1
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Shohel M, Sockwell AK, Hixon AE, Nyman M. Plutonium and Cerium Perrhenate/Pertechnetate Coordination Polymers and Frameworks. Inorg Chem 2024; 63:2044-2052. [PMID: 38232388 DOI: 10.1021/acs.inorgchem.3c03846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Spent nuclear fuel (SNF) contains transuranic and lanthanide species, which are sometimes recovered and repurposed. One particularly problematic fission product, 99TcO4-, hampers this recovery via coextraction with high valence metals, perhaps by complexation during aqueous reprocessing of SNF. There is limited molecular-level knowledge concerning the coordination chemistry between TcO4- or its well-known surrogate ReO4- and transuranic/lanthanide species. In the current study, we investigated the coordination of ReO4-/TcO4- with plutonium and cerium cations by structural and chemical characterization of a series of isolated extended solids. In this study, Ce represents both trivalent lanthanides and is considered a surrogate for Pu, respectively, in its common trivalent and tetravalent oxidation states. The structural elucidation of the seven isolated crystalline solids revealed that ReO4-/TcO4- directly connects to PuIV, PuVIO22+, CeIII, and CeIV in the terminal and bridging coordination modes, leading to 1-, 2-, and 3-dimensional frameworks. For example, ReO4- coordination to Pu(IV) formed a 1D chain or 2D framework, isostructural with previously isolated Th(IV) compounds. However, PuVIO22+ alternating with ReO4- led to a unique 1D chain, different from the prior-reported U(VI)/Np(VI)-ReO4-/TcO4- structures. Coordination of ReO4-/TcO4- with Ce(III) promotes the assembly of 3D frameworks. Finally, attempted synthesis of a Ce(IV)-ReO4- compound resulted in a 2D framework with a mixed-valence CeIII/IV. The highly acidic reaction conditions supported the reduction of both CeIV and TcVII, challenging isolation of compounds featuring these species. Only one TcO4-containing structure was obtained in this study (CeIII-TcO4 3D framework), vs the six total Ce/Pu-ReO4 compounds. Our three Pu-ReO4 crystal structures are the first reported and translated to atomic-level information about Pu-TcO4 coordination in nuclear fuel reprocessing scenarios, in addition to broadening our knowledge of bonding trends in the early, high-valence actinides.
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Affiliation(s)
- Mohammad Shohel
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, United States
| | - A Kirstin Sockwell
- Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Amy E Hixon
- Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - May Nyman
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, United States
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2
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Ferrari JJ, Ball TJ, Polinski MJ. Effect of Reaction Time on Lanthanide Borate Perrhenate Complexes. Inorg Chem 2023; 62:4696-4704. [PMID: 36893389 DOI: 10.1021/acs.inorgchem.3c00218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Abstract
Six new trivalent lanthanide borate perrhenate structures─the isostructural series Ln[B8O11(OH)4(H2O)(ReO4)] (Ln = Ce-Nd, Sm, Eu; 1) and La[B6O9(OH)2(H2O)(ReO4)] (2)─have been prepared and structurally characterized. Single-crystal X-ray diffraction analysis reveals that both structures crystallize in the P21/n space group, contain 10-coordinated trivalent lanthanides in a capped triangular cupola geometry, are 3D borate framework materials, and contain either terminal (1) or bridging (2) perrhenate moieties. The presence or lack of a bridging perrhenate, along with the identity of the basal ligands, dictates how the layers are tethered together, ultimately leading to the different structures. Furthermore, the formation of 1 is sensitive to the reaction time employed. Herein, the synthesis, structural descriptions, and spectroscopy of these trivalent lanthanide perrhenate borate complexes are presented.
