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Acta Crystallogr Sect E Struct Rep Online. 2008 August 1; 64(Pt 8): o1540–o1541.
Published online 2008 July 19. doi:  10.1107/S1600536808021776
PMCID: PMC2962165

1-(4-Bromo­phen­yl)-3-(4-ethoxy­phen­yl)­prop-2-en-1-one

Abstract

The title compound, C17H15BrO2, consists of two substituted benzene rings connected by a prop-2-en-1-one group. The mol­ecule is nearly planar and adopts an E configuration. The dihedral angle between the two benzene rings is 8.51 (19)°. The enone plane makes dihedral angles of 11.06 (19) and 7.69 (19)°, respectively, with the bromo­phenyl and ethoxy­phenyl rings. The mol­ecules are linked by C—H(...)O hydrogen bonds to form a zigzag ribbon-like structure along the b direction. The crystal structure is stabilized by weak intra- and inter­molecular C—H(...)O inter­actions.

Related literature

For hydrogen-bond motifs, see: Bernstein et al. (1995 [triangle]). For similar structures, see: Fun et al. (2008 [triangle]); Patil, Fun et al. (2007 [triangle]); Patil, Ng et al. (2007 [triangle]). For background on chalcones, see: Chopra et al. (2007 [triangle]); Fichou et al. (1988 [triangle]); Goto et al. (1991 [triangle]); Gu, Ji, Patil & Dharmaprakash (2008 [triangle]); Gu, Ji, Patil, Dharmaprakash & Wang (2008 [triangle]); Sathiya Moorthi, Chinnakali, Nanjundan, Radhika et al. (2005 [triangle]); Sathiya Moorthi, Chinnakali, Nanjundan, Selvam et al. (2005 [triangle]); Schmalle et al. (1990 [triangle]); Uchida et al. (1998 [triangle]); Wang et al. (2004 [triangle]); Zhao et al. (2000 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-64-o1540-scheme1.jpg

Experimental

Crystal data

  • C17H15BrO2
  • M r = 331.19
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-o1540-efi1.jpg
  • a = 3.9855 (1) Å
  • b = 10.0681 (3) Å
  • c = 17.5270 (4) Å
  • β = 92.227 (2)°
  • V = 702.77 (3) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 2.92 mm−1
  • T = 100.0 (1) K
  • 0.47 × 0.17 × 0.09 mm

Data collection

  • Bruker SMART APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2005 [triangle]) T min = 0.340, T max = 0.781
  • 7696 measured reflections
  • 2620 independent reflections
  • 2339 reflections with I > 2σ(I)
  • R int = 0.033

Refinement

  • R[F 2 > 2σ(F 2)] = 0.033
  • wR(F 2) = 0.095
  • S = 1.08
  • 2620 reflections
  • 182 parameters
  • 1 restraint
  • H-atom parameters constrained
  • Δρmax = 0.98 e Å−3
  • Δρmin = −0.53 e Å−3
  • Absolute structure: Flack (1983 [triangle]), 656 Friedel pairs
  • Flack parameter: 0.013 (13)

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/S1600536808021776/fl2206sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808021776/fl2206Isup2.hkl

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

Acknowledgments

This work is supported by the Department of Science and Technology (DST), Government of India, under grant No. SR/S2/LOP-17/2006. SC thanks the Prince of Songkla University for generous support. The authors also thank the Universiti Sains Malaysia for the Research University Golden Goose Grant No. 1001/PFIZIK/811012.

