1
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Kosloski-Oh S, Knight KD, Fieser ME. Enhanced Control of Isoprene Polymerization with Trialkyl Rare Earth Metal Complexes through Neutral Donor Support. Inorg Chem 2024; 63:9464-9477. [PMID: 38063304 PMCID: PMC11134520 DOI: 10.1021/acs.inorgchem.3c03161] [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: 09/08/2023] [Revised: 11/14/2023] [Accepted: 11/20/2023] [Indexed: 05/28/2024]
Abstract
The development of catalysts for stereospecific polymerization of 1,3-dienes is an area of interest due to the robust nature of poly(1,3-diene)s' physical and mechanical properties, as well as the material's versatility in many applications. Dialkyl rare earth metal complexes supported by a diverse cast of ligand frameworks are selective for the polymerization of 1,3-dienes and are an exciting option for examination. However, development in this area has been hampered by the focus on complex catalyst systems that are costly to make. In this study, we synthesize a series of simple homoleptic trialkyl rare earth metal precatalysts and highlight their efficacy for isoprene polymerization using 1 or 2 equiv of [Ph3C][B(C6F5)4] activator. We investigated the addition of commercially available in situ donors, leading to the identification of triphenylphosphine as an ideal support to enhance the dispersity control and prevent loss of catalyst activity. We demonstrated how the activation and reaction conditions, including the order/time of reagent addition and donor electronics, had a major impact on the rate, control, and selectivity for the polymerization of 1,3-dienes. Further interrogation of the catalyst system signals the crucial role of triphenylphosphine in providing enhanced stability and control in this living catalyst system.
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Affiliation(s)
- Sophia
C. Kosloski-Oh
- Department
of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Kai D. Knight
- Department
of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Megan E. Fieser
- Department
of Chemistry, University of Southern California, Los Angeles, California 90089, United States
- Wrigley
Institute for Environment and Sustainability, University of Southern California, Los Angeles, California 90089, United States
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2
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Tortajada A, Bole LJ, Mu M, Stanford M, Peñas-Defrutos MN, García-Melchor M, Hevia E. Sodium mediated deprotonative borylation of arenes using sterically demanding B(CH 2SiMe 3) 3: unlocking polybasic behaviour and competing lateral borane sodiation. Chem Sci 2023; 14:6538-6545. [PMID: 37350840 PMCID: PMC10283504 DOI: 10.1039/d3sc01705b] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 05/04/2023] [Indexed: 06/24/2023] Open
Abstract
The deprotonative metalation of organic molecules has become a convenient route to prepare functionalised aromatic substrates. Amongst the different metallating reagents available, sodium bases have recently emerged as a more sustainable and powerful alternative to their lithium analogues. Here we report the study of the sterically demanding electrophilic trap B(CH2SiMe3)3 for the deprotonative borylation of arenes using NaTMP (TMP = 2,2,6,6-tetramethylpiperidide) in combination with tridentate Lewis donor PMDETA (PMDETA = N,N,N',N'',N''-pentamethyldiethylenetriamine). Using anisole and benzene as model substrates, unexpected polybasic behaviour has been uncovered, which enables the formal borylation of two equivalents of the relevant arene. The combination of X-ray crystallographic and NMR monitoring studies with DFT calculations has revealed that while the first B-C bond forming process takes place via a sodiation/borylation sequence to furnish [(PMDETA)NaB(Ar)(CH2SiMe3)3] species, the second borylation step is facilitated by the formation of a borata-alkene intermediate, without the need of an external base. For non-activated benzene, it has also been found that under stoichimetric conditions the lateral sodiation of B(CH2SiMe3)3 becomes a competitive reaction pathway furnishing a novel borata-alkene complex. Showing a clear alkali-metal effect, the use of the sodium base is key to access this reactivity, while the metalation/borylation of the amine donor PMDETA is observed instead when LiTMP is used.
