterocyclic Carbenes to Planar‐Chiral Phosphinoferrocenes and their Electronic Modification. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000414] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Marcus Korb
- Technische Universität Chemnitz Faculty of Natural Sciences Institute of Chemistry Inorganic Chemistry 09107 Chemnitz Germany
| | - Dieter Schaarschmidt
- Technische Universität Chemnitz Faculty of Natural Sciences Institute of Chemistry Inorganic Chemistry 09107 Chemnitz Germany
| | - Martin Grumbt
- Technische Universität Chemnitz Faculty of Natural Sciences Institute of Chemistry Inorganic Chemistry 09107 Chemnitz Germany
| | - Matthias König
- Technische Universität Chemnitz Faculty of Natural Sciences Institute of Chemistry Inorganic Chemistry 09107 Chemnitz Germany
| | - Heinrich Lang
- Technische Universität Chemnitz Faculty of Natural Sciences Institute of Chemistry Inorganic Chemistry 09107 Chemnitz Germany
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8
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Swarts PJ, Conradie J. Solvent and substituent effect on electrochemistry of ferrocenylcarboxylic acids. J Electroanal Chem (Lausanne) 2020. [DOI: 10.1016/j.jelechem.2020.114164] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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9
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Straube A, Coburger P, Ringenberg MR, Hey‐Hawkins E. Tricoordinate Coinage Metal Complexes with a Redox-Active Tris-(Ferrocenyl)triazine Backbone Feature Triazine-Metal Interactions. Chemistry 2020; 26:5758-5764. [PMID: 32022973 PMCID: PMC7317378 DOI: 10.1002/chem.202000226] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Indexed: 11/09/2022]
Abstract
2,4,6-Tris(1-diphenylphosphanyl-1'-ferrocenylene)-1,3,5-triazine (1) coordinates all three coinage metal(I) ions in a 1:1 tridentate coordination mode. The C3 -symmetric coordination in both solid state and solution is stabilised by an uncommon cation-π interaction between the triazine core and the metal cation. Intramolecular dynamic behaviour was observed by variable-temperature NMR spectroscopy. The borane adduct of 1, 1BH3 , displays four accessible oxidation states, suggesting complexes of 1 to be intriguing candidates for redox-switchable catalysis. Complexes 1Cu, 1Ag, and 1Au display a more complicated electrochemical behaviour, and the electrochemical mechanism was studied by temperature-resolved UV/Vis spectroelectrochemistry and chemical oxidation.
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Affiliation(s)
- Axel Straube
- Institute of Inorganic ChemistryUniversität LeipzigJohannisallee 2904103LeipzigGermany
| | - Peter Coburger
- Institute of Inorganic ChemistryUniversität LeipzigJohannisallee 2904103LeipzigGermany
- Present address: Institute of Inorganic ChemistryUniversität RegensburgUniversitätsstraße 3193051RegensburgGermany
| | - Mark R. Ringenberg
- Institute of Inorganic ChemistryUniversität StuttgartPfaffenwaldring 5570569StuttgartGermany
| | - Evamarie Hey‐Hawkins
- Institute of Inorganic ChemistryUniversität LeipzigJohannisallee 2904103LeipzigGermany
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10
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Dey S, Buzsáki D, Bruhn C, Kelemen Z, Pietschnig R. Bulky 1,1'-bisphosphanoferrocenes and their coordination behaviour towards Cu(i). Dalton Trans 2020; 49:6668-6681. [PMID: 32342065 DOI: 10.1039/d0dt00941e] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Two bulky mesityl substituted dppf-analogues Fe(C5H4PMes2)2 (Mes = 2,4,6-Me3C6H2, 1) and Fe(C5H4PMes2)(C5H4PPh2) (Mes = 2,4,6-Me3C6H2, Ph = C6H5, 3) have been prepared and their properties as donor ligands have been explored using heteronuclear NMR spectroscopy and in particular via1JP-Se coupling, cyclic voltammetry and DFT calculations. Based on the results obtained, a series of mono- and dinuclear Cu(i) complexes have been prepared with these new diphosphane ligands using Br-, I-, and BF4- as counter anions. For the very bulky ligand 1 rare and unprecedented double bridging complexation modes have been observed containing two non-planar Cu2Br2 units, while for the other dinuclear complexes planar Cu2Br2 units have been found. The Cu(i) complexes of 1 and 3 were then used as catalysts for CO2-fixation reaction with terminal alkynes, and complexes with ligand 3 were found to be more efficient than those with 1. DFT calculations performed on compounds 1, 3 and their Cu(i) complexes were able to verify the trend of these catalytic reactions.
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Affiliation(s)
- Subhayan Dey
- Institut für Chemie und CINSaT, University of Kassel, Heinrich Plett-Straße 40, 34132 Kassel, Germany.
| | - Daniel Buzsáki
- Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, and MTA-BME Computation Driven Chemistry Research Group, Szent Gellért tér 4, 1111 Budapest, Hungary
| | - Clemens Bruhn
- Institut für Chemie und CINSaT, University of Kassel, Heinrich Plett-Straße 40, 34132 Kassel, Germany.
| | - Zsolt Kelemen
- Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, and MTA-BME Computation Driven Chemistry Research Group, Szent Gellért tér 4, 1111 Budapest, Hungary
| | - Rudolf Pietschnig
- Institut für Chemie und CINSaT, University of Kassel, Heinrich Plett-Straße 40, 34132 Kassel, Germany.
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12
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Isenberg S, Weller S, Kargin D, Valić S, Schwederski B, Kelemen Z, Bruhn C, Krekić K, Maurer M, Feil CM, Nieger M, Gudat D, Nyulászi L, Pietschnig R. Bis-[3]Ferrocenophanes with Central >E-E'< Bonds (E, E'=P, SiH): Preparation, Properties, and Thermal Activation. ChemistryOpen 2019; 8:1235-1243. [PMID: 31592068 PMCID: PMC6769432 DOI: 10.1002/open.201900182] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Indexed: 11/17/2022] Open
Abstract
A series of bis-[3]ferrocenophanes of the general type Fe(C5H4E')2E-E(E'C5H4)2Fe (E=P, SiH and E'=PtBu, NneoPentyl, NSi(CH3)3) with an isolobal molecular framework have been prepared and characterized by heteronuclear NMR spectroscopy and X-ray crystallography. The thermal dissociation behavior with respect to homolytic fission of the central bond generating phosphorus centered radicals was investigated using EPR spectroscopy and quantum chemical calculations.
