Tetra­aqua­diazido­cobalt(II) 3,3′-dicarb­oxy­l­ato-1,1′-ethyl­enedipyridinium

The asymmetric unit of the title compound, [Co(N₃)₂(H₂O)₄]·C₁₄H₁₂N₂O₄, comprises half of the cobalt(II) complex mol­ecule and a half of the 3,3′-dicarboxyl­ato-1,1′-ethyl­enedipyridinium mol­ecule. The Co^II atom is located on an inversion centre and hence the complex mol­ecule adopts a centrosymmetric trans-octa­hedral geometry. The zwitterionic organic mol­ecule is also centrosymmetric with the centre of the C—C bond of the ethyl­ene moiety coinciding with an inversion centre. The adduct of metal complex and organic mol­ecule is associated into a three-dimenional network through O—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.024
• wR factor = 0.074
• Data-to-parameter ratio = 12.4

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT934_ALERT_3_B Number of (Iobs-Icalc)/SigmaW .gt. 10 Outliers .          1

Alert level C
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.42
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600         14
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600         17

Alert level G
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          9
PLAT154_ALERT_1_G The su's on the Cell Angles are Equal  (x 10000)        200 Deg.
PLAT794_ALERT_5_G Note: Tentative Bond Valency for Co1     .......       1.89

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

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

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S1. Comment

Hydrogen bonds play a key role in biological systems and materials, and they have been widely used as a putative supramolecular tool for engineering organic and metal-organic solids (Fabbiani et al., 2010; Salitros et al., 2010; Schultheis et al., 2010; Braga & Grepioni, 2000). In this paper, we report the structure of the title compound, (I), which contains a neutral metal complex molecule, [Co(N₃)₂(H₂O)₄], and a zwitterionic dicarboxylate, 1,2-bis(3-carboxylatopyridinium)ethane (Fig. 1). The metal complex molecule is centrosymmetric, with the octahedral-coordinated Co^II by two azide anions and four water molecules in a trans arrangement (Fig. 1, Table 1). Two opposite Co—O distances are longer than the Co—N and other Co—O ones, defining an axially elongated geometry. The zwitterionic molecule is also centrosymmetric (Fig.1 ). The inorganic complex molecules and the carboxylate groups are associated into a sheet through O—H···O hydrogen bonds involving the coordinated aqua ligands (O3 and O4) and the carboxylate oxygen atoms (O1 and O2) (Fig. 2, Table 2). The two O4 aqua ligands from symmetry related complex molecules and two O2 atoms from symmetry related organic molecules form a hydrogen-bonded ring which can be denoted by the graph set R₄²(8) (Bernstein et al., 1995; Etter, 1990). Similar hydrogen-bonded rings are formed by O1 and O3. The carboxylate group forms a R₂²(8) hydrogen-bonded ring with two aqua ligands from the same complex molecule. Besides, a large hydrogen-bonded ring [R₄⁴(16)] is formed by two carboxylate groups and four aqua ligands from two complex molecules. The organic ligands interlink the hydrogen-bonded sheets of the metal complexes into the three-dimensional structure (Fig. 3).

Related literature

For background to hydrogen bonds, see: Braga & Grepioni (2000); Fabbiani et al. (2010); Salitros et al. (2010); Schultheis et al. (2010). For the synthesis of the ligand, see: Loeb et al. (2006). For hydrogen-bond motifs, see: Bernstein et al. (1995); Etter (1990).

S2. Experimental

The zwitterionic ligand ([H₂L¹]Br₂) was synthesised from 1,2-dibromoethane and ethyl nicotinate according to the published procedure (Loeb et al., 2006). An aqueous solution (4 mL) of [H₂L¹]Br₂ (0.1 mmol) and NaN₃ (1 mmol) was added to a DMF solution (1.5 mL) of Co(ClO₄)₂.6H₂O (0.2 mmol) with stirring. The resulting solution was allowed to evaporate slowly at room temperature, yielding light-red block crystals of (I) in three days. Yield: 75%. Anal. calcd (found) (%) for CoC₁₄H₂₀N₈O₈: C, 34.79 (34.51); H, 4.39 (4.14); N, 22.87 (23.00). Main IR bands (KBr, ν/cm^-1): 3427m, 3097w, 2042 s, 1637 s, 1606 s, 1392m, 765m, 688m.

