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Acta Crystallogr Sect E Struct Rep Online. 2010 August 1; 66(Pt 8): o2133.
Published online 2010 July 31. doi:  10.1107/S1600536810029272
PMCID: PMC3007254

(2E)-3-(3,4-Dimeth­oxy­phen­yl)-1-(2,5-dimethyl­thio­phen-3-yl)prop-2-en-1-one

Abstract

The mol­ecule of the title compound, C17H18O3S, is essentially planar: the phenyl and thio­phene rings form a dihedral angle of 2.79 (10)° and they are inclined to the central propenone unit by 6.20 (15) and 4.78 (15)°, respectively. In the crystal, mol­ecules are connected into dimers via pairs of C—H(...)O inter­actions, generating R 2 2(14) motifs. π–π stacking inter­actions between the thio­phene rings also occur, with a centroid–centroid distance of 3.8062 (12) Å.

Related literature

For background to chalcones, their activity and applications, see: Bandgar et al. (2010 [triangle]); Deng et al. (2007 [triangle]); Liu et al. (2003 [triangle]); Verma et al. (2007 [triangle]). For graph-set notation, see: Bernstein et al. (1995 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o2133-scheme1.jpg

Experimental

Crystal data

  • C17H18O3S
  • M r = 302.37
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o2133-efi2.jpg
  • a = 9.1821 (6) Å
  • b = 8.3529 (5) Å
  • c = 20.3443 (13) Å
  • β = 94.624 (4)°
  • V = 1555.27 (17) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.22 mm−1
  • T = 296 K
  • 0.30 × 0.24 × 0.22 mm

Data collection

  • Bruker Kappa APEXII CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2005 [triangle]) T min = 0.868, T max = 0.965
  • 11371 measured reflections
  • 2791 independent reflections
  • 2182 reflections with I > 2σ(I)
  • R int = 0.025

Refinement

  • R[F 2 > 2σ(F 2)] = 0.036
  • wR(F 2) = 0.106
  • S = 1.07
  • 2791 reflections
  • 191 parameters
  • H-atom parameters constrained
  • Δρmax = 0.15 e Å−3
  • Δρmin = −0.24 e Å−3

Data collection: APEX2 (Bruker, 2009 [triangle]); cell refinement: SAINT (Bruker, 2009 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]) and PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]) and PLATON.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks text, I. DOI: 10.1107/S1600536810029272/gk2297sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810029272/gk2297Isup2.hkl

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

Acknowledgments

The authors would like to thank the Chemistry Department, King Abdul Aziz University, Jeddah, Saudi Arabia for providing research facilities and for financial support of this work via grant No. 3–045/430.

supplementary crystallographic information

Comment

α,β- Unsaturated ketones are a family of bicyclic flavonoids, defined by the presence of two benzene rings joined by a three carbon bridge. Many natural or synthetic chalcones, as well as chalcone glucosides and dimeric chalcones, were found to show diverse pharmacological effects, such as antimicrobial activity (Bandgar et al., 2010), anti-HIV-1 protease activity (Deng et al., 2007) and antileishmanial activity (Liu et al., 2003). In addition, chalcones were used as important intermediates for the total synthesis of some natural products (Verma et al., 2007). On the bases of these aspects, we herein report the synthesis and crystal structure of title compound (Fig. 1).

In the title compound, the group A (C1—C6/O1/O2) of 3,4-dimethoxyphenyl, the central group B (C9—C11/O3) and group C (C12—C17/S1) of 2,5-dimethylthiophen-3-yl moiety are planar. The dihedral angle between A/B, A/C and B/C is 6.58 (14), 3.19 (8) and 4.78 (15)°, respectively. The C-atoms, C7 and C8 of methoxy groups are at a distance of -0.1564 (27) and -0.0979 (32) Å from the mean square plane of the group A. The title compound consists of dimers which are formed due to C—H···O type of intermolecular H-bonding (Table 1, Fig. 2) and complete R22(14) ring motif (Bernstein et al., 1995). The π···π stacking interactions between their thiophene rings is also present, with the centroid-to centroid distance of 3.8062 (12) Å [symmetry code: - x, 1 - y, - z].

