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1. Alkene Oligomerization via metallacycles: Recent Advances and Mechanistic Insights

Author

Lionel Magna, Julien Petit, Nicolas Mézailles, Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), IFP Energies nouvelles (IFPEN), Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
chemistry.chemical_classification, Reaction mechanism, Ethylene, 010405 organic chemistry, Alkene, metallacycle, alkene, Metallacycle, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, Cyclobutane, oligomerization, Inorganic Chemistry, Butadiene Derivatives, chemistry.chemical_compound, chemistry, Computational chemistry, Mechanism (philosophy), Materials Chemistry, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Physical and Theoretical Chemistry
Abstract

International audience; The transformation of ethylene and alkenes is of high importance for the chemical industry. In this review, we focus on selective alkenes transformation where metallacyclopentane is suspected or demonstrated to be involved in the reaction mechanism. In addition to the alkenes, the "classical" products of ethylene oligomerization, we also cover articles dealing with the synthesis of cyclobutane and butadiene derivatives, through the common metallacycle intermediate. We also present studies that help decipher the precise mechanism of the transformations, i.e. involving synthesis of postulated intermediates, labelling experiments and DFT calculations.

Published
2022
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2. Synthesis of L2Ni(ORF)2 (RF=C(CF3)3) Complexes and their Reactivity in Ethylene Oligomerization

Author

Julien Petit, Nathalie Saffon-Merceron, Lionel Magna, Nicolas Mézailles, Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), IFP Energies nouvelles (IFPEN), and Université de Toulouse (UT)

Subjects
Inorganic Chemistry, Mathematical methods, Organic Chemistry, [SDE]Environmental Sciences, Precursors, [CHIM]Chemical Sciences, Selectivity, [CHIM.CATA]Chemical Sciences/Catalysis, Physical and Theoretical Chemistry, Ligands, Hydrocarbons
Abstract

International audience; A family of L2Ni(ORF)2 (L2: (Cy3PO)24, dcpmS 5, dppf 9, bipyMe210; RF = C(CF3)3) complexes is synthesized via selective substitution of 2 equiv of (DME)NaORF from homoleptic [Ni(ORF)4][Na(DME)]2 complex 1, all characterized by 19F and 1H NMR and SCXRD analyses as well as elemental analyses. These L2Ni(ORF)2 precursors, activated by 2 equiv of PhF → Al(ORF)3, were active in ethylene oligomerization with selectivity toward butenes up to 97% and activities ranging from 10 to 50 kgC2H4·gNi·h–1. Mechanistic investigations, involving experiments with C2H4/C2D4 (1/1) coupled with GC-MS analysis, revealed the formation of a Ni–H fragment in the catalytic process. The L2Ni(ORF)2/2PhF → Al(ORF)3 catalytic system thus dimerizes ethylene through a Cossee–Arlman mechanism.

Published
2021
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3. Cu-Catalyzed P–C bond formation/cleavage: straightforward synthesis/ring-expansion of strained cyclic phosphoniums

Author

Lionel Magna, György Szalóki, Maryne Duval, Didier Bourissou, Helene Olivier-Bourbigou, Sonia Mallet-Ladeira, E. Daiann Sosa Carrizo, Abderrahmane Amgoune, Karinne Miqueu, Damien Delcroix, Charlie Blons, Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), IFP Energies nouvelles (IFPEN), Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM), Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
010405 organic chemistry, Aryl, Phosphonium salt, chemistry.chemical_element, [CHIM.MATE]Chemical Sciences/Material chemistry, Crystal structure data n° 1998316 - RUVFOG sur CCDC, 010402 general chemistry, 01 natural sciences, Medicinal chemistry, Oxidative addition, Copper, Reductive elimination, 0104 chemical sciences, Inorganic Chemistry, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry.chemical_compound, [CHIM.POLY]Chemical Sciences/Polymers, chemistry, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Reactivity (chemistry), Phosphonium, Phosphine
Abstract

