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Article

Synthesis and Characterisation of Molecular Polarised-Covalent Thorium-Rhenium and -Ruthenium Bonds

by
Joseph P. A. Ostrowski
,
Ashley J. Wooles
and
Stephen T. Liddle
*
Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, UK
*
Author to whom correspondence should be addressed.
Inorganics 2021, 9(5), 30; https://0-doi-org.brum.beds.ac.uk/10.3390/inorganics9050030
Submission received: 13 April 2021 / Revised: 19 April 2021 / Accepted: 20 April 2021 / Published: 21 April 2021
(This article belongs to the Special Issue Cornerstones in Contemporary Inorganic Chemistry)
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Abstract

:
Separate reactions of [Th{N(CH2CH2NSiMe2But)2(CH2CH2NSi(Me)(But)(μ-CH2)]2 (1) with [Re(η5-C5H5)2(H)] (2) or [Ru(η5-C5H5)(H)(CO)2] (3) produced, by alkane elimination, [Th(TrenDMBS)Re(η5-C5H5)2] (ThRe, TrenDMBS = {N(CH2CH2NSiMe2But)3}3-), and [Th(TrenDMBS)Ru(η5-C5H5)(CO)2] (ThRu), which were isolated in crystalline yields of 71% and 62%, respectively. Complex ThRe is the first example of a molecular Th-Re bond to be structurally characterised, and ThRu is only the second example of a structurally authenticated Th-Ru bond. By comparison to isostructural U-analogues, quantum chemical calculations, which are validated by IR and Raman spectroscopic data, suggest that the Th-Re and Th-Ru bonds reported here are more ionic than the corresponding U-Re and U-Ru bonds.

1. Introduction

The field of metal–metal bonds is mature and vast with many applications [1,2,3,4,5]. Whilst homopolymetallic d transition metal systems dominate this still burgeoning field [1,2,3], heteropolymetallic derivatives have been gaining prominence [3,4,5]. Where actinide elements are concerned, in the absence of isolable homopolymetallic species under normal conditions [6], a growing number of heteropolymetallic derivatives have been isolated and characterised [7,8,9,10,11], including Th and U complexes exhibiting bonds to d transition metals such as Mo [12], Fe [13,14,15,16,17,18,19], Ru [13,14,19,20], Re [21,22,23], Co [24,25,26], Rh [27,28,29], Ni [30,31,32,33,34,35], Pd [31], Pt [31,36], Cu [37,38], and Ag [39], and p main group metals and metalloids such as Al [40,41], Ga [41,42], Si [43,44,45,46], Ge [47], Sn [48,49], Sb [50], and Bi [50,51,52].
For some time now we have had an interest in the study of f-block-metal bonds, but most of our efforts have focussed on the synthesis and characterisation of U-derivatives. Of particular pertinence to this paper are the U-Re and U-Ru complexes [U(TrenDMBS)Re(η5-C5H5)2] (URe) [22] and [U(TrenDMBS)Ru(η5-C5H5)(CO)2] (URu) [20], respectively (TrenDMBS = {N(CH2CH2NSiMe2But)3}3-). During our studies, we noted that there are no examples of structurally authenticated molecular Th-Re complexes to date, and that there is only one example of a structurally characterised Th-Ru complex, namely, [Th(η5-C5Me5)2(I)Ru(η5-C5H5)(CO)2] (I) reported by Marks in 1985 [19]. Since URe and URu had proven to be accessible by salt and alkane elimination strategies [20,22], we sought to prepare and characterise the corresponding Th-derivatives so that comparisons between Th and U could be made.
Here, we report the synthesis and characterisation of two new Th-complexes that exhibit bonds to Re and Ru and compare them to the previously reported U-congeners. We find that these Th-complexes exhibit more ionic Th-Re/-Ru bonds than the U-analogues; by validating quantum chemical calculations with spectroscopic vibrational data, we have identified the strength of these Th-Re/-Ru bonds indirectly using Ru-carbonyls as reporters, and we have probed the Th-Re and Th-Ru bonds directly using Raman spectroscopy.

2. Results and Discussion

2.1. Synthesis and Isolation of the Th-Re and Th-Ru Complexes ThRe and ThRu

Treatment of the colourless thorium-cyclometallate complex [Th{N(CH2CH2NSiMe2But)2(CH2CH2NSi(Me)(But)(μ-CH2)]2 (1) [53] with two equivalents of the pale yellow rhenium complex [Re(η5-C5H5)2(H)] (2) [54] in toluene, Scheme 1, afforded a dark yellow solution. Work-up afforded yellow crystals of the Th-Re complex [Th(TrenDMBS)Re(η5-C5H5)2] (ThRe) in 71% isolated yield. Thus, as was found for analogous uranium chemistry,22 alkane elimination is an effective method for constructing thorium-metal bonds.
Encouraged by the successful synthesis of ThRe by alkane elimination, we also treated 1 with two equivalents of the yellow ruthenium complex [Ru(η5-C5H5)(H)(CO)2] (3) [55] in benzene, Scheme 1. Subsequent removal of the reaction mother liquor from the resulting pale yellow precipitate and recrystallisation afforded the Th-Ru complex [Th(TrenDMBS)Ru(η5-C5H5)(CO)2] (ThRu), isolated as light brown crystals of the benzene solvate in 62% yield.

