μ-η:η-Peroxido-bis-[nitratodioxido-bis(pyrrolidin-2-one)uranium(VI)].

In the crystal structure of the title compound, [U(2)(NO(3))(2)O(4)(O(2))(C(4)H(7)NO)(4)], two UO(2) (2+) ions are connected by a μ-η(2):η(2)-O(2) unit. The O(2) unit shows 'side-on' coordination to both U atoms. An inversion center is located at the midpoint of the O-O bond in the O(2) unit, affording a centrosymmetrically expanded dimeric structure. The U-O(axial) bond lengths are 1.777 (4) Å and 1.784 (4) Å, indicating that the oxidation state of U is exclusively 6+, i.e., UO(2) (2+). Furthermore, the O-O distance is 1.492 (8) Å, which is typical of peroxide, O(2) (2-). The U atom is eight-coordinated in a hexa-gonal-bipyramidal geometry. The coordinating atoms of the nitrate and pyrrolidine-2-one ligands and the μ-η(2):η(2)-O(2) (2-) unit are located in the equatorial plane and form an irregular hexa-gon. An inter-molecular hydrogen bond is found between N-H of the pyrrolidine-2-one ligand and the coordinating O of the same ligand in a neighboring complex. A second inter-molecular hydrogen bond is found between the N-H of the other pyrrolidine-2-one ligand and one of the uranyl oxido atoms.

Related literature

For the structural chemistry of uran­yl(VI)–peroxido complexes, see: Haegele & Boeyens (1977 ▶); Charpin et al. (1985 ▶); Doyle et al. (1993 ▶); Rose et al. (1994 ▶); Thuéry et al. (1999 ▶); de Aquino et al. (2001 ▶); John et al. (2004 ▶); Masci & Thuéry (2005 ▶); Zehnder et al. (2005 ▶); Kubatko et al. (2007 ▶); Ikeda et al. (2007 ▶); Takao et al. (2009 ▶); Vaska (1976 ▶).

Experimental

Crystal data

[U2(NO3)2O4(O2)(C4H7NO)4]

M = 1036.50

Triclinic,

a = 8.783 (2) Å

b = 8.899 (3) Å

c = 9.587 (3) Å

α = 68.24 (3)°

β = 81.30 (2)°

γ = 68.96 (2)°

V = 649.4 (3) Å3

Z = 1

Mo Kα radiation

μ = 12.54 mm−1

T = 173 K

0.30 × 0.20 × 0.20 mm

Data collection

Rigaku R-AXIS RAPID diffractometer

Absorption correction: numerical (NUMABS; Higashi, 1999 ▶) T min = 0.117, T max = 0.188

5524 measured reflections

2934 independent reflections

2727 reflections with I > 2σ(I)

R int = 0.037

Refinement

R[F 2 > 2σ(F 2)] = 0.026

wR(F 2) = 0.064

S = 1.00

2934 reflections

181 parameters

H-atom parameters constrained

Δρmax = 2.04 e Å−3

Δρmin = −0.97 e Å−3

Data collection: PROCESS-AUTO (Rigaku/MSC, 2006 ▶); cell refinement: PROCESS-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 2006 ▶); program(s) used to solve structure: DIRDIF99 (Beurskens et al., 1999 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 (Farrugia, 1997 ▶); software used to prepare material for publication: CrystalStructure.

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810013449/om2328sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810013449/om2328Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

[U2(NO3)2O4(O2)(C4H7NO)4]	Z = 1
Mr = 1036.50	F(000) = 478
Triclinic, P1	Dx = 2.650 Mg m−3
a = 8.783 (2) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.899 (3) Å	Cell parameters from 6275 reflections
c = 9.587 (3) Å	θ = 3.1–27.5°
α = 68.24 (3)°	µ = 12.54 mm−1
β = 81.30 (2)°	T = 173 K
γ = 68.96 (2)°	Platelet, orange
V = 649.4 (3) Å3	0.30 × 0.20 × 0.20 mm

Rigaku R-AXIS RAPID diffractometer	2934 independent reflections
Radiation source: fine-focus sealed tube	2727 reflections with I > 2σ(I)
graphite	Rint = 0.037
Detector resolution: 10.00 pixels mm-1	θmax = 27.5°, θmin = 3.1°
ω scans	h = −11→11
Absorption correction: numerical (NUMABS; Higashi, 1999)	k = −11→11
Tmin = 0.117, Tmax = 0.188	l = −12→12
5524 measured reflections

