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Acta Crystallogr Sect E Struct Rep Online. 2009 May 1; 65(Pt 5): o1061.
Published online 2009 April 18. doi:  10.1107/S1600536809013579
PMCID: PMC2977741

2-[(E)-2,5-Dimethoxy­benzyl­idene]indan-1-one

Abstract

In the title compound, C18H16O3, the mean plane of the nine-membered indane system makes a dihedral angle of 3.71 (17)° with the benzene ring of the dimethoxy­phenyl group. The mol­ecular conformation is stabilized by intra­molecular C—H(...)O hydrogen contacts. The crystal structure is stabilized by inter­molecular C—H(...)O inter­actions, which link neighbouring mol­ecules into one-dimensional extended chains along the [100] direction. In the structure, C—H(...)π inter­actions are also observed.

Related literature

For styryl dyes and their applications, see: Ying et al. (1990 [triangle]); He et al. (1995 [triangle]). For bond-length data, see: Allen et al. (1987 [triangle]). For details of the Flack parameter, see: Flack & Schwarzenbach (1988 [triangle]).

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Object name is e-65-o1061-scheme1.jpg

Experimental

Crystal data

  • C18H16O3
  • M r = 280.31
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1061-efi1.jpg
  • a = 12.925 (3) Å
  • b = 20.163 (5) Å
  • c = 5.451 (1) Å
  • V = 1420.6 (5) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 296 K
  • 0.38 × 0.09 × 0.04 mm

Data collection

  • Bruker Kappa APEXII CCD area-detector diffractometer
  • Absorption correction: none
  • 8980 measured reflections
  • 1944 independent reflections
  • 856 reflections with I > 2σ(I)
  • R int = 0.107

Refinement

  • R[F 2 > 2σ(F 2)] = 0.055
  • wR(F 2) = 0.115
  • S = 0.97
  • 1944 reflections
  • 192 parameters
  • 1 restraint
  • H-atom parameters constrained
  • Δρmax = 0.17 e Å−3
  • Δρmin = −0.16 e Å−3

Data collection: APEX2 (Bruker, 2007 [triangle]); cell refinement: APEX2; data reduction: SAINT (Bruker, 2007 [triangle]); program(s) used to solve structure: SIR97 (Altomare et al., 1999 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]) and PLATON (Spek, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809013579/jh2077sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809013579/jh2077Isup2.hkl

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

Acknowledgments

AMA acknowledges the Chemistry Department, Faculty of Science, King Abdul-Aziz Universty, for providing the laboratories and facilities.

supplementary crystallographic information

Comment

Nonlinear optical (NLO) properties of organics have been the subject of numerous investigations in the recent years, due to their potential applications in the field of photonics. A good NLO organic material should generally contain donor and acceptor groups positioned at either ends of a conjugation path of appropriate length. The increased effective conjugation and hence, the large π-delocalization length, has been recognized as a factor leading to large third order nonlinearities. Styryl dyes are organic molecules possessing charge donor and acceptor groups, conjugated through π-electronic bridge, suitable for NLO device applications. They are widely used as optical recording medium in laser disks, laser dyes (Ying et al., 1990) and optical sensitizers in various other fields (He et al., 1995).

In the title compound (I) (Fig. 1), all bond lengths (Allen et al., 1987) and angles are within normal ranges. The nine-membered indane ring is almost planar, with the maximum deviations of -0.017 (4) and 0.021 (4) Å for atoms C6 and C8, respectively. The mean plane of the indane ring makes a dihedral angle of 3.71 (17) °, with the benzene ring of the dimethoxy phenyl group.

The molecular conformation is stabilized by intramolecular C—H···O hydrogen contacts (Table 1). The crystal structure is stabilized by intermolecular C—H···O interactions, which link neighbouring molecules into 1-D extended chains along the [100] direction (Fig. 2). In the structure, C—H···π interactions are also observed (Table 1).

