Poly[(μ2-2-hydr­oxy-2-methyl­propionato-κ3O1,O2:O1′)(μ2-2-hydr­oxy-2-methyl­propionato-κ2O1:κO1′)dioxido­uranium(VI)]

Yoshimura, T.; Kikunaga, H.; Shinohara, A.

doi:10.1107/S1600536809006059

metal-organic compounds

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ISSN: 2056-9890

Volume 65| Part 4| April 2009| Pages m355-m356

doi:10.1107/S1600536809006059

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Poly[(μ₂-2-hydroxy-2-methylpropionato-κ³O¹,O²:O^1′)(μ₂-2-hydroxy-2-methylpropionato-κ²O¹:κO^1′)dioxidouranium(VI)]

Takashi Yoshimura,^a ^* Hidetoshi Kikunaga ^a and Atsushi Shinohara ^a

^aDepartment of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
^*Correspondence e-mail: tyoshi@chem.sci.osaka-u.ac.jp

(Received 15 February 2009; accepted 19 February 2009; online 6 March 2009)

In the title compound, [UO₂(C₄H₇O₃)₂]_n, the dioxouranium(VI) units are linked by 2-hydroxy-2-methylpropionate ligands into a honeycomb structure. The U atom is seven-coordinate in a pentagonal-bipyramidal geometry. The uncoordinated hydroxy groups of the 2-hydroxy-2-methylpropionate ions interact with the O atom of the uranyl and with the coordinated hydroxy group of an adjacent 2-hydroxy-2-methylpropionate ion through O—H⋯O hydrogen bonds.

Related literature

For related structures, see: Back et al. (2007 ); Bombieri et al. (1973 , 1974 ); Jiang et al. (2002 ); Thuéry (2006 , 2007a ,b ,c , 2008 ); Xie et al. (2003 ); Yokoyama et al. (1990 ).

Experimental

Crystal data

[U(C₄H₇O₃)₂O₂]
M_r = 476.22
Monoclinic, P 2₁ /n
a = 9.009 (2) Å
b = 8.237 (2) Å
c = 17.552 (6) Å
β = 98.246 (9)°
V = 1289.0 (6) Å³
Z = 4
Mo Kα radiation
μ = 12.62 mm⁻¹
T = 200 K
0.20 × 0.11 × 0.03 mm

Data collection

Rigaku R-AXIS RAPID Imaging Plate diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 1995 ) T_min = 0.233, T_max = 0.685
11887 measured reflections
2949 independent reflections
2547 reflections with I > 2σ(I)
R_int = 0.050

Refinement

R[F² > 2σ(F²)] = 0.029
wR(F²) = 0.100
S = 0.86
2949 reflections
160 parameters
H-atom parameters constrained
Δρ_max = 0.99 e Å⁻³
Δρ_min = −2.15 e Å⁻³

Table 1
Selected bond lengths (Å)

U1—O1	1.783 (5)
U1—O2	1.762 (6)
U1—O3	2.444 (5)
U1—O4	2.407 (5)
U1—O5ⁱ	2.355 (4)
U1—O7	2.346 (5)
U1—O7	2.336 (5)
Symmetry code: (i) $[-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H13⋯O6	0.82	1.93	2.597 (6)	138
O6—H14⋯O1ⁱⁱ	0.82	2.00	2.777 (6)	158
Symmetry code: (ii) -x+1, -y+1, -z+1.

Data collection: PROCESS-AUTO (Rigaku, 1998 ); cell refinement: PROCESS-AUTO; data reduction: TEXSAN (Rigaku/MSC, 2004 ); program(s) used to solve structure: SIR92 (Altomare et al., 1994 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 (Farrugia, 1997 ) and Mercury (Macrae et al., 2006 ); software used to prepare material for publication: TEXSAN.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809006059/ng2546sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809006059/ng2546Isup2.hkl

