PMCCPMCCPMCC

Search tips
Search criteria 

Advanced

 
Logo of actaeInternational Union of Crystallographysearchopen accessarticle submissionjournal home pagethis article
 
Acta Crystallogr Sect E Struct Rep Online. 2010 November 1; 66(Pt 11): o2831.
Published online 2010 October 20. doi:  10.1107/S1600536810040511
PMCID: PMC3009145

4,4′-Dimeth­oxy-2,2′-[(butane-1,4-diyldi­oxy)bis­(nitrilo­methyl­idyne)]diphenol

Abstract

The title Schiff base bis­oxime compound, C20H24N2O6, lies across an inversion centre and adopts an E configuration with respect to the C=N bond. In the mol­ecule, the oxime group is roughly coplanar with the benzene ring, forming a dihedral angle of 1.77 (2)°. An intra­molecular O—H(...)N hydrogen bond forms a six-membered ring with an S(6) motif. Weak inter­molecular C—H(...)O hydrogen bonding is present in the crystal structure.

Related literature

For applications of Schiff base compounds, see: Dong & Ding (2008 [triangle]); Dong et al. (2007 [triangle], 2009b [triangle]); Koizumi et al. (2005 [triangle]); Lu et al. (2006 [triangle]). For the synthesis, see: Dong et al. (2009a [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o2831-scheme1.jpg

Experimental

Crystal data

  • C20H24N2O6
  • M r = 388.41
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o2831-efi1.jpg
  • a = 4.7310 (4) Å
  • b = 17.1418 (16) Å
  • c = 12.2648 (12) Å
  • β = 90.981 (1)°
  • V = 994.50 (16) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.10 mm−1
  • T = 298 K
  • 0.50 × 0.22 × 0.18 mm

Data collection

  • Bruker SMART 1000 CCD area-detector diffractometer
  • 4976 measured reflections
  • 1765 independent reflections
  • 834 reflections with I > 2σ(I)
  • R int = 0.069

Refinement

  • R[F 2 > 2σ(F 2)] = 0.050
  • wR(F 2) = 0.149
  • S = 1.02
  • 1765 reflections
  • 128 parameters
  • H-atom parameters constrained
  • Δρmax = 0.17 e Å−3
  • Δρmin = −0.20 e Å−3

Data collection: SMART (Siemens, 1996 [triangle]); cell refinement: SAINT (Siemens, 1996 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810040511/xu5040sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810040511/xu5040Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

This work was supported by the Foundation of the Education Department of Gansu Province, China (No. 0904–11), which is gratefully acknowledged.

supplementary crystallographic information

Comment

Schiff base compounds are still one of the most prevalent mixed-donor ligands in coordination chemistry (Dong et al., 2007; Dong et al., 2008). In the past decades, a continuing attention has been drawn to the Schiff bases derived from benzaldehyde or salicylaldehyde and their metal complexes for the investigation of single molecule based magnetism, materials science, catalysis of many reactions which could be finely tuned by different substituent groups bonded to the phenolic ring (Koizumi et al., 2005; Dong et al., 2009b; Lu et al., 2006). Here, the structural characterization of the title compound, 4,4'-dimethoxy-2,2'- [(butane-1,4-diyldioxy)bis(nitrilomethylidyne)]diphenol, is reported.

The crystal structure of the title compound is built up by only the C20H24N2O6 molecules, in which all bond lengths are in normal ranges. The molecule, Fig. 1, lies across a crystallographic inversion centre (symmetry code: -x, -y, -z) and adopts an E configuration with respect to the C=N bond. The asymmetric unit of the compound is composed of one-half of the molecule. The oxime group is nearly coplanar with the benzene ring, making a dihedral angle of 1.77 (2)°. Within the molecule, the planar units are parallel but extend in opposite directions from the methylene bridge. The two benzene rings are parallel to each other with the dihedral angle of 0.00 (0)° and the distance of 1.664 (3) Å. An intramolecular O—H···N hydrogen bond forms a six-membered ring, producing an S(6) ring motif. In the crystal structure, each molecule links six other molecules into an infinite three-dimensional network supramolecular structure (Fig. 2 and 3), which is built from one-dimensional chains via three pairs of weak intermolecular C—H···O hydrogen bonds.

Experimental

The title compound was synthesized according to the references reported by Dong et al. (2009a). To an ethanol solution (8 ml) of 5-methoxy-2-hydroxybenzaldehyde (304.3 mg, 2 mmol) was added an ethanol solution (4 ml) of 1,4-bis(aminooxy)butane (120.2 mg, 1 mmol). The reaction mixture solution was stirred at 328 K for 4 h. After cooling to room temperature, the formed precipitate was filtered and washed successively with ethanol and ethanol-hexane (1:4), respectively. The product was dried under vacuum to yield 223.3 mg white microcrystal of the title compound. Yield, 52.6%. m.p. 398–399 K. Single crystals were obtained by slow evaporation from a solution of ethanol/dichloromethane (2:1) of the title compound at room temperature for several weeks. Anal. Calcd. for C20H24N2O6 (%): C, 61.84; H, 6.23; N, 7.21; O, 24.71. Found: C, 61.87; H, 6.25; N, 7.15; O, 24.75.