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Affiliation(s)
- Stefan Isenberg
- Institute for Chemistry and CINSaTUniversity of KasselHeinrich Plett-Straße 4034132KasselGermany
| | - Stefan Weller
- Institute for Inorganic ChemistryUniversity of StuttgartPfaffenwaldring 5570550StuttgartGermany
| | - Denis Kargin
- Institute for Chemistry and CINSaTUniversity of KasselHeinrich Plett-Straße 4034132KasselGermany
| | - Srećko Valić
- Ruđer Bošković InstituteBijenička cesta 5410000ZagrebCroatia
| | - Brigitte Schwederski
- Institute for Inorganic ChemistryUniversity of StuttgartPfaffenwaldring 5570550StuttgartGermany
| | - Zsolt Kelemen
- Institute for Chemistry and CINSaTUniversity of KasselHeinrich Plett-Straße 4034132KasselGermany
- Department of Inorganic and Analytical Chemistry and MTA-BME Computation Driven Chemistry Research GroupBudapest University of Technology and EconomicsSzent Gellért tér 41111BudapestHungary
| | - Clemens Bruhn
- Institute for Chemistry and CINSaTUniversity of KasselHeinrich Plett-Straße 4034132KasselGermany
| | - Kristijan Krekić
- Institute for Chemistry and CINSaTUniversity of KasselHeinrich Plett-Straße 4034132KasselGermany
| | - Martin Maurer
- Institute for Chemistry and CINSaTUniversity of KasselHeinrich Plett-Straße 4034132KasselGermany
| | - Christoph M. Feil
- Institute for Inorganic ChemistryUniversity of StuttgartPfaffenwaldring 5570550StuttgartGermany
| | - Martin Nieger
- Department of ChemistryUniversity of HelsinkiP.O Box 55Helsinki00014Finland
| | - Dietrich Gudat
- Institute for Inorganic ChemistryUniversity of StuttgartPfaffenwaldring 5570550StuttgartGermany
| | - László Nyulászi
- Department of Inorganic and Analytical Chemistry and MTA-BME Computation Driven Chemistry Research GroupBudapest University of Technology and EconomicsSzent Gellért tér 41111BudapestHungary
| | - Rudolf Pietschnig
- Institute for Chemistry and CINSaTUniversity of KasselHeinrich Plett-Straße 4034132KasselGermany
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13
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Oßwald S, Casper LA, Anders P, Schiebel E, Demeshko S, Winter RF. Electrochemical, Spectroelectrochemical, Mößbauer, and EPR Spectroscopic Studies on Ferrocenyl-Substituted Tritylium Dyes. Chemistry 2018; 24:12524-12538. [PMID: 29904938 DOI: 10.1002/chem.201802364] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 06/12/2018] [Indexed: 11/09/2022]
Abstract
Four monoferrocenyl tritylium derivatives with donor-substituted (OMe, NMe2 ) aryl rings are reported, along with their spectroscopic and electrochemical properties. All the complexes show a one-electron reduction and a quasi-reversible ferrocene oxidation at a very positive potential. Small quadrupole splittings, ΔEQ , in Mößbauer spectra agree with highly electron-deficient ferrocenes. Comparison of the experimental half-wave potentials for ferrocene oxidation, E1/2 (Fc/Fc+ ), with those estimated from established correlations of E1/2 (Fc/Fc+ ) with ΔEQ indicates that the E1/2 values of the anisyl-substituted congeners FcOMe+ and FcMeOMe+ are affected by Coulombic repulsion between the positive charges at the Fe ion and the neighboring methylium site. Electronic spectra are recorded and interpreted with the aid of quantum chemical calculations. UV/Vis spectroelectrochemical measurements as well as chemical reduction provide insight into the redox-induced color changes upon ferrocene oxidation or upon reduction to the neutral trityl radicals. The neutral radicals reversibly form EPR-silent dimers. This process is studied by temperature-dependent EPR spectroscopy, and thermodynamic data for their dimerization are determined. Experimental and quantum chemical data suggest that the dimers assume classical hexaarylethane structures as opposed to normal or "offset" Jacobson-Nauta-type structures.
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Affiliation(s)
- Steffen Oßwald
- Fachbereich Chemie, Universität Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Larissa A Casper
- Fachbereich Chemie, Universität Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Patrick Anders
- Fachbereich Chemie, Universität Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Eva Schiebel
- Fachbereich Chemie, Universität Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Serhiy Demeshko
- Fakultät für Chemie, Georg-August-Universität Göttingen, Tammannstrasse 4, 37077, Göttingen, Germany
| | - Rainer F Winter
- Fachbereich Chemie, Universität Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
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14
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Buitendach BE, Erasmus E, Niemantsverdriet JW, Swarts JC. Can Electrochemical Measurements Be Used To Predict X-ray Photoelectron Spectroscopic Data? The Case of Ferrocenyl-β-Diketonato Complexes of Manganese(III). Inorg Chem 2018; 57:6606-6616. [PMID: 29762020 DOI: 10.1021/acs.inorgchem.8b00745] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In order to better understand intramolecular communication between molecular fragments, a series of ferrocene-functionalized β-diketonato manganese(III) complexes, [Mn(FcCOCHCOR)3] with R = CF3, 1, CH3, 2, Ph = C6H5, 3, and Fc = FeII(η5-C5H4)(η5-C5H5), 4, the mixed ligand β-diketonato complex [Mn(FcCOCHCOFc)2(FcCOCHCOCH3)], 5, as well as the acac complex [Mn(CH3COCHCOCH3)3], 6, were subjected to an electrochemical and X-ray photoelectron spectroscopy (XPS) study. The ferrocenyl (FeII) and MnIII redox potentials, E°', and photoelectron lines were sufficiently resolved in each complex to demonstrate a linear correlation between E°' and group electronegativities of ligand R groups, χR, or ΣχR, as well as with binding energies of both the Fe 2p3/2 and Mn 2p3/2 photoelectron lines. These relationships are consistent with effective communication between molecular fragments of 1-5. From these relationships, prediction of Mn and Fe core electron binding energies in [Mn(R1COCHCOR2)3] complexes from known manganese and/or ferrocenyl redox potentials are, therefore, now possible. Ligand infrared carbonyl stretching frequencies were successfully related to binding energy as a measure of the energy required for inner-sphere reorganization. In particular it became possible to explain why, upon electrochemical oxidation or photoionization, the ferrocenyl FeII inner-shell of 1-5 needs more energy in complexes with ligands bearing electron-withdrawing (CF3) groups than in ligands bearing electron-donating groups such as ferrocenyl. The XPS determined entity Iratio (the ratio between the intensities of the satellite and main metal 2p3/2 photoelectron lines) is an indication not only of the amount of charge transferred, but also of the degree of inner-sphere reorganization. Just as for binding energy, the quantity Iratio was also found to be related to the energy requirements for the inner-sphere reorganization depicted by the vibrational frequency, vco.
