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Acta Crystallogr Sect E Struct Rep Online. 2010 September 1; 66(Pt 9): o2261–o2262.
Published online 2010 August 11. doi:  10.1107/S1600536810031193
PMCID: PMC3007858

(E)-1-[4-(Prop-2-yn-1-yl­oxy)phen­yl]-3-(3,4,5-trimeth­oxy­phen­yl)prop-2-en-1-one

Abstract

The mol­ecule of the title chalcone derivative, C21H20O5, consists of two substituted aromatic rings bridged by a prop-2-en-1-one group. The dihedral angle between the two benzene rings is 28.7 (7)°. In the crystal, mol­ecules are linked into C(10) chains running along the a axis by inter­molecular C—H(...)O hydrogen bonds, and the chains are cross-linked via C—H(...)π inter­actions.

Related literature

For the biological activity of chalcones, see: Di Carlo et al. (1999 [triangle]); Rao et al. (2004 [triangle]); Sabzevari et al. (2004 [triangle]); Litkei (1979 [triangle]); Pandey et al. (2005 [triangle]); Lawrence et al. (2001 [triangle]); Lin et al. (2002 [triangle]). For related structures, see: Suwunwong et al. (2009 [triangle]); Wu et al. (2005 [triangle]). For hydrogen-bond motifs, see: Bernstein et al. (1995 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o2261-scheme1.jpg

Experimental

Crystal data

  • C21H20O5
  • M r = 352.37
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o2261-efi1.jpg
  • a = 11.6344 (8) Å
  • b = 11.5970 (7) Å
  • c = 14.4169 (12) Å
  • β = 107.763 (5)°
  • V = 1852.5 (2) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 293 K
  • 0.25 × 0.22 × 0.19 mm

Data collection

  • Bruker APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.981, T max = 0.985
  • 17592 measured reflections
  • 4556 independent reflections
  • 3382 reflections with I > 2σ(I)
  • R int = 0.023

Refinement

  • R[F 2 > 2σ(F 2)] = 0.043
  • wR(F 2) = 0.128
  • S = 1.03
  • 4556 reflections
  • 242 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.23 e Å−3
  • Δρmin = −0.19 e Å−3

Data collection: APEX2 (Bruker, 2004 [triangle]); cell refinement: SAINT (Bruker, 2004 [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 (Farrugia, 1997 [triangle]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810031193/bt5297sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810031193/bt5297Isup2.hkl

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

Acknowledgments

SR and ASP thank the Technology Business Incubator (TBI), CAS in Crystallography and Biophysics, University of Madras, Chennai, and the Department of Science and Technology (DST) for the data collection.

supplementary crystallographic information

Comment

Chalcones are one of the major classes of natural products with widespread distribution in fruits, vegetables, spices, tea and soy based foodstuff have recently been subjects of great interest for their interesting pharmacological activities (Di Carlo et al., 1999). Chalcones are biosynthesized by plants, and an impressive number have been found toxic to cancer cells (Rao et al., 2004; Sabzevari et al., 2004). Chalcone epoxides have long been suspected as intermediates in the biosynthesis of plant flavonoids (Litkei, 1979). Chalcones can be easily obtained from the aldol condensation of aromatic aldehydes and aromatic ketones. This class of compounds presents interesting biological properties such as cytotoxicity (Pandey et al., 2005), antiherpes activity, antitumour activity and may be useful for the chemotherapy of leishmaniasis among others (Lawrence et al., 2001). Chalcones and flavonoids as anti-tuberculosis agents are also reported (Lin et al., 2002). Against this background, and in order to obtain detailed information on molecular conformations in the solid state, an X-ray study of the title compound was carried out.

X-Ray analysis confirms the molecular structure and atom connectivity as illustrated in Fig. 1. The bond distances are of normal values and are comparable with the closely related structures (Suwunwong et al., 2009; Wu et al., 2005). The molecule of the title chalcone derivative (Fig. 1) exists in an E configuration with respect to the C11—C12 double bond [1.323 (2) Å] with torsion angle C10—C11—C12—C13 = 172.4 (1)°. The whole molecule is not planar as the dihedral angle between the two phenyl rings is 28.7 (7)°. The propenone unit (C10—C12/O2) is nearly planar with the torsion angle O2—C10—C11—C12= -0.9 (2)°. Atoms O2, C7, C10, C11 and C12 lie on the same plane with the most deviation of -0.023 (1)Å for atom C10. The mean plane through O2/C7/C10/C11/C12 makes interplanar angles of 19.7 (8)° and 14.5 (7)° with the planes of the two phenyl rings, respectively. The atoms O1, O3, O4 and O5 deviate by 0.044 (1), 0.014 (1), 0.043 (1) and 0.012 (1) Å, respectively, from the plane of the attached phenyl rings.