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Affiliation(s)
- Andreu Tortajada
- Department für Chemie und Biochemie, Universität Bern Freiestrasse 3 3012 Bern Switzerland
| | - Leonie J Bole
- Department für Chemie und Biochemie, Universität Bern Freiestrasse 3 3012 Bern Switzerland
| | - Manting Mu
- School of Chemistry, CRANN and AMBER Research Centres, Trinity College Dublin College Green Dublin 2 Ireland
| | - Martin Stanford
- Department für Chemie und Biochemie, Universität Bern Freiestrasse 3 3012 Bern Switzerland
| | - Marconi N Peñas-Defrutos
- School of Chemistry, CRANN and AMBER Research Centres, Trinity College Dublin College Green Dublin 2 Ireland
- IU CINQUIMA/Química Inorgánica, Facultad de Ciencias, Universidad de Valladolid 47071-Valladolid Spain
| | - Max García-Melchor
- School of Chemistry, CRANN and AMBER Research Centres, Trinity College Dublin College Green Dublin 2 Ireland
| | - Eva Hevia
- Department für Chemie und Biochemie, Universität Bern Freiestrasse 3 3012 Bern Switzerland
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3
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Mortis A, Maichle-Mössmer C, Anwander R. Distinct Reactivity of Trimethylytterbium toward AlMe 3 and GaMe 3 : Synthesis of Donor-Stabilized Dimethylytterbium. Chemistry 2023; 29:e202203824. [PMID: 36688627 DOI: 10.1002/chem.202203824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 01/13/2023] [Accepted: 01/23/2023] [Indexed: 01/24/2023]
Abstract
Me3 TACN (1,4,7-trimethyl-1,4,7-triazacyclononane)-stabilized trimethylytterbium was obtained via a salt-metathesis protocol employing [(Me3 TACN)YbCl3 ] and methyllithium. Complex [(Me3 TACN)YbMe3 ] seems not to engage in redox chemistry with potassium graphite and is thermally quite stable in the solid state. Treatment of trivalent [(Me3 TACN)YbMe3 ] with 3 equiv. of AlMe3 afforded divalent tetramethylaluminate complex [(Me3 TACN)Yb(AlMe4 )2 ]. The reaction of [(Me3 TACN)YbMe3 ] with GaMe3 in THF gave trivalent ion pair [(Me3 TACN)YbMe2 (thf)][GaMe4 ], which is susceptible to reduction with KC8 . The thermally very labile divalent [(Me3 TACN)YbMe(μ-Me)]2 is the first discrete donor adduct of a divalent dimethyl rare-earth-metal complex.
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Affiliation(s)
- Alexandros Mortis
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Cäcilia Maichle-Mössmer
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Reiner Anwander
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
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4
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Oswald AD, Verrieux L, Breuil PAR, Olivier-Bourbigou H, Thuilliez J, Vaultier F, Taoufik M, Perrin L, Boisson C. Cationic Phenoxyimine Complexes of Yttrium: Synthesis, Characterization, and Living Polymerization of Isoprene. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Alexis D. Oswald
- Université de Lyon, Université Claude Bernard Lyon 1, CPE Lyon, CNRS, UMR 5128, Catalysis, Polymerization, Processes and Materials (CP2M), 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France
| | - Ludmilla Verrieux
- Université de Lyon, Université Claude Bernard Lyon I, CNRS, INSA, CPE, UMR 5246, ICBMS, 1 rue Victor Grignard, F-69622 Villeurbanne cedex, France
- Michelin CP2M ICBMS Joint Research Laboratory, ChemistLab, F-69616 Villeurbanne, France
| | - Pierre-Alain R. Breuil
- IFP Energies nouvelles, Rond-point de l’échangeur de Solaize, BP 3, 69360 Solaize, France
| | | | - Julien Thuilliez
- Manufacture Michelin, 23 place Carmes Déchaux, F-63000 Clermont-Ferrand, France
| | - Florent Vaultier
- Manufacture Michelin, 23 place Carmes Déchaux, F-63000 Clermont-Ferrand, France
- Michelin CP2M ICBMS Joint Research Laboratory, ChemistLab, F-69616 Villeurbanne, France
| | - Mostafa Taoufik
- Université de Lyon, Université Claude Bernard Lyon 1, CPE Lyon, CNRS, UMR 5128, Catalysis, Polymerization, Processes and Materials (CP2M), 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France
- Michelin CP2M ICBMS Joint Research Laboratory, ChemistLab, F-69616 Villeurbanne, France
| | - Lionel Perrin
- Université de Lyon, Université Claude Bernard Lyon I, CNRS, INSA, CPE, UMR 5246, ICBMS, 1 rue Victor Grignard, F-69622 Villeurbanne cedex, France
- Michelin CP2M ICBMS Joint Research Laboratory, ChemistLab, F-69616 Villeurbanne, France
| | - Christophe Boisson
- Université de Lyon, Université Claude Bernard Lyon 1, CPE Lyon, CNRS, UMR 5128, Catalysis, Polymerization, Processes and Materials (CP2M), 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France
- Michelin CP2M ICBMS Joint Research Laboratory, ChemistLab, F-69616 Villeurbanne, France
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5