checkCIF report

Comment top

Structural chemistry of uranyl(VI) complexes with hydroxycarboxylate or alkoxycarboxylate has been extensively studied (Back et al. (2007); Bombieri et al.(1973, 1974); Jiang et al. (2002); Thuéry (2006, 2007a,b,c, 2008); Xie et al. (2003); Yokoyama et al.(1990)). The crystals of the title compound (I) suitable for single-crystal X-ray analysis were obtained by the reaction of bis(acetato)dioxouranium dihydrate with an excess amount of 2-hydroxy-2-methylpropionic acid in water. Herein, we report on the crystal structure of I. Uranium(VI) atom is seven-coordinate in a pentagonal-bipyramidal structure. The two oxygen atoms are located at the axial positions with nearly linear O(1)—U(1)—O(2) angle (178.3 (2)°). The equatorial positions are coordinated by five oxygen atoms of 2-hydroxy-2-methylpropionate (HIB) ligands. Two kinds of HIB ligands exist in the asymmetric unit. One of the HIB ligands links two uranium atoms by the carboxyl group. The other chelates one uranium atom through the hydroxy and carboxyl groups, moreover the carboxyl group bridges the neighboring uranium atom. As a result, a two-dimensional honeycomb structure is formed. The IR spectrum of I shows stretching bands of the carboxyl group of HIB at 1614 and 1561 cm^-1.

Related literature top

For related structures, see: Back et al. (2007); Bombieri et al. (1973, 1974); Jiang et al. (2002); Thuéry (2006, 2007a,b,c, 2008); Xie et al. (2003); Yokoyama et al. (1990).

Experimental top

2-Hydroxy-2-methylpropionic acid (150 mg, 1.45 mmol) was added to a solution of bis(acetato)dioxouranium dihydrate (50 mg, 0.12 mmol) in 3 ml of water. The resulting yellow solution was left for several days at room temperature to give yellow crystals, which were filtered off, washed with a small amount of water, and then dried in air.

Computing details top

Data collection: PROCESS-AUTO (Rigaku, 1998); cell refinement: PROCESS-AUTO (Rigaku, 1998); data reduction: TEXSAN (Rigaku/MSC, 2004); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006); software used to prepare material for publication: TEXSAN (Rigaku/MSC, 2004).

Figures top

	Fig. 1. The assymmetric unit of I, with the atom-numbering scheme and displacement ellipsoids drawn at 50% probability level. Hydrogen atoms are omitted for clarity.
	Fig. 2. Fragment of the polymeric structure. Hydrogen atoms are omitted for clarity.
	Fig. 3. View of the polymeric structure. Hydrogen atoms are omitted for clarity.

Poly[(µ₂-2-hydroxy-2-methylpropionato- κ³O¹,O²:O^1')(µ₂-2-hydroxy-2- methylpropionato-κ²O¹:κO^1')dioxidouranium(VI)] top

Crystal data top

[U(C₄H₇O₃)₂O₂]	F(000) = 872.00
M_r = 476.22	D_x = 2.454 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.7107 Å
Hall symbol: -P 2yn	Cell parameters from 8716 reflections
a = 9.009 (2) Å	θ = 3.0–27.5°
b = 8.237 (2) Å	µ = 12.62 mm⁻¹
c = 17.552 (6) Å	T = 200 K
β = 98.246 (9)°	Platelet, yellow
V = 1289.0 (6) Å³	0.20 × 0.11 × 0.03 mm
Z = 4

Data collection top

Rigaku R-AXIS RAPID Imaging Plate diffractometer	2949 independent reflections
Radiation source: fine-focus sealed tube	2547 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.050
Detector resolution: 10.00 pixels mm^-1	θ_max = 27.5°, θ_min = 3.0°
ω scans	h = 12→11
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	k = −9→10
T_min = 0.233, T_max = 0.685	l = −22→22
11887 measured reflections

Refinement top

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)] = 0.029	H-atom parameters constrained
wR(F²) = 0.100	w = 1/[σ²(F_o²) + (0.079P)² + 5.354P] where P = (F_o² + 2F_c²)/3
S = 0.86	(Δ/σ)_max = 0.001
2949 reflections	Δρ_max = 0.99 e Å⁻³
160 parameters	Δρ_min = −2.15 e Å⁻³
Primary atom site location: structure-invariant direct methods

Crystal data top

[U(C₄H₇O₃)₂O₂]	V = 1289.0 (6) Å³
M_r = 476.22	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 9.009 (2) Å	µ = 12.62 mm⁻¹
b = 8.237 (2) Å	T = 200 K
c = 17.552 (6) Å	0.20 × 0.11 × 0.03 mm
β = 98.246 (9)°