Refinement

H atoms were treated as riding atoms with distances C—H = 0.97 (CH2), 0.96 (CH3), 0.93 Å (aromatic) and O—H = 0.82 Å. Uiso(H) = 1.2Ueq(C) and 1.5Ueq(O).

Figures

Fig. 1.
The molecule structure of the title compound with atom numbering [Symmetry codes: -x,-y + 1,-z + 1]. Displacement ellipsoids for non-hydrogen atoms are drawn at the 30% probability level.
Fig. 2.
Part of the supramolecular structure of the title compound. Intermolecular hydrogen bonds are shown as dashed lines.
Fig. 3.
A view of the three-dimensional network for the title compound, and the hydrogen atoms are omitted for clarity.

Crystal data

C20H24N2O6F(000) = 412
Mr = 388.41Dx = 1.297 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 796 reflections
a = 4.7310 (4) Åθ = 2.4–24.5°
b = 17.1418 (16) ŵ = 0.10 mm1
c = 12.2648 (12) ÅT = 298 K
β = 90.981 (1)°Needle, pale-yellow
V = 994.50 (16) Å30.50 × 0.22 × 0.18 mm
Z = 2

Data collection

Bruker SMART 1000 CCD area-detector diffractometer834 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.069
graphiteθmax = 25.0°, θmin = 2.0°
[var phi] and ω scansh = −5→5
4976 measured reflectionsk = −20→18
1765 independent reflectionsl = −13→14

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.050Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.149H-atom parameters constrained
S = 1.02w = 1/[σ2(Fo2) + (0.0562P)2] where P = (Fo2 + 2Fc2)/3
1765 reflections(Δ/σ)max < 0.001
128 parametersΔρmax = 0.17 e Å3
0 restraintsΔρmin = −0.20 e Å3

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 (Å2)

xyzUiso*/Ueq
N10.4274 (5)0.32971 (13)0.62366 (17)0.0426 (7)
O10.2476 (4)0.37363 (10)0.55503 (13)0.0495 (6)
O20.6869 (5)0.27865 (12)0.80239 (14)0.0626 (7)
H20.57440.30540.76720.094*
O31.2686 (5)0.07207 (12)0.54439 (19)0.0669 (7)
C10.1003 (7)0.43013 (16)0.6187 (2)0.0494 (9)
H1A0.23360.46420.65620.059*
H1B−0.01470.40430.67260.059*
C2−0.0830 (7)0.47634 (15)0.5412 (2)0.0486 (9)
H2A−0.19980.51160.58290.058*
H2B−0.20800.44080.50210.058*
C30.5649 (7)0.27896 (16)0.5696 (2)0.0407 (8)
H30.53410.27520.49470.049*
C40.7676 (6)0.22699 (15)0.6220 (2)0.0381 (7)
C50.8222 (7)0.22862 (17)0.7338 (2)0.0453 (8)
C61.0185 (8)0.17800 (19)0.7794 (2)0.0586 (10)
H61.05210.17810.85440.070*
C71.1646 (8)0.12723 (18)0.7136 (3)0.0589 (10)
H71.29990.09420.74440.071*
C81.1118 (7)0.12492 (17)0.6016 (2)0.0500 (9)
C90.9145 (6)0.17495 (16)0.5571 (2)0.0420 (8)
H90.87870.17400.48230.050*
C101.2332 (8)0.07222 (19)0.4288 (3)0.0747 (12)
H10A1.04140.05890.40990.112*
H10B1.35880.03470.39750.112*
H10C1.27570.12320.40100.112*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
N10.0462 (19)0.0427 (14)0.0387 (13)0.0063 (13)−0.0049 (12)0.0047 (12)
O10.0589 (16)0.0474 (12)0.0419 (11)0.0167 (12)−0.0083 (11)−0.0002 (9)
O20.0703 (18)0.0798 (15)0.0374 (11)0.0180 (14)−0.0085 (11)−0.0050 (11)
O30.0670 (19)0.0583 (14)0.0752 (16)0.0223 (14)−0.0005 (14)0.0021 (12)
C10.055 (2)0.0477 (19)0.0452 (18)0.0095 (17)0.0034 (16)0.0005 (15)
C20.049 (2)0.0423 (18)0.0547 (19)0.0086 (16)0.0037 (16)0.0033 (13)
C30.048 (2)0.0414 (16)0.0321 (14)−0.0018 (17)−0.0055 (14)0.0026 (14)
C40.040 (2)0.0387 (16)0.0355 (15)0.0004 (16)−0.0056 (14)0.0095 (13)
C50.050 (2)0.0496 (19)0.0362 (16)0.0034 (17)−0.0045 (15)0.0030 (14)
C60.065 (3)0.072 (2)0.0387 (17)0.001 (2)−0.0138 (17)0.0172 (17)
C70.052 (2)0.061 (2)0.064 (2)0.010 (2)−0.0105 (19)0.0201 (18)
C80.053 (2)0.0422 (18)0.0547 (19)0.0016 (18)−0.0003 (18)0.0074 (16)
C90.048 (2)0.0396 (16)0.0382 (16)0.0009 (16)−0.0062 (15)0.0078 (13)
C100.083 (3)0.068 (2)0.074 (3)0.017 (2)0.018 (2)−0.0021 (19)

