Diaqua­bis(pyridine-2,3-dicarboxyl­ato)copper(II)

The centrosymmetric title copper(II) complex, [Cu(C₇H₄NO₄)₂(H₂O)₂], was synthesized via the hydro­thermal method at a mild temperature (353 K). The Cu^II ion has a distorted octa­hedral coordination environment, with two N and two O atoms from the pyridine-2,3-dicarboxyl­ate ligands in a common plane and with two water mol­ecules in axial positions. Hydrogen bonds play an important role in the formation of the three-dimensional structure.

Key indicators

• Single-crystal X-ray study
• T = 273 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.030
• wR factor = 0.099
• Data-to-parameter ratio = 13.8

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.01
PLAT369_ALERT_2_C Long   C(sp2)-C(sp2) Bond  C5     -   C7_a   ...       1.54 Ang.

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 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

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Computing details

Data collection: SMART (Bruker, 1997); cell refinement: SMART; data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1997); software used to prepare material for publication: SHELXTL.

Diaquabis(pyridine-2,3-dicarboxylato)copper(II)

Crystal data

[Cu(C7H4NO4)2(H2O)2]	Z = 2
Mr = 431.80	F(000) = 438
Monoclinic, P21/n	Dx = 1.905 Mg m^−3
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 9.2115 (8) Å	µ = 1.52 mm^−1
b = 7.9171 (6) Å	T = 273 K
c = 10.3631 (9) Å	Block, blue
β = 94.945 (1)°	0.25 × 0.16 × 0.1 mm
V = 752.95 (11) Å^3

Data collection

Bruker SMART CCD area-detector diffractometer	1802 independent reflections
Radiation source: fine-focus sealed tube	1706 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.012
φ and ω scans	θmax = 28.0°, θmin = 2.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −12→12
Tmin = 0.703, Tmax = 0.863	k = −10→9
4841 measured reflections	l = −13→11

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.030	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.099	w = 1/[σ^2(Fo^2) + (0.0615P)^2 + 0.6891P] where P = (Fo^2 + 2Fc^2)/3
S = 1.04	(Δ/σ)max < 0.001
1802 reflections	Δρmax = 0.47 e Å^−3
131 parameters	Δρmin = −0.68 e Å^−3
1 restraint	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.015 (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	1.0000	0.0000	0.0000	0.02140 (16)
O1	1.13793 (14)	0.15981 (16)	−0.07950 (14)	0.0233 (3)
O4	0.36886 (15)	0.24046 (19)	0.18816 (16)	0.0319 (3)
N1	0.83654 (16)	0.16005 (19)	0.03644 (15)	0.0200 (3)
C1	0.8406 (2)	0.3251 (2)	0.01111 (19)	0.0254 (4)
H1	0.9203	0.3691	−0.0269	0.030*
C2	0.7298 (2)	0.4323 (2)	0.0398 (2)	0.0290 (4)
H2	0.7344	0.5474	0.0229	0.035*
C3	0.6125 (2)	0.3639 (2)	0.09412 (19)	0.0257 (4)
H3	0.5369	0.4343	0.1144	0.031*
C4	0.60387 (19)	0.1909 (2)	0.11968 (17)	0.0196 (4)
C5	0.72218 (18)	0.0917 (2)	0.08963 (16)	0.0179 (3)
C6	0.46496 (19)	0.1355 (2)	0.17667 (18)	0.0239 (4)
C7	1.25601 (19)	0.0997 (2)	−0.10779 (17)	0.0193 (3)
O6	1.35512 (15)	0.18855 (18)	−0.14866 (15)	0.0293 (3)
O3	0.4475 (2)	−0.0181 (2)	0.2111 (2)	0.0400 (5)
H4	0.5146	−0.0759	0.1883	0.048*
O5	1.10248 (15)	0.0548 (2)	0.18573 (14)	0.0268 (3)
H5	1.172 (2)	0.115 (3)	0.181 (2)	0.032*
H6	1.122 (3)	−0.0372 (19)	0.216 (3)	0.032*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.0163 (2)	0.0189 (2)	0.0299 (2)	0.00089 (9)	0.00742 (14)	0.00036 (10)
O1	0.0187 (6)	0.0178 (6)	0.0346 (7)	0.0011 (5)	0.0093 (5)	0.0018 (5)
O4	0.0181 (6)	0.0340 (8)	0.0449 (8)	0.0032 (5)	0.0098 (6)	−0.0064 (6)
N1	0.0166 (7)	0.0172 (7)	0.0267 (7)	0.0007 (5)	0.0058 (6)	−0.0005 (6)
C1	0.0239 (9)	0.0197 (8)	0.0339 (9)	−0.0006 (7)	0.0100 (7)	0.0018 (7)
C2	0.0304 (10)	0.0179 (9)	0.0396 (10)	0.0038 (7)	0.0081 (8)	0.0031 (7)
C3	0.0228 (9)	0.0236 (9)	0.0314 (9)	0.0081 (7)	0.0057 (7)	−0.0002 (7)
C4	0.0159 (8)	0.0232 (8)	0.0199 (8)	0.0011 (6)	0.0028 (6)	−0.0015 (6)
C5	0.0169 (8)	0.0164 (8)	0.0205 (8)	0.0003 (6)	0.0017 (6)	−0.0002 (6)
C6	0.0169 (8)	0.0297 (9)	0.0256 (8)	0.0002 (7)	0.0050 (6)	−0.0048 (7)
C7	0.0188 (8)	0.0168 (8)	0.0224 (8)	0.0001 (6)	0.0028 (6)	0.0000 (6)
O6	0.0227 (7)	0.0207 (6)	0.0463 (8)	−0.0026 (5)	0.0142 (6)	0.0027 (6)
O3	0.0261 (9)	0.0318 (9)	0.0657 (13)	0.0028 (6)	0.0255 (8)	0.0047 (7)
O5	0.0218 (7)	0.0280 (7)	0.0309 (7)	−0.0034 (6)	0.0037 (5)	0.0015 (6)