Experimental

An equivalent molar quantities of 2,5-dimethoxybenzaldehyde (4.40 g, 26.5 mmol) and 1-indanone (3.5 g, 26.5 mmol) were dissolved in 25 ml e thanol, and then heated at reflux. Pipyridine (1 ml) was added to the solution, and reflux was continued for 5 h. The solution was cooled to room temperature, and the solid products were filtered, and washed with ethanol (25 ml) to give yellow crystals. [Yield: 5.79 g, 91%; m.p. 403 - 404 K]. IR (cm-1) 1689 (C=O), 1614 (C=C). 1H-NMR (CDCl3): 3.82 (3H, s, CH3O), 3.83 (3H, s, CH3O), 4.04 (2H, s, CH2), 6.83 (1H, d, J = 9 Hz), 6.94 (1H, dd, J1 = 1.8 Hz, J2 = 6 Hz), 7.23 (1H, d, J = 3 Hz), 7.40 (1H, dd, J = 7.2 Hz, J2 = 7.1 Hz), 7.54 (1H, d, J = 7.8 Hz), 7.6 (1H, d, J = 4.2 Hz), 7.9 (1H, d, J = 9 Hz), 8.1 (1H, s, CH=C).

Refinement

All H atoms bonded to the C atoms were positioned geometrically, with C—H distances in the range 0.93–0.97 Å, and refined using a riding approximation model, with Uiso(H) = 1.5Ueq of the carrier atom for methyl H and 1.2Ueq for the remaining H atoms. The calculation of the Flack (Flack & Schwarzenbach, 1988) parameter was suppressed by the use of the MERG 4 instruction in SHELXL97 (Sheldrick, 2008), as the lack of anomalous scatterers did not allow the determination of the absolute configuration from the X-ray measurements.

Figures

Fig. 1.
Molecular structure of (I), showing the atom labeling scheme and displacement ellipsoids are drawn at the 50% probability level. Hydrogen atoms are drawn as spheres of arbitrary radii.
Fig. 2.
The crystal packing of the title compound, viewed down the c-axis, showing intermolecular C—H···O interactions (dashed lines). H atoms not involved in the hydrogen bonding have been omitted for clarity.

Crystal data

C18H16O3F(000) = 592
Mr = 280.31Dx = 1.311 Mg m3
Orthorhombic, Pna21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2nCell parameters from 598 reflections
a = 12.925 (3) Åθ = 2.6–18.0°
b = 20.163 (5) ŵ = 0.09 mm1
c = 5.451 (1) ÅT = 296 K
V = 1420.6 (5) Å3Prism, yellow
Z = 40.38 × 0.09 × 0.04 mm

Data collection

Bruker Kappa APEXII CCD area-detector diffractometer856 reflections with I > 2σ(I)
Radiation source: sealed tubeRint = 0.107
graphiteθmax = 28.3°, θmin = 2.6°
[var phi] and ω scansh = −16→17
8980 measured reflectionsk = −26→25
1944 independent reflectionsl = −7→4

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)] = 0.055Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.115H-atom parameters constrained
S = 0.97w = 1/[σ2(Fo2) + (0.037P)2] where P = (Fo2 + 2Fc2)/3
1944 reflections(Δ/σ)max < 0.001
192 parametersΔρmax = 0.17 e Å3
1 restraintΔρmin = −0.16 e Å3