2.2. Solid-State Structures of the Th-Re and Th-Ru Complexes ThRe and ThRu

The solid-state structures of ThRe and ThRu were determined by X-ray Diffraction, Figure 1. The structure of ThRe, Figure 1a, confirms the anticipated trigonal bipyramidal thorium ion and Th-Re bond, which is the first example of a molecular Th-Re bond. The Th-Re distance is found to be 3.1117(2) Å. By definition there are no other Th-Re bonds for comparison, but this distance is marginally (~0.05 Å) longer than the sum of the single covalent bond radii and Th and Re (3.06 Å) [56], and is ~0.06 Å longer than the U-Re distance of 3.0479(6) Å in URe [22], which is in-line with the different single bond covalent radii of Th (1.75 Å) and U (1.70 Å). The Namine-Th-Re angle is 156.37(9)°, and whilst this is approximately trans in nature, the deviation perhaps reflects that the DMBS substituents allow the TrenDMBS unit to flex from C3 symmetry towards a Cs symmetry to accommodate the rhenocene fragment. All other distances and angles are unremarkable.
The structure of ThRu, Figure 1b, confirms the presence of a Th-Ru bond and thus the absence of any isocarbonyl linkages. The Th-Ru distance is found to be 3.1227(3) Å, which compares to a value of 3.00 Å for the sum of the single bond covalent radii of Th and Ru [56]. There is only one other example of a molecular Th-Ru bond, which is I reported in 1985, that exhibits a Th-Ru distance of 3.0277(6) Å [19]. Thus, the Th-Ru distance in ThRu can be considered to be long, likely reflecting charge polarisation into the Ru-CO back-bonding orbitals rendering the Ru a poorer donor site than the Re in rhenocene; support for this comes from the spectroscopic data (see below) and the fact that the U-Ru distance of 3.0739(2) Å in URu is ~0.05 Å shorter, in-line with the respective metal single bond covalent radii [56]. The Ru-CCO and C-O distances in ThRu average 1.844(4) and 1.165(4) Å, respectively. The latter is slightly longer than the C-O distance in free CO (1.128 Å), and the Ru-CCO and C-O distances are similar to the analogous distances in URu [20]. The Namine-Th-Ru angle is 156.60(6)°, which is rather similar to the Namine-Th-Re angle in ThRe.

2.3. Spectroscopic and Analytical Characterisation of the Th-Re and Th-Ru Complexes ThRe and ThRu

The 1H and 13C{1H} NMR spectra of ThRe and ThRu exhibit resonances in the ranges 0–4 and 0–5 ppm, consistent with the diamagnetic, closed-shell formulations of Th(IV) and the Re and Ru ions. The NMR spectra of ThRe and ThRu are largely as anticipated, though the CO C-resonances for ThRu and Cp C-resonances could not be located despite extensive attempts to locate them. The NMR and IR data for ThRe and ThRu do not provide any evidence for hydrides, and their isostructural natures compared to the corresponding U-complexes support the view that there are not any hydrides in ThRe and ThRu.
The IR spectrum of ThRu exhibits strong carbonyl absorptions at 1943 and 1869 cm−1, which can be compared to those of URu (1944, 1872 cm−1) [20], I (1968, 1900 cm−1),19 and [Th(η5-C5H5)3Ru(η5-C5H5)(CO)2] (1915, 1847 cm−1) [13]. It can thus be noted that there is more Ru-CO back-bonding in ThRu compared to I [19] but less than [Th(η5-C5H5)3Ru(η5-C5H5)(CO)2] [13], which would be expected to render the Ru-centre in ThRu a weaker donor; in that scenario, a longer Th-Ru bond would be predicted in ThRu compared to I, which is the only other Th-Ru complex to be structurally characterised, and that is indeed the experimental observation. These data suggest that the [Th(TrenDMBS)]+ fragment is slightly more electron-deficient than [Th(η5-C5H5)3]+, since an An-fragment that polarises charge from the Ru-component most will deplete the extent of Ru-CO back-bonding the most resulting in a higher CO stretching frequency. Conversely, the exchange for a Cp ligand for iodide, even with two cyclopentadienyl ligands replaced by the more strongly donating pentamethylcyclopentadienyl ligand, renders [Th(η5-C5Me5)2(I)]+ the most electron deficient fragment. The magnitude of the shift of the asymmetric CO stretching frequency to high frequency compared to [Ru(η5-C5H5)(CO)2]− (1749 cm−1) reveals a shift of 120 cm−1 [20], which is lower than the shift observed for group 4-group 8 bonds (140–150 cm−1) [4] but higher than for analogous lanthanide-group 8 bonds (110 cm−1) [4,8,10], suggesting that the Th-Ru linkage in ThRu is more covalent than lanthanide analogues but still largely dominated by ionic character.
We also recorded Raman spectra of ThRe and ThRu, and of most pertinence are inelastic scattering bands at 103/136 and 112 cm−1, respectively. On the basis of analytical frequencies calculations on ThRu and ThRu (see below), these are assigned as corresponding to Th-Re and Th-Ru stretches, respectively. For comparison, the W-W stretch for [W2(CO)10][K(18-crown−6)(THF)2] was recently reported to be found at 97 cm−1 by Raman spectroscopy [57].

