Tetra­aqua­(4-hydroxy­pyridine-2,6-dicarboxyl­ato)cobalt(II)

The title compound, [Co(C₇H₄NO₄)₂(H₂O)₄], consists of one cobalt cation, two 4-hydroxy­pyridine-2,6-dicarboxyl­ate ligands, and four coordinated water mol­ecules. The geometry around the cobalt(II) cation, which is located on a centre of inversion, is distorted octa­hedral. The four coordinated water mol­ecules and the hydroxyl atoms from the ligand form inter­molecular hydrogen bonds, resulting in a three-dimensional supra­molecular network.

Key indicators

• Single-crystal X-ray study
• T = 294 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.025
• wR factor = 0.069
• Data-to-parameter ratio = 10.9

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.52
PLAT369_ALERT_2_C Long   C(sp2)-C(sp2) Bond  C6     -   C7     ...       1.53 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
   0 ALERT type 5 Informative message, check

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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.

Tetraaqua(4-hydroxypyridine-2,6-dicarboxylato)cobalt(II)

Crystal data

[Co(C7H4NO4)2(H2O)4]	F(000) = 506
Mr = 495.22	Dx = 1.838 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3277 reflections
a = 5.3747 (8) Å	θ = 2.3–26.3°
b = 10.8834 (16) Å	µ = 1.05 mm^−1
c = 15.342 (2) Å	T = 294 K
β = 94.496 (2)°	Block, red
V = 894.7 (2) Å^3	0.18 × 0.10 × 0.06 mm
Z = 2

Data collection

Bruker SMART CCD area-detector diffractometer	1578 independent reflections
Radiation source: fine-focus sealed tube	1434 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.023
φ and ω scans	θmax = 25.0°, θmin = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −5→6
Tmin = 0.834, Tmax = 0.940	k = −11→12
4447 measured reflections	l = −18→17

Refinement

Refinement on F^2	3 restraints
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F^2 > 2σ(F^2)] = 0.025	w = 1/[σ^2(Fo^2) + (0.0351P)^2 + 0.3708P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.069	(Δ/σ)max = 0.003
S = 1.10	Δρmax = 0.25 e Å^−3
1578 reflections	Δρmin = −0.29 e Å^−3
145 parameters

Special details

Experimental. IR (KBr, ν, cm^-1): 3400 (s), 3285 (s), 2729 (w), 2619 (w), 2514 (w); 2345 (w), 1603 (s), 1464 (m), 1386 (s), 1330 (m), 1264 (m), 1122 (m), 1057 (s), 932 (m), 870 (m), 744 (m).

