metal-organic compounds
Di-μ-chlorido-bis[chloridobis(dimethyl sulfoxide)dioxidouranium(VI)]
aResearch Laboratory for Nuclear Reactors, Tokyo Institute of Technology, 2-12-1-N1-34, O-okayama, Meguro-ku, Tokyo 152-8550, Japan
*Correspondence e-mail: yikeda@nr.titech.ac.jp
In the 2Cl4O4(C2H6OS)4], the compound has a centrosymmetric dimeric structure bridged by two chloride anions. Each UVI atom is seven-coordinate in a pentagonal-bipyramidal geometry. In the equatorial plane of the uranyl unit there are two O atoms from non-adjacent dimethyl and three chloride ions (of which two chlorides are bridging). The compound is of interest as an anhydrous starting material of the uranyl(VI) ion.
of the title compound, [URelated literature
For related structures, see: Berthet et al. (2000); Charpin et al. (1987); Rebizant et al. (1987); Wilkerson et al. (1999). For the synthesis, see: Calderazzo et al. (1997); Berthet et al. (2000).
Experimental
Crystal data
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Refinement
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Data collection: PROCESS-AUTO (Rigaku/MSC, 2000-2006); cell PROCESS-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 2000-2006); program(s) used to solve structure: SIR92 (Altomare et al. 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPIII (Farrugia, 1997); software used to prepare material for publication: CrystalStructure.
Supporting information
https://doi.org/10.1107/S1600536807064264/xu2386sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536807064264/xu2386Isup2.hkl
Uranium(VI) trioxide was dissolved in 5 M hydrochloric acid solution. With heating and vigrous stirring, 2 molar amount of silver powder was added in the HCl aq. After 30 min, the mixture was cooled to room temperature. The insoluble residure of AgCl was removed by filtration. Small portion (ca 1 ml) of this filtrate was separated in a test tube. In this sample, some drops of dimethyl sulfoxide was added. The mixture was allowed to the air. After several days, yellow crystals of the title compound deposited.
H atoms were placed in calculated positions with C—H = 0.98 Å and torsion angles were refined to fit the electron density, with Uiso(H) = 1.2Ueq(C). The highest peak in the final difference Fourier map is 0.91 Å apart from the U atom.
The title compound (I) was unexpectedly obtained from a hydrochloric acid aqueous solution containing U4+ and dimethyl sulfoxide (DMSO). It is reasonable to consider that I was formed by aerobic oxidation of U4+ to UO22+.
The title compound I has a dimeric structure which is bridged by two µ-Cl- between UO2Cl(DMSO)2 fragments as shown in Fig. 1. There is an inversion center in the molecular structure of I. Each U atom is seven-coordinated in a pentagonal-bipyramidal geometry. Two O atoms are at the axial positions [mean U=Oyl = 1.75 (1) Å] (Table 1). In the equatorial plane of each U, there are three Cl- ions; two of them act as µ-Cl- to bridge the U atoms in I [mean U–Clbridge = 2.88 (3) Å], and the remaining Cl- is placed at the position independent of the bridge formation [U–Clnon-bridge = 2.686 (2) Å]. The DMSO molecules in the equatorial plane coordinates to U through its O, and are non-adjacent [mean U–ODMSO = 2.35 (1) Å]. Deviations of Cl- and O of DMSO from the mean equatorial plane are within 0.15 Å. Interatomic distances between U(1)···U(1)i and µ-Cl(1)···µ-Cl(1)i [symmetry code: (i) -x + 2, -y + 1, -z + 1] are 4.7669 (3) and 3.221 (3) Å, respectively, which indicate no interatomic interaction in each pair. These structural features of I are similar to that of [UO2Cl(THF)2]2(µ-Cl)2 (THF = tetrahydrofuran) reported by Charpin et al. (1987).
