metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890
Volume 66| Part 10| October 2010| Pages m1306-m1307

Bis[2-(1H-benzimidazol-2-yl)benzoato]copper(II) dihydrate

aZhongshan Polytechnic, Zhongshan, Guangdong 528404, People's Republic of China
*Correspondence e-mail: wangjun7203@126.com

(Received 15 September 2010; accepted 20 September 2010; online 30 September 2010)

In the title compound, [Cu(C14H9N2O2)2]·2H2O, the Cu(II) ion lies on a centre of symmetry and is four-coordinated by two N atoms and two O atoms from two 2-(1H-benzimidazol-2-yl)benzoate ligands in a square-planar environment. The benzimidazol and benzyl rings form a dihedral angle of 42.8 (5)°. The mol­ecule contains two H-bonded carboxyl O acceptors and two H-bonded N—H donors in the benzimidazol groups, which inter­act with two symmetry-related uncoordinated water mol­ecules so that neighboring mol­ecular units are linked by (O—H)water⋯Ocarbox­yl hydrogen bonds with an R24(8) graph-set motif, generating a helical chain in the a-axis direction. These chains are, in turn, inter­connected by (N—H)benzimidazol⋯Owater hydrogen bonds, forming a three-dimensional supra­molecular network.

Related literature

For the structural diversity and potential applications in functional materials of metal coordination polymers based on benzimidazole derivatives, see: Aminabhavi et al. (1986[Aminabhavi, T. M., Biradar, N. S., Patil, S. B. & Hoffman, D. E. (1986). Inorg. Chim. Acta, 125, 125-128.]); Isele et al. (2005[Isele, K., Franz, P., Ambrus, C., Bernardinelli, G., Decurtins, S. & Williams, A. F. (2005). Inorg. Chem. 44, 3896-3906.]). For similar structures, see: Che et al. (2006[Che, G.-B., Sun, J., Liu, C.-B. & Xu, Z.-L. (2006). Acta Cryst. E62, m3101-m3103.]); Fang et al. (2006[Fang, X.-N., Xiao, Y.-A., Sui, Y., Chen, H.-M. & Zuo, C.-P. (2006). Acta Cryst. E62, m2519-m2521.]); Liu et al. (2004[Liu, F. C., Duan, L. Y., Li, Y. G., Wang, E. B., Wang, X. L., Hu, C. W. & Xu, L. (2004). Inorg. Chim. Acta, 357, 1355-1359.]); Li et al. (2010[Li, S. L., Lan, Y. Q., Ma, J. C., Ma, J. F. & Su, Z. M. (2010). Cryst. Growth Des. 10, 1161-1170.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • [Cu(C14H9N2O2)2]·2H2O

  • Mr = 574.04

  • Monoclinic, P 21 /c

  • a = 11.6235 (2) Å

  • b = 7.6920 (2) Å

  • c = 16.1410 (3) Å

  • β = 115.735 (1)°

  • V = 1299.99 (5) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.89 mm−1

  • T = 296 K

  • 0.23 × 0.21 × 0.16 mm

Data collection
  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2008a[Sheldrick, G. M. (2008a). SADABS. University of Göttingen, Germany.]) Tmin = 0.821, Tmax = 0.871

  • 14480 measured reflections

  • 2974 independent reflections

  • 1854 reflections with I > 2σ(I)

  • Rint = 0.063

Refinement
  • R[F2 > 2σ(F2)] = 0.046

  • wR(F2) = 0.110

  • S = 1.00

  • 2974 reflections

  • 178 parameters

  • H-atom parameters constrained

  • Δρmax = 0.29 e Å−3

  • Δρmin = −0.33 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2A⋯O1W 0.86 1.86 2.716 (3) 173
O1W—H1W⋯O2i 0.84 1.89 2.720 (3) 167
O1W—H2W⋯O2ii 0.84 1.94 2.763 (3) 165
Symmetry codes: (i) [x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (ii) [-x+2, y+{\script{1\over 2}}, -z+{\script{3\over 2}}].

