1
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Modder DK, Scopelliti R, Mazzanti M. Accessing a Highly Reducing Uranium(III) Complex through Cyclometalation. Inorg Chem 2024; 63:9527-9538. [PMID: 38217471 DOI: 10.1021/acs.inorgchem.3c03668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2024]
Abstract
U(IV) cyclometalated complexes have shown rich reactivity, but their low oxidation state analogues still remain rare. Herein, we report the isolation of [K(2.2.2-cryptand)][UIII{N(SiMe3)2}2(κ2-C,N-CH2SiMe2NSiMe3)], 1, from the reduction of [UIII{N(SiMe)2}3] with KC8 and 2.2.2-cryptand at room temperature. Cyclic voltammetry studies demonstrate that 1 has a reduction potential similar to that of the previously reported [K(2.2.2-cryptand)][UII{N(SiMe)2}3] (Epc = -2.6 V versus Fc+/0 and Epc = -2.8 V versus Fc+/0, respectively). Complex 1, indeed, shows similar reducing abilities upon reactions with 4,4'-bipyridine, 2,2'-bipyridine, and 1-azidoadamantane. Interestingly, 1 was also found to be the first example of a mononuclear U(III) complex that is capable of reducing pyridine. In addition, it is shown that a wide variety of substrates can be inserted into the U-C bond, forming new U(III) metallacycles. These results highlight that cyclometalated U(III) complexes can serve as versatile precursors for a broad range of reactivity and for assembling a variety of novel chemical architectures.
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Affiliation(s)
- Dieuwertje K Modder
- Group of Coordination Chemistry, Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Rosario Scopelliti
- Group of Coordination Chemistry, Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Marinella Mazzanti
- Group of Coordination Chemistry, Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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2
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Fang W, Li Y, Zhang T, Rajeshkumar T, Del Rosal I, Zhao Y, Wang T, Wang S, Maron L, Zhu C. Oxidative Addition of E-H (E=C, N) Bonds to Transient Uranium(II) Centers. Angew Chem Int Ed Engl 2024:e202407339. [PMID: 38714494 DOI: 10.1002/anie.202407339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 05/06/2024] [Accepted: 05/07/2024] [Indexed: 05/10/2024]
Abstract
Two-electron oxidative addition is one of the most important elementary reactions for d-block transition metals but it is uncommon for f-block elements. Here, we report the first examples of intermolecular oxidative addition of E-H (E=C, N) bonds to uranium(II) centers. The transient U(II) species was formed in-situ by reducing a heterometallic cluster featuring U(IV)-Pd(0) bonds with potassium-graphite (KC8). Oxidative addition of C-H or N-H bonds to the U(II) centers was observed when this transient U(II) species was treated with benzene, carbazole or 1-adamantylamine, respectively. The U(II) centers could also react with tetracene, biphenylene or N2O, leading to the formation of arene reduced U(IV) products and uranyl(VI) species via two- or four-electron processes. This study demonstrates that the intermolecular two-electron oxidative addition reactions are viable for actinide elements.
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Affiliation(s)
- Wei Fang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Yafei Li
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Tianze Zhang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Thayalan Rajeshkumar
- LPCNO, CNRS & INSA, Université Paul Sabatier, 135 Avenue de Rangueil, 31077, Toulouse, France
| | - Iker Del Rosal
- LPCNO, CNRS & INSA, Université Paul Sabatier, 135 Avenue de Rangueil, 31077, Toulouse, France
| | - Yue Zhao
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Tianwei Wang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Shuao Wang
- State Key Laboratory of Radiation Medicine and Protection, School for Radiological and interdisciplinary Sciences (RAD-X), Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, China