Experimental

A solution of 3-acetyl-2,5-dimethythiophene (0.38 g, 2.5 mmol) and 3,4-dimethoxybenzaldehyde (0.41 g, 2.5 mmol) in ethanolic solution of NaOH (3.0 g in 10 ml of methanol) was stirred for 16 h at room temperature. The solution was poured into ice cold water of pH = 2 (pH adjusted by HCl). The solid was separated and dissolved in CH2Cl2, washed with saturated solution of NaHCO3 and evaporated to dryness. The residual was recrystallized from methanol/chloroform to affoard light yellow prisms . Yield: 76%; m.p. 387–388 K. IR (KBr) \vmax cm-1: 2909 (C—H), 1647 (C═O), 1583(C═C).

Refinement

The H-atoms were positioned geometrically (C–H = 0.93–0.96 Å) and refined as riding with Uiso(H) = xUeq(C), where x = 1.5 for methyl and x = 1.2 for aryl H-atoms. One of the methyl group is disordered over two positions related by a rotation of 60° around the C-C bond.

Figures

Fig. 1.
View of the title compound with the atom numbering scheme. The displacement ellipsoids are drawn at the 30% probability level. H-atoms are shown as small spheres of arbitrary radii.
Fig. 2.
The dimers with R22(14) ring motif.

Crystal data

C17H18O3SF(000) = 640
Mr = 302.37Dx = 1.291 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 2182 reflections
a = 9.1821 (6) Åθ = 2.5–25.3°
b = 8.3529 (5) ŵ = 0.22 mm1
c = 20.3443 (13) ÅT = 296 K
β = 94.624 (4)°Prism, yellow
V = 1555.27 (17) Å30.30 × 0.24 × 0.22 mm
Z = 4

Data collection

Bruker KAPPA APEXII CCD diffractometer2791 independent reflections
Radiation source: fine-focus sealed tube2182 reflections with I > 2σ(I)
graphiteRint = 0.025
Detector resolution: 8.10 pixels mm-1θmax = 25.3°, θmin = 2.5°
ω scansh = −10→11
Absorption correction: multi-scan (SADABS; Bruker, 2005)k = −9→10
Tmin = 0.868, Tmax = 0.965l = −24→24
11371 measured reflections

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)] = 0.036Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.106H-atom parameters constrained
S = 1.07w = 1/[σ2(Fo2) + (0.0462P)2 + 0.374P] where P = (Fo2 + 2Fc2)/3
2791 reflections(Δ/σ)max < 0.001
191 parametersΔρmax = 0.15 e Å3
0 restraintsΔρmin = −0.24 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 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*/UeqOcc. (<1)
S1−0.23565 (6)0.41751 (7)−0.05399 (3)0.0660 (2)
O10.29637 (14)−0.19408 (15)0.29377 (6)0.0576 (4)
O20.54659 (15)−0.32480 (16)0.28650 (7)0.0659 (5)
O30.20712 (19)0.1767 (2)−0.04839 (7)0.0981 (7)
C10.37251 (18)−0.05442 (19)0.12728 (8)0.0467 (6)
C20.29878 (18)−0.07466 (19)0.18470 (8)0.0450 (5)
C30.36019 (19)−0.16436 (19)0.23649 (8)0.0451 (5)
C40.49784 (19)−0.2356 (2)0.23254 (9)0.0490 (6)
C50.57073 (19)−0.2145 (2)0.17692 (10)0.0551 (6)
C60.50821 (19)−0.1245 (2)0.12462 (9)0.0541 (6)
C70.1508 (2)−0.1415 (3)0.29816 (9)0.0614 (7)
C80.6814 (3)−0.4081 (3)0.28383 (12)0.0842 (9)
C90.3079 (2)0.0318 (2)0.06976 (9)0.0543 (6)
C100.1823 (2)0.1089 (2)0.06199 (8)0.0518 (6)
C110.1314 (2)0.1829 (2)−0.00184 (9)0.0582 (7)
C12−0.0124 (2)0.2618 (2)−0.00808 (8)0.0512 (6)
C13−0.1133 (2)0.2654 (3)0.04167 (9)0.0626 (7)
C14−0.2388 (2)0.3431 (3)0.02449 (10)0.0645 (7)
C15−0.0661 (2)0.3419 (2)−0.06373 (9)0.0534 (6)
C160.00200 (19)0.3678 (3)−0.12765 (8)0.0764 (9)
C17−0.3685 (2)0.3698 (3)0.06374 (9)0.0992 (11)
H20.20796−0.027120.187670.0540*
H50.66227−0.260530.174230.0661*
H60.55856−0.111260.087120.0649*
H7A0.08903−0.186920.262640.0921*
H7B0.14723−0.026820.295290.0921*
H7C0.11750−0.175100.339510.0921*
H8A0.75919−0.332350.280760.1263*
H8B0.67593−0.476910.245910.1263*
H8C0.69998−0.471290.323040.1263*
H90.363150.032520.033400.0652*
H100.124560.116800.097360.0621*
H13−0.093720.217710.082740.0751*
H16A0.018480.26624−0.147830.1146*0.800
H16B0.093420.42280−0.119230.1146*0.800
H16C−0.062430.43103−0.156700.1146*0.800
H17A−0.353550.315120.105250.1488*
H17B−0.454840.328910.039680.1488*
H17C−0.380040.482310.071360.1488*
H16D−0.069130.34716−0.163860.1146*0.200
H16E0.083320.29641−0.130030.1146*0.200
H16F0.035290.47650−0.129870.1146*0.200

