1
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Seed JA, Cleaves PA, Hatton GR, King DM, Tuna F, Wooles AJ, Chilton NF, Liddle ST. Reactivity of a triamidoamine terminal uranium(VI)-nitride with 3d-transition metal metallocenes. Chem Commun (Camb) 2024. [PMID: 39176420 PMCID: PMC11342066 DOI: 10.1039/d4cc03846k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2024] [Accepted: 08/13/2024] [Indexed: 08/24/2024]
Abstract
Reactions between [(TrenTIPS)UVIN] (1, TrenTIPS = {N(CH2CH2NSiPri3)3}3-) and [MII(η5-C5R5)2] (M/R = Cr/H, Mn/H, Fe/H, Ni/H) were intractable, but M/R = Co/H or Co/Me afforded [(TrenTIPS)UVN-(η1:η4-C5H5)CoI(η5-C5H5)] (2) and [(TrenTIPS)UIV-NH2] (3), respectively. For M/R = V/H [(TrenTIPS)UIV-NVIV(η5-C5H5)2] (4), was isolated. Complexes 2-4 evidence one-/two-electron uranium reductions, nucleophilic nitrides, and partial N-atom transfer.
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Affiliation(s)
- John A Seed
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
| | - Peter A Cleaves
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
| | - Georgina R Hatton
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
| | - David M King
- School of Chemistry, The University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Floriana Tuna
- Department of Chemistry and Photon Science Institute, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Ashley J Wooles
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
| | - Nicholas F Chilton
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
- Research School of Chemistry, The Australian National University, Sullivans Creek Road, Canberra, ACT, 2601, Australia.
| | - Stephen T Liddle
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
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2
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Burrow TG, Alcock NM, Huzan MS, Dunstan MA, Seed JA, Detlefs B, Glatzel P, Hunault MOJY, Bendix J, Pedersen KS, Baker ML. Determination of Uranium Central-Field Covalency with 3 d4 f Resonant Inelastic X-ray Scattering. J Am Chem Soc 2024; 146:22570-22582. [PMID: 39083620 PMCID: PMC11328134 DOI: 10.1021/jacs.4c06869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/02/2024]
Abstract
Understanding the nature of metal-ligand bonding is a major challenge in actinide chemistry. We present a new experimental strategy for addressing this challenge using actinide 3d4f resonant inelastic X-ray scattering (RIXS). Through a systematic study of uranium(IV) halide complexes, [UX6]2-, where X = F, Cl, or Br, we identify RIXS spectral satellites with relative energies and intensities that relate to the extent of uranium-ligand bond covalency. By analyzing the spectra in combination with ligand field density functional theory we find that the sensitivity of the satellites to the nature of metal-ligand bonding is due to the reduction of 5f interelectron repulsion and 4f-5f spin-exchange, caused by metal-ligand orbital mixing and the degree of 5f radial expansion, known as central-field covalency. Thus, this study furthers electronic structure quantification that can be obtained from 3d4f RIXS, demonstrating it as a technique for estimating actinide-ligand covalency.
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Affiliation(s)
- Timothy G Burrow
- Department of Chemistry, The University of Manchester, Manchester, M13 9PL, U.K
- The University of Manchester at Harwell, Diamond Light Source, Harwell Campus, OX11 0DE, U.K
- Centre for Radiochemistry Research, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K
| | - Nathan M Alcock
- Department of Chemistry, The University of Manchester, Manchester, M13 9PL, U.K
- The University of Manchester at Harwell, Diamond Light Source, Harwell Campus, OX11 0DE, U.K
- Centre for Radiochemistry Research, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K
| | - Myron S Huzan
- Department of Chemistry, The University of Manchester, Manchester, M13 9PL, U.K
- The University of Manchester at Harwell, Diamond Light Source, Harwell Campus, OX11 0DE, U.K
- Centre for Radiochemistry Research, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K
| | - Maja A Dunstan
- Department of Chemistry, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - John A Seed
- Department of Chemistry, The University of Manchester, Manchester, M13 9PL, U.K
- Centre for Radiochemistry Research, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K
| | - Blanka Detlefs
- European Synchrotron Radiation Facility, 38000 Grenoble, France
| | - Pieter Glatzel
- European Synchrotron Radiation Facility, 38000 Grenoble, France