2.4. Quantum Chemical Computational Analysis of the Th-Re and Th-Ru Complexes ThRe and ThRu

In order to probe the Th-Re/-Ru linkages in ThRe and ThRu, we performed scalar relativistic DFT calculations on the full structures of these two complexes. The optimised gas-phase geometries (see Supplementary Materials for final coordinates and energies) compare well to the experimental solid-state structures, for example, returning Th-Re and Th-Ru distances of 3.1293 and 3.1139 Å, which are in excellent agreement with the experimental values of 3.1117(2) and 3.1227(3) Å. We therefore conclude that the computed models of ThRe and ThRu provide qualitative and representative models of the electronic structures of these complexes.
The computed MDC-q charges for the two Th, Re, and Ru ions in ThRe and ThRu are 1.87, 1.41, 0.38, and 0.71, respectively. These values can be compared to the two U, Re, and Ru values of 1.88, 1.50, 0.38, and 0.67 [20,22], respectively, for the analogous U-complexes, showing negligible variations. The calculated Nalewajski–Mrozek Th-Re and Th-Ru bond orders for ThRe and ThRu are 0.72 and 0.52. Interestingly, in contrast to the largely invariant computed charges, the calculated bond orders for ThRe and ThRu are lower than for URe and URu, which have computed bond orders of 1.13 and 0.76, respectively [20,22], suggesting more ionic metal–metal bonds for the thorium complexes compared to the uranium ones. For comparison, the Th-Namide and Th-Namine bond orders are calculated to average 0.95 and 0.28. The Ru-CCO and C-O bond orders for ThRu average 1.24 and 2.32, respectively, reflecting the back-bonding of electron density from Ru to C with concomitant reduction of the CO bond order from 3 in free CO.
The HOMO-1 and HOMO-2 for complex ThRe represent the principal possible Th-Re bonding interactions on symmetry grounds, Figure 2a,b. HOMO-2 constitutes the Th-Re σ-bond, being derived from the 2a1 orbital from bent metallocene molecular orbital considerations. HOMO-2 contains only 5.9% Th-character, compared to 10.8% U-character in the isostructural U-derivative [22]. HOMO-1 is the corresponding b2 orbital, but unlike the U-analogue which shows a π-bond, in ThRe this MO remains largely localised on the rhenocene fragment (<2% Th character, cf 9.9% U character in the U-analogue). Together, these observations nicely account for the reduced Th-Re bond order compared to the larger U-Re bond order in the isostructural U-congener [22]. The HOMO of ThRe is the 1a1 orbital, and it is essentially non-bonding with respect to the Th-Re bonding interaction; the energy ordering of the 1a1, b2, and 2a1 orbitals in ThRe can thus be related to the degree of stabilisation afforded to those orbitals by how strongly they donate to the Th ion in ThRe.
The HOMO of ThRu represents the Th-Ru interaction, Figure 2c. As found analogously for URu [20], this MO is [Ru(η5-C5H5)(CO)2]-centred (60%), with ~29% 4d character, and 9.6 and 5.8% 5p and 5s character, respectively, with the remaining 15.6% involving the CO π * orbital coefficients. The rest of this MO is delocalised over the TrenDMBS ligand or Th (0.7%), revealing a largely ionic Th-Ru interaction and one where the CO stretching frequency is confirmed as a reporter of the Th-Ru bonding interaction, as discussed above.
Lastly, an analytical frequencies calculation predicts CO stretching frequencies of 1924 and 1864 cm−1 for ThRu, which are in excellent agreement with the experimentally observed values of 1943 and 1869 cm−1. This experimental confirmation of the accuracy of the DFT calculations then permits us to address the Th-Re and Th-Ru bond vibrations in ThRe and ThRu. The Th-Ru stretch for ThRu is computed to occur at 126 cm−1, which is in good agreement with the corresponding experimental Raman value of 112 cm−1. The Th-Re stretch of ThRe appears to be split by coupling to other vibrational modes, principally characterised by bands computed at 107 and 138 cm−1, which compares to experimentally observed bands at 103 and 136 cm−1.

3. Materials and Methods

3.1. General Materials and Methods

All manipulations were carried out using Schlenk techniques, or an MBraun UniLab glovebox, under an atmosphere of dry nitrogen. Solvents were dried by passage through activated alumina towers and degassed before use. Deuterated solvents were dried over NaK2, distilled, and stored over NaK2. Crystals were examined using either a Rigaku FR-X diffractometer, equipped with a HyPix 6000HE photon counting pixel array detector with mirror-monochromated Cu Kα (λ = 1.5418 Å) radiation or a Rigaku Xcalibur2 diffractometer, equipped with an Atlas CCD area detector and a sealed tube source with graphite-monochromated Mo Kα radiation (λ = 0.71073 Å). Intensities were integrated from a sphere of data recorded on narrow (1.0°) frames by ω rotation. Cell parameters were refined from the observed positions of all strong reflections in each data set. Gaussian grid face-indexed absorption corrections with a beam profile correction were applied. The structures were solved by dual methods, and all non-hydrogen atoms were refined by full-matrix least-squares on all unique F2 values with anisotropic displacement parameters with exceptions noted in the respective cif files. Except where noted, hydrogen atoms were refined with constrained geometries and riding thermal parameters. CrysAlisPro [58] was used for control and integration, SHELXT [59] was used for structure solution, and SHELXL [60] and Olex2 [61] were employed for structure refinement. ORTEP-3 [62] and POV-Ray [63] were employed for molecular graphics. FTIR spectra were recorded on a Bruker Alpha spectrometer with Platinum-ATR module. A Horiba XploRA Plus Raman microscope with a 638 nm laser (power: ≤150 mW) was used to obtain all Raman spectra. The power of the laser was adjusted for each sample using a filter to prevent sample decomposition. Elemental microanalyses were carried out by Mr Martin Jennings at the Micro Analytical Laboratory, Department of Chemistry, The University of Manchester. Complexes 1–3 were prepared as described previously [53,54,55].

3.2. Quantum Chemical Calculations

Geometry optimisations for ThRe and ThRu were performed using coordinates derived from their respective crystal structures as the starting points. No constraints were imposed on the structures during the geometry optimisations. The calculations were performed using the Amsterdam Density Functional (ADF) suite version 2017 with standard convergence criteria [64,65]. The DFT geometry optimisations employed Slater type orbital (STO) triple-ζ-plus polarisation all electron basis sets (from the Dirac and ZORA/TZP database of the ADF suite). Scalar relativistic approaches (spin-orbit neglected) were used within the ZORA Hamiltonian [66,67,68] for the inclusion of relativistic effects, and the local density approximation (LDA) with the correlation potential due to Vosko et al. was used in all of the calculations [69]. Generalised gradient approximation corrections were performed using the functionals of Becke and Perdew [70,71]. MOLEKEL [72] was used to prepare the three-dimensional plots of the electron density. Frequencies were computed using the analytical frequencies routine in ADF.