Previously, some anhydrous uranyl(VI) salts, UO2Br2(THF)3, UO2Cl2(THF)3, [UO2Cl(THF)2]2(µ-Cl)2, and UO2(CF3SO3)2L3 (L = THF, pyridine), were reported (Rebizant et al. 1987, Wilkerson et al. 1999, Charpin et al. 1987, Berthet et al. 2000, respectively). In syntheses of water-sensitive uranyl(VI) compounds, e.g.,
and anhydrous starting materials must be used. On the other hand, THF is not very stable, and may be decomposed by its polymerization in presence of a strong acid, e.g. CF3SO3H (Calderazzo et al. 1997 and Berthet et al. 2000). Compound I also has simple composition, i.e., consisting only of UO22+, Cl-, and DMSO. The use of DMSO insead of THF expands the number of choices of the anhydrous uranyl(VI) salts as the starting material.For related structures, see: Berthet et al. (2000); Charpin et al. (1987); Rebizant et al. (1987); Wilkerson et al. (1999). For the synthesis, see: Calderazzo et al. (1997); Berthet et al. (2000).
Data collection: PROCESS-AUTO (Rigaku/MSC, 2000-2006); cell
PROCESS-AUTO (Rigaku/MSC, 2000-2006); data reduction: CrystalStructure (Rigaku/MSC, 2000-2006); program(s) used to solve structure: SIR92 (Altomare et al. 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPIII (Farrugia, 1997); software used to prepare material for publication: CrystalStructure (Rigaku/MSC).[U2Cl4O4(C2H6OS)4] | F(000) = 904 |
Mr = 994.37 | Dx = 2.648 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71075 Å |
Hall symbol: -P 2ybc | Cell parameters from 10519 reflections |
a = 9.172 (3) Å | θ = 3.1–27.5° |
b = 12.833 (4) Å | µ = 13.76 mm−1 |
c = 10.691 (2) Å | T = 173 K |
β = 97.72 (2)° | Block, yellow |
V = 1247.0 (6) Å3 | 0.33 × 0.21 × 0.15 mm |
Z = 2 |
Rigaku R-AXIS RAPID IP diffractometer | 2849 independent reflections |
Radiation source: fine-focus sealed tube | 2330 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.084 |
Detector resolution: 10.00 pixels mm-1 | θmax = 27.5°, θmin = 3.2° |
ω scans | h = −11→11 |
Absorption correction: multi-scan (Higashi, 1999) | k = −16→15 |
Tmin = 0.051, Tmax = 0.128 | l = −13→13 |
10244 measured reflections |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.043 | H-atom parameters constrained |
wR(F2) = 0.111 | w = 1/[σ2(Fo2) + (0.0595P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.10 | (Δ/σ)max = 0.001 |
2849 reflections | Δρmax = 2.54 e Å−3 |
120 parameters | Δρmin = −2.25 e Å−3 |
0 restraints | Extinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0012 (2) |
[U2Cl4O4(C2H6OS)4] | V = 1247.0 (6) Å3 |
Mr = 994.37 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 9.172 (3) Å | µ = 13.76 mm−1 |
b = 12.833 (4) Å | T = 173 K |
c = 10.691 (2) Å | 0.33 × 0.21 × 0.15 mm |
β = 97.72 (2)° |
Rigaku R-AXIS RAPID IP diffractometer | 2849 independent reflections |
Absorption correction: multi-scan (Higashi, 1999) | 2330 reflections with I > 2σ(I) |
Tmin = 0.051, Tmax = 0.128 | Rint = 0.084 |
10244 measured reflections |
R[F2 > 2σ(F2)] = 0.043 | 0 restraints |
wR(F2) = 0.111 | H-atom parameters constrained |