| | | | - Jesper Bendix
- Department of Chemistry, University of Copenhagen, 1172 Copenhagen, Denmark
| | - Kasper S Pedersen
- Department of Chemistry, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Michael L Baker
- Department of Chemistry, The University of Manchester, Manchester, M13 9PL, U.K
- The University of Manchester at Harwell, Diamond Light Source, Harwell Campus, OX11 0DE, U.K
- Centre for Radiochemistry Research, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K
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3
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Hsueh FC, Barluzzi L, Rajeshkumar T, Scopelliti R, Zivkovic I, Maron L, Mazzanti M. Synthesis, structure and redox properties of single-atom bridged diuranium complexes supported by aryloxides. Dalton Trans 2024; 53:13416-13426. [PMID: 39051943 PMCID: PMC11320667 DOI: 10.1039/d4dt01819b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2024] [Accepted: 07/18/2024] [Indexed: 07/27/2024]
Abstract
Single-atom (group 15 and group 16 anions) bridged dimetallic complexes of low oxidation state uranium provide a convenient route to implement multielectron transfer and promote magnetic communication in uranium chemistry, but remain extremely rare. Here we report the synthesis, redox and magnetic properties of N3-, O2-, and S2- bridged diuranium complexes supported by bulky aryloxide ligands. The U(IV)/U(IV) nitride [Cs(THF)8][(U(OAr)3)2(μ-N)], 1 could be prepared and characterized but could not be reduced. Reduction of the neutral U(IV)/U(IV) complexes [(U(OAr)3)2(μ-X)] A (X = O) and B (X = S) led to the isolation and characterization of the U(IV)/U(III) and U(III)/U(III) analogues. Complexes [(K(THF)4)2(U(OAr)2)2(μ-S)2], 5 and [K(2.2.2-cryptand)]2[(U(OAr)3)2(μ-S)], 6 are the first examples of U(III) sulphide bridged complexes. Computational studies and redox properties allow the reactivity of the dimetallic complexes to be related to their electronic structure.
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Affiliation(s)
- Fang-Che Hsueh
- Group of Coordination Chemistry, Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland.
| | - Luciano Barluzzi
- Group of Coordination Chemistry, Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland.
| | - Thayalan Rajeshkumar
- Laboratoire de Physique et Chimie des Nano-objets, Institut National des Sciences Appliquées, 31077 Toulouse, Cedex 4, France
| | - Rosario Scopelliti
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Ivica Zivkovic
- Laboratory for Quantum Magnetism, Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Laurent Maron
- Laboratoire de Physique et Chimie des Nano-objets, Institut National des Sciences Appliquées, 31077 Toulouse, Cedex 4, France
| | - Marinella Mazzanti
- Group of Coordination Chemistry, Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland.
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4
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Patra K, Brennessel WW, Matson EM. Molecular Models of Atomically Dispersed Uranium at MoS 2 Surfaces Reveal Cooperative Mechanism of Water Reduction. J Am Chem Soc 2024; 146:20147-20157. [PMID: 38984489 PMCID: PMC11273346 DOI: 10.1021/jacs.4c05002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Revised: 06/26/2024] [Accepted: 06/26/2024] [Indexed: 07/11/2024]
Abstract
Single atoms of uranium supported on molybdenum sulfide surfaces (U@MoS2) have been recently demonstrated to facilitate the hydrogen evolution reaction (HER) through electrocatalysis. Theoretical calculations have predicted uranium hydroxide moieties bound to edge-sulfur atoms of MoS2 as a proposed transition state involved in the HER process. However, the isolation of relevant intermediates involved in this process remains a challenge, rendering mechanistic hypotheses unverified. The present work describes the isolation and characterization of a uranium-hydroxide intermediate on molybdenum sulfide surfaces using [(Cp*3Mo3S4)UCp*], a molecular model of a reduced uranium center supported at MoS2. Mechanistic investigations highlight the metalloligand cooperativity with uranium involved in the water activation pathway. The corresponding uranium-oxo analogue, [(Cp*3Mo3S4)Cp*U(═O)], was also accessed from the hydroxide cluster via hydrogen atom transfer and from [(Cp*3Mo3S4)UCp*] through an alternative direct oxygen atom transfer. These results provide an atomistic perspective on the reactivity of low-valent uranium at molybdenum sulfide surfaces toward water, modeling key intermediates associated with the HER of U@MoS2 catalysts.