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
S10.0546 (3)0.0741 (4)0.0675 (3)0.0037 (3)−0.0054 (2)−0.0005 (3)
O10.0578 (8)0.0640 (8)0.0522 (7)0.0112 (6)0.0117 (6)0.0113 (6)
O20.0603 (8)0.0686 (9)0.0679 (9)0.0191 (7)−0.0009 (7)0.0068 (7)
O30.0874 (11)0.1509 (16)0.0607 (9)0.0547 (11)0.0350 (8)0.0337 (10)
C10.0462 (10)0.0443 (9)0.0504 (10)−0.0022 (7)0.0085 (8)−0.0028 (7)
C20.0419 (9)0.0426 (9)0.0512 (10)0.0027 (7)0.0080 (7)−0.0023 (7)
C30.0468 (10)0.0402 (9)0.0489 (9)−0.0008 (7)0.0068 (8)−0.0029 (7)
C40.0462 (10)0.0434 (9)0.0565 (10)0.0007 (8)−0.0014 (8)−0.0028 (8)
C50.0390 (10)0.0560 (11)0.0706 (12)0.0033 (8)0.0069 (9)−0.0077 (9)
C60.0475 (10)0.0590 (11)0.0575 (11)−0.0019 (8)0.0142 (8)−0.0030 (9)
C70.0589 (12)0.0756 (13)0.0514 (10)0.0145 (10)0.0152 (9)0.0050 (9)
C80.0675 (14)0.0900 (17)0.0931 (17)0.0315 (13)−0.0065 (12)0.0054 (13)
C90.0573 (11)0.0587 (11)0.0490 (10)0.0026 (9)0.0164 (8)0.0015 (8)
C100.0536 (11)0.0596 (11)0.0433 (9)0.0034 (9)0.0117 (8)−0.0026 (8)
C110.0617 (12)0.0680 (12)0.0466 (10)0.0098 (9)0.0146 (9)0.0029 (9)
C120.0527 (10)0.0548 (10)0.0465 (10)0.0003 (8)0.0061 (8)−0.0044 (8)
C130.0606 (12)0.0760 (13)0.0525 (11)0.0089 (10)0.0131 (9)0.0037 (9)
C140.0541 (12)0.0737 (13)0.0666 (12)0.0029 (10)0.0104 (9)−0.0047 (10)
C150.0549 (11)0.0563 (10)0.0484 (10)−0.0049 (8)0.0006 (8)−0.0058 (8)
C160.0811 (16)0.0956 (16)0.0524 (12)0.0066 (13)0.0046 (11)0.0097 (11)
C170.0693 (16)0.134 (2)0.0976 (19)0.0252 (16)0.0270 (14)0.0061 (17)

Geometric parameters (Å, °)