Data collection top

Rigaku R-AXIS RAPID Imaging Plate diffractometer	2949 independent reflections
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	2547 reflections with I > 2σ(I)
T_min = 0.233, T_max = 0.685	R_int = 0.050
11887 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.029	160 parameters
wR(F²) = 0.100	H-atom parameters constrained
S = 0.86	Δρ_max = 0.99 e Å⁻³
2949 reflections	Δρ_min = −2.15 e Å⁻³

Special details top

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 > σ(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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
U(1)	0.63772 (2)	0.19668 (3)	0.62425 (1)	0.0180 (1)
O(1)	0.7538 (6)	0.3101 (5)	0.5695 (3)	0.028 (1)
O(2)	0.5188 (6)	0.0891 (6)	0.6778 (3)	0.032 (1)
O(3)	0.4753 (5)	0.4342 (5)	0.6250 (3)	0.026 (1)
O(4)	0.6920 (5)	0.3869 (6)	0.7286 (3)	0.029 (1)
O(5)	0.6435 (5)	0.6018 (6)	0.7991 (3)	0.0252 (10)
O(6)	0.2338 (5)	0.4208 (5)	0.5248 (3)	0.0241 (10)
O(7)	0.7009 (6)	−0.0415 (6)	0.5630 (3)	0.034 (1)
O(8)	0.4514 (6)	0.1975 (5)	0.5169 (3)	0.030 (1)
C(1)	0.6115 (7)	0.5015 (8)	0.7435 (3)	0.022 (1)
C(2)	0.4611 (7)	0.5295 (8)	0.6929 (4)	0.021 (1)
C(3)	0.3351 (8)	0.463 (1)	0.7324 (4)	0.036 (2)
C(4)	0.4392 (10)	0.7064 (7)	0.6704 (5)	0.030 (2)
C(5)	0.3241 (7)	0.1601 (8)	0.4820 (4)	0.020 (1)
C(6)	0.1889 (7)	0.2626 (8)	0.4949 (4)	0.021 (1)
C(7)	0.1191 (10)	0.1790 (9)	0.5588 (5)	0.039 (2)
C(8)	0.0781 (10)	0.280 (1)	0.4211 (5)	0.038 (2)
H(1)	0.3277	0.5253	0.7779	0.0356*
H(2)	0.2423	0.4698	0.6980	0.0356*
H(3)	0.3555	0.3516	0.7462	0.0356*
H(4)	0.4388	0.7711	0.7159	0.0297*
H(5)	0.3454	0.7192	0.6374	0.0297*
H(6)	0.5196	0.7409	0.6438	0.0297*
H(7)	0.0321	0.2384	0.5684	0.0386*
H(8)	0.1908	0.1757	0.6048	0.0386*
H(9)	0.0907	0.0703	0.5432	0.0386*
H(10)	−0.0100	0.3359	0.4322	0.0383*
H(11)	0.0507	0.1746	0.4007	0.0383*
H(12)	0.1237	0.3413	0.3841	0.0383*
H(13)	0.4210	0.4724	0.5878	0.0255*
H(14)	0.2178	0.4883	0.4902	0.0241*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
U(1)	0.0192 (2)	0.0158 (2)	0.0185 (2)	0.00083 (8)	0.0005 (1)	−0.00114 (8)
O(1)	0.022 (3)	0.030 (3)	0.032 (3)	0.007 (2)	0.004 (2)	0.007 (2)
O(2)	0.029 (3)	0.025 (2)	0.044 (3)	0.005 (2)	0.009 (2)	0.007 (2)
O(3)	0.034 (3)	0.022 (2)	0.017 (2)	0.008 (2)	−0.008 (2)	−0.005 (2)
O(4)	0.029 (3)	0.025 (2)	0.030 (2)	0.007 (2)	−0.004 (2)	−0.006 (2)
O(5)	0.028 (2)	0.027 (2)	0.020 (2)	−0.008 (2)	0.001 (2)	−0.010 (2)
O(6)	0.030 (2)	0.016 (2)	0.023 (2)	0.002 (2)	−0.005 (2)	−0.001 (2)
O(7)	0.032 (3)	0.027 (3)	0.038 (3)	0.009 (2)	−0.008 (2)	−0.018 (2)
O(8)	0.023 (3)	0.033 (3)	0.033 (3)	0.005 (2)	−0.002 (2)	−0.008 (2)
C(1)	0.023 (3)	0.024 (3)	0.017 (3)	−0.007 (3)	0.000 (2)	−0.001 (3)
C(2)	0.027 (3)	0.016 (3)	0.020 (3)	0.000 (3)	0.000 (2)	−0.008 (2)
C(3)	0.032 (4)	0.042 (4)	0.035 (4)	−0.012 (3)	0.009 (3)	−0.013 (3)
C(4)	0.040 (4)	0.015 (3)	0.032 (4)	0.004 (3)	−0.001 (3)	−0.004 (3)
C(5)	0.022 (3)	0.019 (3)	0.020 (3)	0.009 (3)	0.001 (2)	0.002 (3)
C(6)	0.021 (3)	0.018 (3)	0.022 (3)	0.013 (3)	−0.003 (2)	0.003 (3)
C(7)	0.035 (4)	0.036 (4)	0.048 (5)	−0.015 (3)	0.017 (4)	−0.005 (3)
C(8)	0.035 (4)	0.035 (4)	0.040 (4)	0.014 (3)	−0.012 (4)	−0.004 (4)

