1
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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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2
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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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3
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Deng C, Liang J, Wang Y, Huang W. Reduction of Thorium Tris(amido)arene Complexes: Reversible Double and Single C-C Couplings. Inorg Chem 2024; 63:9676-9686. [PMID: 38696837 DOI: 10.1021/acs.inorgchem.4c00458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2024]
Abstract
The reduction chemistry of thorium complexes is less explored compared to that of their uranium counterparts. Here, we report the synthesis, characterization, and reduction chemistry of two thorium(IV) complexes, (AdTPBN3)ThCl (1) and (DtbpTPBN3)ThCl(THF) (4) [RTPBN3 = 1,3,5-[2-(RN)C6H4]3C6H3; R = 1-adamantyl (Ad) or 3,5-di-tert-butylphenyl (Dtbp); THF = tetrahydrofuran], supported by tripodal tris(amido)arene ligands with different N-substituents. Reduction of 1 with excessive potassium in n-pentane yielded a double C-C coupling product, [(AdTPBN3)ThK(Et2O)2]2 (3), featuring a unique tetraanionic tricyclic core. On the other hand, reduction of 4 with 1 equiv of KC8 in hexanes/1,2-dimethoxyethane (DME) afforded a single C-C coupling product, [(DtbpTPBN3)Th(DME)]2 (5), with a dianionic bis(cyclohexadienyl) core. The solid- and solution-state structures of dinuclear thorium(IV) complexes 3 and 5 were established by X-ray crystallography and NMR spectroscopy. In addition, reactivity studies show that 3 and 5 can behave as thorium(II) and thorium(III) synthons to reduce organic halides. For instance, 3 and 5 are able to reduce 4 and 2 equiv of benzyl chloride, respectively, to regenerate 1 and 4 with concomitant formation of dibenzyl. Reversible C-C couplings under redox conditions provide an alternative approach to exploiting the potential of thorium arene complexes in redox chemistry.
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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
| | - Yi Wang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, 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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4
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Du J, Dollberg K, Seed JA, Wooles AJ, von Hänisch C, Liddle ST. f-Element Zintl Chemistry: Actinide-Mediated Dehydrocoupling of H 2Sb 1- Affords the Trithorium and Triuranium Undeca-Antimontriide Zintl Clusters [{An(Tren TIPS)} 3(μ 3-Sb 11)] (An = Th, U; Tren TIPS = {N(CH 2CH 2NSi iPr 3) 3} 3-). Inorg Chem 2024. [PMID: 38767623 DOI: 10.1021/acs.inorgchem.4c00923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Reaction of the cesium antimonide complex [Cs(18C6)2][SbH2] (1, 18C6 = 18-crown-6 ether) with the triamidoamine actinide separated ion pairs [An(TrenTIPS)(L)][BPh4] (TrenTIPS = {N(CH2CH2NSiiPr3)3}3-; An/L = Th/DME (2Th); U/THF (2U)) affords the triactinide undeca-antimontriide Zintl clusters [{An(TrenTIPS)}3(μ3-Sb11)] (An = Th (3Th), U (3U)) by dehydrocoupling. Clusters 3Th and 3U provide two new examples of the Sb113- Zintl trianion and are unprecedented examples of molecular Sb113- being coordinated to anything since all previous reports featured isolated Sb113- Zintl trianions in separated ion quadruple formulations with noncoordinating cations. Quantum chemical calculations describe dominant ionic An-Sb interactions in 3Th and 3U, though the data suggest that the latter exhibits slightly more covalent An-Sb linkages than the former. Complexes 3Th and 3U have been characterized by single crystal X-ray diffraction, NMR, IR, and UV/vis/NIR spectroscopies, elemental analysis, and quantum chemical calculations.
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Affiliation(s)
- Jingzhen Du
- Department of Chemistry and Centre for Radiochemistry Research, The University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - Kevin Dollberg
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35043 Marburg, Germany
| | - John A Seed
- Department of Chemistry and Centre for Radiochemistry Research, 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
| | - Carsten von Hänisch
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35043 Marburg, Germany
| | - 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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5
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Du J, Dollberg K, Seed JA, Wooles AJ, von Hänisch C, Liddle ST. Thorium(IV)-antimony complexes exhibiting single, double, and triple polar covalent metal-metal bonds. Nat Chem 2024; 16:780-790. [PMID: 38378948 DOI: 10.1038/s41557-024-01448-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Accepted: 01/11/2024] [Indexed: 02/22/2024]
Abstract
There is continued burgeoning interest in metal-metal multiple bonding to further our understanding of chemical bonding across the periodic table. However, although polar covalent metal-metal multiple bonding is well known for the d and p blocks, it is relatively underdeveloped for actinides. Homometallic examples are found in spectroscopic or fullerene-confined species, and heterometallic variants exhibiting a polar covalent σ bond supplemented by up to two dative π bonds are more prevalent. Hence, securing polar covalent actinide double and triple metal-metal bonds under normal experimental conditions has been a fundamental target. Here we exploit the protonolysis and dehydrocoupling chemistry of the parent dihydrogen-antimonide anion, to report one-, two- and three-fold thorium-antimony bonds, thus introducing polar covalent actinide-metal multiple bonding under normal experimental conditions between some of the heaviest ions in the periodic table with little or no bulky-substituent protection at the antimony centre. This provides fundamental insights into heavy element multiple bonding, in particular the tension between orbital-energy-driven and overlap-driven covalency for the actinides in a relativistic regime.
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Affiliation(s)
- Jingzhen Du
- Department of Chemistry and Centre for Radiochemistry Research, The University of Manchester, Manchester, UK
- College of Chemistry, Zhengzhou University, Zhengzhou, China
| | - Kevin Dollberg
- Fachbereich Chemie and Wissenschaftliches Zentrum für Materialwissenschaften, Philipps-Universität Marburg, Marburg, Germany
| | - John A Seed
- Department of Chemistry and Centre for Radiochemistry Research, The University of Manchester, Manchester, UK
| | - Ashley J Wooles
- Department of Chemistry and Centre for Radiochemistry Research, The University of Manchester, Manchester, UK
| | - Carsten von Hänisch
- Fachbereich Chemie and Wissenschaftliches Zentrum für Materialwissenschaften, Philipps-Universität Marburg, Marburg, Germany.
| | - Stephen T Liddle
- Department of Chemistry and Centre for Radiochemistry Research, The University of Manchester, Manchester, UK.
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6
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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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7
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Li T, Wang D, Heng Y, Hou G, Zi G, Ding W, Walter MD. A Comprehensive Study Concerning the Synthesis, Structure, and Reactivity of Terminal Uranium Oxido, Sulfido, and Selenido Metallocenes. J Am Chem Soc 2023. [PMID: 37376858 DOI: 10.1021/jacs.3c03753] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/29/2023]
Abstract
Terminal uranium oxido, sulfido, and selenido metallocenes were synthesized, and their reactivity was comprehensively studied. Heating of an equimolar mixture of [η5-1,2,4-(Me3Si)3C5H2]2UMe2 (2) and [η5-1,2,4-(Me3Si)3C5H2]2U(NH-p-tolyl)2 (3) in the presence of 4-dimethylaminopyridine (dmap) in refluxing toluene forms [η5-1,2,4-(Me3Si)3C5H2]2U═N(p-tolyl)(dmap) (4), which is a useful precursor for the preparation of the terminal uranium oxido, sulfido, and selenido metallocenes [η5-1,2,4-(Me3Si)3C5H2]2U═E(dmap) (E = O (5), S (6), Se (7)) employing a cycloaddition-elimination methodology with Ph2C═E (E = O, S) or (p-MeOPh)2CSe, respectively. Metallocenes 5-7 are inert toward alkynes, but they act as nucleophiles in the presence of alkylsilyl halides. The oxido and sulfido metallocenes 5 and 6 undergo [2 + 2] cycloadditions with isothiocyanate PhNCS or CS2, while the selenido derivative 7 does not. The experimental studies are complemented by density functional theory (DFT) computations.
