trans-Bis(hydrogen maleato-κO)bis(pyridine-2-carboxamide-κ²N¹,O)copper(II)

In the title compound, [Cu(C₄H₃O₄)₂(C₆H₆N₂O)₂], the Cu^II atom lies on a centre of symmetry and adopts a 4+2 elongated octa­hedral geometry with two hydrogen maleate ligands in axial positions. The complex mol­ecules are linked via N—H...O hydrogen bonds into a two-dimensional network and further form a three-dimensional structure via weak C—H...O inter­actions.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.023
• wR factor = 0.072
• Data-to-parameter ratio = 11.1

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Cu     -   N1      ..       5.89 su
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C7
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        C10
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.06

Alert level G
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K

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

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

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Computing details

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED; program(s) used to solve structure: SIR2002 (Burla et al., 2003); program(s) used to refine structure: SHELXTL (Sheldrick, 2003); molecular graphics: Mercury (Macrae et al., 2006); software used to prepare material for publication: PLATON (Spek, 2003) and publCIF (Westrip, 2007).

trans-Bis(hydrogen maleato-κO)bis(pyridine-2-carboxamide-κ²N¹,O)copper(II)

Crystal data

[Cu(C4H3O4)2(C6H6N2O)2]	F(000) = 550
Mr = 537.93	Dx = 1.626 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 6086 reflections
a = 11.0611 (10) Å	θ = 3.0–28.9°
b = 12.6061 (9) Å	µ = 1.06 mm^−1
c = 7.8818 (6) Å	T = 293 K
β = 91.190 (8)°	Prism, blue
V = 1098.78 (15) Å^3	0.30 × 0.30 × 0.15 mm
Z = 2

Data collection

Kuma KM-4 CCD area-detector diffractometer	1917 independent reflections
Radiation source: CX-Mo12x0.4-S Seifert Mo tube	1638 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.017
Detector resolution: 8.2356 pixels mm^-1	θmax = 25.0°, θmin = 3.1°
ω scans	h = −13→10
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	k = −14→14
Tmin = 0.742, Tmax = 0.857	l = −9→9
9434 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: structure-invariant direct methods
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.023	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.072	w = 1/[σ^2(Fo^2) + (0.0452P)^2 + 0.083P] where P = (Fo^2 + 2Fc^2)/3
S = 1.14	(Δ/σ)max < 0.001
1917 reflections	Δρmax = 0.19 e Å^−3
173 parameters	Δρmin = −0.27 e Å^−3
0 restraints	Extinction correction: SHELXTL (Sheldrick, 2003), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0138 (16)

Special details

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

Refinement. Refinement on F² for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The observed criterion of F² > σ(F²) is used only for calculating -R-factor-obs 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
Cu	1.0000	0.0000	0.0000	0.03856 (14)
O1	0.95633 (11)	0.15112 (9)	−0.01833 (14)	0.0394 (3)
N1	1.12405 (13)	0.05559 (11)	0.15881 (17)	0.0363 (3)
N2	1.00579 (15)	0.31430 (12)	0.0719 (2)	0.0403 (4)
H21	0.950 (2)	0.3383 (16)	0.009 (2)	0.049 (6)*
H22	1.049 (2)	0.3567 (18)	0.133 (3)	0.062 (7)*
C1	1.02287 (15)	0.21194 (13)	0.0694 (2)	0.0335 (4)
C2	1.12450 (15)	0.16242 (12)	0.17043 (18)	0.0336 (4)
C3	1.21157 (16)	0.21582 (14)	0.2639 (2)	0.0413 (4)
H3	1.2118	0.2895	0.2689	0.050*
C4	1.29880 (17)	0.15702 (16)	0.3505 (2)	0.0494 (5)
H4	1.3581	0.1910	0.4159	0.059*
C5	1.29726 (17)	0.04871 (17)	0.3394 (2)	0.0487 (5)
H5	1.3555	0.0084	0.3967	0.058*
C6	1.20843 (18)	0.00006 (13)	0.2421 (3)	0.0450 (5)
H6	1.2075	−0.0736	0.2344	0.054*
O2	0.67825 (15)	0.27222 (12)	0.2760 (2)	0.0741 (5)
H2	0.733 (3)	0.215 (2)	0.316 (3)	0.099 (9)*
O3	0.51111 (17)	0.29352 (15)	0.1305 (3)	0.0951 (6)
O4	0.81568 (13)	0.12346 (11)	0.35161 (18)	0.0599 (4)
O5	0.85379 (13)	−0.03265 (11)	0.23404 (17)	0.0507 (3)
C7	0.59001 (19)	0.23517 (17)	0.1829 (3)	0.0582 (5)
C8	0.58628 (19)	0.12034 (19)	0.1457 (3)	0.0653 (6)
H8	0.5164	0.0987	0.0878	0.078*
C9	0.66429 (19)	0.04148 (17)	0.1794 (3)	0.0589 (6)
H9	0.6377	−0.0256	0.1466	0.071*
C10	0.78695 (16)	0.04426 (14)	0.2612 (2)	0.0398 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu	0.0436 (2)	0.02659 (19)	0.0447 (2)	0.00096 (12)	−0.01769 (13)	−0.00473 (11)
O1	0.0442 (7)	0.0292 (6)	0.0441 (6)	0.0014 (5)	−0.0167 (5)	−0.0049 (5)
N1	0.0391 (8)	0.0307 (8)	0.0388 (7)	0.0008 (6)	−0.0092 (6)	−0.0015 (6)
N2	0.0446 (9)	0.0297 (8)	0.0461 (8)	0.0022 (7)	−0.0159 (7)	−0.0053 (7)
C1	0.0357 (9)	0.0332 (9)	0.0316 (8)	−0.0006 (7)	−0.0033 (7)	−0.0029 (7)
C2	0.0341 (9)	0.0343 (9)	0.0324 (8)	−0.0004 (7)	−0.0035 (7)	−0.0023 (6)
C3	0.0417 (10)	0.0367 (9)	0.0449 (10)	−0.0031 (7)	−0.0095 (8)	−0.0063 (7)
C4	0.0399 (10)	0.0593 (13)	0.0486 (10)	−0.0066 (9)	−0.0141 (8)	−0.0047 (9)
C5	0.0401 (10)	0.0540 (12)	0.0513 (11)	0.0039 (9)	−0.0140 (8)	0.0049 (9)
C6	0.0474 (11)	0.0377 (10)	0.0493 (10)	0.0054 (8)	−0.0124 (9)	0.0029 (7)
O2	0.0663 (10)	0.0396 (8)	0.1151 (14)	0.0054 (8)	−0.0333 (10)	−0.0062 (8)
O3	0.0778 (12)	0.0805 (12)	0.1253 (15)	0.0327 (10)	−0.0400 (11)	0.0053 (11)
O4	0.0566 (9)	0.0492 (8)	0.0725 (9)	0.0047 (7)	−0.0315 (7)	−0.0122 (7)
O5	0.0511 (8)	0.0399 (7)	0.0609 (8)	0.0095 (6)	−0.0047 (6)	0.0075 (6)
C7	0.0473 (12)	0.0571 (13)	0.0696 (13)	0.0065 (10)	−0.0114 (10)	0.0061 (10)
C8	0.0424 (11)	0.0657 (14)	0.0867 (16)	0.0031 (10)	−0.0252 (11)	−0.0162 (12)
C9	0.0483 (12)	0.0463 (11)	0.0813 (15)	−0.0021 (10)	−0.0167 (11)	−0.0171 (11)
C10	0.0427 (10)	0.0333 (9)	0.0431 (9)	−0.0016 (8)	−0.0078 (8)	0.0068 (8)