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Affiliation(s)
- Kamaless Patra
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - William W. Brennessel
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Ellen M. Matson
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
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5
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Dan X, Du J, Zhang S, Seed JA, Perfetti M, Tuna F, Wooles AJ, Liddle ST. Arene-, Chlorido-, and Imido-Uranium Bis- and Tris(boryloxide) Complexes. Inorg Chem 2024; 63:9588-9601. [PMID: 38557081 PMCID: PMC11134490 DOI: 10.1021/acs.inorgchem.3c04275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 03/07/2024] [Accepted: 03/08/2024] [Indexed: 04/04/2024]
Abstract
We introduce the boryloxide ligand {(HCNDipp)2BO}- (NBODipp, Dipp = 2,6-di-isopropylphenyl) to actinide chemistry. Protonolysis of [U{N(SiMe3)2}3] with 3 equiv of NBODippH produced the uranium(III) tris(boryloxide) complex [U(NBODipp)3] (1). In contrast, treatment of UCl4 with 3 equiv of NBODippK in THF at room temperature or reflux conditions produced only [U(NBODipp)2(Cl)2(THF)2] (2) with 1 equiv of NBODippK remaining unreacted. However, refluxing the mixture of 2 and unreacted NBODippK in toluene instead of THF afforded the target complex [U(NBODipp)3(Cl)(THF)] (3). Two-electron oxidation of 1 with AdN3 (Ad = 1-adamantyl) afforded the uranium(V)-imido complex [U(NBODipp)3(NAd)] (4). The solid-state structure of 1 reveals a uranium-arene bonding motif, and structural, spectroscopic, and DFT calculations all suggest modest uranium-arene δ-back-bonding with approximately equal donation into the arene π4 and π5 δ-symmetry π* molecular orbitals. Complex 4 exhibits a short uranium(V)-imido distance, and computational modeling enabled its electronic structure to be compared to related uranium-imido and uranium-oxo complexes, revealing a substantial 5f-orbital crystal field splitting and extensive mixing of 5f |ml,ms⟩ states and mj projections. Complexes 1-4 have been variously characterized by single-crystal X-ray diffraction, 1H NMR, IR, UV/vis/NIR, and EPR spectroscopies, SQUID magnetometry, elemental analysis, and CONDON, F-shell, DFT, NLMO, and QTAIM crystal field and quantum chemical calculations.
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Affiliation(s)
- Xuhang Dan
- Department
of Chemistry and Centre for Radiochemistry Research, The University of Manchester, Oxford Road, Manchester M13 9PL, United
Kingdom
| | - Jingzhen Du
- Department
of Chemistry and Centre for Radiochemistry Research, The University of Manchester, Oxford Road, Manchester M13 9PL, United
Kingdom
| | - Shuhan Zhang
- Department
of Chemistry and Centre for Radiochemistry Research, The University of Manchester, Oxford Road, Manchester M13 9PL, United
Kingdom
| | - John A. Seed
- Department
of Chemistry and Centre for Radiochemistry Research, The University of Manchester, Oxford Road, Manchester M13 9PL, United
Kingdom
| | - Mauro Perfetti
- Department
of Chemistry Ugo Schiff, University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy
| | - Floriana Tuna
- Department
of Chemistry and Photon Science Institute, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Ashley J. Wooles
- Department
of Chemistry and Centre for Radiochemistry Research, The University of Manchester, Oxford Road, Manchester M13 9PL, United
Kingdom
| | - Stephen T. Liddle
- Department
of Chemistry and Centre for Radiochemistry Research, The University of Manchester, Oxford Road, Manchester M13 9PL, United
Kingdom
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6
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Li T, Heng Y, Wang D, Hou G, Zi G, Ding W, Walter MD. Uranium versus Thorium: A Case Study on a Base-Free Terminal Uranium Imido Metallocene. Inorg Chem 2024; 63:9487-9510. [PMID: 38048266 DOI: 10.1021/acs.inorgchem.3c03356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/06/2023]
Abstract
The structure of and bonding in two base-free terminal actinide imido metallocenes, [η5-1,2,4-(Me3C)3C5H2]2An═N(p-tolyl) (An = U (1), Th (1')) are compared and connected to their individual reactivity. While structurally rather similar, the U(IV) derivative 1 is slightly more sterically crowded. Furthermore, density functional theory (DFT) studies imply that the 5f orbital contribution to the bonding within the individual actinide imido An═N(p-tolyl) moieties is significantly larger for 1 than for 1', which makes the bonds between the [η5-1,2,4-(Me3C)3C5H2]2U2+ and [(p-tolyl)N]2- fragments more covalent. Therefore, steric and electronic factors impact the reactivity of these imido complexes. For example, complex 1 is inert toward internal alkynes, but it readily forms Lewis base adducts [η5-1,2,4-(Me3C)3C5H2]2U═N(p-tolyl)(L) (L = OPMe3 (6), dmap (9), PhCN (14), and 2,6-Me2PhNC (17)) with Me3PO, 4-dimethylaminopyridine (dmap), nitrile, PhCN, or isonitrile 2,6-Me2PhNC. It may also react as a nucleophile or undergo a [2 + 2] cycloaddition with CS2, isothiocyanates, thio-ketones, ketones, lactides, and acyl nitriles, forming the four- or five-membered metallaheteroacycles, terminal sulfido, or oxido complexes, and cyanide amidate complexes, respectively. In contrast, after the addition of aldehyde p-tolylCHO, the tetranuclear complex [η5-1,2,4-(Me3C)3C5H2]4[OCH(p-tolyl)CH(p-tolyl)O]2U4O4 (10) is isolated. However, while 1 is unreactive toward dicyclohexylcarbodiimide (DCC), an equilibrium exists in benzene solution between N,N'-diisopropylcarbodiimide (DIC), 1, and the four-membered metallaheterocycle [η5-1,2,4-(Me3C)3C5H2]2U[N(p-tolyl)C(═NiPr)N(iPr)] (12). Furthermore, 1 may also engage in single- and two-electron transfer processes. It is singly oxidized by Ph3CN3, CuI, Ph2S2, and Ph2Se2, yielding the uranium(V) imido complexes [η5-1,2,4-(Me3C)3C5H2]2U═N(p-tolyl)(X) (X = N3 (20), I (22), PhS (23), and PhSe (24)), or is doubly oxidized by organic azides (RN3) and 9-diazofluorene, forming the uranium(VI) bis-imido metallocenes [η5-1,2,4-(Me3C)3C5H2]2U═N(p-tolyl)(=NR) (R = p-tolyl (18), mesityl (19)) and [η5-1,2,4-(Me3C)3C5H2]2U=N(p-tolyl)[=NN=(9-C13H8)] (21), respectively.