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Bonath M, Schädle D, Maichle-Mössmer C, Anwander R. The Alkylaluminate/Gallate Trap: Metalation of Benzene by Heterobimetallic Yttrocene Complexes [Cp* 2Y(MMe 3R)] (M = Al, Ga). Inorg Chem 2021; 60:14952-14968. [PMID: 34514777 DOI: 10.1021/acs.inorgchem.1c02349] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Yttrocene derivatives [Cp*2Y(MMe4)] (Cp* = C5Me5; M = Al, Ga) and Cp*2Y[Me3Al{B(NDippCH)2}] (Dipp = C6H3iPr2-2,6) deprotonate benzene at elevated temperatures via the release of methane. The formation of [Cp*2Y(Me2MPh2)] (M = Al, Ga), Cp*2Y(MPh4) (M = Al, Ga), Cp*2Y[Me2AlPh{B(NDippCH)2}], and Cp*2Y[AlPh3{B(NDippCH)2}] can be controlled via the temperature applied. The activation temperature and formation of the coordinatively unsaturated "reactive" [Cp*2YMe] strongly depend on the coordination strength of the displaceable Lewis acids [AlMe3]2, GaMe3, and [Me2Al{B(NDippCH)2}]2. Hence, [Cp*2Y(AlMe4)] requires temperatures above 100 °C to metalate benzene, while Cp*2Y[AlMe3{B(NDippCH)2}] undergoes C-H-bond activation even at ambient temperatures. A kinetic deuterium isotope effect was observed for the reactions in C6D6 solutions. Distinct differences in the stabilities of the bulky Group 13 anions ([Me2MPh2]-, [MPh4]-, [Me3Al{B(NDippCH)2}]-, [Me2AlPh{B(NDippCH)2}]-, and [AlPh3{B(NDippCH)2}]-) are assessed by detailed studies of the coordination chemistry with tetrahydrofuran (THF) and by variable-temperature 1H NMR spectroscopy. Thus, increased steric bulk or a reduced Lewis acidity of the Group 13 metal center promote temperature-sensitive dissociation of trivalent Group 13 alkyl entities. Consequently, compound Cp*2Y[AlPh3{B(NDippCH)2}] was found to engage in a dissociation equilibrium with [Cp*2YPh] and AlPh2{B(NDippCH)2} in a C6D6 solution at ambient temperature. The reaction of Cp*2Y[AlPh3{B(NDippCH)2}] with THF results in the concomitant formation of monometallic Cp*2YPh(THF) and the solvent-separated ion pair [Cp*2Y(THF)2][AlPh3{B(NDippCH)2}].
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Affiliation(s)
- Martin Bonath
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, Tübingen 72076, Germany
| | - Dorothea Schädle
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, Tübingen 72076, Germany
| | - Cäcilia Maichle-Mössmer
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, Tübingen 72076, Germany
| | - Reiner Anwander
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, Tübingen 72076, Germany
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6
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Seymen A, Münch A, Orr SA, Herbst-Irmer R, Mulvey RE, Strohmann C, Stalke D. When Electrons Step in: Polarizing Effects Explored with Triisobutylaluminum. Inorg Chem 2021; 60:2872-2877. [PMID: 33641334 DOI: 10.1021/acs.inorgchem.0c03471] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
High-resolution X-ray diffraction data of triisobutylaluminum were collected, and unexpected structural features were observed, hinting toward yet unnoticed polarization effects. To approach these, a multipole refinement using the Hansen and Coppens method, followed by a topological analysis using Bader's quantum theory of atoms in molecules, was employed. The electron localization function based on density functional theory calculations supported the experimental findings. Thereby, unobserved electron shifts within the isobutyl group become detectable. It is shown that the impact of this electron shift is dependent mainly on whether the iBu substituent of the homoleptic triisobutylaluminum dimer [AliBu3]2 (1) is connected by a directional (σ) or a multicenter (μ) bond to the metal. The effect found is assumed not only to be of paramount importance for organoaluminum compounds, widely used in synthesis and in the industrial value chain, but also to be present in organometallic chemistry in general.
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Affiliation(s)
- Andreas Seymen
- Institut für Anorganische Chemie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, 44227 Dortmund, Germany
| | - Annika Münch
- Institut für Anorganische Chemie, Georg-August Universität Göttingen, Tammannstrasse 4, 37077 Göttingen, Germany
| | - Samantha A Orr
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, U.K
| | - Regine Herbst-Irmer
- Institut für Anorganische Chemie, Georg-August Universität Göttingen, Tammannstrasse 4, 37077 Göttingen, Germany
| | - Robert E Mulvey
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, U.K
| | - Carsten Strohmann
- Institut für Anorganische Chemie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, 44227 Dortmund, Germany
| | - Dietmar Stalke
- Institut für Anorganische Chemie, Georg-August Universität Göttingen, Tammannstrasse 4, 37077 Göttingen, Germany
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7
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Oswald AD, El Bouhali A, Chefdeville E, Breuil PAR, Olivier-Bourbigou H, Thuilliez J, Vaultier F, De Mallmann A, Taoufik M, Perrin L, Boisson C. Monocationic Bis-Alkyl and Bis-Allyl Yttrium Complexes: Synthesis, 89Y NMR Characterization, Ethylene or Isoprene Polymerization, and Modeling. Organometallics 2021. [DOI: 10.1021/acs.organomet.0c00709] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Alexis D. Oswald
