Author: "Laurent Maron" / Topic: general chemistry - Searchworks@Jio Institute Digital Library Search Results

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293 results on '"Laurent Maron"'

1. Isolation of C1 through C4 derivatives from CO using heteroleptic uranium(<scp>iii</scp>) metallocene aryloxide complexes

Author: Robert J. Ward, Iker del Rosal, Steven P. Kelley, Laurent Maron, and Justin R. Walensky
Subjects: General Chemistry
Abstract: Functionalization of CO from C1 to C4 is acheived using a heteroleptic uranium(iii) complex.
Published: 2023
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2. A versatile strategy for the formation of hydride-bridged actinide–iridium multimetallics

Author: Christopher Z. Ye, Iker Del Rosal, Michael A. Boreen, Erik T. Ouellette, Dominic R. Russo, Laurent Maron, John Arnold, and Clément Camp
Subjects: General Chemistry
Abstract: Uranium- and thorium-iridium multimetallic species with unprecedented actinide–iridium interactions are prepared via salt-elimination reactions between U/Th halides and K[IrCp*H3].
Published: 2023
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3. Molybdenum carbonyl assisted reductive tetramerization of CO by activated magnesium(<scp>i</scp>) compounds: squarate dianion vs. metallo-ketene formation

Author: K. Yuvaraj, Jeremy C. Mullins, Thayalan Rajeshkumar, Iskander Douair, Laurent Maron, and Cameron Jones
Subjects: General Chemistry
Abstract: The reductive tetramerisation of CO by Lewis base activated dimagnesium(i) compounds, in the presence of Mo(CO)6, led to the competitive formation of magnesium squarate and metallo-ketene complexes (see picture).
Published: 2023
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4. Unusual selective reactivity of the rare-earth metal complexes bearing a ligand with multiple functionalities

Author: Dongjing Hong, Thayalan Rajeshkumar, Shan Zhu, Zeming Huang, Shuangliu Zhou, Xiancui Zhu, Laurent Maron, Shaowu Wang, Anhui Normal University, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and Anhui Polytechnic University
Subjects: indole, Fischer-type carbene, rare-earth metal complexes, [CHIM]Chemical Sciences, dianionic 3-iminoindolyl, General Chemistry, N-heterocyclic carbene, 1-migratory insertion
Abstract: International audience; Ligands play a key role in controlling activity of organometallic complexes so that development of new ligands to overcome the challenge is the main topic of modern chemistry. The first example of 1,1-hydride migratory insertion and intramolecular redox reaction has been realized in this work by applying a new ligand in rare-earth metal chemistry. The novel rare-earth metal complexes LMesRECH2TMS(THF) (RE = Y (1a), Dy (1b), Er (1c), Yb (1d), LMes = 1-(3-(2,6-iPr2C6H3N=CH)C8H4N)-CH2CH2-3-(2-CH2—4,6-Me2C6H2)-(N(CH)2NC), THF = tetrahydrofuran) bearing a ligand with imino, indolyl, NHC (N-heterocyclic carbene) multiple functionalities were synthesized and characterized. Treatment of complexes 1 with silanes (PhSiH3 or PhSiH2Me or PhSiD3) selectively produced the unprecedented 1,1-hydride (or deuterated H) migratory insertion of the indolyl moiety of the novel unsymmetrical dinuclear rare-earth metal complexes 2. The complex 2a reacts with Ph2C-O to give the selective C-O double bond insertion to the RE-Co-methylene-Mes bond product 3a which further reacts with another Ph2C-O (or DMAP, 4-N, N-dimethylaminopyridine) affording the novel μ-η2:η3-dianionic 3-iminoindolyl dinuclear rare-earth metal complex 4a. The latter is formed through an unusual intramolecular redox reaction (through electron migration from the 2-carbanion of the indolyl ring to the imino motif) resulting in the re-aromatization of the indolyl ring.
Published: 2022
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5. Mechanistic Investigations on Bismuth Catalyzed Reduction of Ketones and Phosphine Oxides

Author: Annabel Benny, Deepti Sharma, Ankur ., Thayalan Rajeshkumar, Laurent Maron, and Ajay Venugopal
Subjects: Organic Chemistry, General Chemistry, Catalysis
Published: 2023
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6. A Route to Stabilize Uranium(II) and Uranium(I) Synthons in Multimetallic Complexes

Author: R. A. Keerthi Shivaraam, Megan Keener, Dieuwertje K. Modder, Thayalan Rajeshkumar, Ivica Živković, Rosario Scopelliti, Laurent Maron, and Marinella Mazzanti
Subjects: General Medicine, General Chemistry, Catalysis
Abstract: Herein, we report the redox reactivity of a multimetallic uranium complex supported by triphenylsiloxide (−OSiPh3) ligands, where we show that low valent synthons can be stabilized via an unprecedented mechanism involving intramolecular ligand migration. The two- and three-electron reduction of the oxo-bridged diuranium(IV) complex [{(Ph3SiO)3(DME)U}2(μ-O)], 4, yields the formal “UII/UIV”, 5, and “UI/UIV”, 6, complexes via ligand migration and formation of uranium-arene δ-bond interactions. Remarkably, complex 5 effects the two-electron reductive coupling of pyridine affording complex 7, which demonstrates that the electron-transfer is accompanied by ligand migration, restoring the original ligand arrangement found in 4. This work provides a new method for controlling the redox reactivity in molecular complexes of unstable, low-valent metal centers, and can lead to the further development of f-elements redox reactivity.
Published: 2023
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7. Magnesium(I) Reduction of Aluminum(III) Hydride Complexes: Generation of Mixed Valence Aluminum (AlI/Al0) Hydride Cluster Compounds, [Al6H8(NR3)2{Mg(-diketiminate)}4]

Author: Sneha Mullassery, K. Yuvaraj, Deepak Dange, Dafydd Jones, Iker del Rosal, Ross Piltz, Alison Edwards, Laurent Maron, and Cameron Jones
Subjects: General Chemistry, General Medicine, Catalysis
Abstract: Reduction of a range of amido- and aryloxy-aluminum dihydride complexes, e.g. [AlH2(NR3){N(SiMe3)2}] (NR3 = NMe3 or N-methylpiperidine (NMP)), with -diketiminato dimagnesium(I) reagents, [{(ArNacnac)Mg}2] (ArNacnac = [HC(MeCNAr)2]-, Ar = mesityl (Mes) or 2,6-xylyl (Xyl)), have afforded deep red mixed valence aluminum hydride cluster compounds, [Al6H8(NR3)2{Mg(ArNacnac)}4], which have an average Al oxidation state of +0.66, the lowest for any well-defined aluminum hydride compound. In the solid-state, the clusters are shown to have distorted octahedral Al6 cores, having zero-valent Al axial sites and mono-valent AlH2- equatorial units. Several novel by-products were isolated from the reactions that gave the clusters, including the Mg‒Al bonded magnesio-aluminate complexes, [(ArNacnac)(Me3N)Mg‒Al(-H)3[{Mg(ArNacnac)}2(-H)]]. Computational analyses of one aluminum hydride cluster revealed its Al6 core to be electronically delocalized, and to possess one unoccupied, and six occupied, skeletal molecular orbitals.
Published: 2023
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8. Reductive activation of N2 using a calcium/potassium bimetallic system supported by an extremely bulky diamide ligand

Author: Rahul Mondal, K. Yuvaraj, Thayalan Rajeshkumar, Laurent Maron, Cameron Jones, School of Chemistry, Monash University, 3800 Clayton, Victoria (Australie), Monash University [Clayton], Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: spectroscopy, Materials Chemistry, Metals and Alloys, Ceramics and Composites, [CHIM]Chemical Sciences, General Chemistry, nitrogen, Catalysis, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials
Abstract: An extremely bulky xanthene bridged diamide ligand ((NON)-N-TCHP = 4,5-bis(2,4,6-tricyclohexylanilido)-2,7-diethyl-9,9-dimethyl-xanthene) has been developed and used to prepare two monomeric diamido-calcium complexes [((NON)-N-TCHP)Ca(D)(n)] (D = THF, n = 2, 3; D = toluene, n = 1, 4). Reduction of 4 with 5% w/w K/KI under an N-2 atmosphere gave the first well-defined, hetero-bimetallic s-block complex of activated dinitrogen, [{K((NON)-N-TCHP)Ca}(2)(mu-eta(2):eta(2)-N-2)] 5, presumably via a transient calcium(i) intermediate.
Published: 2022
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9. Electronic structure studies reveal 4f/5d mixing and its effect on bonding characteristics in Ce-imido and -oxo complexes

Author: Liane M. Moreau, Ekaterina Lapsheva, Jorge I. Amaro-Estrada, Michael R. Gau, Patrick J. Carroll, Brian C. Manor, Yusen Qiao, Qiaomu Yang, Wayne W. Lukens, Dimosthenis Sokaras, Eric J. Schelter, Laurent Maron, Corwin H. Booth, Lawrence Berkeley National Laboratory, Chemical Sciences Division, Lawrence, Department of Chemistry, The Pennsylvania State University, Pennsylvania State University (Penn State), Penn State System-Penn State System, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Stanford Synchrotron Radiation Lightsource (SSRL SLAC), SLAC National Accelerator Laboratory (SLAC), Stanford University-Stanford University, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences, Quantum Information Systems Program of the U.S. Department of Energy (DOE) at LBNL [DE-AC02-05CH11231], National Science Foundation [CHE1955724], Office of Basic Energy Sciences, Chemical Sciences, Geosciences and Biosciences Division, Materials and Chemical Sciences Research for Quantum Information Science Program, of the U.S. Department of Energy [DE-SC0020169], and University of Pennsylvania
Subjects: Chemical Sciences, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], General Chemistry
Abstract: This study presents the role of 5d orbitals in the bonding, and electronic and magnetic structure of Ce imido and oxo complexes synthesized with a tris(hydroxylaminato) [((2- t BuNO)C6H4CH2)3N]3- (TriNO x 3-) ligand framework, including the reported synthesis and characterization of two new alkali metal-capped Ce oxo species. X-ray spectroscopy measurements reveal that the imido and oxo materials exhibit an intermediate valent ground state of the Ce, displaying hallmark features in the Ce LIII absorption of partial f-orbital occupancy that are relatively constant for all measured compounds. These spectra feature a double peak consistent with other formal Ce(iv) compounds. Magnetic susceptibility measurements reveal enhanced levels of temperature-independent paramagnetism (TIP). In contrast to systems with direct bonding to an aromatic ligand, no clear correlation between the level of TIP and f-orbital occupancy is observed. CASSCF calculations defy a conventional van Vleck explanation of the TIP, indicating a single-reference ground state with no low-lying triplet excited state, despite accurately predicting the measured values of f-orbital occupancy. The calculations do, however, predict strong 4f/5d hybridization. In fact, within these complexes, despite having similar f-orbital occupancies and therefore levels of 4f/5d hybridization, the d-state distributions vary depending on the bonding motif (Ce[double bond, length as m-dash]O vs. Ce[double bond, length as m-dash]N) of the complex, and can also be fine-tuned based on varying alkali metal cation capping species. This system therefore provides a platform for understanding the characteristic nature of Ce multiple bonds and potential impact that the associated d-state distribution may have on resulting reactivity.
Published: 2022
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10. Bonding and Reactivity in Terminal versus Bridging Arenide Complexes of Thorium Acting as Th II Synthons