In the solid state, the title molecule is characterized by an intramolecular C12–H12···O2 hydrogen bond in which the carbon atom acts as a donor to the adjacent keto O atom. This hydrogen bond is responsible for the coplanarity of the C4—C9 benzene ring with the central propenone chain. This hydrogen bond completes a five-membered ring, which generates an S(5) motif (Bernstein et al.,1995). The atom C19 acts as a donor to the atom O2 of the neighbour molecule at (-x + 1/2, y - 1/2, -z + 1/2). This hydrogen bond is involved in a motif C(10) forming a chain along a axis. In addition, the crystal packing is stabilized by a C–H···π interaction between one of the methyl H atoms (H20B) and the centroid (cg1) of the C13–C18 ring (Table 1).

Experimental

Compound was prepared through condensation of 4-hydroxyacetophenone (5 mmol, 1.57 g) with 3,4,5-trimethoxybenzaldehyde (5 mmol, 0.68 g) in 10% NaOH solution (1 ml), stirred at room temperature for 12 h (yield 65%, m.p. 146°C). The reaction mixture was poured into ice water (100 ml) and filtered. After the usual work-up, the product was purified by column chromatography. Further the corresponding phenol (2.0 g, 6.36 mmol) propargyl bromide (7.96 mmol) and anhydrous potassium carbonate (31.8 mmol) in dry DMF (15 ml) was stirred at 60°C for 24 h. The reaction mixture was then allowed to cool at room temperature and poured into ice water. The resulting precipitate was filtered, washed thoroughly with water and dissolved in CHCl3 (150 ml). The organic layer was seperated, washed with brine (1x150 ml), dried (anhydrous Na2SO4) and evaporated to give the crude dendron. Crystals suitable for X-ray diffraction were obtained by slow evaporation of a 95% chloroform solution.

Refinement

All H atoms were fixed geometrically and allowed to ride on their parent C atoms, with C—H distances fixed in the range 0.93–0.97 Å and with Uiso(H) = 1.5Ueq(C) for methyl H 1.2Ueq(C) for other H atoms.

Figures

Fig. 1.
The structure of showing the atom-numbering scheme and intramolecular hydrogen bond. Displacement ellipsoids are drawn at the 30% probability level.
Fig. 2.
The molecular packing viewed down the b axis. Dashed lines shows the intermolecular C–H···O hydrogen bonds.

Crystal data

C21H20O5F(000) = 744
Mr = 352.37Dx = 1.263 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 4556 reflections
a = 11.6344 (8) Åθ = 2.0–28.3°
b = 11.5970 (7) ŵ = 0.09 mm1
c = 14.4169 (12) ÅT = 293 K
β = 107.763 (5)°Block, white crystalline
V = 1852.5 (2) Å30.25 × 0.22 × 0.19 mm
Z = 4