supplementary crystallographic information

Comment

Chalcone and its derivatives have received much attention due to their interesting biological (Nel et al., 1998) and non-linear optical properties (Chopra et al., 2007; Sathiya Moorthi, Chinnakali, Nanjundan, Radhika et al., 2005; Sathiya Moorthi, Chinnakali, Nanjundan, Selvam et al., 2005; Schmalle et al., 1990; Wang et al., 2004; Gu, Ji, Patil & Dharmaprakash, 2008; Gu, Ji, Patil, Dharmaprakash & Wang, 2008). Understanding the origin and magnitude of nonlinearity in such exotic molecules is very important from both a fundamental point of view and for its wide range of applications. Some chalcone derivatives exhibiting second harmonic generation (SHG) also possess other attributes such as transparency in the relevant wavelengths, ability to withstand laser irradiation, and chemical stability (Fichou et al., 1988; Goto et al., 1991; Uchida et al., 1998; Zhao et al., 2000). We previously reported the crystal structure of a related chalcone derivative, 1-(3-bromophenyl)-3-(4-ethoxyphenyl) prop-2-en-1-one, (II) (Fun et al., 2008). In our continuing systematic study, we report here the structure of the title compound, (I) which also crystallized in a non-centrosymmetric space group and, as with (II), it should exhibit second-order nonlinear optical properties.

The molecular structure of (I) (Fig. 1) consists of two planar six-membered rings C1–C6 (ring A) and C10–C15 (ring B), with maximum deviations of 0.009 (4) and -0.010 (4) Å for atoms C6 (ring A) and C12(ring B), respectively. The molecule exists in an E configuration with respect to the C8=C9 double bond [1.336 (6) Å]: the torsion angle C7–C8–C9–C10 = -179.4 (4)°. The molecule is nearly planar with a dihedral angle between rings A and B of 8.51 (19)° [10.09 (11)° in (II) by Fun et al., 2008]. The mean plane C through enone unit (C7–C9/O1) makes dihedral angles of 11.06 (19)° and 7.69 (19)° with the planes of rings A and B, respectively [the corresponding values are 12.05 (11)° and 9.87 (11)° in (II)]. The ethoxy group itself is slightly twisted as indicated by the torsion angle C13—O2—C16—C17 = 173.4 (4)° but co-planar with the attached benzene ring B with the torsion angle C16/O2/C13/C12 = -1.2 (6)°. A weak C9–H9A···O1 intramolecular interaction (Fig. 1) generates an S(5) ring motif (Bernstein et al., 1995). The overall conformation of (I) is flatter than that observed for (II) which can be attributed to the different positions of the Br substituent on ring A (para in (I) and meta in (II). The bond distances and angles in (I) have normal values and are comparable with a number of closely related structures (Fun et al., 2008; Patil, Fun et al., 2007; Patil, Ng et al., 2007).

In the crystal packing, the molecules are arranged in an anti-parallel manner and linked by weak C—H···O interactions (Table 1) into a zigzag ribbon-like structure along the b direction (Fig. 2 and Fig. 3). Similar packing characteristics were observed in (II) (Fun et al., 2008). In (I) the same weak C—H···O (C16—H16B···O1) interaction is involved in the ribbon-linkage but there is also an additional weak C—H···O interaction which links the molecules (Table 1). This is also due to the different positions of the meta and para Br substitutions in (I) and (II) which made (I) more favourable for the C—H···O contacts.

Experimental

The title compound was synthesized by the condensation of 4-ethoxybenzaldehyde (0.01 mol, 1.39 ml) with 4-bromoacetophenone (0.01 mol, 1.99 g) in methanol (60 ml) in the presence of a catalytic amount of sodium hydroxide solution (5 ml, 20%). After stirring for 3 h, the contents of the flask were poured into ice-cold water (500 ml) and left to stand for 4 h. The resulting crude solid was filtered and dried. Single crystals were obtained by recrystallization from acetone.

Refinement

All H atoms were placed in calculated positions, with C—H = 0.93 Å, Uiso = 1.2Ueq(C) for aromatic and CH, C—H = 0.97 Å, Uiso = 1.2Ueq(C) for CH2 and C—H = 0.96 Å, Uiso = 1.5Ueq(C) for CH3 atoms. A rotating group model was used for the methyl groups. The highest residual electron density peak is located at 0.78 Å from Br1 and the deepest hole is located at 0.84 Å from Br1.