Author: Fang‐Che Hsueh, Thayalan Rajeshkumar, Bastiaan Kooij, Rosario Scopelliti, Kay Severin, Laurent Maron, Ivica Zivkovic, and Marinella Mazzanti
Subjects: General Chemistry, General Medicine, Catalysis
Abstract: Thorium redox chemistry is extremely scarce due to the high stability of Th(IV). Here we report two unique examples of thorium arenide complexes prepared by reduction of a Th(IV)-siloxide complex in presence of naphthalene, the mononuclear arenide complex [K(OSi(OtBu)3)3Th(η6-C10H8)] (1) and the inverse-sandwich complex [K(OSi(OtBu)3)3Th]2(μ-η6,η6-C10H8)] (2). The electrons stored in these complexes allow the reduction of a broad range of substrates (N2O, AdN3, CO2, HBBN). Higher reactivity was found for the complex 1 which reacts with the diazoolefin IDipp=CN2 to yield the unexpected Th(IV) amidoalkynyl complex 5via a terminal N-heterocyclic vinylidene intermediate. This work showed that arenides can act as convenient redox-active ligands for implementing thorium-ligand cooperative multielectron transfer and that the reactivity can be tuned by the arenide binding mode.
Published: 2023
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11. Isolation and redox reactivity of cerium complexes in four redox states

Author: Fang-Che Hsueh, Thayalan Rajeshkumar, Laurent Maron, Rosario Scopelliti, Andrzej Sienkiewicz, and Marinella Mazzanti
Subjects: metal, reductive disproportionation, ions, series, c-h activation, General Chemistry, carbon-dioxide, chemistry, ligand, lanthanide(iii), crystal-structures
Abstract: The chemistry of lanthanides is limited to one electron transfer reactions due to the difficulty of accessing multiple oxidation states. Here we report that a redox-active ligand combining three siloxides with an arene ring in a tripodal ligand can stabilize cerium complexes in four different redox states and can promote multielectron redox reactivity in cerium complexes. Ce(iii) and Ce(iv) complexes [(LO3)Ce(THF)] (1) and [(LO3)CeCl] (2) (LO3 = 1,3,5-(2-OSi((OBu)-Bu-t)(2)C6H4)(3)C6H3) were synthesized and fully characterized. Remarkably the one-electron reduction and the unprecedented two-electron reduction of the tripodal Ce(iii) complex are easily achieved to yield reduced complexes [K(2.2.2-cryptand)][(LO3)Ce(THF)] (3) and [K-2{(LO3)Ce(Et2O)(3)}] (5) that are formally "Ce(ii)" and "Ce(i)" analogues. Structural analysis, UV and EPR spectroscopy and computational studies indicate that in 3 the cerium oxidation state is in between +II and +III with a partially reduced arene. In 5 the arene is doubly reduced, but the removal of potassium results in a redistribution of electrons on the metal. The electrons in both 3 and 5 are stored onto d-bonds allowing the reduced complexes to be described as masked "Ce(ii)" and "Ce(i)". Preliminary reactivity studies show that these complexes act as masked Ce(ii) and Ce(i) in redox reactions with oxidizing substrates such as Ag+, CO2, I-2 and S-8 effecting both one- and two-electron transfers that are not accessible in classical cerium chemistry.
Published: 2023
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12. Facile Synthesis of Uranium Complexes with a Pendant Borane Lewis Acid and 1,2‐Insertion of CO into a U−N Bond

Author: Wei Su, Thayalan Rajeshkumar, Libo Xiang, Laurent Maron, Qing Ye, Anhui Polytechnic University, Southern University of Science and Technology (SUSTech), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and Julius-Maximilians-Universität Würzburg (JMU)
Subjects: Carbon Monoxide, ddc:540, Uranium, [CHIM]Chemical Sciences, General Medicine, General Chemistry, Boranes, Catalysis, Boron, Lewis Acids
Abstract: In this contribution, we illustrate uranium complexes bearing a pendant borate (i.e. 1 and 2) or a pendant borane (i.e. 3 and 4) moiety via reaction of the highly strained uranacycle I with various 3-coordinate boranes. Complexes 3 and 4 represent the first examples of uranium complexes with a pendant borane Lewis acid. Moreover, complex 3 was capable of activation of CO, delivering a new CO activation mode, and an abnormal CO 1,2-insertion pathway into a U-N bond. The importance of the pendant borane moiety was confirmed by the controlled experiments.
Published: 2022
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13. Elemental chalcogen reactions of a tetravalent uranium imidophosphorane complex: cleavage of dioxygen

Author: Luis M. Aguirre Quintana, Thayalan Rajeshkumar, Ningxin Jiang, Julie E. Niklas, John Bacsa, Laurent Maron, Henry S. La Pierre, School of Chemistry and Biochemistry [Atlanta], Georgia Institute of Technology [Atlanta], Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and George W. Woodruff School of Mechanical Engineering
Subjects: Organoimido, Reactivity, Metals and Alloys, Activation, General Chemistry, Catalysis, Atom-transfer, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Oxygen, Materials Chemistry, Ceramics and Composites, Uranyl-ion, [CHIM]Chemical Sciences, Uranium, Chalcogens, Sulfur, SE, Analogs
Abstract: Herein we report the first example of a mononuclear uranium complex, [U4+(NP(pip)3)4] (1-U), that selectively reduces dioxygen to produce a terminal oxo complex, [U6+O(NP(pip)3)4] (2-U; [NP(pip)3]1− is tris(piperidinyl)imidophosphorane). Reactions between 1-U and the heavier elemental chalcogens, S8 or Se0, result in six-coordinate U(VI) complexes, [U6+(κ2-E3)(NP(pip)3)4] (E = S (3-U) or Se (4-U)).
Published: 2022
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14. Reversible Oxidative Addition of Zinc Hydride at a Gallium(I)‐Centre: Labile Mono‐ and Bis(hydridogallyl)zinc Complexes

Author: Louis J. Morris, Thayalan Rajeshkumar, Laurent Maron, Jun Okuda, Institute of Inorganic Chemistry [Aachen] (IAC RWTH), Rheinisch-Westfälische Technische Hochschule Aachen University (RWTH), Chemistry Research Laboratory [Oxford, UK], University of Oxford, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: gallium, ddc:540, Organic Chemistry, zinc, hydrides, [CHIM]Chemical Sciences, General Chemistry, heterometallic complexes, Catalysis
Abstract: Chemistry - a European journal 28(56), e202201480 (2022). doi:10.1002/chem.202201480, Published by Wiley-VCH, Weinheim
Published: 2022
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15. Assembling diuranium complexes in different states of charge with a bridging redox-active ligand

Author: Dieuwertje K. Modder, Mikhail S. Batov, Thayalan Rajeshkumar, Andrzej Sienkiewicz, Ivica Zivkovic, Rosario Scopelliti, Laurent Maron, Marinella Mazzanti, Institut des Sciences et Ingénierie Chimiques (ISIC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratory for Quantum Magnetism, and ADS resonances Sàrl
Subjects: SINGLE-MOLECULE-MAGNET, ELECTRONIC-STRUCTURE, DILANTHANIDE COMPLEXES, OXO COMPLEXES, [CHIM]Chemical Sciences, U-IV-E, General Chemistry, GROUND-STATES, EXCHANGE, URANIUM(III) COMPLEX, COORDINATION-COMPLEXES, LANTHANIDE(III)/ACTINIDE(III) DIFFERENTIATION
Abstract: Radical-bridged diuranium complexes are desirable for their potential high exchange coupling and single molecule magnet (SMM) behavior, but remain rare. Here we report for the first time radical-bridged diuranium(IV) and diuranium(III) complexes. Reaction of [U{N(SiMe3)(2)}(3)] with 2,2'-bipyrimidine (bpym) resulted in the formation of the bpym-bridged diuranium(IV) complex [{((Me3Si)(2)N)(3)U-}2(IV)(mu-bpym(2-))], 1. Reduction with 1 equiv. KC8 reduces the complex, affording [K(2.2.2-cryptand)][{((Me3Si)(2)N)(3)U)(2)(mu-bpym)], 2, which is best described as a radical-bridged UIII-bpym center dot-U-III complex. Further reduction of 1 with 2 equiv. KC8, affords [K(2.2.2-cryptand)](2)[{((Me3Si)(2)N)(3)U-III}(2)(mu-bpym(2-))], 3. Addition of AgBPh4 to complex 1 resulted in the oxidation of the ligand, yielding the radical-bridged complex [{((Me3Si)(2)N)(3)U-IV}(2)(mu-bpym center dot-)][BPh4], 4. X-ray crystallography, electrochemistry, susceptibility data, EPR and DFT/CASSCF calculations are in line with their assignments. In complexes 2 and 4 the presence of the radical-bridge leads to slow magnetic relaxation.
Published: 2022
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16. The mechanism of Fe induced bond stability of uranyl( v )