Special details

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles
Refinement. Refinement on F2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating -R-factor-obs 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
O10.4588 (2)0.22227 (16)0.5837 (6)0.0619 (13)
O20.4627 (2)0.38576 (15)1.1861 (5)0.0507 (11)
O30.8608 (2)0.47706 (17)1.0485 (6)0.0683 (16)
C10.6059 (3)0.2111 (2)0.3166 (8)0.0400 (16)
C20.5790 (3)0.1610 (2)0.1549 (9)0.0507 (17)
C30.6488 (3)0.1442 (2)−0.0268 (9)0.0533 (17)
C40.7428 (4)0.1762 (2)−0.0452 (8)0.0553 (19)
C50.7699 (3)0.2264 (2)0.1200 (8)0.0460 (17)
C60.6999 (3)0.2433 (2)0.3014 (7)0.0360 (14)
C70.7111 (3)0.2962 (2)0.4948 (7)0.0347 (14)
C80.6098 (3)0.2932 (2)0.6309 (7)0.0350 (14)
C90.5446 (3)0.2392 (2)0.5186 (7)0.0423 (16)
C100.5726 (3)0.3277 (2)0.8213 (8)0.0357 (14)
C110.6191 (3)0.3804 (2)0.9655 (7)0.0327 (14)
C120.5612 (3)0.4089 (2)1.1572 (7)0.0353 (14)
C130.6046 (3)0.4569 (2)1.3073 (8)0.0423 (17)
C140.7049 (3)0.4787 (2)1.2631 (8)0.0450 (17)
C150.7623 (3)0.4521 (2)1.0747 (9)0.0430 (17)
C160.7202 (3)0.4039 (2)0.9271 (7)0.0393 (16)
C170.4010 (3)0.4138 (2)1.3758 (8)0.0570 (19)
C180.9112 (3)0.4649 (3)0.8234 (10)0.072 (2)
H20.515700.139300.168300.0600*
H30.632200.11080−0.138100.0640*
H40.788800.16430−0.168900.0670*
H50.833400.247900.108000.0550*
H7A0.768700.286600.603200.0410*
H7B0.721300.339400.421100.0410*
H100.506000.316000.869000.0430*
H130.566700.474601.436900.0500*
H140.733500.511501.361900.0540*
H160.759400.386400.799400.0470*
H17A0.432300.404801.532100.0860*
H17B0.333000.394701.371000.0860*
H17C0.396100.460901.352400.0860*
H18A0.925400.418300.808300.1070*
H18B0.975000.489200.818200.1070*
H18C0.867500.478800.690600.1070*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0348 (17)0.084 (3)0.067 (2)−0.0157 (19)0.0072 (17)−0.021 (2)
O20.0369 (17)0.064 (2)0.0512 (19)−0.0076 (17)0.0123 (17)−0.0217 (17)
O30.055 (2)0.084 (3)0.066 (3)−0.0298 (19)−0.003 (2)−0.007 (2)
C10.050 (3)0.038 (3)0.032 (2)0.004 (2)−0.007 (3)−0.005 (3)
C20.054 (3)0.051 (3)0.047 (3)−0.001 (2)−0.010 (3)−0.010 (3)
C30.062 (3)0.048 (3)0.050 (3)0.009 (3)−0.003 (3)−0.014 (3)
C40.063 (3)0.059 (4)0.044 (3)0.027 (3)0.005 (3)−0.006 (3)
C50.047 (3)0.051 (3)0.040 (3)0.011 (2)0.002 (2)−0.005 (3)
C60.034 (2)0.041 (3)0.033 (2)0.005 (2)−0.001 (2)0.004 (2)
C70.036 (2)0.044 (3)0.024 (2)0.003 (2)−0.0019 (19)0.003 (2)
C80.029 (2)0.042 (3)0.034 (2)0.001 (2)−0.002 (2)0.002 (2)
C90.035 (2)0.052 (3)0.040 (3)−0.002 (2)−0.002 (2)−0.003 (2)
C100.030 (2)0.050 (3)0.027 (2)0.000 (2)0.000 (2)0.003 (2)
C110.034 (2)0.036 (3)0.028 (2)0.001 (2)−0.004 (2)0.001 (2)
C120.037 (2)0.038 (3)0.031 (2)−0.001 (2)−0.004 (2)0.001 (2)
C130.045 (3)0.043 (3)0.039 (3)0.007 (2)−0.006 (3)−0.004 (3)
C140.052 (3)0.041 (3)0.042 (3)−0.007 (2)−0.020 (3)0.005 (2)
C150.046 (3)0.043 (3)0.040 (3)−0.013 (2)−0.007 (2)0.003 (3)
C160.035 (2)0.046 (3)0.037 (3)−0.003 (2)0.001 (2)−0.001 (2)
C170.053 (3)0.069 (4)0.049 (3)0.000 (3)0.016 (2)−0.014 (3)
C180.048 (3)0.104 (5)0.063 (4)−0.023 (3)−0.009 (3)0.027 (4)

Geometric parameters (Å, °)

