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Acta Cryst. (2008). E64, m319    [ doi:10.1107/S160053680706878X ]

Diacetatobis[1,3-bis(benzimidazol-2-yl)benzene]zinc(II) dihydrate

F.-Y. Meng, L. Teng, X. M. Chen, B. L. Zhao and P. Jiao

Abstract top

In the title complex, [Zn(CH3COO)2(C20H14N4)2]·2H2O, the ZnII atom, which lies on a crystallographic twofold axis, is coordinated by two O atoms of two acetate ligands and two N atoms from two 1,3-bis(benzimidazol-2-yl)benzene ligands in a distorted tetrahedral geometry. The complex molecules and solvent water molecules are connected via O-H...N, O-H...O and N-H...O hydrogen bonds, forming a three-dimensional network.

Comment top

Benzimidazolyl derivatives and their transition metal complexes have been extensively investigated (Shivakumaraiah et al., 2003). In previous works zinc terephthalate and zinc succinate adducts of 1,3-bis(benzimidazol-2-ylmethyl)benzene have been reported (Meng et al., 2007; Meng et al., 2007). The present work reports the crystal structure of [Zn(ac)2(L)2].2H2O, (I), where L is 1,3-bis(benzimidazol-2-ylmethyl)benzene and ac is the acetate ion, which assumes a similar geometry to previously reported complexes in the literature (Meng et al., 2007). (shown in scheme I). The crystal structure of (I) consists of the mononuclear zinc(II) complex and solvato water molecules (Fig. 1). The Zn atom is four-coordinate with two N atoms and two O atoms from the 1,3-bis(benzimidazol-2- ylmethyl)benzene and the acetate ligands, respectively. (Zn—O: 2.0145 (9) Å, Zn—N: 2.0477 (10) Å, coordination angle range: 101.39 (4)- 127.50 (5) °.). The complex and solvent water molecules are connected via O—H···N, O—H···O and N—H···O hydrogen bonds to form a three-dimensional network (Table 1).

Related literature top

For related literature, see: Meng et al. (2007); Chawla et al. (1997); Shivakumaraiah et al. (2003).

Experimental top

The N-heterocycle was prepared according to reported procedure (Chawla & Gill,1997). Zinc nitrate hexahydrate (0.074 g, 0.25 mmol), 1,3-bis(benzimidazolyl-2-ylmethyl)benzene (0.15 g, 0.5 mmol), acetic acid (2 ml) and water (15 ml) were placed in a 23 ml Teflon-lined stainless steel Parr bomb. The bomb was heated at 433 K for 5 days and cooled to room temperature at 5 K h-1.Colorless block crystals were obtained in 15% yield.

Refinement top

H atoms attached to oxygen and nitrogen were located in the Fourier maps, and refined with restrained N—H = 0.87 Å, O—H = 0.84 Å distances and free isotropic displacement factots. C—H's were placed at geometrically idealized positions with C—H = 0.95 Å (aromatic), 0.98 Å (methyl) and Uiso(H) = 1.2(aromatic), 1.5(methyl)Ueq(C).

Computing details top

Data collection: RAPID-AUTO (Rigaku 2004); cell refinement: RAPID-AUTO (Rigaku 2004); data reduction: RAPID-AUTO (Rigaku 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2000); software used to prepare material for publication: SHELXTL (Sheldrick, 2000).