Author: Tonya Vitova, Radmila Faizova, Jorge I. Amaro-Estrada, Laurent Maron, Tim Pruessmann, Thomas Neill, Aaron Beck, Bianca Schacherl, Farzaneh Fadaei Tirani, Marinella Mazzanti, Karlsruhe Institute of Technology (KIT), Institut des Sciences et Ingénierie Chimiques (ISIC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: COVALENCY, Technology, General Chemistry, SERIES, ELECTRONIC-STRUCTURE, REDUCTION, CHEMISTRY, U(VI), WYARTITE, FUNCTIONALIZATION, [CHIM]Chemical Sciences, COMPLEXES, ION, ddc:600
Abstract: The stabilization of uranyl(v) (UO21+) by Fe(ii) in natural systems remains an open question in uranium chemistry. Stabilization of UVO21+ by Fe(ii) against disproportionation was also demonstrated in molecular complexes. However, the relation between the Fe(ii) induced stability and the change of the bonding properties have not been elucidated up to date. We demonstrate that U(v) - oaxial bond covalency decreases upon binding to Fe(ii) inducing redirection of electron density from the U(v) - oaxial bond towards the U(v) - equatorial bonds thereby increasing bond covalency. Our results indicate that such increased covalent interaction of U(v) with the equatorial ligands resulting from iron binding lead to higher stability of uranyl(v). For the first time a combination of U M4,5 high energy resolution X-ray absorption near edge structure (HR-XANES) and valence band resonant inelastic X-ray scattering (VB-RIXS) and ab initio multireference CASSCF and DFT based computations were applied to establish the electronic structure of iron-bound uranyl(v).
Published: 2022
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17. A Planar Nickelaspiropentane Complex with Magnesium-Based Metalloligands: Synthesis, Structure, and Synergistic Dihydrogen Activation

Author: Yanping Cai, Shengjie Jiang, Thayalan Rajeshkumar, Laurent Maron, Xin Xu, Soochow University, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Colloid and Surface Chemistry, Catalysts, Mathematical methods, Nickel, [CHIM]Chemical Sciences, General Chemistry, Catalytic reactions, Biochemistry, Catalysis, Hydrocarbons
Abstract: The nature of transition-metal–olefin bonding has been explained by the Dewar–Chatt–Duncanson model within a continuum of two extremes, namely, a π-complex and a metallacyclopropane. The textbook rule suggests that a low-spin late-transition-metal–ethylene complex more likely forms a π-complex rather than a metallacyclopropane. Herein, we report a low-spin late-transition-metal–bis-ethylene complex forming an unprecedented planar metalla-bis-cyclopropane structure with magnesium-based metalloligands. Treatment of LMgEt (L = [(DippNCMe)2CH]−, Dipp = 2,6-iPr2C6H3) with Ni(cod)2 (cod = 1,5-cyclooctadiene) formed the heterotrimetallic complex (LMg)2Ni(C2H4)2, which features a linear Mg–Ni–Mg linkage and a planar coordination geometry at the nickel center. Both structural features and computational studies strongly supported the Ni(C2H4)2 moiety as a nickelaspiropentane. The exposure of (LMg)2Ni(C2H4)2 to 1 bar H2 at room temperature produced a four-hydride-bridged complex (LMg)2Ni(μ-H)4. The profile of H2 activation was elucidated by density functional theory calculations, which indicated a novel Mg/Ni cooperative activation mechanism with no oxidation occurring at the metal center, differing from the prevailing mono-metal-based redox mechanism. Moreover, the heterotrimetallic complex (LMg)2Ni(C2H4)2 catalyzed the hydrogenation of a wide range of unsaturated substrates under mild conditions.
Published: 2022
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18. Spontaneous Ammonia Activation Through Coordination‐Induced Bond Weakening in Molybdenum Complexes of a Dianionic Pentadentate Ligand Platform

Author: C. Christopher Almquist, Nicole Removski, Thayalan Rajeshkumar, Benjamin S. Gelfand, Laurent Maron, Warren E. Piers, Department of Chemistry, University of Calgary, University of Calgary, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Molybdenum, Ligand Design, [CHIM]Chemical Sciences, Density Functional Calculations, General Medicine, General Chemistry, Bond Activation, Ammonia Oxidation, Catalysis
Abstract: Ammonia oxidation catalyzed by molecular compounds is of current interest as a carbon-free source of dihydrogen. Activation of N-H bonds through coordination to transition metal centers is a key reaction in this process. We report the substantial activation of ammonia via reaction with low-valent molybdenum complexes of a diborate pentadentate ligand system. Spontaneous loss of dihydrogen from (B
Published: 2022
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19. Uranium(III)–Phosphorus(III) Synergistic Activation of White Phosphorus and Arsenic

Author: Shuao Wang, Wei Fang, Peter W. Roesky, Congqing Zhu, Iskander Douair, Laurent Maron, Kai Li, Adrian Hauser, Yue Zhao, Nanjing University (NJU), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Karlsruhe Institute of Technology (KIT), and Soochow University
Subjects: chemistry, Transition metal, White Phosphorus, Environmental chemistry, Phosphorus, chemistry.chemical_element, [CHIM]Chemical Sciences, General Chemistry, Uranium, Arsenic
Abstract: The study of small-molecule activation by f-block elements still lags far behind that of transition metals. Although a few uranium complexes have been reported to activate dinitrogen, reports on th...
Published: 2022
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20. Ytterbium (II) Hydride as a Powerful Multielectron Reductant

Author: Iskander Douair, Scott A. Cameron, Laurent Maron, Mathew D. Anker, Georgia M. Richardson, Victoria University of Wellington, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Ytterbium, polyaromatic hydrocarbons, Hydrogen, Hydride, multielectron reduction, Organic Chemistry, naphthalene, Aromatization, chemistry.chemical_element, General Chemistry, Photochemistry, Catalysis, chemistry.chemical_compound, 7-cyclooctatetraene, Deprotonation, chemistry, ytterbium hydrides, Density functional theory, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Naphthalene
Abstract: International audience; A dimeric beta-diketiminato ytterbium(II) hydride affects both the two-electron aromatization of 1,3,5,7-cyclooctatetraene (COT) and the more challenging two-electron reduction of polyaromatic hydrocarbons, including naphthalene (E-0=-2.60 V). Confirmed by Density Functional Theory calculations, these reactions proceed via consecutive polarized Yb-H/C=C insertion and deprotonation steps to provide the respective ytterbium (II) inverse sandwich complexes and hydrogen gas. These observations highlight the ability of a simple ytterbium(II) hydride to act as a powerful two-electron reductant at room temperature without the necessity of an external electron to initiate the reaction and avoiding radicaloid intermediates.
Published: 2021
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21. Organocalcium Complex-Catalyzed Selective Redistribution of ArSiH3 or Ar(alkyl)SiH2 to Ar3SiH or Ar2(alkyl)SiH

Author: Karl N. McCabe, Laurent Maron, Yaofeng Chen, Xuebing Leng, Tao Li, Beijing Academy of Science and Technology, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), National Natural Science Foundation of China [21732007, 21890721, 21821002], K. C. Wong Education Foundation, Strategic Priority Research Program of the Chinese Academy of Sciences [XDB20000000], Shanghai Municipal Committee of Science and Technology, Program of Shanghai Academic Research Leader, and Chinese Academy of Sciences President's International Fellowship Initiative
Subjects: chemistry.chemical_classification, calcium, Chemistry, hydrosilane, Redistribution (chemistry), [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], General Chemistry, Photochemistry, DFT, Catalysis, Alkyl, redistribution
Abstract: International audience; Calcium is an abundant, biocompatible, and environmentally friendly element. The use of organocalcium complexes as catalysts in organic synthesis has had some breakthroughs recently, but the reported reaction types remain limited. On the other hand, hydrosilanes are highly important reagents in organic and polymer syntheses, and redistribution of hydrosilanes through C-Si and SiH bond cleavage and reformation provides a straightforward strategy to diversify the scope of such compounds. Herein, we report the synthesis and structural characterization of two calcium alkyl complexes supported by beta-diketiminato-based tetradentate ligands. These two calcium alkyl complexes react with PhSiH3 to generate calcium hydrido complexes, and the stability of the hydrido complexes depends on the supporting ligands. One calcium alkyl complex efficiently catalyzes the selective redistribution of ArSiH3 or Ar(alkyl)SiH2 to Ar3SiH and SiH4 or Ar-2(alkyl)SiH and alkylSiH(3), respectively. More significantly, this calcium alkyl complex also catalyzes the cross-coupling between the electron-withdrawing substituted Ar(R)SiH2 and the electron-donating substituted Ar'(R)SiH2, producing ArAr'(alkyl)SiH in good yields. The synthesized ArAr'(alkyl)SiH can be readily transferred to other organosilicon compounds such as ArAr'(alkyl)SiX (where X = OH, OEt, NEt2, and CH2SiMe3). DFT investigations are carried out to shed light on the mechanistic aspects of the redistribution of Ph(Me)SiH2 to Ph-2(Me)SiH and reveal the low activation barriers (17-19 kcal/mol) in the catalytic reaction.
Published: 2021
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22. Heterometallic Clusters with Multiple Rare Earth Metal–Transition Metal Bonding

Author: Penglong Wang, Yue Zhao, Kaiying Shi, Iskander Douair, Genfeng Feng, Congqing Zhu, Laurent Maron, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Nanjing Normal Univ, Key Lab Virtual Geog Environm, Minist Educ, Nanjing 210023, Peoples R China, National Natural Science Foundation of China [21772088, 91961116], Natural Science Foundation of Jiangsu Province [BK20200302], Fundamental Research Funds for the Central Universities [14380216], and Programs for high-level entrepreneurial and innovative talents introduction of Jiangsu Province (group program)
Subjects: Magnetism, Chemistry, Molecular cluster, Rare earth, General Chemistry, 010402 general chemistry, 01 natural sciences, Biochemistry, Catalysis, 0104 chemical sciences, Metal, Crystallography, Colloid and Surface Chemistry, Transition metal, X-ray photoelectron spectroscopy, Oxidation state, visual_art, visual_art.visual_art_medium, Molecule, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]
Abstract: International audience; Although a series of complexes with rare earth (RE) metal-metal bonds have been reported, complexes which have multiple RE-Rh bonds are unknown. Here we present the identification of the first example of a molecule containing multiple RE-Rh bonds. The complex with multiple Ce-Rh bonds was synthesized by the reduction of a d-f heterometallic molecular cluster Ce{N[((CH2CH2NPPr2)-Pr-i)RhCl(COD)](3)} with excess potassium-graphite. The oxidation state of Ce in 3a appears to be a mixture of Ce(III) and Ce(IV), which was confirmed by X-ray photoelectron spectroscopy, magnetism, and theoretical investigations (DFT and CASSCF). For comparison, the analogous species with multiple La(III)-Rh and Nd(III)-Rh bonds were also constructed. This study provides a possible route for the construction of complexes with multiple RE metal-metal bonds and an investigation of their potential properties and applications.
Published: 2021
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23. Insights into Rare-Earth Metal Complex-Mediated Hydroamination