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Affiliation(s)
- John J Ferrari
- Department of Biochemistry, Chemistry, Engineering, and Physics, Commonwealth University of Pennsylvania, 400 E. 2nd Street, Bloomsburg, Pennsylvania 17815, United States
| | - Tucker J Ball
- Department of Biochemistry, Chemistry, Engineering, and Physics, Commonwealth University of Pennsylvania, 400 E. 2nd Street, Bloomsburg, Pennsylvania 17815, United States
| | - Matthew J Polinski
- Department of Biochemistry, Chemistry, Engineering, and Physics, Commonwealth University of Pennsylvania, 400 E. 2nd Street, Bloomsburg, Pennsylvania 17815, United States
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3
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Löffler ST, Hümmer J, Scheurer A, Heinemann FW, Meyer K. Unprecedented pairs of uranium (iv/v) hydroxido and (iv/v/vi) oxido complexes supported by a seven-coordinate cyclen-anchored tris-aryloxide ligand. Chem Sci 2022; 13:11341-11351. [PMID: 36320575 PMCID: PMC9533418 DOI: 10.1039/d2sc02736d] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 07/30/2022] [Indexed: 08/05/2023] Open
Abstract
We present the synthesis and reactivity of a newly developed, cyclen-based tris-aryloxide ligand precursor, namely cyclen(Me)( t-Bu,t-BuArOH)3, and its coordination chemistry to uranium. The corresponding uranium(iii) complex [UIII((OAr t-Bu,t-Bu)3(Me)cyclen)] (1) was characterized by 1H NMR analysis, CHN elemental analysis and UV/vis/NIR electronic absorption spectroscopy. Since no single-crystals suitable for X-ray diffraction analysis could be obtained from this precursor, 1 was oxidized with methylene chloride or silver fluoride to yield [(cyclen(Me)( t-Bu,t-BuArO)3)UIV(X)] (X = Cl (2), F (3)), which were unambiguously characterized and successfully crystallized to gain insight into the molecular structure by single-crystal X-ray diffraction analysis (SC-XRD). Further, the activation of H2O and N2O by 1 is presented, resulting in the U(iv) complex [(cyclen(Me)( t-Bu,t-BuArO)3)UIV(OH)] (4) and the U(v) complex [(cyclen(Me)( t-Bu,t-BuArO)3)UV(O)] (6). Complexes 2, 3, 4, and 6 were characterized by 1H NMR analysis, CHN elemental analysis, UV/vis/NIR electronic absorption spectroscopy, IR vibrational spectroscopy, and SQUID magnetization measurements as well as cyclic voltammetry. Furthermore, chemical oxidation of 3, 4, and 6 with AgF or AgSbF6 was achieved leading to complexes [(cyclen(Me)( t-Bu,t-BuArO)3)UV(F)2] (5), [(cyclen(Me)( t-Bu,t-BuArO)3)UV(OH)][SbF6] (7), and [(cyclen(Me)( t-Bu,t-BuArO)3)UVI(O)][SbF6] (8). Finally, reduction of 7 with KC8 yielded a U(iv) complex, spectroscopically and magnetochemically identified as K[(cyclen(Me)( t-Bu,t-BuArO)3)UIV(O)].
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Affiliation(s)
- Sascha T Löffler
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Department of Chemistry and Pharmacy Inorganic Chemistry Egerlandstraße 1 91058 Erlangen Germany
| | - Julian Hümmer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Department of Chemistry and Pharmacy Inorganic Chemistry Egerlandstraße 1 91058 Erlangen Germany
| | - Andreas Scheurer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Department of Chemistry and Pharmacy Inorganic Chemistry Egerlandstraße 1 91058 Erlangen Germany
| | - Frank W Heinemann
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Department of Chemistry and Pharmacy Inorganic Chemistry Egerlandstraße 1 91058 Erlangen Germany
| | - Karsten Meyer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Department of Chemistry and Pharmacy Inorganic Chemistry Egerlandstraße 1 91058 Erlangen Germany
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4
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Synthesis and characterization of new families of lanthanide perrhenate complexes. J SOLID STATE CHEM 2022. [DOI: 10.1016/j.jssc.2021.122780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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5
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Huh DN, Barlow JM, Ciccone SR, Ziller JW, Yang JY, Evans WJ. Stabilization of U(III) to Oxidation and Hydrolysis by Encapsulation Using 2.2.2-Cryptand. Inorg Chem 2020; 59:17077-17083. [PMID: 33226794 DOI: 10.1021/acs.inorgchem.0c02286] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The electrochemical properties of U(III)-in-crypt (crypt = 2.2.2-cryptand) were examined in dimethylformamide (DMF) and acetonitrile (MeCN) to determine the oxidative stability offered by crypt as a ligand. Cyclic voltammetry revealed a U(III)/U(IV) irreversible oxidation at EPA= -0.49 V (vs Fe(C5H5)2+/0) in DMF and at EPA= -0.31 V (vs Fe(C5H5)2+/0) in MeCN. The electrochemistry of U(III)-in-crypt complexes in the presence of water was also examined. These studies are supported by crystallographically characterized examples of U(III)-in-crypt complexes as DMF, MeCN, and water adducts.