S3. Refinement

All hydrogen atoms attached to carbon atoms were placed at calculated positions and refined with the riding model using AFIX 43 and AFIX 23 instructions for aromatic C—H and secondary CH₂. The water hydrogen atoms were initially located from difference Fourier maps and refined isotropically with restraints on O—H distance (0.85 Å) and H—O—H angle, and U_iso(H) = 1.5U_eq(O). The 'rigid-bond' restraint was applied on the azide moiety (N2—N3—N4) using the SHELXL DELU instruction.

Computing details

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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 (Sheldrick, 2008).

Figures

	Fig. 1. The molecular structure of the title compound showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level. [Symmetry code: (i) -x, -y, 1 - z; (ii) 1 - x, -y, -z].
	Fig. 2. Two-dimensional layer structure connected through intermolecula O—H···O hydrogen bonds. [Symmetry code: (i) -x + 1, -y + 1, -z + 1; (ii) x, y - 1, z; (iii)-x, -y + 1, -z + 1].
	Fig. 3. Three dimensional structure connected by the organic ligands interlinking the hydrogen-bonded sheets.

Tetraaquadiazidocobalt(II) 3,3'-dicarboxylato-1,1'-ethylenedipyridinium

Crystal data

[Co(N3)2(H2O)4]·C14H12N2O4	Z = 1
Mr = 487.31	F(000) = 251
Triclinic, P1	Dx = 1.656 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.4309 (6) Å	Cell parameters from 15377 reflections
b = 7.7507 (7) Å	θ = 3.4–27.5°
c = 8.5582 (7) Å	µ = 0.94 mm^−1
α = 95.463 (2)°	T = 296 K
β = 90.586 (2)°	Block, red
γ = 95.011 (2)°	0.25 × 0.20 × 0.15 mm
V = 488.71 (7) Å^3

Data collection

Bruker APEXII CCD area-detector diffractometer	1907 independent reflections
Radiation source: fine-focus sealed tube	1889 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.015
phi and ω scans	θmax = 26.1°, θmin = 2.4°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −9→9
Tmin = 0.799, Tmax = 0.872	k = −9→8
6091 measured reflections	l = −10→10