Author: Kening Qiao, Jian Fang, Laurent Maron, Shuqi Dong, Yan Yang, Bo Liu, Jinjin Chen, Shanghai Institute of Materia Medica - Chinese Academy of Sciences [Shanghai], College of Civil Engineering and Mechanics, Xiangtan Univ., Xiangtan, Hunan 411105, China, Lanzhou Univ, Coll Civil Engn & Mech, Lanzhou, Peoples R China, Lanzhou University, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), University of Science and Technology of China [Hefei] (USTC), and NSF China [51673184]
Subjects: 010405 organic chemistry, Chemistry, Rare earth, Rational design, rare-earth metal complexes, stepwise s-insertive mechanism, DFT calculation, General Chemistry, 010402 general chemistry, 01 natural sciences, Combinatorial chemistry, Catalysis, 0104 chemical sciences, hydroamination, Metal, kinetic study, visual_art, visual_art.visual_art_medium, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Hydroamination, Mechanism (sociology)
Abstract: International audience; Since the precise understanding of the underlying mechanism is important for the rational design of catalysts, much attention has been paid for hydroamination reactions catalyzed by organolanthanides during the past three decades. Distinct mechanisms were proposed on the basis of some key experimental features. It is a challenge to distinguish these mechanisms. The present study focuses on this controversial topic by synthesizing an almost entire range of rare-earth metal bisalkyl complexes (Py-CH2-Flu)Ln(CH2SiMe3)(2)(THF)(x) (Ln = Sc (1), Lu (2), Tm (3), Er (4), Ho (5), Y (6), Dy (7), Tb (8), Gd (9), and Pr (10)) stablized by a pyridine methylene fluorenyl ligand to catalyze intramolecular hydroamination (IAHA) of prototypical 1-amino-2,2-diphenyl-4-pentene and intermolecular hydroamination (IEHA) of styrene and pyrrolidine. Among them, thulium-, terbium-, and gadolinium-based catalysts were investigated for the first time. As observed for all the reported catalytic systems, the rate of IAHA increased almost linearly with increasing metal ion radius, whereas the reactivity pattern in IEHA with respect to the ionic radius size follows the opposite trend. Kinetic studies were carried out to obtain the empirical rate law v = k[Ln](1.0)[S](0.0) for IAHA and v = k[Ln](1.0)[St](1.0)[pyrrolidine](0.0) for IEHA. The zero-order dependence on amine was attributed to the population ratio between the rare-earth metal amido adduct and its precursor being larger than 10(4). Density functional theory studies on scandium, yttrium, and praseodymium complex-mediated IAHA and IEHA were investigated using a stepwise sigma-insertive mechanism and a concerted noninsertive mechanism, respectively. The results suggested the prevailing mechanism to be a stepwise sigma-insertive pathway that involves the insertion of C=C into the Ln-N bond and protonolysis of the Ln-C bond. The protonolysis reaction is the turnover-limiting step. The reason behind the influence of the metal ion radius on the catalytic activity was elucidated.
Published: 2021
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24. Computational Insights into Different Mechanisms for Ag‐, Cu‐, and Pd‐Catalyzed Cyclopropanation of Alkenes and Sulfonyl Hydrazones

Author: Laurent Maron, Yong Wu, Iskander Douair, Shanshan Cao, Xihe Bi, Northeast Normal University, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), NSFC [21871043, 21961130376], Department of Science and Technology of Jilin Province [20180101185JC, 20190701012GH], and Fundamental Research Funds for the Central Universities [2412020FZ006]
Subjects: Sulfonyl, chemistry.chemical_classification, 010405 organic chemistry, Cyclopropanation, Alkene, Organic Chemistry, General Chemistry, 010402 general chemistry, 01 natural sciences, Combinatorial chemistry, Catalysis, Cycloaddition, 0104 chemical sciences, Cyclopropane, carbenes, reaction mechanisms, chemistry.chemical_compound, chemistry, density functional calculations, hindered alkenes, silver, Diazo, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Carbene
Abstract: International audience; The [2+1] cycloaddition reaction of a metal carbene with an alkene can produce important cyclopropane products for synthetic intermediates, materials, and pharmaceutical applications. However, this reaction is often accompanied by side reactions, such as coupling and self-coupling, so that the yield of the cyclopropanation product of non-silver transition-metal carbenes and hindered alkenes is generally lower than 50 %. To solve this problem, the addition of a low concentration of diazo compound (decomposition of sulfonyl hydrazones) to alkenes catalyzed by either CuOAc or PdCl2 was studied, but side reactions could still not be avoided. Interestingly, however, the yield of cyclopropanation products for such hindered alkenes were as high as 99 % with AgOTf as a catalyst. To explain this unexpected phenomenon, reaction pathways have been computed for four different catalysts by using DFT. By combining the results of these calculations with those obtained experimentally, it can be concluded that the efficiency of the silver catalyst is due to the barrierless concerted cycloaddition step and the kinetic inhibition of side reactions by a high concentration of alkene.
Published: 2021
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25. Photochemically Activated Dimagnesium(I) Compounds: Reagents for the Reduction and Selective C−H Bond Activation of Inert Arenes

Author: Laurent Maron, Cameron Jones, Iskander Douair, Dafydd D. L. Jones, Monash Univ, Dept. mat. Engn, Monash University [Clayton], Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Australian Research Council, Humboldt Foundation, and Chinese Academy of Science
Subjects: chemistry.chemical_classification, photochemistry, arene reduction, Radical, Fluorobenzene, Xylene, Regioselectivity, NacNac, General Chemistry, General Medicine, DFT calculations, Medicinal chemistry, Toluene, Cand#8722, Catalysis, chemistry.chemical_compound, chemistry, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Bridged compounds, Benzene, magnesium(I), H activation
Abstract: International audience; The photochemical activation of dimagnesium(I) compounds, and subsequent high yielding, regioselective reactions with inert arenes are reported. Irradiating benzene solutions of [{((Ar)Nacnac)Mg}(2)] ((Ar)Nacnac=[HC(MeCNAr)(2)](-); Ar=2,6-diisopropylphenyl (Dip) or 2,4,6-tricyclohexylphenyl (TCHP)) with blue or UV light, leads to double reduction of benzene and formation of the "Birch-like" cyclohexadienediyl bridged compounds, [{((Ar)Nacnac)Mg}(2)(mu-C6H6)]. Irradiation of [{((Dip)Nacnac)Mg}(2)] in toluene, and each of the three isomers of xylene, promoted completely regio- and chemo-selective C-H bond activations, and formation of [((Dip)Nacnac)Mg(Ar ')] (Ar '=meta-tolyl; 2,3-, 3,5- or 2,5-dimethylphenyl), and [{((Dip)Nacnac)Mg(mu-H)}(2)]. Fluorobenzene was cleanly defluorinated by photoactivated [{((Dip)Nacnac)Mg}(2)], leading to biphenyl and [{((Dip)Nacnac)Mg(mu-F)}(2)]. Computational studies suggest all reactions proceed via photochemically generated magnesium(I) radicals, which reduce the arene substrate, before C-H or C-F bond activation processes occur.
Published: 2021
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26. Scandium-Terminal Boronylphosphinidene Complex

Author: Laurent Maron, Xuebing Leng, Yaofeng Chen, Bin Feng, Li Xiang, Ambre Carpentier, University of Chinese Academy of Sciences [Beijing] (UCAS), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), National Natural Science Foundation of China [21732007, 21890721, 21821002], K. C. Wong Education Foundation, Strategic Priority Research Program of the Chinese Academy of Sciences [XDB20000000], Shanghai Municipal Committee of Science and Technology, Program of Shanghai Academic Research Leader, and Chinese Academy of Sciences President's International Fellowship Initiative
Subjects: chemistry.chemical_element, General Chemistry, Weak interaction, 010402 general chemistry, 01 natural sciences, Biochemistry, Catalysis, 0104 chemical sciences, Bond length, Crystallography, Colloid and Surface Chemistry, chemistry, Nucleophile, Phosphinidene, Reactivity (chemistry), [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Scandium
Abstract: International audience; The first isolation and structural characterization of a rare-earth metal-terminal imido complex were reported in 2010, but a rare-earth metal-terminal phosphinidene complex is still absent, to date. Herein, we report the synthesis and structure of the first example of a rare-earth-terminal phosphinidene complex, namely the scandium boronylphosphinidene complex. Single-crystal X-ray diffraction shows that the complex has a much shorter Sc-P bond length as compared to that in a related scandium boronylphosphido complex, 2.381(1) angstrom vs 2.564(1) angstrom. DFT calculations indicate the presence of a strong Sc-P pi interaction in this complex, which is in striking contrast to the weak interaction found in the phosphido complex. A preliminary reactivity study demonstrates that the scandium-terminal boronylphosphinidene complex behaves as a nucleophilic phosphinidene complex.
Published: 2021
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27. Photochemical Synthesis of Transition Metal-Stabilized Uranium(VI) Nitride Complexes

Author: Xiaoqing Xin, Iskander Douair, Thayalan Rajeshkumar, Yue Zhao, Shuao Wang, Laurent Maron, Congqing Zhu, Nanjing University (NJU), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and Soochow University
Subjects: Multidisciplinary, MAGNETIC COMMUNICATION, AZIDE, CLEAVAGE, H BOND ACTIVATION, General Physics and Astronomy, TRANSIENT, General Chemistry, REACTIVITY, General Biochemistry, Genetics and Molecular Biology, REDUCTION, CHEMISTRY, FUNCTIONALIZATION, [CHIM]Chemical Sciences, PHOTOLYSIS
Abstract: Uranium nitrides play important roles in dinitrogen activation and functionalization and in chemistry for nuclear fuels, but the synthesis and isolation of the highly reactive uranium(VI) nitrides remains challenging. Here, we report an example of transition metal (TM) stabilized U(VI) nitride complexes, which are generated by the photolysis of azide-bridged U(IV)-TM (TM = Rh, Ir) precursors. The U(V) nitride intermediates with bridged azide ligands are isolated successfully by careful control of the irradiation time, suggesting that the photolysis of azide-bridged U(IV)-TM precursors is a stepwise process. The presence of two U(VI) nitrides stabilized by three TMs is clearly demonstrated by an X-ray crystallographic study. These TM stabilized U(V) nitride intermediates and U(VI) nitride products exhibit excellent stability both in the solid-state and in THF solution under ambient light. Density functional theory calculations show that the photolysis necessary to break the N-N bond of the azide ligands implies excitation from uranium f-orbital to the lowest unoccupied molecular orbital (LUMO), as suggested by the strong antibonding N-(N2) character present in the latter.
Published: 2022
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28. Redox-induced reversible P–P coupling in a uranium complex