| | - Laurent Maron
- LPCNO, CNRS & INSA, Université Paul Sabatier, 135 Avenue de Rangueil, 31077, Toulouse, France
| | - Congqing Zhu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
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3
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Wang S, Wang D, Heng Y, Li T, Ding W, Zi G, Walter MD. Synthesis and Structure of [η 5-1,2,4-(Me 3Si) 3C 5H 2] 2Th(bipy) and Its Reactivity toward Small Molecules. Inorg Chem 2024; 63:7473-7492. [PMID: 38591749 DOI: 10.1021/acs.inorgchem.4c00635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
Halide exchange of (Cp3tms)2ThCl2 (1; Cp3tms = η5-1,2,4-(Me3Si)3C5H2) with Me3SiI furnishes (Cp3tms)2ThI2 (2), which is then reduced with potassium graphite (KC8) in the presence of 2,2'-bipyridine to give the thorium bipyridyl metallocene (Cp3tms)2Th(bipy) (3) in good yield. Complex 3 was fully characterized and readily reacted with various small molecules. For example, 3 may serve as a synthetic equivalent for the (Cp3tms)2Th(II) fragment when exposed to CuI, Ph2S2, organic azides, and CS2. Moreover, upon the addition of thiobenzophenone Ph2CS, p-methylbenzaldehyde (p-MeC6H4)CHO, benzophenone Ph2CO, amidate PhCONH(p-tolyl), seleno-ketone (p,p'-dimethoxy), selenobenzophenone (p-MeOPh)2CSe, di(p-tolyl)methanimine (p-tolyl)2C═NH, 1,2-di(benzylidene)hydrazine (PhCH═N)2, and nitriles PhCN, PhCH2CN, and Ph2CHCN C-C coupling results to give (Cp3tms)2Th[(bipy)(Ph2CS)] (8), (Cp3tms)2Th[(bipy)(p-MePhCHO)] (9), (Cp3tms)2Th[(bipy)(Ph2CO)] (10), (Cp3tms)2Th[(bipy){(p-tolylNH)(Ph)CO}] (11), (Cp3tms)2Th[(bipy){(p-MeOPh)2CSe}] (12), (Cp3tms)2Th[(bipy){(p-tolyl)2CNH}] (13), (Cp3tms)2Th[(bipy)(PhCHNN═CHPh)] (14), (Cp3tms)2Th[(bipy)(PhCN)] (16), (Cp3tms)2Th[(bipy)(PhCH2CN)] (17), and (Cp3tms)2Th[(bipy)(Ph2CHCN)] (18), respectively. However, when thiazole is added to 3, the dimeric sulfido complex [(Cp3tms)2Th]2[μ-(bipy)CH2NCHCHS]2 (15) can be isolated. Moreover, the addition of isonitriles such as Me3CNC and PhCH2NC to 3 results in C-N bond cleavage and C-C coupling processes to form the thorium isocyanido amido complexes (Cp3tms)2Th[4-(Me3C)bipy](NC) (19) and (Cp3tms)2Th[4-(PhCH2)bipy](NC) (20), respectively. Nevertheless, upon exposure of 3 to (trimethylsilyl)diazomethane Me3SiCHN2, the bis-amido complex (Cp3tms)2Th[5,6-(Me3SiCH)bipy] (21), concomitant with N2 release, is isolated.
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Affiliation(s)
- Shichun Wang
- 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
| | - Tongyu Li
- 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, Hagenring 30, Braunschweig 38106, Germany
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4
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Nguyen JQ, Wedal JC, Ziller JW, Furche F, Evans WJ. Investigating Steric and Electronic Effects in the Synthesis of Square Planar 6d 1 Th(III) Complexes. Inorg Chem 2024; 63:6217-6230. [PMID: 38502000 DOI: 10.1021/acs.inorgchem.3c04462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
The factors affecting the formation and crystal structures of unusual 6d1 Th(III) square planar aryloxide complexes, as exemplified by [Th(OArMe)4]1- (OArMe = OC6H2tBu2-2,6-Me-4), were explored by synthetic and reduction studies of a series of related Th(IV) tetrakis(aryloxide) complexes, Th(OArR)4 (OArR = OC6H2tBu2-2,6-R-4). Specifically, electronic, steric, and countercation effects were explored by varying the aryloxide ligand, the alkali metal reducing agent, and the alkali metal chelating agent. Salt metathesis reactions between ThBr4(DME)2 (DME = 1,2-dimethoxyethane) and 4 equiv of the appropriate potassium aryloxide salt were used to prepare a series of Th(IV) aryloxide complexes in high yields: Th(OArH)4 (OArH = OC6H3tBu2-2,6), Th(OArtBu)4 (OArtBu = OC6H2tBu3-2,4,6), Th(OArOMe)4 (OArOMe = OC6H2tBu2-2,6-OMe-4), and Th(OArPh)4 (OArPh = OC6H2tBu2-2,6-Ph-4). Th(OArH)4 can be reduced by KC8, Na, or Li in the absence or presence of 2.2.2-cryptand (crypt) or 18-crown-6 (crown) to form dark purple solutions that have EPR and UV-visible spectra similar to those of the square planar Th(III) complex, [Th(OArMe)4]1-. Hence, the para position of the aryloxide ligand does not have to be alkylated to obtain the Th(III) complexes. Furthermore, reduction of Th(OArOMe)4, Th(OArtBu)4, and Th(OArPh)4 with KC8 in THF generated purple solutions with EPR and UV-visible spectra that are similar to those of the previously reported Th(III) anion, [Th(OArMe)4]1-. Although many of these reduction reactions did not produce single crystals suitable for study by X-ray diffraction, reduction of Th(OArH)4, Th(OArtBu)4, and Th(OArOMe)4 with Li provided X-ray quality crystals whose structures had square planar coordination geometries. Reduction of Th(OArPh)4 with Li also gave a product with EPR and UV-visible spectra that matched those of [Th(OArMe)4]1-, but X-ray quality crystals of the reduction product were too unstable to provide data. Neither Th(Odipp)4(THF)2 (Odipp = OC6H3iPr2-2,6) nor Th(Odmp)4(THF)2 (Odmp = OC6H3Me2-2,6) could be reduced to Th(III) products under similar conditions. Reduction of U(OArH)3(THF) with KC8 in the presence of 2.2.2-cryptand (crypt) was examined for comparison and formed [K(crypt)][U(OArH)4], which has a tetrahedral arrangement of the aryloxide ligands. Moreover, no further reduction was observed when either [K(crypt)][U(OArH)4] or [K(crown)(THF)2][U(OArH)4] were treated with KC8 or Li.
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Affiliation(s)
- Joseph Q Nguyen
- Department of Chemistry, University of California, Irvine, Irvine, California 92697-2025, United States
| | - Justin C Wedal
- Department of Chemistry, University of California, Irvine, Irvine, California 92697-2025, United States
| | - Joseph W Ziller
- Department of Chemistry, University of California, Irvine, Irvine, California 92697-2025, United States
| | - Filipp Furche
- Department of Chemistry, University of California, Irvine, Irvine, California 92697-2025, United States
| | - William J Evans
- Department of Chemistry, University of California, Irvine, Irvine, California 92697-2025, United States
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5
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Wedal JC, Moore WNG, Lukens WW, Evans WJ. Perplexing EPR Signals from 5f 36d 1 U(II) Complexes. Inorg Chem 2024; 63:2945-2953. [PMID: 38279200 DOI: 10.1021/acs.inorgchem.3c03449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2024]
Abstract
Metal complexes with unpaired electrons in orbitals of different angular momentum quantum numbers (e.g., f and d orbitals) are unusual and opportunities to study the interactions among these electrons are rare. X-band electron paramagnetic resonance (EPR) data were collected at <10 and 77 K on 10 U(II) complexes with 5f36d1 electron configurations and on some analogous Ce(II), Pr(II), and Nd(II) complexes with 4fn5d1 electron configurations. The U(II) compounds unexpectedly display similar two-line axial signals with g|| = 2.04 and g⊥ = 2.00 at 77 K. In contrast, U(II) complexes with 5f4 configurations are EPR-silent. Unlike U(II), the congenic 4f35d1 Nd(II) complex is EPR-silent. The Ce(II) complex with a 4f15d1 configuration is also EPR-silent, but a signal is observed for the Pr(II) complex, which has a 4f25d1 configuration. Whether or not an EPR signal is expected for these complexes depends on the coupling between f and d electrons. Since the coupling in U(II) systems is expected to be sufficiently strong to preclude an EPR signal from compounds with a 5f36d1 configuration, the results are viewed as unexplained phenomena. However, they do show that 5f36d1 U(II) samples can be differentiated from 5f4 U(II) complexes by EPR spectroscopy.