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.026	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.064	H-atom parameters constrained
S = 1.00	w = 1/[σ2(Fo2) + (0.0387P)2 + 2.5299P] where P = (Fo2 + 2Fc2)/3
2934 reflections	(Δ/σ)max < 0.001
181 parameters	Δρmax = 2.04 e Å−3
0 restraints	Δρmin = −0.97 e Å−3

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

	x	y	z	Uiso*/Ueq
U1	0.21945 (2)	0.38333 (2)	0.134424 (19)	0.01484 (7)
O1	0.1573 (5)	0.2025 (6)	0.2384 (5)	0.0283 (9)
O2	0.2956 (6)	0.5569 (5)	0.0387 (5)	0.0290 (9)
O3	−0.0454 (5)	0.5419 (7)	0.0555 (5)	0.0427 (13)
O4	0.0681 (4)	0.5317 (5)	0.3068 (4)	0.0184 (7)
O5	0.3773 (5)	0.2945 (5)	0.3554 (4)	0.0233 (8)
O6	0.5044 (5)	0.1836 (5)	0.1196 (4)	0.0253 (8)
O7	0.3597 (5)	0.2765 (6)	−0.0771 (5)	0.0274 (9)
O8	0.6150 (5)	0.1159 (6)	−0.0778 (5)	0.0320 (10)
N1	−0.1016 (6)	0.7323 (6)	0.4011 (5)	0.0219 (9)
H1	−0.1109	0.6587	0.4908	0.026*
N2	0.6174 (6)	0.3525 (6)	0.3046 (6)	0.0252 (10)
H2	0.6093	0.3951	0.2062	0.030*
N3	0.4985 (6)	0.1888 (6)	−0.0142 (5)	0.0220 (9)
C1	−0.0129 (6)	0.6859 (6)	0.2925 (6)	0.0162 (9)
C2	−0.0222 (7)	0.8410 (7)	0.1547 (6)	0.0232 (11)
H2A	−0.0899	0.8478	0.0774	0.028*
H2B	0.0879	0.8390	0.1114	0.028*
C3	−0.1017 (7)	0.9916 (7)	0.2126 (6)	0.0220 (11)
H3A	−0.0184	1.0345	0.2284	0.026*
H3B	−0.1825	1.0869	0.1408	0.026*
C4	−0.1845 (8)	0.9175 (7)	0.3610 (7)	0.0289 (13)
H4A	−0.1688	0.9593	0.4384	0.035*
H4B	−0.3028	0.9477	0.3484	0.035*
C5	0.5058 (6)	0.2954 (7)	0.3950 (6)	0.0183 (10)
C6	0.5538 (7)	0.2302 (9)	0.5552 (7)	0.0285 (12)
H6A	0.5754	0.1051	0.6004	0.034*
H6B	0.4671	0.2882	0.6150	0.034*
C7	0.7558 (8)	0.3392 (9)	0.3818 (8)	0.0336 (14)
H7A	0.7700	0.4524	0.3536	0.040*
H7B	0.8580	0.2579	0.3574	0.040*
C8	0.7105 (8)	0.2736 (9)	0.5478 (7)	0.0314 (13)
H8A	0.6906	0.3626	0.5933	0.038*
H8B	0.7993	0.1703	0.6025	0.038*