O1—C91.213 (5)C13—C141.390 (6)
O2—C121.365 (5)C14—C151.376 (6)
O2—C171.423 (5)C15—C161.374 (6)
O3—C151.376 (5)C2—H20.9300
O3—C181.411 (6)C3—H30.9300
C1—C21.385 (6)C4—H40.9300
C1—C61.380 (6)C5—H50.9300
C1—C91.470 (6)C7—H7A0.9700
C2—C31.382 (6)C7—H7B0.9700
C3—C41.379 (6)C10—H100.9300
C4—C51.399 (6)C13—H130.9300
C5—C61.383 (6)C14—H140.9300
C6—C71.507 (6)C16—H160.9300
C7—C81.506 (5)C17—H17A0.9600
C8—C91.507 (6)C17—H17B0.9600
C8—C101.339 (6)C17—H17C0.9600
C10—C111.452 (6)C18—H18A0.9600
C11—C121.408 (5)C18—H18B0.9600
C11—C161.406 (6)C18—H18C0.9600
C12—C131.386 (6)
O1···C7i3.259 (5)C14···H17Cviii2.8600
O2···C5ii3.384 (5)C15···H17Cviii2.9600
O2···C4ii3.351 (6)C15···H7Bvii3.0000
O1···H102.5200C16···H18C2.7500
O1···H22.9100C16···H7B3.0500
O1···H7Ai2.4700C16···H7A3.0200
O2···H102.3000C16···H7Bvii2.9900
O3···H18Biii2.6700C16···H18A2.7500
C3···C8iv3.572 (6)C17···H132.4900
C3···C9iv3.409 (6)C18···H162.5200
C4···C7iv3.508 (6)H2···O12.9100
C4···C8iv3.411 (6)H2···H18Ax2.5600
C4···O2v3.351 (6)H7A···C4vii2.9600
C4···C17v3.569 (6)H7A···C5vii3.0700
C5···C17v3.579 (6)H7A···C163.0200
C5···O2v3.384 (5)H7A···H162.2800
C6···C11iv3.476 (6)H7A···O1vi2.4700
C6···C10iv3.529 (6)H7B···C11iv2.9300
C7···C11iv3.552 (6)H7B···C12iv2.8800
C7···O1vi3.259 (5)H7B···C13iv2.8800
C7···C163.207 (6)H7B···C14iv2.9500
C7···C4vii3.508 (6)H7B···C15iv3.0000
C7···C12iv3.508 (6)H7B···C16iv2.9900
C8···C12iv3.536 (6)H7B···C163.0500
C8···C4vii3.411 (6)H7B···H162.3200
C8···C3vii3.572 (6)H10···O12.5200
C9···C3vii3.409 (6)H10···O22.3000
C10···C6vii3.529 (6)H13···C172.4900
C11···C7vii3.552 (6)H13···H17A2.3000
C11···C6vii3.476 (6)H13···H17C2.2700
C12···C8vii3.536 (6)H14···H18Cvii2.5800
C12···C7vii3.508 (6)H16···C72.5400
C13···C17viii3.512 (6)H16···C82.8500
C14···C17viii3.321 (6)H16···C182.5200
C15···C17viii3.597 (6)H16···H7A2.2800
C16···C73.207 (6)H16···H7B2.3200
C17···C5ii3.579 (6)H16···H18A2.2400
C17···C15ix3.597 (6)H16···H18C2.4000
C17···C4ii3.569 (6)H17A···C10vii2.8600
C17···C13ix3.512 (6)H17A···C132.7500
C17···C14ix3.321 (6)H17A···H132.3000
C4···H7Aiv2.9600H17B···C4ii2.9200
C4···H17Bv2.9200H17B···C5ii2.9200
C5···H7Aiv3.0700H17C···C132.7100
C5···H17Bv2.9200H17C···H132.2700
C7···H162.5400H17C···C13ix2.9800
C8···H162.8500H17C···C14ix2.8600
C10···H17Aiv2.8600H17C···C15ix2.9600
C11···H7Bvii2.9300H18A···C162.7500
C12···H7Bvii2.8800H18A···H162.2400
C13···H17A2.7500H18A···H2xi2.5600
C13···H7Bvii2.8800H18B···O3xii2.6700
C13···H17C2.7100H18C···C162.7500
C13···H17Cviii2.9800H18C···H14iv2.5800
C14···H7Bvii2.9500H18C···H162.4000
C12—O2—C17118.1 (3)C3—C2—H2121.00
C15—O3—C18117.0 (4)C2—C3—H3120.00
C2—C1—C6121.7 (4)C4—C3—H3120.00
C2—C1—C9128.5 (4)C3—C4—H4120.00
C6—C1—C9109.8 (4)C5—C4—H4120.00