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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
| | - Wanjian Ding
- Department of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Marc D Walter
- Institut für Anorganische und Analytische Chemie, Technische Universitüt Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
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8
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Wilson HH, Yu X, Cheisson T, Smith PW, Pandey P, Carroll PJ, Minasian SG, Autschbach J, Schelter EJ. Synthesis and Characterization of a Bridging Cerium(IV) Nitride Complex. J Am Chem Soc 2023; 145:781-786. [PMID: 36603174 DOI: 10.1021/jacs.2c12145] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Complexes featuring lanthanide-ligand multiple bonds are rare and highly reactive. They are important synthetic targets to understand 4f/5d-bonding in comparison to d-block and actinide congeners. Herein, the isolation and characterization of a bridging cerium(IV)-nitride complex: [(TriNOx)Ce(Li2μ-N)Ce(TriNOx)][BArF4] is reported, the first example of a molecular cerium-nitride. The compound was isolated by deprotonating a monometallic cerium(IV)-ammonia complex: [CeIV(NH3)(TriNOx)][BArF4]. The average Ce═N bond length of [(TriNOx)Ce(Li2μ-N)Ce(TriNOx)][BArF4] was 2.117(3) Å. Vibrational studies of the 15N-isotopomer exhibited a shift of the Ce═N═Ce asymmetric stretch from ν = 644 cm-1 to 640 cm-1, and X-ray spectroscopic studies confirm the +4 oxidation state of cerium. Computational analyses showed strong involvement of the cerium 4f shell in bonding with overall 16% and 11% cerium weight in the σ- and π-bonds of the Ce═N═Ce fragment, respectively.
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Affiliation(s)
- Henry H Wilson
- P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
| | - Xiaojuan Yu
- Department of Chemistry, University of Buffalo, 732 Natural Sciences Complex, Buffalo, New York 14260, United States
| | - Thibault Cheisson
- P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
| | - Patrick W Smith
- Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Pragati Pandey
- P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
| | - Patrick J Carroll
- P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
| | - Stefan G Minasian
- Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Jochen Autschbach
- Department of Chemistry, University of Buffalo, 732 Natural Sciences Complex, Buffalo, New York 14260, United States
| | - Eric J Schelter
- P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
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9
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Li XB, Wu QY, Wang CZ, Lan JH, Zhang M, Gibson JK, Chai ZF, Shi WQ. Reduction of Np(VI) with hydrazinopropionitrile via water-mediated proton transfer. Phys Chem Chem Phys 2022; 24:17782-17791. [PMID: 35848639 DOI: 10.1039/d2cp01730j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Effectively adjusting and controlling the valence state of neptunium (Np) is essential in its separation during spent fuel reprocessing. Hydrazine and its derivatives as free-salts can selectively reduce Np(VI) to Np(V). Reduction mechanisms of Np(VI) with hydrazine and four derivatives have been explored using multiple theoretical methods in our previous works. Herein, we examine the reduction mechanism of Np(VI) with hydrazinopropionitrile (NCCH2N2H3) which exhibits faster kinetics than most other hydrazine derivatives probably due to its σ-π hyperconjugation effect. Free radical ion pathways I, II and III involving the three types of hydrazine H atoms were found that correspond to the experimentally established mechanism of reduction of two Np(VI) via initial oxidation to [NCCH2N2H3]+˙, followed by conversion to NCCH2N2H (+2H3O+) and ultimately to CH3CN + N2. Potential energy profiles suggest that the second redox stage is rate-determining for all three pathways. Pathway I with water-mediated proton transfer is energetically preferred for hydrazinopropionitrile. Analyses using the approaches of localized molecular orbitals (LMOs), quantum theory of atoms in molecules (QTAIM), and intrinsic reaction coordinate (IRC) elucidate the bonding evolution for the structures on the reaction pathways. The results of the spin density reveal that the reduction of the first Np(VI) ion is the outer-sphere electron transfer, while that of the second Np(VI) ion is the hydrogen transfer. This work offers new insights into the nature of reduction of Np(VI) by hydrazinopropionitrile via water-mediated proton transfer, and provides a basis for designing free-salt reductants for Np separations.
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Affiliation(s)
- Xiao-Bo Li
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China. .,Fundamental Science on Nuclear Safety and Simulation Technology Laboratory, College of Nuclear Science and Technology, Harbin Engineering University, Harbin, Heilongjiang, 150001, China
| | - Qun-Yan Wu
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.
| | - Cong-Zhi Wang
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.
| | - Jian-Hui Lan
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.
| | - Meng Zhang
- Fundamental Science on Nuclear Safety and Simulation Technology Laboratory, College of Nuclear Science and Technology, Harbin Engineering University, Harbin, Heilongjiang, 150001, China
| | - John K Gibson
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, 94720, USA
| | - Zhi-Fang Chai
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.
| | - Wei-Qun Shi
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.
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10
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Wang S, Heng Y, Li T, Wang D, Hou G, Zi G, Walter MD. Intrinsic reactivity of [η 5-1,3-(Me 3Si) 2C 5H 3] 2U(η 4-C 4Ph 2) in small molecule activation. Dalton Trans 2022; 51:11072-11085. [PMID: 35796202 DOI: 10.1039/d2dt01730j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The uranium metallacyclocumulene, [η5-1,3-(Me3Si)2C5H3]2U(η4-C4Ph2) (3) was isolated from the reaction mixture containing [η5-1,3-(Me3Si)2C5H3]2UCl2 (1), potassium graphite (KC8) and 1,4-diphenylbutadiyne (PhCC-CCPh) in good yield. The reactivity of 3 towards various small organic molecules was evaluated. For example, while complex 3 shows no reactivity towards alkynes and 2,2'-bipyridine, it may deliver the [η5-1,3-(Me3Si)2C5H3]2U(II) fragment in the presence of Ph2E2 (E = S, Se) and Ph3CN3, or react as a nucleophile in the presence of carbodiimides, isothiocyanates, aldehydes, ketones, and pyridine derivatives, forming five-, seven- or nine-membered heterometallacycles. On the contrary, addition of Ph2CS to 3 induces CS bond cleavage yielding the dithiolate complex [η5-1,3-(Me3Si)2C5H3]2U[S2(C12H5Ph5)] (14). In contrast, the closely related, but sterically more encumbered uranium metallacyclocumulene [η5-1,2,4-(Me3Si)3C5H2]2U(η4-C4Ph2) (4) features a more limited reactivity which is restricted to mono- and double insertions with small unsaturated organic molecules such as isothiocyanates, ketones and nitriles.
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Affiliation(s)
- Shichun Wang
- Department of Chemistry, Beijing Normal University, Beijing 100875, China.
| | - Yi Heng
- Department of Chemistry, Beijing Normal University, Beijing 100875, China.
| | - Tongyu Li
- 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.
| | - Marc D Walter
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany.
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11
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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: 1] [Impact Index Per Article: 0.5] [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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12
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Basappa S, Bhawar R, Nagaraju DH, Bose SK. Recent advances in the chemistry of the phosphaethynolate and arsaethynolate anions. Dalton Trans 2022; 51:3778-3806. [PMID: 35108724 DOI: 10.1039/d1dt03994f] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Over the past decade, the reactivity of 2-phosphaethynolate (OCP-), a heavier analogue of the cyanate anion, has been the subject of momentous interest in the field of modern organometallic chemistry. It is used as a precursor to novel phosphorus-containing heterocycles and as a ligand in decarbonylative processes, serving as a synthetic equivalent of a phosphinidene derivative. This perspective aims to describe advances in the reactivities of phosphaethynolate and arsaethynolate anions (OCE-; E = P, As) with main-group element, transition metal, and f-block metal scaffolds. Further, the unique structures and bonding properties are discussed based on spectroscopic and theoretical studies.
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Affiliation(s)
- Suma Basappa
- Centre for Nano and Material Sciences (CNMS), Jain University, Jain Global Campus, Bangalore-562112, India.
| | - Ramesh Bhawar
- Centre for Nano and Material Sciences (CNMS), Jain University, Jain Global Campus, Bangalore-562112, India.
| | - D H Nagaraju
- Department of Chemistry, School of Applied Sciences, Reva University, Bangalore 560064, India.
| | - Shubhankar Kumar Bose
- Centre for Nano and Material Sciences (CNMS), Jain University, Jain Global Campus, Bangalore-562112, India.