Figures

Fig. 1.
The molecular structure of (I) showing 50% probability displacement ellipsoids and the atom-numbering scheme. The dashed line represents the intra-molcular C—H···O interaction.
Fig. 2.
Crystal packing for (I) viewed along the a axis showing an antiparallel arrangement of the molecules. Hydrogen bonds are shown as dashed lines.
Fig. 3.
Crystal packing for (I) showing the zigzag ribbon-like structure running along the b axis. Hydrogen bonds are shown as dashed lines.

Crystal data

C17H15BrO2F000 = 336
Mr = 331.19Dx = 1.565 Mg m3
Monoclinic, P21Mo Kα radiation λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 2620 reflections
a = 3.9855 (1) Åθ = 1.2–29.0º
b = 10.0681 (3) ŵ = 2.92 mm1
c = 17.5270 (4) ÅT = 100.0 (1) K
β = 92.227 (2)ºBlock, colorless
V = 702.77 (3) Å30.47 × 0.17 × 0.09 mm
Z = 2

Data collection

Bruker SMART APEXII CCD area-detector diffractometer2620 independent reflections
Radiation source: fine-focus sealed tube2339 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.033
Detector resolution: 8.33 pixels mm-1θmax = 29.0º
T = 100.0(1) Kθmin = 1.2º
ω scansh = −5→5
Absorption correction: multi-scan(SADABS; Bruker, 2005)k = −13→8
Tmin = 0.340, Tmax = 0.781l = −23→23
7696 measured reflections

Refinement

Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.033  w = 1/[σ2(Fo2) + (0.0562P)2] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.095(Δ/σ)max < 0.001
S = 1.08Δρmax = 0.98 e Å3
2620 reflectionsΔρmin = −0.53 e Å3
182 parametersExtinction correction: none
1 restraintAbsolute structure: Flack (1983), 640 Friedel pairs
Primary atom site location: structure-invariant direct methodsFlack parameter: 0.013 (13)
Secondary atom site location: difference Fourier map

