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1. Phenylacetylene and Carbon Dioxide Activation by an Organometallic Samarium Complex

Author

Violaine Goudy, Mathieu Xémard, Simon Karleskind, Marie Cordier, Carlos Alvarez Lamsfus, Laurent Maron, and Grégory Nocton

Subjects
small molecule activation, samarium complexes, C–H activation, Inorganic chemistry, QD146-197
Abstract

Small molecule activation is a topic of growing importance and the use of low-valent f-elements to perform these reactions is nowadays well established. The complex Cptt2Sm(thf) (1, Cptt = 1,3-(tBu)2Cp) is shown to activate the alkyne C–H bond of phenylacetylene to form the Cptt2Sm(C≡C–Ph)(thf) complex. The subsequent reaction of this Sm(III) complex with CO2 leads to the CO2 insertion, yielding a dimeric [Cptt2Sm(O2C–C≡C–Ph)]2 complex (2), in which the carbon dioxide has been inserted in the Sm–C bond. Along with the experimental chemical structure analysis, theoretical calculations have been performed in order to rationalize the formation of 1 and 2.

Published
2018
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2. Small molecule activation with divalent samarium triflate: a synergistic effort to cleave O2

Author

Elisa Louyriac, Grégory Nocton, Carine Clavaguéra, Mathieu Xémard, Laurent Maron, and Marie Cordier

Subjects
chemistry.chemical_classification, Lanthanide, 010405 organic chemistry, Salt (chemistry), chemistry.chemical_element, 010402 general chemistry, 01 natural sciences, Small molecule, 0104 chemical sciences, Divalent, Inorganic Chemistry, Samarium, Samarium triflate, chemistry, Cleave, Reductive cleavage, Polymer chemistry
Abstract

The divalent samarium triflate salt does not react with CO2 or water, but does react with traces of O2 or N2O to form a tetrameric bis-oxo samarium motif. The reaction with O2 is a 4e− reductive cleavage where the electrons are coming from four different samarium centers. This highlights a rare synergistic effect for cleaving O2, which has no precedent in divalent lanthanide complexes. Additionally, the addition of CO2 to the tetrameric bis-oxo intermediate leads to the formation of a tetrameric bis-carbonate samarium triflate. Thus, the concomitant reaction of CO2 with traces of O2 leads to the same bis-carbonate tetrameric assembly.

Published
2018
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3. Reductive Disproportionation of CO2 with Bulky Divalent Samarium Complexes

Author

Violaine Goudy, Augustin Braun, Grégory Nocton, Christos E. Kefalidis, Mathieu Xémard, Laurent Maron, Marie Cordier, Carine Clavaguéra, Elisa Louyriac, Louis Ricard, Maxime Tricoire, and Ludovic Castro

Subjects
chemistry.chemical_classification, 010405 organic chemistry, Dimer, Organic Chemistry, Inorganic chemistry, chemistry.chemical_element, Disproportionation, 010402 general chemistry, 01 natural sciences, Medicinal chemistry, 0104 chemical sciences, 3. Good health, Divalent, Adduct, Inorganic Chemistry, Samarium, Solvent, chemistry.chemical_compound, chemistry, Pyridine, Physical and Theoretical Chemistry, Diethyl ether
Abstract

The base-free divalent samarium complex Cptt2Sm (1; Cptt = 1,3-(tBu)2(C5H3)) has been synthesized in diethyl ether by salt metathesis of SmI2. Crystals of 1 suitable for X-ray study have been obtained by sublimation at 116 °C under reduced pressure. The dissolution of 1 in thf and pyridine solution leads to the solvent adducts Cptt2Sm(thf)2 (3) and Cptt2Sm(py) (4), respectively, while drying 3 under reduced pressure yields CpttSm(thf) (5). The reaction of CO2 with the base-free divalent samarium complexes Cptt2Sm (1) and Cpttt2Sm (2; Cpttt =1,2,4-(tBu)3(C5H2)) leads to the clean formation of bridged carbonate samarium dimers [Cpttt2Sm]2(μ-CO3) (7) and [Cptt2Sm]2(μ-CO3) (8). This is indicative of the reductive disproportionation of CO2 in both cases with release of CO. This contrasts with the formation of the oxalate-bridged samarium dimer reported from the reaction of CO2 with the Cp*2Sm(thf)2 complex. Otherwise, the reaction with CO does not proceed with the bulky complexes, while traces of O2 have led t...