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Affiliation(s)
| | - Elizabeth Erasmus
- Department of Chemistry , University of the Free State , Bloemfontein 9300 , South Africa
| | | | - Jannie C Swarts
- Department of Chemistry , University of the Free State , Bloemfontein 9300 , South Africa
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15
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Lik A, Kargin D, Isenberg S, Kelemen Z, Pietschnig R, Helten H. PBP bridged [3]ferrocenophane: a bisphosphanylborane with a redox trigger. Chem Commun (Camb) 2018; 54:2471-2474. [PMID: 29387839 DOI: 10.1039/c7cc09759j] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Stereospecific access to the unprecedented P-B-P bridged [3]ferrocenophane Fe(C5H4PtBu)2BMes is presented. In contrast to acyclic ferrocenylphosphanes, we find evidence for a shift of spin-density from Fe to P upon pyramidal inversion of the P centers in the mono-cation; the latter has a lifetime of τ = 0.31(4) s.
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Affiliation(s)
- Artur Lik
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen, Germany.
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16
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Verschoor-Kirss MJ, Hendricks O, Verschoor CM, Conry R, Kirss RU. Chemical oxidation of ferrocenyl(phenyl)phosphines and ferrocenyl(phenyl)phosphine chalcogenides. Inorganica Chim Acta 2016. [DOI: 10.1016/j.ica.2016.05.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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17
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Gäbler C, Speck JM, Korb M, Schaarschmidt D, Lang H. (Ferrocenylthienyl)phosphines: Synthesis, electrochemistry and their use in Suzuki-Miyaura C,C coupling. J Organomet Chem 2016. [DOI: 10.1016/j.jorganchem.2016.03.027] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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18
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Lu F, Elschenbroich C, Harms K, Burghaus O, Pietzonka C. Paramagnetic ([5]Trovacenyl)phenylphosphane: Intramolecular Electronic Communication and Construction of Heterobimetallic Palladium and Chromium Complexes. Eur J Inorg Chem 2015. [DOI: 10.1002/ejic.201500095] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Feng Lu
- Fachbereich Chemie, Philipps‐Universität Marburg, 35032 Marburg, Germany, https://www.uni‐marburg.de/fb15
| | - Christoph Elschenbroich
- Fachbereich Chemie, Philipps‐Universität Marburg, 35032 Marburg, Germany, https://www.uni‐marburg.de/fb15
| | - Klaus Harms
- Fachbereich Chemie, Philipps‐Universität Marburg, 35032 Marburg, Germany, https://www.uni‐marburg.de/fb15
| | - Olaf Burghaus
- Fachbereich Chemie, Philipps‐Universität Marburg, 35032 Marburg, Germany, https://www.uni‐marburg.de/fb15
| | - Clemens Pietzonka
- Fachbereich Chemie, Philipps‐Universität Marburg, 35032 Marburg, Germany, https://www.uni‐marburg.de/fb15
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van As A, Joubert CC, Buitendach BE, Erasmus E, Conradie J, Cammidge AN, Chambrier I, Cook MJ, Swarts JC. Tetrabenzoporphyrin and -mono-, -cis-di- and Tetrabenzotriazaporphyrin Derivatives: Electrochemical and Spectroscopic Implications of meso CH Group Replacement with Nitrogen. Inorg Chem 2015; 54:5329-41. [PMID: 25970004 DOI: 10.1021/acs.inorgchem.5b00380] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Adele van As
- Department of Chemistry, University of the Free State, Bloemfontein 9300, South Africa
| | - Chris C. Joubert
- Department of Chemistry, University of the Free State, Bloemfontein 9300, South Africa
| | | | - Elizabeth Erasmus
- Department of Chemistry, University of the Free State, Bloemfontein 9300, South Africa
| | - Jeanet Conradie
- Department of Chemistry, University of the Free State, Bloemfontein 9300, South Africa
| | - Andrew N. Cammidge
- School of Chemistry, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Isabelle Chambrier
- School of Chemistry, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Michael J. Cook
- School of Chemistry, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Jannie C. Swarts
- Department of Chemistry, University of the Free State, Bloemfontein 9300, South Africa
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20
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Tiedemann MA, Mandell CL, Chan BC, Nataro C. X-ray structures and oxidative electrochemistry of phosphine sulfides and phosphine selenides. Inorganica Chim Acta 2014. [DOI: 10.1016/j.ica.2014.06.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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21
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Miesel D, Hildebrandt A, Rüffer T, Schaarschmidt D, Lang H. Electron‐Transfer Studies of
trans
‐Platinum Bis(acetylide) Complexes. Eur J Inorg Chem 2014. [DOI: 10.1002/ejic.201402686] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Dominique Miesel
- Inorganic Chemistry, Institute of Chemistry, Faculty of Natural Sciences, Technische Universität Chemnitz, 09107 Chemnitz, Germany, http://www.tu‐chemnitz.de/chemie/anorg/
| | - Alexander Hildebrandt
- Inorganic Chemistry, Institute of Chemistry, Faculty of Natural Sciences, Technische Universität Chemnitz, 09107 Chemnitz, Germany, http://www.tu‐chemnitz.de/chemie/anorg/
| | - Tobias Rüffer
- Inorganic Chemistry, Institute of Chemistry, Faculty of Natural Sciences, Technische Universität Chemnitz, 09107 Chemnitz, Germany, http://www.tu‐chemnitz.de/chemie/anorg/
| | - Dieter Schaarschmidt
- Inorganic Chemistry, Institute of Chemistry, Faculty of Natural Sciences, Technische Universität Chemnitz, 09107 Chemnitz, Germany, http://www.tu‐chemnitz.de/chemie/anorg/
| | - Heinrich Lang
- Inorganic Chemistry, Institute of Chemistry, Faculty of Natural Sciences, Technische Universität Chemnitz, 09107 Chemnitz, Germany, http://www.tu‐chemnitz.de/chemie/anorg/
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22
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Lansing JC, Camara JM, Gray DE, Rauchfuss TB. Hydrogen Production Catalyzed by Bidirectional, Biomimetic Models of the [FeFe]-Hydrogenase Active Site. Organometallics 2014; 33:5897-5906. [PMID: 25364093 PMCID: PMC4210170 DOI: 10.1021/om5004013] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Indexed: 12/18/2022]