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13
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Alvarez S. Continuous Shape Measures Study of the Coordination Spheres of Actinide Complexes – Part 1: Low Coordination Numbers. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100500] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Santiago Alvarez
- Department de Química Inorgànica i Orgànica – Secció de Química Inorgànica and Institut de Química Teòrica i Computacional Universitat de Barcelona Martí i Franquès 1 08028 Barcelona Spain
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14
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Evidence for ligand- and solvent-induced disproportionation of uranium(IV). Nat Commun 2021; 12:4832. [PMID: 34376682 PMCID: PMC8355312 DOI: 10.1038/s41467-021-25151-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 07/21/2021] [Indexed: 11/08/2022] Open
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.
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15
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Wang S, Heng Y, Li T, Hou G, Zi G, Walter MD. Synthesis and reactivity of the uranium phosphinidene metallocene [η 5-1,3-(Me 3Si) 2C 5H 3] 2U([double bond, length as m-dash]P-2,4,6- iPr 3C 6H 2)(OPMe 3): influence of the coordinated Lewis base. Dalton Trans 2021; 50:12502-12516. [PMID: 34342314 DOI: 10.1039/d1dt02149d] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
This paper describes the synthesis and reactivity of [η5-1,3-(Me3Si)2C5H3]2U([double bond, length as m-dash]P-2,4,6-iPr3C6H2)(OPMe3) (6) which is accessible from a ligand exchange reaction between [η5-1,3-(Me3Si)2C5H3]2U([double bond, length as m-dash]P-2,4,6-iPr3C6H2)(OPPh3) (2) and Me3PO at ambient temperature. Phosphinidene 6 exhibits no reactivity towards internal alkynes, but readily reacts with various hetero-unsaturated molecules such as isothiocyanates, aldehydes, nitriles, isonitriles, and organic azides, forming uranium sulfido, oxido, imido, and uranaheterocyclic compounds. Nevertheless, with the bidentate ortho-dicyanobenzene o-C6H4(CN)2 the zwitterionic species [η5-1,3-(Me3Si)2C5H3]2U[NHC(N){C6H4CP(2,4,6-iPr3C6H2)CH2PMe2O}] (13) is isolated in good yield. Moreover, 6 converts with Ph2S2 to the uranium(iii) phenylthiolate compound [η5-1,3-(Me3Si)2C5H3]2USPh(OPMe3) (7) in good isolated yield. Furthermore, the influence of the Lewis base on the reactivity of the uranium phosphinidene metallocenes has also been evaluated.
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Affiliation(s)
- Shichun Wang
- Department of Chemistry, Beijing Normal University, Beijing 100875, China.
| | - Yi Heng
- Department of Chemistry, Beijing Normal University, Beijing 100875, China.
| | - Tongyu Li
- 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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16
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Wang S, Li T, Heng Y, Hou G, Zi G, Walter MD. Influence of the 1,3-Bis(trimethylsilyl)cyclopentadienyl Ligand on the Reactivity of the Uranium Phosphinidene [η5-1,3-(Me3Si)2C5H3]2U(═P-2,4,6-iPr3C6H2)(OPPh3). Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00303] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Shichun Wang
- Department of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Tongyu Li
- 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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17
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Yu J, Liu K, Wu Q, Li B, Kong X, Hu K, Mei L, Yuan L, Chai Z, Shi W. Facile Access to Uranium and Thorium Phosphaethynolate Complexes Supported by Tren: Experimental and Theoretical Study. CHINESE J CHEM 2021. [DOI: 10.1002/cjoc.202100149] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Jipan Yu
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China
| | - Kang Liu
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China
| | - Qunyan Wu
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China
| | - Bin Li
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China
| | - Xianghe Kong
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China
| | - Kongqiu Hu
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China
| | - Lei Mei
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China
| | - Liyong Yuan
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China
| | - Zhifang Chai
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China
- Engineering Laboratory of Advanced Energy Materials Institute of Industrial Technology Chinese Academy of Sciences, Ningbo Zhejiang 315201 China
| | - Weiqun Shi
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China
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18
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Revathi S, Raja P, Saha S, Eisen MS, Ghatak T. Recent developments in highly basic N-heterocyclic iminato ligands in actinide chemistry. Chem Commun (Camb) 2021; 57:5483-5502. [PMID: 34008633 DOI: 10.1039/d1cc00933h] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In the last decade, major conceptual advances in the chemistry of actinide molecules and materials have been made to demonstrate their distinct reactivity profiles as compared to lanthanide and transition metal compounds, but some difficult questions remain concerning the intriguing stability of low-valent actinide complexes, and the importance of the 5f-orbitals in reactivity and bonding. The imidazolin-2-iminato moiety has been extensively used in ligands for the advancement of actinide chemistry owing to its unique capability of stabilizing the reactive and highly electrophilic metal ions by virtue of its strong electron donation and steric tunability. The current review article describes recent developments in the chemistry of light actinide metal ions (thorium and uranium) bearing these N-heterocyclic iminato moieties as supporting ligands. In addition, the effect of ring expansion of the N-heterocycle on the catalytic aptitude of the organoactinides is also described herein. The synthesis and reactivity of actinide complexes bearing N-heterocyclic iminato ligands are presented, and promising apposite applications are also presented. The current review focuses on addressing the catalytic behavior of actinide complexes with oxygen-containing substrates such as in the Tishchenko reaction, hydroelementation processes, and polymerization reactions. Actinide complexes have also found new catalytic applications, as demonstrated by the potent chemoselective carbonyl hydroboration and tandem proton-transfer esterification (TPTE) reaction, featuring coupling between an aldehyde and alcohol.
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Affiliation(s)
- Shanmugam Revathi
- Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore-632014, Tamil Nadu, India.
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19
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Du J, Hunger D, Seed JA, Cryer JD, King DM, Wooles AJ, van Slageren J, Liddle ST. Dipnictogen f-Element Chemistry: A Diphosphorus Uranium Complex. J Am Chem Soc 2021; 143:5343-5348. [PMID: 33792307 DOI: 10.1021/jacs.1c02482] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The first isolation and structural characterization of an f-element dinitrogen complex was reported in 1988, but an f-element complex with the first heavier group 15 homologue diphosphorus has to date remained unknown. Here, we report the synthesis of a side-on bound diphosphorus complex of uranium(IV) using a 7λ3-(dimethylamino)phosphadibenzonorbornadiene-mediated P atom transfer approach. Experimental and computational characterization reveals that the diphosphorus ligand is activated to its dianionic (P2)2- form and that in-plane U-P π-bonding dominates the bonding of the U(μ-η2:η2-P2)U unit, which is supplemented by a weak U-P interaction of δ symmetry. A preliminary reactivity study demonstrates conversion of this diphosphorus complex to unprecedented uranium cyclo-P3 complexes, suggesting in situ generation of transient, reactive phosphido species.
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Affiliation(s)
- Jingzhen Du
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K
| | - David Hunger
- Institute of Physical Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - John A Seed
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K
| | - Jonathan D Cryer
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K
| | - David M King
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, U.K
| | - Ashley J Wooles
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K
| | - Joris van Slageren
- Institute of Physical Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - Stephen T Liddle
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K
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20
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Wang D, Ding W, Hou G, Zi G, Walter MD. Uranium versus Thorium: Synthesis and Reactivity of [η 5 -1,2,4-(Me 3 C) 3 C 5 H 2 ] 2 U[η 2 -C 2 Ph 2 ]. Chemistry 2021; 27:6767-6782. [PMID: 33559922 PMCID: PMC8251885 DOI: 10.1002/chem.202100089] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Indexed: 01/09/2023]
Abstract
The synthesis, electronic structure, and reactivity of a uranium metallacyclopropene were comprehensively studied. Addition of diphenylacetylene (PhC≡CPh) to the uranium phosphinidene metallocene [η5‐1,2,4‐(Me3C)3C5H2]2U=P‐2,4,6‐tBu3C6H2 (1) yields the stable uranium metallacyclopropene, [η5‐1,2,4‐(Me3C)3C5H2]2U[η2‐C2Ph2] (2). Based on density functional theory (DFT) results the 5f orbital contributions to the bonding within the metallacyclopropene U‐(η2‐C=C) moiety increases significantly compared to the related ThIV compound [η5‐1,2,4‐(Me3C)3C5H2]2Th[η2‐C2Ph2], which also results in more covalent bonds between the [η5‐1,2,4‐(Me3C)3C5H2]2U2+ and [η2‐C2Ph2]2− fragments. Although the thorium and uranium complexes are structurally closely related, different reaction patterns are therefore observed. For example, 2 reacts as a masked synthon for the low‐valent uranium(II) metallocene [η5‐1,2,4‐(Me3C)3C5H2]2UII when reacted with Ph2E2 (E=S, Se), alkynes and a variety of hetero‐unsaturated molecules such as imines, ketazine, bipy, nitriles, organic azides, and azo derivatives. In contrast, five‐membered metallaheterocycles are accessible when 2 is treated with isothiocyanate, aldehydes, and ketones.