Published
2017
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4. Divalent Thulium Crown Ether Complexes with Field-Induced Slow Magnetic Relaxation

Author

Grégory Nocton, Olivier Maury, Carole Duboc, Mathieu Xémard, Florian Molton, Olivier Cador, Boris Le Guennic, Marie Cordier, Laboratoire de chimie moléculaire (LCM), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X), Département de Chimie Moléculaire (DCM), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Laboratoire de Chimie - UMR5182 (LC), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), CNRS, Ecole polytechnique, IR-RPE CNRS FR3443 network, École polytechnique (X)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
chemistry.chemical_classification, Lanthanide, Spintronics, 010405 organic chemistry, Ligand, chemistry.chemical_element, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, 010402 general chemistry, 01 natural sciences, 3. Good health, 0104 chemical sciences, Coordination complex, law.invention, Inorganic Chemistry, Thulium, chemistry, Chemical physics, law, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Physical and Theoretical Chemistry, Ground state, Electron paramagnetic resonance, Crown ether
Abstract

International audience; The tailoring of the coordination chemistry around f-element centers is a crucial step for the development of compounds with slow magnetic relaxation, including single-molecule magnets (SMMs), which have great potential in molecular spintronics and for future quantum computing devices. Lanthanide ions are particularly interesting because the predominant electrostatic model of their bonding allows rationalizing their coordination symmetry. However, to the best of our knowledge, the redox properties of the lanthanides are not taken into account for the design of SMMs, and therefore all SMMs reported to date contain lanthanide ions in their trivalent oxidation state. In this Article, divalent lanthanide compounds presenting field-induced slow magnetic relaxation are reported. The rational design and synthesis of two TmII complexes with the 18-crown-6 ligand are presented along with their emission and EPR properties, which help to probe the desired nature of the ground state, that is, maximizing the anisotropy. The observed magnetic properties demonstrate their slow magnetic relaxation behavior in a moderate external magnetic field.

Published
2019
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5. Lanthanidocenes: Synthesis, Structure, and Bonding of Linear Sandwich Complexes of Lanthanides

Author

Carine Clavaguéra, Marie Cordier, Grégory Nocton, Sébastien Zimmer, Mathieu Xémard, Violaine Goudy, Louis Ricard, Laboratoire de chimie moléculaire (LCM), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X), Laboratoire de Chimie Physique D'Orsay (LCPO), and Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Lanthanide, 010405 organic chemistry, Ligand, Molecular orbital diagram, General Chemistry, 010402 general chemistry, 01 natural sciences, Biochemistry, Catalysis, 0104 chemical sciences, Crystallography, chemistry.chemical_compound, Colloid and Surface Chemistry, Uranocene, chemistry, Ferrocene, Isostructural, [CHIM.OTHE]Chemical Sciences/Other, Isomerization, Conformational isomerism, ComputingMilieux_MISCELLANEOUS
Abstract

The Article presents the synthesis, structure, and bonding of a series of neutral and linear sandwich compounds with the cyclononatetraenyl (Cnt) ligand and divalent lanthanides. These compounds account for the emergence of the lanthanidocene series in reference to the ferrocene and uranocene. The synthetic strategy uses the solubility difference between two conformational isomers of the ligand, as well as the isomerization of the compounds induced by solvent coordination, yielding the isomorphous and isostructural neutral and rigorously linear sandwich complexes. The molecular structures feature a Cnt–Ln–Cnt angle of 180° and a ring size close to the Cnt–Cnt(centroid) distance. A qualitative molecular orbital diagram is provided, in D9d symmetry, and DFT calculations enforce the bonding model.

Published
2018

6. Phenylacetylene and Carbon Dioxide Activation by an Organometallic Samarium Complex

Author

Carlos Alvarez Lamsfus, Simon Karleskind, Violaine Goudy, Grégory Nocton, Mathieu Xémard, Laurent Maron, Marie Cordier, Laboratoire de chimie moléculaire (LCM), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-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 du CNRS (INC), École polytechnique (X)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-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)-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 sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
chemistry.chemical_classification, small molecule activation, 010405 organic chemistry, Chemical structure, Alkyne, chemistry.chemical_element, 010402 general chemistry, 01 natural sciences, Small molecule, lcsh:QD146-197, 3. Good health, 0104 chemical sciences, Inorganic Chemistry, Samarium, chemistry.chemical_compound, Phenylacetylene, chemistry, Carbon dioxide, Polymer chemistry, lcsh:Inorganic chemistry, samarium complexes, C–H activation, C-H activation, [CHIM.OTHE]Chemical Sciences/Other
Abstract

Small molecule activation is a topic of growing importance and the use of low-valent f-elements to perform these reactions is nowadays well established. The complex Cptt2Sm(thf) (1, Cptt = 1,3-(tBu)2Cp) is shown to activate the alkyne C&ndash, H bond of phenylacetylene to form the Cptt2Sm(C&equiv, C&ndash, Ph)(thf) complex. The subsequent reaction of this Sm(III) complex with CO2 leads to the CO2 insertion, yielding a dimeric [Cptt2Sm(O2C&ndash, C&equiv, Ph)]2 complex (2), in which the carbon dioxide has been inserted in the Sm-C bond. Along with the experimental chemical structure analysis, theoretical calculations have been performed in order to rationalize the formation of 1 and 2.