3.3. Preparation of [Th(TrenDMBS)ReCp2] (ThRe)

Toluene (20 mL) was added to a precooled (–78 °C) mixture of 1 (0.359 g, 0.25 mmol) and 2 (0.154 g, 0.5 mmol). The resultant pale-yellow suspension was allowed to warm to RT and then stirred for 16 h, giving a dark yellow solution. Volatiles were removed in vacuo, and the resulting brown solid was extracted into toluene, concentrated to 5 mL, and cooled to –30 °C to afford ThRe as pale brown crystals. Yield: 0.260 g, 71%. Anal. Calc’d for C34H67N4ReSi3Th: C 39.48; H 6.53; N 5.42%. Found: C 39.48; H 6.67; N 5.40%. 1H NMR (C6D6) δ: 4.42 (10H, s, Cp-H), 3.21 (6H, t, CH2), 2.45 (6H, t, CH2), 1.09 (27H, s, CH3), 0.38 (18H, s, CH3) ppm. 13C{1H} NMR (C6D6) δ: 67.93 (CH2), 46.65 (CH2), 28.90 (C-CH3), 21.96 (C-CH3), −1.78 (Si-CH3) ppm. FTIR ν/cm−1 (ATR): 2950 (w), 2850 (m), 1462 (m), 1245 (m), 1058 (m), 929 (s), 805 (s). Raman ν/cm−1 (Neat, ≤15 mW): 3103 (m, br), 2952 (m), 2853 (m), 1084 (s), 567 (m), 338 (s), 136 (w), 103 (w), and 63 (s).

3.4. Preparation of [Th(TrenDMBS)RuCp-(CO)2] (ThRu)

Benzene (10 mL) was added to a mixture of 1 (0.210 g, 0.15 mmol) and 3 (0.067 g, 0.30 mmol) in a glovebox. The resultant light brown solution quickly gave a pale-yellow precipitate, which was separated from the solution, washed with pentane (2 × 5 mL), and allowed to dry. The solid was extracted into minimal THF, which afforded ThRu as pale brown crystals; these crystals were found to be the benzene solvate ThRu.C6H6, but drying under vacuum results in their desolvation, as reflected by the other characterisation data. Yield: 0.152 g, 62 %. Anal. Calc’d for C31H62N4O2RuSi3Th: C 39.60; H 6.65; N 5.96%. Found: C 39.45; H 6.70; N 5.36%. 1H NMR (C6D6) δ: 5.08 (5H, s, Cp-H), 3.20 (6H, t, JHH = 4.96 Hz, CH2), 2.38 (6H, t, JHH = 4.96 Hz, CH2), 1.04 (27H, s, C-CH3), 0.51 (18H, s, Si-CH3) ppm. 13C{1H} NMR (C6D6) δ: 86.52 (CH), 64.39 (CH2), 47.46 (CH2), 28.51 (C-CH3), 21.41 (C-CH3), −3.25 (Si-CH3) ppm. FTIR ν/cm−1 (ATR): 2924 (w), 2848 (w), 1943 (s), 1869 (s), 1462 (w), 1248 (m), 1072 (m), 936 (m). Raman ν/cm−1 (Neat, ≤15 mW): 2957 (m), 2853 (s), 1935 (s), 1869 (s), 1200 (s), 1102 (s), 567 (s), 518 (s), 303 (s), 112 (m), and 73 (s).

4. Conclusions

To conclude, we have prepared two new triamidoamine complexes of Th that possess Th-Re and Th-Ru bonds using an alkane elimination strategy. The Th-Re bond in ThRe is the first structurally authenticated example of a molecular Th-Re bond, and the Th-Ru bond in ThRu is only the second example of a structurally characterised Th-Ru bond, with the other example reported 36 years ago. Structural, spectroscopic, and computational characterisation of these two complexes, along with comparisons to previously reported isostructural U-Re and U-Ru complexes, has permitted an analysis of these metal–metal bonds. In-line with the current understanding, these Th-metal bonds are like-for-like more ionic than the U-congeners. By being able to experimentally validate the calculations using spectroscopic vibrational data, as well as gauging the strength of these metal–metal bonds indirectly using the carbonyls as reporters, we have been able to probe with certainty the Th-Re and Th-Ru bonds directly using Raman spectroscopy.

Supplementary Materials

The following are available online at https://0-www-mdpi-com.brum.beds.ac.uk/article/10.3390/inorganics9050030/s1, Table S1: Final Coordinates and Energy from a Single Point Energy Calculation on Geometry Optimised ThRe, Table S2: Final Coordinates and Energy from a Single Point Energy Calculation on Geometry Optimised ThRu. CIFs and checkCIF output files for ThRe and ThRu.

Author Contributions

Conceptualisation, S.T.L.; methodology, S.T.L. and J.P.A.O.; formal analysis, J.P.A.O. and A.J.W.; investigation, J.P.A.O.; data curation, A.J.W.; writing—original draft preparation, S.T.L.; writing—review and editing, S.T.L., J.P.A.O., and A.J.W.; supervision, S.T.L.; project administration, S.T.L.; funding acquisition, S.T.L. All authors have read and agreed to the published version of the manuscript.

Funding

We thank the Royal Society (UF071260, UF110005, and RG080285), EPSRC (EP/G051763/1, EP/M027015/1, and EP/P001386/1), ERC (StG23921 and CoG612724), and The University of Manchester for funding and support, and the Alexander von Humboldt Foundation for the award of a Friedrich Wilhelm Bessel Research Award to S.T.L.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The crystallographic data for ThRe and ThRu have been deposited with the Cambridge Crystallographic Data Centre, CCDC numbers 2076926 and 2076927, and all other data are available from the authors on request.