Data collection

Bruker APEXII CCD area-detector diffractometer4556 independent reflections
Radiation source: fine-focus sealed tube3382 reflections with I > 2σ(I)
graphiteRint = 0.023
ω and [var phi] scansθmax = 28.3°, θmin = 2.0°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)h = −13→15
Tmin = 0.981, Tmax = 0.985k = −13→15
17592 measured reflectionsl = −19→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)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.128H atoms treated by a mixture of independent and constrained refinement
S = 1.03w = 1/[σ2(Fo2) + (0.061P)2 + 0.372P] where P = (Fo2 + 2Fc2)/3
4556 reflections(Δ/σ)max < 0.001
242 parametersΔρmax = 0.23 e Å3
0 restraintsΔρmin = −0.19 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
C10.66574 (17)0.75233 (16)0.97300 (13)0.0626 (4)
C20.62260 (15)0.70881 (13)0.89685 (11)0.0515 (4)
C30.56205 (15)0.65629 (13)0.80251 (11)0.0537 (4)
H3A0.47550.65540.79110.064*
H3B0.57860.70040.75090.064*
C40.55619 (14)0.47568 (12)0.72216 (9)0.0448 (3)
C50.46132 (14)0.51032 (13)0.64241 (10)0.0475 (3)
H50.42570.58220.64190.057*
C60.42044 (13)0.43671 (13)0.56392 (10)0.0466 (3)
H60.35660.45980.51070.056*
C70.47225 (12)0.32897 (12)0.56250 (10)0.0413 (3)
C80.56578 (14)0.29515 (13)0.64418 (11)0.0496 (4)
H80.60100.22300.64500.059*
C90.60697 (15)0.36650 (13)0.72363 (11)0.0525 (4)
H90.66840.34210.77810.063*
C100.42741 (13)0.25699 (12)0.47322 (10)0.0437 (3)
C110.50561 (13)0.16440 (12)0.45563 (10)0.0440 (3)
H110.57990.14980.50160.053*
C120.47078 (13)0.10202 (11)0.37496 (10)0.0433 (3)
H120.39200.11390.33550.052*
C130.54076 (12)0.01680 (11)0.34013 (9)0.0385 (3)
C140.49568 (12)−0.01780 (11)0.24300 (10)0.0411 (3)
H140.42060.00820.20470.049*
C150.56300 (12)−0.09099 (11)0.20353 (9)0.0384 (3)
C160.67466 (12)−0.13097 (11)0.26139 (9)0.0373 (3)
C170.71902 (12)−0.09784 (11)0.35925 (9)0.0378 (3)
C180.65216 (12)−0.02431 (11)0.39853 (9)0.0389 (3)
H180.6814−0.00240.46360.047*
C190.41300 (14)−0.09359 (15)0.04783 (11)0.0557 (4)
H19A0.3518−0.12130.07430.084*
H19B0.3999−0.1253−0.01610.084*
H19C0.4094−0.01100.04380.084*
C200.73073 (19)−0.32061 (14)0.24124 (15)0.0709 (5)
H20A0.7478−0.33160.31010.106*
H20B0.7867−0.36470.21860.106*