- Univ Lyon, Université Claude Bernard Lyon 1, CPE Lyon, CNRS, UMR 5265, Chemistry, Catalysis, Polymers and Processes (C2P2), 43 Bd du 11 Novembre 1918, 69616 Villeurbanne, France
| | - Aymane El Bouhali
- Univ Lyon, Université Claude Bernard Lyon I, CNRS, INSA, CPE, UMR 5246, ICBMS, 1 rue Victor Grignard, F-69622 Villeurbanne cedex, France
| | - Emmanuel Chefdeville
- Univ Lyon, Université Claude Bernard Lyon I, CNRS, INSA, CPE, UMR 5246, ICBMS, 1 rue Victor Grignard, F-69622 Villeurbanne cedex, France
| | - Pierre-Alain R. Breuil
- IFP Energies nouvelles, Rond-point de l’échangeur de Solaize, BP 3, 69360 Solaize, France
| | | | - Julien Thuilliez
- Manufacture Michelin, 23 places Carmes Déchaux, F-63000 Clermont-Ferrand, France
| | - Florent Vaultier
- Manufacture Michelin, 23 places Carmes Déchaux, F-63000 Clermont-Ferrand, France
| | - Aimery De Mallmann
- Univ Lyon, Université Claude Bernard Lyon 1, CPE Lyon, CNRS, UMR 5265, Chemistry, Catalysis, Polymers and Processes (C2P2), 43 Bd du 11 Novembre 1918, 69616 Villeurbanne, France
| | - Mostafa Taoufik
- Univ Lyon, Université Claude Bernard Lyon 1, CPE Lyon, CNRS, UMR 5265, Chemistry, Catalysis, Polymers and Processes (C2P2), 43 Bd du 11 Novembre 1918, 69616 Villeurbanne, France
| | - Lionel Perrin
- Univ Lyon, Université Claude Bernard Lyon I, CNRS, INSA, CPE, UMR 5246, ICBMS, 1 rue Victor Grignard, F-69622 Villeurbanne cedex, France
| | - Christophe Boisson
- Univ Lyon, Université Claude Bernard Lyon 1, CPE Lyon, CNRS, UMR 5265, Chemistry, Catalysis, Polymers and Processes (C2P2), 43 Bd du 11 Novembre 1918, 69616 Villeurbanne, France
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8
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Uzelac M, Hernán-Gómez A, Armstrong DR, Kennedy AR, Hevia E. Rational synthesis of normal, abnormal and anionic NHC-gallium alkyl complexes: structural, stability and isomerization insights. Chem Sci 2015; 6:5719-5728. [PMID: 29910864 PMCID: PMC5975842 DOI: 10.1039/c5sc02086g] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Accepted: 07/03/2015] [Indexed: 11/21/2022] Open
Abstract
Advancing the rational design of main-group N-heterocyclic carbene complexes, this study reports the synthesis, X-ray crystallographic and NMR spectroscopic characterisation of a novel series of Ga complexes containing neutral or anionic NHC ligands using the unsaturated carbene IPr (IPr = 1,3-bis-(2,6-di-isopropylphenyl)imidazol-2-ylidene). Starting from normal adduct GaR3·IPr (1) (R = CH2SiMe3), the addition of polar LiR led to the formation of NHC-stabilised gallate species IPr·LiGaR4 (2), resulting from co-complexation of the single-metal species. Contrastingly, reversing the order of addition of these organometallic reagents, by treating unsaturated free IPr, first with LiR followed by GaR3, furnished novel heteroleptic gallate (THF)2Li[:C{[N(2,6-iPr2C6H3)]2CHCGa(CH2SiMe3)3}] (3), which contains an anionic NHC ligand acting as an unsymmetrical bridge between the two metals, coordinating through its abnormal C4 position to Ga and through its normal C2 position to Li. Electrophilic interception studies of 3 using methyl triflate (MeOTf), methanol and imidazolium salt (IMes·HCl) led to the isolation and structural elucidation of the two novel neutral abnormal NHC (aNHC) complexes [CH3C{[N(2,6-iPr2C6H3)]2CHCGa(CH2SiMe3)3}] (4) and aIPr·GaR3 (5) (aIPr = HC{[N(2,6-iPr2C6H3)]2CHC}). These studies disclose the preference of the anionic IPr ligand present in 3 to react with electrophiles via its C2 position, leaving its Ga-C4 bond intact. Abnormal complex 5 can also be accessed by a thermally induced rearrangement of its normal isomer 1. Combining NMR spectroscopic and kinetic studies with DFT calculations, new light has been shed on this intriguing transformation, which suggests that it occurs via a dissociative mechanism, highlighting the importance of the donor ability of the solvent used in these thermal isomerizations as well as the steric bulk of the substituents on the NHC and the Ga reagent. These findings intimate that relief of the steric hindrance around Ga by forming an abnormal complex is a key driving force behind these rearrangements.
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Affiliation(s)
- Marina Uzelac
- WestCHEM , Department of Pure and Applied Chemistry , University of Strathclyde , Glasgow , G1 1XL , UK .
| | - Alberto Hernán-Gómez
- WestCHEM , Department of Pure and Applied Chemistry , University of Strathclyde , Glasgow , G1 1XL , UK .
| | - David R Armstrong
- WestCHEM , Department of Pure and Applied Chemistry , University of Strathclyde , Glasgow , G1 1XL , UK .
| | - Alan R Kennedy
- WestCHEM , Department of Pure and Applied Chemistry , University of Strathclyde , Glasgow , G1 1XL , UK .
| | - Eva Hevia
- WestCHEM , Department of Pure and Applied Chemistry , University of Strathclyde , Glasgow , G1 1XL , UK .