Geometric parameters (Å, º)

Cu—O1	1.9699 (12)	C1—C2	1.500 (2)
Cu—O5	2.5123 (14)	C2—C3	1.376 (2)
Cu—N1	1.9670 (14)	C3—C4	1.385 (3)
O1—C1	1.260 (2)	C4—C5	1.368 (3)
O2—C7	1.296 (3)	C5—C6	1.378 (3)
O3—C7	1.208 (3)	C7—C8	1.477 (3)
O4—C10	1.263 (2)	C8—C9	1.339 (3)
O5—C10	1.241 (2)	C9—C10	1.490 (3)
O2—H2	0.99 (3)	C3—H3	0.93
N1—C2	1.350 (2)	C4—H4	0.93
N1—C6	1.329 (2)	C5—H5	0.93
N2—C1	1.304 (2)	C6—H6	0.93
N2—H22	0.86 (2)	C8—H8	0.93
N2—H21	0.84 (2)	C9—H9	0.93
O1—Cu—O5	92.96 (5)	N1—C6—C5	121.72 (16)
O1—Cu—N1	82.47 (5)	O2—C7—O3	120.3 (2)
O5—Cu—N1	92.43 (5)	O2—C7—C8	118.89 (19)
Cu—O1—C1	114.13 (11)	O3—C7—C8	120.8 (2)
Cu—O5—C10	113.19 (11)	C7—C8—C9	132.3 (2)
C7—O2—H2	111.5 (16)	C8—C9—C10	130.2 (2)
Cu—N1—C6	126.87 (12)	O4—C10—C9	118.60 (17)
C2—N1—C6	119.37 (15)	O5—C10—C9	116.58 (16)
Cu—N1—C2	113.59 (11)	O4—C10—O5	124.83 (17)
C1—N2—H21	116.9 (14)	C2—C3—H3	121
C1—N2—H22	123.1 (15)	C4—C3—H3	121
H21—N2—H22	120 (2)	C3—C4—H4	120
O1—C1—C2	117.45 (14)	C5—C4—H4	120
N2—C1—C2	120.72 (15)	C4—C5—H5	120
O1—C1—N2	121.82 (16)	C6—C5—H5	120
C1—C2—C3	126.09 (14)	N1—C6—H6	119
N1—C2—C1	112.18 (14)	C5—C6—H6	119
N1—C2—C3	121.73 (15)	C7—C8—H8	114
C2—C3—C4	118.33 (16)	C9—C8—H8	114
C3—C4—C5	119.66 (17)	C8—C9—H9	115
C4—C5—C6	119.18 (17)	C10—C9—H9	115

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···O4	0.99 (3)	1.50 (3)	2.479 (2)	172 (2)
N2—H21···O4^i	0.84 (2)	1.98 (2)	2.811 (2)	173 (2)
N2—H22···O5^ii	0.86 (2)	2.04 (2)	2.894 (2)	175 (2)
C3—H3···O5^ii	0.93	2.36	3.252 (2)	162
C4—H4···O3^iii	0.93	2.38	3.249 (3)	156
C6—H6···O2^iv	0.93	2.32	3.138 (2)	146

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