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Affiliation(s)
- Justin C Wedal
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - William N G Moore
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - Wayne W Lukens
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - William J Evans
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
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6
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Wedal JC, Murillo J, Ziller JW, Scott BL, Gaunt AJ, Evans WJ. Synthesis of Trimethyltriazacyclohexane (Me 3tach) Sandwich Complexes of Uranium, Neptunium, and Plutonium Triiodides: (Me 3tach) 2AnI 3. Inorg Chem 2022; 62:5897-5905. [PMID: 36576312 DOI: 10.1021/acs.inorgchem.2c03306] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
1,3,5-Trimethyl-1,3,5-triazacyclohexane (Me3tach) readily complexes uranium triiodide to form (Me3tach)2UI3. The complex is soluble in THF and arenes and can function as a source of UI3 to form organometallic U(III) complexes. When dissolved in pyridine (py), (Me3tach)2UI3 forms (Me3tach)UI3(py)2. A related complex with the larger 1,4,7-trimethyl-1,4,7-triazacyclononane (Me3tacn) ligand, namely (Me3tacn)UI3(THF), was synthesized for comparison. Since X-ray quality crystals of (Me3tach)2UI3 can be synthesized in high yield even with small-scale reactions, the system is ideal for extension to transuranium elements. Accordingly, the neptunium and plutonium complexes (Me3tach)2NpI3 and (Me3tach)2PuI3 were synthesized in an analogous manner from NpI3(THF)4 and PuI3(THF)4, respectively.
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Affiliation(s)
- Justin C Wedal
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - Jesse Murillo
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Joseph W Ziller
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - Brian L Scott
- Materials Physics & Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Andrew J Gaunt
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - William J Evans
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
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7
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Wedal JC, Ziller JW, Evans WJ. Expanding Bismuth Trihalide Coordination Chemistry with Trimethyltriazacyclohexane and Trimethyltriazacyclononane. Inorg Chem 2022; 61:11766-11774. [PMID: 35861795 DOI: 10.1021/acs.inorgchem.2c01483] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
1,3,5-Trimethyltriazacyclohexane, Me3tach, readily adds to bismuth triiodide to form a variety of new coordination compounds depending on the stoichiometry, solvent, and crystallization conditions. X-ray crystallographic evidence has been obtained for both 2:1 and 1:1 Me3tach:Bi complexes with formulas of [(Me3tach)2BiI2][(Me3tach)BiI4], [(Me3tach)2BiI2]3[Bi2I9][I][HMe3tach]·THF, and (Me3tach)BiI3(py)2. The related chloride structure (Me3tach)BiCl3(py)2 forms from BiCl3. The structure of (Me3tacn)BiI3 with the larger chelate, 1,4,7-trimethyltriazacyclononane, Me3tacn, was obtained for comparison, and the polymeric structure of BiI3 in THF was defined as [BiI(THF)(μ-I)2]n.
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Affiliation(s)
- Justin C Wedal
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - Joseph W Ziller
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - William J Evans
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
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8
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Boreen MA, Ye CZ, Kerridge A, McCabe KN, Skeel BA, Maron L, Arnold J. Does Reduction-Induced Isomerization of a Uranium(III) Aryl Complex Proceed via C-H Oxidative Addition and Reductive Elimination across the Uranium(II/IV) Redox Couple? Inorg Chem 2022; 61:8955-8965. [PMID: 35654478 DOI: 10.1021/acs.inorgchem.2c01563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Reaction of the uranium(III) bis(amidinate) aryl complex {TerphC(NiPr)2}2U(Terph) (2, where Terph = 4,4″-di-tert-butyl-m-terphenyl-2'-yl) with a strong reductant enabled isolation of isomeric uranium(III) bis(amidinate) aryl product {TerphC(NiPr)2}2U(Terph*) (3, where Terph* = 4,4″-di-tert-butyl-m-terphenyl-4'-yl). In terms of connectivity, 3 differs from 2 only in the positions of the U-C and C-H bonds on the central aryl ring of the m-terphenyl-based ligand. A deuterium labeling study ruled out mechanisms for this isomerization involving intermolecular abstraction or deprotonation of the ligand C-H bonds activated during the reaction. Due to the complexity of this rapid, heterogeneous reaction, experimental studies could not further distinguish between two different intramolecular C-H activation mechanisms. However, high-level computational studies were consistent with a mechanism that included two sets of unimolecular, mononuclear C-H oxidative addition and reductive elimination steps involving uranium(II/IV).