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Affiliation(s)
- Daniel N Huh
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Jeffrey M Barlow
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Sierra R Ciccone
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Joseph W Ziller
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Jenny Y Yang
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - William J Evans
- Department of Chemistry, University of California, Irvine, California 92697, United States
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6
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Andreev G, Budantseva N, Sokolova M, Fedoseev A. Perrhenate and Pertechnetate Complexes of U(IV), Np(IV), and Pu(IV) with Dimethyl Sulfoxide as an O-Donor Ligand. Inorg Chem 2020; 59:11357-11365. [PMID: 32799473 DOI: 10.1021/acs.inorgchem.0c01036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A series of new dimethyl-sulfoxide-containing pertechnetates and perrhenates of tetravalent U, Np, and Pu were synthesized and structurally characterized by the X-ray diffractometry. In all the synthesized compounds, the actinide atoms were coordinated by eight DMSO molecules with or without an extra XO4- anion in the coordination sphere. This resulted in the square antiprismatic or capped square antiprismatic coordination of An atoms. Three or four XO4- anions play the role of outer-sphere anions. The electron and IR spectra of the compounds correlated with their crystal structure.
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Affiliation(s)
- Grigory Andreev
- Institute of Physical Chemistry and Electrochemistry, 31 Leninsky pr., 119071, Moscow, Russia
| | - Nina Budantseva
- Institute of Physical Chemistry and Electrochemistry, 31 Leninsky pr., 119071, Moscow, Russia
| | - Marina Sokolova
- Institute of Physical Chemistry and Electrochemistry, 31 Leninsky pr., 119071, Moscow, Russia
| | - Aleksander Fedoseev
- Institute of Physical Chemistry and Electrochemistry, 31 Leninsky pr., 119071, Moscow, Russia
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7
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Mashita T, Tsushima S, Takao K. Controlling the lability of uranyl(vi) through intramolecular π-π stacking. Dalton Trans 2018; 47:13072-13080. [PMID: 30167609 DOI: 10.1039/c8dt02600a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
A reaction of UO22+ with cyclohexyldiphenylphosphine oxide (OPCyPh2) in ethanol resulted in a perchlorate salt of the 4-fold homoleptic complex, [UO2(OPCyPh2)4](ClO4)2·EtOH. X-ray structure determination revealed that [UO2(OPCyPh2)4]2+ shows a highly symmetric molecular structure supported by the intramolecular π-π stacking interactions between the phenyl groups of the neighbouring OPCyPh2 in the equatorial plane of UO22+. To clarify whether the reactivity of UO22+ is affected by such a unique coordination structure, the ligand exchange kinetics of [UO2(OPCyPh2)4]2+ in non-coordinating solvents has been studied using an NMR line-broadening method. In CD2Cl2 and CD3NO2 solutions, both signals of coordinated and free OPCyPh2 appeared distinctively even at 298 K, while 2D EXSY experiment provided evidence that a chemical exchange between [UO2(OPCyPh2)4]2+ and free OPCyPh2 occurs in these systems. Thus, this ligand exchange reaction is quite slow on the NMR time-scale. The dependency of the apparent first-order rate constant (kobs) on temperature and the free OPCyPh2 concentration suggested that this ligand exchange reaction involves associative and dissociative mechanisms both governed by large negative ΔS‡ terms predominantly. Compared with the kinetic data of ligand exchange reactions of other UO22+ complexes reported so far, the lability of UO22+ in [UO2(OPCyPh2)4]2+ is found to be significantly suppressed due to the intramolecular π-π stacking interactions as observed in the crystal structure. The DFT calculations successfully reproduced the intramolecular π-π stacking in [UO2(OPCyPh2)4]2+ by considering the empirical dispersion corrections, and provided theoretical rationales to the A and D mechanisms of the ligand exchange reaction of [UO2(OPCyPh2)4]2+.
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Affiliation(s)
- Takanori Mashita
- Laboratory for Advanced Nuclear Energy, Institute of Innovative Research, Tokyo Institute of Technology, 2-12-1 N1-32, O-okayama, Meguro-ku, 152-8550 Tokyo, Japan.
| | - Satoru Tsushima
- Tokyo Tech World Research Hub Initiative (WRHI), Institute of Innovative Research, Tokyo Institute of Technology, 2-12-1, O-okayama, Meguro-ku, 152-8550 Tokyo, Japan. and Institute of Resource Ecology, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstrasse 400, 01328 Dresden, Germany.
| | - Koichiro Takao
- Laboratory for Advanced Nuclear Energy, Institute of Innovative Research, Tokyo Institute of Technology, 2-12-1 N1-32, O-okayama, Meguro-ku, 152-8550 Tokyo, Japan.