Abstract
Active site mimics of [FeFe]-hydrogenase are shown to be bidirectional catalysts, producing H2 upon treatment with protons and reducing equivalents. This reactivity complements the previously reported oxidation of H2 by these same catalysts in the presence of oxidants. The complex Fe2(adtBn)(CO)3(dppv)(PFc*Et2 ) ([1]0; adtBn = (SCH2)2NBn, dppv = cis-1,2-bis(diphenylphosphino)ethylene, PFc*Et2 = Et2PCH2C5Me4FeCp*) reacts with excess [H(OEt2)2]BArF4 (BArF4- = B(C6H3-3,5-(CF3)2)4-) to give ∼0.5 equiv of H2 and [Fe2(adtBnH)(CO)3(dppv)(PFc*Et2 )]2+ ([1H]2+). The species [1H]2+ consists of a ferrocenium ligand, an N-protonated amine, and an FeIFeI core. In the presence of additional reducing equivalents in the form of decamethylferrocene (Fc*), hydrogen evolution is catalytic, albeit slow. The related catalyst Fe2(adtBn)(CO)3(dppv)(PMe3) (3) behaves similarly in the presence of Fc*, except that in the absence of excess reducing agent it converts to the catalytically inactive μ-hydride derivative [μ-H3]+. Replacement of the adt in [1]0 with propanedithiolate (pdt) results in a catalytically inactive complex. In the course of synthesizing [FeFe]-hydrogenase mimics, new routes to ferrocenylphosphine ligands and nonamethylferrocene were developed.
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Affiliation(s)
- James C Lansing
- Department of Chemistry, University of Illinois 600 S. Goodwin Avenue Urbana, Illinois 61801, United States
| | - James M Camara
- Department of Chemistry, University of Illinois 600 S. Goodwin Avenue Urbana, Illinois 61801, United States
| | - Danielle E Gray
- Department of Chemistry, University of Illinois 600 S. Goodwin Avenue Urbana, Illinois 61801, United States
| | - Thomas B Rauchfuss
- Department of Chemistry, University of Illinois 600 S. Goodwin Avenue Urbana, Illinois 61801, United States
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23
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Fourie E, van Rensburg JMJ, Swarts JC. Synthesis, crystal structure and comparative electrochemistry of metallocenyldiphenylphosphines of ruthenocene, osmocene, ferrocene and cobaltocenium hexafluorophosphate. J Organomet Chem 2014. [DOI: 10.1016/j.jorganchem.2013.12.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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24
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Planar-chiral phosphino alkenylferrocenes – Synthesis, solid-state structure and electrochemistry. J Organomet Chem 2014. [DOI: 10.1016/j.jorganchem.2013.07.080] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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25
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Triferrocenylsilane and unexpected formation of diferrocenyl(3,3-dimethylbutyl)silane via cleavage and trapping of a tetrahydrofuran fragment. Redox chemistry and synthesis of (Fc)3Si–Co(CO)4 through oxidative addition of the Si–H bond. J Organomet Chem 2014. [DOI: 10.1016/j.jorganchem.2013.07.052] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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26
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Bezuidenhout DI, Fernández I, van der Westhuizen B, Swarts PJ, Swarts JC. Electrochemical and Computational Study of Tungsten(0) Ferrocene Complexes: Observation of the Mono-Oxidized Tungsten(0) Ferrocenium Species and Intramolecular Electronic Interactions. Organometallics 2013. [DOI: 10.1021/om400865m] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Daniela I. Bezuidenhout
- Department of Chemistry, University of Pretoria, Private Bag
X20, Hatfield 0028, Pretoria, South Africa
| | - Israel Fernández
- Departamento de Quı́mica Orgánica
I, Facultad de Ciencias Quı́micas, Universidad Complutense, 28040 Madrid, Spain
| | | | - Pieter J. Swarts
- Chemistry Department, University of the Free State, P.O. Box
339, Bloemfontein 9300, South Africa
| | - Jannie C. Swarts
- Chemistry Department, University of the Free State, P.O. Box
339, Bloemfontein 9300, South Africa
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28
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Wang Y, Rapakousiou A, Chastanet G, Salmon L, Ruiz J, Astruc D. Poly(Biferrocenylethynyl)arene and Bis(biferrocenyl)diynyl Complexes and Their Redox Chemistry. Organometallics 2013. [DOI: 10.1021/om400864q] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Yanlan Wang
- ISM, UMR CNRS N°5255, Univ. Bordeaux, 33405 Talence Cedex, France
| | | | | | - Lionel Salmon
- Laboratoire de Chimie de Coordination, CNRS & Université de Toulouse (UPS, INP), 31077 Toulouse, France
| | - Jaime Ruiz
- ISM, UMR CNRS N°5255, Univ. Bordeaux, 33405 Talence Cedex, France
| | - Didier Astruc
- ISM, UMR CNRS N°5255, Univ. Bordeaux, 33405 Talence Cedex, France
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29
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Buitendach BE, Gągor A, Swarts JC. Electrochemical evidence of intramolecular electronic communication in Zr and Hf phthalocyanines bearing ferrocene-containing β-diketonato axial ligands: structure of [PcHf(FcCOCHCOC6H5)2]. Inorg Chem 2013; 52:10245-57. [PMID: 23971994 DOI: 10.1021/ic302730v] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The series of zirconium(IV) and hafnium(IV) phthalocyanine complexes [PcM(FcCOCHCOR)2] (Pc = phthalocyaninato; M = Zr; R = CF3 (1), CH3 (2), C6H5 (3), Fc ((C5H5)Fe(C5H4), 4), as well as M = Hf ; R = CF3 (5), CH3 (6), C6H5 (7), and Fc (8)) were synthesized. A single-crystal X-ray diffraction analysis of the structure of [PcHf(FcCOCHCOC6H5)2], 7 (Z = 2, space group P1), showed the two axial β-diketonato ligands were orientated in such a way that the ferrocenyl groups were positioned diagonally opposite each other. From the structural determination of 7 it was clear that these complexes have a distorted D4h symmetry at the coordination site of the metal centers, which explains a splitting of the UV-vis Q band into Qx and Qy components with 3 ≤ Δλ(max,Q) ≤ 10 nm. Cyclic and square wave voltammetric studies in CH2Cl2/[N((n)Bu)4][B(C6F5)4] allowed observation of at least three phthalocyaninato macrocycle-based redox couples as well as all (i.e., two or four) well-resolved ferrocenyl couples in 1-8. For M = Zr and R = Fc, formal reduction potentials of the four ferrocenyl groups were found to be E°' = 296, 386, 538, and 687 mV versus free ferrocene. Spectroelectrochemical evidence, UV-vis Q-band maximum wavelengths, and HOMO-LUMO energy gaps as expressed by ΔE°'I-III = ΔE°'wave I - ΔE°'wave III were mutually consistent, indicating that the first phthalocyaninato ring-based oxidation occurs before ferrocenyl oxidations take place. The potential for each redox process was found to be dependent on the sum of β-diketonato R-group group electronegativities, ΣχR. Mathematical relationships for the dependency of E°' on ΣχR for all four observed ring-based redox processes as well as for the ferrocenyl-based redox processes were determined. This allowed prediction of potentials for redox processes that fall outside the workable potential window of the solvent. No significant differences were found between the corresponding redox potentials of zirconium and hafnium analogues bearing the same axial ligands.