H20C0.6499−0.34570.20830.106*
C210.88002 (15)−0.10781 (15)0.50787 (11)0.0560 (4)
H21A0.8881−0.02540.51180.084*
H21B0.9580−0.14280.53420.084*
H21C0.8280−0.13270.54450.084*
O10.60592 (11)0.54149 (9)0.80317 (7)0.0595 (3)
O20.33027 (10)0.27793 (11)0.41288 (9)0.0656 (3)
O30.52865 (9)−0.12805 (9)0.10934 (7)0.0508 (3)
O40.74235 (9)−0.20129 (9)0.22148 (7)0.0471 (3)
O50.82941 (9)−0.14134 (9)0.40858 (7)0.0513 (3)
H10.6977 (17)0.7866 (17)1.0333 (15)0.081 (6)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0697 (11)0.0595 (10)0.0548 (10)0.0012 (8)0.0136 (8)−0.0162 (8)
C20.0608 (9)0.0438 (8)0.0507 (8)0.0022 (7)0.0183 (7)−0.0053 (6)
C30.0695 (10)0.0430 (8)0.0446 (8)0.0057 (7)0.0114 (7)−0.0059 (6)
C40.0563 (8)0.0421 (7)0.0354 (6)0.0020 (6)0.0133 (6)−0.0037 (5)
C50.0540 (8)0.0393 (7)0.0469 (7)0.0079 (6)0.0120 (6)−0.0060 (6)
C60.0440 (8)0.0470 (8)0.0461 (7)0.0050 (6)0.0098 (6)−0.0068 (6)
C70.0416 (7)0.0409 (7)0.0447 (7)−0.0006 (6)0.0182 (6)−0.0073 (6)
C80.0623 (9)0.0397 (7)0.0478 (8)0.0110 (7)0.0185 (7)−0.0008 (6)
C90.0627 (9)0.0499 (8)0.0403 (7)0.0129 (7)0.0085 (7)−0.0003 (6)
C100.0413 (7)0.0422 (7)0.0507 (8)−0.0013 (6)0.0185 (6)−0.0099 (6)
C110.0436 (7)0.0417 (7)0.0489 (7)0.0035 (6)0.0176 (6)−0.0060 (6)
C120.0442 (7)0.0384 (7)0.0506 (7)0.0023 (6)0.0195 (6)−0.0047 (6)
C130.0439 (7)0.0328 (6)0.0431 (7)−0.0010 (5)0.0198 (6)−0.0042 (5)
C140.0397 (7)0.0394 (7)0.0439 (7)0.0017 (6)0.0125 (6)−0.0047 (5)
C150.0436 (7)0.0360 (6)0.0361 (6)−0.0032 (5)0.0130 (5)−0.0056 (5)
C160.0440 (7)0.0315 (6)0.0398 (6)0.0017 (5)0.0179 (5)−0.0037 (5)
C170.0442 (7)0.0322 (6)0.0377 (6)0.0022 (5)0.0134 (5)0.0011 (5)
C180.0494 (8)0.0360 (6)0.0334 (6)0.0003 (5)0.0158 (5)−0.0031 (5)
C190.0524 (9)0.0623 (10)0.0454 (8)−0.0042 (7)0.0047 (7)−0.0069 (7)
C200.0933 (14)0.0419 (9)0.0845 (13)0.0139 (9)0.0375 (11)−0.0095 (8)
C210.0565 (9)0.0602 (9)0.0436 (8)0.0056 (8)0.0038 (7)−0.0048 (7)
O10.0829 (8)0.0467 (6)0.0391 (5)0.0131 (5)0.0040 (5)−0.0076 (4)
O20.0459 (6)0.0703 (8)0.0715 (8)0.0109 (5)0.0043 (5)−0.0307 (6)
O30.0498 (6)0.0608 (6)0.0380 (5)0.0056 (5)0.0077 (4)−0.0136 (4)
O40.0528 (6)0.0460 (6)0.0470 (5)0.0071 (4)0.0218 (4)−0.0092 (4)
O50.0522 (6)0.0549 (6)0.0414 (5)0.0158 (5)0.0063 (4)−0.0068 (4)