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Affiliation(s)
- Michael A Boreen
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Christopher Z Ye
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Andrew Kerridge
- Department of Chemistry, Lancaster University, Lancaster LA1 4YB, U.K
| | - Karl N McCabe
- LPCNO, Université de Toulouse, INSA Toulouse, 135 Avenue de Rangueil, Toulouse 31077, France
| | - Brighton A Skeel
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Laurent Maron
- LPCNO, Université de Toulouse, INSA Toulouse, 135 Avenue de Rangueil, Toulouse 31077, France
| | - John Arnold
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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9
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Wedal JC, Ziller JW, Furche F, Evans WJ. Synthesis and Reduction of Heteroleptic Bis(cyclopentadienyl) Uranium(III) Complexes. Inorg Chem 2022; 61:7365-7376. [PMID: 35504019 DOI: 10.1021/acs.inorgchem.2c00322] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Heteroleptic U(III) complexes supported by bis(cyclopentadienyl) frameworks have been synthesized to examine their suitability as precursors to U(II) complexes. The newly synthesized (C5Me5)2U(OC6H2tBu2-2,6-Me-4), (C5Me5)2U(OC6H2Ad2-2,6-tBu-4) (Ad = 1-adamantyl), (C5Me5)2U(C5H5), and (C5Me5)2U(C5Me4H) are compared with (C5Me5)2U[N(SiMe3)2], (C5Me5)2U[CH(SiMe3)2], and (C5Me5)U[N(SiMe3)2]2. An improved synthesis of (C5Me5)2U(μ-Ph)2BPh2 was developed, which was used to synthesize (C5Me5)2U(C5Me4H). Since the X-ray crystal structure of (C5Me5)2U(OC6H2tBu2-2,6-Me-4) contained two very different molecules in the asymmetric unit with 115.7(5)° and 166.0(5)° U-O-Cipso angles, the (C5Me4H)2U(OC6H2tBu2-2,6-Me-4) and (C5Me5)2Ce(OC6H2tBu2-2,6-Me-4) analogues were synthesized and characterized by X-ray diffraction for comparison. Electrochemical studies in THF with a 100 mM [nBu4N][BPh4] supporting electrolyte showed U(IV)/U(III) and U(III)/U(II) redox couples for all the heteroleptic complexes except (C5Me5)2U(C5H5). Chemical reduction of all heteroleptic compounds formed dark blue solutions characteristic of U(II) when reacted with KC8 at -78 °C, but none formed isolable U(II) complexes. The targeted U(II) complexes, [(C5Me5)2U(OC6H2tBu2-2,6-Me-4)]1-, {(C5Me5)2U[CH(SiMe3)2]}1-, [(C5Me5)2U(C5H5)]1-, and [(C5Me5)2U(C5Me4H)]1-, were analyzed by density functional theory, and a 5f36d1 electron configuration was found to be the ground state in each case.
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Affiliation(s)
- Justin C Wedal
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - Joseph W Ziller
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - Filipp Furche
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - William J Evans
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
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10
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Wedal JC, Cajiao N, Neidig ML, Evans WJ. Anion-induced disproportionation of Th(III) complexes to form Th(II) and Th(IV) products. Chem Commun (Camb) 2022; 58:5289-5291. [PMID: 35403646 DOI: 10.1039/d2cc01272c] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new synthesis of Th(II) complexes has been identified involving addition of simple MX salts (M = Li, Na, K; X = H, Cl, Me, N3) to Cp''3ThIII [Cp'' = [C5H3(SiMe3)2] in the presence of 18-crown-6 or 2.2.2-cryptand, forming [M(chelate)][Cp''3ThII] and Cp''3ThIVX. Cptet3ThIII (Cptet = C5Me4H) reacts with KH to form Cptet3ThIVH and the C-H bond activation product, [K(crypt)]{[Cptet2ThIVH[η1:η5-C5Me3H(CH2)]}.
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Affiliation(s)
- Justin C Wedal
- Department of Chemistry, University of California, Irvine, California 92697-2025, USA.
| | - Nathalia Cajiao
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA.
| | - Michael L Neidig
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA.
| | - William J Evans
- Department of Chemistry, University of California, Irvine, California 92697-2025, USA.