S = 1.10 | Δρmax = 2.54 e Å−3 |
2849 reflections | Δρmin = −2.25 e Å−3 |
120 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > 2σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
U1 | 0.78418 (3) | 0.51860 (2) | 0.35047 (3) | 0.02280 (14) | |
Cl1 | 0.9986 (2) | 0.37721 (17) | 0.4687 (2) | 0.0309 (5) | |
Cl2 | 0.5528 (3) | 0.5489 (2) | 0.1718 (2) | 0.0381 (5) | |
S1 | 0.7780 (2) | 0.28472 (17) | 0.1748 (2) | 0.0279 (5) | |
S2 | 0.8069 (3) | 0.78684 (18) | 0.3045 (2) | 0.0319 (5) | |
O1 | 0.6738 (8) | 0.4945 (5) | 0.4683 (6) | 0.0310 (14) | |
O2 | 0.8996 (8) | 0.5398 (5) | 0.2345 (6) | 0.0327 (15) | |
O3 | 0.7203 (7) | 0.3496 (5) | 0.2783 (5) | 0.0280 (13) | |
O4 | 0.7311 (7) | 0.6977 (5) | 0.3661 (5) | 0.0296 (14) | |
C1 | 0.7963 (11) | 0.1587 (7) | 0.2424 (9) | 0.037 (2) | |
H1A | 0.8810 | 0.1575 | 0.3089 | 0.044* | |
H1B | 0.8112 | 0.1077 | 0.1771 | 0.044* | |
H1C | 0.7068 | 0.1412 | 0.2788 | 0.044* | |
C2 | 0.6207 (11) | 0.2632 (8) | 0.0621 (8) | 0.038 (2) | |
H2A | 0.5958 | 0.3275 | 0.0145 | 0.045* | |
H2B | 0.5377 | 0.2424 | 0.1055 | 0.045* | |
H2C | 0.6416 | 0.2078 | 0.0039 | 0.045* | |
C3 | 0.8216 (13) | 0.8880 (8) | 0.4207 (9) | 0.047 (3) | |
H3A | 0.8973 | 0.8694 | 0.4907 | 0.057* | |
H3B | 0.7269 | 0.8965 | 0.4523 | 0.057* | |
H3C | 0.8487 | 0.9534 | 0.3826 | 0.057* | |
C4 | 0.6660 (13) | 0.8391 (8) | 0.1913 (8) | 0.044 (3) | |
H4A | 0.6462 | 0.7909 | 0.1199 | 0.053* | |
H4B | 0.6980 | 0.9064 | 0.1612 | 0.053* | |
H4C | 0.5762 | 0.8488 | 0.2303 | 0.053* |
U11 | U22 | U33 | U12 | U13 | U23 | |
U1 | 0.0247 (2) | 0.0179 (2) | 0.0251 (2) | 0.00006 (13) | 0.00058 (12) | 0.00017 (11) |
Cl1 | 0.0314 (12) | 0.0197 (11) | 0.0385 (11) | 0.0033 (9) | −0.0067 (8) | −0.0050 (8) |
Cl2 | 0.0366 (13) | 0.0324 (13) | 0.0412 (13) | 0.0003 (10) | −0.0095 (9) | 0.0021 (10) |
S1 | 0.0264 (12) | 0.0235 (12) | 0.0338 (11) | −0.0005 (9) | 0.0040 (8) | −0.0015 (8) |
S2 | 0.0318 (13) | 0.0245 (12) | 0.0395 (12) | 0.0020 (9) | 0.0052 (9) | 0.0044 (9) |
O1 | 0.036 (4) | 0.025 (3) | 0.032 (3) | −0.001 (3) | 0.004 (3) | −0.003 (2) |
O2 | 0.036 (4) | 0.033 (4) | 0.029 (3) | −0.003 (3) | 0.004 (2) | 0.000 (3) |
O3 | 0.032 (4) | 0.023 (3) | 0.027 (3) | 0.000 (3) | 0.000 (2) | −0.003 (2) |
O4 | 0.038 (4) | 0.014 (3) | 0.036 (3) | 0.002 (3) | 0.004 (2) | 0.002 (2) |
C1 | 0.038 (6) | 0.020 (5) | 0.051 (6) | 0.010 (4) | 0.001 (4) | −0.002 (4) |
C2 | 0.043 (6) | 0.037 (6) | 0.030 (5) | 0.008 (5) | −0.007 (4) | −0.002 (4) |
C3 | 0.051 (7) | 0.027 (6) | 0.061 (7) | −0.013 (5) | −0.001 (5) | −0.001 (5) |
C4 | 0.055 (7) | 0.041 (6) | 0.036 (5) | 0.011 (5) | 0.001 (4) | 0.018 (4) |
U1—O1 | 1.746 (7) | S2—C4 | 1.779 (9) |
U1—O2 | 1.757 (6) | S2—C3 | 1.789 (10) |
U1—O3 | 2.349 (6) | C1—H1A | 0.9800 |
U1—O4 | 2.360 (6) | C1—H1B | 0.9800 |
U1—Cl2 | 2.686 (2) | C1—H1C | 0.9800 |
U1—Cl1 | 2.844 (2) | C2—H2A | 0.9800 |
U1—Cl1i | 2.909 (2) | C2—H2B | 0.9800 |
Cl1—U1i | 2.909 (2) | C2—H2C | 0.9800 |
U1—U1i | 4.7669 (16) | C3—H3A | 0.9800 |
