N,N′-(2-Ammonio­ethyl)ethane-1,2-diaminium di-μ-oxalato-bis­[aqua­oxalatocuprate(II)]

The asymmetric unit of the title compound, (C₆H₂₂N₄)[Cu₂(C₂O₄)₄(H₂O)₂], contains one-half of a C₆H₂₂N₄⁴⁺ cation and one-half of a [Cu₂(ox)₄(H₂O)₂]⁴⁻ anion (ox is oxalate). The [Cu(ox)₂(H₂O)]²⁻ units dimerize around an inversion center, giving an octa­hedrally distorted CuO₆ coordination. The cation is also centrosymmetric. Extensive hydrogen bonding between the oxalate, the coordinated water mol­ecules and the cations determines the crystal packing and may explain the strong inter­actions observed between the chelate Cu(ox)₂ planes of the [Cu₂(ox)₄(H₂O)₂]⁴⁻ anion.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.031
• wR factor = 0.079
• Data-to-parameter ratio = 13.2

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT029_ALERT_3_B _diffrn_measured_fraction_theta_full Low .......       0.95
PLAT232_ALERT_2_B Hirshfeld Test Diff (M-X)  Cu1    -   O9      ..      15.30 su

Alert level C
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.97
PLAT369_ALERT_2_C Long   C(sp2)-C(sp2) Bond  C1     -   C2     ...       1.55 Ang.
PLAT369_ALERT_2_C Long   C(sp2)-C(sp2) Bond  C3     -   C4     ...       1.55 Ang.

   0 ALERT level A = In general: serious problem
   2 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: SMART (Bruker,2000); cell refinement: SAINT (Bruker,2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL/PC (Sheldrick, 1999) and ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXTL/PC.

N,N'-(2-Ammonioethyl)ethane-1,2-diaminium di-µ₂-oxalato-bis[aquaoxalatocuprate(II)]

Crystal data

(C6H22N4)[Cu2(C2O4)4(H2O)2]	F(000) = 680
Mr = 665.47	Dx = 1.946 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2738 reflections
a = 9.736 (2) Å	θ = 2.4–26.8°
b = 14.089 (3) Å	µ = 1.97 mm^−1
c = 9.398 (2) Å	T = 298 K
β = 118.263 (2)°	Pillar, blue
V = 1135.4 (4) Å^3	0.30 × 0.20 × 0.20 mm
Z = 2

Data collection

Bruker SMART CCD area-detector diffractometer	2356 independent reflections
Radiation source: fine-focus sealed tube	1971 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.024
ω scans	θmax = 27.0°, θmin = 2.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 2000)	h = −12→12
Tmin = 0.589, Tmax = 0.694	k = −17→16
6026 measured reflections	l = −10→11