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11
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Wedal JC, Ziller JW, Evans WJ. Exploring the use of the pentaphenylcyclopentadienyl ligand in uranium chemistry: the crystal structure of (C5Ph5)UI2(THF)2
†. Aust J Chem 2022. [DOI: 10.1071/ch21318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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12
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Goodwin CAP, Ciccone SR, Bekoe S, Majumdar S, Scott BL, Ziller JW, Gaunt AJ, Furche F, Evans WJ. 2.2.2-Cryptand complexes of neptunium(III) and plutonium(III). Chem Commun (Camb) 2021; 58:997-1000. [PMID: 34937074 DOI: 10.1039/d1cc05904a] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
New coordination environments are reported for Np(III) and Pu(III) based on pilot studies of U(III) in 2.2.2-cryptand (crypt). The U(III)-in-crypt complex, [U(crypt)I2][I], obtained from the reaction between UI3 and crypt, is treated with Me3SiOTf (OTf = O3SCF3) in benzene to form the [U(crypt)(OTf)2][OTf] complex. Similarly, the isomorphous Np(III) and Pu(III) complexes were obtained similarly starting from [AnI3(THF)4]. All three complexes (1-An; An = U, Np, Pu) contain an encapsulated actinide in a THF-soluble complex. Absorption spectroscopy and DFT calculations are consistent with 5f3 U(III), 5f4 Np(III), and 5f5 Pu(III) electron configurations.
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Affiliation(s)
- Conrad A P Goodwin
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
| | - Sierra R Ciccone
- Department of Chemistry, University of California Irvine, Irvine, CA 92697-2025, USA.
| | - Samuel Bekoe
- Department of Chemistry, University of California Irvine, Irvine, CA 92697-2025, USA.
| | - Sourav Majumdar
- Department of Chemistry, University of California Irvine, Irvine, CA 92697-2025, USA.
| | - Brian L Scott
- Materials Physics & Applications Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Joseph W Ziller
- Department of Chemistry, University of California Irvine, Irvine, CA 92697-2025, USA.
| | - Andrew J Gaunt
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
| | - Filipp Furche
- Department of Chemistry, University of California Irvine, Irvine, CA 92697-2025, USA.
| | - William J Evans
- Department of Chemistry, University of California Irvine, Irvine, CA 92697-2025, USA.
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13
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Jenkins TF, Bekoe S, Ziller JW, Furche F, Evans WJ. Synthesis of a Heteroleptic Pentamethylcyclopentadienyl Yttrium(II) Complex, [K(2.2.2-Cryptand)]{(C5Me5)2YII[N(SiMe3)2]}, and Its C–H Bond Activated Y(III) Derivative. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00482] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tener F. Jenkins
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Samuel Bekoe
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Joseph W. Ziller
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Filipp Furche
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - William J. Evans
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
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14
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Wedal JC, Furche F, Evans WJ. Density Functional Theory Analysis of the Importance of Coordination Geometry for 5f 36d 1 versus 5f 4 Electron Configurations in U(II) Complexes. Inorg Chem 2021; 60:16316-16325. [PMID: 34644069 DOI: 10.1021/acs.inorgchem.1c02161] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Density functional theory (DFT) calculations on four known and seven hypothetical U(II) complexes indicate the importance of coordination geometry in favoring 5f36d1 versus 5f4 electronic ground states. The known [Cp″3U]-, [Cptet3U]-, and [U(NR2)3]- [Cp″ = C5H3(SiMe3)2, Cptet = C5Me4H, and R = SiMe3] anions were found to have 5f36d1 ground states, while a 5f4 ground state was found for the known compound (NHAriPr6)2U. The UV-visible spectra of the known 5f36d1 compounds were simulated via time-dependent DFT and are in qualitative agreement with the experimental spectra. For the hypothetical U(II) compounds, the 5f36d1 configuration is predicted for [U(CHR2)3]-, [U(H3BH)3]-, [U(OAr')4]2-, and [(C8H8)U]2- (OAr' = O-C6H2tBu2-2,6-Me-4). In the case of [U(bnz')4]2- (bnz' = CH2-C6H4tBu-4), a 5f3 configuration with a ligand-based radical was found as the ground state.
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Affiliation(s)
- Justin C Wedal
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Filipp Furche
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - William J Evans
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
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15
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Boreen MA, Arnold J. The synthesis and versatile reducing power of low-valent uranium complexes. Dalton Trans 2020; 49:15124-15138. [DOI: 10.1039/d0dt03151h] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
This synthesis and diverse reactivity of uranium(iii) and uranium(ii) complexes is discussed.
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Affiliation(s)
- Michael A. Boreen
- Department of Chemistry
- University of California
- Berkeley
- USA
- Chemical Sciences Division
| | - John Arnold
- Department of Chemistry
- University of California
- Berkeley
- USA
- Chemical Sciences Division
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