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9
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Arndt S, Kramer MU, Fegler W, Nakajima Y, Del Rosal I, Poteau R, Spaniol TP, Maron L, Okuda J. Yttrium Dihydride Cation [YH2(THF)2]+n: Aggregate Formation and Reaction with (NNNN)-Type Macrocycles. Organometallics 2015. [DOI: 10.1021/acs.organomet.5b00422] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Stefan Arndt
- Institute
of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, D-52056 Aachen, Germany
| | - Mathias U. Kramer
- Institute
of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, D-52056 Aachen, Germany
| | - Waldemar Fegler
- Institute
of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, D-52056 Aachen, Germany
| | - Yumiko Nakajima
- Institute
of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, D-52056 Aachen, Germany
| | - Iker Del Rosal
- Université de Toulouse, CNRS, INSA, UPS, UMR 5215,
LPCNO, 135 avenue de Rangueil, F-31077 Toulouse, France
| | - Romuald Poteau
- Université de Toulouse, CNRS, INSA, UPS, UMR 5215,
LPCNO, 135 avenue de Rangueil, F-31077 Toulouse, France
| | - Thomas P. Spaniol
- Institute
of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, D-52056 Aachen, Germany
| | - Laurent Maron
- Université de Toulouse, CNRS, INSA, UPS, UMR 5215,
LPCNO, 135 avenue de Rangueil, F-31077 Toulouse, France
| | - Jun Okuda
- Institute
of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, D-52056 Aachen, Germany
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10
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Li W, Xue M, Zhang Y, Yao Y, Shen Q. Direct Synthesis of Ion-pair Lanthanide Borohydrides and their High Activity for Polymerization ofL-Lactide and ϵ-Caprolactone. Z Anorg Allg Chem 2014. [DOI: 10.1002/zaac.201300380] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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11
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Li X, Wang X, Tong X, Zhang H, Chen Y, Liu Y, Liu H, Wang X, Nishiura M, He H, Lin Z, Zhang S, Hou Z. Aluminum Effects in the Syndiospecific Copolymerization of Styrene with Ethylene by Cationic Fluorenyl Scandium Alkyl Catalysts. Organometallics 2013. [DOI: 10.1021/om3011036] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Xiaofang Li
- Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry, Beijing Institute of Technology, 5 South Zhongguancun
Street, Haidian District, Beijing 100081, People’s Republic
of China
| | - Xiaoying Wang
- Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry, Beijing Institute of Technology, 5 South Zhongguancun
Street, Haidian District, Beijing 100081, People’s Republic
of China
| | - Xin Tong
- Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry, Beijing Institute of Technology, 5 South Zhongguancun
Street, Haidian District, Beijing 100081, People’s Republic
of China
| | - Hongxia Zhang
- Organometallic
Chemistry Laboratory and Advanced Catalyst Research Team, RIKEN Advanced Science Institute, Hirosawa 2-1, Wako,
Saitama 351-0198, Japan
| | - Yuanyuan Chen
- Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry, Beijing Institute of Technology, 5 South Zhongguancun
Street, Haidian District, Beijing 100081, People’s Republic
of China
| | - Ying Liu
- Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry, Beijing Institute of Technology, 5 South Zhongguancun
Street, Haidian District, Beijing 100081, People’s Republic
of China
| | - Hui Liu
- Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry, Beijing Institute of Technology, 5 South Zhongguancun
Street, Haidian District, Beijing 100081, People’s Republic
of China
| | - Xiaojie Wang
- Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry, Beijing Institute of Technology, 5 South Zhongguancun
Street, Haidian District, Beijing 100081, People’s Republic
of China
| | - Masayoshi Nishiura
- Organometallic
Chemistry Laboratory and Advanced Catalyst Research Team, RIKEN Advanced Science Institute, Hirosawa 2-1, Wako,
Saitama 351-0198, Japan
| | - Huan He
- Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry, Beijing Institute of Technology, 5 South Zhongguancun
Street, Haidian District, Beijing 100081, People’s Republic
of China
| | - Zhenguo Lin
- Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry, Beijing Institute of Technology, 5 South Zhongguancun
Street, Haidian District, Beijing 100081, People’s Republic
of China
| | - Shaowen Zhang
- Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry, Beijing Institute of Technology, 5 South Zhongguancun
