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Acta Crystallogr Sect E Struct Rep Online. 2008 August 1; 64(Pt 8): o1510–o1511.
Published online 2008 July 16. doi:  10.1107/S1600536808021375
PMCID: PMC2962137

(E)-1-(2-Thien­yl)-3-(2,4,5-trimethoxy­phen­yl)prop-2-en-1-one

Abstract

In the title mol­ecule, C16H16O4S, the enone fragment, thio­phene ring and benzene ring are individually essentially planar. The thio­phene ring is disordered over two sites, corresponding to a rotation of approximately 180° about the single C—C bond to which it is attached. The approximate ratio of occupancies for the major and minor components is 0.872 (2):0.128 (2). The major component of the thio­phene ring and the benzene ring are twisted from each other by 13.92 (19)°. An intra­molecular C—H(...)O hydrogen bond generates an S(5)S(5) ring motif. The crystal structure is stabilized by inter­molecular C—H(...)O hydrogen-bonding inter­actions. In addition, a π–π stacking inter­action, with a centroid–centroid distance of 3.852 (2) Å, and short S(...)O [2.9378 (12) Å] and O(...)O [2.5811 (16) Å] contacts are observed.

Related literature

For related literature, see: Chantrapromma et al. (2005 [triangle], 2006 [triangle]); Fun et al. (2006 [triangle]); Patil, Fun et al. (2007 [triangle]); Patil, Dharmaprakash et al.(2007 [triangle]). For bond-length data, see: Allen et al. (1987 [triangle]); Patil et al. (2006 [triangle]). For graph-set analysis of hydrogen bonding, see: Bernstein et al. (1995 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-64-o1510-scheme1.jpg

Experimental

Crystal data

  • C16H16O4S
  • M r = 304.35
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-o1510-efi1.jpg
  • a = 7.5391 (1) Å
  • b = 7.9225 (1) Å
  • c = 24.3399 (3) Å
  • β = 97.021 (1)°
  • V = 1442.88 (3) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.24 mm−1
  • T = 100.0 (1) K
  • 0.25 × 0.22 × 0.14 mm

Data collection

  • Bruker SMART APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2005 [triangle]) T min = 0.942, T max = 0.967
  • 33027 measured reflections
  • 4256 independent reflections
  • 3174 reflections with I > 2σ(I)
  • R int = 0.063

Refinement

  • R[F 2 > 2σ(F 2)] = 0.045
  • wR(F 2) = 0.120
  • S = 1.07
  • 4256 reflections
  • 211 parameters
  • 120 restraints
  • H-atom parameters constrained
  • Δρmax = 0.41 e Å−3
  • Δρmin = −0.22 e Å−3

Data collection: APEX2 (Bruker, 2005 [triangle]); cell refinement: APEX2; data reduction: SAINT (Bruker, 2005 [triangle]); 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 and PLATON (Spek, 2003 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808021375/lh2658sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808021375/lh2658Isup2.hkl

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

Acknowledgments

HKF and SRJ thank the Malaysian Government and Universiti Sains Malaysia for the Science Fund grant No. 305/PFIZIK/613312. SRJ thanks Universiti Sains Malaysia for a post-doctoral research fellowship. This work was supported by the Department of Science and Technology (DST), Government of India (grant No. SR/S2/LOP-17/2006).

supplementary crystallographic information

Comment

The title compound (I) has been synthesized as part of our crystallographic studies on nonlinear optical materials (Chantrapromma et al., 2005, 2006; Fun et al., 2006; Patil, Fun et al., 2007; Patil, Dharmaprakash et al., 2007). We report herein the crystal structure of the title compound, (I).

In the title molecular structure (I), the thiophene ring is disordered over two sites (atoms of the minor occupancy component are labelled with the suffix X), corresponding to a rotation of approximately 180° about the C4—C5 bond. The bond lengths and bond angles are found to have normal values (Allen et al., 1987) and agree with a related structure (Patil et al., 2006) with the execption of some parameters of the thiophene ring, which are probably a consequence of the disorder. The benzene and thiophene rings are individually planar, with maximum deviations of 0.019 (2) Å for atom C12 and -0.074 (2)Å for atom C1X. The molecule is twisted about the C7—C8 bond with a dihedral angle of 13.93 (19)° between the benzene ring and S1/C1—C4 [15.9 (19)° for S1X/C1X—C3X].