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Affiliation(s)
- Deqiang Wang
- Department of Chemistry, Beijing Normal University, Beijing, 100875, China
| | - Wanjian Ding
- 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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21
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Du J, Balázs G, Wooles AJ, Scheer M, Liddle ST. The “Hidden” Reductive [2+2+1]‐Cycloaddition Chemistry of 2‐Phosphaethynolate Revealed by Reduction of a Th‐OCP Linkage. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202012506] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Jingzhen Du
- Department of Chemistry The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Gábor Balázs
- Institute of Inorganic Chemistry University of Regensburg Universitätsstr. 31 93053 Regensburg Germany
| | - Ashley J. Wooles
- Department of Chemistry The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Manfred Scheer
- Institute of Inorganic Chemistry University of Regensburg Universitätsstr. 31 93053 Regensburg Germany
| | - Stephen T. Liddle
- Department of Chemistry The University of Manchester Oxford Road Manchester M13 9PL UK
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22
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Du J, Balázs G, Wooles AJ, Scheer M, Liddle ST. The "Hidden" Reductive [2+2+1]-Cycloaddition Chemistry of 2-Phosphaethynolate Revealed by Reduction of a Th-OCP Linkage. Angew Chem Int Ed Engl 2021; 60:1197-1202. [PMID: 33051949 PMCID: PMC7839465 DOI: 10.1002/anie.202012506] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Indexed: 11/27/2022]
Abstract
The reduction chemistry of the newly emerging 2‐phosphaethynolate (OCP)− is not well explored, and many unanswered questions remain about this ligand in this context. We report that reduction of [Th(TrenTIPS)(OCP)] (2, TrenTIPS=[N(CH2CH2NSiPri3)]3−), with RbC8 via [2+2+1] cycloaddition, produces an unprecedented hexathorium complex [{Th(TrenTIPS)}6(μ‐OC2P3)2(μ‐OC2P3H)2Rb4] (5) featuring four five‐membered [C2P3] phosphorus heterocycles, which can be converted to a rare oxo complex [{Th(TrenTIPS)(μ‐ORb)}2] (6) and the known cyclometallated complex [Th{N(CH2CH2NSiPri3)2(CH2CH2SiPri2CHMeCH2)}] (4) by thermolysis; thereby, providing an unprecedented example of reductive cycloaddition reactivity in the chemistry of 2‐phosphaethynolate. This has permitted us to isolate intermediates that might normally remain unseen. We have debunked an erroneous assumption of a concerted fragmentation process for (OCP)−, rather than cycloaddition products that then decompose with [Th(TrenTIPS)O]− essentially acting as a protecting then leaving group. In contrast, when KC8 or CsC8 were used the phosphinidiide C−H bond activation product [{Th(TrenTIPS)}Th{N(CH2CH2NSiPri3)2[CH2CH2SiPri2CH(Me)CH2C(O)μ‐P]}] (3) and the oxo complex [{Th(TrenTIPS)(μ‐OCs)}2] (7) were isolated.
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Affiliation(s)
- Jingzhen Du
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Gábor Balázs
- Institute of Inorganic Chemistry, University of Regensburg, Universitätsstr. 31, 93053, Regensburg, Germany
| | - Ashley J Wooles
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Manfred Scheer
- Institute of Inorganic Chemistry, University of Regensburg, Universitätsstr. 31, 93053, Regensburg, Germany
| | - Stephen T Liddle
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK
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23
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Wang D, Hou G, Zi G, Walter MD. Influence of the Lewis Base Ph3PO on the Reactivity of the Uranium Phosphinidene (η5-C5Me5)2U(═P-2,4,6-iPr3C6H2)(OPPh3). Organometallics 2021. [DOI: 10.1021/acs.organomet.0c00716] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Deqiang 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
| | - Marc D. Walter
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
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24
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Li B, Yu J, Liu K, Wu Q, Liu Q, Shi W. Research Progress of Actinide-Ligand Multiple Bonding Supported by Tripodal Ligands. ACTA CHIMICA SINICA 2021. [DOI: 10.6023/a21040140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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25
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Wang D, Wang S, Li T, Heng Y, Hou G, Zi G, Walter MD. Reactivity studies involving a Lewis base supported terminal uranium phosphinidene metallocene [η5-1,3-(Me3C)2C5H3]2U(P-2,4,6-iPr3C6H2)(OPMe3). Dalton Trans 2021; 50:8349-8363. [DOI: 10.1039/d1dt00742d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Small variations in the phosphinidene substituents, but significant change the reactivity of the uranium phosphinidene complexes.
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Affiliation(s)
- Deqiang Wang
- Department of Chemistry
- Beijing Normal University
- Beijing 100875
- China
| | - Shichun Wang
- Department of Chemistry
- Beijing Normal University
- Beijing 100875
- China
| | - Tongyu Li
- 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
- 38106 Braunschweig
- Germany
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26
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Wu QY, Wang CZ, Lan JH, Chai ZF, Shi WQ. Electronic structures and bonding of the actinide halides An(TREN TIPS)X (An = Th-Pu; X = F-I): a theoretical perspective. Dalton Trans 2020; 49:15895-15902. [PMID: 33164010 DOI: 10.1039/d0dt02909b] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To evaluate how halogen and actinide atoms affect the electronic structures and bonding nature, we have theoretically investigated a series of the actinide halides An(TRENTIPS)X (An = Th-Pu; X = F-I); several of them have been synthesized by Liddle's group. The An-X bond distances decrease from An = Th to Pu for the same halides, and the harmonic vibrational frequencies for the An-X bonds are more susceptible to being affected by the halogen atoms. The analyses of bonding nature reveal that the An-X bonds have a certain covalency with a polarized character, and the σ-bonding component in the total orbital contribution is greatly larger than the corresponding π-bonding ones based on the analysis of the NOCVs (the natural orbitals for chemical valence). Furthermore, the electronic structures of the thorium complexes are obviously different from those of the uranium and transuranic analogues due to more valence electrons in Th 6d orbitals. In addition, thermodynamic results suggest that the U(TRENTIPS)Br complex is the most stable and U(TRENTIPS)Cl has the highest reactivity based on the halide exchange reaction of U(TRENTIPS)X complexes using Me3SiX. The reduction ability of the tetravalent An(TRENTIPS)X is sensitive to halogen atoms according to the calculated electron affinity of the An(TRENTIPS)X and the reactions An(TRENTIPS)X + K → An(TRENTIPS) + KX. This work presents the effect of the halogen and the actinide atoms on the structures, bonding nature and redox ability of a series of the tetravalent actinide halides with TREN ligand and facilitates our in-depth understanding of f-block elements, which could provide theoretical guidance for experimental work on actinide halides, especially for the synthetic chemistry of transuranic halides.
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Affiliation(s)
- Qun-Yan Wu
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
| | - Cong-Zhi Wang
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
| | - Jian-Hui Lan
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
| | - Zhi-Fang Chai
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China. and Engineering Laboratory of Nuclear Energy Materials, Ningbo Institute of Industrial Technology, Chinese Academy of Sciences, Ningbo, Zhejiang 315201, China
| | - Wei-Qun Shi
- Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
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27
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Wang D, Ding W, Hou G, Zi G, Walter MD. Experimental and Computational Studies on a Base-Free Terminal Uranium Phosphinidene Metallocene. Chemistry 2020; 26:16888-16899. [PMID: 32744750 PMCID: PMC7756876 DOI: 10.1002/chem.202003465] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 07/31/2020] [Indexed: 12/26/2022]
Abstract
The first stable base‐free terminal uranium phosphinidene metallocene is presented; and its structure and reactivity have been studied in detail and compared to that of the corresponding thorium derivative. Salt metathesis reaction of the methyl iodide uranium metallocene Cp’’’2U(I)Me (2, Cp’’’=η5‐1,2,4‐(Me3C)3C5H2) with Mes*PHK (Mes*=2,4,6‐(Me3C)3C6H2) in THF yields the base‐free terminal uranium phosphinidene metallocene, Cp’’’2U=PMes* (3). In addition, density functional theory (DFT) studies suggest substantial 5f orbital contributions to the bonding within the uranium phosphinidene [U]=PAr moiety, which results in a more covalent bonding between the [Cp’’’2U]2+ and [Mes*P]2− fragments than that for the related thorium derivative. This difference in bonding besides steric reasons causes different reactivity patterns for both molecules. Therefore, the uranium derivative 3 may act as a Cp’’’2U(II) synthon releasing the phosphinidene moiety (Mes*P:) when treated with alkynes or a variety of hetero‐unsaturated molecules such as imines, thiazoles, ketazines, bipy, organic azides, diazene derivatives, ketones, and carbodiimides.
