supplementary materials


hy2495 scheme

Acta Cryst. (2012). E68, m74    [ doi:10.1107/S1600536811053700 ]

Bis[6-(1H-benzimidazol-2-yl-[kappa]N3)pyridine-2-carboxylato-[kappa]2N,O]cobalt(II) dihydrate

L. Han and D. Sun

Abstract top

In the title compound, [Co(C13H8N3O2)2]·2H2O, the CoII atom has a distorted octahedral environment defined by four N atoms and two O atoms from two 6-(1H-benzimidazol-2-yl)pyridine-2-carboxylate ligands. In the crystal, the complex molecules and uncoordinated water molecules are linked via N-H...O and O-H...O hydrogen bonds, forming a two-dimensional supramolecular structure parallel to (010). [pi]-[pi] interactions are present between the imidazole, pyridine and benzene rings [centroid-centroid distances = 3.528 (2), 3.592 (2), 3.680 (2) and 3.732 (3) Å].

Comment top

Molecular self-assembly of supramolecular architectures has received much attention during recent decades (Chun et al., 2005; Tranchemontagne et al., 2009). The structures and properties of such systems depend on the coordination and geometric preferences of both the central metal ions and bridging building blocks, as well as on the influence of weaker non-covalent interactions, such as hydrogen bonds and ππ stacking interactions. Multidentate ligands containing rich coordination sites (N and/or O donors) are often employed to produce polymeric networks with structural diversity owing to their various coordination modes (Eubank et al., 2011; Wang et al., 2009). Recently, we obtained the title mononuclear complex by the reaction of cobalt chloride with 6-(1H-benzimidazol-2-yl)pyridine-2-carboxylic acid using hydrothermal methods and its crystal structure is reported here.

In the title compound, the CoII atom has a distorted octahedral environment with four N atoms and two carboxylate O atoms from two 6-(1H-benzimidazol-2-yl)pyridine-2-carboxylate ligands (Fig. 1). The bond lengths and angles around the Co atom are normal. The complex molecules and uncoordinated water molecules are connected into a two-dimensional structure by extensive N—H···O and O—H···O hydrogen bonds (Fig. 2, Table 1). ππ interactions between the imidazole, pyridine and benzene rings are present [centroid–centroid distances = 3.528 (2), 3.592 (2), 3.680 (2) and 3.732 (3) Å].

Related literature top

For background to supramolecular architectures, see: Chun et al. (2005); Tranchemontagne et al. (2009). For related complexes with multidentate ligands, see: Eubank et al. (2011); Wang et al. (2009).

Experimental top

The synthesis was performed under hydrothermal conditions. A mixture of CoCl2.6H2O (0.2 mmol, 0.050 g), 6-(1H-benzimidazol-2-yl)pyridine-2-carboxylic acid (0.4 mmol, 0.098 g), NaOH (0.4 mmol, 0.016 g) and H2O (15 ml) in a 25 ml stainless steel reactor with a Teflon liner was heated from 293 to 433 K in 2 h and a constant temperature was maintained at 433 K for 72 h. After the mixture was cooled to 298 K, pink crystals of the title compound were recovered from the reaction.