Geometric parameters (Å, º) top

U(1)—O(1)	1.783 (5)	C(2)—C(4)	1.514 (9)
U(1)—O(2)	1.762 (6)	C(3)—H(1)	0.960
U(1)—O(3)	2.444 (5)	C(3)—H(2)	0.960
U(1)—O(4)	2.407 (5)	C(3)—H(3)	0.960
U(1)—O(5)ⁱ	2.355 (4)	C(4)—H(4)	0.960
U(1)—O(7)	2.346 (5)	C(4)—H(5)	0.960
U(1)—O(8)	2.336 (5)	C(4)—H(6)	0.960
O(3)—C(2)	1.449 (8)	C(5)—C(6)	1.525 (10)
O(3)—H(13)	0.820	C(6)—C(7)	1.53 (1)
O(4)—C(1)	1.241 (8)	C(6)—C(8)	1.523 (10)
O(5)—C(1)	1.280 (8)	C(7)—H(7)	0.960
O(6)—C(6)	1.441 (8)	C(7)—H(8)	0.960
O(6)—H(14)	0.820	C(7)—H(9)	0.960
O(7)—C(5)ⁱⁱ	1.257 (8)	C(8)—H(10)	0.960
O(8)—C(5)	1.259 (8)	C(8)—H(11)	0.960
C(1)—C(2)	1.528 (8)	C(8)—H(12)	0.960
C(2)—C(3)	1.51 (1)