	U11	U22	U33	U12	U13	U23
U1	0.01539 (10)	0.01631 (10)	0.01212 (10)	−0.00364 (7)	−0.00246 (6)	−0.00480 (7)
O1	0.026 (2)	0.029 (2)	0.036 (2)	−0.0151 (17)	0.0063 (17)	−0.0150 (19)
O2	0.039 (2)	0.024 (2)	0.023 (2)	−0.0135 (18)	0.0088 (17)	−0.0083 (17)
O3	0.030 (2)	0.058 (3)	0.033 (2)	0.019 (2)	−0.0158 (19)	−0.035 (3)
O4	0.0237 (18)	0.0151 (17)	0.0135 (16)	−0.0020 (14)	−0.0020 (14)	−0.0053 (14)
O5	0.0199 (18)	0.034 (2)	0.0158 (18)	−0.0079 (16)	−0.0062 (14)	−0.0077 (16)
O6	0.0233 (19)	0.030 (2)	0.0205 (19)	−0.0036 (16)	−0.0038 (15)	−0.0099 (17)
O7	0.026 (2)	0.030 (2)	0.0210 (19)	0.0021 (16)	−0.0052 (16)	−0.0117 (17)
O8	0.024 (2)	0.034 (2)	0.034 (2)	−0.0005 (17)	0.0046 (17)	−0.019 (2)
N1	0.031 (2)	0.012 (2)	0.018 (2)	−0.0049 (17)	0.0034 (18)	−0.0043 (17)
N2	0.028 (2)	0.027 (2)	0.020 (2)	−0.011 (2)	−0.0015 (19)	−0.006 (2)
N3	0.024 (2)	0.022 (2)	0.021 (2)	−0.0057 (18)	−0.0002 (18)	−0.0099 (19)
C1	0.019 (2)	0.016 (2)	0.015 (2)	−0.0066 (18)	−0.0017 (18)	−0.0056 (19)
C2	0.035 (3)	0.017 (2)	0.015 (2)	−0.009 (2)	0.001 (2)	−0.002 (2)
C3	0.022 (2)	0.019 (3)	0.021 (3)	−0.006 (2)	−0.001 (2)	−0.002 (2)
C4	0.036 (3)	0.017 (3)	0.025 (3)	−0.002 (2)	0.007 (2)	−0.006 (2)
C5	0.021 (2)	0.015 (2)	0.015 (2)	−0.0003 (18)	−0.0060 (19)	−0.0050 (19)
C6	0.027 (3)	0.043 (4)	0.020 (3)	−0.015 (3)	−0.005 (2)	−0.011 (3)
C7	0.027 (3)	0.039 (4)	0.042 (4)	−0.016 (3)	0.001 (3)	−0.018 (3)
C8	0.029 (3)	0.041 (4)	0.030 (3)	−0.013 (3)	−0.007 (2)	−0.015 (3)