Author: Xiong Sun, Laurent Maron, Yue Zhao, Wei Fang, Congqing Zhu, Ambre Carpentier, Nanjing Normal Univ, Key Lab Virtual Geog Environm, Minist Educ, Nanjing 210023, Peoples R China, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), National Natural Science Foundation of China [21772088, 91961116], Programs for high-level entrepreneurial and innovative talents introduction of Jiangsu Province, Humboldt Foundation, and Chinese Academy of Science
Subjects: Denticity, Ligand, Metals and Alloys, chemistry.chemical_element, General Chemistry, Uranium, Redox, Catalysis, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Coupling (electronics), Crystallography, chemistry, Materials Chemistry, Ceramics and Composites, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]
Abstract: International audience; A synthesized redox-active multidentate N-P ligand reacted with UCl4 in the presence of KHMDS or (BuLi)-Bu-n, where two novel U(iv) complexes with or without P-P coupling were formed, respectively. The reversible P-P coupling in these complexes was observed in redox-induced reactions.
Published: 2021
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29. Activation of ammonia and hydrazine by electron rich Fe(<scp>ii</scp>) complexes supported by a dianionic pentadentate ligand platform through a common terminal Fe(<scp>iii</scp>) amido intermediate

Author: Warren E. Piers, Michael L. Neidig, Benjamin S. Gelfand, Peter G. N. Neate, Lucie Nurdin, Yan Yang, Laurent Maron, Jian-Bin Lin, Department of Chemistry, University of Calgary, University of Calgary, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), University of Rochester [USA], Department of Chemical and Petroleum Engineering [Calgary], Natural Sciences and Engineering Research Council of Canada, French CNRS PICS project, Alberta Innovates Technology Futures, Vanier Canada Graduate Scholarships, Chinese Scholarship Council (CSC), and National Institutes of Health [R01GM111480]
Subjects: Hydrogen, 010405 organic chemistry, Ligand, Dimer, Hydrazine, chemistry.chemical_element, General Chemistry, 010402 general chemistry, 01 natural sciences, Redox, 3. Good health, 0104 chemical sciences, Adduct, Chemistry, Ammonia, chemistry.chemical_compound, chemistry, Transition metal, Polymer chemistry, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]
Abstract: We report the use of electron rich iron complexes supported by a dianionic diborate pentadentate ligand system, B2Pz4Py, for the coordination and activation of ammonia (NH3) and hydrazine (NH2NH2). For ammonia, coordination to neutral (B2Pz4Py)Fe(ii) or cationic [(B2Pz4Py)Fe(iii)]+ platforms leads to well characterized ammine complexes from which hydrogen atoms or protons can be removed to generate, fleetingly, a proposed (B2Pz4Py)Fe(iii)–NH2 complex (3Ar-NH2). DFT computations suggest a high degree of spin density on the amido ligand, giving it significant aminyl radical character. It rapidly traps the H atom abstracting agent 2,4,6-tri-tert-butylphenoxy radical (ArO˙) to form a C–N bond in a fully characterized product (2Ar), or scavenges hydrogen atoms to return to the ammonia complex (B2Pz4Py)Fe(ii)–NH3 (1Ar-NH3). Interestingly, when (B2Pz4Py)Fe(ii) is reacted with NH2NH2, a hydrazine bridged dimer, (B2Pz4Py)Fe(ii)–NH2NH2–Fe(ii)(B2Pz4Py) ((1Ar)2-NH2NH2), is observed at −78 °C and converts to a fully characterized bridging diazene complex, 4Ar, along with ammonia adduct 1Ar-NH3 as it is allowed to warm to room temperature. Experimental and computational evidence is presented to suggest that (B2Pz4Py)Fe(ii) induces reductive cleavage of the N–N bond in hydrazine to produce the Fe(iii)–NH2 complex 3Ar-NH2, which abstracts H˙ atoms from (1Ar)2-NH2NH2 to generate the observed products. All of these transformations are relevant to proposed steps in the ammonia oxidation reaction, an important process for the use of nitrogen-based fuels enabled by abundant first row transition metals., Synopsis: a highly reactive Fe(iii)–NH2 complex is generated via activation of ammonia or hydrazine in reactions of relevance to fundamental steps in ammonia oxidation processes mediated by an abundant, first row transition metal.
Published: 2021
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30. Accessing the +IV Oxidation State in Molecular Complexes of Praseodymium

Author: Farzaneh Fadaei-Tirani, Laurent Maron, Aurélien R. Willauer, Marinella Mazzanti, Ivica Zivkovic, Chad T. Palumbo, Iskander Douair, Ecole Polytechnique Fédérale de Lausanne (EPFL), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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: Lanthanide, lanthanide, Praseodymium, chemistry.chemical_element, Terbium, Ate complex, chemistry, 010402 general chemistry, 01 natural sciences, Biochemistry, Catalysis, law.invention, electron-paramagnetic-resonance, Colloid and Surface Chemistry, nitrate, law, Oxidation state, Electron paramagnetic resonance, General Chemistry, 0104 chemical sciences, yttrium, Crystallography, Cerium, ions, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Cyclic voltammetry
Abstract: Out of the 14 lanthanide (Ln) ions, molecular complexes of Ln(IV) were known only for cerium and more recently terbium. Here we demonstrate that the +IV oxidation state is also accessible for the large praseodymium (Pr) cation. The oxidation of the tetrakis(triphenysiloxide) Pr(III) ate complex, [KPr(OSiPh3)(4)(THF)(3)], 1-Pr-Ph, with [N(C6H4Br)(3)][SbCl6], affords the Pr(IV) complex [Pr(OSiPh3)(4)(MeCN)(2)], 2-Pr-Ph, which is stable once isolated. The solid state structure, UV-visible spectroscopy, magnetometry, and cyclic voltammetry data along with the DFT computations of the 2-Pr-Ph complex unambiguously confirm the presence of Pr(IV).
Published: 2020
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31. Synthesis, Characterization, and Reactivity of a Hydrido‐ and Imido‐Bridged Dinuclear Ytterbium(III) Complex

Author: Qingqing Wen, Thayalan Rajeshkumar, Laurent Maron, Xuebing Leng, Yaofeng Chen, University of Chinese Academy of Sciences [Beijing] (UCAS), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), National Natural Science Foundation of China [21732007, 21890721, 22071013], K.C. Wong Education Foundation, Shanghai Municipal Committee of Science and Technology, and Chinese Academy of Sciences President's International Fellowship Initiative
Subjects: Imido Ligands, Dinuclear Complexes, Oxidative Addition, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], General Chemistry, General Medicine, Ytterbium, Catalysis, Hydride Ligands
Abstract: International audience; The trivalent rare-earth metal hydrido and imido complexes are of versatile reactivity, and many such complexes have been synthesized. However, no example of a rare-earth metal complex bearing both hydrido- and imido-ligands has been reported. Herein, we report the first rare-earth metal complex bearing both hydrido- and imido-ligands, namely a hydrido- and imido-bridged dinuclear ytterbium(III) complex. The complex was synthesized via an unprecedented redox reaction of divalent rare-earth metal hydrido complex with azido compound. DFT calculation indicated that the N-2 release from azido compound in the presence of ytterbium(II) is a kinetically facile process because of the cooperative effects of the two metal centers. The reactivity of the hydrido- and imido-bridged dinuclear ytterbium(III) complex was also explored, which showed the redox, addition and sigma-bond metathesis reactivities.
Published: 2022
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32. Synthesis of Molecular Phenylcalcium Derivatives: Application to the Formation of Biaryls

Author: Kyle G. Pearce, Chiara Dinoi, Michael S. Hill, Mary F. Mahon, Laurent Maron, Ryan S. Schwamm, Andrew S. S. Wilson, University of Bath [Bath], Bath Spa University, Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), EPSRC [EP/R020752/1], and Royal Commission for the Exhibition of 1851
Subjects: Biaryls, Calcium, General Chemistry, Aryl Bromides, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], General Medicine, Main Group Chemistry, Catalysis, Density Functional Theory
Abstract: International audience; Hydrocarbon-soluble beta-diketiminato phenylcalcium derivatives, which display various modes of Ca-mu(2)-Ph-Ca bridging, are accessible from reactions of Ph2Hg and [(BDI)CaH](2). Although the resultant compounds are inert toward the C-H bonds of benzene, they yield selective and uncatalyzed biaryl formation when reacted with readily available aryl bromides.
Published: 2022
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33. A Masked Form of an O‐Borylated Breslow Intermediate for the Diastereoselective FLP‐Type Activation of Aldehydes

Author: Angelica Mejia Fajardo, Nicolas Queyriaux, Aurèle Camy, Laure Vendier, Mary Grellier, Iker del Rosal, Laurent Maron, Sébastien Bontemps, Laboratoire de chimie de coordination (LCC), 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), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), CNRS, and ANR-17-CE07-0015,ICC,Cycle de Calvin Inorganic(2017)
Subjects: FLP activation, Diastereoselective activation, Organic Chemistry, Breslow intermediates, CO2, [CHIM.COOR]Chemical Sciences/Coordination chemistry, General Chemistry, Boranes, Catalysis
Abstract: International audience; Breslow intermediates are very often elusive species whose application in frustrated Lewis pair (FLP) chemistry is unprecedented. Described herein is the use of a masked form of an O-borylated Breslow (OBB) intermediate that performs FLP-type activation of the carbonyl function of five different benzaldehyde derivatives with complete diastereoselectivity. The resulting compounds are characterised in solution by NMR spectroscopy (compounds 4–8) and in solid state by X-ray diffraction analysis (compounds 4–6). A combined kinetic and theoretical investigation reveals the associative nature of the rate determining step and suggests that the OBB intermediate part is never released during the whole process.
Published: 2022
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34. Reactivity of Multimetallic Thorium Nitrides Generated by Reduction of Thorium Azides