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)] = 0.024	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.074	H atoms treated by a mixture of independent and constrained refinement
S = 1.12	w = 1/[σ^2(Fo^2) + (0.0411P)^2 + 0.2239P] where P = (Fo^2 + 2Fc^2)/3
1907 reflections	(Δ/σ)max < 0.001
154 parameters	Δρmax = 0.28 e Å^−3
9 restraints	Δρmin = −0.28 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	0.0000	0.0000	0.5000	0.02282 (12)
C1	0.3729 (2)	0.5896 (2)	0.3420 (2)	0.0283 (3)
C2	0.5025 (2)	0.4708 (2)	0.26023 (19)	0.0258 (3)
C3	0.6822 (2)	0.5278 (2)	0.2423 (2)	0.0335 (4)
H3A	0.7234	0.6424	0.2751	0.040*
C4	0.4437 (2)	0.3011 (2)	0.20731 (19)	0.0255 (3)
H4A	0.3228	0.2613	0.2153	0.031*
C5	0.8009 (2)	0.4148 (3)	0.1756 (3)	0.0392 (4)
H5A	0.9215	0.4530	0.1625	0.047*
C6	0.7382 (2)	0.2466 (2)	0.1293 (2)	0.0339 (4)
H6A	0.8173	0.1685	0.0875	0.041*
C7	0.5003 (2)	0.0111 (2)	0.08913 (19)	0.0286 (3)
H7A	0.3795	−0.0177	0.1265	0.034*
H7B	0.5803	−0.0667	0.1303	0.034*
N1	0.56206 (18)	0.19334 (17)	0.14405 (16)	0.0257 (3)
N2	0.0817 (2)	−0.0222 (2)	0.26583 (18)	0.0399 (4)
N3	−0.0146 (2)	−0.1006 (2)	0.16704 (17)	0.0320 (3)
N4	−0.1073 (3)	−0.1740 (2)	0.0672 (2)	0.0461 (4)
O1	0.43867 (18)	0.73681 (16)	0.39597 (19)	0.0435 (4)
O2	0.21281 (17)	0.52889 (16)	0.35044 (18)	0.0405 (3)
O3	0.27781 (16)	−0.00456 (16)	0.56790 (15)	0.0319 (3)
H3B	0.347 (3)	0.086 (2)	0.569 (3)	0.048*
H3C	0.321 (3)	−0.082 (2)	0.508 (3)	0.048*
O4	0.02796 (18)	0.26995 (16)	0.50991 (18)	0.0379 (3)
H4B	0.090 (3)	0.323 (3)	0.449 (3)	0.057*
H4C	−0.053 (3)	0.334 (3)	0.547 (3)	0.057*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Co1	0.02008 (17)	0.02004 (17)	0.02747 (17)	−0.00003 (11)	0.00302 (11)	−0.00082 (11)
C1	0.0273 (8)	0.0202 (7)	0.0363 (8)	0.0007 (6)	0.0062 (7)	−0.0031 (6)
C2	0.0247 (8)	0.0210 (7)	0.0305 (8)	0.0009 (6)	0.0035 (6)	−0.0024 (6)
C3	0.0282 (9)	0.0247 (8)	0.0445 (10)	−0.0047 (7)	0.0040 (7)	−0.0067 (7)
C4	0.0220 (7)	0.0230 (8)	0.0301 (8)	0.0002 (6)	0.0040 (6)	−0.0026 (6)
C5	0.0231 (8)	0.0348 (9)	0.0565 (12)	−0.0035 (7)	0.0081 (8)	−0.0077 (8)
C6	0.0247 (8)	0.0311 (9)	0.0447 (10)	0.0045 (7)	0.0068 (7)	−0.0056 (7)
C7	0.0331 (8)	0.0179 (7)	0.0336 (9)	0.0000 (6)	0.0054 (7)	−0.0030 (6)
N1	0.0256 (7)	0.0203 (6)	0.0297 (7)	0.0006 (5)	0.0035 (5)	−0.0043 (5)
N2	0.0335 (8)	0.0555 (10)	0.0297 (8)	−0.0006 (7)	0.0064 (6)	0.0028 (7)
N3	0.0314 (8)	0.0343 (8)	0.0318 (8)	0.0069 (6)	0.0117 (7)	0.0059 (6)
N4	0.0475 (10)	0.0485 (10)	0.0398 (9)	−0.0053 (8)	0.0032 (8)	−0.0011 (8)
O1	0.0330 (7)	0.0226 (6)	0.0701 (10)	−0.0026 (5)	0.0105 (6)	−0.0159 (6)
O2	0.0282 (6)	0.0241 (6)	0.0665 (9)	−0.0017 (5)	0.0160 (6)	−0.0082 (6)
O3	0.0230 (6)	0.0274 (6)	0.0434 (7)	0.0016 (5)	0.0014 (5)	−0.0067 (5)
O4	0.0356 (7)	0.0210 (6)	0.0575 (8)	0.0026 (5)	0.0178 (6)	0.0028 (5)

Geometric parameters (Å, º)