Intramolecular hydrogen bond C—H···O generates ring motif S(5)S(5) (Bernstein et al., 1995). The crystal packing is stabilized by intra and intermolecular C—H···O interactions. π—π interactions between the S1/C1—C4 (centroid Cg1) and C8—C13 (centroid Cg3) rings [Cg1···Cg3i=3.852 (2) Å] [symmetry code: (i) -x,-y,-z] together with S···O=2.9378 (12)Å and O···O=2.5811 (16)Å short contacts are observed.

Experimental

2,4,5-trimethoxybenzaldehyde (0.01 mol, 1.96 g m) in ethanol (30 ml) was mixed with 2-acetylthiophene (0.01 mol, 1.07 ml) in 30 ml ethanol and the mixture was treated with 10 ml of 10% sodium hydroxide solution and stirred at room temperature for 8 h. The precipitate obtained was poured into ice-cold water (500 ml) and left to stand for 5 h. The resulting crude solid was filtered, dried and recrystallized from N, N-dimethylformamide (DMF) by slow evaporation.

Refinement

H atoms were positioned geometrically [C—H = 0.93Å; and CH3=0.96 Å] and refined using a riding model, with Uiso(H) = 1.2Ueq(C) and 1.5eq(Cmethyl). A rotating group model was used for the methyl groups. The ratio of the refined occupancies for the major and minor components of the disordered thiophene ring is 0.872 (2):0.128 (2). Similarity and rigid-bond restraints were applied to the disordered atoms.

Figures

Fig. 1.
The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atom numbering scheme. Open bonds indicate the minor disorder component. Dashed lines indicate hydrogen bonds.
Fig. 2.
The crystal packing of the major component of the title compound,viewed along the c axis. Hydrogen bonds are shown as dashed lines.
Fig. 3.
The crystal packing of the minor component of the title compound, viewed along the c axis. Hydrogen bonds are shown as dashed lines.

Crystal data

C16H16O4SF000 = 640
Mr = 304.35Dx = 1.401 Mg m3
Monoclinic, P21/cMo Kα radiation λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 4291 reflections
a = 7.53910 (10) Åθ = 2.7–28.4º
b = 7.92250 (10) ŵ = 0.24 mm1
c = 24.3399 (3) ÅT = 100.0 (1) K
β = 97.0210 (10)ºBlock, yellow
V = 1442.88 (3) Å30.25 × 0.22 × 0.14 mm
Z = 4

Data collection

Bruker SMART APEXII CCD area-detector diffractometer4256 independent reflections
Radiation source: fine-focus sealed tube3174 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.063
T = 100.0(1) Kθmax = 30.1º
[var phi] and ω scansθmin = 1.7º
Absorption correction: multi-scan(SADABS; Bruker, 2005)h = −10→10
Tmin = 0.942, Tmax = 0.967k = −11→10
33027 measured reflectionsl = −34→34

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.046H-atom parameters constrained
wR(F2) = 0.120  w = 1/[σ2(Fo2) + (0.0532P)2 + 0.4695P] where P = (Fo2 + 2Fc2)/3
S = 1.07(Δ/σ)max < 0.001
4256 reflectionsΔρmax = 0.41 e Å3
211 parametersΔρmin = −0.22 e Å3
120 restraintsExtinction correction: none
Primary atom site location: structure-invariant direct methods