Author: Fang-Che Hsueh, Luciano Barluzzi, Megan Keener, Thayalan Rajeshkumar, Laurent Maron, Rosario Scopelliti, Marinella Mazzanti, Ecole Polytechnique Fédérale de Lausanne (EPFL), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Swiss National Science Foundation [178793], and Ecole Polytechnique Federale de Lausanne (EPFL)
Subjects: Colloid and Surface Chemistry, General Chemistry, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Biochemistry, Catalysis
Abstract: International audience; Thorium nitrides are likely intermediates in the reported cleavage and functionalization of dinitrogen by molecular thorium complexes and are attractive compounds for the study of multiple bond formation in f-element chemistry, but only one example of thorium nitride isolable from solution was reported. Here, we show that stable multimetallic azide/nitride thorium complexes can be generated by reduction of thorium azide precursors.a route that has failed so far to produce Th nitrides. Once isolated, the thorium azide/nitride clusters, M3Th = N = Th (M = K or Cs), are stable in solutions probably due to the presence of alkali ions capping the nitride, but their synthesis requires a careful control of the reaction conditions (solvent, temperature, nature of precursor, and alkali ion). The nature of the cation plays an important role in generating a nitride product and results in large structural differences with a bent Th = N = Th moiety found in the K-bound nitride as a result of a strong K-nitride interaction and a linear arrangement in the Cs-bound nitride. Reactivity studies demonstrated the ability of Th nitrides to cleave CO in ambient conditions yielding CN-.
Published: 2022
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35. Activation of CO Using a 1,2-Disilylene: Facile Synthesis of an Abnormal N-Heterocyclic Silylene

Author: Palak Garg, Ambre Carpentier, Iskander Douair, Deepak Dange, Yixiao Jiang, K. Yuvaraj, Laurent Maron, Cameron Jones, School of Chemistry, Monash University [Clayton], Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Bis(Silylene), Carbon Monoxide, Small Molecule Activation, 1,2-Disilylene, Abnormal N-Heterocyclic Carbenes, [CHIM]Chemical Sciences, General Medicine, General Chemistry, Catalysis
Abstract: Reaction of the 1,2-disilylene, {ArC(NDip)(2)}Si](2) 1 (Dip = 2,6-diisopropylphenyl, Ar =4-C6H4But), with CO proceeds via insertion of CO into one Si-N bond, and Si-Si bond cleavage, to cleanly give the bis(silylene), {ArC(NDip)(2)}Si(:)O Ar 2, tinder ambient conditions. The reaction can be partially reversed when solutions of 2 are subjected to UV irradiation. The five-membered heterocyclic fragment of 2 represents the first silicon analogue of an "abnormal" N-heterocyclic carbene (aNHC), a view which is substantiated by a computational analysis of the compound. Reaction of 2 with [Mo(CO)(6)] under UV light affords the chelate complex, [Mo(CO)(4)(kappa(2)-Si,Si-2)] 3, while reaction with [Fe(CO)(5)] gives the unusual silyleneyl bridged complex, [(Fe-2(CO)(6))(mu-Si[(NDip)(2)CAr]}(2)] 4. The same coordination complexes can be accessed by reaction of 1 with [Mo(CO)(6)] or [Fe(CO)(5)] under UV light. As is the case for aNHCs, d-block metal complexes of bis(silylene) 2 could prove useful as bespoke catalysts for organic transformations.
Published: 2022
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36. Selective hydroboration of terminal alkynes catalyzed by heterometallic clusters with uranium metal triple bonds

Author: Penglong Wang, Iskander Douair, Yue Zhao, Rile Ge, Junhu Wang, Shuao Wang, Laurent Maron, Congqing Zhu, Nanjing Normal Univ, Key Lab Virtual Geog Environm, Minist Educ, Nanjing 210023, Peoples R China, Centre National de la Recherche Scientifique (CNRS), INSA Institut National des Sciences Appliquées Hauts-de-France (INSA Hauts-De-France), Institut National des Sciences Appliquées (INSA), Shanghai Institute of Materia Medica - Chinese Academy of Sciences [Shanghai], Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), National Natural Science Foundation of China [91961116], Fundamental Research Funds for the Central Universities [14380262], programs for high-level entrepreneurial and innovative talents introduction of Jiangsu Province, Humboldt Foundation, and Chinese Academy of Science
Subjects: General Chemical Engineering, Biochemistry (medical), Materials Chemistry, Environmental Chemistry, General Chemistry, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Biochemistry
Abstract: International audience; Due to their fascinating structures and heterometallic synergistic effects in catalysis, heterometallic clusters with metal-metal (M-M) bonds have attracted the interest of chemists for decades. However, understanding of the chemistry of M-M bonds that involve f-block elements, such as uranium, is significantly less developed compared with that of the d-block transition metals, and catalysis by heterometallic clusters with U-M bonds has not been realized to date. Here, we report a set of heterometallic clusters that feature U M (M = Fe, Co) triple bonds. The cluster with two U Co triple bonds exhibits excellent catalytic activity for the hydroboration of alkynes under mild conditions, producing alpha-vinylboronates with good yields and regioselectivity. These heterometallic clusters represent the rare structurally authenticated example of multiple bonding between f-block elements and transition metals. Theoretical studies reveal high bond orders (up to 2.93) and a significant degree of covalency in these U M triple bonds.
Published: 2022
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37. A Brønsted Acidic Gallium Hydride: Facile Interconversion of NNNN‐Macrocycle Supported [Ga$^{I}$] + and [Ga$^{III}$H]$^{2+}$

Author: Louis J. Morris, Priyabrata Ghana, Thayalan Rajeshkumar, Ambre Carpentier, Laurent Maron, Jun Okuda, Institute of Inorganic Chemistry [Aachen] (IAC RWTH), Rheinisch-Westfälische Technische Hochschule Aachen University (RWTH), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Deutsche Forschungsgemeinschaft, Alexander von Humboldt Foundation, and Projekt DEAL
Subjects: [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Group 13 Elements, Redox Chemistry, Cations, Hydrides, ddc:540, Macrocyclic Ligands, [CHIM.COOR]Chemical Sciences/Coordination chemistry, General Chemistry, Catalysis
Abstract: International audience; Protonolysis of [Cp*M] (M=Ga, In, Tl) with [(Me(4)TACD)H][BAr4Me] (Me(4)TACD=N,N ',N '',N '''-tetramethyl-1,4,7,10-tetraazacyclododecane; [BAr4Me](-)=[B{C6H3-3,5-(CH3)(2)}(4)](-)) provided monovalent salts [(Me(4)TACD)M][BAr4Me], whereas [Cp*Al](4) yielded trivalent [(Me(4)TACD)AlH][BAr4Me](2). Protonation of [(Me(4)TACD)Ga][BAr4Me] with [Et3NH][BAr4Me] gave an unusually acidic (pK(a)(CH3CN)=24.5) gallium(III) hydride dication [(Me(4)TACD)GaH][BAr4Me](2). Deprotonation with IMe4 (1,3,4,5-tetramethyl-imidazol-ylidene) returned [(Me(4)TACD)Ga][BAr4Me]. These reversible processes occur with formal two-electron oxidation and reduction of gallium. DFT calculations suggest that gallium(I) protonation is facilitated by strong coordination of the tetradentate ligand, which raises the HOMO energy. High nuclear charge of [(Me(4)TACD)GaH](2+) facilitates hydride-to-metal charge transfer during deprotonation. Attempts to prepare a gallium(III) dihydride cation resulted in spontaneous dehydrogenation to [(Me(4)TACD)Ga](+).
Published: 2022
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38. Heterometallic Clusters with Uranium-Metal Bonds Supported by Double-Layer Nitrogen-Phosphorus Ligands

Author: Qin Zhu, Wei Fang, Laurent Maron, Congqing Zhu, Nanjing Normal Univ, Key Lab Virtual Geog Environm, Minist Educ, Nanjing 210023, Peoples R China, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), National Natural Science Foundation of China [21772088, 91961116], and Fundamental Research Funds for the Central Universities
Subjects: General Medicine, General Chemistry, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]
Abstract: International audience; CONSPECTUS: Heterometallic clusters with M-M bonds have significantly interested chemists because of their attractive structures and synergistic effects in small-molecule activation and catalysis. However, reports of the isolation of heterometallic clusters with uranium-transition metal (U-TM) bonds remain very limited. In this Account, we describe our research in the construction of heterometallic molecular clusters with multiple U-TM single or multiple bonds supported by novel double-layer N-P ligands. Multimetallic synergistic catalysis and small-molecule activation with these species are also summarized. First, according to the hard-soft acid-base theory, we employed a three-armed N-P ligand, which can be used to construct heterometallic clusters with four or six U-Ni bonds. This strategy was also effective in the construction of complexes with direct rare earth metal-TM bonding. The similar two-armed N-P ligands also are effective platforms for the synthesis of heterometallic complexes with U-Ni, U-Pd, and U-Pt bonds. Second, a set of heterometallic clusters featuring U Rh, U Co, and U Fe triple bonds were constructed under routine experimental conditions. X-ray diffraction analysis of these clusters exhibits the shortest U-TM bond distance (1.9693(4) angstrom for the U Fe triple bond) in these complexes. Theoretical studies reveal that the nature of the triple bond is one covalent sigma bond and two TM -> U dative pi bonds. A large Wiberg bond index (WBI) of 2.93 and a significant degree of covalency for the U TM triple bonds were also found in these complexes. Third, these uranium complexes supported by the double-layer N-P ligands exhibit great potential in small-molecule activation. For instance, N-2 cleavage without an external reducing agent was achieved by a U(III)-P(III) synergistic six-electron reduction. The synergism between U(III) and P(III) enables the activation of other small molecules, such as O-2, P-4, and As-(nano)(0), and highlights the importance of the P atom in the double-layer N-P ligand for the activation of small molecules. A heterometallic cluster with U-Rh bonds can break the strong N N triple bond in N-2 in the presence of potassium graphite, suggesting a synergistic effect between U and Rh. This multimetallic synergistic effect was also observed in catalytic processes. A heterometallic cluster with U Co triple bonds shows excellent selectivity and activity in the hydroboration of a series of alkynes under mild conditions. These results lead to effective methods for the construction of heterometallic molecular clusters with U-TM single or multiple bonds and could promote the application of heterometallic clusters with U-TM bonds in catalysis and the activation of small molecules.
Published: 2022
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39. CO, CO2 and CS2 activation by divalent ytterbium hydrido complexes

