Bis[μ-(2-carboxyl­atoeth­yl)phospho­nato]­bis­[aqua­(2,2′-bipyridine)cobalt(II)]

The title compound, [Co₂(HO₃PCH₂CH₂COO)₂(C₁₀H₈N₂)₂(H₂O)₂], was obtained by a hydro­thermal method. Two six-coordinate cobalt(II) ions are linked by two 2-carboxy­ethyl­phospho­nate ligands, forming a centrosymmetric dimer. The dimers are further inter­linked by O—H...O hydrogen bonds and π–π stacking [centroid–centroid distance = 4.2975 (5) Å] to form a three-dimensional supramol­ecular structure. The compound is isostructural with the analogous zinc(II) complex reported recently [Ying, Li, Chen, Liu & Liu (2007). Acta Cryst. E63, m555–m557].

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.029
• wR factor = 0.070
• Data-to-parameter ratio = 18.9

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT415_ALERT_2_B Short Inter D-H..H-X       H3A    ..  H6A     ..       1.97 Ang.

Alert level C
GOODF01_ALERT_2_C  The least squares goodness of fit parameter lies
            outside the range 0.80 <> 2.00
            Goodness of fit given =      0.781
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Co1    -   O4      ..       7.99 su

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
PLAT793_ALERT_1_G Check the Absolute Configuration of P1     = ...          R
PLAT794_ALERT_5_G Check Predicted Bond Valency for Co1         (9)       1.74

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

   3 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
   0 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

Recently, the chemistry of metal phosphonates has been a research field of rapid expansion, mainly due to their potential application in the area of catalysis, ion exchange, proton conductivity, intercalation chemistry, photochemistry and material chemistry (Clearfield 1998). Many metal phosphonates have been reported (Cheetham et al., 1999; Stock et al., 2000; Serpaggi & Férey, 1999; Ying & Mao, 2004; Ying et al., 2006). The metal phosphonates can exhibit various kinds of structure. We report here the crystal structure of a new cobalt(II) carboxyalkylphosphonate complex synthesized by the hydrothermal method.

The asymmetric unit of the title compound contains one cobalt(II) ion, one doubly deprotonated 2-carboxyethylphosphonic acid ligand, one 2,2'-bipyridine and one coordinated water molecule. The cobalt(II) ion is six-coordinated by one phosphonate oxygen atom, one water molecule, two carboxylate oxygen atoms and two N atoms of a 2,2'-bipyridine molecule. The Co—O distances range from 2.0076 (13) to 2.2112 (15) Å and the Co—N distances are 2.1038 (16) and 2.1471 (17) Å. Two cobalt(II) ions are linked by two 2-carboxyethylphosphonic acid ligands forming a dimer (Fig. 1). The dimers are further interlinked by O—H···O hydrogen bonds (Table 1) and π-π stacking interactions to form a three-dimensional supermolecular structure (Fig. 2). The compound is isostructural with the analogous zinc(II) complex reported recently (Ying et al., 2007).

Related literature

For related literature, see: Clearfield (1998); Cheetham et al. (1999); Stock et al. (2000); Serpaggi & Férey (1999); Ying & Mao (2004); Ying et al. (2006, 2007).

S2. Experimental

A mixture of cobalt(II) acetate (0.5 mmol, 0.123 g), 2-carboxyethylphosphonic acid (0.5 mmol, 0.078 g), and 2,2'-bipyridine (0.5 mmol, 0.078 g) in 10 ml of distilled water was sealed in an autoclave equipped with a Teflon liner (20 ml) and then heated at 160°C for 4 days. Crystals of the title compound were obtained.

S3. Refinement

All hydrogen atoms were positioned geometrically and with C—H = 0.93–0.98 Å, O—H = 0.82 Å, and refined in the riding-model approximation, with U_iso(H) = 1.2 U_eq(C) or 1.5 U_eq(O).

Computing details

Data collection: SMART (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a); molecular graphics: SHELXTL (Sheldrick, 1997b); software used to prepare material for publication: SHELXTL (Sheldrick, 1997b).

Figures

	Fig. 1. The molecular structure of the title compound with displacement ellipsoids drawn at the 50% probability level. [Symmetry code: (A) 2 - x, 1 - y, 1 - z.]
	Fig. 2. Packing diagram of the title compound viewed along the a axis. Hydrogen atoms are omitted for clarity.