International audience; Upon reaction with copper(i), peri-halo naphthyl phosphines readily form peri-bridged naphthyl phosphonium salts. The reaction works with alkyl, aryl and amino substituents at phosphorus, with iodine, bromine and chlorine as a halogen. It proceeds under mild conditions and is quantitative, despite the strain associated with the resulting 4-membered ring structure and the naphthalene framework. The transformation is amenable to catalysis. Under optimized conditions, the peri-iodo naphthyl phosphine 1-I is converted into the corresponding peri-bridged naphthyl phosphonium salt 2b in only 5 minutes at room temperature using 1 mol% of CuI. Based on DFT calculations, the reaction is proposed to involve a Cu(i)/Cu(iii) cycle made of P-coordination, C-X oxidative addition and P-C reductive elimination. This copper-catalyzed route gives a general and efficient access to peri-bridged naphthyl phosphonium salts for the first time. Reactivity studies could thus be initiated and the possibility to insert gold into the strained P-C bond was demonstrated. It leads to (P,C)-cyclometallated gold(iii) complexes. According to experimental observations and DFT calculations, two mechanistic pathways are operating: (i) direct oxidative addition of the strained P-C bond to gold,(ii) backward-formation of the peri-halo naphthyl phosphine (by C-P oxidative addition to copper followed by C-X reductive elimination), copper to gold exchange and oxidative addition of the C-X bond to gold. Detailed analysis of the reaction profiles computed theoretically gives more insight into the influence of the nature of the solvent and halogen atom, and provides rationale for the very different behaviour of copper and gold in this chemistry.

Published
2020
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4. Nickel catalyzed olefin oligomerization and dimerization

Author

Damien Delcroix, Lionel Magna, Typhène Michel, M. Fernandez Espada Pastor, Helene Olivier-Bourbigou, Pierre-Alain Breuil, and IFP Energies nouvelles (IFPEN)

Subjects
Olefin fiber, Catalysts, 010405 organic chemistry, Chemistry, chemistry.chemical_element, General Chemistry, [CHIM.CATA]Chemical Sciences/Catalysis, 010402 general chemistry, Ligands, 01 natural sciences, Hydrocarbons, 0104 chemical sciences, Catalysis, Nickel, Petrochemical, Organic chemistry, Oligomerization, [CHIM]Chemical Sciences
Abstract

International audience; Brought to life more than half a century ago and successfully applied for high-value petrochemical intermediates production, nickel-catalyzed olefin oligomerization is still a very dynamic topic, with many fundamental questions to address and industrial challenges to overcome. The unique and versatile reactivity of nickel enables the oligomerization of ethylene, propylene and butenes into a wide range of oligomers that are highly sought-after in numerous fields to be controlled. Interestingly, both homogeneous and heterogeneous nickel catalysts have been scrutinized and employed to do this. This rare specificity encouraged us to interlink them in this review so as to open up opportunities for further catalyst development and innovation. An in-depth understanding of the reaction mechanisms in play is essential to being able to fine-tune the selectivity and achieve efficiency in the rational design of novel catalytic systems. This review thus provides a complete overview of the subject, compiling the main fundamental/industrial milestones and remaining challenges facing homogeneous/heterogeneous approaches as well as emerging catalytic concepts, with a focus on the last 10 years.

Published
2020
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5. Titanium-based phenoxy-imine catalyst for selective ethylene trimerization: effect of temperature on the activity, selectivity and properties of polymeric side products

Author

Lionel Magna, Typhène Michel, Helene Olivier-Bourbigou, Astrid Cordier, Pierre-Alain Breuil, Jean Raynaud, Christophe Boisson, Vincent Monteil, Université Claude Bernard Lyon 1 (UCBL), Université de Lyon, and IFP Energies nouvelles (IFPEN)

Subjects
Ethylene, 010405 organic chemistry, Comonomer, Dispersity, Side reaction, 010402 general chemistry, 01 natural sciences, Catalysis, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Polymerization, Polymer chemistry, [CHIM]Chemical Sciences, Reactivity (chemistry), Selectivity
Abstract