Co1—O4	2.0780 (12)	C5—C6	1.366 (3)
Co1—O4^i	2.0780 (12)	C5—H5A	0.9300
Co1—N2	2.0958 (15)	C6—N1	1.349 (2)
Co1—N2^i	2.0958 (15)	C6—H6A	0.9300
Co1—O3^i	2.1431 (12)	C7—N1	1.478 (2)
Co1—O3	2.1431 (12)	C7—C7^ii	1.519 (3)
C1—O1	1.245 (2)	C7—H7A	0.9700
C1—O2	1.246 (2)	C7—H7B	0.9700
C1—C2	1.521 (2)	N2—N3	1.188 (2)
C2—C4	1.381 (2)	N3—N4	1.164 (2)
C2—C3	1.384 (2)	O3—H3B	0.836 (15)
C3—C5	1.386 (3)	O3—H3C	0.839 (15)
C3—H3A	0.9300	O4—H4B	0.813 (16)
C4—N1	1.348 (2)	O4—H4C	0.856 (16)
C4—H4A	0.9300
O4—Co1—O4^i	180.0	N1—C4—H4A	120.1
O4—Co1—N2	91.41 (6)	C2—C4—H4A	120.1
O4^i—Co1—N2	88.59 (6)	C6—C5—C3	119.02 (16)
O4—Co1—N2^i	88.59 (6)	C6—C5—H5A	120.5
O4^i—Co1—N2^i	91.41 (6)	C3—C5—H5A	120.5
N2—Co1—N2^i	180.0	N1—C6—C5	120.23 (16)
O4—Co1—O3^i	88.83 (5)	N1—C6—H6A	119.9
O4^i—Co1—O3^i	91.17 (5)	C5—C6—H6A	119.9
N2—Co1—O3^i	92.17 (6)	N1—C7—C7^ii	109.09 (16)
N2^i—Co1—O3^i	87.83 (6)	N1—C7—H7A	109.9
O4—Co1—O3	91.17 (5)	C7^ii—C7—H7A	109.9
O4^i—Co1—O3	88.83 (5)	N1—C7—H7B	109.9
N2—Co1—O3	87.83 (6)	C7^ii—C7—H7B	109.9
N2^i—Co1—O3	92.17 (6)	H7A—C7—H7B	108.3
O3^i—Co1—O3	180.0	C4—N1—C6	121.82 (14)
O1—C1—O2	126.73 (15)	C4—N1—C7	120.05 (13)
O1—C1—C2	116.50 (14)	C6—N1—C7	118.13 (14)
O2—C1—C2	116.75 (14)	N3—N2—Co1	120.05 (12)
C4—C2—C3	118.77 (14)	N4—N3—N2	178.01 (19)
C4—C2—C1	120.22 (14)	Co1—O3—H3B	119.4 (17)
C3—C2—C1	120.97 (14)	Co1—O3—H3C	107.1 (17)
C2—C3—C5	120.26 (16)	H3B—O3—H3C	108.0 (19)
C2—C3—H3A	119.9	Co1—O4—H4B	122.9 (18)
C5—C3—H3A	119.9	Co1—O4—H4C	123.1 (17)
N1—C4—C2	119.85 (14)	H4B—O4—H4C	109 (2)
O1—C1—C2—C4	175.22 (17)	C2—C4—N1—C6	−0.5 (3)
O2—C1—C2—C4	−3.6 (2)	C2—C4—N1—C7	179.21 (14)
O1—C1—C2—C3	−2.5 (3)	C5—C6—N1—C4	−1.6 (3)
O2—C1—C2—C3	178.67 (17)	C5—C6—N1—C7	178.70 (17)
C4—C2—C3—C5	−1.5 (3)	C7^ii—C7—N1—C4	108.4 (2)
C1—C2—C3—C5	176.28 (18)	C7^ii—C7—N1—C6	−71.9 (2)
C3—C2—C4—N1	2.0 (2)	O4—Co1—N2—N3	−122.40 (16)
C1—C2—C4—N1	−175.75 (15)	O4^i—Co1—N2—N3	57.60 (16)
C2—C3—C5—C6	−0.6 (3)	O3^i—Co1—N2—N3	−33.51 (16)
C3—C5—C6—N1	2.1 (3)	O3—Co1—N2—N3	146.49 (16)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3B···O1^iii	0.84 (2)	2.01 (2)	2.8180 (18)	163 (2)
O3—H3C···O1^iv	0.84 (2)	1.91 (2)	2.7395 (17)	172 (2)
O4—H4C···O2^v	0.86 (2)	1.84 (2)	2.6901 (18)	173 (3)
O4—H4B···O2	0.81 (2)	2.03 (2)	2.8028 (18)	159 (2)

Symmetry codes: (iii) −x+1, −y+1, −z+1; (iv) x, y−1, z; (v) −x, −y+1, −z+1.