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Affiliation(s)
- Tongyu Li
- Department of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Yi Heng
- Department of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Dongwei Wang
- Department of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Guohua Hou
- Department of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Guofu Zi
- Department of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Wanjian Ding
- Department of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Marc D Walter
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
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7
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Batov MS, Del Rosal I, Scopelliti R, Fadaei-Tirani F, Zivkovic I, Maron L, Mazzanti M. Multimetallic Uranium Nitride Cubane Clusters from Dinitrogen Cleavage. J Am Chem Soc 2023; 145:26435-26443. [PMID: 37991736 DOI: 10.1021/jacs.3c10617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2023]
Abstract
Dinitrogen cleavage provides an attractive but poorly studied route to the assembly of multimetallic nitride clusters. Here, we show that the monoelectron reduction of the dinitrogen complex [{U(OC6H2-But3-2,4,6)3}2(μ-η2:η2-N2)], 1, allows us to generate, for the first time, a uranium complex presenting a rare triply reduced N2 moiety ((μ-η2:η2-N2)•3-). Importantly, the bound dinitrogen can be further reduced, affording the U4N4 cubane cluster, 3, and the U6N6 edge-shared cubane cluster, 4, thus showing that (N2)•3- can be an intermediate in nitride formation. The tetranitride cluster showed high reactivity with electrophiles, yielding ammonia quantitatively upon acid addition and promoting CO cleavage to yield quantitative conversion of nitride into cyanide. These results show that dinitrogen reduction provides a versatile route for the assembly of large highly reactive nitride clusters, with U6N6 providing the first example of a molecular nitride of any metal formed from a complete cleavage of three N2 molecules.
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Affiliation(s)
- Mikhail S Batov
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Iker Del Rosal
- Laboratoire de Physique et Chimie des Nano-Objets, Institut National des Sciences Appliquées, 31077 Toulouse Cedex 4, France
| | - Rosario Scopelliti
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Farzaneh Fadaei-Tirani
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Ivica Zivkovic
- Laboratory for Quantum Magnetism, Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Laurent Maron
- Laboratoire de Physique et Chimie des Nano-Objets, Institut National des Sciences Appliquées, 31077 Toulouse Cedex 4, France
| | - Marinella Mazzanti
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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8
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Li T, Wang D, Heng Y, Hou G, Zi G, Walter MD. Reactivity of a Lewis base-supported uranium terminal imido metallocene towards small molecules. Dalton Trans 2023; 52:13618-13630. [PMID: 37698550 DOI: 10.1039/d3dt02165c] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2023]
Abstract
The Lewis base-supported uranium terminal imido metallocene [η5-1,2,4-(Me3Si)3C5H2]2UN(p-tolyl)(dmap) (1) readily reacts with various small molecules such as internal alkynes, isothiocyanates, thioketones, amidates, organic nitriles and imines, chlorosilanes, copper iodide, diphenyl disulfide, organic azides and diazoalkane derivatives. For example, treatment of 1 with PhCCCCPh and PhNCS forms metallaheterocycles originating from a [2 + 2] cycloaddition to yield [η5-1-(p-tolyl)NC(Ph)CHCC(Ph)CH2Si(Me)2-2,4-(Me3Si)2C5H2][η5-1,2,4-(Me3Si)3C5H2]U (2) and [η5-1,2,4-(Me3Si)3C5H2]2U[N(p-tolyl)C(NPh)S](dmap) (3), respectively. The reaction of 1 with the thioketone Ph2CS forms the known uranium sulfido complex [η5-1,2,4-(Me3Si)3C5H2]2US(dmap) (4), which reacts with a second molecule of Ph2CS to give the disulfido compound [η5-1,2,4-(Me3Si)3C5H2]2U(S2CPh2) (5). The imido moiety also promotes deprotonation reactions as illustrated in the reactions with the amide PhCONH(p-tolyl), the nitrile PhCH2CN and the imine (p-tolyl)2CNH to form the bis-amidate [η5-1,2,4-(Me3Si)3C5H2]2U[OC(Ph)N(p-tolyl)]2 (7), and the iminato complexes [η5-1,2,4-(Me3Si)3C5H2]2U[N(p-tolyl)C(CH2Ph)NH](NCCHPh) (8) and [η5-1,2,4-(Me3Si)3C5H2]2U[NH(p-tolyl)][NC(p-tolyl)2] (9), respectively. Addition