Geometric parameters (Å, º)

Cu1—O1^i	2.0185 (13)	C2—H2	0.9300
Cu1—O1	2.0185 (13)	C3—C4	1.399 (3)
Cu1—N1	2.0282 (15)	C3—H3	0.9300
Cu1—N1^i	2.0282 (15)	C4—C5	1.400 (2)
Cu1—O5^i	2.1144 (14)	C4—C6	1.520 (2)
Cu1—O5	2.1144 (14)	C5—C7^i	1.538 (3)
O1—C7	1.245 (2)	C6—O3	1.281 (2)
O4—C6	1.228 (2)	C7—O6	1.255 (2)
N1—C1	1.334 (2)	C7—C5^i	1.538 (3)
N1—C5	1.344 (2)	O3—H4	0.8200
C1—C2	1.380 (3)	O5—H5	0.806 (10)
C1—H1	0.9300	O5—H6	0.807 (10)
C2—C3	1.372 (3)
O1^i—Cu1—O1	180.00 (10)	C3—C2—C1	118.00 (17)
O1^i—Cu1—N1	79.17 (6)	C3—C2—H2	121.0
O1—Cu1—N1	100.83 (6)	C1—C2—H2	121.0
O1^i—Cu1—N1^i	100.83 (6)	C2—C3—C4	121.57 (17)
O1—Cu1—N1^i	79.17 (6)	C2—C3—H3	119.2
N1—Cu1—N1^i	180.00 (9)	C4—C3—H3	119.2
O1^i—Cu1—O5^i	89.74 (5)	C3—C4—C5	116.71 (16)
O1—Cu1—O5^i	90.26 (5)	C3—C4—C6	114.84 (16)
N1—Cu1—O5^i	91.00 (6)	C5—C4—C6	128.45 (17)
N1^i—Cu1—O5^i	89.00 (6)	N1—C5—C4	121.19 (16)
O1^i—Cu1—O5	90.26 (5)	N1—C5—C7^i	110.37 (13)
O1—Cu1—O5	89.74 (5)	C4—C5—C7^i	128.43 (15)
N1—Cu1—O5	89.00 (6)	O4—C6—O3	120.44 (18)
N1^i—Cu1—O5	91.00 (6)	O4—C6—C4	118.71 (18)
O5^i—Cu1—O5	180.00 (9)	O3—C6—C4	120.85 (17)
C7—O1—Cu1	116.75 (12)	O1—C7—O6	122.78 (17)
C1—N1—C5	120.76 (15)	O1—C7—C5^i	117.07 (14)
C1—N1—Cu1	122.78 (12)	O6—C7—C5^i	120.15 (15)
C5—N1—Cu1	116.45 (12)	C6—O3—H4	109.5
N1—C1—C2	121.75 (17)	Cu1—O5—H5	110.9 (18)
N1—C1—H1	119.1	Cu1—O5—H6	104 (2)
C2—C1—H1	119.1	H5—O5—H6	114 (3)
N1—Cu1—O1—C7	176.64 (13)	C2—C3—C4—C5	1.3 (3)
N1^i—Cu1—O1—C7	−3.36 (13)	C2—C3—C4—C6	−178.47 (18)
O5^i—Cu1—O1—C7	−92.29 (13)	C1—N1—C5—C4	0.2 (3)
O5—Cu1—O1—C7	87.71 (13)	Cu1—N1—C5—C4	179.51 (12)
O1^i—Cu1—N1—C1	178.37 (16)	C1—N1—C5—C7^i	179.58 (16)
O1—Cu1—N1—C1	−1.63 (16)	Cu1—N1—C5—C7^i	−1.12 (18)
O5^i—Cu1—N1—C1	−92.08 (15)	C3—C4—C5—N1	−1.3 (3)
O5—Cu1—N1—C1	87.92 (15)	C6—C4—C5—N1	178.43 (16)
O1^i—Cu1—N1—C5	−0.91 (12)	C3—C4—C5—C7^i	179.46 (16)
O1—Cu1—N1—C5	179.09 (12)	C6—C4—C5—C7^i	−0.8 (3)
O5^i—Cu1—N1—C5	88.64 (13)	C3—C4—C6—O4	4.6 (3)
O5—Cu1—N1—C5	−91.36 (13)	C5—C4—C6—O4	−175.18 (17)
C5—N1—C1—C2	0.9 (3)	C3—C4—C6—O3	−176.05 (19)
Cu1—N1—C1—C2	−178.30 (15)	C5—C4—C6—O3	4.2 (3)
N1—C1—C2—C3	−0.9 (3)	Cu1—O1—C7—O6	−174.55 (14)
C1—C2—C3—C4	−0.2 (3)	Cu1—O1—C7—C5^i	4.97 (19)

Symmetry code: (i) −x+2, −y, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O5—H6···O4^ii	0.81 (1)	2.02 (1)	2.813 (2)	167 (3)
O3—H4···O6^i	0.82	1.58	2.398 (2)	178
O5—H5···O4^iii	0.81 (1)	2.06 (1)	2.859 (2)	171 (3)

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