Special details

Experimental. The low-temperature 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*/Ueq
Br10.43528 (8)0.23538 (6)0.502628 (18)0.02637 (12)
O1−0.1514 (7)0.6546 (3)0.77360 (17)0.0282 (7)
O20.5201 (7)0.5258 (3)1.22900 (16)0.0234 (6)
C10.0563 (11)0.5256 (4)0.6436 (3)0.0234 (9)
H1A−0.06040.60520.63790.028*
C20.1400 (10)0.4543 (4)0.5789 (2)0.0210 (8)
H2A0.08350.48590.53020.025*
C30.3114 (9)0.3340 (4)0.5890 (2)0.0195 (8)
C40.3966 (9)0.2855 (4)0.6611 (2)0.0229 (8)
H4A0.50970.20510.66690.027*
C50.3112 (10)0.3583 (4)0.7242 (2)0.0216 (8)
H5A0.36590.32580.77280.026*
C60.1443 (10)0.4796 (4)0.7165 (2)0.0197 (8)
C70.0421 (11)0.5603 (4)0.7834 (2)0.0241 (9)
C80.1824 (10)0.5255 (5)0.8602 (2)0.0249 (9)
H8A0.33560.45610.86550.030*
C90.0927 (10)0.5921 (4)0.9221 (2)0.0236 (9)
H9A−0.06260.66010.91420.028*
C100.2115 (10)0.5700 (4)1.0008 (2)0.0219 (8)
C110.4006 (10)0.4600 (4)1.0240 (3)0.0235 (9)
H11A0.45970.39790.98760.028*
C120.5036 (10)0.4399 (4)1.0993 (2)0.0241 (9)
H12A0.62520.36431.11330.029*
C130.4243 (10)0.5332 (4)1.1541 (2)0.0220 (8)
C140.2317 (10)0.6439 (4)1.1322 (2)0.0228 (9)
H14A0.17410.70591.16870.027*
C150.1258 (10)0.6625 (4)1.0569 (2)0.0223 (8)
H15A−0.00280.73651.04330.027*
C160.7128 (11)0.4120 (4)1.2541 (3)0.0247 (9)
H16A0.90750.40141.22310.030*
H16B0.57730.33221.24950.030*
C170.8217 (13)0.4350 (5)1.3364 (3)0.0328 (12)
H17A0.96050.36251.35410.049*
H17B0.62720.44071.36690.049*
H17C0.94650.51631.34060.049*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Br10.02618 (18)0.0284 (2)0.02459 (17)−0.0013 (3)0.00238 (12)−0.0061 (2)
O10.0305 (16)0.0211 (17)0.0332 (16)0.0038 (13)0.0033 (13)−0.0008 (13)
O20.0222 (14)0.0203 (15)0.0275 (14)0.0029 (12)−0.0015 (12)−0.0018 (12)
C10.026 (2)0.014 (2)0.030 (2)−0.0016 (19)0.0027 (18)0.0004 (18)
C20.0227 (19)0.019 (2)0.0218 (18)−0.0029 (17)0.0000 (15)0.0045 (15)
C30.0184 (17)0.017 (2)0.0229 (18)−0.0049 (15)0.0036 (14)−0.0029 (15)
C40.0199 (17)0.0192 (18)0.029 (2)0.0005 (17)−0.0002 (15)0.0007 (17)
C50.0247 (19)0.017 (2)0.0226 (19)−0.0001 (16)−0.0030 (16)0.0040 (16)
C60.021 (2)0.0155 (18)0.0222 (18)−0.0033 (15)0.0012 (16)−0.0020 (17)
C70.026 (2)0.020 (2)0.027 (2)−0.0048 (17)0.0057 (17)0.0006 (17)
C80.0225 (19)0.020 (2)0.032 (2)0.0018 (17)0.0013 (17)0.0015 (18)
C90.0233 (19)0.018 (2)0.029 (2)−0.0030 (17)0.0013 (16)−0.0010 (17)
C100.0191 (18)0.018 (2)0.029 (2)−0.0054 (16)0.0046 (15)−0.0038 (16)
C110.023 (2)0.016 (2)0.032 (2)−0.0033 (16)0.0084 (16)−0.0057 (16)
C120.0209 (19)0.0152 (19)0.036 (2)0.0016 (17)0.0035 (17)−0.0028 (18)
C130.0178 (18)0.0172 (19)0.031 (2)−0.0035 (16)0.0026 (16)−0.0046 (17)
C140.0220 (19)0.0169 (19)0.030 (2)−0.0018 (16)0.0029 (16)−0.0068 (17)
C150.0201 (18)0.017 (2)0.030 (2)−0.0004 (15)0.0011 (16)−0.0030 (16)
C160.024 (2)0.013 (2)0.037 (2)−0.0003 (16)−0.0013 (18)0.0026 (18)
C170.032 (3)0.025 (2)0.042 (3)−0.002 (2)−0.003 (2)0.008 (2)

Geometric parameters (Å, °)