Figures top
[Figure 1] Fig. 1. Molecular unit of (I) showing the coordination geometry of zinc. Displacement ellipsoids drawn at a 50% probability level. The independent part of the molecule drawn with heavy bonds; the (overlapping) symmetry related one, with light bonds. Only H atoms invovled in H-bonding (in dashed lines) have been included.[Symmery code (i): 1 - x, y, 1/2 - z].
Diacetatobis[1,3-bis(benzimidazol-2-yl)benzene]zinc(II) dihydrate top
Crystal data top
[Zn(C2H3O2)2(C20H14N4)2]·2H2OF(000) = 1744
Mr = 840.19Dx = 1.427 Mg m−3
Orthorhombic, PbcnMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2n 2abCell parameters from 29371 reflections
a = 14.1429 (3) Åθ = 3.1–27.5°
b = 16.7005 (4) ŵ = 0.69 mm−1
c = 16.5588 (3) ÅT = 153 K
V = 3911.08 (13) Å3Block, colourless
Z = 40.42 × 0.29 × 0.26 mm
Data collection top
Rigaku R-axis SPIDER
diffractometer		4483 independent reflections
Radiation source: Rotating Anode4032 reflections with I > 2σ(I)
graphiteRint = 0.022
ω scansθmax = 27.5°, θmin = 3.1°
Absorption correction: multi-scan
(Higashi, 1995)		h = −18→18
Tmin = 0.761, Tmax = 0.841k = −21→21
36097 measured reflectionsl = −21→20
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.027H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.080 w = 1/[σ2(Fo2) + (0.0456P)2 + 1.3144P]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max = 0.001
4483 reflectionsΔρmax = 0.35 e Å−3
285 parametersΔρmin = −0.35 e Å−3
4 restraintsExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0019 (3)
Crystal data top
[Zn(C2H3O2)2(C20H14N4)2]·2H2OV = 3911.08 (13) Å3
Mr = 840.19Z = 4
Orthorhombic, PbcnMo Kα radiation
a = 14.1429 (3) ŵ = 0.69 mm−1
b = 16.7005 (4) ÅT = 153 K
c = 16.5588 (3) Å0.42 × 0.29 × 0.26 mm
Data collection top
Rigaku R-axis SPIDER
diffractometer		4032 reflections with I > 2σ(I)
Absorption correction: multi-scan
(Higashi, 1995)		Rint = 0.022
Tmin = 0.761, Tmax = 0.841θmax = 27.5°
36097 measured reflectionsStandard reflections: 0
4483 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.027H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.080Δρmax = 0.35 e Å−3
S = 1.06Δρmin = −0.35 e Å−3
4483 reflectionsAbsolute structure: ?
285 parametersFlack parameter: ?
4 restraintsRogers parameter: ?
Special details top