International audience; The reactivity of a phenoxy-imine-ether system (FI)TiCl3/MAO was studied toward selective ethylene trimerization. This system was shown to either trimerize or polymerize ethylene depending on the reaction temperature. Its selectivity switches from a significant production of the trimerization product, 1-hexene (85 wt %, 520-450 kg1-hexene gTi-1 h-1) between 30 and 40 °C, to a moderate polyethylene formation (70-80 wt %, 60-70 kgpolyethylene gTi-1 h-1) at higher reaction temperature (T > 60 °C). Polymerization was investigated based on an original "polymer-to-catalyst" strategy aiming at identifying the active species responsible for this side reaction. Using DSC, SEC and high temperature 13 C NMR analyses, polyethylenes were found to exhibit high molar masses (> 10 5 g mol-1) and a low 1-hexene content (< 1 mol %) at any temperature. Kinetic studies support that trimerization and polymerization species are generated from the catalyst precursor at 40 °C but a parallel process may occur at higher temperature. The increase dispersity to 4.6 at 80 °C suggests a change from single to multisite catalysis. The poor comonomer incorporation ability of the active species is reminiscent of a molecular Ziegler Natta or a bulky postmetallocene catalyst.

Published
2020
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6. Alternative aluminum-based cocatalysts for the iron-catalyzed oligomerization of ethylene

Author

Adrien Boudier, Pierre Braunstein, Pierre-Alain Breuil, Helene Olivier-Bourbigou, Lionel Magna, IFP Energies nouvelles (IFPEN), Institut de Chimie de Strasbourg, and Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
inorganic chemicals, In situ, Ethylene, Cocatalyst, Chemistry, Iron catalyzed, chemistry.chemical_element, [CHIM.CATA]Chemical Sciences/Catalysis, Ligands, Inorganic Chemistry, chemistry.chemical_compound, Alkylaluminium, Aluminium, Olefin polymerization, Organic chemistry, [CHIM]Chemical Sciences, Phenols, Polymerization catalysts
Abstract

International audience; Multinuclear aluminum cocatalysts have been obtained by the reaction of various phenols, alcohols or diois with trimethylaluminum and were used in situ or as isolated, welldefined species, for the activation of an iron(ll) or an iron(lll) precatalyst for the oligomerization of ethylene. The best cocatalyst candidate involves 2,2'-biphenol (10) in a 10/AIMe3 ratio of 2/3.

Published
2015
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7. Ethylene oligomerization using iron complexes : beyond the discovery of bis(imino)pyridine ligands

Author

Helene Olivier-Bourbigou, Lionel Magna, Pierre-Alain Breuil, Pierre Braunstein, Adrien Boudier, IFP Energies nouvelles (IFPEN), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Ethylene, Process development, Stereochemistry, Structural diversity, 010402 general chemistry, 01 natural sciences, Catalysis, chemistry.chemical_compound, Materials Chemistry, heterocyclic compounds, 010405 organic chemistry, Ligand, Chemistry, Metals and Alloys, General Chemistry, [CHIM.CATA]Chemical Sciences/Catalysis, Combinatorial chemistry, Pyridine ligand, 3. Good health, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Polymerization, Ceramics and Composites, Selectivity
Abstract

International audience; Since the discovery that bis(imino)pyridine ligands are able to confer high activities in ethylene oligomerization and polymerization to their iron complexes, considerable attention has been focused on catalyst design for these reactions and this research constitutes an ever-growing area in molecular catalysis. The tuning of the ligand structures and properties, and thus of catalysts, generally represents the basis for subsequent work contributing to process development and industrialization. Significant effort is therefore devoted to generate structural diversity in order to access the required catalyst stability and selectivity. This feature article outlines nitrogen-containing ligands that have been developed for the iron-catalyzed oligomerization of ethylene since the seminal discovery of the properties of bis(imino)pyridine ligands.

Published
2013
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