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Affiliation(s)
- Deqiang Wang
- Department of Chemistry, Beijing Normal University, Beijing, 100875, China
| | - Wanjian Ding
- 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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28
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Seed JA, Sharpe HR, Futcher HJ, Wooles AJ, Liddle ST. Nature of the Arsonium‐Ylide Ph
3
As=CH
2
and a Uranium(IV) Arsonium–Carbene Complex. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202004983] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- John A. Seed
- Department of Chemistry The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Helen R. Sharpe
- Department of Chemistry The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Harry J. Futcher
- 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
| | - Stephen T. Liddle
- Department of Chemistry The University of Manchester Oxford Road Manchester M13 9PL UK
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29
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Cobb PJ, Wooles AJ, Liddle ST. A Uranium(VI)-Oxo-Imido Dimer Complex Derived from a Sterically Demanding Triamidoamine. Inorg Chem 2020; 59:10034-10041. [PMID: 32602709 DOI: 10.1021/acs.inorgchem.0c01207] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The reaction of [UO2(μ-Cl)4{K(18-crown-6)}2] with [{N(CH2CH2NSiPri3)3}Li3] gives [{UO(μ-NCH2CH2N[CH2CH2NSiPri3]2)}2] (1), [{(LiCl)(KCl)(18-crown-6)}2] (2), and [LiOSiPri3] (3) in a 1:2:2 ratio. The formation of the oxo-imido 1 involves the cleavage of a N-Si bond and the activation of one of the usually robust U═O bonds of uranyl(VI), resulting in the formation of uranium(VI)-imido and siloxide linkages. Notably, the uranium oxidation state remains unchanged at +6 in the starting material and product. Structural characterization suggests the dominance of a core RN═U═O group, and the dimeric formulation of 1 is supported by bridging imido linkages in a highly asymmetric U2N2 ring. Density functional theory analyses find a σ > π orbital energy ordering for the U═N and U═O bonds in 1, which is uranyl-like in nature. Complexes 1-3 were characterized variously by single crystal X-ray diffraction, multinuclear NMR, IR, Raman, and optical spectroscopies; cyclic voltammetry; and density functional theory.
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Affiliation(s)
- Philip J Cobb
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Ashley J Wooles
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Stephen T Liddle
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
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30
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Seed JA, Sharpe HR, Futcher HJ, Wooles AJ, Liddle ST. Nature of the Arsonium-Ylide Ph 3 As=CH 2 and a Uranium(IV) Arsonium-Carbene Complex. Angew Chem Int Ed Engl 2020; 59:15870-15874. [PMID: 32484980 DOI: 10.1002/anie.202004983] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 05/28/2020] [Indexed: 11/11/2022]
Abstract
Treatment of [Ph3 EMe][I] with [Na{N(SiMe3 )2 }] affords the ylides [Ph3 E=CH2 ] (E=As, 1As; P, 1P). For 1As this overcomes prior difficulties in the synthesis of this classical arsonium-ylide that have historically impeded its wider study. The structure of 1As has now been determined, 45 years after it was first convincingly isolated, and compared to 1P, confirming the long-proposed hypothesis of increasing pyramidalisation of the ylide-carbon, highlighting the increasing dominance of E+ -C- dipolar resonance form (sp3 -C) over the E=C ene π-bonded form (sp2 -C), as group 15 is descended. The uranium(IV)-cyclometallate complex [U{N(CH2 CH2 NSiPri 3 )2 (CH2 CH2 SiPri 2 CH(Me)CH2 )}] reacts with 1As and 1P by α-proton abstraction to give [U(TrenTIPS )(CHEPh3 )] (TrenTIPS =N(CH2 CH2 NSiPri 3 )3 ; E=As, 2As; P, 2P), where 2As is an unprecedented structurally characterised arsonium-carbene complex. The short U-C distances and obtuse U-C-E angles suggest significant U=C double bond character. A shorter U-C distance is found for 2As than 2P, consistent with increased uranium- and reduced pnictonium-stabilisation of the carbene as group 15 is descended, which is supported by quantum chemical calculations.
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Affiliation(s)
- John A Seed
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Helen R Sharpe
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Harry J Futcher
- 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
| | - Stephen T Liddle
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK
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31
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Boreen MA, Gould CA, Booth CH, Hohloch S, Arnold J. Structure and magnetism of a tetrahedral uranium(iii) β-diketiminate complex. Dalton Trans 2020; 49:7938-7944. [PMID: 32495782 DOI: 10.1039/d0dt01599g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We describe the functionalisation of the previously reported uranium(iii) β-diketiminate complex (BDI)UI2(THF)2 (1) with one and two equivalents of a sterically demanding 2,6-diisopropylphenolate ligand (ODipp) leading to the formation of two heteroleptic complexes: [(BDI)UI(ODipp)]2 (2) and (BDI)U(ODipp)2 (3). The latter is a rare example of a tetrahedral uranium(iii) complex, and it shows single-molecule magnet behaviour.
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Affiliation(s)
- Michael A Boreen
- Department of Chemistry, University of California, Berkeley, California 94720, USA.
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32
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Ghorai S, Jemmis ED. Structures and bonding in [L]M(μ-CCR) 2M[L] and [L]M(μ-RC 4R)M[L]: requirements for C-C coupling. Dalton Trans 2020; 49:5157-5166. [PMID: 32236179 DOI: 10.1039/c9dt04748d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A theoretical analysis of [L]M(μ-CCR)2M[L] and [L]M(μ-RC4R)M[L], where M represents the selected elements from the main group, transition metals, lanthanides and actinides, shows how the central (μ-CCR)2 and (μ-RC4R) units reorganize as M traverses across the periodic table. In this context transition metal and actinide complexes are similar in nature, while lanthanide and main group complexes show similarity. The ground state electronic configuration and thus the metal oxidation state control these striking differences. An effective way to stabilize the (iii) oxidation state of thorium in a metallacycle complex is shown for the first time. A strategy is proposed to make a cross-connection between the two sets. The approach used here lends itself to obvious extensions.
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Affiliation(s)
- Sagar Ghorai
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, Karnataka, India.
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33
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Terminal uranium(V)-nitride hydrogenations involving direct addition or Frustrated Lewis Pair mechanisms. Nat Commun 2020; 11:337. [PMID: 31953390 PMCID: PMC6969212 DOI: 10.1038/s41467-019-14221-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 12/09/2019] [Indexed: 12/03/2022] Open
Abstract
Despite their importance as mechanistic models for heterogeneous Haber Bosch ammonia synthesis from dinitrogen and dihydrogen, homogeneous molecular terminal metal-nitrides are notoriously unreactive towards dihydrogen, and only a few electron-rich, low-coordinate variants demonstrate any hydrogenolysis chemistry. Here, we report hydrogenolysis of a terminal uranium(V)-nitride under mild conditions even though it is electron-poor and not low-coordinate. Two divergent hydrogenolysis mechanisms are found; direct 1,2-dihydrogen addition across the uranium(V)-nitride then H-atom 1,1-migratory insertion to give a uranium(III)-amide, or with trimesitylborane a Frustrated Lewis Pair (FLP) route that produces a uranium(IV)-amide with sacrificial trimesitylborane radical anion. An isostructural uranium(VI)-nitride is inert to hydrogenolysis, suggesting the 5f1 electron of the uranium(V)-nitride is not purely non-bonding. Further FLP reactivity between the uranium(IV)-amide, dihydrogen, and triphenylborane is suggested by the formation of ammonia-triphenylborane. A reactivity cycle for ammonia synthesis is demonstrated, and this work establishes a unique marriage of actinide and FLP chemistries. Despite their importance as mechanistic models for Haber Bosch ammonia synthesis from N2 and H2, high oxidation state terminal metal-nitrides are notoriously unreactive towards H2. Here, the authors report hydrogenolysis of a uranium(V)-nitride, which can occur directly or by Frustrated Lewis Pair chemistry with a borane ancillary.
