Pyridinium trans-di-aqua-bis-[oxalato(2-)-κ(2) O (1),O (2)]chromate(III) urea monosolvate.

The asymmetric unit of the title solvated mol-ecular salt, (C5H6N)[Cr(C2O4)2(H2O)2]·CO(NH2)2, contains half a formula unit. Each component is completed by crystallographic twofold symmetry: in the cation, one C and the N atom lie on the rotation axis; in the anion, the Cr(III) ion lies on the axis; in the solvent mol-ecule, the C and the O atom lie on the axis. The aqua ligands are in a trans disposition in the resulting CrO6 octa-hedron. In the crystal, the components are linked by O-H⋯O, N-H⋯O and N-H⋯(O,O) hydrogen bonds, generating a three-dimensional network.

Related literature

For mol­ecular salts containing the [Cr(C2O4)2(H2O)2]− anion, see: Bélombé et al. (2009 ▶); Nenwa et al. (2010 ▶, 2012 ▶); Chérif et al. (2011 ▶); Chérif, Zid et al. (2012 ▶); Chérif, Abdelhak et al. (2012 ▶); Dridi et al. (2013 ▶).

Experimental

Crystal data

(C5H6N)[Cr(C2O4)2(H2O)2]·CH4N2O

M = 404.24

Monoclinic,

a = 7.6456 (7) Å

b = 21.4096 (18) Å

c = 9.7404 (12) Å

β = 100.278 (1)°

V = 1568.8 (3) Å3

Z = 4

Mo Kα radiation

μ = 0.80 mm−1

T = 293 K

0.20 × 0.16 × 0.13 mm

Data collection

Bruker APEX CCD diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2004 ▶) T min = 0.851, T max = 0.935

11770 measured reflections

2343 independent reflections

1980 reflections with I > 2σ(I)

R int = 0.032

Refinement

R[F 2 > 2σ(F 2)] = 0.041

wR(F 2) = 0.111

S = 1.10

2343 reflections

132 parameters

5 restraints

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.30 e Å−3

Δρmin = −0.56 e Å−3

Data collection: SMART (Bruker, 2004 ▶); cell refinement: SAINT (Bruker, 2004 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: DIAMOND (Brandenburg, 2010 ▶); software used to prepare material for publication: WinGX (Farrugia, 2012 ▶).

Crystal structure: contains datablock(s) I. DOI: 10.1107/S1600536813026135/hb7141sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536813026135/hb7141Isup2.hkl

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

(C5H6N)[Cr(C2O4)2(H2O)2]·CH4N2O	Z = 4
Mr = 404.24	F(000) = 828
Monoclinic, I2/a	Dx = 1.712 Mg m−3
Hall symbol: -I 2ya	Mo Kα radiation, λ = 0.71073 Å
a = 7.6456 (7) Å	µ = 0.80 mm−1
b = 21.4096 (18) Å	T = 293 K
c = 9.7404 (12) Å	Prism, violet
β = 100.278 (1)°	0.20 × 0.16 × 0.13 mm
V = 1568.8 (3) Å3

Bruker APEX CCD diffractometer	2343 independent reflections
Radiation source: fine-focus sealed tube	1980 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.032
ω scans	θmax = 30.9°, θmin = 2.3°
Absorption correction: multi-scan (SADABS; Bruker, 2004)	h = −10→10
Tmin = 0.851, Tmax = 0.935	k = −30→30
11770 measured reflections	l = −13→14

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)] = 0.041	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.111	H atoms treated by a mixture of independent and constrained refinement
S = 1.10	w = 1/[σ2(Fo2) + (0.0515P)2 + 1.3542P] where P = (Fo2 + 2Fc2)/3
2343 reflections	(Δ/σ)max < 0.001
132 parameters	Δρmax = 0.30 e Å−3
5 restraints	Δρmin = −0.56 e Å−3