Special details

Experimental. The data was collected with the Oxford Cyrosystem Cobra low-temperature attachment.
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*/UeqOcc. (<1)
O10.21432 (18)−0.07151 (14)0.09237 (4)0.0317 (3)
O20.17726 (15)0.05965 (14)−0.21790 (4)0.0241 (2)
O30.32216 (15)−0.21704 (14)−0.24632 (4)0.0245 (2)
O40.38751 (16)−0.41134 (14)−0.05568 (4)0.0256 (3)
C40.1783 (2)0.22121 (18)0.08330 (6)0.0207 (3)
S10.17822 (8)0.24407 (6)0.153399 (18)0.02221 (15)0.870 (2)
C10.1475 (5)0.4570 (4)0.14728 (11)0.0232 (6)0.870 (2)
H1A0.14130.52860.17730.028*0.870 (2)
C20.1330 (9)0.5112 (4)0.09346 (15)0.0270 (8)0.870 (2)
H2A0.11190.62230.08220.032*0.870 (2)
C30.1544 (10)0.3750 (7)0.05759 (18)0.0335 (12)0.870 (2)
H3A0.15260.38830.01960.040*0.870 (2)
S1X0.1377 (15)0.3871 (9)0.0437 (3)0.0239 (13)0.130 (2)
C1X0.145 (7)0.511 (3)0.1014 (8)0.036 (8)*0.130 (2)
H1XA0.14810.62810.10030.043*0.130 (2)
C2X0.147 (4)0.421 (2)0.1494 (9)0.027 (6)*0.130 (2)
H2XA0.12960.46350.18390.032*0.130 (2)
C3X0.180 (3)0.253 (2)0.1369 (6)0.0335 (12)0.130 (2)
H3XA0.20080.16990.16400.040*0.130 (2)
C50.2048 (2)0.05105 (19)0.06134 (6)0.0227 (3)
C60.2186 (2)0.03664 (19)0.00174 (6)0.0237 (3)
H6A0.19750.1315−0.02060.028*
C70.2608 (2)−0.10914 (19)−0.02109 (6)0.0224 (3)
H7A0.2816−0.20090.00270.027*
C80.2776 (2)−0.13959 (18)−0.07931 (6)0.0203 (3)
C90.3410 (2)−0.29444 (19)−0.09632 (6)0.0205 (3)
C100.3580 (2)−0.32485 (19)−0.15198 (6)0.0210 (3)
H10A0.4022−0.4277−0.16270.025*
C110.3088 (2)−0.20143 (19)−0.19118 (6)0.0200 (3)
C120.2371 (2)−0.04789 (19)−0.17534 (6)0.0204 (3)
C130.2256 (2)−0.01779 (19)−0.12019 (6)0.0211 (3)
H13A0.18230.0857−0.10970.025*
C140.0920 (2)0.2100 (2)−0.20310 (6)0.0280 (4)
H14A0.05590.2753−0.23580.042*
H14B0.17360.2746−0.17800.042*
H14C−0.01130.1815−0.18550.042*
C150.3832 (2)−0.3757 (2)−0.26506 (7)0.0305 (4)
H15A0.3869−0.3710−0.30430.046*
H15B0.3028−0.4635−0.25680.046*
H15C0.5007−0.3988−0.24670.046*
C160.4083 (2)−0.5814 (2)−0.07198 (7)0.0278 (3)
H16B0.4405−0.6498−0.03970.042*
H16C0.5006−0.5879−0.09580.042*
H16D0.2979−0.6215−0.09140.042*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0575 (8)0.0197 (6)0.0187 (5)0.0009 (5)0.0076 (5)0.0019 (4)
O20.0354 (6)0.0222 (5)0.0150 (5)0.0045 (5)0.0046 (4)0.0008 (4)
O30.0346 (6)0.0249 (6)0.0151 (5)0.0023 (5)0.0077 (4)−0.0036 (4)
O40.0389 (6)0.0205 (5)0.0167 (5)0.0049 (5)0.0009 (4)−0.0005 (4)
C40.0270 (7)0.0213 (7)0.0144 (6)−0.0020 (6)0.0050 (5)−0.0017 (5)
S10.0312 (3)0.0219 (2)0.0139 (2)−0.00063 (17)0.0044 (2)−0.00192 (18)
C10.0330 (13)0.0168 (12)0.0206 (11)0.0017 (12)0.0061 (7)−0.0042 (9)
C20.0443 (19)0.0168 (11)0.0206 (11)−0.0016 (8)0.0072 (15)−0.0015 (7)
C30.0466 (19)0.0352 (17)0.020 (2)−0.0016 (12)0.0106 (17)−0.0004 (13)
S1X0.041 (3)0.0111 (18)0.022 (3)−0.0021 (16)0.014 (2)−0.0060 (17)
C3X0.0466 (19)0.0352 (17)0.020 (2)−0.0016 (12)0.0106 (17)−0.0004 (13)
C50.0312 (8)0.0208 (7)0.0167 (7)−0.0011 (6)0.0048 (6)−0.0011 (5)
C60.0353 (8)0.0201 (7)0.0164 (7)−0.0018 (6)0.0058 (6)0.0006 (5)
C70.0277 (8)0.0234 (7)0.0163 (6)−0.0010 (6)0.0025 (6)−0.0002 (5)
C80.0269 (7)0.0190 (7)0.0153 (6)−0.0026 (6)0.0042 (5)−0.0023 (5)
C90.0242 (7)0.0203 (7)0.0166 (7)−0.0006 (6)0.0005 (5)−0.0002 (5)
C100.0256 (7)0.0207 (7)0.0172 (7)0.0005 (6)0.0042 (5)−0.0033 (5)
C110.0228 (7)0.0234 (7)0.0140 (6)−0.0023 (6)0.0037 (5)−0.0021 (5)
C120.0246 (7)0.0207 (7)0.0163 (6)−0.0017 (6)0.0039 (5)0.0006 (5)
C130.0286 (8)0.0184 (7)0.0169 (7)−0.0009 (6)0.0047 (6)−0.0022 (5)
C140.0395 (9)0.0243 (8)0.0201 (7)0.0073 (7)0.0030 (6)0.0005 (6)
C150.0429 (10)0.0298 (9)0.0196 (7)0.0075 (7)0.0064 (7)−0.0071 (6)
C160.0396 (9)0.0207 (7)0.0221 (7)0.0019 (7)−0.0002 (6)−0.0007 (6)