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34
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Thorium-nitrogen multiple bonds provide evidence for pushing-from-below for early actinides. Nat Commun 2019; 10:4203. [PMID: 31519900 PMCID: PMC6744569 DOI: 10.1038/s41467-019-12206-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 08/08/2019] [Indexed: 12/31/2022] Open
Abstract
Although the chemistry of uranium-ligand multiple bonding is burgeoning, analogous complexes involving other actinides such as thorium remain rare and there are not yet any terminal thorium nitrides outside of cryogenic matrix isolation conditions. Here, we report evidence that reduction of a thorium-azide produces a transient Th≡N triple bond, but this activates C-H bonds to produce isolable parent imido derivatives or it can be trapped in an N-heterocycle amine. Computational studies on these thorium-nitrogen multiple bonds consistently evidences a σ > π energy ordering. This suggests pushing-from-below for thorium, where 6p-orbitals principally interact with filled f-orbitals raising the σ-bond energy. Previously this was dismissed for thorium, being the preserve of uranium-nitrides or the uranyl dication. Recognising that pushing-from-below perhaps occurs with thorium as well as uranium, and with imido ligands as well as nitrides, suggests this phenomenon may be more widespread than previously thought. Despite the burgeoning nature of uranium–ligand multiple bonding, analogous thorium complexes remain incredibly rare. Here the authors report evidence for a transient thorium–nitride species, which, together with data on parent imido derivatives, suggests that the pushing-from-below phenomenon may be more widespread than previously thought.
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35
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Rao G, Altman AB, Brown AC, Tao L, Stich TA, Arnold J, Britt RD. Metal Bonding with 3d and 6d Orbitals: An EPR and ENDOR Spectroscopic Investigation of Ti 3+-Al and Th 3+-Al Heterobimetallic Complexes. Inorg Chem 2019; 58:7978-7988. [PMID: 31185562 PMCID: PMC6584900 DOI: 10.1021/acs.inorgchem.9b00720] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Accessing covalent
bonding interactions between actinides and ligating atoms remains
a central problem in the field. Our current understanding of actinide
bonding is limited because of a paucity of diverse classes of compounds
and the lack of established models. We recently synthesized a thorium
(Th)–aluminum (Al) heterobimetallic molecule that represents
a new class of low-valent Th-containing compounds. To gain further
insight into this system and actinide–metal bonding more generally,
it is useful to study their underlying electronic structures. Here,
we report characterization by electron paramagnetic resonance (EPR)
and electron–nuclear double resonance (ENDOR) spectroscopy
of two heterobimetallic compounds: (i) a Cptt2ThH3AlCTMS3 [TMS = Si(CH3)3; Cptt = 1,3-di-tert-butylcyclopentadienyl]
complex with bridging hydrides and (ii) an actinide-free Cp2TiH3AlCTMS3 (Cp = cyclopentadienyl) analogue.
Analyses of the hyperfine interactions between the paramagnetic trivalent
metal centers and the surrounding magnetic nuclei, 1H and 27Al, yield spin distributions over both complexes. These results
show that while the bridging hydrides in the two complexes have similar
hyperfine couplings (aiso = −9.7
and −10.7 MHz, respectively), the spin density on the Al ion
in the Th3+ complex is ∼5-fold larger than that
in the titanium(3+) (Ti3+) analogue. This suggests a direct
orbital overlap between Th and Al, leading to a covalent interaction
between Th and Al. Our quantitative investigation by a pulse EPR technique
deepens our understanding of actinide bonding to main-group elements. The electronic structures of Ti3+−Al and Th3+−Al heterobimetallic complexes are probed by electron−nuclear
double resonance spectroscopy, revealing a much larger spin density
on the Al center in the latter and the presence of a covalent Th−Al
bonding interaction caused by the direct orbital overlap between Th
and Al.
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Affiliation(s)
- Guodong Rao
- Department of Chemistry , University of California at Davis , Davis , California 95616 , United States
| | - Alison B Altman
- Department of Chemistry , University of California at Berkeley , Berkeley , California 94720 , United States
| | - Alexandra C Brown
- Department of Chemistry , University of California at Berkeley , Berkeley , California 94720 , United States
| | - Lizhi Tao
- Department of Chemistry , University of California at Davis , Davis , California 95616 , United States
| | - Troy A Stich
- Department of Chemistry , University of California at Davis , Davis , California 95616 , United States
| | - John Arnold
- Department of Chemistry , University of California at Berkeley , Berkeley , California 94720 , United States
| | - R David Britt
- Department of Chemistry , University of California at Davis , Davis , California 95616 , United States
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36
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Zhang C, Hou G, Zi G, Ding W, Walter MD. An Alkali-Metal Halide-Bridged Actinide Phosphinidiide Complex. Inorg Chem 2019; 58:1571-1590. [DOI: 10.1021/acs.inorgchem.8b03091] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Congcong Zhang
- 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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37
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Zhang C, Wang Y, Hou G, Ding W, Zi G, Walter MD. Experimental and computational studies on a three-membered diphosphido thorium metallaheterocycle [η5-1,3-(Me3C)2C5H3]2Th[η2-P2(2,4,6-iPr3C6H2)2]. Dalton Trans 2019; 48:6921-6930. [DOI: 10.1039/c9dt01160a] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A three-membered diphosphido thorium metallaheterocycle complex was prepared and its reactivity was investigated.
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Affiliation(s)
- Congcong Zhang
- Department of Chemistry
- Beijing Normal University
- Beijing 100875
- China
| | - Yongsong Wang
- Department of Chemistry
- Beijing Normal University
- Beijing 100875
- China
| | - Guohua Hou
- Department of Chemistry
- Beijing Normal University
- Beijing 100875
- China
| | - Wanjian Ding
- 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
- 38106 Braunschweig
- Germany
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38
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Wang Y, Zhang C, Zi G, Ding W, Walter MD. Preparation of a potassium chloride bridged thorium phosphinidiide complex and its reactivity towards small organic molecules. NEW J CHEM 2019. [DOI: 10.1039/c9nj02269d] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The steric and electronic properties of the coordinated ligands modulate the reactivity of thorium phosphinidene complexes.
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Affiliation(s)
- Yongsong Wang
- Department of Chemistry
- Beijing Normal University
- Beijing 100875
- China
| | - Congcong Zhang
- 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
- Braunschweig
- Germany
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39
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Zhang C, Hou G, Zi G, Walter MD. A base-free terminal thorium phosphinidene metallocene and its reactivity toward selected organic molecules. Dalton Trans 2019; 48:2377-2387. [DOI: 10.1039/c9dt00012g] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Small molecule activation mediated by a base-free terminal phosphinidene thorium metallocene is reported.
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Affiliation(s)
- Congcong Zhang
- 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
- 38106 Braunschweig
- Germany
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40
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Ayres AJ, Zegke M, Ostrowski JPA, Tuna F, McInnes EJL, Wooles AJ, Liddle ST. Actinide-transition metal bonding in heterobimetallic uranium- and thorium-molybdenum paddlewheel complexes. Chem Commun (Camb) 2018; 54:13515-13518. [PMID: 30431026 DOI: 10.1039/c8cc05268a] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report the preparation of four heterobimetallic uranium- and thorium-molybdenum paddlewheel complexes. The characterisation data suggest the presence of Mo → An σ-interactions in all cases. These complexes represent unprecedented actinide-group 6 metal-metal bonds, where before heterobimetallic uranium-metal bonds were restricted to group 7-11 metals.