Author: Xianghui Shi, Thayalan Rajeshkumar, Laurent Maron, Jianhua Cheng, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), National Natural Science Foundation of China [21901238, 21971232], and HPCs CALcul en Midi-Pyrenees (CALMIP-EOS grant) [1415]
Subjects: Materials Chemistry, Metals and Alloys, Ceramics and Composites, General Chemistry, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Catalysis, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials
Abstract: International audience; Treatment of a divalent ytterbium hydride complex [(Tp(Ad,iPr))-Yb(H)(THF)] (Tp(Ad,iPr) = hydrotris(3-adamantyl-5-isopropyl-pyrazolyl)borate) (1) with CO, CO2 and CS2 resulted in the formation of a divalent ytterbium ethenediolate complex [(Tp(Ad,iPr))Yb](2)(cis-OCH=CHO) (2), a formate complex [(Tp(Ad,iPr))Yb(kappa(2)-O2CH)(THF)] (3), and a trivalent ytterbium ethenetetrathiolate complex [(Tp(Ad,iPr))-Yb-III](2)(C2S4) (4), respectively. DFT calculations were carried out to elucidate the reaction profiles of complexes 3 and 4.
Published: 2022
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40. Controlled monodefluorination and alkylation of C(sp3)–F bonds by lanthanide photocatalysts: importance of metal–ligand cooperativity

Author: Amy E. Kynman, Luca K. Elghanayan, Addison N. Desnoyer, Yan Yang, Laurent Sévery, Andrea Di Giuseppe, T. Don Tilley, Laurent Maron, and Polly L. Arnold
Subjects: General Chemistry
Abstract: The controlled functionalization of a single fluorine in a CF3 group is difficult and rare. Photochemical C–F bond functionalization is achieved using catalysts made from a range of earth-abundant lanthanides by using a ligand that enables M–L cooperativity.
Published: 2022

41. Solvent‐Dependent Oxidative Addition and Reductive Elimination of H$_{2}$ Across a Gallium‐Zinc Bond

Author: Louis J. Morris, Thayalan Rajeshkumar, Akira Okumura, Laurent Maron, Jun Okuda, Rheinisch-Westfälische Technische Hochschule Aachen University (RWTH), Chemistry Research Laboratory [Oxford, UK], University of Oxford, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: ddc:540, [CHIM]Chemical Sciences, General Chemistry, Dehydrogenation, Hydrogenation, Heterometallic Complexes, Catalysis, Main Group Compounds, Solvent Effects
Abstract: Angewandte Chemie / International edition 61(36), e202208855 (2022). doi:10.1002/anie.202208855, Published by Wiley-VCH, Weinheim
Published: 2022
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42. Structure, reactivity and luminescence studies of triphenylsiloxide complexes of tetravalent lanthanides

Author: Aurélien R. Willauer, Iskander Douair, Anne-Sophie Chauvin, Farzaneh Fadaei-Tirani, Jean-Claude G. Bünzli, Laurent Maron, Marinella Mazzanti, Ecole Polytechnique Fédérale de Lausanne (EPFL), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Swiss National Science Foundation, and Ecole Polytechnique Federale de Lausanne (EPFL)
Subjects: c-h, state, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, praseodymium(iii), spectra, ligands, ions, rare-earth, dysprosium, [CHIM.COOR]Chemical Sciences/Coordination chemistry, General Chemistry, ray crystal-structure, solvation
Abstract: International audience; Among the 14 lanthanide elements (Ce-Lu), until recently, the tetravalent oxidation state was readily accessible in solution only for cerium while Pr(iv), Nd(iv), Dy(iv) and Tb(iv) had only been detected in the solid state. The triphenylsiloxide ligand recently allowed the isolation of molecular complexes of Tb(iv) and Pr(iv) providing an unique opportunity of investigating the luminescent properties of Ln(iv) ions. Here we have expanded the coordination studies of the triphenylsiloxide ligand with Ln(iii) and Ln(iv) ions and we report the first observed luminescence emission spectra of Pr(iv) complexes which are assigned to a ligand-based emission on the basis of the measured lifetime and computational studies. Binding of the ligand to the Pr(iv) ion leads to an unprecedented large shift of the ligand triplet state which is relevant for future applications in materials science.
Published: 2022
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43. Correction: Isolation of C1 through C4 derivatives from CO using heteroleptic uranium(<scp>iii</scp>) metallocene aryloxide complexes

Author: Robert J. Ward, Iker del Rosal, Steven P. Kelley, Laurent Maron, and Justin R. Walensky
Subjects: General Chemistry
Abstract: Correction for ‘Isolation of C1 through C4 derivatives from CO using heteroleptic uranium(iii) metallocene aryloxide complexes’ by Robert J. Ward et al., Chem. Sci., 2023, 14, 2024–2032, https://doi.org/10.1039/D2SC06375A.
Published: 2023
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44. A mononuclear divalent ytterbium hydrido complex supported by a super-bulky scorpionate ligand

Author: Lanxiao Zhao, Peng Deng, Xianghui Shi, Thayalan Rajeshkumar, Jianhua Cheng, Laurent Maron, Shanghai Institute of Materia Medica - Chinese Academy of Sciences [Shanghai], Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), National Natural Science Foundation of China [21901238, 21971232], and HPCs CALcul en Midi-Pyrenees (CALMIP-EOS) [1415]
Subjects: Ytterbium, chemistry.chemical_classification, Hydride, Ligand, Chemistry, Metals and Alloys, chemistry.chemical_element, General Chemistry, Scorpionate ligand, Medicinal chemistry, Catalysis, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Divalent, Hexane, chemistry.chemical_compound, Deprotonation, Hydrogenolysis, Materials Chemistry, Ceramics and Composites, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]
Abstract: International audience; The first mononuclear divalent ytterbium hydride complex [(Tp(Ad,iPr))Yb(H)(THF)] (Tp(Ad,iPr) = hydrotris(3-adamantyl-5-isopropyl-pyrazolyl)borate) (2) bearing a terminal hydrido ligand was obtained by hydrogenolysis of the benzyl precursor in hexane. Complex 2 exhibited two different reaction patterns towards allenes: Yb-H addition with cyclohexylallene and deprotonation of 1,1-dimethylallene.
Published: 2021
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45. Evidence for ligand- and solvent-induced disproportionation of uranium(IV)

Author: Jingzhen Du, Floriana Tuna, Ashley J. Wooles, Erli Lu, Iskander Douair, Stephen T. Liddle, John A. Seed, Laurent Maron, University of Manchester [Manchester], Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), UK Engineering and Physical Sciences Research Council [EP/K024000/1, EP/M027015/1, EP/P001386/1, EP/S033181/1], European Research Council [CoG612724], Royal Society [UF110005], Leverhulme Trust [RF-2018-545\4], Humboldt Foundation, CalMip, University of Manchester, COST Action [CM1006], and UK National Electron Paramagnetic Resonance Facility
Subjects: inorganic chemicals, Science, Inorganic chemistry, General Physics and Astronomy, chemistry.chemical_element, Disproportionation, Redox, complex mixtures, General Biochemistry, Genetics and Molecular Biology, Article, Theoretical chemistry, chemistry.chemical_compound, Oxidation state, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Multidisciplinary, technology, industry, and agriculture, Isolobal principle, General Chemistry, Uranium, Alkali metal, Toluene, Coordination chemistry, chemistry, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Trifluoromethanesulfonate
Abstract: Disproportionation, where a chemical element converts its oxidation state to two different ones, one higher and one lower, underpins the fundamental chemistry of metal ions. The overwhelming majority of uranium disproportionations involve uranium(III) and (V), with a singular example of uranium(IV) to uranium(V/III) disproportionation known, involving a nitride to imido/triflate transformation. Here, we report a conceptually opposite disproportionation of uranium(IV)-imido complexes to uranium(V)-nitride/uranium(III)-amide mixtures. This is facilitated by benzene, but not toluene, since benzene engages in a redox reaction with the uranium(III)-amide product to give uranium(IV)-amide and reduced arene. These disproportionations occur with potassium, rubidium, and cesium counter cations, but not lithium or sodium, reflecting the stability of the corresponding alkali metal-arene by-products. This reveals an exceptional level of ligand- and solvent-control over a key thermodynamic property of uranium, and is complementary to isolobal uranium(V)-oxo disproportionations, suggesting a potentially wider prevalence possibly with broad implications for the chemistry of uranium., Disproportion of uranium(IV) is rare, as it is usually the stable product of uranium(III) or (V) disproportionation. Here, the authors report uranium(IV) disproportionation to uranium(III) and (V) revealing ligand and solvent control over a key thermodynamic property of uranium
Published: 2021
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46. Access to Hydroxy‐Functionalized Polypropylene through Coordination Polymerization

Author: Tiantian Wang, Yuanhao Zhong, Dongmei Cui, Laurent Maron, Iskander Douair, Chunji Wu, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences [Changchun Branch] (CAS), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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: 010405 organic chemistry, Allene, technology, industry, and agriculture, macromolecular substances, General Chemistry, 010402 general chemistry, 01 natural sciences, Catalyst poisoning, Catalysis, 0104 chemical sciences, chemistry.chemical_compound, Hydroboration, Monomer, chemistry, Polymerization, Polymer chemistry, Copolymer, Coordination polymerization, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Allyl alcohol
Abstract: Preparation of polyethylenes containing hydroxy groups has been already industrialized through radical copolymerization under harsh conditions followed by alcoholysis. By contrast, hydroxy-functionalized polypropylene has proven a rather challenging goal in polymer science. Propylene can't be polymerized through a radical mechanism, and its coordination copolymerization with polar monomers is frustrated by catalyst poisoning. Herein, we report a new strategy to reach this target. The coordination polymerization of allenes by rare-earth-metal precursors affords pure 1,2-regulated polyallenes, which are facilely transformed into poly(allyl alcohol) analogues by subsequent hydroboration/oxidation. Strikingly, the copolymerization of allenes and propylene gives unprecedented hydroxy-functionalized polypropylene after post-polymerization modification. Mechanistic elucidation by DFT simulation suggests kinetic rather than thermodynamic control.
Published: 2020
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47. A transient lanthanum phosphinidene complex