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 (Å2) top
xyzUiso*/Ueq
Zn0.50000.200846 (12)0.25000.02036 (8)
O10.43810 (7)0.14750 (5)0.15455 (5)0.0247 (2)
O20.38164 (9)0.08183 (6)0.25947 (6)0.0346 (2)
N10.59696 (7)0.27314 (6)0.19415 (6)0.0199 (2)
N20.65402 (8)0.38807 (6)0.14616 (6)0.0229 (2)
N30.58881 (8)0.23678 (7)0.50153 (7)0.0239 (2)
N40.62077 (8)0.34087 (7)0.58182 (7)0.0270 (2)
C10.62241 (8)0.26200 (7)0.11345 (7)0.0200 (2)
C20.62085 (9)0.19356 (8)0.06492 (8)0.0243 (3)
H20.59990.14340.08530.029*
C30.65122 (10)0.20211 (8)−0.01423 (8)0.0287 (3)
H30.65090.1567−0.04880.034*
C40.68243 (10)0.27583 (9)−0.04472 (8)0.0309 (3)
H40.70130.2794−0.09970.037*
C50.68638 (10)0.34315 (8)0.00321 (8)0.0277 (3)
H50.70830.3930−0.01720.033*
C60.65670 (9)0.33473 (7)0.08296 (7)0.0220 (2)
C70.61950 (8)0.34911 (7)0.21111 (7)0.0203 (2)
C80.61087 (8)0.38614 (7)0.29088 (7)0.0214 (2)
C90.59900 (9)0.46915 (8)0.30015 (8)0.0252 (3)
H90.59770.50310.25410.030*
C100.58919 (10)0.50126 (8)0.37704 (9)0.0284 (3)
H100.58070.55730.38330.034*
C110.59159 (9)0.45248 (8)0.44476 (8)0.0264 (3)
H110.58520.47520.49710.032*
C120.60338 (9)0.36969 (7)0.43607 (8)0.0223 (2)
C130.60420 (9)0.31727 (8)0.50712 (8)0.0229 (2)
C140.61670 (10)0.27139 (8)0.62767 (8)0.0272 (3)
C150.63182 (12)0.26000 (10)0.71047 (9)0.0375 (3)
H150.64620.30380.74500.045*
C160.62511 (14)0.18299 (11)0.74009 (9)0.0405 (4)
H160.63520.17380.79600.049*
C170.60381 (11)0.11817 (9)0.69005 (9)0.0359 (3)
H170.59930.06610.71280.043*
C180.58912 (10)0.12804 (8)0.60805 (9)0.0305 (3)
H180.57500.08400.57380.037*
C190.59617 (9)0.20575 (8)0.57840 (8)0.0248 (3)
C200.61400 (9)0.33772 (7)0.35896 (8)0.0219 (3)
H200.62360.28170.35280.026*
C210.39227 (9)0.08843 (7)0.18557 (8)0.0236 (3)
C220.35683 (12)0.02507 (9)0.12828 (9)0.0359 (3)
H22A0.4009−0.02020.12800.043*
H22B0.35220.04750.07380.043*
H22C0.29430.00670.14580.043*
H2N0.6812 (12)0.4349 (7)0.1461 (11)0.043 (5)*
H3N0.5746 (13)0.2099 (9)0.4590 (8)0.038 (5)*
O30.73576 (9)0.53271 (6)0.13461 (7)0.0396 (3)
H3AO0.7035 (13)0.5725 (9)0.1205 (12)0.055 (6)*
H3BO0.7795 (12)0.5466 (12)0.1658 (11)0.057 (6)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Zn0.02511 (12)0.01605 (12)0.01992 (12)0.0000.00432 (7)0.000
O10.0304 (5)0.0176 (4)0.0262 (5)−0.0038 (3)0.0034 (4)0.0008 (3)
O20.0477 (6)0.0271 (5)0.0291 (5)−0.0057 (5)0.0114 (4)0.0010 (4)
N10.0221 (5)0.0175 (5)0.0201 (5)−0.0003 (4)0.0027 (4)−0.0001 (4)
N20.0252 (5)0.0195 (5)0.0239 (5)−0.0036 (4)−0.0017 (4)0.0035 (4)
N30.0279 (6)0.0229 (5)0.0208 (5)−0.0006 (4)−0.0004 (4)−0.0012 (4)
N40.0323 (6)0.0267 (6)0.0219 (5)−0.0011 (4)−0.0026 (4)−0.0012 (4)
C10.0184 (5)0.0218 (6)0.0196 (6)0.0018 (4)0.0014 (4)0.0022 (5)
C20.0241 (6)0.0228 (6)0.0260 (6)0.0022 (5)0.0035 (5)−0.0003 (5)
C30.0284 (7)0.0333 (7)0.0243 (6)0.0048 (5)0.0026 (5)−0.0045 (5)
C40.0289 (7)0.0421 (8)0.0216 (6)0.0030 (6)0.0033 (5)0.0035 (6)
C50.0276 (6)0.0318 (7)0.0237 (6)−0.0022 (5)0.0004 (5)0.0090 (5)
C60.0205 (6)0.0229 (6)0.0226 (6)−0.0001 (5)−0.0016 (5)0.0030 (5)
C70.0200 (5)0.0182 (5)0.0227 (6)0.0001 (4)−0.0008 (5)0.0020 (5)