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX2 and SAINT. Bruker AXS Inc, Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2004[Bruker (2004). APEX2 and SAINT. Bruker AXS Inc, Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b[Sheldrick, G. M. (2008b). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008b[Sheldrick, G. M. (2008b). Acta Cryst. A64, 112-122.]); molecular graphics: XP in SHELXTL (Sheldrick, 2008b[Sheldrick, G. M. (2008b). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Metal coordination polymers based on benzimidazole derivatives have raised intense interest for their structural diversity and their potential applications in functional materials (Aminabhavi et al., 1986; Isele et al., 2005). To date, numerous one-, two-, and three-dimensional coordination polymers have been synthesized by the choice of appropriate metal ions and versatile benzimidazole derivatives as ligands (Che et al., 2006; Fang et al., 2006; Liu et al., 2004; Li et al., 2010). Herein, the condensation of 1,2-diaminobenzene with 2-formylbenzoic acid in the presence of copper acetate lead to a new structure, Cu(C14H9N2O2)2.2H2O, the title compound herein reported .

As depicted in Fig. 1, the CuII ion lies on a centre of symmetry and is four-coordinated by two N atoms and two O atoms from two 2-(1H-Benzimidazol-2-yl)benzoate ligands in a square planar environment. The planar benzimidazol and benzyl rings form a dihedral angle of 42.8 (5)°. The molecule contains two H-bonded carboxyl O acceptors and two H-bonded N—H donors in the benzimidazol groups which interact with two symmetry-related lattice water molecules (symmetry code: 2 - X, 2 - Y, 2 - Z) in a way that neighboring molecular units are linked by (O—H)water···Ocarbox hydrogen bonding with an R24(8) graph set motif (Bernstein et al., 1995) to generate a helical chain in the a-axis direction. These chains are in turn interconnected by (N—H)benzimidazol···Owater hydrogen bonds and extend to form a three-dimensional supramolecular network (table 1; Fig. 2)

Related literature top

For the structural diversity and potential applications in functional materials of metal coordination polymers based on benzimidazole derivatives, see: Aminabhavi et al. (1986); Isele et al. (2005). For similar structures, see: Che et al. (2006); Fang et al. (2006); Liu et al. (2004); Li et al. (2010). For hydrogen-bond motifs, see: Bernstein et al. (1995).

Experimental top

The condensation reaction was done by reflux of 1,2-diaminobenzene (1.081 g; 10 mmol), 2-formylbenzoic acid (1.501 g; 10 mmol) and copper acetate (1.99 g; 10 mmol) in a hot 75% methanol/water (3:1; v/v) mixture (50 mL). Blue block crystals of the compound suitable for single-crystal X-ray diffraction analysis were obtained at room temperature by slow evaporation of the solvent (Yield 56% based on Cu).

Refinement top

All water H atoms were tentatively located in difference density Fourier maps and were refined with O–H distance restraints of 0.83 (1) Å and with Uiso(H) = 1.5 Ueq(O). In the last stage of refinement, they were treated as riding on their parent O atoms. All H atoms attached to C and N atoms were fixed geometrically and treated as riding with C—H = 0.93 Å and N—H = 0.86 Å, and Uiso(H) = 1.2Ueq(C) and Uiso(H) = 1.5Ueq(N).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008b); molecular graphics: XP in SHELXTL (Sheldrick, 2008b); software used to prepare material for publication: SHELXTL (Sheldrick, 2008b).