Conflicts of Interest

The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

References

  1. Cotton, F.A.; Murillo, C.A.; Walton, R.A. (Eds.) Multiple Bonds between Metal Atoms, 3rd ed.; Springer: New York, NY, USA, 2005. [Google Scholar]
  2. Parkin, G. (Ed.) Metal-Metal Bonding; Springer: New York, NY, USA, 2010. [Google Scholar]
  3. Liddle, S.T. (Ed.) Molecular Metal-Metal Bonds: Compounds, Synthesis, Properties; Wiley VCH: Weinheim, Germany, 2015. [Google Scholar]
  4. Wheatley, N.; Kalck, P. Structure and Reactivity of Early-Late Heterobimetallic Complexes. Chem. Rev. 1999, 99, 3379–3420. [Google Scholar] [CrossRef] [PubMed]
  5. Chipman, J.A.; Berry, J.F. Paramagnetic Metal-Metal Bonded Heterometallic Complexes. Chem. Rev. 2020, 120, 2409–2447. [Google Scholar] [CrossRef] [PubMed]
  6. Zhang, X.; Wang, Y.; Morales-Martínez, R.; Zhong, J.; de Graaf, C.; Rodríguez-Fortea, A.; Poblet, J.M.; Echegoyen, L.; Feng, L.; Chen, N. U2@Ih(7)-C80: Crystallographic Characterization of a Long-Sought Dimetallic Actinide Endohedral Fullerene. J. Am. Chem. Soc. 2018, 140, 3907–3915. [Google Scholar] [CrossRef] [PubMed]
  7. Liddle, S.T.; Mills, D.P. Metal-Metal Bonds in f-Element Chemistry. Dalton Trans. 2009, 5592–5605. [Google Scholar] [CrossRef]
  8. Oelkers, B.; Butovskii, M.V.; Kempe, R. f-Element-Metal Bonding and the Use of the Bond Polarity to Build Molecular Intermetalloids. Chem. Eur. J. 2012, 18, 13566–13579. [Google Scholar] [CrossRef]
  9. Patel, D.; Liddle, S.T. f-Element-Metal Bond Chemistry. Rev. Inorg. Chem. 2012, 32, 1–22. [Google Scholar] [CrossRef]
  10. Butovskii, M.V.; Kempe, R. Rare earth-metal bonding in molecular compounds: Recent advances, challenges, and perspectives. New J. Chem. 2015, 39, 7544–7558. [Google Scholar] [CrossRef]
  11. Réant, B.L.L.; Liddle, S.T.; Mills, D.P. f-Element silicon and heavy tetrel chemistry. Chem. Sci. 2020, 11, 10871–10886. [Google Scholar] [CrossRef]
  12. Ayres, A.J.; Zegke, M.; Ostrowski, J.P.A.; Tuna, F.; McInnes, E.J.L.; Wooles, A.J.; Liddle, S.T. Actinide-transition metal bonding in heterobimetallic uranium− and thorium−molybdenum paddlewheel complexes. Chem. Commun. 2018, 54, 13515–13518. [Google Scholar] [CrossRef] [Green Version]
  13. Sternal, R.S.; Marks, T.J. Actinide-to-transition metal bonds. Synthesis, characterization, and properties of metal-metal bonded systems having the tris(cyclopentadienyl)actinide fragment. Organometallics 1987, 6, 2621–2623. [Google Scholar] [CrossRef]
  14. Nolan, S.P.; Porchia, M.; Marks, T.J. Organo-f-element thermochemistry. Actinide-Group 14 element and actinide-transition-element bond disruption enthalpies and stoichiometric/catalytic chemical implications thereof in heterobimetallic tris(cyclopentadienyl)uranium(IV) compounds. Organometallics 1991, 10, 1450–1457. [Google Scholar] [CrossRef]
  15. Bucaille, A.; Le Borgne, T.; Ephritikhine, M.; Daran, J.C. Synthesis and X-ray Crystal Structure of a Urana[1]ferrocenophane, the First Tris(1,1′-ferrocenylene) Metal Compound. Organometallics 2000, 19, 4912–4914. [Google Scholar] [CrossRef]
  16. Monreal, M.J.; Carver, C.T.; Diaconescu, P.L. Redox processes in a uranium bis(1,1′-diamidoferrocene) complex. Inorg. Chem. 2007, 46, 7226–7228. [Google Scholar] [CrossRef]
  17. Monreal, M.J.; Diaconescu, P.L. A weak interaction between iron and uranium in uranium alkyl complexes supported by ferrocene diamide ligands. Organometallics 2008, 27, 1702–1706. [Google Scholar] [CrossRef]
  18. Fortier, S.; Aguilar-Calderon, J.R.; Vlaisavljevich, B.; Metta-Magana, A.J.; Goos, A.G.; Botez, C.E. An N-Tethered Uranium(III) Arene Complex and the Synthesis of an Unsupported U-Fe Bond. Organometallics 2017, 36, 4591–4599. [Google Scholar] [CrossRef]
  19. Sternal, R.S.; Brock, C.P.; Marks, T.J. Metal-metal bonds involving actinides. Synthesis and characterization of a complex having an unsupported actinide to transition metal bond. J. Am. Chem. Soc. 1985, 107, 8270–8272. [Google Scholar] [CrossRef]
  20. Gardner, B.M.; Patel, D.; Cornish, A.D.; McMaster, J.; Lewis, W.; Blake, A.J.; Liddle, S.T. The Nature of Unsupported Uranium-Ruthenium Bonds: A Combined Experimental and Theoretical Study. Chem. Eur. J. 2011, 17, 11266–11273. [Google Scholar] [CrossRef]
  21. Gardner, B.M.; McMaster, J.; Lewis, W.; Liddle, S.T. Synthesis and structure of {N(CH2CH2NSiMe3)3}URe(η5-C5H5)2: A heterobimetallic complex with an unsupported uranium-rhenium bond. Chem. Commun. 2009, 2851–2853. [Google Scholar] [CrossRef]