U1—O1	1.777 (4)	N2—C7	1.464 (8)
U1—O2	1.784 (4)	N2—H2	0.8800
U1—O3i	2.303 (4)	C1—C2	1.503 (7)
U1—O3	2.315 (4)	C2—C3	1.534 (8)
U1—O5	2.428 (4)	C2—H2A	0.9900
U1—O4	2.436 (4)	C2—H2B	0.9900
U1—O6	2.515 (4)	C3—C4	1.524 (8)
U1—O7	2.523 (4)	C3—H3A	0.9900
U1—N3	2.960 (5)	C3—H3B	0.9900
O3—O3i	1.492 (8)	C4—H4A	0.9900
O3—U1i	2.303 (4)	C4—H4B	0.9900
O4—C1	1.264 (6)	C5—C6	1.494 (7)
O5—C5	1.247 (6)	C6—C8	1.543 (8)
O6—N3	1.275 (6)	C6—H6A	0.9900
O7—N3	1.284 (6)	C6—H6B	0.9900
O8—N3	1.211 (6)	C7—C8	1.523 (9)
N1—C1	1.305 (7)	C7—H7A	0.9900
N1—C4	1.465 (7)	C7—H7B	0.9900
N1—H1	0.8800	C8—H8A	0.9900
N2—C5	1.321 (7)	C8—H8B	0.9900
O1—U1—O2	175.6 (2)	O8—N3—O6	122.6 (5)
O1—U1—O3i	90.6 (2)	O8—N3—O7	122.2 (5)
O2—U1—O3i	93.5 (2)	O6—N3—O7	115.2 (4)
O1—U1—O3	90.0 (2)	O8—N3—U1	176.9 (4)
O2—U1—O3	94.2 (2)	O6—N3—U1	57.5 (2)
O3i—U1—O3	37.70 (19)	O7—N3—U1	57.9 (2)
O1—U1—O5	83.92 (18)	O4—C1—N1	123.2 (5)
O2—U1—O5	92.05 (18)	O4—C1—C2	126.9 (5)
O3i—U1—O5	173.10 (16)	N1—C1—C2	109.9 (4)
O3—U1—O5	137.69 (14)	C1—C2—C3	103.7 (4)
O1—U1—O4	91.03 (16)	C1—C2—H2A	111.0
O2—U1—O4	89.17 (16)	C3—C2—H2A	111.0
O3i—U1—O4	106.98 (13)	C1—C2—H2B	111.0
O3—U1—O4	69.31 (13)	C3—C2—H2B	111.0
O5—U1—O4	68.98 (13)	H2A—C2—H2B	109.0
O1—U1—O6	89.08 (17)	C4—C3—C2	104.6 (4)
O2—U1—O6	87.70 (18)	C4—C3—H3A	110.8
O3i—U1—O6	117.42 (13)	C2—C3—H3A	110.8
O3—U1—O6	155.09 (14)	C4—C3—H3B	110.8
O5—U1—O6	66.88 (13)	C2—C3—H3B	110.8
O4—U1—O6	135.59 (13)	H3A—C3—H3B	108.9
O1—U1—O7	96.11 (18)	N1—C4—C3	103.3 (4)
O2—U1—O7	84.17 (17)	N1—C4—H4A	111.1
O3i—U1—O7	67.09 (14)	C3—C4—H4A	111.1
O3—U1—O7	104.63 (14)	N1—C4—H4B	111.1
O5—U1—O7	117.64 (13)	C3—C4—H4B	111.1
O4—U1—O7	170.69 (12)	H4A—C4—H4B	109.1
O6—U1—O7	50.79 (13)	O5—C5—N2	125.9 (5)
O1—U1—N3	93.83 (17)	O5—C5—C6	123.6 (5)
O2—U1—N3	84.52 (17)	N2—C5—C6	110.5 (5)
O3i—U1—N3	92.51 (14)	C5—C6—C8	104.3 (5)
O3—U1—N3	130.14 (14)	C5—C6—H6A	110.9
O5—U1—N3	92.10 (13)	C8—C6—H6A	110.9
O4—U1—N3	159.86 (13)	C5—C6—H6B	110.9
O6—U1—N3	25.29 (13)	C8—C6—H6B	110.9
O7—U1—N3	25.54 (13)	H6A—C6—H6B	108.9
O3i—O3—U1i	71.6 (3)	N2—C7—C8	104.1 (5)
O3i—O3—U1	70.7 (3)	N2—C7—H7A	110.9
U1i—O3—U1	142.30 (19)	C8—C7—H7A	110.9
C1—O4—U1	134.6 (3)	N2—C7—H7B	110.9
C5—O5—U1	141.9 (4)	C8—C7—H7B	110.9
N3—O6—U1	97.2 (3)	H7A—C7—H7B	109.0
N3—O7—U1	96.6 (3)	C7—C8—C6	106.1 (5)
C1—N1—C4	114.3 (5)	C7—C8—H8A	110.5
C1—N1—H1	122.9	C6—C8—H8A	110.5
C4—N1—H1	122.9	C7—C8—H8B	110.5
C5—N2—C7	114.4 (5)	C6—C8—H8B	110.5
C5—N2—H2	122.8	H8A—C8—H8B	108.7
C7—N2—H2	122.8