Refinement top

H atoms on C and N atoms were positioned geometrically and refined as riding atoms, with C—H = 0.95 and N—H = 0.88 Å and with Uiso(H) = 1.2Ueq(C, N). H atoms of the water molecules were located from a difference Fourier map and refined as riding, with Uiso(H) = 1.5Ueq(O).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: XP in SHELXTL and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. View of the two-dimensional structure of the title compound built by hydrogen bonds (dashed lines).
Bis[6-(1H-benzimidazol-2-yl-κN3)pyridine-2-carboxylato- κ2N,O]cobalt(II) dihydrate top
Crystal data top
[Co(C13H8N3O2)2]·2H2OF(000) = 1172
Mr = 571.41Dx = 1.549 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 4827 reflections
a = 9.8602 (5) Åθ = 1.0–26.0°
b = 20.3681 (11) ŵ = 0.76 mm1
c = 13.1069 (7) ÅT = 185 K
β = 111.453 (1)°Block, pink
V = 2449.9 (2) Å30.24 × 0.15 × 0.12 mm
Z = 4
Data collection top
Bruker APEXII CCD
diffractometer
4827 independent reflections
Radiation source: fine-focus sealed tube3864 reflections with I > 2σ(I)
graphiteRint = 0.026
φ and ω scansθmax = 26.1°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
h = 1210
Tmin = 0.839, Tmax = 0.915k = 2325
13443 measured reflectionsl = 1616
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.049Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.150H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.0767P)2 + 2.8721P]
where P = (Fo2 + 2Fc2)/3
4827 reflections(Δ/σ)max = 0.001
352 parametersΔρmax = 0.96 e Å3
6 restraintsΔρmin = 0.59 e Å3
Crystal data top
[Co(C13H8N3O2)2]·2H2OV = 2449.9 (2) Å3
Mr = 571.41Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.8602 (5) ŵ = 0.76 mm1
b = 20.3681 (11) ÅT = 185 K
c = 13.1069 (7) Å0.24 × 0.15 × 0.12 mm
β = 111.453 (1)°
Data collection top
Bruker APEXII CCD
diffractometer
4827 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
3864 reflections with I > 2σ(I)
Tmin = 0.839, Tmax = 0.915Rint = 0.026
13443 measured reflectionsθmax = 26.1°
Refinement top
R[F2 > 2σ(F2)] = 0.049H-atom parameters constrained
wR(F2) = 0.150Δρmax = 0.96 e Å3
S = 1.06Δρmin = 0.59 e Å3
4827 reflectionsAbsolute structure: ?
352 parametersFlack parameter: ?
6 restraintsRogers parameter: ?
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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 (Å2) top
xyzUiso*/Ueq
C10.1555 (4)0.35179 (16)0.7579 (3)0.0386 (8)
C20.3187 (4)0.35664 (15)0.8211 (3)0.0321 (7)
C30.4130 (4)0.30476 (16)0.8634 (3)0.0384 (8)
H3A0.37790.26090.85580.046*
C40.5581 (4)0.31795 (16)0.9164 (3)0.0404 (8)
H4A0.62450.28290.94620.048*
C50.6094 (4)0.38247 (16)0.9270 (3)0.0356 (7)
H5A0.71000.39200.96310.043*
C60.5091 (3)0.43192 (15)0.8833 (2)0.0290 (6)
C70.5339 (3)0.50287 (14)0.8836 (2)0.0278 (6)
C80.6304 (3)0.60145 (15)0.9040 (3)0.0308 (7)
C90.7184 (4)0.65706 (16)0.9248 (3)0.0393 (8)