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Affiliation(s)
- Blenerhassitt E Buitendach
- Department of Chemistry, University of the Free State , P.O. Box 339, Bloemfontein, 9300, Republic of South Africa
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30
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Tohmé A, Grelaud G, Argouarch G, Roisnel T, Bondon A, Paul F. Triarylphosphine Ligands with Pendant Electron-Rich “[Fe(κ 2-dppe)(η 5-C 5Me 5)(C≡C)]–” Substituents. Inorg Chem 2013; 52:8993-9004. [DOI: 10.1021/ic4011828] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Ayham Tohmé
- Institut des
Sciences Chimiques de Rennes-UMR CNRS 6226, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex,
France
| | - Guillaume Grelaud
- Institut des
Sciences Chimiques de Rennes-UMR CNRS 6226, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex,
France
| | - Gilles Argouarch
- Institut des
Sciences Chimiques de Rennes-UMR CNRS 6226, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex,
France
| | - Thierry Roisnel
- Institut des
Sciences Chimiques de Rennes-UMR CNRS 6226, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex,
France
| | - Arnaud Bondon
- SIM-UMR CNRS 6290, Université de Rennes 1, PRISM-Biosit-CS 34317,
Campus de Villejean, 35043 Rennes Cedex, France
| | - Frédéric Paul
- Institut des
Sciences Chimiques de Rennes-UMR CNRS 6226, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex,
France
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31
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Herrero M, Sevilla R, Casado CM, Losada J, Garcı́a-Armada P, Rodrı́guez-Diéguez A, Briones D, Alonso B. Synthesis and Electrochemistry of ((Diferrocenylsilyl)propyl)- and ((Triferrocenylsilyl)propyl)triethoxysilanes. Organometallics 2013. [DOI: 10.1021/om400387c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Marta Herrero
- Departamento
de Quı́mica Inorgánica, Facultad de
Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain
| | - Raquel Sevilla
- Departamento
de Quı́mica Inorgánica, Facultad de
Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain
| | - Carmen M. Casado
- Departamento
de Quı́mica Inorgánica, Facultad de
Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain
| | - José Losada
- Departamento de Ingeniería
Quı́mica Industrial, Escuela Técnica
Superior de Ingenieros Industriales, Universidad Politécnica de Madrid, 28006-Madrid, Spain
| | - Pilar Garcı́a-Armada
- Departamento de Ingeniería
Quı́mica Industrial, Escuela Técnica
Superior de Ingenieros Industriales, Universidad Politécnica de Madrid, 28006-Madrid, Spain
| | | | - David Briones
- Departamento de
Quı́mica Inorgánica, Facultad de Ciencias, Universidad de Granada, 18071-Granada, Spain
| | - Beatriz Alonso
- Departamento
de Quı́mica Inorgánica, Facultad de
Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain
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32
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Mathur P, Rai DK, Ji RS, Pathak B, Boodida S, Mobin SM. Structural and electrochemical aspects of tris(ferrocenyl/phenyl-ethynyl)phosphine ligated chalcogen bridged iron carbonyl clusters. RSC Adv 2013. [DOI: 10.1039/c3ra44788j] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
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33
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Moberg V, Duquesne R, Contaldi S, Röhrs O, Nachtigall J, Damoense L, Hutton AT, Green M, Monari M, Santelia D, Haukka M, Nordlander E. Efficient cluster-based catalysts for asymmetric hydrogenation of α-unsaturated carboxylic acids. Chemistry 2012; 18:12458-78. [PMID: 22890820 DOI: 10.1002/chem.201200630] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2012] [Indexed: 11/10/2022]
Abstract
The new clusters [H(4)Ru(4)(CO)(10)(μ-1,2-P-P)], [H(4)Ru(4)(CO)(10) (1,1-P-P)] and [H(4)Ru(4)(CO)(11)(P-P)] (P-P=chiral diphosphine of the ferrocene-based Josiphos or Walphos ligand families) have been synthesised and characterised. The crystal and molecular structures of eleven clusters reveal that the coordination modes of the diphosphine in the [H(4)Ru(4)(CO)(10)(μ-1,2-P-P)] clusters are different for the Josiphos and the Walphos ligands. The Josiphos ligands bridge a metal-metal bond of the ruthenium tetrahedron in the "conventional" manner, that is, with both phosphine moieties coordinated in equatorial positions relative to a triangular face of the tetrahedron, whereas the phosphine moieties of the Walphos ligands coordinate in one axial and one equatorial position. The differences in the ligand size and the coordination mode between the two types of ligands appear to be reflected in a relative propensity for isomerisation; in solution, the [H(4)Ru(4)(CO)(10)(1,1-Walphos)] clusters isomerise to the corresponding [H(4)Ru(4)(CO)(10)(μ-1,2-Walphos)] clusters, whereas the Josiphos-containing clusters show no tendency to isomerisation in solution. The clusters have been tested as catalysts for asymmetric hydrogenation of four prochiral α-unsaturated carboxylic acids and the prochiral methyl ester (E)-methyl 2-methylbut-2-enoate. High conversion rates (>94%) and selectivities of product formation were observed for almost all catalysts/catalyst precursors. The observed enantioselectivities were low or nonexistent for the Josiphos-containing clusters and catalyst (cluster) recovery was low, suggesting that cluster fragmentation takes place. On the other hand, excellent conversion rates (99-100%), product selectivities (99-100% in most cases) and good enantioselectivities, reaching 90% enantiomeric excess (ee) in certain cases, were observed for the Walphos-containing clusters, and the clusters could be recovered in good yield after completed catalysis. Results from high-pressure NMR and IR studies, catalyst poisoning tests and comparison of catalytic properties of two [H(4)Ru(4)(CO)(10)(μ-1,2-P-P)] clusters (P-P=Walphos ligands) with the analogous mononuclear catalysts [Ru(P-P)(carboxylato)(2)] suggest that these clusters may be the active catalytic species, or direct precursors of an active catalytic cluster species.