Street, Haidian District, Beijing 100081, People’s Republic
of China
| | - Zhaomin Hou
- Organometallic
Chemistry Laboratory and Advanced Catalyst Research Team, RIKEN Advanced Science Institute, Hirosawa 2-1, Wako,
Saitama 351-0198, Japan
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Armstrong DR, Brammer E, Cadenbach T, Hevia E, Kennedy AR. Co-complexation Syntheses, Structural Characterization, and DFT Studies of a Novel Series of Polymeric Alkali-Metal Tetraorganogallates. Organometallics 2013. [DOI: 10.1021/om3009469] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- David R. Armstrong
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, U.K., G1 1XL
| | - Elanor Brammer
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, U.K., G1 1XL
| | - Thomas Cadenbach
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, U.K., G1 1XL
| | - Eva Hevia
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, U.K., G1 1XL
| | - Alan R. Kennedy
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, U.K., G1 1XL
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Hernán-Gómez A, Martín A, Mena M, Santamaría C. Contact and solvent-separated ion pair aluminium “ate” complexes on a titanium oxide molecular model. Dalton Trans 2013; 42:5076-84. [DOI: 10.1039/c3dt32725f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Gómez-Pantoja M, Gómez-Sal P, Hernán-Gómez A, Martín A, Mena M, Santamaría C. Co-complexation of lithium gallates on the titanium molecular oxide {[Ti(η5-C5Me5)(μ-O)}3(μ3-CH)]. Inorg Chem 2012; 51:8964-72. [PMID: 22845551 DOI: 10.1021/ic301057u] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Amide and lithium aryloxide gallates [Li(+){RGaPh(3)}(-)] (R = NMe(2), O-2,6-Me(2)C(6)H(3)) react with the μ(3)-alkylidyne oxoderivative ligand [{Ti(η(5)-C(5)Me(5))(μ-O)}(3)(μ(3)-CH)] (1) to afford the gallium-lithium-titanium cubane complexes [{Ph(3)Ga(μ-R)Li}{Ti(η(5)-C(5)Me(5))(μ-O)}(3)(μ(3)-CH)] [R = NMe(2) (3), O-2,6-Me(2)C(6)H(3) (4)]. The same complexes can be obtained by treatment of the [Ph(3)Ga(μ(3)-O)(3){Ti(η(5)-C(5)Me(5))}(3)(μ(3)-CH)] (2) adduct with the corresponding lithium amide or aryloxide, respectively. Complex 3 evolves with formation of 5 as a solvent-separated ion pair constituted by the lithium dicubane cationic species [Li{(μ(3)-O)(3)Ti(3)(η(5)-C(5)Me(5))(3)(μ(3)-CH)}(2)](+) together with the anionic [(GaPh(3))(2)(μ-NMe(2))](-) unit. On the other hand, the reaction of 1 with Li(p-MeC(6)H(4)) and GaPh(3) leads to the complex [Li{(μ(3)-O)(3)Ti(3)(η(5)-C(5)Me(5))(3)(μ(3)-CH)}(2)][GaLi(p-MeC(6)H(4))(2)Ph(3)] (6). X-ray diffraction studies were performed on 1, 2, 4, and 5, while trials to obtain crystals of 6 led to characterization of [Li{(μ(3)-O)(3)Ti(3)(η(5)-C(5)Me(5))(3)(μ(3)-CH)}(2)][PhLi(μ-C(6)H(5))(2)Ga(p-MeC(6)H(4))Ph] 6a.
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Affiliation(s)
- María Gómez-Pantoja
- Departamento de Química Inorgánica, Universidad de Alcalá, Campus Universitario, 28871 Alcalá de Henares, Madrid, Spain
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Lichtenberg C, Spaniol TP, Okuda J. Bis(allyl)gallium cation, tris(allyl)gallium, and tetrakis(allyl)gallate: synthesis, characterization, and reactivity. Inorg Chem 2012; 51:2254-62. [PMID: 22268716 DOI: 10.1021/ic202293t] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
A series of cationic, neutral, and anionic allylgallium complexes has been isolated and fully characterized. It includes neutral [Ga(η(1)-C(3)H(5))(3)(L)] (1, L = THF; 2, L = OPPh(3)), cationic [Ga(η(1)-C(3)H(5))(2)(THF)(2)](+)[A](-) (3, [A](-) = [B(C(6)F(5))(4)](-); 4, [A](-) = [B(C(6)H(3)Cl(2))(4)](-)), as well as anionic [Cat](+)[Ga(η(1)-C(3)H(5))(4)](-) (5, [Cat](+) = K(+); 6, [Cat](+) = [K(dibenzo-18-c-6](+); 7, [Cat](+) = [PPh(4)](+)). Binding modes of the allyl ligand in solution and in the solid state have been studied comparatively. Single crystal X-ray analyses revealed a four-coordinate neutral gallium center in 2, a five-coordinate cationic gallium center in 4 and [4·THF], and a four-coordinate anionic gallium center with a bridging μ(2)-η(1):η(2) coordination mode of the allyl ligand in 6. The reactivity of this series of allylgallium complexes toward benzophenone and N-heteroaromatics has been investigated. Counterion effects have also been studied. Reactions of 1 and 5 with isoquinoline revealed the first examples of organogallium complexes reacting under 1,2-insertion with pyridine derivatives.