O(1)—U(1)—O(2)	178.3 (2)	C(1)—C(2)—C(4)	111.6 (6)
O(1)—U(1)—O(3)	88.9 (2)	C(3)—C(2)—C(4)	112.9 (6)
O(1)—U(1)—O(4)	89.9 (2)	C(2)—C(3)—H(1)	109.5
O(1)—U(1)—O(5)ⁱ	88.5 (2)	C(2)—C(3)—H(2)	109.5
O(1)—U(1)—O(7)	89.5 (2)	C(2)—C(3)—H(3)	109.5
O(1)—U(1)—O(8)	88.5 (2)	H(1)—C(3)—H(2)	109.5
O(2)—U(1)—O(3)	89.4 (2)	H(1)—C(3)—H(3)	109.5
O(2)—U(1)—O(4)	89.7 (2)	H(2)—C(3)—H(3)	109.5
O(2)—U(1)—O(5)ⁱ	93.0 (2)	C(2)—C(4)—H(4)	109.5
O(2)—U(1)—O(7)	91.7 (2)	C(2)—C(4)—H(5)	109.5
O(2)—U(1)—O(8)	90.6 (2)	C(2)—C(4)—H(6)	109.5
O(3)—U(1)—O(4)	62.1 (1)	H(4)—C(4)—H(5)	109.5
O(3)—U(1)—O(5)ⁱ	135.7 (2)	H(4)—C(4)—H(6)	109.5
O(3)—U(1)—O(7)	148.9 (2)	H(5)—C(4)—H(6)	109.5
O(3)—U(1)—O(8)	68.9 (2)	O(7)ⁱⁱ—C(5)—O(8)	124.4 (6)
O(4)—U(1)—O(5)ⁱ	73.7 (2)	O(7)ⁱⁱ—C(5)—C(6)	116.7 (6)
O(4)—U(1)—O(7)	149.0 (2)	O(8)—C(5)—C(6)	119.0 (6)
O(4)—U(1)—O(8)	131.0 (2)	O(6)—C(6)—C(5)	111.4 (5)
O(5)ⁱ—U(1)—O(7)	75.3 (2)	O(6)—C(6)—C(7)	105.3 (5)
O(5)ⁱ—U(1)—O(8)	155.1 (2)	O(6)—C(6)—C(8)	109.8 (6)
O(7)—U(1)—O(8)	80.0 (2)	C(5)—C(6)—C(7)	106.3 (6)
U(1)—O(3)—C(2)	124.2 (3)	C(5)—C(6)—C(8)	111.5 (6)
U(1)—O(3)—H(13)	126.3	C(7)—C(6)—C(8)	112.2 (6)
C(2)—O(3)—H(13)	109.5	C(6)—C(7)—H(7)	109.5
U(1)—O(4)—C(1)	126.5 (4)	C(6)—C(7)—H(8)	109.5
U(1)ⁱⁱⁱ—O(5)—C(1)	136.7 (4)	C(6)—C(7)—H(9)	109.5
C(6)—O(6)—H(14)	109.5	H(7)—C(7)—H(8)	109.5
U(1)—O(7)—C(5)ⁱⁱ	154.9 (4)	H(7)—C(7)—H(9)	109.5
U(1)—O(8)—C(5)	153.0 (5)	H(8)—C(7)—H(9)	109.5
O(4)—C(1)—O(5)	125.3 (6)	C(6)—C(8)—H(10)	109.5
O(4)—C(1)—C(2)	119.3 (5)	C(6)—C(8)—H(11)	109.5
O(5)—C(1)—C(2)	115.4 (6)	C(6)—C(8)—H(12)	109.5
O(3)—C(2)—C(1)	102.7 (5)	H(10)—C(8)—H(11)	109.5
O(3)—C(2)—C(3)	109.9 (5)	H(10)—C(8)—H(12)	109.5
O(3)—C(2)—C(4)	109.3 (5)	H(11)—C(8)—H(12)	109.5
C(1)—C(2)—C(3)	109.9 (5)

Symmetry codes: (i) −x+3/2, y−1/2, −z+3/2; (ii) −x+1, −y, −z+1; (iii) −x+3/2, y+1/2, −z+3/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O(3)—H(13)···O(6)	0.820	1.927	2.597 (6)	138.188
O(6)—H(14)···O(1)^iv	0.820	1.999	2.777 (6)	158.201

Symmetry code: (iv) −x+1, −y+1, −z+1.

Experimental details

Crystal data
Chemical formula	[U(C₄H₇O₃)₂O₂]
M_r	476.22
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	200
a, b, c (Å)	9.009 (2), 8.237 (2), 17.552 (6)
β (°)	98.246 (9)
V (Å³)	1289.0 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	12.62
Crystal size (mm)	0.20 × 0.11 × 0.03

Data collection
Diffractometer	Rigaku R-AXIS RAPID Imaging Plate diffractometer
Absorption correction	Multi-scan (ABSCOR; Higashi, 1995)
T_min, T_max	0.233, 0.685
No. of measured, independent and observed [I > 2σ(I)] reflections	11887, 2949, 2547
R_int	0.050
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.029, 0.100, 0.86
No. of reflections	2949
No. of parameters	160
No. of restraints	?
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.99, −2.15

Computer programs: PROCESS-AUTO (Rigaku, 1998), TEXSAN (Rigaku/MSC, 2004), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006).

Selected bond lengths (Å) top

U(1)—O(1)	1.783 (5)	U(1)—O(5)ⁱ	2.355 (4)
U(1)—O(2)	1.762 (6)	U(1)—O(7)	2.346 (5)
U(1)—O(3)	2.444 (5)	U(1)—O(8)	2.336 (5)
U(1)—O(4)	2.407 (5)

Symmetry code: (i) −x+3/2, y−1/2, −z+3/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O(3)—H(13)···O(6)	0.820	1.927	2.597 (6)	138.188
O(6)—H(14)···O(1)ⁱⁱ	0.820	1.999	2.777 (6)	158.201

Symmetry code: (ii) −x+1, −y+1, −z+1.

Acknowledgements

The present study is the result of the efficient separation and analysis of nuclear fission products for reprocessing systems entrusted to Osaka University by the Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT).

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