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.031	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.079	H atoms treated by a mixture of independent and constrained refinement
S = 0.98	w = 1/[σ^2(Fo^2) + (0.0472P)^2] where P = (Fo^2 + 2Fc^2)/3
2356 reflections	(Δ/σ)max = 0.001
179 parameters	Δρmax = 0.42 e Å^−3
3 restraints	Δρmin = −0.52 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Cu1	0.67072 (3)	0.447150 (19)	0.63152 (4)	0.02676 (12)
O1	0.87265 (17)	0.49937 (11)	0.6813 (2)	0.0283 (4)
O2	1.04204 (19)	0.60478 (12)	0.8485 (2)	0.0386 (5)
O3	0.68240 (19)	0.52977 (11)	0.8024 (2)	0.0306 (4)
O4	0.8555 (2)	0.62055 (12)	0.9963 (2)	0.0397 (4)
O5	0.66899 (18)	0.35806 (11)	0.4728 (2)	0.0316 (4)
O6	0.5435 (2)	0.22460 (13)	0.3603 (3)	0.0478 (5)
O7	0.45966 (17)	0.40441 (11)	0.5627 (2)	0.0279 (4)
O8	0.30585 (19)	0.28514 (12)	0.4191 (2)	0.0381 (4)
C1	0.9210 (3)	0.55863 (15)	0.7968 (3)	0.0266 (5)
C2	0.8119 (3)	0.57191 (16)	0.8734 (3)	0.0274 (5)
C3	0.4270 (3)	0.33036 (15)	0.4737 (3)	0.0265 (5)
C4	0.5565 (3)	0.30050 (16)	0.4309 (3)	0.0290 (5)
O9	0.8046 (2)	0.31789 (15)	0.8263 (2)	0.0443 (5)
H91	0.869 (3)	0.340 (2)	0.914 (2)	0.066*
H92	0.726 (2)	0.303 (2)	0.833 (4)	0.066*
C5	0.1162 (3)	0.34644 (18)	0.6109 (3)	0.0378 (6)
H5A	0.0486	0.3584	0.4969	0.045*
H5B	0.1915	0.2986	0.6196	0.045*
C6	0.2019 (3)	0.43683 (16)	0.6897 (3)	0.0323 (6)
H6A	0.2388	0.4663	0.6208	0.039*
H6B	0.1299	0.4805	0.6997	0.039*
C7	0.4265 (3)	0.51012 (17)	0.9218 (3)	0.0336 (6)
H7A	0.3618	0.5547	0.9419	0.040*
H7B	0.4538	0.5386	0.8446	0.040*
N1	0.0201 (2)	0.30836 (14)	0.6837 (3)	0.0349 (5)
H1A	0.0770	0.3074	0.7908	0.052*
H1B	−0.0109	0.2497	0.6478	0.052*
H1C	−0.0629	0.3453	0.6559	0.052*
N2	0.3378 (2)	0.42038 (14)	0.8535 (2)	0.0308 (5)
H2A	0.3033	0.3976	0.9203	0.037*
H2B	0.4016	0.3767	0.8461	0.037*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.02250 (18)	0.03177 (19)	0.02784 (19)	−0.00245 (11)	0.01340 (14)	−0.00609 (12)
O1	0.0242 (8)	0.0329 (9)	0.0296 (9)	−0.0022 (7)	0.0143 (7)	−0.0061 (7)
O2	0.0268 (9)	0.0410 (10)	0.0458 (12)	−0.0073 (8)	0.0154 (9)	−0.0117 (9)
O3	0.0281 (9)	0.0385 (9)	0.0302 (10)	−0.0045 (7)	0.0178 (8)	−0.0075 (8)
O4	0.0454 (11)	0.0445 (10)	0.0299 (10)	−0.0065 (8)	0.0182 (9)	−0.0117 (8)
O5	0.0261 (9)	0.0380 (9)	0.0343 (10)	−0.0050 (7)	0.0171 (8)	−0.0099 (8)
O6	0.0442 (11)	0.0421 (11)	0.0682 (15)	−0.0124 (9)	0.0357 (11)	−0.0261 (10)
O7	0.0221 (8)	0.0315 (9)	0.0315 (9)	−0.0018 (7)	0.0138 (7)	−0.0053 (7)
O8	0.0291 (9)	0.0384 (10)	0.0481 (12)	−0.0085 (8)	0.0194 (9)	−0.0105 (9)
C1	0.0245 (12)	0.0265 (12)	0.0280 (13)	0.0025 (9)	0.0118 (11)	0.0015 (10)
C2	0.0324 (13)	0.0259 (12)	0.0241 (13)	0.0035 (10)	0.0136 (11)	0.0022 (10)
C3	0.0265 (12)	0.0263 (12)	0.0266 (13)	0.0006 (10)	0.0125 (11)	0.0012 (10)
C4	0.0282 (13)	0.0314 (12)	0.0274 (13)	−0.0013 (10)	0.0130 (11)	−0.0039 (10)
O9	0.0385 (12)	0.0551 (12)	0.0390 (11)	−0.0131 (9)	0.0181 (9)	−0.0029 (10)
C5	0.0382 (14)	0.0477 (15)	0.0302 (14)	−0.0026 (12)	0.0183 (12)	−0.0048 (12)
C6	0.0322 (13)	0.0362 (14)	0.0319 (14)	0.0052 (11)	0.0179 (11)	0.0055 (11)
C7	0.0297 (13)	0.0324 (13)	0.0418 (16)	−0.0023 (11)	0.0194 (12)	0.0032 (12)
N1	0.0327 (12)	0.0323 (11)	0.0353 (12)	0.0000 (9)	0.0124 (10)	−0.0034 (9)
N2	0.0285 (11)	0.0317 (10)	0.0354 (13)	−0.0009 (8)	0.0178 (10)	0.0012 (9)

Geometric parameters (Å, º)