Cl1—Cl1i | 3.221 (3) | C3—H3B | 0.9800 |
S1—O3 | 1.535 (6) | C3—H3C | 0.9800 |
S1—C1 | 1.770 (9) | C4—H4A | 0.9800 |
S1—C2 | 1.773 (9) | C4—H4B | 0.9800 |
S2—O4 | 1.533 (6) | C4—H4C | 0.9800 |
O1—U1—O2 | 178.0 (3) | C4—S2—C3 | 100.3 (5) |
O1—U1—O3 | 86.0 (2) | S1—O3—U1 | 130.0 (4) |
O2—U1—O3 | 93.4 (2) | S2—O4—U1 | 125.9 (4) |
O1—U1—O4 | 88.6 (3) | S1—C1—H1A | 109.5 |
O2—U1—O4 | 92.8 (3) | S1—C1—H1B | 109.5 |
O3—U1—O4 | 151.3 (2) | H1A—C1—H1B | 109.5 |
O1—U1—Cl2 | 93.4 (2) | S1—C1—H1C | 109.5 |
O2—U1—Cl2 | 88.2 (2) | H1A—C1—H1C | 109.5 |
O3—U1—Cl2 | 76.21 (15) | H1B—C1—H1C | 109.5 |
O4—U1—Cl2 | 76.03 (16) | S1—C2—H2A | 109.5 |
O1—U1—Cl1 | 90.0 (2) | S1—C2—H2B | 109.5 |
O2—U1—Cl1 | 88.1 (2) | H2A—C2—H2B | 109.5 |
O3—U1—Cl1 | 71.59 (15) | S1—C2—H2C | 109.5 |
O4—U1—Cl1 | 136.62 (15) | H2A—C2—H2C | 109.5 |
Cl2—U1—Cl1 | 147.29 (7) | H2B—C2—H2C | 109.5 |
O1—U1—Cl1i | 90.8 (2) | S2—C3—H3A | 109.5 |
O2—U1—Cl1i | 88.5 (2) | S2—C3—H3B | 109.5 |
O3—U1—Cl1i | 139.54 (15) | H3A—C3—H3B | 109.5 |
O4—U1—Cl1i | 68.58 (15) | S2—C3—H3C | 109.5 |
Cl2—U1—Cl1i | 144.24 (7) | H3A—C3—H3C | 109.5 |
Cl1—U1—Cl1i | 68.09 (7) | H3B—C3—H3C | 109.5 |
U1—Cl1—U1i | 111.91 (7) | S2—C4—H4A | 109.5 |
O3—S1—C1 | 102.9 (4) | S2—C4—H4B | 109.5 |
O3—S1—C2 | 104.3 (4) | H4A—C4—H4B | 109.5 |
C1—S1—C2 | 99.2 (5) | S2—C4—H4C | 109.5 |
O4—S2—C4 | 104.1 (5) | H4A—C4—H4C | 109.5 |
O4—S2—C3 | 103.9 (4) | H4B—C4—H4C | 109.5 |
O1—U1—Cl1—U1i | −90.9 (2) | Cl2—U1—O3—S1 | 92.7 (4) |
O2—U1—Cl1—U1i | 89.2 (2) | Cl1—U1—O3—S1 | −81.5 (4) |
O3—U1—Cl1—U1i | −176.64 (17) | Cl1i—U1—O3—S1 | −86.3 (4) |
O4—U1—Cl1—U1i | −2.9 (3) | C4—S2—O4—U1 | 113.6 (5) |
Cl2—U1—Cl1—U1i | 172.88 (11) | C3—S2—O4—U1 | −141.8 (5) |
Cl1i—U1—Cl1—U1i | 0.0 | O1—U1—O4—S2 | 169.6 (5) |
C1—S1—O3—U1 | 138.5 (5) | O2—U1—O4—S2 | −9.0 (5) |
C2—S1—O3—U1 | −118.4 (5) | O3—U1—O4—S2 | −111.3 (5) |
O1—U1—O3—S1 | −172.8 (5) | Cl2—U1—O4—S2 | −96.5 (4) |
O2—U1—O3—S1 | 5.3 (5) | Cl1—U1—O4—S2 | 81.1 (4) |
O4—U1—O3—S1 | 107.4 (5) | Cl1i—U1—O4—S2 | 78.3 (4) |
Symmetry code: (i) −x+2, −y+1, −z+1. |
Experimental details
Crystal data | |
Chemical formula | [U2Cl4O4(C2H6OS)4] |
Mr | 994.37 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 173 |
a, b, c (Å) | 9.172 (3), 12.833 (4), 10.691 (2) |
β (°) | 97.72 (2) |
V (Å3) | 1247.0 (6) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 13.76 |
Crystal size (mm) | 0.33 × 0.21 × 0.15 |
Data collection | |
Diffractometer | Rigaku R-AXIS RAPID IP |
Absorption correction | Multi-scan (Higashi, 1999) |
Tmin, Tmax | 0.051, 0.128 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10244, 2849, 2330 |
Rint | 0.084 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.043, 0.111, 1.10 |
No. of reflections | 2849 |
No. of parameters | 120 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 2.54, −2.25 |
Computer programs: PROCESS-AUTO (Rigaku/MSC, 2000-2006), CrystalStructure (Rigaku/MSC, 2000-2006), SIR92 (Altomare et al. 1994), SHELXL97 (Sheldrick, 1997), ORTEPIII (Farrugia, 1997), CrystalStructure (Rigaku/MSC).