Bis[µ-(2-carboxylatoethyl)phosphonato]bis[aqua(2,2'-bipyridine)cobalt(II)]

Crystal data

[Co2(C3H5O5P)2(C10H8N2)2(H2O)2]	F(000) = 1576
Mr = 770.34	Dx = 1.623 Mg m^−3
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 7543 reflections
a = 8.6384 (18) Å	θ = 2.3–28.2°
b = 17.701 (4) Å	µ = 1.22 mm^−1
c = 20.619 (4) Å	T = 293 K
V = 3152.8 (11) Å^3	Plate, pink
Z = 4	0.34 × 0.33 × 0.06 mm

Data collection

Bruker APEX area-detector diffractometer	3924 independent reflections
Radiation source: fine-focus sealed tube	2241 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.044
φ and ω scans	θmax = 28.4°, θmin = 2.0°
Absorption correction: multi-scan (SADABS; Sheldrick, 2002)	h = −11→10
Tmin = 0.682, Tmax = 0.930	k = −23→23
22346 measured reflections	l = −26→27

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)] = 0.029	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.070	H-atom parameters constrained
S = 0.78	w = 1/[σ^2(Fo^2) + (0.0378P)^2] where P = (Fo^2 + 2Fc^2)/3
3924 reflections	(Δ/σ)max = 0.025
208 parameters	Δρmax = 0.49 e Å^−3
0 restraints	Δρmin = −0.53 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
Co1	0.67017 (3)	0.427251 (15)	0.405818 (12)	0.02945 (9)
P1	1.15669 (6)	0.69676 (3)	0.49404 (3)	0.03041 (14)
N1	0.7003 (2)	0.38302 (10)	0.31196 (8)	0.0380 (5)
N2	0.5524 (2)	0.50685 (9)	0.34466 (8)	0.0379 (4)
O5	0.87439 (17)	0.50256 (8)	0.40645 (6)	0.0410 (4)
O4	0.69834 (16)	0.51179 (8)	0.48183 (7)	0.0383 (4)
O3	1.05769 (16)	0.76527 (7)	0.50687 (7)	0.0429 (4)
O2	1.21917 (16)	0.66098 (7)	0.55427 (6)	0.0360 (4)
O1	1.28912 (17)	0.71919 (8)	0.44566 (7)	0.0428 (4)
H1B	1.3711	0.7228	0.4654	0.064*
O6	0.45576 (15)	0.39234 (7)	0.43781 (6)	0.0386 (4)
H6B	0.4259	0.4205	0.4668	0.046*
H6A	0.4103	0.3516	0.4199	0.046*
C13	0.8227 (2)	0.53500 (11)	0.45580 (10)	0.0308 (5)
C12	0.9046 (2)	0.60169 (12)	0.48543 (10)	0.0382 (5)
H12A	0.9347	0.5885	0.5293	0.046*
H12B	0.8321	0.6434	0.4882	0.046*
C11	1.0474 (2)	0.62845 (11)	0.44921 (10)	0.0390 (5)
H11A	1.0159	0.6505	0.4082	0.047*
H11B	1.1129	0.5853	0.4398	0.047*
C5	0.6405 (3)	0.42324 (12)	0.26241 (9)	0.0389 (5)
C6	0.5562 (3)	0.49213 (12)	0.28068 (10)	0.0380 (5)
C4	0.6598 (3)	0.39995 (15)	0.19871 (11)	0.0565 (7)
H4A	0.6182	0.4282	0.1649	0.068*
C10	0.4766 (3)	0.56851 (13)	0.36431 (11)	0.0539 (7)
H10A	0.4737	0.5787	0.4085	0.065*