C80.0205 (6)0.0202 (6)0.0236 (6)−0.0015 (4)−0.0018 (5)−0.0015 (5)
C90.0278 (6)0.0191 (6)0.0287 (6)−0.0012 (5)−0.0045 (5)0.0013 (5)
C100.0335 (7)0.0187 (6)0.0332 (7)0.0014 (5)−0.0055 (6)−0.0043 (5)
C110.0288 (6)0.0240 (6)0.0263 (6)0.0019 (5)−0.0022 (5)−0.0063 (5)
C120.0211 (6)0.0219 (6)0.0239 (6)−0.0001 (4)−0.0022 (5)−0.0009 (5)
C130.0219 (6)0.0233 (6)0.0233 (6)0.0009 (5)−0.0011 (5)−0.0023 (5)
C140.0276 (7)0.0285 (7)0.0255 (6)−0.0005 (5)−0.0012 (5)0.0005 (5)
C150.0499 (9)0.0384 (8)0.0241 (7)−0.0034 (7)−0.0054 (6)−0.0009 (6)
C160.0507 (10)0.0463 (9)0.0246 (7)0.0003 (8)−0.0030 (6)0.0074 (6)
C170.0404 (8)0.0334 (7)0.0338 (7)0.0027 (6)0.0038 (6)0.0093 (6)
C180.0341 (7)0.0260 (6)0.0313 (7)0.0015 (5)0.0036 (6)0.0016 (6)
C190.0224 (6)0.0287 (6)0.0234 (6)0.0013 (5)0.0013 (5)0.0016 (5)
C200.0229 (6)0.0182 (6)0.0246 (6)−0.0002 (4)−0.0018 (5)−0.0016 (5)
C210.0241 (6)0.0177 (6)0.0290 (6)0.0003 (4)0.0019 (5)0.0022 (5)
C220.0432 (9)0.0275 (7)0.0370 (8)−0.0092 (6)−0.0095 (6)0.0003 (6)
O30.0458 (7)0.0217 (5)0.0511 (7)−0.0099 (5)−0.0215 (5)0.0115 (5)
Geometric parameters (Å, °) top
Zn—O12.0145 (9)C8—C201.3880 (17)
Zn—O1i2.0145 (9)C8—C91.4047 (17)
Zn—N12.0477 (10)C9—C101.3886 (19)
Zn—N1i2.0477 (10)C9—H90.9500
O1—C211.2873 (15)C10—C111.386 (2)
O2—C211.2378 (16)C10—H100.9500
N1—C71.3380 (16)C11—C121.4001 (17)
N1—C11.3964 (15)C11—H110.9500
N2—C71.3485 (16)C12—C201.3923 (17)
N2—C61.3748 (16)C12—C131.4664 (18)
N2—H2N0.871 (9)C14—C191.3970 (19)
N3—C131.3649 (16)C14—C151.4006 (19)
N3—C191.3782 (17)C15—C161.380 (2)
N3—H3N0.858 (9)C15—H150.9500
N4—C131.3193 (17)C16—C171.396 (2)
N4—C141.3878 (17)C16—H160.9500
C1—C21.3974 (17)C17—C181.384 (2)
C1—C61.4020 (17)C17—H170.9500
C2—C31.3867 (19)C18—C191.3912 (19)
C2—H20.9500C18—H180.9500
C3—C41.402 (2)C20—H200.9500
C3—H30.9500C21—C221.5069 (18)
C4—C51.377 (2)C22—H22A0.9800
C4—H40.9500C22—H22B0.9800
C5—C61.3928 (18)C22—H22C0.9800
C5—H50.9500O3—H3AO0.839 (9)
C7—C81.4636 (17)O3—H3BO0.839 (9)
O1—Zn—O1i127.50 (5)C11—C10—C9120.81 (12)
O1—Zn—N1101.39 (4)C11—C10—H10119.6
O1i—Zn—N1108.91 (4)C9—C10—H10119.6
O1—Zn—N1i108.91 (4)C10—C11—C12120.01 (12)
O1i—Zn—N1i101.39 (4)C10—C11—H11120.0
N1—Zn—N1i107.74 (6)C12—C11—H11120.0
C21—O1—Zn104.16 (8)C20—C12—C11119.07 (12)
C7—N1—C1105.41 (10)C20—C12—C13120.39 (11)
C7—N1—Zn128.60 (8)C11—C12—C13120.54 (12)
C1—N1—Zn121.75 (8)N4—C13—N3112.71 (12)
C7—N2—C6107.73 (10)N4—C13—C12125.12 (12)
C7—N2—H2N126.4 (12)N3—C13—C12122.16 (11)
C6—N2—H2N124.6 (12)N4—C14—C19110.20 (12)
C13—N3—C19107.19 (11)N4—C14—C15130.00 (13)
C13—N3—H3N127.4 (12)C19—C14—C15119.79 (13)
C19—N3—H3N125.3 (12)C16—C15—C14117.66 (14)
C13—N4—C14104.82 (11)C16—C15—H15121.2
N1—C1—C2130.94 (11)C14—C15—H15121.2
N1—C1—C6108.57 (11)C15—C16—C17121.78 (14)
C2—C1—C6120.46 (11)C15—C16—H16119.1
C3—C2—C1117.04 (12)C17—C16—H16119.1
C3—C2—H2121.5C18—C17—C16121.50 (14)
C1—C2—H2121.5C18—C17—H17119.3
C2—C3—C4121.89 (13)C16—C17—H17119.3
C2—C3—H3119.1C17—C18—C19116.54 (14)
C4—C3—H3119.1C17—C18—H18121.7
C5—C4—C3121.48 (12)C19—C18—H18121.7
C5—C4—H4119.3N3—C19—C18132.16 (13)
C3—C4—H4119.3N3—C19—C14105.07 (11)
C4—C5—C6116.86 (12)C18—C19—C14122.74 (13)