U1—O1 | 1.746 (7) | U1—Cl1 | 2.844 (2) |
U1—O2 | 1.757 (6) | U1—Cl1i | 2.909 (2) |
U1—O3 | 2.349 (6) | U1—U1i | 4.7669 (16) |
U1—O4 | 2.360 (6) | Cl1—Cl1i | 3.221 (3) |
U1—Cl2 | 2.686 (2) |
Symmetry code: (i) −x+2, −y+1, −z+1. |
Footnotes
‡This author's last name has been changed from `Mizuoka'.
References
Altomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435. CrossRef Web of Science IUCr Journals Google Scholar
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The title compound (I) was unexpectedly obtained from a hydrochloric acid aqueous solution containing U4+ and dimethyl sulfoxide (DMSO). It is reasonable to consider that I was formed by aerobic oxidation of U4+ to UO22+.
The title compound I has a dimeric structure which is bridged by two µ-Cl- between UO2Cl(DMSO)2 fragments as shown in Fig. 1. There is an inversion center in the molecular structure of I. Each U atom is seven-coordinated in a pentagonal-bipyramidal geometry. Two O atoms are at the axial positions [mean U=Oyl = 1.75 (1) Å] (Table 1). In the equatorial plane of each U, there are three Cl- ions; two of them act as µ-Cl- to bridge the U atoms in I [mean U–Clbridge = 2.88 (3) Å], and the remaining Cl- is placed at the position independent of the bridge formation [U–Clnon-bridge = 2.686 (2) Å]. The DMSO molecules in the equatorial plane coordinates to U through its O, and are non-adjacent [mean U–ODMSO = 2.35 (1) Å]. Deviations of Cl- and O of DMSO from the mean equatorial plane are within 0.15 Å. Interatomic distances between U(1)···U(1)i and µ-Cl(1)···µ-Cl(1)i [symmetry code: (i) -x + 2, -y + 1, -z + 1] are 4.7669 (3) and 3.221 (3) Å, respectively, which indicate no interatomic interaction in each pair. These structural features of I are similar to that of [UO2Cl(THF)2]2(µ-Cl)2 (THF = tetrahydrofuran) reported by Charpin et al. (1987).
Previously, some anhydrous uranyl(VI) salts, UO2Br2(THF)3, UO2Cl2(THF)3, [UO2Cl(THF)2]2(µ-Cl)2, and UO2(CF3SO3)2L3 (L = THF, pyridine), were reported (Rebizant et al. 1987, Wilkerson et al. 1999, Charpin et al. 1987, Berthet et al. 2000, respectively). In syntheses of water-sensitive uranyl(VI) compounds, e.g., alkoxides and amides, anhydrous starting materials must be used. On the other hand, THF is not very stable, and may be decomposed by its polymerization in presence of a strong acid, e.g. CF3SO3H (Calderazzo et al. 1997 and Berthet et al. 2000). Compound I also has simple composition, i.e., consisting only of UO22+, Cl-, and DMSO. The use of DMSO insead of THF expands the number of choices of the anhydrous uranyl(VI) salts as the starting material.