Geometric parameters (Å, °)

O1—C51.2268 (18)C3X—H3XA0.9300
O2—C121.3741 (17)C5—C61.472 (2)
O2—C141.4206 (19)C6—C71.337 (2)
O3—C111.3637 (17)C6—H6A0.9300
O3—C151.4319 (19)C7—C81.4582 (19)
O4—C91.3692 (17)C7—H7A0.9300
O4—C161.4182 (18)C8—C91.398 (2)
C4—C3X1.328 (13)C8—C131.407 (2)
C4—C31.371 (5)C9—C101.3972 (19)
C4—C51.473 (2)C10—C111.385 (2)
C4—S1X1.636 (7)C10—H10A0.9300
C4—S11.7158 (15)C11—C121.404 (2)
S1—C11.707 (3)C12—C131.376 (2)
C1—C21.370 (4)C13—H13A0.9300
C1—H1A0.9300C14—H14A0.9600
C2—C31.410 (6)C14—H14B0.9600
C2—H2A0.9300C14—H14C0.9600
C3—H3A0.9300C15—H15A0.9600
S1X—C1X1.708 (18)C15—H15B0.9600
C1X—C2X1.368 (17)C15—H15C0.9600
C1X—H1XA0.9300C16—H16B0.9600
C2X—C3X1.391 (17)C16—H16C0.9600
C2X—H2XA0.9300C16—H16D0.9600
C12—O2—C14116.47 (11)C6—C7—H7A116.6
C11—O3—C15117.29 (12)C8—C7—H7A116.6
C9—O4—C16117.89 (11)C9—C8—C13117.93 (13)
C3X—C4—C3105.4 (8)C9—C8—C7120.43 (13)
C3X—C4—C5123.0 (8)C13—C8—C7121.61 (13)
C3—C4—C5131.6 (2)O4—C9—C10122.55 (13)
C3X—C4—S1X113.9 (8)O4—C9—C8116.52 (12)
C5—C4—S1X123.0 (3)C10—C9—C8120.92 (13)
C3—C4—S1110.1 (2)C11—C10—C9119.84 (14)
C5—C4—S1118.30 (11)C11—C10—H10A120.1
S1X—C4—S1118.6 (3)C9—C10—H10A120.1
C1—S1—C491.96 (10)O3—C11—C10124.62 (13)
C2—C1—S1112.8 (2)O3—C11—C12115.23 (13)
C2—C1—H1A123.6C10—C11—C12120.15 (13)
S1—C1—H1A123.6O2—C12—C13125.01 (13)
C1—C2—C3110.5 (3)O2—C12—C11115.59 (12)
C1—C2—H2A124.7C13—C12—C11119.36 (13)
C3—C2—H2A124.7C12—C13—C8121.70 (14)
C4—C3—C2114.6 (3)C12—C13—H13A119.2
C4—C3—H3A122.7C8—C13—H13A119.2
C2—C3—H3A122.7O2—C14—H14A109.5
C4—S1X—C1X89.5 (9)O2—C14—H14B109.5
C2X—C1X—S1X113.4 (16)H14A—C14—H14B109.5
C2X—C1X—H1XA123.3O2—C14—H14C109.5
S1X—C1X—H1XA123.3H14A—C14—H14C109.5
C1X—C2X—C3X107.3 (17)H14B—C14—H14C109.5
C1X—C2X—H2XA126.4O3—C15—H15A109.5
C3X—C2X—H2XA126.4O3—C15—H15B109.5
C4—C3X—C2X114.5 (14)H15A—C15—H15B109.5
C4—C3X—H3XA122.8O3—C15—H15C109.5
C2X—C3X—H3XA122.8H15A—C15—H15C109.5