of PhSiH2Cl to 1 yields [η5-1,2,4-(Me3Si)3C5H2]2U(Cl)[N(p-tolyl)SiH2Ph] (10). In contrast, the uranium(V) imido complexes [η5-1,2,4-(Me3Si)3C5H2]2UN(p-tolyl)(I) (11) and [η5-1,2,4-(Me3Si)3C5H2]2UN(p-tolyl)(SPh) (12), may be isolated upon addition of CuI or Ph2S2 to 1, respectively. Uranium(VI) bis-imido metallocenes [η5-1,2,4-(Me3Si)3C5H2]2UN(p-tolyl)(NR) (R = p-tolyl (13), mesityl (14)) and [η5-1,2,4-(Me3Si)3C5H2]2UN(p-tolyl)[NN(9-C13H8)] (15) are accessible from 1 on exposure to RN3 (R = p-tolyl, mesityl) and 9-diazofluorene, respectively. Complexes 2, 3, 5, and 7-15 were characterized by various spectroscopic techniques and, in addition, compounds 2, 3, 5, and 7-13 were structurally authenticated by single-crystal X-ray diffraction analyses.
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Affiliation(s)
- Tongyu Li
- Department of Chemistry, Beijing Normal University, Beijing 100875, China.
| | - Dongwei Wang
- Department of Chemistry, Beijing Normal University, Beijing 100875, China.
| | - Yi Heng
- Department of Chemistry, Beijing Normal University, Beijing 100875, China.
| | - Guohua Hou
- Department of Chemistry, Beijing Normal University, Beijing 100875, China.
| | - Guofu Zi
- Department of Chemistry, Beijing Normal University, Beijing 100875, China.
| | - Marc D Walter
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany.
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9
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Deng C, Liang J, Sun R, Wang Y, Fu PX, Wang BW, Gao S, Huang W. Accessing five oxidation states of uranium in a retained ligand framework. Nat Commun 2023; 14:4657. [PMID: 37537160 PMCID: PMC10400547 DOI: 10.1038/s41467-023-40403-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 07/24/2023] [Indexed: 08/05/2023] Open
Abstract
Understanding and exploiting the redox properties of uranium is of great importance because uranium has a wide range of possible oxidation states and holds great potential for small molecule activation and catalysis. However, it remains challenging to stabilise both low and high-valent uranium ions in a preserved ligand environment. Herein we report the synthesis and characterisation of a series of uranium(II-VI) complexes supported by a tripodal tris(amido)arene ligand. In addition, one- or two-electron redox transformations could be achieved with these compounds. Moreover, combined experimental and theoretical studies unveiled that the ambiphilic uranium-arene interactions are the key to balance the stabilisation of low and high-valent uranium, with the anchoring arene acting as a δ acceptor or a π donor. Our results reinforce the design strategy to incorporate metal-arene interactions in stabilising multiple oxidation states, and open up new avenues to explore the redox chemistry of uranium.
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Affiliation(s)
- Chong Deng
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China
| | - Jiefeng Liang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China
| | - Rong Sun
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China
- Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing, 100871, P. R. China
| | - Yi Wang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China
| | - Peng-Xiang Fu
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China
| | - Bing-Wu Wang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China
- Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing, 100871, P. R. China
| | - Song Gao
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China
- Spin-X Institute, School of Chemistry and Chemical Engineering, State Key Laboratory of Luminescent Materials and Devices, Guangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional Materials, South China University of Technology, Guangzhou, 510641, P. R. China
| | - Wenliang Huang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China.
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10
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Su W, Rajeshkumar T, Xiang L, Maron L, Ye Q. Facile Synthesis of Uranium Complexes with a Pendant Borane Lewis Acid and 1,2-Insertion of CO into a U-N Bond. Angew Chem Int Ed Engl 2022; 61:e202212823. [PMID: 36256540 PMCID: PMC10099876 DOI: 10.1002/anie.202212823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Indexed: 11/18/2022]
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.