  22. Gardner, B.M.; McMaster, J.; Moro, F.; Lewis, W.; Blake, A.J.; Liddle, S.T. An Unsupported Uranium-Rhenium Complex Prepared by Alkane Elimination. Chem. Eur. J. 2011, 17, 6909–6912. [Google Scholar] [CrossRef]
  23. Patel, D.; King, D.M.; Gardner, B.M.; McMaster, J.; Lewis, W.; Blake, A.J.; Liddle, S.T. Structural and theoretical insights into the perturbation of uranium-rhenium bonds by dative Lewis base ancillary ligands. Chem. Commun. 2011, 47, 295–297. [Google Scholar] [CrossRef]
  24. Patel, D.; Moro, F.; McMaster, J.; Lewis, W.; Blake, A.J.; Liddle, S.T. A Formal High Oxidation State Inverse-Sandwich Diuranium Complex: A New Route to f-Block-Metal Bonds. Angew. Chem. Int. Ed. 2011, 50, 10388–10392. [Google Scholar] [CrossRef]
  25. Napoline, J.W.; Kraft, S.J.; Matson, E.M.; Fanwick, P.E.; Bart, S.C.; Thomas, C.M. Tris(phosphinoamide)-Supported Uranium-Cobalt Heterobimetallic Complexes Featuring Co → U Dative Interactions. Inorg. Chem. 2013, 52, 12170–12177. [Google Scholar] [CrossRef] [PubMed]
  26. Ward, A.L.; Lukens, W.W.; Lu, C.C.; Arnold, J. Photochemical Route to Actinide-Transition Metal Bonds: Synthesis, Characterization and Reactivity of a Series of Thorium and Uranium Heterobimetallic Complexes. J. Am. Chem. Soc. 2014, 136, 3647–3654. [Google Scholar] [CrossRef] [Green Version]
  27. Lu, E.; Wooles, A.J.; Gregson, M.; Cobb, P.J.; Liddle, S.T. A Very Short Uranium(IV)-Rhodium(I) Bond with Net Double-Dative Bonding Character. Angew. Chem. Int. Ed. 2018, 57, 6587–6591. [Google Scholar] [CrossRef]
  28. Hlina, J.A.; Wells, J.A.L.; Pankhurst, J.R.; Love, J.B.; Arnold, P.L. Uranium rhodium bonding in heterometallic complexes. Dalton Trans. 2017, 46, 5540–5545. [Google Scholar] [CrossRef] [Green Version]
  29. Geng, G.; Zhang, M.; Wang, P.; Wang, S.; Maron, L.; Zhu, C. Identification of a uranium-rhodium triple bond in a heterometallic cluster. Proc. Natl. Acad. Sci. USA 2019, 116, 17654–17658. [Google Scholar]
  30. Ritchey, J.M.; Zozulin, A.J.; Wrobleski, D.A.; Ryan, R.R.; Wasserman, H.J.; Moody, D.C.; Paine, R.T. An organothorium-nickel phosphido complex with a short thorium-nickel distance. The structure of Th(η5-C5Me5)2(μ-PPh2)2Ni(C)(CO)2. J. Am. Chem. Soc. 1985, 107, 501–503. [Google Scholar] [CrossRef]
  31. Hlina, J.A.; Pankhurst, J.R.; Kaltsoyannis, N.; Arnold, P.L. Metal−Metal Bonding in Uranium−Group 10 Complexes. J. Am. Chem. Soc. 2016, 138, 3333–3345. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  32. Camp, C.; Toniolo, D.; Andrez, J.; Pecaut, J.; Mazzanti, M. A versatile route to homo- and hetero-bimetallic 5f-5f and 3d-5f complexes supported by a redox active ligand framework. Dalton Trans. 2017, 46, 11145–11148. [Google Scholar] [CrossRef] [Green Version]
  33. Kozimor, S.A.; Bartlett, B.M.; Rinehart, J.D.; Long, J.R. Magnetic exchange coupling in chloride-bridged 5f-3d heterometallic complexes generated via insertion into a Uranium(IV) dimethylpyrazolate dimer. J. Am. Chem. Soc. 2007, 129, 10672–10674. [Google Scholar] [CrossRef]
  34. Feng, G.; Zhang, M.; Shao, S.; Wang, X.; Wang, S.; Maron, L.; Zhu, C. Transition-metal-bridged bimetallic clusters with multiple uranium-metal bonds. Nat. Chem. 2019, 11, 248–253. [Google Scholar] [CrossRef] [PubMed]
  35. Feng, G.; McCabe, K.N.; Wang, S.; Maron, L.; Zhu, C. Construction of heterometallic clusters with multiple uranium-metal bonds by using dianionic nitrogen-phosphorus ligands. Chem. Sci. 2020, 11, 7585–7592. [Google Scholar] [CrossRef] [Green Version]
  36. Hay, P.J.; Ryan, R.R.; Salazar, K.V.; Wrobleski, D.A.; Sattelberger, A.P. Synthesis and x-ray structure of (C5Me5)2Th(μ-PPh2)2Pt(PMe3): A complex with a thorium-platinum bond. J. Am. Chem. Soc. 1986, 108, 313–315. [Google Scholar] [CrossRef]
  37. Leverd, P.C.; Lance, M.; Nierlich, M.; Vigner, J.; Ephritikhine, M. Synthesis and crystal structure of homoleptic uranium hexathiolates: [NEt2H2]2[U(SPh)6] and [(Ph3P)Cu(μ-SPh)3-U(μ-SPh)3Cu(PPh3)]. J. Chem. Soc. Dalton Trans. 1994, 3563–3567. [Google Scholar] [CrossRef]
  38. Yang, P.; Zhou, E.; Hou, G.; Zi, G.; Ding, W.; Walter, M.D. Experimental and Computational Studies on the Formation of Thorium-Copper Heterobimetallics. Chem. Eur. J. 2016, 22, 13845–13849. [Google Scholar] [CrossRef]
  39. Fortier, S.; Walensky, J.R.; Wu, G.; Hayton, T.W. High-Valent Uranium Alkyls: Evidence for the Formation of UVI(CH2SiMe3)6. J. Am. Chem. Soc. 2011, 133, 11732–11743. [Google Scholar] [CrossRef]
  40. Minasian, S.G.; Krinsky, J.L.; Williams, V.A.; Arnold, J. A heterobimetallic complex with an unsupported Uranium(III)-Aluminum(I) bond: (CpSiMe3)3U-AlCp* (Cp* = C5Me5). J. Am. Chem. Soc. 2008, 130, 10086–10087. [Google Scholar] [CrossRef] [Green Version]