Geometric parameters (Å, °)

C1—C21.173 (2)C13—C141.3960 (18)
C1—H10.92 (2)C13—C181.3965 (19)
C2—C31.460 (2)C14—C151.3890 (18)
C3—O11.4248 (18)C14—H140.9300
C3—H3A0.9700C15—O31.3628 (15)
C3—H3B0.9700C15—C161.3918 (19)
C4—O11.3670 (16)C16—O41.3758 (15)
C4—C51.388 (2)C16—C171.4001 (17)
C4—C91.395 (2)C17—O51.3610 (16)
C5—C61.3810 (19)C17—C181.3862 (17)
C5—H50.9300C18—H180.9300
C6—C71.3901 (19)C19—O31.4242 (18)
C6—H60.9300C19—H19A0.9600
C7—C81.394 (2)C19—H19B0.9600
C7—C101.4886 (18)C19—H19C0.9600
C8—C91.375 (2)C20—O41.428 (2)
C8—H80.9300C20—H20A0.9600
C9—H90.9300C20—H20B0.9600
C10—O21.2220 (18)C20—H20C0.9600
C10—C111.4784 (18)C21—O51.4256 (17)
C11—C121.3239 (19)C21—H21A0.9600
C11—H110.9300C21—H21B0.9600
C12—C131.4632 (17)C21—H21C0.9600
C12—H120.9300
C2—C1—H1178.4 (12)C15—C14—C13120.02 (12)
C1—C2—C3176.70 (18)C15—C14—H14120.0
O1—C3—C2108.27 (12)C13—C14—H14120.0
O1—C3—H3A110.0O3—C15—C14124.77 (12)
C2—C3—H3A110.0O3—C15—C16115.37 (11)
O1—C3—H3B110.0C14—C15—C16119.86 (12)
C2—C3—H3B110.0O4—C16—C15119.71 (11)
H3A—C3—H3B108.4O4—C16—C17120.13 (12)
O1—C4—C5124.63 (13)C15—C16—C17120.15 (11)
O1—C4—C9115.27 (12)O5—C17—C18124.90 (11)
C5—C4—C9120.09 (13)O5—C17—C16115.08 (11)
C6—C5—C4119.20 (13)C18—C17—C16120.01 (12)
C6—C5—H5120.4C17—C18—C13119.80 (11)
C4—C5—H5120.4C17—C18—H18120.1
C5—C6—C7121.68 (13)C13—C18—H18120.1
C5—C6—H6119.2O3—C19—H19A109.5
C7—C6—H6119.2O3—C19—H19B109.5
C6—C7—C8118.08 (12)H19A—C19—H19B109.5
C6—C7—C10118.53 (13)O3—C19—H19C109.5
C8—C7—C10123.37 (12)H19A—C19—H19C109.5
C9—C8—C7121.21 (13)H19B—C19—H19C109.5
C9—C8—H8119.4O4—C20—H20A109.5
C7—C8—H8119.4O4—C20—H20B109.5
C8—C9—C4119.68 (14)H20A—C20—H20B109.5
C8—C9—H9120.2O4—C20—H20C109.5
C4—C9—H9120.2H20A—C20—H20C109.5
O2—C10—C11120.41 (12)H20B—C20—H20C109.5
O2—C10—C7120.54 (12)O5—C21—H21A109.5
C11—C10—C7118.94 (12)O5—C21—H21B109.5
C12—C11—C10120.54 (13)H21A—C21—H21B109.5
C12—C11—H11119.7O5—C21—H21C109.5
C10—C11—H11119.7H21A—C21—H21C109.5
C11—C12—C13128.12 (13)H21B—C21—H21C109.5
C11—C12—H12115.9C4—O1—C3117.30 (11)
C13—C12—H12115.9C15—O3—C19117.78 (11)
C14—C13—C18120.15 (12)C16—O4—C20112.95 (12)
C14—C13—C12117.40 (12)C17—O5—C21117.28 (11)
C18—C13—C12122.34 (12)
O1—C4—C5—C6178.74 (14)C13—C14—C15—C160.9 (2)
C9—C4—C5—C6−1.7 (2)O3—C15—C16—O41.05 (18)
C4—C5—C6—C7−0.3 (2)C14—C15—C16—O4−178.49 (12)
C5—C6—C7—C81.6 (2)O3—C15—C16—C17179.73 (12)
C5—C6—C7—C10−176.90 (14)C14—C15—C16—C170.2 (2)
C6—C7—C8—C9−0.8 (2)O4—C16—C17—O5−0.82 (18)
C10—C7—C8—C9177.62 (14)C15—C16—C17—O5−179.50 (12)
C7—C8—C9—C4−1.3 (2)O4—C16—C17—C18178.14 (12)
O1—C4—C9—C8−177.92 (14)C15—C16—C17—C18−0.53 (19)
C5—C4—C9—C82.5 (2)O5—C17—C18—C13178.66 (12)
C6—C7—C10—O2−17.5 (2)C16—C17—C18—C13−0.19 (19)
C8—C7—C10—O2164.17 (15)C14—C13—C18—C171.3 (2)
C6—C7—C10—C11158.74 (13)C12—C13—C18—C17−174.75 (12)
C8—C7—C10—C11−19.6 (2)C5—C4—O1—C3−4.2 (2)
O2—C10—C11—C12−0.9 (2)C9—C4—O1—C3176.24 (14)
C7—C10—C11—C12−177.07 (13)C2—C3—O1—C4177.33 (13)
C10—C11—C12—C13172.41 (13)C14—C15—O3—C19−3.0 (2)
C11—C12—C13—C14−165.06 (14)C16—C15—O3—C19177.52 (12)
C11—C12—C13—C1811.1 (2)C15—C16—O4—C20−98.73 (16)
C18—C13—C14—C15−1.6 (2)C17—C16—O4—C2082.59 (17)
C12—C13—C14—C15174.59 (12)C18—C17—O5—C21−0.5 (2)
C13—C14—C15—O3−178.61 (13)C16—C17—O5—C21178.43 (12)

Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C13–C18 ring.
D—H···AD—HH···AD···AD—H···A
C12—H12···O20.932.422.7710 (19)102
C19—H19A···O2i0.962.483.396 (2)161
C20—H20B···Cg1ii0.962.613.487 (2)152

Symmetry codes: (i) −x+1/2, y−1/2, −z+1/2; (ii) −x+3/2, y−1/2, −z+1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BT5297).

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