C7	0.4842 (3)	0.53934 (15)	0.23605 (11)	0.0552 (7)
H7A	0.4881	0.5285	0.1919	0.066*
C1	0.7808 (3)	0.31957 (13)	0.29949 (11)	0.0504 (7)
H1A	0.8227	0.2921	0.3337	0.060*
C3	0.7403 (4)	0.33528 (16)	0.18596 (13)	0.0680 (9)
H3A	0.7531	0.3190	0.1434	0.082*
C9	0.4028 (3)	0.61769 (14)	0.32318 (12)	0.0667 (8)
H9A	0.3516	0.6601	0.3390	0.080*
C8	0.4071 (3)	0.60219 (16)	0.25800 (12)	0.0672 (8)
H8A	0.3579	0.6342	0.2287	0.081*
C2	0.8023 (3)	0.29448 (15)	0.23620 (14)	0.0652 (8)
H2A	0.8580	0.2506	0.2280	0.078*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Co1	0.03229 (17)	0.02827 (15)	0.02781 (14)	−0.00034 (13)	0.00030 (13)	−0.00079 (12)
P1	0.0257 (3)	0.0270 (3)	0.0385 (3)	−0.0013 (2)	−0.0008 (3)	0.0023 (2)
N1	0.0425 (13)	0.0365 (11)	0.0351 (10)	−0.0059 (9)	0.0035 (9)	−0.0090 (9)
N2	0.0425 (12)	0.0410 (11)	0.0302 (10)	0.0029 (9)	−0.0015 (8)	0.0016 (8)
O5	0.0475 (11)	0.0392 (9)	0.0362 (8)	−0.0118 (7)	0.0076 (7)	−0.0070 (7)
O4	0.0339 (10)	0.0326 (8)	0.0485 (9)	−0.0061 (7)	0.0075 (7)	−0.0067 (7)
O3	0.0304 (9)	0.0276 (8)	0.0708 (10)	0.0049 (6)	0.0001 (8)	0.0038 (7)
O2	0.0374 (9)	0.0327 (8)	0.0379 (8)	0.0052 (7)	−0.0020 (7)	0.0039 (7)
O1	0.0335 (10)	0.0529 (10)	0.0420 (9)	−0.0100 (7)	0.0022 (7)	0.0050 (8)
O6	0.0352 (9)	0.0345 (8)	0.0461 (9)	−0.0045 (7)	0.0035 (7)	−0.0085 (7)
C13	0.0313 (13)	0.0255 (11)	0.0355 (12)	0.0000 (10)	−0.0047 (10)	0.0036 (9)
C12	0.0304 (13)	0.0368 (12)	0.0476 (13)	−0.0056 (10)	0.0026 (11)	−0.0064 (10)
C11	0.0398 (15)	0.0394 (13)	0.0380 (12)	−0.0098 (10)	−0.0028 (10)	0.0009 (10)
C5	0.0422 (15)	0.0463 (13)	0.0281 (11)	−0.0168 (11)	−0.0001 (9)	−0.0049 (11)
C6	0.0378 (14)	0.0436 (13)	0.0326 (12)	−0.0115 (11)	−0.0038 (10)	0.0028 (10)
C4	0.081 (2)	0.0582 (16)	0.0306 (13)	−0.0185 (15)	0.0051 (13)	−0.0086 (12)
C10	0.0689 (19)	0.0539 (15)	0.0389 (13)	0.0184 (14)	−0.0041 (12)	0.0003 (12)
C7	0.0644 (19)	0.0675 (17)	0.0336 (13)	−0.0051 (15)	−0.0102 (12)	0.0079 (13)
C1	0.0569 (18)	0.0458 (15)	0.0485 (15)	−0.0023 (13)	0.0051 (12)	−0.0138 (12)
C3	0.094 (2)	0.070 (2)	0.0392 (15)	−0.0225 (18)	0.0194 (16)	−0.0194 (15)
C9	0.081 (2)	0.0611 (18)	0.0577 (18)	0.0288 (16)	−0.0069 (16)	0.0063 (14)
C8	0.078 (2)	0.0700 (19)	0.0533 (17)	0.0161 (17)	−0.0152 (16)	0.0185 (15)
C2	0.072 (2)	0.0529 (17)	0.071 (2)	−0.0049 (14)	0.0217 (16)	−0.0284 (15)

Geometric parameters (Å, º)