  41. Minasian, S.G.; Krinsky, J.L.; Rinehart, J.D.; Copping, R.; Tyliszczak, T.; Janousch, M.; Shuh, D.K.; Arnold, J. A Comparison of 4f vs 5f Metal-Metal Bonds in (CpSiMe3)3M-ECp* (M = Nd, U; E = Al, Ga; Cp* = C5Me5): Synthesis, Thermodynamics, Magnetism, and Electronic Structure. J. Am. Chem. Soc. 2009, 131, 13767–13783. [Google Scholar] [CrossRef]
  42. Liddle, S.T.; McMaster, J.; Mills, D.P.; Blake, A.J.; Jones, C.; Woodul, W.D. σ and π Donation in an Unsupported Uranium-Gallium Bond. Angew. Chem. Int. Ed. 2009, 48, 1077–1080. [Google Scholar] [CrossRef]
  43. Diaconescu, P.L.; Odum, A.L.; Agapie, T.; Cummins, C.C. Uranium-Group 14 Element Single Bonds: Isolation and Characterization of a Uranium(IV) Silyl Species. Organometallics 2001, 20, 4993–4995. [Google Scholar] [CrossRef] [Green Version]
  44. Porchia, M.; Brianese, N.; Casellato, U.; Ossola, F.; Rossetto, G.; Zanella, P. Tri(η-cyclopentadienyl)uranium(IV) silyl and siloxide compounds: Crystal structure of [U(η5-C5H5)3(OSiPh3)]: Insertion of Isocyanide into a uranium-silicon bond. J. Chem. Soc. Dalton Trans. 1989, 677–681. [Google Scholar] [CrossRef]
  45. Brackbill, I.J.; Douair, I.; Lussier, D.J.; Boreen, M.A.; Maron, L.; Arnold, J. Synthesis and Structure of Uranium-Silylene Complexes. Chem. Eur. J. 2020, 26, 2360–2364. [Google Scholar] [CrossRef]
  46. Réant, B.L.L.; Berryman, V.E.J.; Seed, J.A.; Basford, A.R.; Formanuik, A.; Wooles, A.J.; Kaltsoyannis, N.; Liddle, S.T.; Mills, D.P. Polarised Covalent Thorium(IV)- and Uranium(IV)-Silicon Bonds. Chem. Commun. 2020, 56, 12620–12623. [Google Scholar] [CrossRef]
  47. Porchia, M.; Ossola, F.; Rossetto, G.; Zanella, P.; Brianese, N. Synthesis of triscyclopentadienyl(triphenylgermyl)uranium and facile isonitrile insertion into the uranium-germanium bond. J. Chem. Soc. Chem. Commun. 1987, 550–551. [Google Scholar] [CrossRef]
  48. Porchia, M.; Casellato, U.; Ossola, F.; Rossetto, G.; Zanella, P.; Graziani, R. Synthesis and crystal structure of triscyclopentadienyl-(triphenyltin)uranium: The first example of a uranium-tin bond. J. Chem. Soc. Chem. Commun. 1986, 1034–1035. [Google Scholar] [CrossRef]
  49. Winston, M.S.; Batista, E.R.; Yang, P.; Tondreau, A.M.; Boncella, J.M. Extending Stannyl Anion Chemistry to the Actinides: Synthesis and Characterization of a Uranium−Tin Bond. Inorg. Chem. 2016, 55, 5534–5539. [Google Scholar] [CrossRef]
  50. Rookes, T.M.; Wildman, E.P.; Balazs, G.; Gardner, B.M.; Wooles, A.J.; Gregson, M.; Tuna, F.; Scheer, M.; Liddle, S.T. Actinide-Pnictide (An-Pn) Bonds Spanning Non-Metal, Metalloid, and Metal Combinations (An = U, Th; Pn = P, As, Sb, Bi). Angew. Chem. Int. Ed. 2018, 57, 1332–1336. [Google Scholar] [CrossRef] [Green Version]
  51. Lichtenberger, N.; Wilson, R.J.; Eulenstein, A.R.; Massa, W.; Clérac, R.; Weigend, F.; Dehnen, S. Main Group Metal-Actinide Magnetic Coupling and Structural Response Upon U4+ Inclusion into Bi, Tl/Bi, or Pb/Bi Cages. J. Am. Chem. Soc. 2016, 138, 9033–9036. [Google Scholar] [CrossRef] [Green Version]
  52. Eulenstein, A.R.; Franzke, Y.J.; Lichtenberger, N.; Wilson, R.J.; Deubner, H.L.; Kraus, F.; Clérac, R.; Weigand, F.; Dehnen, S. Substantial π-aromaticity in the anionic heavy-metal cluster [Th@Bi12]4−. Nat. Chem. 2021, 13, 149–155. [Google Scholar] [CrossRef]
  53. Gardner, B.M.; Lewis, W.; Blake, A.J.; Liddle, S.T. Thorium Triamidoamine Complexes: Synthesis of an Unusual Dinuclear Tuck-In-Tuck-Over Thorium Metallacycle Featuring the Longest Known Thorium-σ-Alkyl Bond. Organometallics 2015, 34, 2386–2394. [Google Scholar] [CrossRef]
  54. Green, M.L.H.; Pratt, L.; Wilkinson, G. Biscyclopentadienylrhenium hydride. J. Chem. Soc. 1958, 3916–3922. [Google Scholar] [CrossRef]
  55. Karunananda, M.K.; Mankad, N.P. Heterobimetalluc H2 Addition and Alkene/Alkane Elimination Reactions Related to the Mechanism of E-Selective Alkyne Semihydrogenation. Organometallics 2017, 36, 220–227. [Google Scholar] [CrossRef]
  56. Pyykkö, P. Additive Covalent Radii for Single-, Double-, and Triple-Bonded Molecules and Tetrahedrally Bonded Crystals: A Summary. J. Phys. Chem. A 2015, 119, 2326–2337. [Google Scholar] [CrossRef] [PubMed]
  57. Ostrowski, J.P.A.; Atkinson, B.E.; Doyle, L.R.; Wooles, A.J.; Kaltsoyannis, N.; Liddle, S.T. The Ditungsten Decacarbonyl Dianion. Dalton Trans. 2020, 49, 9330–9355. [Google Scholar] [CrossRef]