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Affiliation(s)
- Viktor Moberg
- Inorganic Chemistry Research Group, Chemical Physics, Center for Chemistry and Chemical Engineering, Lund University, Box 124, 221 00 Lund, Sweden
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34
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Fundamental study of (ferrocenylethynyl)phosphines: Correlation of steric and electronic effects in C,C cross-coupling reactions. J Organomet Chem 2012. [DOI: 10.1016/j.jorganchem.2012.01.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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35
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von Eschwege KG. Oxidation resilient dithizones – Synthesis, cyclic voltammetry and DFT perspectives. Polyhedron 2012. [DOI: 10.1016/j.poly.2012.03.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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36
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Bruña S, Nieto D, González-Vadillo AM, Perles J, Cuadrado I. Cubic Octasilsesquioxanes, Cyclotetrasiloxanes, and Disiloxanes Maximally Functionalized with Silicon-Bridged Interacting Triferrocenyl Units. Organometallics 2012. [DOI: 10.1021/om300101w] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Sonia Bruña
- Departamento de Química
Inorgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid,
Spain
| | - Daniel Nieto
- Departamento de Química
Inorgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid,
Spain
| | - Ana M González-Vadillo
- Departamento de Química
Inorgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid,
Spain
| | - Josefina Perles
- Servicio Interdepartamental
de Investigación (SIDI), Universidad Autónoma de Madrid, Madrid, Spain
| | - Isabel Cuadrado
- Departamento de Química
Inorgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid,
Spain
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37
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Lohan M, Milde B, Heider S, Speck JM, Krauße S, Schaarschmidt D, Rüffer T, Lang H. Synthesis, Electrochemistry, Spectroelectrochemistry, and Solid-State Structures of Palladium Biferrocenylphosphines and Their Use in C,C Cross-Coupling Reactions. Organometallics 2012. [DOI: 10.1021/om201220w] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Manja Lohan
- Faculty of Science, Institute of
Chemistry, Department of Inorganic
Chemistry, Chemnitz University of Technology, Straße
der Nationen 62, 09111 Chemnitz, Germany
| | - Bianca Milde
- Faculty of Science, Institute of
Chemistry, Department of Inorganic
Chemistry, Chemnitz University of Technology, Straße
der Nationen 62, 09111 Chemnitz, Germany
| | - Silvio Heider
- Faculty of Science, Institute of
Chemistry, Department of Inorganic
Chemistry, Chemnitz University of Technology, Straße
der Nationen 62, 09111 Chemnitz, Germany
| | - J. Matthäus Speck
- Faculty of Science, Institute of
Chemistry, Department of Inorganic
Chemistry, Chemnitz University of Technology, Straße
der Nationen 62, 09111 Chemnitz, Germany
| | - Sabrina Krauße
- Faculty of Science, Institute of
Chemistry, Department of Inorganic
Chemistry, Chemnitz University of Technology, Straße
der Nationen 62, 09111 Chemnitz, Germany
| | - Dieter Schaarschmidt
- Faculty of Science, Institute of
Chemistry, Department of Inorganic
Chemistry, Chemnitz University of Technology, Straße
der Nationen 62, 09111 Chemnitz, Germany
| | - Tobias Rüffer
- Faculty of Science, Institute of
Chemistry, Department of Inorganic
Chemistry, Chemnitz University of Technology, Straße
der Nationen 62, 09111 Chemnitz, Germany
| | - Heinrich Lang
- Faculty of Science, Institute of
Chemistry, Department of Inorganic
Chemistry, Chemnitz University of Technology, Straße
der Nationen 62, 09111 Chemnitz, Germany
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38
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Gericke HJ, Muller AJ, Swarts JC. Electrochemical illumination of intramolecular communication in ferrocene-containing tris-β-diketonato aluminum(III) complexes; cytotoxicity of Al(FcCOCHCOCF3)3. Inorg Chem 2012; 51:1552-61. [PMID: 22272584 DOI: 10.1021/ic201849u] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The series of ferrocene-containing tris-β-diketonato aluminum(III) complexes [Al(FcCOCHCOR)(3)] (R = CF(3), 1; CH(3), 2; C(6)H(5), 3; and Fc = ferrocenyl = Fe(η(5)-C(5)H(5))(η(5)-C(5)H(4)), 4) were synthesized and investigated structurally and electrochemically; complex 1 was subjected to cytotoxicity tests. (1)H NMR-spectroscopy distinguished between the mer and fac isomers of 2 and 3. Complex 1 existed only as the mer isomer. A single crystal X-ray crystallographic determination of the structure of a mer-isomer of Al(FcCOCHCOCF(3))(3), 1, (Z = 4, space group P2(1)2(1)2(1)) demonstrated extensive delocalization of all bonds which explained the pronounced electrochemically observed intramolecular communication between molecular fragments. In contrast to electrochemical studies in CH(2)Cl(2)/[N((n)Bu)(4)][PF(6)], the use of the supporting electrolyte [N((n)Bu)(4)][B(C(6)F(5))(4)] allowed identification of all Fc/Fc(+) electrochemical couples by cyclic and square wave voltammetry for 1-4. For R = Fc, formal reduction potentials of the six ferrocenyl groups were found to be E°' = 33, 123, 304, 432, 583, and 741 mV versus free ferrocene respectively. Complex 1 (IC(50) = 10.6 μmol dm(-3)) was less cytotoxic than the free FcCOCH(2)COCF(3) ligand having IC(50) = 6.8 μmol dm(-3) and approximately 2 orders of magnitude less toxic to human HeLa neoplastic cells than cisplatin (IC(50) = 0.19 μmol dm(-3)).