Geometric parameters (Å, °)

N1—C31.278 (3)C3—H30.9300
N1—O11.405 (3)C4—C91.390 (4)
O1—C11.432 (3)C4—C51.391 (4)
O2—C51.368 (3)C5—C61.382 (4)
O2—H20.8200C6—C71.381 (4)
O3—C81.372 (3)C6—H60.9300
O3—C101.425 (3)C7—C81.392 (4)
C1—C21.501 (3)C7—H70.9300
C1—H1A0.9700C8—C91.374 (4)
C1—H1B0.9700C9—H90.9300
C2—C2i1.524 (5)C10—H10A0.9600
C2—H2A0.9700C10—H10B0.9600
C2—H2B0.9700C10—H10C0.9600
C3—C41.451 (4)
C3—N1—O1111.2 (2)O2—C5—C6117.6 (3)
N1—O1—C1109.33 (19)O2—C5—C4122.5 (3)
C5—O2—H2109.5C6—C5—C4119.9 (3)
C8—O3—C10116.9 (2)C7—C6—C5119.9 (3)
O1—C1—C2107.0 (2)C7—C6—H6120.0
O1—C1—H1A110.3C5—C6—H6120.0
C2—C1—H1A110.3C6—C7—C8120.8 (3)
O1—C1—H1B110.3C6—C7—H7119.6
C2—C1—H1B110.3C8—C7—H7119.6
H1A—C1—H1B108.6O3—C8—C9125.3 (3)
C1—C2—C2i113.7 (3)O3—C8—C7115.7 (3)
C1—C2—H2A108.8C9—C8—C7118.9 (3)
C2i—C2—H2A108.8C8—C9—C4121.1 (3)
C1—C2—H2B108.8C8—C9—H9119.5
C2i—C2—H2B108.8C4—C9—H9119.5
H2A—C2—H2B107.7O3—C10—H10A109.5
N1—C3—C4121.8 (3)O3—C10—H10B109.5
N1—C3—H3119.1H10A—C10—H10B109.5
C4—C3—H3119.1O3—C10—H10C109.5
C9—C4—C5119.4 (3)H10A—C10—H10C109.5
C9—C4—C3118.3 (2)H10B—C10—H10C109.5
C5—C4—C3122.3 (3)
C3—N1—O1—C1−179.4 (2)C4—C5—C6—C71.5 (5)
N1—O1—C1—C2178.8 (2)C5—C6—C7—C8−1.6 (5)
O1—C1—C2—C2i−64.3 (4)C10—O3—C8—C93.4 (5)
O1—N1—C3—C4179.2 (2)C10—O3—C8—C7−175.7 (3)
N1—C3—C4—C9−178.2 (3)C6—C7—C8—O3−179.8 (3)
N1—C3—C4—C50.7 (5)C6—C7—C8—C91.0 (5)
C9—C4—C5—O2179.6 (3)O3—C8—C9—C4−179.5 (3)
C3—C4—C5—O20.7 (5)C7—C8—C9—C4−0.3 (5)
C9—C4—C5—C6−0.8 (4)C5—C4—C9—C80.3 (4)
C3—C4—C5—C6−179.7 (3)C3—C4—C9—C8179.2 (3)
O2—C5—C6—C7−178.9 (3)

Symmetry codes: (i) −x, −y+1, −z+1.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O2—H2···N10.821.932.643 (2)145
C3—H3···O2ii0.932.653.481 (3)150
C9—H9···O2ii0.932.513.382 (3)157
C10—H10A···O3iii0.962.743.448 (4)131

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: XU5040).

References

  • Dong, W.-K., Chen, X., Wang, S.-J., He, X.-N., Wu, H.-L. & Yu, T.-Z. (2007). Synth. React. Inorg. Met. Org. Nano-Met. Chem.37, 229–233.
  • Dong, W.-K. & Ding, Y. J. (2008). Cryst. Res. Technol.43, 321–326.
  • Dong, W.-K., Duan, J.-G., Guan, Y.-H., Shi, J.-Y. & Zhao, C.-Y. (2009a). Inorg. Chim. Acta, 362, 1129–1134.
  • Dong, W.-K., He, X.-N., Yan, H.-B., Lv, Z.-W., Chen, X., Zhao, C.-Y. & Tang, X.-L. (2009b). Polyhedron, 28, 1419–1428.
  • Koizumi, S., Nihei, M., Nakano, M. & Oshio, H. (2005). Inorg. Chem.44, 1208–1210. [PubMed]
  • Lu, Z.-L., Yuan, M., Pan, F., Gao, S., Zhang, D.-Q. & Zhu, D.-B. (2006). Inorg. Chem.45, 3538–3548. [PubMed]
  • Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. [PubMed]
  • Siemens (1996). SMART and SAINT Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.

Articles from Acta Crystallographica Section E: Structure Reports Online are provided here courtesy of International Union of Crystallography