Diaqua-bis-(4-hy-droxy-5-nitro-pyridine-2-carboxyl-ato-κN,O)copper(II).

In the title compound, [Cu(C(6)H(3)N(2)O(5))(2)(H(2)O)(2)], the Cu(II) ion, lying on an inversion center, is coordinated by two pyridine N atoms and two carboxyl-ate O atoms from symmetry-related two 4-hy-droxy-5-nitro-pyridine-2-carboxyl-ate ligands, and two water mol-ecules, forming a distorted octa-hedral geometry. In the crystal, O-H⋯O hydrogen bonds link the complex mol-ecules. One of the H atoms of the water mol-ecule is disordered over two sites of equal occupancy.

Related literature

For complexes based on the 4-hy­droxy­lpyridine-2,6-dicarb­oxy­lic acid ligand, see: Zhao et al. (2006 ▶, 2009 ▶, 2011 ▶). For a similar reaction to the formation of the ligand, see: Xu et al. (2011 ▶).

Experimental

Crystal data

[Cu(C6H3N2O5)2(H2O)2]

M = 465.79

Monoclinic,

a = 6.5327 (7) Å

b = 9.7963 (10) Å

c = 12.2562 (12) Å

β = 102.86 (2)°

V = 764.68 (15) Å3

Z = 2

Mo Kα radiation

μ = 1.52 mm−1

T = 113 K

0.20 × 0.18 × 0.10 mm

Data collection

Rigaku Saturn 724 CCD diffractometer

Absorption correction: multi-scan (CrystalClear; Rigaku, 2005 ▶) T min = 0.752, T max = 0.863

9563 measured reflections

1829 independent reflections

1466 reflections with I > 2σ(I)

R int = 0.053

Refinement

R[F 2 > 2σ(F 2)] = 0.029

wR(F 2) = 0.077

S = 1.04

1829 reflections

149 parameters

6 restraints

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.39 e Å−3

Δρmin = −0.49 e Å−3

Data collection: CrystalClear (Rigaku, 2005 ▶); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXTL.

Crystal structure: contains datablock(s) global. DOI: 10.1107/S1600536811052949/hy2493sup1.cif

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

[Cu(C6H3N2O5)2(H2O)2]	F(000) = 470
Mr = 465.79	Dx = 2.023 Mg m−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 3085 reflections
a = 6.5327 (7) Å	θ = 2.1–27.9°
b = 9.7963 (10) Å	µ = 1.52 mm−1
c = 12.2562 (12) Å	T = 113 K
β = 102.86 (2)°	Prism, colorless
V = 764.68 (15) Å3	0.20 × 0.18 × 0.10 mm
Z = 2

Rigaku Saturn 724 CCD diffractometer	1829 independent reflections
Radiation source: rotating anode	1466 reflections with I > 2σ(I)
multilayer	Rint = 0.053
Detector resolution: 14.22 pixels mm-1	θmax = 27.9°, θmin = 2.7°
ω scans	h = −8→7
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	k = −12→12
Tmin = 0.752, Tmax = 0.863	l = −15→16
9563 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)] = 0.029	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.077	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ2(Fo2) + (0.036P)2] where P = (Fo2 + 2Fc2)/3
1829 reflections	(Δ/σ)max < 0.001
149 parameters	Δρmax = 0.39 e Å−3
6 restraints	Δρmin = −0.49 e Å−3

Experimental. Rigaku CrystalClear-SM Expert 2.0 r2

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.