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Affiliation(s)
- Crispin Lichtenberg
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, D-52056 Aachen, Germany
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Zimmermann M, Anwander R. Homoleptic Rare-Earth Metal Complexes Containing Ln−C σ-Bonds. Chem Rev 2010; 110:6194-259. [DOI: 10.1021/cr1001194] [Citation(s) in RCA: 232] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Melanie Zimmermann
- Department of Chemistry, University of Bergen, Allégaten 41, 5007 Bergen, Norway, and Institut für Anorganische Chemie, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Reiner Anwander
- Department of Chemistry, University of Bergen, Allégaten 41, 5007 Bergen, Norway, and Institut für Anorganische Chemie, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
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Robert D, Abinet E, Spaniol TP, Okuda J. Cationic allyl complexes of the rare-earth metals: synthesis, structural characterization, and 1,3-butadiene polymerization catalysis. Chemistry 2010; 15:11937-47. [PMID: 19784969 DOI: 10.1002/chem.200901616] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Monocationic bis-allyl complexes [Ln(eta(3)-C(3)H(5))(2)(thf)(3)](+)[B(C(6)X(5))(4)](-) (Ln = Y, La, Nd; X = H, F) and dicationic mono-allyl complexes of yttrium and the early lanthanides [Ln(eta(3)-C(3)H(5))(thf)(6)](2+)[BPh(4)](2)(-) (Ln = La, Nd) were prepared by protonolysis of the tris-allyl complexes [Ln(eta(3)-C(3)H(5))(3)(diox)] (Ln = Y, La, Ce, Pr, Nd, Sm; diox = 1,4-dioxane) isolated as a 1,4-dioxane-bridged dimer (Ln = Ce) or THF adducts [Ln(eta(3)-C(3)H(5))(3)(thf)(2)] (Ln = Ce, Pr). Allyl abstraction from the neutral tris-allyl complex by a Lewis acid, ER(3) (Al(CH(2)SiMe(3))(3), BPh(3)) gave the ion pair [Ln(eta(3)-C(3)H(5))(2)(thf)(3)](+)[ER(3)(eta(1)-CH(2)CH=CH(2))](-) (Ln = Y, La; ER(3) = Al(CH(2)SiMe(3))(3), BPh(3)). Benzophenone inserts into the La-C(allyl) bond of [La(eta(3)-C(3)H(5))(2)(thf)(3)](+)[BPh(4)](-) to form the alkoxy complex [La{OCPh(2)(CH(2)CH=CH(2))}(2)(thf)(3)](+)[BPh(4)](-). The monocationic half-sandwich complexes [Ln(eta(5)-C(5)Me(4)SiMe(3))(eta(3)-C(3)H(5))(thf)(2)](+)[B(C(6)X(5))(4)](-) (Ln = Y, La; X = H, F) were synthesized from the neutral precursors [Ln(eta(5)-C(5)Me(4)SiMe(3))(eta(3)-C(3)H(5))(2)(thf)] by protonolysis. For 1,3-butadiene polymerization catalysis, the yttrium-based systems were more active than the corresponding lanthanum or neodymium homologues, giving polybutadiene with approximately 90% 1,4-cis stereoselectivity.
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Affiliation(s)
- Dominique Robert
- Institut für Anorganische Chemie, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany
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Dietrich HM, Maichle-Mössmer C, Anwander R. Donor-assisted tetramethylaluminate/gallate exchange in organolanthanide complexes: pushing the limits of Pearson's HSAB concept. Dalton Trans 2010; 39:5783-5. [DOI: 10.1039/c0dt00383b] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Tetramethylaluminate and Tetramethylgallate Coordination in Rare-Earth Metal Half-Sandwich and Metallocene Complexes. Organometallics 2009. [DOI: 10.1021/om9007168] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Wiecko M, Roesky PW. A Cationic Bis(phosphiniminomethanide) Europium(II) Complex. Organometallics 2009. [DOI: 10.1021/om800989x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Michal Wiecko
- Institut für Chemie and Biochemie, Freie Universität Berlin, Fabeckstrasse 34-36, 14195 Berlin, Germany, and Institut für Anorganische Chemie, Universität Karlsruhe, Engesserstrasse 15, 76128 Karlsruhe, Germany
| | - Peter W. Roesky
- Institut für Chemie and Biochemie, Freie Universität Berlin, Fabeckstrasse 34-36, 14195 Berlin, Germany, and Institut für Anorganische Chemie, Universität Karlsruhe, Engesserstrasse 15, 76128 Karlsruhe, Germany
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Kramer MU, Robert D, Arndt S, Zeimentz PM, Spaniol TP, Yahia A, Maron L, Eisenstein O, Okuda J. Cationic methyl complexes of the rare-earth metals: an experimental and computational study on synthesis, structure, and reactivity. Inorg Chem 2008; 47:9265-78. [PMID: 18816050 DOI: 10.1021/ic801259n] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Synthesis, structure, and reactivity of two families of rare-earth metal complexes containing discrete methyl cations [LnMe(2-x)(thf)n]((1+x)+) (x = 0, 1; thf = tetrahydrofuran) have been studied. As a synthetic equivalent for the elusive trimethyl complex [LnMe3], lithium methylates of the approximate composition [Li3LnMe6(thf)n] were prepared by treating rare-earth metal trichlorides [LnCl3(thf)n] with 6 equiv of methyllithium in diethyl