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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
Cr4	0.2500	0.223340 (17)	0.0000	0.02410 (13)
O1	0.45417 (19)	0.22672 (6)	−0.10198 (14)	0.0315 (3)
O2	0.35892 (18)	0.15558 (6)	0.11799 (13)	0.0324 (3)
O3	0.14209 (17)	0.29281 (6)	−0.11952 (12)	0.0288 (3)
O4	0.1309 (2)	0.39675 (7)	−0.12681 (15)	0.0436 (4)
O5	0.3604 (2)	0.05182 (7)	0.13176 (16)	0.0498 (4)
C1	0.1842 (2)	0.34777 (8)	−0.07105 (17)	0.0285 (3)
C2	0.3134 (3)	0.10049 (8)	0.07197 (18)	0.0319 (4)
N1	0.7500	0.48039 (15)	0.0000	0.0622 (8)
H1	0.7500	0.5206	0.0000	0.075*
C3	0.8444 (3)	0.38759 (15)	0.1108 (3)	0.0576 (7)
H3	0.9099	0.3668	0.1868	0.069*
C4	0.7500	0.35421 (17)	0.0000	0.0527 (8)
H4	0.7500	0.3108	0.0000	0.063*
C5	0.8402 (4)	0.45021 (15)	0.1071 (3)	0.0594 (7)
H5	0.9023	0.4727	0.1819	0.071*
O6	0.7500	0.17120 (9)	0.0000	0.0388 (4)
N2	0.6418 (3)	0.08022 (9)	−0.0971 (2)	0.0447 (4)
C6	0.7500	0.11234 (13)	0.0000	0.0326 (5)
H2A	0.584 (3)	0.0960 (12)	−0.168 (2)	0.055 (8)*
H2B	0.649 (4)	0.0435 (8)	−0.092 (3)	0.061 (9)*
H1B	0.434 (3)	0.2215 (11)	−0.1855 (17)	0.049 (8)*
H1A	0.544 (3)	0.2077 (11)	−0.071 (2)	0.053 (8)*

	U11	U22	U33	U12	U13	U23
Cr4	0.0280 (2)	0.0240 (2)	0.01765 (18)	0.000	−0.00312 (13)	0.000
O1	0.0307 (7)	0.0389 (7)	0.0229 (6)	0.0050 (5)	−0.0004 (5)	−0.0009 (5)
O2	0.0385 (7)	0.0280 (6)	0.0259 (6)	0.0010 (5)	−0.0071 (5)	0.0020 (5)
O3	0.0334 (6)	0.0290 (6)	0.0213 (5)	0.0013 (5)	−0.0020 (5)	0.0010 (4)
O4	0.0565 (9)	0.0310 (7)	0.0391 (8)	0.0071 (6)	−0.0026 (7)	0.0067 (6)
O5	0.0713 (11)	0.0278 (7)	0.0433 (8)	0.0053 (7)	−0.0084 (8)	0.0046 (6)
C1	0.0313 (9)	0.0293 (8)	0.0245 (8)	0.0015 (6)	0.0043 (6)	0.0013 (6)
C2	0.0358 (9)	0.0303 (8)	0.0272 (8)	0.0024 (7)	−0.0014 (7)	0.0024 (6)
N1	0.069 (2)	0.0486 (17)	0.071 (2)	0.000	0.0156 (17)	0.000
C3	0.0445 (13)	0.0814 (19)	0.0409 (12)	0.0074 (12)	−0.0084 (10)	0.0166 (12)
C4	0.0477 (19)	0.0471 (18)	0.062 (2)	0.000	0.0057 (16)	0.000
C5	0.0567 (15)	0.0726 (18)	0.0456 (13)	−0.0166 (13)	0.0001 (11)	−0.0139 (12)
O6	0.0303 (9)	0.0295 (9)	0.0514 (12)	0.000	−0.0067 (8)	0.000
N2	0.0520 (11)	0.0336 (9)	0.0434 (10)	−0.0022 (8)	−0.0052 (8)	−0.0043 (8)
C6	0.0291 (12)	0.0338 (12)	0.0346 (12)	0.000	0.0052 (10)	0.000