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Affiliation(s)
- Wei Su
- School of Chemistry and Environmental Engineering, Anhui Polytechnic University, 241000, Wuhu, China.,Department of Chemistry, Southern University of Science and Technology, 1088 Xueyuan Blvd., Xili, Nanshan District, 518055, Shenzhen, China
| | - Thayalan Rajeshkumar
- Laboratoire de Physique et Chimie des Nanoobjets, INSA, CNRS, UPS, Université de Toulouse, 31077, Toulouse, France
| | - Libo Xiang
- Department of Chemistry, Southern University of Science and Technology, 1088 Xueyuan Blvd., Xili, Nanshan District, 518055, Shenzhen, China.,Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Laurent Maron
- Laboratoire de Physique et Chimie des Nanoobjets, INSA, CNRS, UPS, Université de Toulouse, 31077, Toulouse, France
| | - Qing Ye
- Department of Chemistry, Southern University of Science and Technology, 1088 Xueyuan Blvd., Xili, Nanshan District, 518055, Shenzhen, China.,Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
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11
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Löffler ST, Hümmer J, Scheurer A, Heinemann FW, Meyer K. Unprecedented pairs of uranium (iv/v) hydroxido and (iv/v/vi) oxido complexes supported by a seven-coordinate cyclen-anchored tris-aryloxide ligand. Chem Sci 2022; 13:11341-11351. [PMID: 36320575 PMCID: PMC9533418 DOI: 10.1039/d2sc02736d] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 07/30/2022] [Indexed: 08/05/2023] Open
Abstract
We present the synthesis and reactivity of a newly developed, cyclen-based tris-aryloxide ligand precursor, namely cyclen(Me)( t-Bu,t-BuArOH)3, and its coordination chemistry to uranium. The corresponding uranium(iii) complex [UIII((OAr t-Bu,t-Bu)3(Me)cyclen)] (1) was characterized by 1H NMR analysis, CHN elemental analysis and UV/vis/NIR electronic absorption spectroscopy. Since no single-crystals suitable for X-ray diffraction analysis could be obtained from this precursor, 1 was oxidized with methylene chloride or silver fluoride to yield [(cyclen(Me)( t-Bu,t-BuArO)3)UIV(X)] (X = Cl (2), F (3)), which were unambiguously characterized and successfully crystallized to gain insight into the molecular structure by single-crystal X-ray diffraction analysis (SC-XRD). Further, the activation of H2O and N2O by 1 is presented, resulting in the U(iv) complex [(cyclen(Me)( t-Bu,t-BuArO)3)UIV(OH)] (4) and the U(v) complex [(cyclen(Me)( t-Bu,t-BuArO)3)UV(O)] (6). Complexes 2, 3, 4, and 6 were characterized by 1H NMR analysis, CHN elemental analysis, UV/vis/NIR electronic absorption spectroscopy, IR vibrational spectroscopy, and SQUID magnetization measurements as well as cyclic voltammetry. Furthermore, chemical oxidation of 3, 4, and 6 with AgF or AgSbF6 was achieved leading to complexes [(cyclen(Me)( t-Bu,t-BuArO)3)UV(F)2] (5), [(cyclen(Me)( t-Bu,t-BuArO)3)UV(OH)][SbF6] (7), and [(cyclen(Me)( t-Bu,t-BuArO)3)UVI(O)][SbF6] (8). Finally, reduction of 7 with KC8 yielded a U(iv) complex, spectroscopically and magnetochemically identified as K[(cyclen(Me)( t-Bu,t-BuArO)3)UIV(O)].
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Affiliation(s)
- Sascha T Löffler
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Department of Chemistry and Pharmacy Inorganic Chemistry Egerlandstraße 1 91058 Erlangen Germany
| | - Julian Hümmer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Department of Chemistry and Pharmacy Inorganic Chemistry Egerlandstraße 1 91058 Erlangen Germany
| | - Andreas Scheurer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Department of Chemistry and Pharmacy Inorganic Chemistry Egerlandstraße 1 91058 Erlangen Germany
| | - Frank W Heinemann
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Department of Chemistry and Pharmacy Inorganic Chemistry Egerlandstraße 1 91058 Erlangen Germany
| | - Karsten Meyer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Department of Chemistry and Pharmacy Inorganic Chemistry Egerlandstraße 1 91058 Erlangen Germany
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12
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Wang P, Zhao Y, Zhu C. Photolysis, Thermolysis, and Reduction of a Uranium Azide Complex Supported by a Double-Layer N–P Ligand. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Penglong Wang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Yue Zhao
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Congqing Zhu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
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13
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Birnoschi L, Chilton NF. Hyperion: A New Computational Tool for Relativistic Ab Initio Hyperfine Coupling. J Chem Theory Comput 2022; 18:4719-4732. [PMID: 35776849 PMCID: PMC9367016 DOI: 10.1021/acs.jctc.2c00257] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
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Herein we describe Hyperion, a new program for computing
relativistic picture-change-corrected magnetic resonance parameters
from scalar relativistic active space wave functions, with or without
spin–orbit coupling (SOC) included a posteriori. Hyperion also includes a new orbital decomposition method
for assisting active space selection for calculations of hyperfine
coupling. For benchmarking purposes, we determine hyperfine coupling
constants of selected alkali metal, transition metal, and lanthanide
atoms, based on complete active space self-consistent field spin–orbit
calculations in OpenMolcas. Our results are in excellent agreement
with experimental data from atomic spectroscopy as well as theoretical
predictions from four-component relativistic calculations.