Co1—O2^i	2.0076 (13)	C12—H12A	0.9700
Co1—O6	2.0610 (14)	C12—H12B	0.9700
Co1—N1	2.1038 (16)	C11—H11A	0.9700
Co1—N2	2.1471 (17)	C11—H11B	0.9700
Co1—O4	2.1806 (14)	C5—C4	1.387 (3)
Co1—O5	2.2112 (15)	C5—C6	1.469 (3)
P1—O2	1.4948 (14)	C6—C7	1.390 (3)
P1—O3	1.5074 (14)	C4—C3	1.365 (3)
P1—O1	1.5690 (15)	C4—H4A	0.9300
P1—C11	1.791 (2)	C10—C9	1.373 (3)
N1—C5	1.348 (3)	C10—H10A	0.9300
N1—C1	1.346 (3)	C7—C8	1.373 (3)
N2—C10	1.336 (3)	C7—H7A	0.9300
N2—C6	1.345 (3)	C1—C2	1.391 (3)
O5—C13	1.251 (2)	C1—H1A	0.9300
O4—C13	1.269 (2)	C3—C2	1.372 (4)
O2—Co1^i	2.0076 (13)	C3—H3A	0.9300
O1—H1B	0.8200	C9—C8	1.372 (3)
O6—H6B	0.8200	C9—H9A	0.9300
O6—H6A	0.9000	C8—H8A	0.9300
C13—C12	1.506 (3)	C2—H2A	0.9300
C12—C11	1.517 (3)
O2^i—Co1—O6	93.64 (6)	C13—C12—H12B	108.5
O2^i—Co1—N1	91.64 (6)	C11—C12—H12B	108.5
O6—Co1—N1	107.10 (6)	H12A—C12—H12B	107.5
O2^i—Co1—N2	167.65 (6)	C12—C11—P1	112.65 (14)
O6—Co1—N2	87.65 (6)	C12—C11—H11A	109.1
N1—Co1—N2	76.26 (7)	P1—C11—H11A	109.1
O2^i—Co1—O4	100.73 (6)	C12—C11—H11B	109.1
O6—Co1—O4	94.36 (5)	P1—C11—H11B	109.1
N1—Co1—O4	154.52 (6)	H11A—C11—H11B	107.8
N2—Co1—O4	91.42 (6)	N1—C5—C4	121.0 (2)
O2^i—Co1—O5	94.97 (6)	N1—C5—C6	115.71 (17)
O6—Co1—O5	153.62 (5)	C4—C5—C6	123.3 (2)
N1—Co1—O5	97.53 (6)	N2—C6—C7	121.5 (2)
N2—Co1—O5	89.19 (6)	N2—C6—C5	115.10 (19)
O4—Co1—O5	59.54 (5)	C7—C6—C5	123.4 (2)
O2—P1—O3	113.57 (8)	C3—C4—C5	119.5 (2)
O2—P1—O1	111.85 (8)	C3—C4—H4A	120.2
O3—P1—O1	108.76 (8)	C5—C4—H4A	120.2
O2—P1—C11	109.46 (9)	N2—C10—C9	124.0 (2)
O3—P1—C11	109.55 (10)	N2—C10—H10A	118.0
O1—P1—C11	103.13 (9)	C9—C10—H10A	118.0
C5—N1—C1	119.60 (19)	C8—C7—C6	119.1 (2)
C5—N1—Co1	116.95 (14)	C8—C7—H7A	120.5
C1—N1—Co1	123.39 (16)	C6—C7—H7A	120.5
C10—N2—C6	117.89 (19)	N1—C1—C2	121.0 (2)
C10—N2—Co1	126.17 (14)	N1—C1—H1A	119.5
C6—N2—Co1	115.94 (14)	C2—C1—H1A	119.5
C13—O5—Co1	89.81 (12)	C4—C3—C2	119.7 (2)
C13—O4—Co1	90.73 (12)	C4—C3—H3A	120.2
P1—O2—Co1^i	147.36 (9)	C2—C3—H3A	120.2
P1—O1—H1B	109.5	C8—C9—C10	117.8 (2)
Co1—O6—H6B	109.5	C8—C9—H9A	121.1
Co1—O6—H6A	120.0	C10—C9—H9A	121.1
H6B—O6—H6A	130.5	C7—C8—C9	119.9 (2)
O5—C13—O4	119.84 (19)	C7—C8—H8A	120.1
O5—C13—C12	121.47 (19)	C9—C8—H8A	120.1
O4—C13—C12	118.69 (18)	C3—C2—C1	119.2 (3)
C13—C12—C11	115.28 (18)	C3—C2—H2A	120.4
C13—C12—H12A	108.5	C1—C2—H2A	120.4
C11—C12—H12A	108.5

Symmetry code: (i) −x+2, −y+1, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O6—H6B···O4^ii	0.82	1.93	2.7198 (19)	163
O1—H1B···O3^iii	0.82	1.72	2.533 (2)	169

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