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
Co1	0.0000	0.0000	0.0000	0.02496 (14)
O1	0.1594 (3)	0.15079 (12)	0.06421 (9)	0.0325 (3)
O2	−0.0382 (3)	0.31660 (13)	0.00630 (10)	0.0388 (4)
O3	0.5925 (3)	0.64238 (11)	0.12910 (9)	0.0345 (3)
H3	0.7053	0.6668	0.1633	0.041*
O4	1.0601 (2)	0.27080 (12)	0.28515 (9)	0.0340 (3)
O5	0.8005 (3)	0.12334 (12)	0.23449 (9)	0.0339 (3)
O6	−0.2123 (2)	−0.04491 (12)	0.10686 (8)	0.0300 (3)
H6A	−0.2095	0.0113	0.1437	0.036*
H6B	−0.1466	−0.1123	0.1309	0.036*
O7	0.2869 (3)	−0.11110 (13)	0.05331 (11)	0.0441 (4)
H7A	0.2458	−0.1849	0.0425	0.053*
H7B	0.4408	−0.0967	0.0664	0.053*
N1	0.5013 (3)	0.27650 (14)	0.14863 (10)	0.0235 (3)
H1	0.475 (4)	0.200 (2)	0.1512 (13)	0.028*
C1	0.1295 (3)	0.26442 (17)	0.05090 (11)	0.0238 (4)
C2	0.3331 (3)	0.34164 (16)	0.09845 (11)	0.0229 (4)
C3	0.3605 (3)	0.46596 (17)	0.09262 (12)	0.0252 (4)
H3A	0.2447	0.5126	0.0587	0.030*
C4	0.5660 (3)	0.52231 (16)	0.13853 (12)	0.0254 (4)
C5	0.7348 (3)	0.45014 (18)	0.19074 (12)	0.0265 (4)
H5	0.8702	0.4863	0.2224	0.032*
C6	0.6981 (3)	0.32614 (16)	0.19460 (11)	0.0233 (4)
C7	0.8677 (3)	0.23168 (16)	0.24284 (11)	0.0243 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Co1	0.0194 (2)	0.0163 (2)	0.0373 (2)	−0.00274 (13)	−0.00991 (14)	0.00127 (14)
O1	0.0321 (7)	0.0173 (7)	0.0451 (8)	−0.0046 (5)	−0.0145 (6)	−0.0003 (6)
O2	0.0316 (8)	0.0238 (8)	0.0570 (9)	−0.0013 (6)	−0.0221 (7)	0.0019 (6)
O3	0.0320 (7)	0.0182 (7)	0.0503 (9)	−0.0066 (5)	−0.0164 (6)	0.0036 (6)
O4	0.0292 (7)	0.0258 (7)	0.0438 (8)	0.0044 (6)	−0.0167 (6)	−0.0039 (6)
O5	0.0358 (8)	0.0206 (7)	0.0433 (8)	0.0012 (6)	−0.0097 (6)	0.0009 (6)
O6	0.0300 (7)	0.0210 (7)	0.0377 (7)	−0.0008 (6)	−0.0065 (6)	0.0008 (6)
O7	0.0259 (7)	0.0219 (8)	0.0804 (11)	−0.0017 (6)	−0.0217 (7)	0.0033 (7)
N1	0.0222 (8)	0.0156 (8)	0.0316 (8)	−0.0015 (6)	−0.0056 (6)	0.0000 (6)
C1	0.0213 (9)	0.0205 (10)	0.0288 (9)	−0.0030 (7)	−0.0031 (7)	−0.0017 (7)
C2	0.0193 (8)	0.0211 (9)	0.0274 (9)	−0.0009 (7)	−0.0031 (7)	−0.0005 (7)
C3	0.0220 (9)	0.0197 (9)	0.0323 (10)	−0.0003 (7)	−0.0068 (7)	0.0028 (8)
C4	0.0254 (9)	0.0176 (9)	0.0323 (10)	−0.0031 (7)	−0.0026 (8)	−0.0002 (8)
C5	0.0224 (9)	0.0226 (10)	0.0326 (10)	−0.0026 (7)	−0.0088 (7)	−0.0015 (8)
C6	0.0207 (9)	0.0225 (10)	0.0257 (9)	−0.0005 (7)	−0.0040 (7)	−0.0009 (7)
C7	0.0249 (9)	0.0204 (10)	0.0270 (9)	0.0039 (7)	−0.0024 (7)	−0.0019 (7)

Geometric parameters (Å, º)