C1—C2—C3118.1 (4)C4—C5—H5121.00
C2—C3—C4120.8 (4)C6—C5—H5121.00
C3—C4—C5120.8 (4)C6—C7—H7A111.00
C4—C5—C6118.3 (4)C6—C7—H7B111.00
C1—C6—C5120.2 (4)C8—C7—H7A111.00
C1—C6—C7112.1 (3)C8—C7—H7B111.00
C5—C6—C7127.7 (4)H7A—C7—H7B109.00
C6—C7—C8103.5 (3)C8—C10—H10115.00
C7—C8—C9108.4 (3)C11—C10—H10115.00
C7—C8—C10132.3 (4)C12—C13—H13120.00
C9—C8—C10119.3 (4)C14—C13—H13120.00
O1—C9—C1127.1 (4)C13—C14—H14120.00
O1—C9—C8126.6 (4)C15—C14—H14120.00
C1—C9—C8106.3 (3)C11—C16—H16119.00
C8—C10—C11130.6 (4)C15—C16—H16119.00
C10—C11—C12118.7 (4)O2—C17—H17A109.00
C10—C11—C16123.4 (4)O2—C17—H17B110.00
C12—C11—C16117.8 (4)O2—C17—H17C109.00
O2—C12—C11116.2 (3)H17A—C17—H17B110.00
O2—C12—C13123.2 (3)H17A—C17—H17C109.00
C11—C12—C13120.5 (4)H17B—C17—H17C109.00
C12—C13—C14119.7 (4)O3—C18—H18A109.00
C13—C14—C15120.6 (4)O3—C18—H18B109.00
O3—C15—C14115.7 (4)O3—C18—H18C109.00
O3—C15—C16124.4 (4)H18A—C18—H18B109.00
C14—C15—C16120.0 (4)H18A—C18—H18C109.00
C11—C16—C15121.3 (4)H18B—C18—H18C110.00
C1—C2—H2121.00
C17—O2—C12—C11−179.2 (3)C6—C7—C8—C10−179.9 (4)
C17—O2—C12—C131.8 (6)C7—C8—C9—O1179.0 (4)
C18—O3—C15—C14−163.3 (4)C7—C8—C9—C1−0.7 (4)
C18—O3—C15—C1616.5 (6)C10—C8—C9—O1−0.4 (6)
C6—C1—C2—C3−0.8 (6)C10—C8—C9—C1180.0 (4)
C9—C1—C2—C3178.0 (4)C7—C8—C10—C11−0.8 (8)
C2—C1—C6—C50.7 (6)C9—C8—C10—C11178.4 (4)
C2—C1—C6—C7179.4 (4)C8—C10—C11—C12179.3 (4)
C9—C1—C6—C5−178.3 (4)C8—C10—C11—C16−1.9 (7)
C9—C1—C6—C70.5 (5)C10—C11—C12—O2−2.4 (5)
C2—C1—C9—O11.6 (7)C10—C11—C12—C13176.6 (4)
C2—C1—C9—C8−178.8 (4)C16—C11—C12—O2178.8 (3)
C6—C1—C9—O1−179.5 (4)C16—C11—C12—C13−2.2 (6)
C6—C1—C9—C80.1 (5)C10—C11—C16—C15−177.4 (4)
C1—C2—C3—C40.4 (6)C12—C11—C16—C151.4 (6)
C2—C3—C4—C50.1 (7)O2—C12—C13—C14−178.9 (4)
C3—C4—C5—C6−0.3 (6)C11—C12—C13—C142.2 (6)
C4—C5—C6—C1−0.1 (6)C12—C13—C14—C15−1.3 (6)
C4—C5—C6—C7−178.7 (4)C13—C14—C15—O3−179.6 (4)
C1—C6—C7—C8−0.9 (4)C13—C14—C15—C160.5 (6)
C5—C6—C7—C8177.8 (4)O3—C15—C16—C11179.6 (4)
C6—C7—C8—C90.9 (4)C14—C15—C16—C11−0.6 (6)

Symmetry codes: (i) x−1/2, −y+1/2, z; (ii) x−1/2, −y+1/2, z+1; (iii) −x+2, −y+1, z+1/2; (iv) x, y, z−1; (v) x+1/2, −y+1/2, z−1; (vi) x+1/2, −y+1/2, z; (vii) x, y, z+1; (viii) −x+1, −y+1, z−1/2; (ix) −x+1, −y+1, z+1/2; (x) x−1/2, −y+1/2, z−1; (xi) x+1/2, −y+1/2, z+1; (xii) −x+2, −y+1, z−1/2.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C7—H7A···O1vi0.972.473.259 (5)139
C10—H10···O10.932.522.891 (5)104
C10—H10···O20.932.302.710 (5)106
C7—H7B···Cg1iv0.972.593.459 (4)150
C17—H17C···Cg1ix0.962.733.504 (4)138

Symmetry codes: (vi) x+1/2, −y+1/2, z; (iv) x, y, z−1; (ix) −x+1, −y+1, z+1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: JH2077).

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