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8
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Huh DN, Windorff CJ, Ziller JW, Evans WJ. Synthesis of uranium-in-cryptand complexes. Chem Commun (Camb) 2018; 54:10272-10275. [PMID: 30140826 DOI: 10.1039/c8cc05341c] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The facile encapsulation of U(iii) and La(iii) by 2.2.2-cryptand (crypt) using simple starting materials is described. Addition of crypt to UI3 and LaCl3 forms the crystallographically-characterizable complexes, [U(crypt)I2]I and [La(crypt)Cl2]Cl. In the presence of water, the U(iii)-aquo adducts, [U(crypt)I(OH2)][I]2 and [U(crypt)I(OH2)][I][BPh4], can be isolated.
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Affiliation(s)
- Daniel N Huh
- Department of Chemistry, University of California-Irvine, Irvine, California 92697, USA.
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9
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Uranium-mediated electrocatalytic dihydrogen production from water. Nature 2016; 530:317-21. [PMID: 26808900 DOI: 10.1038/nature16530] [Citation(s) in RCA: 125] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 12/07/2015] [Indexed: 01/18/2023]
Abstract
Depleted uranium is a mildly radioactive waste product that is stockpiled worldwide. The chemical reactivity of uranium complexes is well documented, including the stoichiometric activation of small molecules of biological and industrial interest such as H2O, CO2, CO, or N2 (refs 1 - 11), but catalytic transformations with actinides remain underexplored in comparison to transition-metal catalysis. For reduction of water to H2, complexes of low-valent uranium show the highest potential, but are known to react violently and uncontrollably forming stable bridging oxo or uranyl species. As a result, only a few oxidations of uranium with water have been reported so far; all stoichiometric. Catalytic H2 production, however, requires the reductive recovery of the catalyst via a challenging cleavage of the uranium-bound oxygen-containing ligand. Here we report the electrocatalytic water reduction observed with a trisaryloxide U(III) complex [(((Ad,Me)ArO)3mes)U] (refs 18 and 19)--the first homogeneous uranium catalyst for H2 production from H2O. The catalytic cycle involves rare terminal U(IV)-OH and U(V)=O complexes, which have been isolated, characterized, and proven to be integral parts of the catalytic mechanism. The recognition of uranium compounds as potentially useful catalysts suggests new applications for such light actinides. The development of uranium-based catalysts provides new perspectives on nuclear waste management strategies, by suggesting that mildly radioactive depleted uranium--an abundant waste product of the nuclear power industry--could be a valuable resource.
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10
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Maerzke KA, Goff GS, Runde WH, Schneider WF, Maginn EJ. Structure and Dynamics of Uranyl(VI) and Plutonyl(VI) Cations in Ionic Liquid/Water Mixtures via Molecular Dynamics Simulations. J Phys Chem B 2013; 117:10852-68. [DOI: 10.1021/jp405473b] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
| | - George S. Goff
- Chemistry
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Wolfgang H. Runde
- Chemistry
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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11
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Li C, Peng X, Zhang SC, Chai LY, Yi XY. Heteropolymetallic complexes containing ReO4−: Catalytic oxidation of sulfide. Inorganica Chim Acta 2013. [DOI: 10.1016/j.ica.2012.12.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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12
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Charushnikova IA, Fedosseev AM, Den Auwer C, Moisy P. Crystal structure of Th(IV) perchlorate and U(VI) nitrate complexes with trimethyl phosphate: [Th(OP(OCH
3
)
3
)
4
(O
2
P(OCH
3
)
2
)
2
]
2
[ClO
4
]
4
and [UO
2
(OP(OCH
3
)
3
)(O
2
P(OCH
3)2)(NO3)]
2. RADIOCHIM ACTA 2011. [DOI: 10.1524/ract.2012.1899] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Single crystals of [Th(TMP)4(DMP)2]2[ClO4]4 and [UO2(TMP)(DMP)(NO3)]2 have been synthesized and their structures have been determined by X-ray diffraction analysis. The complexes of Th(IV) and U(VI) contain simultaneously both the molecular ligand trimethyl phosphate (TMP) and the anion dimethyl phosphate. The main structural motif in Th(IV) complex is centrosymmetric dimeric cation [Th(TMP)4(DMP)2]
2
4+
, and in U(VI) it is the neutral centrosymmetric dimeric complex [UO2(TMP)(DMP)(NO3)]2. Coordination polyhedron of Th(IV) is tetragonal antiprism, for U(VI) it is pentagonal bipyramid. The structures are compared with those of other Th(IV) and U(VI) complexes containing other trialkyl phosphates.