Figures top
[Figure 1] Fig. 1. ORTEP represention of atom numbering diagram for (I), showing 30% probability displacement ellipsoids. Unlabelled atoms are related to the labelled atoms by the symmetry operator (i): 1-x, 1-y, 1-z.
[Figure 2] Fig. 2. View of the three-dimensional structure of the title compound.
Bis[2-(1H-benzimidazol-2-yl)benzoato]copper(II) dihydrate top
Crystal data top
[Cu(C14H9N2O2)2]·2H2OF(000) = 590
Mr = 574.04Dx = 1.466 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 4800 reflections
a = 11.6235 (2) Åθ = 1.4–28.0°
b = 7.6920 (2) ŵ = 0.89 mm1
c = 16.1410 (3) ÅT = 296 K
β = 115.735 (1)°Block, blue
V = 1299.99 (5) Å30.23 × 0.21 × 0.16 mm
Z = 2
Data collection top
Bruker APEXII CCD area-detector
diffractometer
2974 independent reflections
Radiation source: fine-focus sealed tube1854 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.063
ϕ and ω scanθmax = 27.5°, θmin = 1.9°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008a)
h = 1514
Tmin = 0.821, Tmax = 0.871k = 99
14480 measured reflectionsl = 2020
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)] = 0.046Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.110H-atom parameters constrained
S = 1.00 w = 1/[σ2(Fo2) + (0.0379P)2 + 0.7646P]
where P = (Fo2 + 2Fc2)/3
2974 reflections(Δ/σ)max = 0.001
178 parametersΔρmax = 0.29 e Å3
0 restraintsΔρmin = 0.33 e Å3
Crystal data top
[Cu(C14H9N2O2)2]·2H2OV = 1299.99 (5) Å3
Mr = 574.04Z = 2
Monoclinic, P21/cMo Kα radiation
a = 11.6235 (2) ŵ = 0.89 mm1
b = 7.6920 (2) ÅT = 296 K
c = 16.1410 (3) Å0.23 × 0.21 × 0.16 mm
β = 115.735 (1)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer
2974 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008a)
1854 reflections with I > 2σ(I)
Tmin = 0.821, Tmax = 0.871Rint = 0.063
14480 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0460 restraints
wR(F2) = 0.110H-atom parameters constrained
S = 1.00Δρmax = 0.29 e Å3
2974 reflectionsΔρmin = 0.33 e Å3
178 parameters
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
Cu10.50000.50000.50000.03258 (17)
C10.5169 (3)0.8319 (4)0.6049 (2)0.0354 (7)
C20.4078 (3)0.9168 (4)0.5430 (2)0.0439 (8)
H20.35190.86480.48830.053*
C30.3861 (4)1.0813 (5)0.5665 (3)0.0511 (9)
H30.31391.14140.52650.061*
C40.4686 (4)1.1600 (5)0.6478 (3)0.0582 (10)
H40.45081.27210.66050.070*
C50.5758 (4)1.0775 (5)0.7099 (3)0.0535 (10)
H50.63021.13010.76490.064*
C60.5994 (3)0.9111 (4)0.6870 (2)0.0400 (8)
C70.6757 (3)0.6520 (4)0.6772 (2)0.0332 (7)
C80.7588 (3)0.4981 (4)0.7070 (2)0.0358 (7)
C90.8024 (3)0.4489 (5)0.7992 (2)0.0504 (9)
H90.77790.51260.83780.060*
C100.8814 (4)0.3068 (5)0.8332 (3)0.0632 (11)
H100.90960.27500.89450.076*
C110.9187 (3)0.2119 (5)0.7768 (3)0.0604 (11)
H110.97000.11410.79940.072*
C120.8798 (3)0.2620 (4)0.6868 (2)0.0502 (9)
H120.90750.19950.64950.060*
C130.7996 (3)0.4051 (4)0.6504 (2)0.0367 (7)
C140.7735 (3)0.4580 (4)0.5535 (2)0.0386 (8)
N10.5679 (2)0.6681 (3)0.60034 (16)0.0327 (6)
N20.6971 (2)0.7946 (3)0.73035 (17)0.0413 (7)
H2A0.76140.81030.78280.050*
O10.66231 (18)0.4956 (3)0.49508 (13)0.0392 (5)
O20.8661 (2)0.4584 (4)0.53508 (16)0.0636 (8)
O1W0.8855 (2)0.8417 (3)0.90275 (15)0.0624 (7)