H9A0.82100.65450.96190.047*
C100.6487 (4)0.71598 (17)0.8885 (3)0.0420 (8)
H10A0.70520.75500.90020.050*
C110.4972 (4)0.72036 (16)0.8348 (3)0.0388 (8)
H11A0.45340.76210.81270.047*
C120.4113 (4)0.66545 (15)0.8138 (3)0.0337 (7)
H12A0.30870.66840.77710.040*
C130.4794 (3)0.60507 (14)0.8482 (3)0.0287 (6)
C140.0579 (4)0.57477 (19)0.8491 (4)0.0512 (10)
C150.0334 (4)0.60199 (19)0.7370 (3)0.0502 (10)
C160.0381 (5)0.6601 (2)0.6968 (4)0.0728 (16)
H16A0.08280.68480.73750.087*
C170.0424 (6)0.6812 (2)0.5950 (4)0.088 (2)
H17A0.08970.72140.56570.105*
C180.0215 (6)0.6445 (2)0.5353 (4)0.0763 (16)
H18A0.01880.65860.46550.092*
C190.0896 (4)0.58621 (18)0.5817 (3)0.0498 (10)
C200.1695 (4)0.54082 (17)0.5376 (3)0.0446 (9)
C210.2695 (5)0.49105 (19)0.4359 (3)0.0518 (10)
C220.3211 (6)0.4676 (3)0.3561 (4)0.0721 (14)
H22A0.29640.48870.28700.087*
C230.4077 (6)0.4137 (3)0.3816 (4)0.0718 (14)
H23A0.44280.39670.32830.086*
C240.4476 (5)0.3820 (2)0.4829 (4)0.0620 (11)
H24A0.51050.34500.49760.074*
C250.3962 (4)0.40391 (19)0.5622 (3)0.0486 (9)
H25A0.42160.38240.63100.058*
C260.3061 (4)0.45864 (17)0.5370 (3)0.0409 (8)
N10.3673 (3)0.41784 (12)0.8317 (2)0.0284 (5)
N20.4214 (3)0.54241 (12)0.8366 (2)0.0287 (6)
N30.6612 (3)0.53553 (13)0.9257 (2)0.0334 (6)
H30.74760.51820.96050.040*
N40.0940 (3)0.56671 (14)0.6808 (3)0.0421 (7)
N50.2413 (3)0.49147 (13)0.5994 (2)0.0363 (6)
N60.1837 (4)0.54260 (16)0.4400 (3)0.0599 (10)
H60.14470.57180.38790.072*
O10.0911 (2)0.40631 (11)0.7254 (2)0.0416 (6)
O20.0977 (3)0.29740 (13)0.7412 (3)0.0601 (8)
O1W0.1067 (4)0.5642 (2)1.1243 (4)0.1120 (16)
H1A0.03850.55791.15010.168*
H1B0.06790.57441.05590.168*
O2W0.2043 (5)0.3346 (3)0.7130 (6)0.179 (3)
H2A0.13890.30890.70080.268*
H2B0.16630.35330.78050.268*
O30.1308 (3)0.52097 (12)0.8735 (2)0.0477 (6)
O40.0139 (3)0.60542 (18)0.9118 (3)0.0748 (10)
Co10.22295 (4)0.49008 (2)0.75644 (4)0.03024 (16)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0422 (19)0.0317 (18)0.0419 (19)0.0054 (15)0.0154 (16)0.0014 (14)
C20.0403 (18)0.0260 (16)0.0333 (16)0.0007 (13)0.0174 (14)0.0001 (12)
C30.051 (2)0.0225 (16)0.0437 (19)0.0005 (14)0.0198 (16)0.0011 (13)
C40.048 (2)0.0294 (17)0.0440 (19)0.0130 (15)0.0165 (16)0.0032 (14)
C50.0355 (17)0.0300 (17)0.0404 (18)0.0058 (13)0.0128 (14)0.0023 (14)
C60.0319 (16)0.0270 (16)0.0303 (16)0.0031 (12)0.0140 (13)0.0006 (12)
C70.0294 (16)0.0278 (15)0.0289 (16)0.0022 (12)0.0140 (13)0.0021 (12)
C80.0311 (16)0.0282 (16)0.0358 (17)0.0018 (12)0.0155 (13)0.0029 (13)
C90.0330 (17)0.0362 (18)0.050 (2)0.0053 (14)0.0168 (16)0.0043 (15)
C100.044 (2)0.0309 (18)0.054 (2)0.0087 (15)0.0213 (17)0.0022 (15)
C110.0444 (19)0.0281 (17)0.045 (2)0.0003 (14)0.0172 (16)0.0027 (14)
C120.0337 (17)0.0282 (16)0.0384 (18)0.0024 (13)0.0122 (14)0.0026 (13)
C130.0317 (16)0.0262 (15)0.0330 (16)0.0021 (12)0.0176 (13)0.0032 (12)