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Affiliation(s)
- Letitia Birnoschi
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - Nicholas F Chilton
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
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14
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Seed JA, Vondung L, Barton F, Wooles AJ, Lu E, Gregson M, Adams RW, Liddle ST. A Series of Rare‐Earth Mesoionic Carbene Complexes. Chemistry 2022; 28:e202200761. [DOI: 10.1002/chem.202200761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Indexed: 11/05/2022]
Affiliation(s)
- John A. Seed
- Department of Chemistry The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Lisa Vondung
- Department of Chemistry The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Franky Barton
- Department of Chemistry The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Ashley J. Wooles
- Department of Chemistry The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Erli Lu
- Department of Chemistry The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Matthew Gregson
- Department of Chemistry The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Ralph W. Adams
- Department of Chemistry The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Stephen T. Liddle
- Department of Chemistry The University of Manchester Oxford Road Manchester M13 9PL UK
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15
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King DM, Atkinson BE, Chatelain L, Gregson M, Seed JA, Wooles AJ, Kaltsoyannis N, Liddle ST. Uranium-nitride chemistry: uranium-uranium electronic communication mediated by nitride bridges. Dalton Trans 2022; 51:8855-8864. [PMID: 35622422 PMCID: PMC9171730 DOI: 10.1039/d2dt00998f] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Treatment of [UIV(N3)(TrenTIPS)] (1, TrenTIPS = {N(CH2CH2NSiPri3)3}3-) with excess Li resulted in the isolation of [{UIV(μ-NLi2)(TrenTIPS)}2] (2), which exhibits a diuranium(IV) 'diamond-core' dinitride motif. Over-reduction of 1 produces [UIII(TrenTIPS)] (3), and together with known [{UV(μ-NLi)(TrenTIPS)}2] (4) an overall reduction sequence 1 → 4 → 2 → 3 is proposed. Attempts to produce an odd-electron nitride from 2 resulted in the formation of [{UIV(TrenTIPS)}2(μ-NH)(μ-NLi2)Li] (5). Use of heavier alkali metals did not result in the formation of analogues of 2, emphasising the role of the high charge-to-radius-ratio of lithium stabilising the charge build up at the nitride. Variable-temperature magnetic data for 2 and 5 reveal large low-temperature magnetic moments, suggesting doubly degenerate ground states, where the effective symmetry of the strong crystal field of the nitride dominates over the spin-orbit coupled nature of the ground multiplet of uranium(IV). Spin Hamiltonian modelling of the magnetic data for 2 and 5 suggest U⋯U anti-ferromagnetic coupling of -4.1 and -3.4 cm-1, respectively. The nature of the U⋯U electronic communication was probed computationally, revealing a borderline case where the prospect of direct uranium-uranium bonding was raised, but in-depth computational analysis reveals that if any uranium-uranium bonding is present it is weak, and instead the nitride centres dominate the mediation of U⋯U electronic communication. This highlights the importance of obtaining high-level ab initio insight when probing potential actinide-actinide electronic communication and bonding in weakly coupled systems. The computational analysis highlights analogies between the 'diamond-core' dinitride of 2 and matrix-isolated binary U2N2.
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Affiliation(s)
- David M King
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Benjamin E Atkinson
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
| | - Lucile Chatelain
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
| | - Matthew Gregson
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
| | - John A Seed
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
| | - Ashley J Wooles
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
| | - Nikolas Kaltsoyannis
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
| | - Stephen T Liddle
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
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16
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Seed JA, Vondung L, Adams RW, Wooles AJ, Lu E, Liddle ST. Mesoionic Carbene Complexes of Uranium(IV) and Thorium(IV). Organometallics 2022; 41:1353-1363. [PMID: 36157256 PMCID: PMC9490841 DOI: 10.1021/acs.organomet.2c00120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Indexed: 11/30/2022]
Abstract
![]()
We
report the synthesis and characterization of uranium(IV) and
thorium(IV) mesoionic carbene complexes [An{N(SiMe3)2}2(CH2SiMe2NSiMe3){MIC}] (An = U, 4U and Th, 4Th; MIC =
{CN(Me)C(Me)N(Me)CH}), which represent rare examples of actinide mesoionic
carbene linkages and the first example of a thorium mesoionic carbene
complex. Complexes 4U and 4Th were prepared
via a C–H activation intramolecular cyclometallation reaction
of actinide halides, with concomitant formal 1,4-proton migration
of an N-heterocyclic olefin (NHO). Quantum chemical
calculations suggest that the An–carbene bond comprises only
a σ-component, in contrast to the uranium(III) analogue [U{N(SiMe3)2}3(MIC)] (1) where computational
studies suggested that the 5f3 uranium(III) ion engages
in a weak one-electron π-backbond to the MIC. This highlights
the varying nature of actinide-MIC bonding as a function of actinide
oxidation state. In solution, 4Th exists in equilibrium
with the Th(IV) metallacycle [Th{N(SiMe3)2}2(CH2SiMe2NSiMe3)] (6Th) and free NHO (3). The thermodynamic parameters
of this equilibrium were probed using variable-temperature NMR spectroscopy
yielding an entropically favored but enthalpically endothermic process
with an overall reaction free energy of ΔG298.15K = 0.89 kcal mol–1. Energy decomposition
analysis (EDA-NOCV) of the actinide–carbon bonds in 4U and 4Th reveals that the former is enthalpically stronger
and more covalent than the latter, which accounts for the respective
stabilities of these two complexes.