Author: Stephan Hohloch, Laurent Maron, Roland Schoch, Fabian A. Watt, Karl N. McCabe, University of Paderborn, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and Universität Innsbruck [Innsbruck]
Subjects: Reaction mechanism, Metals and Alloys, chemistry.chemical_element, General Chemistry, Catalysis, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Crystallography, Deprotonation, chemistry, Phosphinidene, Materials Chemistry, Ceramics and Composites, Lanthanum, Thermal stability, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]
Abstract: Deprotonation of the terminal phosphido complex (PN)2La(PHMes) (1) results in the C-H-activation of one of the PN ligands, formally retaining the PHMes group. The reaction mechanism and the possible involvement of the transient phosphinidene complex 2 are investigated by theoretical and chemical means including a deuteration experiment employing (PN)2La(PDMes) (1-d). Furthermore, the thermal stability of product [K(2.2.2-cryptand)][(PN)(PNcyclo)La(PHMes)] (3b) is examined, giving the diphosphido complex [K(2.2.2-cryptand)][(PN)2La(P2Mes2)] (6).
Published: 2020
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48. Construction of heterometallic clusters with multiple uranium–metal bonds by using dianionic nitrogen–phosphorus ligands

Author: Shuao Wang, Genfeng Feng, Karl N. McCabe, Laurent Maron, Congqing Zhu, Nanjing Normal Univ, Key Lab Virtual Geog Environm, Minist Educ, Nanjing 210023, Peoples R China, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Soochow University, and Nanjing University (NJU)
Subjects: chemistry.chemical_element, General Chemistry, Uranium, Nitrogen phosphorus, Catalysis, Metal, Chemistry, Crystallography, chemistry, Transition metal, Group (periodic table), visual_art, visual_art.visual_art_medium, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Bimetallic strip, Metallic bonding
Abstract: Compared with the prevalent metal–metal bond in transition metals, examples of the actinide–metal bond in heterometallic clusters are rare. Herein, a series of heterometallic clusters with multiple uranium–metal bonds has been prepared based on two newly synthesized nitrogen–phosphorus ligands L1 {O[(CH2)2NHP(iPr)2]2} and L2 {[CH2O(CH2)2NHP(iPr)2]2}. Different P–P distances, 6.069 and 4.464 Å, are observed in the corresponding uranium complexes 1 {O[(CH2)2NP(iPr)2]2UCl2} and 2 {[CH2O(CH2)2NP(iPr)2]2UCl2}, respectively, and lead to the different coordination modes with transition metals. The reactions of zero-valent group 10 metal compounds with complex 1 generate heterometallic clusters (3-U2Ni2 and 4-U2Pd2) featuring four uranium–metal bonds; whereas reactions with 2 afford one-dimensional metal-chain 5-(UNi)n, bimetallic species 6-UPd, and a tri-platinum bridged diuranium molecular cluster 7-U2Pt3. Complex 5-(UNi)n represents the first infinite chain containing the U–M bond and 7-U2Pt3 is the first species with multiple U–Pt bonds. This study further highlights the important role of ligands in the construction of multiple uranium–metal bonds and may allow the synthesis of novel d–f heterometallic clusters and the investigation of their applications in catalysis and small-molecule activation., Compared with the prevalent metal–metal bond in transition metals, examples of the actinide–metal bond in heterometallic clusters are rare.
Published: 2020
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49. Selective oxo ligand functionalisation and substitution reactivity in an oxo/catecholate-bridged UIV/UIV Pacman complex

Author: Polly L. Arnold, Laurent Maron, Iskander Douair, Jason B. Love, Bradley E. Cowie, University of Edinburgh, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry [Berkeley], University of California [Berkeley] (UC Berkeley), and University of California (UC)-University of California (UC)
Subjects: 010405 organic chemistry, Chemistry, Ligand, General Chemistry, 010402 general chemistry, 01 natural sciences, Medicinal chemistry, Small molecule, 0104 chemical sciences, Chalcogen, Molecular geometry, Nucleophile, Oxidation state, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Bimetallic strip, Lone pair
Abstract: The oxo- and catecholate-bridged UIV/UIV Pacman complex [{(py)UIVOUIV(μ-O2C6H4)(py)}(LA)] A (LA = a macrocyclic "Pacman" ligand; anthracenylene hinge between N4-donor pockets, ethyl substituents on meso-carbon atom of each N4-donor pocket) featuring a bent UIV-O-UIV oxo bridge readily reacts with small molecule substrates to undergo either oxo-atom functionalisation or substitution. Complex A reacts with H2O or MeOH to afford [{(py)UIV(μ-OH)2UIV(μ-O2C6H4)(py)}(LA)] (1) and [{(py)UIV(μ-OH)(μ-OMe)UIV(μ-O2C6H4)(py)}(LA)] (2), respectively, in which the bridging oxo ligand in A is substituted for two bridging hydroxo ligands or one bridging hydroxo and one bridging methoxy ligand, respectively. Alternatively, A reacts with either 0.5 equiv. of S8 or 4 equiv. of Se to provide [{(py)UIV(μ-η2:η2-E2)UIV(μ-O2C6H4)(py)}(LA)] (E = S (3), Se (4)) respectively, in which the [E2]2- ion bridges the two UIV centres. To the best of our knowledge, complex A is the first example of either a d- or f-block bimetallic μ-oxo complex that activates elemental chalcogens. Complex A also reacts with XeF2 or 2 equiv. of Me3SiCl to provide [{(py)UIV(μ-X)2UIV(μ-O2C6H4)(py)}(LA)] (X = F (5), Cl (6)), in which the oxo ligand has been substituted for two bridging halido ligands. Reacting A with either XeF2 or Me3SiCl in the presence of O(Bcat)2 at room temperature forms [{(py)UIV(μ-X)(μ-OBcat)UIV(μ-O2C6H4)(py)}(LA)] (X = F (5A), Cl (6A)), which upon heating to 80 °C is converted to 5 and 6, respectively. In order to probe the importance of the bent UIV-O-UIV motif in A on the observed reactivity, the bis(boroxido)-UIV/UIV complex, [{(py)(pinBO)UIVOUIV(OBpin)(py)}(LA)] (B), featuring a linear UIV-O-UIV bond angle was treated with H2O and Me3SiCl. Complex B reacts with two equiv. of either H2O or Me3SiCl to provide [{(py)HOUIVOUIVOH(py)}(LA)] (7) and [{(py)ClUIVOUIVCl(py)}(LA)] (8), respectively, in which reactions occur preferentially at the boroxido ligands, with the μ-oxo ligand unchanged. The formal UIV oxidation state is retained in all of the products 1-8, and selective reactions at the bridging oxo ligand in A is facilitated by: (1) its highly nucleophilic character which is a result of a non-linear UIV-O-UIV bond angle causing an increase in U-O bond covalency and localisation of the lone pairs of electrons on the μ-oxo group, and (2) the presence of the bridging catecholate ligand, which destabilises a linear oxo-bridging geometry and stabilises the resulting products.
Published: 2020
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50. Sterically controlled reductive oligomerisations of CO by activated magnesium(<scp>i</scp>) compounds: deltate vs. ethenediolate formation

Author: Laurent Maron, Dafydd D. L. Jones, Cameron Jones, K. Yuvaraj, Iskander Douair, School of Chemistry, Monash University [Clayton], Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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: Steric effects, Chemistry, Magnesium, Intramolecular force, Molecule, chemistry.chemical_element, Reactivity (chemistry), [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], General Chemistry, Reaction intermediate, Medicinal chemistry, Adduct
Abstract: An extremely bulky, symmetrical three-coordinate magnesium(i) complex, [{(TCHPNacnac)Mg}2] (TCHPNacnac = [{(TCHP)NCMe}2CH]−, TCHP = 2,4,6-tricyclohexylphenyl) has been prepared and shown to have an extremely long Mg–Mg bond (3.021(1) Å) for such a complex. It was shown not to react with either DMAP (4-dimethylaminopyridine) or CO. Three unsymmetrical 1 : 1 DMAP adducts of less bulky Mg–Mg bonded species have been prepared, viz. [(ArNacnac)Mg–Mg(DMAP)(ArNacnac)] (ArNacnac = [(ArNCMe)2CH]− Ar = 2,6-xylyl (Xyl), mesityl (Mes) or 2,6-diethylphenyl (Dep)), and their reactivity toward CO explored. Like the previously reported bulkier complex, [(DipNacnac)Mg–Mg(DMAP)(DipNacnac)] (Dip = 2,6-diisopropylphenyl), [(DepNacnac)Mg–Mg(DMAP)(DepNacnac)] reductively trimerises CO to give a rare example of a deltate complex, [{(DepNacnac)Mg(μ-C3O3)Mg(DMAP)(DepNacnac)}2]. In contrast, the two smaller adduct complexes react with only two CO molecules, ultimately giving unusual ethenediolate complexes [{(ArNacnac)Mg{μ-OC(H) Created by potrace 1.16, written by Peter Selinger 2001-2019 C(DMAP−H)O}Mg(ArNacnac)}2] (Ar = Xyl or Mes). DFT calculations show the latter reactions to proceed via reductive dimerizations of CO, and subsequent intramolecular C–H activation of Mg-ligated DMAP by “zig–zag” [C2O2]2− fragments of reaction intermediates. Calculations also suggest that magnesium deltate complexes are kinetic products in these reactions, while the magnesium ethenediolates are thermodynamic products. This study shows that subtle changes to the bulk of the reacting 1 : 1 DMAP–magnesium(i) adduct complexes can lead to fine steric control over the products arising from their CO reductive oligomerisations. Furthermore, it is found that the more activated nature of the adduct complexes, relative to their symmetrical, three-coordinate counterparts, [{(ArNacnac)Mg}2], likely derives more from the polarisation of the Mg–Mg bonds of the former, than the elongated nature of those bonds., Subtle changes to the bulk of 1 : 1 adducts of DMAP with magnesium(i) complexes leads to steric control over the products arising from their reductive oligomerisations of carbon monoxide.
Published: 2020
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