Cr4—O2i	1.9436 (12)	N1—C5ii	1.313 (3)
Cr4—O2	1.9436 (12)	N1—C5	1.313 (3)
Cr4—O3i	1.9762 (12)	N1—H1	0.8600
Cr4—O3	1.9762 (12)	C3—C5	1.341 (4)
Cr4—O1	1.9955 (14)	C3—C4	1.385 (3)
Cr4—O1i	1.9955 (14)	C3—H3	0.9300
O1—H1B	0.808 (16)	C4—C3ii	1.385 (3)
O1—H1A	0.808 (16)	C4—H4	0.9300
O2—C2	1.287 (2)	C5—H5	0.9300
O3—C1	1.287 (2)	O6—C6	1.260 (3)
O4—C1	1.217 (2)	N2—C6	1.331 (2)
O5—C2	1.216 (2)	N2—H2A	0.821 (17)
C1—C1i	1.559 (3)	N2—H2B	0.788 (17)
C2—C2i	1.556 (3)	C6—N2ii	1.331 (2)
O2i—Cr4—O2	83.43 (7)	O3—C1—C1i	113.91 (9)
O2i—Cr4—O3i	179.29 (5)	O5—C2—O2	125.43 (17)
O2—Cr4—O3i	97.10 (5)	O5—C2—C2i	120.99 (11)
O2i—Cr4—O3	97.10 (5)	O2—C2—C2i	113.59 (9)
O2—Cr4—O3	179.29 (5)	C5ii—N1—C5	121.0 (4)
O3i—Cr4—O3	82.36 (7)	C5ii—N1—H1	119.5
O2i—Cr4—O1	91.34 (6)	C5—N1—H1	119.5
O2—Cr4—O1	91.76 (6)	C5—C3—C4	119.2 (2)
O3i—Cr4—O1	89.11 (5)	C5—C3—H3	120.4
O3—Cr4—O1	87.76 (5)	C4—C3—H3	120.4
O2i—Cr4—O1i	91.76 (6)	C3—C4—C3ii	117.9 (4)
O2—Cr4—O1i	91.34 (6)	C3—C4—H4	121.1
O3i—Cr4—O1i	87.76 (5)	C3ii—C4—H4	121.1
O3—Cr4—O1i	89.11 (5)	N1—C5—C3	121.3 (3)
O1—Cr4—O1i	175.84 (8)	N1—C5—H5	119.3
Cr4—O1—H1B	117.8 (19)	C3—C5—H5	119.3
Cr4—O1—H1A	119.1 (19)	C6—N2—H2A	124 (2)
H1B—O1—H1A	108 (2)	C6—N2—H2B	116 (2)
C2—O2—Cr4	114.66 (11)	H2A—N2—H2B	119 (3)
C1—O3—Cr4	114.90 (10)	O6—C6—N2	121.10 (13)
O4—C1—O3	125.58 (16)	O6—C6—N2ii	121.10 (13)
O4—C1—C1i	120.51 (11)	N2—C6—N2ii	117.8 (3)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O4iii	0.86	2.26	2.979 (3)	142
N1—H1···O4iv	0.86	2.26	2.979 (3)	142
N2—H2A···O4v	0.82 (2)	2.36 (2)	3.134 (2)	158 (3)
N2—H2B···O5vi	0.79 (2)	2.08 (2)	2.847 (2)	166 (3)
O1—H1B···O3v	0.81 (2)	1.91 (2)	2.7135 (18)	174 (3)
O1—H1A···O6	0.81 (2)	1.79 (2)	2.5910 (16)	176 (3)

Table 1

Selected bond lengths (Å)

Cr4—O2	1.9436 (12)
Cr4—O3	1.9762 (12)
Cr4—O1	1.9955 (14)

Table 2

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O4i	0.86	2.26	2.979 (3)	142
N1—H1⋯O4ii	0.86	2.26	2.979 (3)	142
N2—H2A⋯O4iii	0.82 (2)	2.36 (2)	3.134 (2)	158 (3)
N2—H2B⋯O5iv	0.79 (2)	2.08 (2)	2.847 (2)	166 (3)
O1—H1B⋯O3iii	0.81 (2)	1.91 (2)	2.7135 (18)	174 (3)
O1—H1A⋯O6	0.81 (2)	1.79 (2)	2.5910 (16)	176 (3)

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) .