S1—C141.716 (2)C2—H20.9300
S1—C151.7063 (19)C5—H50.9300
O1—C31.369 (2)C6—H60.9300
O1—C71.417 (2)C7—H7A0.9600
O2—C41.372 (2)C7—H7B0.9600
O2—C81.425 (3)C7—H7C0.9600
O3—C111.220 (2)C8—H8A0.9600
C1—C21.407 (2)C8—H8B0.9600
C1—C61.382 (2)C8—H8C0.9600
C1—C91.459 (2)C9—H90.9300
C2—C31.376 (2)C10—H100.9300
C3—C41.405 (2)C13—H130.9300
C4—C51.372 (3)C16—H16A0.9600
C5—C61.389 (3)C16—H16B0.9600
C9—C101.319 (3)C16—H16C0.9600
C10—C111.480 (2)C16—H16D0.9600
C11—C121.472 (3)C16—H16E0.9600
C12—C131.427 (3)C16—H16F0.9600
C12—C151.372 (2)C17—H17A0.9600
C13—C141.344 (3)C17—H17B0.9600
C14—C171.503 (3)C17—H17C0.9600
C15—C161.503 (2)
S1···C1i3.5635 (17)H2···C72.5400
S1···C11ii3.6293 (18)H2···C102.7900
S1···C12ii3.6734 (18)H2···H7A2.3600
S1···C7iii3.624 (2)H2···H7B2.3000
O1···O22.5588 (19)H2···H102.2800
O1···C2iv3.335 (2)H2···O1vii2.8100
O1···C10iv3.356 (2)H5···C82.5400
O2···O12.5588 (19)H5···H8A2.3500
O3···C6v3.175 (2)H5···H8B2.3200
O3···C162.865 (3)H5···H16Ev2.5900
O1···H16Cvi2.7000H6···H92.3500
O1···H10iv2.7700H6···O3v2.4100
O1···H2iv2.8100H7A···C22.7600
O2···H13iv2.6800H7A···H22.3600
O2···H7Biv2.8800H7A···H16Ai2.5500
O3···H92.4300H7A···H16Di2.4100
O3···H16B2.6700H7B···C22.7700
O3···H16E2.1800H7B···H22.3000
O3···H16A2.6600H7B···O2vii2.8800
O3···H6v2.4100H7B···C3vii3.1000
C1···S1i3.5635 (17)H7B···C4vii2.8100
C2···O1vii3.335 (2)H8A···C52.8000
C5···C8viii3.475 (3)H8A···H52.3500
C6···O3v3.175 (2)H8B···C52.7400
C7···S1vi3.624 (2)H8B···H52.3200
C8···C5ix3.475 (3)H8C···C5ix2.9300
C10···C12i3.598 (2)H8C···C6ix3.0800
C10···O1vii3.356 (2)H9···O32.4300
C11···S1ii3.6293 (18)H9···H62.3500
C12···C10i3.598 (2)H10···C22.8000
C12···S1ii3.6734 (18)H10···C132.6800
C16···O32.865 (3)H10···H22.2800
C2···H7B2.7700H10···H132.1700
C2···H102.8000H10···O1vii2.7700
C2···H7A2.7600H13···C102.7600
C3···H7Biv3.1000H13···H102.1700
C3···H16Cvi2.9600H13···H17A2.6000
C4···H7Biv2.8100H13···O2vii2.6800
C5···H8Cviii2.9300H13···C8vii3.0800
C5···H8A2.8000H16A···O32.6600
C5···H8B2.7400H16A···H7Ai2.5500
C6···H8Cviii3.0800H16B···O32.6700
C7···H22.5400H16B···C13ii3.0400
C8···H13iv3.0800H16B···C14ii2.9800
C8···H52.5400H16C···O1iii2.7000
C10···H132.7600H16C···C3iii2.9600
C10···H22.7900H16D···H7Ai2.4100
C11···H16E2.7800H16E···C112.7800
C13···H102.6800H16E···O32.1800
C13···H16Fii2.8600H16E···H5v2.5900
C13···H16Bii3.0400H16F···C13ii2.8600
C14···H16Bii2.9800H17A···H132.6000
C14—S1—C1593.32 (9)O1—C7—H7A109.00
C3—O1—C7117.93 (14)O1—C7—H7B109.00
C4—O2—C8117.60 (16)O1—C7—H7C109.00
C2—C1—C6118.52 (15)H7A—C7—H7B109.00
C2—C1—C9122.25 (15)H7A—C7—H7C109.00