ether. Heteronuclear complexes of the formula [Li3Ln2Me9L(n)] (Ln = Sc, Y, Tb; L = Et2O, thf) were isolated by crystallization from diethyl ether. Single crystal X-ray diffraction studies revealed a heterometallic aggregate of composition [Li3Ln2Me9(thf)n(Et2O)m] with a [LiLn2Me9](2-) core (Ln = Sc, Y, Tb). When tris(tetramethylaluminate) [Ln(AlMe4)3] (Ln = Y, Lu) was reacted with less than 1 equiv of [NR3H][BPh4], the dimethyl cations [LnMe2(thf)n][BPh4] were obtained. The coordination number as well as cis/trans isomer preference was studied by crystallographic and computational methods. Dicationic methyl complexes of the rare-earth metals of the formula [LnMe(thf)n][BAr4]2 (Ln = Sc, Y, La-Nd, Sm, Gd-Lu; Ar = Ph, C6H4F-4) were synthesized, by protonolysis of either the ate complex [Li3LnMe6(thf)n] (Ln = Sc, Y, Gd-Lu) or the tris(tetramethylaluminate) [Ln(AlMe4)3] (Ln = La-Nd, Sm, Dy, Gd) with ammonium borates [NR3H][BAr4] in thf. The number of coordinated thf ligands varied from n = 5 (Ln = Sc, Tm) to n = 6 (Ln = La, Y, Sm, Dy, Ho). The configuration of representative examples was determined by X-ray diffraction studies and confirmed by density-functional theory calculations. The highly polarized bonding between the methyl group and the rare-earth metal center results in the reactivity pattern dominated by the carbanionic character and the pronounced Lewis acidity: The dicationic methyl complex [YMe(thf)6](2+) inserted benzophenone as an electrophile to give the alkoxy complex [Y(OCMePh2)(thf)5](2+). Nucleophilic addition of the soft anion X(-) (X(-) = I(-), BH4(-)) led to the monocationic methyl complexes [YMe(X)(thf)5](+).
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Affiliation(s)
- Mathias U Kramer
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, D-52074 Aachen, Germany
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Peckermann I, Robert D, Englert U, Spaniol TP, Okuda J. Neutral and Cationic Trimethylsilylmethyl Complexes of Indium. Organometallics 2008. [DOI: 10.1021/om800562z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ilja Peckermann
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, D-52074 Aachen, Germany
| | - Dominique Robert
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, D-52074 Aachen, Germany
| | - Ulli Englert
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, D-52074 Aachen, Germany
| | - Thomas P. Spaniol
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, D-52074 Aachen, Germany
| | - Jun Okuda
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, D-52074 Aachen, Germany
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Li S, Miao W, Tang T, Dong W, Zhang X, Cui D. New Rare Earth Metal Bis(alkyl)s Bearing an Iminophosphonamido Ligand. Synthesis and Catalysis toward Highly 3,4-Selective Polymerization of Isoprene. Organometallics 2008. [DOI: 10.1021/om700945r] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shihui Li
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Peopleʼs Republic of China, and Graduate School of the Chinese Academy of Sciences, Beijing 100039, Peopleʼs Republic of China
| | - Wei Miao
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Peopleʼs Republic of China, and Graduate School of the Chinese Academy of Sciences, Beijing 100039, Peopleʼs Republic of China
| | - Tao Tang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Peopleʼs Republic of China, and Graduate School of the Chinese Academy of Sciences, Beijing 100039, Peopleʼs Republic of China
| | - Weimin Dong
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Peopleʼs Republic of China, and Graduate School of the Chinese Academy of Sciences, Beijing 100039, Peopleʼs Republic of China
| | - Xuequan Zhang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Peopleʼs Republic of China, and Graduate School of the Chinese Academy of Sciences, Beijing 100039, Peopleʼs Republic of China
| | - Dongmei Cui
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Peopleʼs Republic of China, and Graduate School of the Chinese Academy of Sciences, Beijing 100039, Peopleʼs Republic of China
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Robert D, Kondracka M, Okuda J. Cationic rare-earth metal bis(tetrahydridoborato) complexes: direct synthesis, structure and ring-opening polymerisation activity toward cyclic esters. Dalton Trans 2008:2667-9. [DOI: 10.1039/b801030g] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Ly HV, Konu J, Parvez M, Roesler R. Tuning the electronic properties of cyclopentadienyl analogs with CB2N2 frameworks: 1,2-diphenyl-1,2-diaza-3,5-diborolyl ligands and their alkali metal salts. Dalton Trans 2008:3454-60. [DOI: 10.1039/b802930j] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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