C140.0300 (18)0.049 (2)0.073 (3)0.0037 (16)0.0162 (18)0.020 (2)
C150.0327 (19)0.046 (2)0.056 (2)0.0075 (16)0.0028 (16)0.0218 (18)
C160.058 (3)0.059 (3)0.068 (3)0.031 (2)0.016 (2)0.027 (2)
C170.095 (4)0.052 (3)0.068 (3)0.041 (3)0.027 (3)0.019 (2)
C180.098 (4)0.042 (2)0.049 (2)0.020 (2)0.020 (2)0.0059 (19)
C190.054 (2)0.0320 (18)0.043 (2)0.0024 (16)0.0060 (17)0.0085 (15)
C200.054 (2)0.0291 (18)0.0378 (19)0.0060 (16)0.0019 (16)0.0007 (14)
C210.069 (3)0.045 (2)0.042 (2)0.0137 (19)0.020 (2)0.0004 (17)
C220.110 (4)0.069 (3)0.049 (3)0.016 (3)0.044 (3)0.001 (2)
C230.093 (4)0.080 (3)0.063 (3)0.011 (3)0.054 (3)0.008 (3)
C240.070 (3)0.058 (3)0.072 (3)0.001 (2)0.042 (2)0.013 (2)
C250.058 (2)0.047 (2)0.051 (2)0.0019 (18)0.0310 (19)0.0018 (17)
C260.048 (2)0.0347 (18)0.044 (2)0.0115 (15)0.0210 (16)0.0069 (15)
N10.0339 (14)0.0228 (12)0.0306 (13)0.0019 (10)0.0143 (11)0.0002 (10)
N20.0276 (13)0.0253 (13)0.0342 (14)0.0013 (10)0.0124 (11)0.0012 (10)
N30.0255 (13)0.0306 (14)0.0428 (16)0.0031 (11)0.0109 (12)0.0021 (12)
N40.0343 (15)0.0312 (15)0.0485 (18)0.0017 (12)0.0004 (13)0.0095 (13)
N50.0421 (16)0.0287 (14)0.0378 (16)0.0047 (12)0.0141 (13)0.0024 (11)
N60.093 (3)0.0400 (19)0.0360 (18)0.0024 (18)0.0105 (18)0.0061 (14)
O10.0357 (13)0.0314 (12)0.0534 (15)0.0017 (10)0.0111 (11)0.0030 (11)
O20.0529 (17)0.0332 (14)0.082 (2)0.0138 (12)0.0099 (15)0.0031 (13)
O1W0.063 (2)0.130 (3)0.157 (4)0.002 (2)0.056 (2)0.065 (3)
O2W0.064 (3)0.174 (6)0.278 (8)0.023 (3)0.038 (4)0.033 (5)
O30.0461 (15)0.0418 (14)0.0653 (17)0.0004 (11)0.0321 (13)0.0061 (12)
O40.0603 (19)0.086 (2)0.082 (2)0.0234 (17)0.0312 (17)0.0224 (18)
Co10.0299 (3)0.0230 (2)0.0377 (3)0.00136 (16)0.01228 (19)0.00077 (17)
Geometric parameters (Å, °) top
C1—O21.228 (4)C16—H16A0.9500
C1—O11.273 (4)C17—C181.389 (8)
C1—C21.520 (5)C17—H17A0.9500
C2—N11.324 (4)C18—C191.390 (5)
C2—C31.383 (5)C18—H18A0.9500
C3—C41.369 (5)C19—N41.344 (5)
C3—H3A0.9500C19—C201.463 (6)
C4—C51.396 (5)C20—N51.322 (4)
C4—H4A0.9500C20—N61.337 (5)
C5—C61.381 (4)C21—N61.362 (6)
C5—H5A0.9500C21—C221.403 (6)
C6—N11.343 (4)C21—C261.404 (5)
C6—C71.466 (4)C22—C231.356 (7)
C7—N21.326 (4)C22—H22A0.9500
C7—N31.347 (4)C23—C241.398 (7)
C8—N31.383 (4)C23—H23A0.9500
C8—C91.392 (4)C24—C251.386 (5)
C8—C131.400 (4)C24—H24A0.9500
C9—C101.379 (5)C25—C261.388 (5)
C9—H9A0.9500C25—H25A0.9500
C10—C111.402 (5)C26—N51.381 (4)
C10—H10A0.9500N1—Co12.034 (2)
C11—C121.369 (5)N2—Co12.137 (3)
C11—H11A0.9500N3—H30.8800
C12—C131.395 (4)N4—Co12.028 (3)
C12—H12A0.9500N5—Co12.132 (3)
C13—N21.384 (4)N6—H60.8800
C14—O41.231 (5)O1—Co12.093 (2)
C14—O31.285 (5)O1W—H1A0.8661
C14—C151.506 (6)O1W—H1B0.8622
C15—N41.318 (5)O2W—H2A0.8899
C15—C161.380 (5)O2W—H2B0.9083
C16—C171.388 (8)O3—Co12.144 (3)
O2—C1—O1125.8 (3)N5—C20—C19118.9 (3)
O2—C1—C2119.0 (3)N6—C20—C19128.3 (3)
O1—C1—C2115.1 (3)N6—C21—C22133.8 (4)
N1—C2—C3120.9 (3)N6—C21—C26105.9 (3)