Cu1—O7	1.935 (2)	O9—H92	0.82 (3)
Cu1—O1	1.938 (2)	C5—N1	1.496 (3)
Cu1—O3	1.943 (2)	C5—C6	1.511 (3)
Cu1—O5	1.944 (2)	C5—H5A	0.9700
Cu1—O9	2.471 (2)	C5—H5B	0.9700
Cu1—Cu1^i	3.405 (1)	C6—N2	1.498 (3)
O1—C1	1.270 (3)	C6—H6A	0.9700
O2—C1	1.227 (3)	C6—H6B	0.9700
O3—C2	1.261 (3)	C7—N2	1.494 (3)
O4—C2	1.233 (3)	C7—C7^ii	1.516 (5)
O5—C4	1.266 (3)	C7—H7A	0.9700
O6—C4	1.233 (3)	C7—H7B	0.9700
O7—C3	1.279 (3)	N1—H1A	0.8900
O8—C3	1.219 (3)	N1—H1B	0.8900
C1—C2	1.551 (3)	N1—H1C	0.8900
C3—C4	1.553 (3)	N2—H2A	0.9000
O9—H91	0.82 (3)	N2—H2B	0.9000
O7—Cu1—O1	173.88 (7)	C6—C5—H5B	108.9
O7—Cu1—O3	95.74 (7)	H5A—C5—H5B	107.7
O1—Cu1—O3	85.26 (7)	N2—C6—C5	112.8 (2)
O7—Cu1—O5	85.44 (7)	N2—C6—H6A	109.0
O1—Cu1—O5	94.00 (6)	C5—C6—H6A	109.0
O3—Cu1—O5	175.80 (7)	N2—C6—H6B	109.0
C1—O1—Cu1	112.30 (14)	C5—C6—H6B	109.0
C2—O3—Cu1	111.81 (15)	H6A—C6—H6B	107.8
C4—O5—Cu1	110.13 (14)	N2—C7—C7^ii	110.2 (2)
C3—O7—Cu1	111.63 (14)	N2—C7—H7A	109.6
O2—C1—O1	125.8 (2)	C7^ii—C7—H7A	109.6
O2—C1—C2	119.5 (2)	N2—C7—H7B	109.6
O1—C1—C2	114.7 (2)	C7^ii—C7—H7B	109.6
O4—C2—O3	124.9 (2)	H7A—C7—H7B	108.1
O4—C2—C1	119.6 (2)	C5—N1—H1A	109.5
O3—C2—C1	115.5 (2)	C5—N1—H1B	109.5
O8—C3—O7	126.4 (2)	H1A—N1—H1B	109.5
O8—C3—C4	119.5 (2)	C5—N1—H1C	109.5
O7—C3—C4	114.14 (19)	H1A—N1—H1C	109.5
O6—C4—O5	125.2 (2)	H1B—N1—H1C	109.5
O6—C4—C3	119.0 (2)	C7—N2—C6	111.12 (18)
O5—C4—C3	115.8 (2)	C7—N2—H2A	109.4
H91—O9—H92	109 (2)	C6—N2—H2A	109.4
N1—C5—C6	113.4 (2)	C7—N2—H2B	109.4
N1—C5—H5A	108.9	C6—N2—H2B	109.4
C6—C5—H5A	108.9	H2A—N2—H2B	108.0
N1—C5—H5B	108.9

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2B···O6^iii	0.90	1.95	2.840 (3)	172
N2—H2A···O8^iii	0.90	2.57	3.007 (3)	110
N2—H2A···O4^ii	0.90	2.05	2.895 (3)	155
N1—H1C···O9^iv	0.89	2.52	2.979 (3)	113
N1—H1C···O5^iv	0.89	2.36	3.113 (3)	143
N1—H1C···O1^iv	0.89	2.30	3.045 (2)	141
N1—H1B···O2^v	0.89	2.07	2.917 (3)	160
N1—H1A···O8^iii	0.89	2.36	2.922 (3)	121
N1—H1A···O4^ii	0.89	2.05	2.840 (3)	147
O9—H92···O6^iii	0.82 (3)	1.95 (3)	2.773 (3)	175 (3)
O9—H91···O4^vi	0.82 (3)	2.46 (2)	3.043 (3)	128 (2)
O9—H91···O2^vi	0.82 (3)	2.12 (2)	2.905 (3)	158 (3)

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