	x	y	z	Uiso*/Ueq	Occ. (<1)
Cu1	0.0000	0.5000	0.5000	0.01573 (13)
O1	0.0540 (2)	0.53885 (14)	0.66132 (12)	0.0145 (3)
O2	0.1475 (2)	0.70789 (14)	0.78407 (11)	0.0150 (3)
O3	0.3093 (2)	1.08681 (14)	0.52856 (13)	0.0144 (3)
H3	0.331 (5)	1.107 (3)	0.592 (2)	0.058 (11)*
O4	0.2830 (3)	1.07679 (17)	0.31323 (14)	0.0291 (4)
O5	0.0819 (3)	0.9216 (2)	0.22215 (13)	0.0408 (5)
O6	0.3578 (3)	0.40247 (18)	0.52615 (15)	0.0253 (4)
H6A	0.371 (5)	0.381 (3)	0.5936 (10)	0.060 (11)*
H6B	0.454 (7)	0.455 (5)	0.516 (3)	0.06 (2)*	0.50
H6C	0.348 (10)	0.332 (3)	0.484 (3)	0.09 (3)*	0.50
N1	0.1030 (3)	0.68775 (16)	0.49202 (13)	0.0113 (4)
C1	0.1142 (3)	0.6591 (2)	0.68823 (16)	0.0121 (4)
C2	0.1493 (3)	0.7498 (2)	0.59364 (16)	0.0108 (4)
C3	0.2222 (3)	0.8799 (2)	0.61022 (16)	0.0109 (4)
H3A	0.2576	0.9169	0.6837	0.013*
C4	0.2450 (3)	0.9596 (2)	0.51800 (17)	0.0106 (4)
C5	0.1881 (3)	0.8957 (2)	0.41301 (16)	0.0114 (4)
C6	0.1219 (3)	0.7610 (2)	0.40323 (16)	0.0119 (4)
H6	0.0891	0.7197	0.3313	0.014*
N2	0.1874 (3)	0.97025 (17)	0.30795 (15)	0.0150 (4)

	U11	U22	U33	U12	U13	U23
Cu1	0.0276 (2)	0.00876 (18)	0.0110 (2)	−0.00692 (15)	0.00460 (15)	−0.00212 (14)
O1	0.0212 (8)	0.0095 (7)	0.0123 (8)	−0.0040 (6)	0.0028 (6)	0.0002 (5)
O2	0.0251 (8)	0.0103 (7)	0.0088 (7)	−0.0004 (6)	0.0021 (6)	−0.0006 (6)
O3	0.0201 (8)	0.0090 (7)	0.0146 (8)	−0.0040 (6)	0.0052 (7)	−0.0001 (6)
O4	0.0442 (11)	0.0199 (9)	0.0253 (9)	−0.0091 (8)	0.0124 (8)	0.0029 (7)
O5	0.0523 (13)	0.0497 (12)	0.0151 (9)	−0.0240 (10)	−0.0036 (9)	0.0070 (8)
O6	0.0271 (10)	0.0238 (9)	0.0234 (10)	−0.0057 (8)	0.0019 (8)	0.0029 (8)
N1	0.0125 (9)	0.0104 (8)	0.0100 (8)	−0.0010 (7)	0.0004 (7)	−0.0013 (6)
C1	0.0107 (10)	0.0107 (10)	0.0149 (11)	0.0005 (8)	0.0027 (8)	0.0031 (8)
C2	0.0123 (10)	0.0102 (9)	0.0091 (10)	0.0006 (8)	0.0006 (8)	0.0012 (7)
C3	0.0109 (10)	0.0116 (10)	0.0093 (10)	0.0000 (8)	0.0007 (8)	−0.0011 (7)
C4	0.0077 (9)	0.0100 (9)	0.0145 (10)	0.0007 (7)	0.0030 (8)	−0.0003 (7)
C5	0.0104 (10)	0.0139 (10)	0.0105 (10)	−0.0004 (8)	0.0034 (8)	0.0030 (8)
C6	0.0117 (11)	0.0149 (10)	0.0099 (10)	−0.0002 (8)	0.0036 (8)	−0.0028 (8)
N2	0.0150 (9)	0.0165 (9)	0.0136 (9)	−0.0015 (7)	0.0033 (8)	0.0011 (7)