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Affiliation(s)
- John A. Seed
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Lisa Vondung
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Ralph W. Adams
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Ashley J. Wooles
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Erli Lu
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Stephen T. Liddle
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K
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Abstract
Neptunium was the first actinide element to be artificially synthesized, yet, compared with its more famous neighbours uranium and plutonium, is less conspicuously studied. Most neptunium chemistry involves the neptunyl di(oxo)-motif, and transuranic compounds with one metal-ligand multiple bond are rare, being found only in extended-structure oxide, fluoride or oxyhalide materials. These combinations stabilize the required high oxidation states, which are otherwise challenging to realize for transuranic ions. Here we report the synthesis, isolation and characterization of a stable molecular neptunium(V)-mono(oxo) triamidoamine complex. We describe a strong Np≡O triple bond with dominant 5f-orbital contributions and σu > πu energy ordering, akin to terminal uranium-nitrides and di(oxo)-actinyls, but not the uranium-mono(oxo) triple bonds or other actinide multiple bonds reported so far. This work demonstrates that molecular high-oxidation-state transuranic complexes with a single metal-ligand bond can be stabilized and studied in isolation.
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18
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Dey S, Rajaraman G. Deciphering the Role of Symmetry and Ligand Field in Designing Three-Coordinate Uranium and Plutonium Single-Molecule Magnets. Inorg Chem 2022; 61:1831-1842. [PMID: 35025497 DOI: 10.1021/acs.inorgchem.1c02646] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Actinide single-molecule magnets (SMMs) have gained paramount interest in molecular magnetism as they offer a larger barrier height of magnetization (Ueff) reversal compared to the lanthanide analogue, thanks to their greater metal-ligand covalency. However, the reported actinide SMMs to date yield a relatively smaller Ueff as there is no established design principle to enhance Ueff values. To address this issue, we have employed ab initio CASSCF/CASPT2/NEVPT2 calculations to study a series of three-coordinate U3+ and Pu3+ SMMs. To begin with, we have studied two experimentally characterized U3+ ion-field-induced SMMs, namely, planar [U{N(SiMe2tBu)2}3] (1) and pyramidal [U{N(SiMe3)2}3] (2) complexes reported earlier. Both the complexes were found to stabilize mJ = |±1/2⟩ as the ground state with a very strong quantum tunneling of magnetization (QTM), rendering them unsuitable for SMMs. Our calculations reveal that in the pyramidal geometry (such as in 2), the energy of the 5f26d1 state is lowered compared to the planar geometry (as in 1), resulting in a slightly better SMM characteristic in the former. To unravel the effect of symmetry in magnetic properties, ab initio calculations were performed on two reported T-shaped complexes [U(NSiiPr2)2(I)] (3) and [U(NHAriPr6)2I] (4, AriPr6 = 2,6-(2,4,6-iPr3C6H2)2C6H3). Quite interestingly, mJ = |±9/2⟩ is found to be the ground state for both the complexes with a blocking barrier exceeding 900 cm-1. Furthermore, to decipher the effect of the transuranic element in magnetic anisotropy, ab initio calculations were extended to the Pu analogue of 2, [Pu{N(SiMe3)2}3] (5), which yields a record-breaking blocking barrier of ∼1933 cm-1. Among the three-coordinate geometries studied, the pyramidal geometry was found to offer substantial magnetic anisotropy for Pu3+ ions, while a T-shaped geometry is best suited for U3+ ions. While the chosen theoretical protocols' overestimation of barrier height cannot be avoided, these values are still several orders of magnitude larger than the Ueff values reported for any actinide SMMs and unveil a design principle for superior three-coordinate actinide-based SMMs.
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Affiliation(s)
- Sourav Dey
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Gopalan Rajaraman
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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