Co1—O1	2.0653 (12)	O7—H7A	0.8457
Co1—O1^i	2.0653 (12)	O7—H7B	0.8499
Co1—O7^i	2.0764 (13)	N1—C6	1.338 (2)
Co1—O7	2.0764 (13)	N1—C2	1.343 (2)
Co1—O6^i	2.1266 (13)	N1—H1	0.84 (2)
Co1—O6	2.1266 (13)	C1—C2	1.520 (2)
O1—C1	1.262 (2)	C2—C3	1.365 (3)
O2—C1	1.227 (2)	C3—C4	1.404 (3)
O3—C4	1.324 (2)	C3—H3A	0.9300
O3—H3	0.8149	C4—C5	1.403 (3)
O4—C7	1.251 (2)	C5—C6	1.366 (3)
O5—C7	1.237 (2)	C5—H5	0.9300
O6—H6A	0.8327	C6—C7	1.526 (2)
O6—H6B	0.8820
O1—Co1—O1^i	180.00 (7)	C6—N1—H1	120.2 (14)
O1—Co1—O7^i	89.58 (5)	C2—N1—H1	115.9 (14)
O1^i—Co1—O7^i	90.42 (5)	O2—C1—O1	128.51 (17)
O1—Co1—O7	90.42 (5)	O2—C1—C2	118.77 (16)
O1^i—Co1—O7	89.58 (5)	O1—C1—C2	112.72 (15)
O7^i—Co1—O7	180.0	N1—C2—C3	119.33 (16)
O1—Co1—O6^i	87.56 (5)	N1—C2—C1	114.22 (15)
O1^i—Co1—O6^i	92.44 (5)	C3—C2—C1	126.43 (16)
O7^i—Co1—O6^i	89.39 (6)	C2—C3—C4	119.00 (17)
O7—Co1—O6^i	90.61 (6)	C2—C3—H3A	120.5
O1—Co1—O6	92.44 (5)	C4—C3—H3A	120.5
O1^i—Co1—O6	87.56 (5)	O3—C4—C5	123.02 (17)
O7^i—Co1—O6	90.61 (6)	O3—C4—C3	117.62 (17)
O7—Co1—O6	89.39 (6)	C5—C4—C3	119.35 (17)
O6^i—Co1—O6	180.0	C6—C5—C4	119.27 (17)
C1—O1—Co1	131.21 (12)	C6—C5—H5	120.4
C4—O3—H3	109.4	C4—C5—H5	120.4
Co1—O6—H6A	111.9	N1—C6—C5	119.13 (16)
Co1—O6—H6B	107.0	N1—C6—C7	113.64 (15)
H6A—O6—H6B	110.0	C5—C6—C7	127.13 (16)
Co1—O7—H7A	107.5	O5—C7—O4	126.93 (17)
Co1—O7—H7B	131.6	O5—C7—C6	115.66 (15)
H7A—O7—H7B	117.1	O4—C7—C6	117.39 (16)
C6—N1—C2	123.90 (16)
O7^i—Co1—O1—C1	−19.05 (17)	C1—C2—C3—C4	−177.46 (17)
O7—Co1—O1—C1	160.95 (17)	C2—C3—C4—O3	177.61 (17)
O6^i—Co1—O1—C1	70.36 (17)	C2—C3—C4—C5	−1.4 (3)
O6—Co1—O1—C1	−109.64 (17)	O3—C4—C5—C6	−177.84 (17)
Co1—O1—C1—O2	15.5 (3)	C3—C4—C5—C6	1.2 (3)
Co1—O1—C1—C2	−164.85 (12)	C2—N1—C6—C5	−0.5 (3)
C6—N1—C2—C3	0.2 (3)	C2—N1—C6—C7	−177.25 (16)
C6—N1—C2—C1	178.64 (16)	C4—C5—C6—N1	−0.2 (3)
O2—C1—C2—N1	177.08 (17)	C4—C5—C6—C7	176.07 (17)
O1—C1—C2—N1	−2.7 (2)	N1—C6—C7—O5	−1.1 (2)
O2—C1—C2—C3	−4.6 (3)	C5—C6—C7—O5	−177.53 (18)
O1—C1—C2—C3	175.66 (18)	N1—C6—C7—O4	177.86 (16)
N1—C2—C3—C4	0.8 (3)	C5—C6—C7—O4	1.4 (3)

Symmetry code: (i) −x, −y, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1	0.85 (2)	2.14 (2)	2.560 (2)	110.1 (17)
N1—H1···O5	0.85 (2)	2.25 (2)	2.602 (2)	105.5 (17)
O3—H3···O4^ii	0.81	1.83	2.6049 (19)	159
O6—H6A···O5^iii	0.83	1.85	2.6778 (19)	174
O6—H6B···O4^iv	0.88	1.84	2.6878 (19)	159
O7—H7A···O2^i	0.85	1.93	2.727 (2)	156
O7—H7B···O6^v	0.85	2.00	2.845 (2)	172
C3—H3A···O2^vi	0.93	2.35	3.239 (2)	161
C5—H5···O5^ii	0.93	2.37	3.265 (2)	162

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