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Affiliation(s)
- Henno J Gericke
- Department of Chemistry, University of the Free State, P.O. Box 339, Bloemfontein, 9300, Republic of South Africa
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Vidjayacoumar B, Ilango S, Ray MJ, Chu T, Kolpin KB, Andreychuk NR, Cruz CA, Emslie DJH, Jenkins HA, Britten JF. Rigid NON- and NSN-ligand complexes of tetravalent and trivalent uranium: comparison of U–OAr2 and U–SAr2 bonding. Dalton Trans 2012; 41:8175-89. [DOI: 10.1039/c2dt30247k] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Milde B, Schaarschmidt D, Rüffer T, Lang H. Phosphino imidazoles and imidazolium salts for Suzuki C–C coupling reactions. Dalton Trans 2012; 41:5377-90. [DOI: 10.1039/c2dt12322c] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Milde B, Lohan M, Schreiner C, Rüffer T, Lang H. (Metallocenylphosphane)palladium Dichlorides - Synthesis, Electrochemistry and Their Application in C-C Coupling Reactions. Eur J Inorg Chem 2011. [DOI: 10.1002/ejic.201100842] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Erasmus JJ, Conradie J. Electrochemical study of β-diketonatobis(triphenylphosphite)rhodium(I) complexes. Electrochim Acta 2011. [DOI: 10.1016/j.electacta.2011.08.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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The Relationship between the Electrochemical and Chemical Oxidation of Ferrocene-Containing Carbonyl-Phosphane-β-Diketonato-Rhodium(I) Complexes - Cytotoxicity of [Rh(FcCOCHCOPh)(CO)(PPh3)]. Eur J Inorg Chem 2011. [DOI: 10.1002/ejic.201100007] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Man WY, Xia JL, Brown NJ, Farmer JD, Yufit DS, Howard JAK, Liu SH, Low PJ. Spectroscopic and Computational Studies of the Ligand Redox Non-Innocence in Mono- and Binuclear Ruthenium Vinyl Complexes. Organometallics 2011. [DOI: 10.1021/om1010534] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Wing Y. Man
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, U.K
| | - Jian-Long Xia
- Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, People’s Republic of China
| | - Neil J. Brown
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, U.K
| | - Julian D. Farmer
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, U.K
| | - Dmitry S. Yufit
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, U.K
| | | | - Sheng Hua Liu
- Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, People’s Republic of China
| | - Paul J. Low
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, U.K
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Diallo AK, Absalon C, Ruiz J, Astruc D. Ferrocenyl-terminated redox stars: synthesis and electrostatic effects in mixed-valence stabilization. J Am Chem Soc 2010; 133:629-41. [PMID: 21155610 DOI: 10.1021/ja109380u] [Citation(s) in RCA: 130] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A family of rigid ferrocenyl-terminated redox stars has been synthesized--by Negishi coupling, including hexa(ferrocenethynyl)benzene complexes, a dodecaferrocenyl star, and stars with extended rigid tethers--and fully characterized. Cyclic voltammetry (CV) studies of the parent complex hexa(ferrocenylethynyl)benzene, 1, show a single wave for the six-electron oxidation of 1 using Nn-Bu(4)PF(6) as the supporting electrolyte on a Pt anode in CH(2)Cl(2), whereas three distinct two-electron reversible CV waves are observed using Nn-Bu(4)BAr(F)(4) (Ar(F) = 3,5-C(6)H(3)-(CF(3))(2)). The CV of 1,3,5-tris(ferrocenylethynyl)benzene, 11, also shows only one wave for the three-electron transfer with Nn-Bu(4)PF(6) and three one-electron waves using Nn-Bu(4)BAr(F)(4). This confirms the lack of electronic communication between the ferrocenyl groups and a significant electrostatic effect among the oxidized ferrocenyl groups. This effect is not significant between para-ferrocenyl groups in 1,4-bis(ferrocenylethynyl)benzene for which only a single wave is observed even with Nn-Bu(4)BAr(F)(4) as the supporting electrolyte. The para-ferrocenyl substituents are quite independent, which explains that two para-ferrocenyl groups are oxidized at about the same potential in a single CV wave of 1. With the additional steric bulk introduced with a methyl substituent on the ferrocenyl group, however, even the para-methylferrocenyl groups are submitted to a small electrostatic effect splitting the six-electron transfer into six single-electron waves, probably because of the overall steroelectronic constraints. Contrary to 11, 1,3-bis(ferrocenylethynyl)benzene and related complexes with a third, different substituent in the remaining meta position different from a ferrocenylethynyl only show a single two-electron wave using Nn-Bu(4)BAr(F)(4), which is attributed to the transoïd conformation of the ferricinium groups minimizing the electrostatic effect. This shows that, in 11, it is the steric frustration that is responsible for the electrostatic effect, and the same occurs in 1. In several cases, ΔE(p) is much larger than the expected 60 mV value, characterizing a quasi-reversible (i.e., relatively slow) redox process. It is suggested that this slower electron transfer be attributed to conformational rearrangement of the ferrocenyl groups toward the transoïd position in the course of electron transfer. Thus both the thermodynamic and kinetic aspects of the electrostatic factor (isolated from the electronic factor), including the frustration effect, are characterized. The distinction between the electronic communication and through-space electrostatic effect was made possible in all of these complexes in which the absence of wave splitting using a strongly ion-pairing electrolyte shows the absence of significant electronic communication, and was confirmed by the new frustration phenomenon.