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Affiliation(s)
- I. A. Charushnikova
- Russian Academy of Sciences, A. N. Frumkin Institute of Physical Chemistry and, Moscow, Russische Föderation
| | | | | | - Philippe Moisy
- CEA Marcoule, Radiochemistry and Process Department, Bagnols sur Cèze Cedex, Frankreich
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13
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Hardwick HC, Royal DS, Helliwell M, Pope SJA, Ashton L, Goodacre R, Sharrad CA. Structural, spectroscopic and redox properties of uranyl complexes with a maleonitrile containing ligand. Dalton Trans 2011; 40:5939-52. [PMID: 21526261 DOI: 10.1039/c0dt01580f] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction of uranyl nitrate hexahydrate with the maleonitrile containing Schiff base 2,3-bis[(4-diethylamino-2-hydroxybenzylidene)amino]but-2-enedinitrile (salmnt((Et(2)N)(2))H(2)) in methanol produces [UO(2)(salmnt((Et2N)2))(H(2)O)] (1) where the uranyl equatorial coordination plane is completed by the N(2)O(2) tetradentate cavity of the (salmnt((Et(2)N)(2)))(2-) ligand and a water molecule. The coordinated water molecule readily undergoes exchange with pyridine (py), dimethylsulfoxide (DMSO), N,N-dimethylformamide (DMF) and triphenylphosphine oxide (TPPO) to give a series of [UO(2)(salmnt((Et(2)N)(2)))(L)] complexes (L = py, DMSO, DMF, TPPO; 2-5, respectively). X-Ray crystallography of 1-5 show that the (salmnt((Et(2)N)(2)))(2-) ligand is distorted when coordinated to the uranyl moiety, in contrast to the planar structure observed for the free protonated ligand (salmnt((Et(2)N)(2))H(2)). The Raman spectra of 1-5 only display extremely weak bands (819-828 cm(-1)) that can be assigned to the typically symmetric O=U=O stretch. This stretching mode is also observed in the infrared spectra for all complexes 1-5 (818-826 cm(-1)) predominantly caused by the distortion of the tetradentate (salmnt((Et(2)N)(2)))(2-) ligand about the uranyl equatorial plane resulting in a change in dipole for this bond stretch. The solution behaviour of 2-5 was studied using NMR, electronic absorption and emission spectroscopy, and cyclic voltammetry. Complexes 2-5 exhibit intense absorptions in the visible region of the spectrum due to intramolecular charge transfer (ICT) transitions and the luminescence lifetimes (< 5 ns) indicate the emission arises from ligand-centred excited states. Reversible redox processes assigned to the {UO(2)}(2+)/{UO(2)}(+) couple are observed for complexes 2-5 (2: E(1/2) = -1.80 V; 3,5: E(1/2) = -1.78 V; 4: E(1/2) = -1.81 V : vs. ferrocenium/ferrocene {Fc(+)/Fc}, 0.1 M Bu(4)NPF(6)) in dichloromethane (DCM). These are some of the most negative half potentials for the {UO(2)}(2+)/{UO(2)}(+) couple observed to date and indicate the strong electron donating nature of the (salmnt((Et(2)N)(2)))(2-) ligand. Multiple uranyl redox processes are clearly seen for [UO(2)(salmnt((Et(2)N)(2)))(L)] in L (L = py, DMSO, DMF; 2-4: 0.1 M Bu(4)NPF(6)) indicating the relative instability of these complexes when competing ligands are present, but the reversible {UO(2)}(2+)/{UO(2)}(+) couple for the intact complexes can still be assigned and shows the position of this couple can be modulated by the solvation environment. Several redox processes were also observed between +0.2 and +1.2 V (vs. Fc(+)/Fc) that prove the redox active nature of the maleonitrile-containing ligand.