Published
2018
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7. Small molecule activation with divalent samarium triflate: a synergistic effort to cleave O

Author

Mathieu, Xémard, Marie, Cordier, Elisa, Louyriac, Laurent, Maron, Carine, Clavaguéra, and Grégory, Nocton

Abstract

The divalent samarium triflate salt does not react with CO2 or water, but does react with traces of O2 or N2O to form a tetrameric bis-oxo samarium motif. The reaction with O2 is a 4e- reductive cleavage where the electrons are coming from four different samarium centers. This highlights a rare synergistic effect for cleaving O2, which has no precedent in divalent lanthanide complexes. Additionally, the addition of CO2 to the tetrameric bis-oxo intermediate leads to the formation of a tetrameric bis-carbonate samarium triflate. Thus, the concomitant reaction of CO2 with traces of O2 leads to the same bis-carbonate tetrameric assembly.

Published
2018

8. Back Cover: Divalent Thulium Triflate: A Structural and Spectroscopic Study (Angew. Chem. Int. Ed. 15/2017)

Author

Marie Cordier, Florian Molton, Olivier Maury, Carole Duboc, Carine Clavaguéra, Grégory Nocton, Olivier Cador, Arnaud Jaoul, Boris Le Guennic, Mathieu Xémard, Laboratoire de chimie moléculaire (LCM), École polytechnique (X)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Département de Chimie Moléculaire - Chimie Inorganique Redox Biomimétique (DCM - CIRE ), Département de Chimie Moléculaire (DCM), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Polytechnique de Bordeaux-Université de Bordeaux (UB), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie - UMR5182 (LC), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), Laboratoire de Chimie Physique D'Orsay (LCPO), Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Département de Chimie Moléculaire - Chimie Inorganique Redox (DCM - CIRE ), Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)

Subjects
chemistry.chemical_classification, Lanthanide, 010405 organic chemistry, Inorganic chemistry, chemistry.chemical_element, General Chemistry, 01 natural sciences, Catalysis, 0104 chemical sciences, Divalent, law.invention, Thulium, chemistry, law, Polymer chemistry, [CHIM]Chemical Sciences, Cover (algebra), Electron paramagnetic resonance, Trifluoromethanesulfonate, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2017
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10. Multiple One-Electron Transfers in Bipyridine Complexes of Bis(phospholyl) Thulium

Author

Léa Jacquot, Grégory Nocton, Mathieu Xémard, Carine Clavaguéra, Tard, Cédric, Laboratoire de chimie moléculaire (LCM), and Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)

Subjects
010405 organic chemistry, Ligand, Organic Chemistry, chemistry.chemical_element, Electron, 010402 general chemistry, Photochemistry, 01 natural sciences, Redox, Divalent metal, 0104 chemical sciences, Ion, Inorganic Chemistry, Bipyridine, chemistry.chemical_compound, Electron transfer, Crystallography, Thulium, chemistry, [CHIM.OTHE] Chemical Sciences/Other, Physical and Theoretical Chemistry, [CHIM.OTHE]Chemical Sciences/Other, ComputingMilieux_MISCELLANEOUS
Abstract

The synthesis of original neutral bis(phospholyl) thulium complexes, Dtp2Tm(L), where L is tetramethylbiphosphinine (tmbp) and bipyridine (bipy), is reported. The electronic structures of these complexes have been investigated and it appears that, in both cases, an electron transfer occurs from the divalent metal to the ligand, a consequence of the strong reduction potential of the bis(phospholyl) thulium fragment, Dtp2Tm. When 1 equiv of bipyridine is added to the Dtp2Tm(tmbp) complex, another electron transfer occurs to form the Dtp2Tm(bipy) complex along with free tmbp ligand. Astonishingly, despite the apparent trivalent nature of the thulium center, the Dtp2Tm(bipy) complex is still reactive toward neutral bipyridine to form a new complex in which one phospholyl ligand is replaced by a bipyridine radical anion. An experimental kinetic analysis is reported to rationalize this unprecedented redox reaction with thulium and reveals an associative type of mechanism.

Published
2014

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