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Affiliation(s)
- Alexander J Ayres
- School of Chemistry, The University of Nottingham, University Park, Nottingham, NG7 2RD, UK
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41
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Zhang C, Hou G, Zi G, Ding W, Walter MD. A Base-Free Terminal Actinide Phosphinidene Metallocene: Synthesis, Structure, Reactivity, and Computational Studies. J Am Chem Soc 2018; 140:14511-14525. [DOI: 10.1021/jacs.8b09746] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Congcong Zhang
- 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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42
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Talbi-Ingrachen F, Talbi F, Kias F, Elkechai A, Boucekkine A, Daul C. DFT investigation of methane metathesis with L2AnCH3 actinide complexes catalysts (L = Cl, Cp, Cp*; An = Ac, Th, Pa, U, Np, Pu). COMPUT THEOR CHEM 2018. [DOI: 10.1016/j.comptc.2018.06.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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43
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Abstract
All-carbon metallacycles of the d-transition metals have received widespread attention over the past three decades because of their exceptional intrinsic reactivity. However, in recent years, significant progress has also been made in the synthesis and characterization of actinide metallacyclopropenes, metallacyclopentadienes, and metallacyclocumulenes (metallacyclopentatrienes). Such actinide metallacycles are of interest because of their unique structural properties, their potential application in novel group transfer reactions and catalysis, as well as their ability to engage the 5f orbitals in metal-ligand bonding. This short review summarizes the latest developments in this area focusing on all-carbon actinide metallacycles, i.e., metallacyclopropenes, metallacyclopentadienes, and metallacyclocumulenes (metallacyclopentatrienes).
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Affiliation(s)
- Guofu Zi
- Department of Chemistry, Beijing Normal University, Beijing 100875, China.
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44
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Altman AB, Brown AC, Rao G, Lohrey TD, Britt RD, Maron L, Minasian SG, Shuh DK, Arnold J. Chemical structure and bonding in a thorium(iii)-aluminum heterobimetallic complex. Chem Sci 2018; 9:4317-4324. [PMID: 29780563 PMCID: PMC5944380 DOI: 10.1039/c8sc01260a] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2018] [Accepted: 04/13/2018] [Indexed: 11/27/2022] Open
Abstract
We describe the syntheses of [Th(iii)]–[Al] and [U(iii)]–[Al] bimetallics that demonstrate An→Al interactions where the actinide behaves as an electron donor.
Thorium sits at a unique position on the periodic table. On one hand, there is little evidence that its 5f orbitals engage in bonding as they do in other early actinides; on the other hand, its chemistry is distinct from Lewis acidic transition metals. To gain insight into the underlying electronic structure of Th and develop trends across the actinide series, it is useful to study Th(iii) and Th(ii) systems with valence electrons that may engage in non-electrostatic metal–ligand interactions, although only a handful of such systems are known. To expand the range of low-valent compounds and gain deeper insight into Th electronic structure, we targeted actinide bimetallic complexes containing metal–metal bonds. Herein, we report the syntheses of Th–Al bimetallics from reactions between a di-tert-butylcyclopentadienyl supported Th(iv) dihalide (Cp‡2ThCl2) and an anionic aluminum hydride salt [K(H3AlC(SiMe3)3) (1)]. Reduction of the [Th(iv)](Cl)–[Al] product resulted in a [Th(iii)]–[Al] complex [Cp‡2Th(μ-H3)AlC(SiMe3)3 (4)]. The U(iii) analogue [Cp‡2U(μ-H3)AlC(SiMe3)3 (5)] could be synthesized directly from a U(iii) halide starting material. Electron paramagnetic resonance studies on 4 demonstrate hyperfine interactions between the unpaired electron and the Al atom indicative of spin density delocalization from the Th metal center to the Al. Density functional theory and atom in molecules calculations confirmed the presence of An→Al interactions in 4 and 5, which represents the first examples of An→M interactions where the actinide behaves as an electron donor.
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Affiliation(s)
- Alison B Altman
- Department of Chemistry , University of California , Berkeley , California 94720 , USA.,Chemical Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , USA .
| | - Alexandra C Brown
- Department of Chemistry , University of California , Berkeley , California 94720 , USA
| | - Guodong Rao
- Department of Chemistry , University of California , Davis , California 95616 , USA
| | - Trevor D Lohrey
- Department of Chemistry , University of California , Berkeley , California 94720 , USA.,Chemical Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , USA .
| | - R David Britt
- Department of Chemistry , University of California , Davis , California 95616 , USA
| | - Laurent Maron
- LPCNO , Université de Toulouse , INAS Toulouse , 135 Avenue de Rangueil , 31077 , Toulouse , France
| | - Stefan G Minasian
- Chemical Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , USA .
| | - David K Shuh
- Chemical Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , USA .
| | - John Arnold
- Department of Chemistry , University of California , Berkeley , California 94720 , USA.,Chemical Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , USA .
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Settineri NS, Arnold J. Insertion, protonolysis and photolysis reactivity of a thorium monoalkyl amidinate complex. Chem Sci 2018; 9:2831-2841. [PMID: 29732069 PMCID: PMC5914426 DOI: 10.1039/c7sc05328b] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Accepted: 02/09/2018] [Indexed: 11/21/2022] Open
Abstract
The reactivity of the thorium monoalkyl complex Th(CH2SiMe3)(BIMA)3 [1, BIMA = MeC(NiPr)2] with various small molecules is described. While steric congestion prohibits the insertion of N,N'-diisopropylcarbodiimide into the Th-C bond in 1, the first thorium tetrakis(amidinate) complex, Th(BIMA)4 (2), is synthesized via an alternative salt metathesis route. Insertion of p-tolyl azide leads to the triazenido complex Th[(p-tolyl)NNN(CH2SiMe3)-κ2N1,2](BIMA)3 (3), which then undergoes thermal decomposition to the amido species Th[(p-tolyl)N(SiMe3)](BIMA)3 (4). The reaction of 1 with 2,6-dimethylphenylisocyanide results in the thorium iminoacyl complex Th[η2-(C[double bond, length as m-dash]N)-2,6-Me2-C6H3(CH2SiMe3)](BIMA)3 (5), while the reaction with isoelectronic CO leads to the products Th[OC([double bond, length as m-dash]CH2)SiMe3](BIMA)3 (6) and Th[OC(NiPr)C(CH2SiMe3)(C(Me)N(iPr))O-κ2O,O'](BIMA)2 (7), the latter being the result of CO coupling and insertion into an amidinate ligand. Protonolysis is achieved with several substrates, producing amido (9), aryloxide (10), phosphido (11a,b), acetylide (12), and cationic (13) complexes. Ligand exchange with 9-borabicyclo[3.3.1]nonane (9-BBN) results in formation of the thorium borohydride complex (BIMA)3Th(μ-H)2[B(C8H14)] (14). Complex 1 also reacts under photolytic conditions to eliminate SiMe4 and produce Th(BIMA)2(BIMA*) [15, BIMA* = (iPr)NC(CH2)N(iPr)], featuring a rare example of a dianionic amidinate ligand. Complexes 2, 3, 5, 6, 11a, and 12-15 were characterized by 1H and 13C{1H} NMR spectroscopy, FTIR, EA, melting point and X-ray crystallography. All other complexes were identified by one or more of these spectroscopic techniques.
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Affiliation(s)
- Nicholas S Settineri
- Department of Chemistry , University of California , Berkeley , California 94720 , USA .
- Chemical Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , USA
| | - John Arnold
- Department of Chemistry , University of California , Berkeley , California 94720 , USA .