C6—C1—C9119.17 (15)H7B—C7—H7C109.00
C1—C2—C3120.42 (15)O2—C8—H8A110.00
O1—C3—C2125.00 (15)O2—C8—H8B109.00
O1—C3—C4114.88 (15)O2—C8—H8C109.00
C2—C3—C4120.12 (16)H8A—C8—H8B109.00
O2—C4—C3114.92 (15)H8A—C8—H8C109.00
O2—C4—C5125.49 (16)H8B—C8—H8C109.00
C3—C4—C5119.59 (16)C1—C9—H9115.00
C4—C5—C6120.17 (16)C10—C9—H9115.00
C1—C6—C5121.18 (16)C9—C10—H10119.00
C1—C9—C10129.21 (17)C11—C10—H10119.00
C9—C10—C11121.36 (16)C12—C13—H13123.00
O3—C11—C10120.27 (17)C14—C13—H13123.00
O3—C11—C12121.02 (17)C15—C16—H16A109.00
C10—C11—C12118.71 (15)C15—C16—H16B109.00
C11—C12—C13125.28 (16)C15—C16—H16C109.00
C11—C12—C15123.34 (16)C15—C16—H16D109.00
C13—C12—C15111.37 (17)C15—C16—H16E109.00
C12—C13—C14114.71 (18)C15—C16—H16F109.00
S1—C14—C13109.79 (15)H16A—C16—H16B109.00
S1—C14—C17120.94 (15)H16A—C16—H16C109.00
C13—C14—C17129.27 (19)H16B—C16—H16C109.00
S1—C15—C12110.81 (14)H16D—C16—H16E109.00
S1—C15—C16119.62 (14)H16D—C16—H16F109.00
C12—C15—C16129.57 (17)H16E—C16—H16F109.00
C1—C2—H2120.00C14—C17—H17A109.00
C3—C2—H2120.00C14—C17—H17B109.00
C4—C5—H5120.00C14—C17—H17C109.00
C6—C5—H5120.00H17A—C17—H17B109.00
C1—C6—H6119.00H17A—C17—H17C109.00
C5—C6—H6119.00H17B—C17—H17C109.00
C15—S1—C14—C130.60 (19)C2—C3—C4—C50.3 (3)
C15—S1—C14—C17−179.89 (19)O2—C4—C5—C6178.31 (16)
C14—S1—C15—C12−0.23 (15)C3—C4—C5—C6−0.6 (3)
C14—S1—C15—C16179.43 (17)C4—C5—C6—C10.1 (3)
C7—O1—C3—C26.1 (2)C1—C9—C10—C11−176.81 (16)
C7—O1—C3—C4−172.97 (16)C9—C10—C11—O3−1.6 (3)
C8—O2—C4—C3176.26 (17)C9—C10—C11—C12177.63 (16)
C8—O2—C4—C5−2.7 (3)O3—C11—C12—C13175.23 (19)
C6—C1—C2—C3−0.9 (2)O3—C11—C12—C15−4.6 (3)
C9—C1—C2—C3176.38 (16)C10—C11—C12—C13−4.0 (3)
C2—C1—C6—C50.7 (2)C10—C11—C12—C15176.11 (16)
C9—C1—C6—C5−176.74 (16)C11—C12—C13—C14−179.21 (19)
C2—C1—C9—C103.9 (3)C15—C12—C13—C140.7 (3)
C6—C1—C9—C10−178.80 (18)C11—C12—C15—S1179.70 (14)
C1—C2—C3—O1−178.57 (15)C11—C12—C15—C160.1 (3)
C1—C2—C3—C40.5 (2)C13—C12—C15—S1−0.2 (2)
O1—C3—C4—O20.4 (2)C13—C12—C15—C16−179.81 (19)
O1—C3—C4—C5179.43 (15)C12—C13—C14—S1−0.8 (3)
C2—C3—C4—O2−178.71 (15)C12—C13—C14—C17179.7 (2)

Symmetry codes: (i) −x, −y, −z; (ii) −x, −y+1, −z; (iii) x−1/2, −y+1/2, z−1/2; (iv) −x+1/2, y−1/2, −z+1/2; (v) −x+1, −y, −z; (vi) x+1/2, −y+1/2, z+1/2; (vii) −x+1/2, y+1/2, −z+1/2; (viii) −x+3/2, y+1/2, −z+1/2; (ix) −x+3/2, y−1/2, −z+1/2.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C6—H6···O3v0.932.413.175 (2)139

Symmetry codes: (v) −x+1, −y, −z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: GK2297).

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