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Affiliation(s)
- Helen C Hardwick
- Centre for Radiochemistry Research, School of Chemistry, The University of Manchester, Oxford Road, Manchester, United Kingdom M13 9PL
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14
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15
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Thuéry P. Lanthanide Complexes with Cucurbit[n]urils (n = 5, 6, 7) and Perrhenate Ligands: New Examples of Encapsulation of Perrhenate Anions. Inorg Chem 2009; 48:4497-513. [DOI: 10.1021/ic900328z] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Pierre Thuéry
- CEA, IRAMIS, SIS2M (CNRS URA 331), LCCEf, Bât. 125, F-91191 Gif-sur-Yvette, France
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16
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Fedosseev A, Grigoriev M, Charushnikova I, Budantseva N, Starikova Z, Moisy P. Synthesis, crystal structure and some properties of new perrhenate and pertechnetate complexes of Nd3+ and Am3+ with 2,6-bis(tetramethylfurano)-1,2,4-triazin-3-yl)-pyridine, tris(2-pyridylmethyl)amine and N,N′-tetraethylmalonamide. Polyhedron 2008. [DOI: 10.1016/j.poly.2007.12.029] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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17
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Bart SC, Meyer K. Highlights in Uranium Coordination Chemistry. STRUCTURE AND BONDING 2008. [DOI: 10.1007/430_2007_081] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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18
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Berthet JC, Siffredi G, Thuéry P, Ephritikhine M. Controlled Chemical Reduction of Uranyl Salts into UX4(MeCN)4 (X = Cl, Br, I) with Me3SiX Reagents. Eur J Inorg Chem 2007. [DOI: 10.1002/ejic.200700272] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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19
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John GH, May I, Sarsfield MJ, Collison D, Helliwell M. Dimeric uranyl complexes with bridging perrhenates. Dalton Trans 2007:1603-10. [PMID: 17426862 DOI: 10.1039/b614481k] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction between [UO2(ReO4)2.H(2)O] and two equivalents of either tri-n-butyl phosphine oxide (TBPO) or tri-iso-butyl phosphate (TiBP) results in the formation of [UO2(mu2-ReO4)(ReO4)(TBPO)2]2 (1) and [UO2(mu2-ReO4)(ReO4)(TiBP)2]2 (2) respectively. Both complexes crystallise as two structurally similar centrosymmetric dimers, the cores containing two uranyl moieties linked by bridging perrhenates. Two P=O donor ligands and one monodenatate perrhenate complete the pentagonal bipyramidal coordination sphere at each metal centre. Both complexes have also been characterised in the solid state by vibrational and absorption spectroscopy. Solution spectroscopic characterisation indicates that both perrhenate and phosphine oxide (1) or phosphate (2) remain coordinated, although it is not possible to state conclusively that the dimeric species remain intact. A low resolution structural study of a minor product from the reaction that yielded revealed a monomeric complex with only monodentate perrhenate coordination, [UO2(ReO4)2(H2O)(TiBP)2] (2'). These results represent the first structural evidence for the bridging coordination mode of perrhenate on coordination to an actinide and yields further insight into the possible solvent phase pertechnetate complexes that may exist in PUREX process phosphate rich solvent.
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Affiliation(s)
- Gordon H John
- Centre for Radiochemistry Research, School of Chemistry, The University of Manchester, Manchester M13 9PL, UK
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Kannan S, Moody MA, Barnes CL, Duval PB. Fluoride Abstraction and Reversible Photochemical Reduction of Cationic Uranyl(VI) Phosphine Oxide Complexes. Inorg Chem 2006; 45:9206-12. [PMID: 17083218 DOI: 10.1021/ic060742e] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The syntheses, structural and spectroscopic characterization, fluoride abstraction reactions, and photochemical reactivity of cationic uranyl(VI) phosphine oxide complexes are described. [UO2(OPPh3)4][X]2 (1a, X = OTf; 1b, X = BF4) and [UO2(dppmo)2(OPPh3)][X]2 (2a, X = OTf; 2b, X = BF(4)) are prepared from the corresponding uranyl(VI) chloride precursor and 2 equiv each of AgX and phosphine oxide. The BF4- compounds 1b and 2b are prone to fluoride abstraction reactions in methanol, leading to dinuclear fluoride-bridged uranyl(VI) complexes. Fluoride abstraction of 2b in methanol generates two structural isomers of the fluoride-bridged uranyl(VI) dimer [(UO2(dppmo)2)2(mu-F)][BF4]3 (4), both of which have been structurally characterized. In the major isomer 4C, the four dppmo ligands are all chelating, while in the minor isomer 4B, two of the dppmo ligands bridge adjacent uranyl(VI) centers. Photolysis of 2b in methanol proceeds through 4 to form the uranium(IV) fluoride complex [UO2F2(dppmo)3][BF4]2 (5), involving another fluoride abstraction step. X-ray crystallography shows 5 to be a rare example of a structurally characterized uranium(IV) complex possessing terminal U-F bonds. Complex 5 reverts to 4 in solution upon exposure to air.