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Affiliation(s)
- Abdou K Diallo
- Institut des Sciences Moléculaires, UMR CNRS N°5255, Université Bordeaux 1, 33405 Talence Cedex, France
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Geiger WE, Barrière F. Organometallic electrochemistry based on electrolytes containing weakly-coordinating fluoroarylborate anions. Acc Chem Res 2010; 43:1030-9. [PMID: 20345126 DOI: 10.1021/ar1000023] [Citation(s) in RCA: 259] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Electrochemistry is a powerful tool for the study of oxidative electron-transfer reactions (anodic processes). Since the 1960s, the electrolytes of choice for nonaqueous electrochemistry were relatively small (heptaatomic or smaller) inorganic anions, such as perchlorate, tetrafluoroborate, or hexafluorophosphate. Owing to the similar size-to-charge ratios of these "traditional" anions, structural alterations of the electrolyte anion are not particularly valuable in effecting changes in the corresponding redox reactions. Systematic variations of supporting electrolytes were largely restricted to cathodic processes, in which interactions of anions produced in the reactions are altered by changes in electrolyte cations. A typical ladder involves going from a weakly ion-pairing tetraalkylammonium cation, [N(C(n)H(2n+1))(4)](+), with n > or = 4, to more strongly ion-pairing counterparts with n < 4, and culminating in very strongly ion-pairing alkali metal ions. A new generation of supporting electrolyte salts that incorporate a weakly coordinating anion (WCA) expands anodic applications by providing a dramatically different medium in which to generate positively charged electrolysis products. A chain of electrolyte anions is now available for the control of anodic reactions, beginning with weakly ion-pairing WCAs, progressing through the traditional anions, and culminating in halide ions. Although the electrochemical properties of a number of different WCAs have been reported, the most systematic work involves fluoro- or trifluoromethyl-substituted tetraphenylborate anions (fluoroarylborate anions). In this Account, we focus on tetrakis(perfluorophenyl)borate, [B(C(6)F(5))(4)](-), which has a significantly more positive anodic window than tetrakis[(3,5-bis(trifluoromethyl)phenyl)]borate, [BArF(24)](-), making it suitable in a larger range of anodic oxidations. These WCAs also have a characteristic of specific importance to organometallic redox processes. Many electron-deficient organometallic compounds are subject to nucleophilic attack by the traditional family of electrolyte anions. With a view to testing the scope of the much less nucleophililic WCAs in providing a benign electrolyte anion for the generation of organometallic cation radicals, we carried out a series of studies on transition metal sandwich and half-sandwich compounds. The model compounds were chosen both for their fundamental importance and because their radical cations had been neither isolated nor spectrally characterized, despite many previous electrochemical investigations with traditional anions. The oxidation of prototypical organometallic compounds, such as the sandwich-structured ruthenocene and the piano-stool structured Cr(eta(6)-C(6)H(6))(CO)(3), Mn(eta(5)-C(5)H(5))(CO)(3), Re(eta(5)-C(5)H(5))(CO)(3), and Co(eta(5)-C(5)H(5))(CO)(2), gave the first definitive in situ characterization of their radical cations. In several cases, the kinetic stabilization of the anodic products allowed the identification of dimers or unique dimer radicals having weak metal-metal bonds and provided new preparative options for organometallic systems. In terms of thermodynamic effects, the lower ion-pairing abilities of WCAs and their good solubility in a broad range of solvents, including those of lower polarity, permitted a systematic study that yielded an integrated model of how to use solvent-electrolyte combinations to manipulate the E(1/2) differences of compounds undergoing multiple electron-transfer reactions. Although the efficacy of WCA-based electrolytes in organometallic anodic chemistry is now established, WCAs might further expand applications of organic redox chemistry. Other WCAs, including those derived from carboranes and fluorinated alkoxyaluminates, merit additional studies.
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Affiliation(s)
- William E. Geiger
- Department of Chemistry, University of Vermont, Burlington, Vermont 05445
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Bruña S, González-Vadillo AM, Nieto D, Pastor C, Cuadrado I. Vinyl-Functionalized Silanes and Disiloxanes with Electronically Communicated Ferrocenyl Units. Organometallics 2010. [DOI: 10.1021/om1002733] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | | | - César Pastor
- Laboratorio de Difracción de Rayos X del Servicio Interdepartamental de Investigación, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 29049, Madrid, Spain
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Gericke HJ, Barnard NI, Erasmus E, Swarts JC, Cook MJ, Aquino MA. Solvent and electrolyte effects in enhancing the identification of intramolecular electronic communication in a multi redox-active diruthenium tetraferrocenoate complex, a triple-sandwiched dicadmium phthalocyanine and a ruthenocene-containing β-diketone. Inorganica Chim Acta 2010. [DOI: 10.1016/j.ica.2010.03.031] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Augusta Antunes M, Namorado S, de Azevedo CG, Amélia Lemos M, Teresa Duarte M, Ascenso JR, Martins AM. Pentabenzylcyclopentadienyl molybdenum and tungsten hydrides: Syntheses, structures and electrochemistry of [MHCpBz(CO)2(L)] (L=CO, PMe3, PPh3). J Organomet Chem 2010. [DOI: 10.1016/j.jorganchem.2010.02.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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