Br1—C31.892 (4)C9—C101.456 (6)
O1—C71.231 (5)C9—H9A0.9300
O2—C131.354 (5)C10—C111.392 (6)
O2—C161.438 (5)C10—C151.406 (6)
C1—C61.391 (6)C11—C121.383 (6)
C1—C21.393 (6)C11—H11A0.9300
C1—H1A0.9300C12—C131.389 (6)
C2—C31.399 (6)C12—H12A0.9300
C2—H2A0.9300C13—C141.399 (6)
C3—C41.385 (6)C14—C151.383 (6)
C4—C51.381 (6)C14—H14A0.9300
C4—H4A0.9300C15—H15A0.9300
C5—C61.395 (6)C16—C171.508 (6)
C5—H5A0.9300C16—H16A0.9700
C6—C71.496 (6)C16—H16B0.9700
C7—C81.480 (6)C17—H17A0.9600
C8—C91.336 (6)C17—H17B0.9600
C8—H8A0.9300C17—H17C0.9600
C13—O2—C16117.9 (3)C11—C10—C9123.4 (4)
C6—C1—C2121.1 (4)C15—C10—C9118.8 (4)
C6—C1—H1A119.5C12—C11—C10122.2 (4)
C2—C1—H1A119.5C12—C11—H11A118.9
C1—C2—C3118.3 (4)C10—C11—H11A118.9
C1—C2—H2A120.8C11—C12—C13119.6 (4)
C3—C2—H2A120.8C11—C12—H12A120.2
C4—C3—C2121.5 (4)C13—C12—H12A120.2
C4—C3—Br1118.9 (3)O2—C13—C12124.7 (4)
C2—C3—Br1119.6 (3)O2—C13—C14116.2 (4)
C5—C4—C3119.0 (4)C12—C13—C14119.1 (4)
C5—C4—H4A120.5C15—C14—C13121.0 (4)
C3—C4—H4A120.5C15—C14—H14A119.5
C4—C5—C6121.2 (4)C13—C14—H14A119.5
C4—C5—H5A119.4C14—C15—C10120.3 (4)
C6—C5—H5A119.4C14—C15—H15A119.8
C1—C6—C5118.9 (4)C10—C15—H15A119.8
C1—C6—C7118.2 (4)O2—C16—C17107.5 (4)
C5—C6—C7122.8 (4)O2—C16—H16A110.2
O1—C7—C8121.5 (4)C17—C16—H16A110.2
O1—C7—C6119.8 (4)O2—C16—H16B110.2
C8—C7—C6118.7 (4)C17—C16—H16B110.2
C9—C8—C7121.1 (4)H16A—C16—H16B108.5
C9—C8—H8A119.4C16—C17—H17A109.5
C7—C8—H8A119.4C16—C17—H17B109.5
C8—C9—C10127.2 (4)H17A—C17—H17B109.5
C8—C9—H9A116.4C16—C17—H17C109.5
C10—C9—H9A116.4H17A—C17—H17C109.5
C11—C10—C15117.8 (4)H17B—C17—H17C109.5
C6—C1—C2—C30.9 (6)C7—C8—C9—C10−179.4 (4)
C1—C2—C3—C40.2 (6)C8—C9—C10—C11−10.6 (7)
C1—C2—C3—Br1−179.1 (3)C8—C9—C10—C15170.8 (4)
C2—C3—C4—C5−0.3 (6)C15—C10—C11—C120.1 (6)
Br1—C3—C4—C5179.0 (3)C9—C10—C11—C12−178.5 (4)
C3—C4—C5—C6−0.6 (6)C10—C11—C12—C13−1.5 (6)
C2—C1—C6—C5−1.8 (6)C16—O2—C13—C12−1.2 (6)
C2—C1—C6—C7−179.2 (4)C16—O2—C13—C14178.8 (3)
C4—C5—C6—C11.6 (6)C11—C12—C13—O2−178.0 (4)
C4—C5—C6—C7178.9 (4)C11—C12—C13—C142.1 (6)
C1—C6—C7—O19.3 (6)O2—C13—C14—C15178.8 (4)
C5—C6—C7—O1−168.0 (4)C12—C13—C14—C15−1.2 (6)
C1—C6—C7—C8−169.7 (4)C13—C14—C15—C10−0.2 (6)
C5—C6—C7—C813.0 (6)C11—C10—C15—C140.8 (6)
O1—C7—C8—C92.8 (7)C9—C10—C15—C14179.4 (4)
C6—C7—C8—C9−178.3 (4)C13—O2—C16—C17173.4 (4)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C4—H4A···O2i0.932.573.257 (5)131
C9—H9A···O10.932.482.814 (5)102
C16—H16B···O1ii0.972.493.446 (5)170

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: FL2206).

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