O1—U1—O3—O3i	−91.0 (5)	U1—O6—N3—O8	176.3 (5)
O2—U1—O3—O3i	90.3 (5)	U1—O6—N3—O7	−3.9 (5)
O5—U1—O3—O3i	−172.0 (3)	U1—O7—N3—O8	−176.3 (5)
O4—U1—O3—O3i	177.9 (5)	U1—O7—N3—O6	3.9 (5)
O6—U1—O3—O3i	−3.2 (8)	O1—U1—N3—O8	−173 (7)
O7—U1—O3—O3i	5.3 (5)	O2—U1—N3—O8	3(7)
N3—U1—O3—O3i	4.0 (6)	O3i—U1—N3—O8	96 (7)
O1—U1—O3—U1i	−91.0 (5)	O3—U1—N3—O8	94 (7)
O2—U1—O3—U1i	90.3 (5)	O5—U1—N3—O8	−89 (7)
O3i—U1—O3—U1i	0.000 (2)	O4—U1—N3—O8	−69 (7)
O5—U1—O3—U1i	−172.0 (3)	O6—U1—N3—O8	−93 (7)
O4—U1—O3—U1i	177.9 (5)	O7—U1—N3—O8	91 (7)
O6—U1—O3—U1i	−3.2 (8)	O1—U1—N3—O6	−79.7 (3)
O7—U1—O3—U1i	5.3 (5)	O2—U1—N3—O6	96.2 (3)
N3—U1—O3—U1i	4.0 (6)	O3i—U1—N3—O6	−170.5 (3)
O1—U1—O4—C1	−144.0 (5)	O3—U1—N3—O6	−172.9 (3)
O2—U1—O4—C1	40.4 (5)	O5—U1—N3—O6	4.4 (3)
O3i—U1—O4—C1	−53.0 (5)	O4—U1—N3—O6	23.9 (6)
O3—U1—O4—C1	−54.3 (5)	O7—U1—N3—O6	−175.8 (5)
O5—U1—O4—C1	132.9 (5)	O1—U1—N3—O7	96.2 (3)
O6—U1—O4—C1	126.3 (4)	O2—U1—N3—O7	−87.9 (3)
O7—U1—O4—C1	−3.8 (11)	O3i—U1—N3—O7	5.3 (4)
N3—U1—O4—C1	111.9 (5)	O3—U1—N3—O7	2.9 (4)
O1—U1—O5—C5	149.6 (6)	O5—U1—N3—O7	−179.8 (3)
O2—U1—O5—C5	−28.6 (6)	O4—U1—N3—O7	−160.2 (3)
O3i—U1—O5—C5	−172.1 (11)	O6—U1—N3—O7	175.8 (5)
O3—U1—O5—C5	−127.0 (6)	U1—O4—C1—N1	171.1 (4)
O4—U1—O5—C5	−116.9 (6)	U1—O4—C1—C2	−9.6 (8)
O6—U1—O5—C5	58.0 (6)	C4—N1—C1—O4	179.5 (5)
O7—U1—O5—C5	55.9 (6)	C4—N1—C1—C2	0.2 (7)
N3—U1—O5—C5	56.0 (6)	O4—C1—C2—C3	−166.8 (5)
O1—U1—O6—N3	101.0 (3)	N1—C1—C2—C3	12.5 (6)
O2—U1—O6—N3	−82.0 (3)	C1—C2—C3—C4	−19.4 (6)
O3i—U1—O6—N3	10.7 (4)	C1—N1—C4—C3	−12.8 (7)
O3—U1—O6—N3	12.9 (6)	C2—C3—C4—N1	19.4 (6)
O5—U1—O6—N3	−175.2 (3)	U1—O5—C5—N2	−3.6 (9)
O4—U1—O6—N3	−168.5 (3)	U1—O5—C5—C6	176.3 (4)
O7—U1—O6—N3	2.3 (3)	C7—N2—C5—O5	179.5 (5)
O1—U1—O7—N3	−86.1 (3)	C7—N2—C5—C6	−0.4 (7)
O2—U1—O7—N3	89.5 (3)	O5—C5—C6—C8	−174.8 (5)
O3i—U1—O7—N3	−174.2 (4)	N2—C5—C6—C8	5.1 (7)
O3—U1—O7—N3	−177.7 (3)	C5—N2—C7—C8	−4.6 (7)
O5—U1—O7—N3	0.2 (4)	N2—C7—C8—C6	7.3 (7)
O4—U1—O7—N3	134.0 (7)	C5—C6—C8—C7	−7.6 (7)
O6—U1—O7—N3	−2.3 (3)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O4ii	0.88	2.03	2.885 (6)	165
N2—H2···O2iii	0.88	2.31	3.127 (7)	156

U1—O1	1.777 (4)
U1—O2	1.784 (4)
U1—O3i	2.303 (4)
U1—O3	2.315 (4)
U1—O5	2.428 (4)
U1—O4	2.436 (4)
U1—O6	2.515 (4)
U1—O7	2.523 (4)
O3—O3i	1.492 (8)

O1—U1—O2	175.6 (2)
O3i—U1—O3	37.70 (19)

Symmetry code: (i) .

Table 2

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O4ii	0.88	2.03	2.885 (6)	165
N2—H2⋯O2iii	0.88	2.31	3.127 (7)	156

Symmetry codes: (ii) ; (iii) .