  58. Oxford Diffraction/Agilent Technologies UK Ltd. CrysAlisPRO Version 39.46; Oxford Diffraction/Agilent Technologies UK Ltd.: Yarnton, UK, 2013. [Google Scholar]
  59. Sheldrick, G.M. SHELXT—Integrated space-group and crystal structure determination. Acta Cryst. Sect. A 2015, 71, 3–8. [Google Scholar] [CrossRef] [Green Version]
  60. Sheldrick, G.M. Crystal structure refinement with SHELXL. Acta Cryst. Sect. C 2015, 71, 3–8. [Google Scholar] [CrossRef]
  61. Dolomanov, O.V.; Bourhis, L.J.; Gildea, R.J.; Howard, J.A.K.; Puschmann, H. OLEX2: A complete structure solution, refinement and analysis program. J. Appl. Cryst. 2009, 42, 339–341. [Google Scholar] [CrossRef]
  62. Farugia, L.J. WinGX and ORTEP for Windows: An update. J. Appl. Cryst. 2012, 45, 849–854. [Google Scholar] [CrossRef]
  63. Persistence of Vision Pty Ltd. Persistence of Vision (TM) Raytracer; Persistence of Vision Pty. Ltd.: Williamstown, Melbourne, VIC, Australia, 2020. [Google Scholar]
  64. Fonseca Guerra, C.; Snijders, J.G.; Te Velde, G.; Baerends, E.J. Towards an order-N DFT Method. Theor. Chem. Acc. 1998, 99, 391–403. [Google Scholar] [CrossRef]
  65. Te Velde, G.; Bickelhaupt, F.M.; Van Gisbergen, S.J.; Fonseca Guerra, A.C.; Baerends, E.J.; Snijders, J.G.; Ziegler, T. Chemistry with ADF. J. Comput. Chem. 2001, 22, 931–967. [Google Scholar] [CrossRef]
  66. Van Lenthe, E.; Baerends, E.J.; Snijders, J.G. Relativistic regular two-component Hamiltonians. J. Chem. Phys. 1993, 99, 4597–4610. [Google Scholar] [CrossRef]
  67. Van Lenthe, E.; Baerends, E.J.; Snijders, J.G. Relativistic total energy using regular approximations. J. Chem. Phys. 1994, 101, 9783–9792. [Google Scholar] [CrossRef]
  68. Van Lenthe, E.; Ehlers, A.E.; Baerends, E.J. Geometry optimization in the Zero Order Regular Approximation for relativistic effects. J. Chem. Phys. 1999, 110, 8943–8953. [Google Scholar] [CrossRef] [Green Version]
  69. Vosko, S.H.; Wilk, L.; Nusair, M. Accurate spin-dependent electron liquid correlation energies for local spin density calculations: A critical analysis. Can. J. Phys. 1980, 58, 1200–1211. [Google Scholar] [CrossRef] [Green Version]
  70. Becke, A.D. Density-functional exchange-energy approximation with correct asymptotic behaviour. Phys. Rev. A 1988, 38, 3098. [Google Scholar] [CrossRef]
  71. Perdew, J.P. Density-functional approximation for the correlation energy of the inhomogeneous electron gas. Phys. Rev. B 1986, 33, 8822. [Google Scholar] [CrossRef]
  72. Portmann, S.; Luthi, H.P. MOLEKEL: An interactive molecular graphics tool. Chimia 2000, 54, 766–770. [Google Scholar]
Inorganics 09 00030 sch001 550
Scheme 1. Synthesis of ThRe and ThRu from 1, 2, and 3, respectively.
Scheme 1. Synthesis of ThRe and ThRu from 1, 2, and 3, respectively.
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Inorganics 09 00030 g001 550
Figure 1. Solid-state structures of (a) ThRe and (b) ThRu at 150 K with displacement ellipsoids set to 30%. Hydrogen atoms, disorder components, and benzene lattice solvent for ThRu are omitted for clarity.
Figure 1. Solid-state structures of (a) ThRe and (b) ThRu at 150 K with displacement ellipsoids set to 30%. Hydrogen atoms, disorder components, and benzene lattice solvent for ThRu are omitted for clarity.
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Figure 2. (a) HOMO-1 (252, −4.054 eV) of ThRe. (b) HOMO-2 (251, −4.161 eV) of ThRe. (c) HOMO (234, −4.409 eV) of ThRu. Hydrogen atoms are omitted for clarity.
Figure 2. (a) HOMO-1 (252, −4.054 eV) of ThRe. (b) HOMO-2 (251, −4.161 eV) of ThRe. (c) HOMO (234, −4.409 eV) of ThRu. Hydrogen atoms are omitted for clarity.
Inorganics 09 00030 g002
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Ostrowski, J.P.A.; Wooles, A.J.; Liddle, S.T. Synthesis and Characterisation of Molecular Polarised-Covalent Thorium-Rhenium and -Ruthenium Bonds. Inorganics 2021, 9, 30. https://0-doi-org.brum.beds.ac.uk/10.3390/inorganics9050030

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Ostrowski JPA, Wooles AJ, Liddle ST. Synthesis and Characterisation of Molecular Polarised-Covalent Thorium-Rhenium and -Ruthenium Bonds. Inorganics. 2021; 9(5):30. https://0-doi-org.brum.beds.ac.uk/10.3390/inorganics9050030

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Ostrowski, Joseph P. A., Ashley J. Wooles, and Stephen T. Liddle. 2021. "Synthesis and Characterisation of Molecular Polarised-Covalent Thorium-Rhenium and -Ruthenium Bonds" Inorganics 9, no. 5: 30. https://0-doi-org.brum.beds.ac.uk/10.3390/inorganics9050030

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