C4—C5—H5121.6C8—C20—C12121.19 (11)
C6—C5—H5121.6C8—C20—H20119.4
N2—C6—C5131.66 (12)C12—C20—H20119.4
N2—C6—C1106.12 (11)O2—C21—O1121.59 (12)
C5—C6—C1122.22 (12)O2—C21—C22121.30 (12)
N1—C7—N2112.11 (11)O1—C21—C22117.02 (12)
N1—C7—C8124.76 (11)C21—C22—H22A109.5
N2—C7—C8123.11 (11)C21—C22—H22B109.5
C20—C8—C9119.35 (11)H22A—C22—H22B109.5
C20—C8—C7118.95 (11)C21—C22—H22C109.5
C9—C8—C7121.70 (12)H22A—C22—H22C109.5
C10—C9—C8119.55 (12)H22B—C22—H22C109.5
C10—C9—H9120.2H3AO—O3—H3BO110.7 (19)
C8—C9—H9120.2
O1i—Zn—O1—C2140.82 (7)C20—C8—C9—C10−0.95 (19)
N1—Zn—O1—C21165.66 (8)C7—C8—C9—C10178.68 (12)
N1i—Zn—O1—C21−80.92 (8)C8—C9—C10—C110.4 (2)
O1—Zn—N1—C7137.44 (10)C9—C10—C11—C12−0.4 (2)
O1i—Zn—N1—C7−86.05 (11)C10—C11—C12—C200.97 (19)
N1i—Zn—N1—C723.14 (9)C10—C11—C12—C13−178.81 (12)
O1—Zn—N1—C1−15.92 (10)C14—N4—C13—N30.51 (15)
O1i—Zn—N1—C1120.59 (9)C14—N4—C13—C12−178.52 (12)
N1i—Zn—N1—C1−130.22 (10)C19—N3—C13—N4−0.16 (15)
C7—N1—C1—C2175.43 (13)C19—N3—C13—C12178.90 (11)
Zn—N1—C1—C2−25.88 (18)C20—C12—C13—N4160.33 (13)
C7—N1—C1—C6−2.48 (13)C11—C12—C13—N4−19.9 (2)
Zn—N1—C1—C6156.20 (8)C20—C12—C13—N3−18.61 (18)
N1—C1—C2—C3−179.94 (13)C11—C12—C13—N3161.17 (12)
C6—C1—C2—C3−2.24 (19)C13—N4—C14—C19−0.68 (15)
C1—C2—C3—C40.1 (2)C13—N4—C14—C15177.69 (15)
C2—C3—C4—C51.5 (2)N4—C14—C15—C16−178.56 (15)
C3—C4—C5—C6−0.9 (2)C19—C14—C15—C16−0.3 (2)
C7—N2—C6—C5−179.54 (13)C14—C15—C16—C17−0.2 (3)
C7—N2—C6—C1−0.20 (13)C15—C16—C17—C180.5 (3)
C4—C5—C6—N2177.96 (13)C16—C17—C18—C19−0.3 (2)
C4—C5—C6—C1−1.29 (19)C13—N3—C19—C18−178.53 (14)
N1—C1—C6—N21.67 (13)C13—N3—C19—C14−0.26 (14)
C2—C1—C6—N2−176.50 (11)C17—C18—C19—N3177.85 (14)
N1—C1—C6—C5−178.92 (12)C17—C18—C19—C14−0.2 (2)
C2—C1—C6—C52.91 (19)N4—C14—C19—N30.59 (15)
C1—N1—C7—N22.43 (14)C15—C14—C19—N3−177.97 (13)
Zn—N1—C7—N2−154.27 (9)N4—C14—C19—C18179.06 (13)
C1—N1—C7—C8−175.89 (11)C15—C14—C19—C180.5 (2)
Zn—N1—C7—C827.41 (17)C9—C8—C20—C121.52 (18)
C6—N2—C7—N1−1.44 (14)C7—C8—C20—C12−178.12 (11)
C6—N2—C7—C8176.92 (11)C11—C12—C20—C8−1.53 (19)
N1—C7—C8—C2025.18 (18)C13—C12—C20—C8178.26 (12)
N2—C7—C8—C20−152.96 (12)Zn—O1—C21—O210.67 (15)
N1—C7—C8—C9−154.45 (12)Zn—O1—C21—C22−165.93 (10)
N2—C7—C8—C927.41 (18)
Symmetry codes: (i) −x+1, y, −z+1/2.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N2—H2N···O30.87 (1)1.82 (1)2.6848 (14)174.(2)
N3—H3N···O1i0.86 (1)2.16 (1)3.0079 (14)171.(2)
O3—H3AO···N4ii0.84 (1)1.97 (1)2.8046 (16)175 (2)
O3—H3BO···O2iii0.84 (1)1.99 (1)2.8295 (15)179 (2)
Symmetry codes: (i) −x+1, y, −z+1/2; (ii) x, −y+1, z−1/2; (iii) x+1/2, y+1/2, −z+1/2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N2—H2N···O30.87 (1)1.82 (1)2.6848 (14)174.(2)
N3—H3N···O1i0.86 (1)2.16 (1)3.0079 (14)171.(2)
O3—H3AO···N4ii0.84 (1)1.97 (1)2.8046 (16)175 (2)
O3—H3BO···O2iii0.84 (1)1.99 (1)2.8295 (15)179 (2)
Symmetry codes: (i) −x+1, y, −z+1/2; (ii) x, −y+1, z−1/2; (iii) x+1/2, y+1/2, −z+1/2.
Acknowledgements top

We thank the Huangshi Institute of Technology (Grant No. 07yjz07A) for supporting this study.

references
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