H1W0.86800.89790.94060.094*
H2W0.96180.86570.91440.094*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu10.0257 (3)0.0338 (3)0.0323 (3)0.0030 (3)0.0070 (2)0.0034 (3)
C10.0397 (19)0.0320 (17)0.0387 (18)0.0002 (14)0.0210 (15)0.0016 (15)
C20.042 (2)0.0385 (19)0.049 (2)0.0043 (16)0.0178 (17)0.0018 (17)
C30.054 (2)0.041 (2)0.066 (3)0.0104 (19)0.034 (2)0.0083 (19)
C40.074 (3)0.033 (2)0.087 (3)0.0080 (19)0.053 (3)0.003 (2)
C50.064 (3)0.042 (2)0.061 (2)0.0088 (19)0.032 (2)0.0177 (19)
C60.042 (2)0.0360 (18)0.046 (2)0.0016 (16)0.0223 (17)0.0025 (16)
C70.0321 (17)0.0363 (18)0.0308 (16)0.0041 (14)0.0132 (14)0.0034 (14)
C80.0265 (15)0.0371 (16)0.0371 (17)0.0048 (16)0.0076 (13)0.0013 (16)
C90.050 (2)0.056 (2)0.041 (2)0.0050 (17)0.0153 (17)0.0057 (16)
C100.059 (3)0.073 (3)0.047 (2)0.009 (2)0.014 (2)0.022 (2)
C110.051 (2)0.059 (2)0.066 (3)0.023 (2)0.021 (2)0.029 (2)
C120.043 (2)0.051 (2)0.058 (2)0.0089 (17)0.0228 (18)0.0113 (18)
C130.0288 (17)0.0374 (18)0.0396 (18)0.0014 (14)0.0109 (14)0.0048 (15)
C140.0335 (19)0.038 (2)0.0420 (19)0.0006 (14)0.0142 (16)0.0020 (14)
N10.0292 (14)0.0314 (14)0.0326 (14)0.0024 (11)0.0089 (11)0.0040 (11)
N20.0385 (16)0.0449 (17)0.0335 (14)0.0063 (13)0.0090 (12)0.0094 (13)
O10.0296 (12)0.0483 (13)0.0362 (12)0.0045 (11)0.0111 (9)0.0010 (11)
O20.0334 (14)0.109 (2)0.0530 (15)0.0133 (14)0.0232 (12)0.0240 (14)
O1W0.0453 (15)0.0879 (19)0.0496 (15)0.0167 (14)0.0165 (12)0.0258 (14)
Geometric parameters (Å, º) top
Cu1—O1i1.9227 (19)C7—C81.470 (4)
Cu1—O11.9227 (19)C8—C131.396 (4)
Cu1—N11.951 (2)C8—C91.400 (4)
Cu1—N1i1.951 (2)C9—C101.379 (5)
C1—C21.390 (4)C9—H90.9300
C1—C61.395 (4)C10—C111.376 (5)
C1—N11.407 (4)C10—H100.9300
C2—C31.374 (5)C11—C121.376 (5)
C2—H20.9300C11—H110.9300
C3—C41.384 (5)C12—C131.396 (4)
C3—H30.9300C12—H120.9300
C4—C51.370 (5)C13—C141.513 (4)
C4—H40.9300C14—O21.235 (4)
C5—C61.392 (5)C14—O11.259 (3)
C5—H50.9300N2—H2A0.8600
C6—N21.376 (4)O1W—H1W0.8415
C7—N11.333 (3)O1W—H2W0.8432
C7—N21.347 (3)
O1i—Cu1—O1180.0C13—C8—C7124.1 (3)
O1i—Cu1—N190.25 (9)C9—C8—C7116.6 (3)
O1—Cu1—N189.75 (9)C10—C9—C8120.6 (3)
O1i—Cu1—N1i89.75 (9)C10—C9—H9119.7
O1—Cu1—N1i90.25 (9)C8—C9—H9119.7
N1—Cu1—N1i180.0C11—C10—C9120.2 (3)
C2—C1—C6120.9 (3)C11—C10—H10119.9
C2—C1—N1131.1 (3)C9—C10—H10119.9
C6—C1—N1108.0 (3)C12—C11—C10119.8 (3)
C3—C2—C1117.0 (3)C12—C11—H11120.1
C3—C2—H2121.5C10—C11—H11120.1
C1—C2—H2121.5C11—C12—C13121.3 (3)
C2—C3—C4122.0 (3)C11—C12—H12119.4
C2—C3—H3119.0C13—C12—H12119.4
C4—C3—H3119.0C8—C13—C12118.9 (3)
C5—C4—C3121.8 (3)C8—C13—C14124.4 (3)
C5—C4—H4119.1C12—C13—C14116.4 (3)
C3—C4—H4119.1O2—C14—O1122.5 (3)
C4—C5—C6116.9 (3)O2—C14—C13116.4 (3)
C4—C5—H5121.5O1—C14—C13121.1 (3)
C6—C5—H5121.5C7—N1—C1106.4 (2)
N2—C6—C5132.7 (3)C7—N1—Cu1126.1 (2)
N2—C6—C1105.9 (3)C1—N1—Cu1127.5 (2)
C5—C6—C1121.4 (3)C7—N2—C6108.8 (3)
N1—C7—N2110.9 (3)C7—N2—H2A125.6
N1—C7—C8126.7 (3)C6—N2—H2A125.6
N2—C7—C8122.3 (3)C14—O1—Cu1132.8 (2)
C13—C8—C9119.2 (3)H1W—O1W—H2W106.7
Symmetry code: (i) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···O1W0.861.862.716 (3)173
O1W—H1W···O2ii0.841.892.720 (3)167
O1W—H2W···O2iii0.841.942.763 (3)165
Symmetry codes: (ii) x, y+3/2, z+1/2; (iii) x+2, y+1/2, z+3/2.