- Chemical Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , USA
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46
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Paparo A, van Krüchten FD, Spaniol TP, Okuda J. Formate complexes of titanium(iv) supported by a triamido-amine ligand. Dalton Trans 2018; 47:3530-3537. [PMID: 29431800 DOI: 10.1039/c7dt04859a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The terminal formate complex [(OCHO)Ti(N3N)] (3) containing the trianionic triamido-amine ligand (Me3SiNCH2CH2)3N3- (N3N) was prepared via salt metathesis of [ClTi(N3N)] (1) with sodium formate or alternatively by treatment of the alkyl complex [nBuTi(N3N)] (2) with ammonium formate [HNEt3][OCHO]. Deprotonation of 3 with potassium hexamethyldisilazide gave a polymeric helical chain of the oxo complex {K[OTi(N3N)]}n (4). Reaction of 2 with the trityl salt [Ph3C][B(3,5-Cl2C6H3)4] or the Brønsted acid [HNEt3][B(C6F5)4] gave [(Et2O)Ti(N3N)][BR4] (6[BR4]·Et2O) with R = 3,5-Cl2C6H3 or C6F5. The diethyl ether ligand was easily replaced by other L-type donor ligands such as tetrahydrofuran, pyridine, and 4-dimethylaminopyridine to give 6[BR4]·L with L = thf, py, and dmap. Reaction of 6[BR4]·Et2O with a stoichiometric amount of CO2 gave the dimeric, dicationic bis(carbamate)-bridged complexes [Ti{N(CH2CH2NSiMe3)2(CH2CH2NSiMe3(μ-CO2-ηO:ηO'))}]2[BR4]2 (7[BR4]2) through insertion of one CO2 into one of the titanium-amido bonds. Addition of pyridine to 7[B(C6F5)4]2 formed the monomeric carbamate complex [(py)Ti{((O2C-κ2O,O')NSiMe3CH2CH2)N(CH2CH2NSiMe3)2}][B(C6F5)4] (8[B(C6F5)4]·py). The cationic formate-bridged species [(Ti(N3N))2(μ-OCHO-ηO:ηO')][BR4] (10[BR4]) readily formed when the terminal formate complex 3 was reacted with the cationic 6[BR4]. The reactivity of triamido-amine stabilized titanium(iv) complexes is shown to differ considerably from that of related titanium tris(anilide) complexes.
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Affiliation(s)
- A Paparo
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen, Germany.
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Hohloch S, Garner ME, Parker BF, Arnold J. New supporting ligands in actinide chemistry: tetramethyltetraazaannulene complexes with thorium and uranium. Dalton Trans 2018; 46:13768-13782. [PMID: 28959804 DOI: 10.1039/c7dt02682j] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
We report the synthesis, characterization, and preliminary reactivity of new heteroleptic thorium and uranium complexes supported by the macrocyclic TMTAA ligand (TMTAA = Tetramethyl-tetra-aza-annulene). The dihalide complexes Th(TMTAA)Cl2(THF)2 (1), [UCl2(TMTAA)]2 (2) and U(TMTAA)I2 (3) are further functionalized to the Cp* derivatives ThCp*(TMTAA)Cl (4), UCp*(TMTAA)Cl (5) and UCp*(TMTAA)I (6) (Cp* = pentamethylcyclopentadienide). Compounds 4-6 are also obtained through a one-pot reaction from standard thorium(iv) and uranium(iv) starting materials, Li2TMTAA and KCp*. Complexes 1-6 function as valuable starting materials for salt metathesis chemistry. Treatment of precursors 4 or 5 with trimethylsilylmethyllithium (LiCH2TMS) results in the new actinide TMTAA alkyl complexes ThCp*(TMTAA)(CH2TMS) (7) and UCp*(TMTAA)(CH2TMTS) (8), respectively. The TMTAA-derived alkyl complexes (7 and 8) show unexpected stability and are stable for several weeks at room temperature in solution and in the solid-state. Additionally, double substitution of the halide ligands in 1-3 shows a strong dependence on the nucleophile used. While weaker nucleophiles, such as amides, and more sterically demanding nucleophiles, such as Cp (Cp = cyclopenadienide), favour the formation of bis-TMTAA "sandwich" complexes [An(TMTAA)2] (An = Th (9) and An = U (10)), the use of oxygen-functionalized ligands like the ODipp anion (Dipp = diisopropylphenyl) results in the formation of the doubly substituted species Th(ODipp)2TMTAA (11) and U(ODipp)2TMTAA (12). We also describe the divergent reactivity of the TMTAA ligand towards uranium(iii). Unlike the syntheses of actinide(iv) TMTAA complexes, the synthesis of a uranium(iii) TMTAA was not successful and only uranium(iv) species could be obtained.
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Affiliation(s)
- Stephan Hohloch
- Department of Chemistry, University of California, Berkeley, CA 94720, USA
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48
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NMR spectroscopic study of the adduct formation and reactivity of homoleptic rare earth amides with alkali metal benzyl compounds, and the crystal structures of [Li(TMEDA)2][Nd{N(SiMe3)2}3(CH2Ph)] and [{Li(TMP)}2{Li(Ph)}]2. J Organomet Chem 2018. [DOI: 10.1016/j.jorganchem.2017.10.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Rookes TM, Wildman EP, Balázs G, Gardner BM, Wooles AJ, Gregson M, Tuna F, Scheer M, Liddle ST. Actinide-Pnictide (An-Pn) Bonds Spanning Non-Metal, Metalloid, and Metal Combinations (An=U, Th; Pn=P, As, Sb, Bi). Angew Chem Int Ed Engl 2018; 57:1332-1336. [PMID: 29232498 PMCID: PMC5814731 DOI: 10.1002/anie.201711824] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Indexed: 12/03/2022]
Abstract
The synthesis and characterisation is presented of the compounds [An(TrenDMBS ){Pn(SiMe3 )2 }] and [An(TrenTIPS ){Pn(SiMe3 )2 }] [TrenDMBS =N(CH2 CH2 NSiMe2 But )3 , An=U, Pn=P, As, Sb, Bi; An=Th, Pn=P, As; TrenTIPS =N(CH2 CH2 NSiPri3 )3 , An=U, Pn=P, As, Sb; An=Th, Pn=P, As, Sb]. The U-Sb and Th-Sb moieties are unprecedented examples of any kind of An-Sb molecular bond, and the U-Bi bond is the first two-centre-two-electron (2c-2e) one. The Th-Bi combination was too unstable to isolate, underscoring the fragility of these linkages. However, the U-Bi complex is the heaviest 2c-2e pairing of two elements involving an actinide on a macroscopic scale under ambient conditions, and this is exceeded only by An-An pairings prepared under cryogenic matrix isolation conditions. Thermolysis and photolysis experiments suggest that the U-Pn bonds degrade by homolytic bond cleavage, whereas the more redox-robust thorium compounds engage in an acid-base/dehydrocoupling route.
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Affiliation(s)
- Thomas M. Rookes
- School of ChemistryThe University of ManchesterOxford RoadManchesterM13 9PLUK
| | | | - Gábor Balázs
- Institute of Inorganic ChemistryUniversity of RegensburgUniversitätsstr.3193053RegensburgGermany
| | - Benedict M. Gardner
- School of ChemistryThe University of ManchesterOxford RoadManchesterM13 9PLUK
| | - Ashley J. Wooles
- School of ChemistryThe University of ManchesterOxford RoadManchesterM13 9PLUK
| | - Matthew Gregson
- School of ChemistryThe University of ManchesterOxford RoadManchesterM13 9PLUK
| | - Floriana Tuna
- School of ChemistryThe University of ManchesterOxford RoadManchesterM13 9PLUK
| | - Manfred Scheer
- Institute of Inorganic ChemistryUniversity of RegensburgUniversitätsstr.3193053RegensburgGermany
| | - Stephen T. Liddle
- School of ChemistryThe University of ManchesterOxford RoadManchesterM13 9PLUK
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50
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Rookes TM, Wildman EP, Balázs G, Gardner BM, Wooles AJ, Gregson M, Tuna F, Scheer M, Liddle ST. Actinide-Pnictide (An−Pn) Bonds Spanning Non-Metal, Metalloid, and Metal Combinations (An=U, Th; Pn=P, As, Sb, Bi). Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201711824] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Thomas M. Rookes
- School of Chemistry; The University of Manchester; Oxford Road Manchester M13 9PL UK
| | - Elizabeth P. Wildman
- School of Chemistry; The University of Manchester; Oxford Road Manchester M13 9PL UK
| | - Gábor Balázs
- Institute of Inorganic Chemistry; University of Regensburg; Universitätsstr.31 93053 Regensburg Germany
| | - Benedict M. Gardner
- School of Chemistry; The University of Manchester; Oxford Road Manchester M13 9PL UK
| | - Ashley J. Wooles
- School of Chemistry; The University of Manchester; Oxford Road Manchester M13 9PL UK
| | - Matthew Gregson
- School of Chemistry; The University of Manchester; Oxford Road Manchester M13 9PL UK
| | - Floriana Tuna
- School of Chemistry; The University of Manchester; Oxford Road Manchester M13 9PL UK
| | - Manfred Scheer
- Institute of Inorganic Chemistry; University of Regensburg; Universitätsstr.31 93053 Regensburg Germany
| | - Stephen T. Liddle
- School of Chemistry; The University of Manchester; Oxford Road Manchester M13 9PL UK
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