O1—C5—C6122.66 (14)H15B—C15—H15C109.5
O1—C5—C4120.09 (13)O4—C16—H16B109.5
C6—C5—C4117.25 (13)O4—C16—H16C109.5
C7—C6—C5121.74 (14)H16B—C16—H16C109.5
C7—C6—H6A119.1O4—C16—H16D109.5
C5—C6—H6A119.1H16B—C16—H16D109.5
C6—C7—C8126.89 (14)H16C—C16—H16D109.5
C3X—C4—S1—C113 (12)S1—C4—C5—C6−175.26 (11)
C3—C4—S1—C1−0.2 (4)O1—C5—C6—C7−7.0 (3)
C5—C4—S1—C1178.97 (18)C4—C5—C6—C7173.08 (15)
S1X—C4—S1—C1−4.5 (5)C5—C6—C7—C8179.63 (14)
C4—S1—C1—C21.5 (4)C6—C7—C8—C9173.21 (16)
S1—C1—C2—C3−2.2 (7)C6—C7—C8—C13−8.9 (3)
C3X—C4—C3—C2−2.2 (11)C16—O4—C9—C10−16.9 (2)
C5—C4—C3—C2179.9 (4)C16—O4—C9—C8164.24 (14)
S1X—C4—C3—C2155 (5)C13—C8—C9—O4−178.88 (13)
S1—C4—C3—C2−1.0 (7)C7—C8—C9—O4−0.9 (2)
C1—C2—C3—C42.1 (8)C13—C8—C9—C102.2 (2)
C3X—C4—S1X—C1X6(2)C7—C8—C9—C10−179.86 (14)
C3—C4—S1X—C1X−18 (4)O4—C9—C10—C11−179.94 (14)
C5—C4—S1X—C1X−175.8 (18)C8—C9—C10—C11−1.1 (2)
S1—C4—S1X—C1X7.8 (19)C15—O3—C11—C103.3 (2)
C4—S1X—C1X—C2X−11 (4)C15—O3—C11—C12−175.89 (14)
S1X—C1X—C2X—C3X12 (5)C9—C10—C11—O3179.05 (13)
C3—C4—C3X—C2X4(2)C9—C10—C11—C12−1.8 (2)
C5—C4—C3X—C2X−178.2 (17)C14—O2—C12—C13−2.3 (2)
S1X—C4—C3X—C2X0(3)C14—O2—C12—C11175.38 (14)
S1—C4—C3X—C2X−163 (13)O3—C11—C12—O24.99 (19)
C1X—C2X—C3X—C4−8(4)C10—C11—C12—O2−174.20 (13)
C3X—C4—C5—O16.3 (12)O3—C11—C12—C13−177.23 (13)
C3—C4—C5—O1−176.2 (4)C10—C11—C12—C133.6 (2)
S1X—C4—C5—O1−171.6 (5)O2—C12—C13—C8175.11 (14)
S1—C4—C5—O14.8 (2)C11—C12—C13—C8−2.4 (2)
C3X—C4—C5—C6−173.8 (12)C9—C8—C13—C12−0.4 (2)
C3—C4—C5—C63.7 (5)C7—C8—C13—C12−178.33 (14)
S1X—C4—C5—C68.3 (5)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C2—H2A···O1i0.932.553.363 (4)146
C7—H7A···O10.932.522.8416 (18)101
C7—H7A···O40.932.392.7477 (19)103
C16—H16B···O4ii0.962.563.2952 (19)133

Symmetry codes: (i) x, y+1, z; (ii) −x+1, −y−1, −z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: LH2658).

References

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