Experimental details

Crystal data
Chemical formula[Cu(C14H9N2O2)2]·2H2O
Mr574.04
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)11.6235 (2), 7.6920 (2), 16.1410 (3)
β (°) 115.735 (1)
V3)1299.99 (5)
Z2
Radiation typeMo Kα
µ (mm1)0.89
Crystal size (mm)0.23 × 0.21 × 0.16
Data collection
DiffractometerBruker APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2008a)
Tmin, Tmax0.821, 0.871
No. of measured, independent and
observed [I > 2σ(I)] reflections
14480, 2974, 1854
Rint0.063
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.046, 0.110, 1.00
No. of reflections2974
No. of parameters178
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.29, 0.33

Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008b), SHELXL97 (Sheldrick, 2008b), XP in SHELXTL (Sheldrick, 2008b), SHELXTL (Sheldrick, 2008b).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···O1W0.861.862.716 (3)172.6
O1W—H1W···O2i0.841.892.720 (3)167.4
O1W—H2W···O2ii0.841.942.763 (3)165.4
Symmetry codes: (i) x, y+3/2, z+1/2; (ii) x+2, y+1/2, z+3/2.
 

Acknowledgements

This work was supported by Zhongshan Polytechnic.

References

First citationAminabhavi, T. M., Biradar, N. S., Patil, S. B. & Hoffman, D. E. (1986). Inorg. Chim. Acta, 125, 125–128.  CrossRef CAS Web of Science Google Scholar
First citationBernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. 34, 1555–1573.  CrossRef CAS Web of Science Google Scholar
First citationBruker (2004). APEX2 and SAINT. Bruker AXS Inc, Madison, Wisconsin, USA.  Google Scholar
First citationChe, G.-B., Sun, J., Liu, C.-B. & Xu, Z.-L. (2006). Acta Cryst. E62, m3101–m3103.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationFang, X.-N., Xiao, Y.-A., Sui, Y., Chen, H.-M. & Zuo, C.-P. (2006). Acta Cryst. E62, m2519–m2521.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationIsele, K., Franz, P., Ambrus, C., Bernardinelli, G., Decurtins, S. & Williams, A. F. (2005). Inorg. Chem. 44, 3896–3906.  Web of Science CSD CrossRef PubMed CAS Google Scholar
First citationLi, S. L., Lan, Y. Q., Ma, J. C., Ma, J. F. & Su, Z. M. (2010). Cryst. Growth Des. 10, 1161–1170.  Web of Science CSD CrossRef CAS Google Scholar
First citationLiu, F. C., Duan, L. Y., Li, Y. G., Wang, E. B., Wang, X. L., Hu, C. W. & Xu, L. (2004). Inorg. Chim. Acta, 357, 1355–1359.  Web of Science CSD CrossRef CAS Google Scholar
First citationSheldrick, G. M. (2008a). SADABS. University of Göttingen, Germany.  Google Scholar
First citationSheldrick, G. M. (2008b). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar

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ISSN: 2056-9890
Volume 66| Part 10| October 2010| Pages m1306-m1307
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