Cu1—N1	1.9685 (16)	O6—H6C	0.85 (1)
Cu1—O1	1.9667 (15)	N1—C6	1.332 (2)
Cu1—O6	2.479 (2)	N1—C2	1.358 (2)
O1—C1	1.263 (2)	C1—C2	1.518 (3)
O2—C1	1.242 (2)	C2—C3	1.360 (3)
O3—C4	1.312 (2)	C3—C4	1.409 (3)
O3—H3	0.79 (3)	C3—H3A	0.9500
O4—N2	1.211 (2)	C4—C5	1.405 (3)
O5—N2	1.219 (2)	C5—C6	1.385 (3)
O6—H6A	0.84 (1)	C5—N2	1.480 (2)
O6—H6B	0.85 (1)	C6—H6	0.9500
O1—Cu1—O1i	180.0	O2—C1—C2	118.24 (17)
O1—Cu1—N1	83.24 (6)	O1—C1—C2	115.97 (17)
O1i—Cu1—N1	96.76 (6)	N1—C2—C3	123.75 (18)
O1—Cu1—N1i	96.76 (6)	N1—C2—C1	113.45 (17)
O1i—Cu1—N1i	83.24 (6)	C3—C2—C1	122.80 (18)
N1—Cu1—N1i	180.0	C2—C3—C4	119.73 (18)
O1—Cu1—O6	89.52 (6)	C2—C3—H3A	120.1
O1—Cu1—O6i	90.48 (6)	C4—C3—H3A	120.1
N1—Cu1—O6i	87.50 (7)	O3—C4—C5	121.85 (18)
O6—Cu1—N1	92.50 (7)	O3—C4—C3	122.42 (18)
O6—Cu1—O6i	180.00	C5—C4—C3	115.70 (18)
C1—O1—Cu1	114.76 (13)	C6—C5—C4	121.20 (18)
C4—O3—H3	109 (2)	C6—C5—N2	117.04 (17)
H6A—O6—H6B	112.7 (17)	C4—C5—N2	121.71 (17)
H6A—O6—H6C	111.5 (17)	N1—C6—C5	121.74 (18)
H6B—O6—H6C	111.2 (17)	N1—C6—H6	119.1
C6—N1—C2	117.79 (17)	C5—C6—H6	119.1
C6—N1—Cu1	129.69 (14)	O4—N2—O5	124.71 (18)
C2—N1—Cu1	112.42 (13)	O4—N2—C5	118.54 (17)
O2—C1—O1	125.79 (19)	O5—N2—C5	116.68 (17)
N1—Cu1—O1—C1	3.72 (14)	N1—C2—C3—C4	2.6 (3)
N1i—Cu1—O1—C1	−176.28 (14)	C1—C2—C3—C4	−178.09 (18)
O1—Cu1—N1—C6	−178.60 (18)	C2—C3—C4—O3	178.19 (18)
O1i—Cu1—N1—C6	1.40 (18)	C2—C3—C4—C5	0.1 (3)
O1—Cu1—N1—C2	−2.41 (13)	O3—C4—C5—C6	179.52 (18)
O1i—Cu1—N1—C2	177.59 (13)	C3—C4—C5—C6	−2.4 (3)
Cu1—O1—C1—O2	176.32 (16)	O3—C4—C5—N2	−3.1 (3)
Cu1—O1—C1—C2	−4.1 (2)	C3—C4—C5—N2	175.00 (17)
C6—N1—C2—C3	−3.0 (3)	C2—N1—C6—C5	0.5 (3)
Cu1—N1—C2—C3	−179.66 (16)	Cu1—N1—C6—C5	176.56 (14)
C6—N1—C2—C1	177.69 (16)	C4—C5—C6—N1	2.1 (3)
Cu1—N1—C2—C1	1.0 (2)	N2—C5—C6—N1	−175.38 (17)
O2—C1—C2—N1	−178.33 (17)	C6—C5—N2—O4	−165.03 (19)
O1—C1—C2—N1	2.1 (3)	C4—C5—N2—O4	17.5 (3)
O2—C1—C2—C3	2.3 (3)	C6—C5—N2—O5	18.0 (3)
O1—C1—C2—C3	−177.27 (18)	C4—C5—N2—O5	−159.5 (2)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O2ii	0.79 (3)	1.79 (3)	2.544 (2)	160 (3)
O6—H6A···O2iii	0.84 (1)	2.28 (2)	3.014 (2)	146 (3)
O6—H6B···O6iv	0.85 (1)	2.00 (1)	2.836 (3)	170 (5)
O6—H6C···O3v	0.85 (1)	2.49 (3)	3.109 (2)	130 (3)

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3⋯O2i	0.79 (3)	1.79 (3)	2.544 (2)	160 (3)
O6—H6A⋯O2ii	0.84 (1)	2.28 (2)	3.014 (2)	146 (3)
O6—H6B⋯O6iii	0.85 (1)	2.00 (1)	2.836 (3)	170 (5)
O6—H6C⋯O3iv	0.85 (1)	2.49 (3)	3.109 (2)	130 (3)

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