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Affiliation(s)
- Shanmugaperumal Kannan
- Department of Chemistry, University of Missouri-Columbia, 601 South College Avenue, Columbia, Missouri 65211, USA
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Ephritikhine M. The vitality of uranium molecular chemistry at the dawn of the XXIst century. Dalton Trans 2006:2501-16. [PMID: 16718334 DOI: 10.1039/b603463b] [Citation(s) in RCA: 264] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The intent of this Dalton Perspective is to highlight the recent advances in uranium molecular chemistry, with the results reported during the 2000-2006 period. This discipline is currently witnessing an impressive development, together with the theoretical chemistry and solid-state chemistry of the f-elements, and its face has profoundly changed, revealing unsuspected structural and reactivity features. This progress required and was facilitated by the use of new precursors. Studies of low-valent compounds gave a better insight into lanthanide(III)/actinide(III) differentiation and led to the discovery of unusual reactions, including activation of small molecules. A number of tetravalent uranium complexes, in particular polynuclear compounds, have been synthesized, which exhibit exciting structures and physicochemical properties. The potential of uranium(III) and uranium(IV) complexes in catalysis has been confirmed. The uranyl complexes, from mononuclear species to supramolecular assemblies, reveal a variety of novel structures, changing the generally accepted ideas on the coordination geometry and the stability of the UO2(2+) ion.
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Affiliation(s)
- Michel Ephritikhine
- Service de Chimie Moléculaire, DSM, DRECAM, Laboratoire Claude Fréjacques (CNRS URA 331), CEA/Saclay, 91191, Gif-sur-Yvette, France.
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Sutton AD, May I, Sharrad CA, Sarsfield MJ, Helliwell M. The coordination of perrhenate and pertechnetate to thorium(iv) in the presence of phosphine oxide or phosphate ligands. Dalton Trans 2006:5734-42. [PMID: 17146538 DOI: 10.1039/b611046k] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of thorium(IV) perrhenato- and pertechnetato-complexes with P[double bond, length as m-dash]O donor ligands have been prepared and characterised both in the solid state and in solution. Isostructural complexes of general formula [Th(MO(4))(4)(L)(4)], where M = Re or Tc and L = triethylphosphate (TEP) (2 and 7), tri-iso-butylphosphate (TiBP) (3 and 8) and tri-n-butylphosphine oxide (TBPO) (4 and 9) have been prepared from the novel starting materials [Th(ReO(4))(4)] x 4H(2)O (1) and [Th(TcO(4))(4)] x 4H(2)O (6). The reaction of or with triphenylphosphine oxide (TPPO) in MeOH has also led to the synthesis of [Th(MO(4))(3)(TPPO)(3)(OCH(3))(HOCH(3))] (M = Re (5) or Tc (10)). While the structural characterisation of 4 and 9 has been previously described, we report for the first time the structural characterisation of 2 and 5, with a partial structural refinement of 3. Vibrational spectroscopic analysis confirms that the Tc complexes not characterised by single crystal X-ray diffraction are indeed isostructural with the perrhenate complexes with the same P[double bond, length as m-dash]O donor ligand. In all cases, monodentate coordination of the Group 7 tetraoxo anion is observed. (31)P NMR spectroscopy indicates that in all the phosphine oxide-based complexes there is one dominant solution species. For the phosphate based systems, the presence of pertechnetate appears to inhibit P[double bond, length as m-dash]O donor ligand complexation in solution, whereas a significant proportion of each phosphate remains coordinated to Th(IV) when perrhenate is present as the counter ligand. These results give some indication as to the mechanism of pertechnetate co-extraction with tetravalent cations in the presence of tri-n-butyl phosphate in the Plutonium and Uranium Recovery by Extraction (PUREX) process.
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Affiliation(s)
- Andrew D Sutton
- Centre for Radiochemistry Research, School of Chemistry, The University of Manchester, Manchester, UKM13 9PL.
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