N1—C2—C1112.9 (3)C22—C21—C26120.3 (4)
C3—C2—C1126.3 (3)C23—C22—C21117.4 (4)
C4—C3—C2118.6 (3)C23—C22—H22A121.3
C4—C3—H3A120.7C21—C22—H22A121.3
C2—C3—H3A120.7C22—C23—C24122.7 (4)
C3—C4—C5120.5 (3)C22—C23—H23A118.6
C3—C4—H4A119.7C24—C23—H23A118.6
C5—C4—H4A119.7C25—C24—C23120.7 (4)
C6—C5—C4117.8 (3)C25—C24—H24A119.6
C6—C5—H5A121.1C23—C24—H24A119.6
C4—C5—H5A121.1C24—C25—C26117.2 (4)
N1—C6—C5120.6 (3)C24—C25—H25A121.4
N1—C6—C7110.8 (3)C26—C25—H25A121.4
C5—C6—C7128.6 (3)N5—C26—C25129.9 (3)
N2—C7—N3112.7 (3)N5—C26—C21108.5 (3)
N2—C7—C6119.1 (3)C25—C26—C21121.6 (4)
N3—C7—C6128.2 (3)C2—N1—C6121.6 (3)
N3—C8—C9132.5 (3)C2—N1—Co1117.9 (2)
N3—C8—C13105.7 (3)C6—N1—Co1120.3 (2)
C9—C8—C13121.8 (3)C7—N2—C13105.5 (3)
C10—C9—C8116.4 (3)C7—N2—Co1112.7 (2)
C10—C9—H9A121.8C13—N2—Co1141.4 (2)
C8—C9—H9A121.8C7—N3—C8107.1 (3)
C9—C10—C11122.3 (3)C7—N3—H3126.5
C9—C10—H10A118.9C8—N3—H3126.5
C11—C10—H10A118.9C15—N4—C19121.2 (3)
C12—C11—C10121.1 (3)C15—N4—Co1118.5 (3)
C12—C11—H11A119.5C19—N4—Co1119.5 (2)
C10—C11—H11A119.5C20—N5—C26105.4 (3)
C11—C12—C13117.8 (3)C20—N5—Co1112.7 (2)
C11—C12—H12A121.1C26—N5—Co1141.9 (2)
C13—C12—H12A121.1C20—N6—C21107.5 (3)
N2—C13—C12130.3 (3)C20—N6—H6126.2
N2—C13—C8109.1 (3)C21—N6—H6126.2
C12—C13—C8120.6 (3)C1—O1—Co1116.6 (2)
O4—C14—O3124.6 (4)H1A—O1W—H1B109.2
O4—C14—C15119.7 (4)H2A—O2W—H2B110.8
O3—C14—C15115.6 (3)C14—O3—Co1114.7 (3)
N4—C15—C16121.9 (4)N4—Co1—N1174.98 (11)
N4—C15—C14113.6 (3)N4—Co1—O1107.37 (10)
C16—C15—C14124.4 (4)N1—Co1—O177.25 (10)
C15—C16—C17117.6 (4)N4—Co1—N577.12 (12)
C15—C16—H16A121.2N1—Co1—N5100.74 (10)
C17—C16—H16A121.2O1—Co1—N595.12 (10)
C16—C17—C18121.0 (4)N4—Co1—N298.86 (10)
C16—C17—H17A119.5N1—Co1—N276.70 (10)
C18—C17—H17A119.5O1—Co1—N2153.43 (10)
C17—C18—C19117.4 (5)N5—Co1—N294.71 (10)
C17—C18—H18A121.3N4—Co1—O376.70 (12)
C19—C18—H18A121.3N1—Co1—O3105.66 (10)
N4—C19—C18121.0 (4)O1—Co1—O389.01 (10)
N4—C19—C20111.3 (3)N5—Co1—O3153.54 (11)
C18—C19—C20127.6 (4)N2—Co1—O393.05 (10)
N5—C20—N6112.7 (4)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N3—H3···O3i0.882.212.917 (4)137
N6—H6···O1ii0.882.302.971 (4)133
O1W—H1A···O3iii0.872.262.923 (4)134
O1W—H1B···O40.861.872.727 (6)170
O2W—H2A···O20.892.212.962 (6)142
O2W—H2B···O1Wiii0.912.052.867 (8)149
Symmetry codes: (i) −x+1, −y+1, −z+2; (ii) −x, −y+1, −z+1; (iii) −x, −y+1, −z+2.
Table 1
Hydrogen-bond geometry (Å, °)
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D—H···AD—HH···AD···AD—H···A
N3—H3···O3i0.882.212.917 (4)137
N6—H6···O1ii0.882.302.971 (4)133
O1W—H1A···O3iii0.872.262.923 (4)134
O1W—H1B···O40.861.872.727 (6)170
O2W—H2A···O20.892.212.962 (6)142
O2W—H2B···O1Wiii0.912.052.867 (8)149
Symmetry codes: (i) −x+1, −y+1, −z+2; (ii) −x, −y+1, −z+1; (iii) −x, −y+1, −z+2.
Acknowledgements top

The authors thank Jilin University for supporting this work.

references
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