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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 69| Part 5| May 2013| Page o812
https://doi.org/10.1107/S1600536813011288

(E)-3-[4-(Di­fluoro­meth­­oxy)-3-hy­dr­oxy­phen­yl]-1-phenyl­prop-2-en-1-one

Thothadri Srinivasan,a Govindaraj Senthilkumar,b Kaliaperumal Neelakandan,b Haridoss Manikandanb and Devadasan Velmurugana*

aCentre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India, and bDepartment of Chemistry, Annamalai University, Annamalainagar 608 002, Tamilnadu, India
*Correspondence e-mail: shirai2011@gmail.com

(Received 5 April 2013; accepted 25 April 2013; online 30 April 2013)

In the title compound, C16H12F2O3, the plane of the phenyl ring makes a dihedral angle of 3.22 (8)° with that of the benzene ring. The mol­ecule has an E conformation about the C=C bond. In the crystal, mol­ecules are linked via pairs of O—H⋯O hydrogen bonds, forming inversion dimers which are further consolidated by a pair of C—H⋯O hydrogen bonds. The dimers are linked via C—H⋯O hydrogen bonds, forming columns along the b-axis direction.

Related literature

For the biological activity of chalcones, see: Di Carlo et al. (1999[Di Carlo, G., Mascolo, N., Izzo, A. A. & Capasso, F. (1999). Life Sci. 65, 337-353.]); Lin et al. (2002[Lin, Y. M., Zhou, Y., Flavin, M. T., Zhou, L. M., Nie, W. & Chen, F. C. (2002). Bioorg. Med. Chem. 10, 2795-2802.]). For a related structure, see: Ranjith et al. (2010[Ranjith, S., Thirunarayanan, A., Raja, S., Rajakumar, P. & SubbiahPandi, A. (2010). Acta Cryst. E66, o2261-o2262.]).

[Scheme 1]

Experimental

Crystal data

  • C16H12F2O3

  • Mr = 290.26

  • Monoclinic, P 21 /n

  • a = 17.1880 (11) Å

  • b = 4.1124 (3) Å

  • c = 19.6699 (13) Å

  • β = 106.289 (4)°

  • V = 1334.54 (16) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.12 mm−1

  • T = 293 K

  • 0.30 × 0.25 × 0.20 mm
Data collection

  • Bruker SMART APEXII area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.966, Tmax = 0.977

  • 12412 measured reflections

  • 3328 independent reflections

  • 2456 reflections with I > 2σ(I)

  • Rint = 0.028
Refinement

  • R[F2 > 2σ(F2)] = 0.041

  • wR(F2) = 0.120

  • S = 1.03

  • 3328 reflections

  • 191 parameters

  • H-atom parameters constrained

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.18 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O2—H2⋯O3i 0.82 1.96 2.7722 (16) 172
C4—H4⋯O3i 0.93 2.48 3.1940 (19) 134
C1—H1⋯O1ii 0.98 2.40 3.3022 (19) 152
Symmetry codes: (i) -x+1, -y+1, -z; (ii) x, y-1, z.

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536813011288/su2584sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536813011288/su2584Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536813011288/su2584Isup3.cml

checkCIF report


Comment top

Chalcones are a major classes of natural products with widespread distribution in fruits, vegetables, spices, tea and soy based foodstuff and have recently been the subject of great interest for their interesting pharmacological activities (Di Carlo et al., 1999). Chalcones and flavonoids have been reported to be anti-tuberculosis agents (Lin et al., 2002). Against this background and in order to obtain detailed information on molecular conformations in the solid state of similar compounds, we report herein on the synthesis and crystal structure of the title compound.

In the title compound, Fig. 1, the phenyl ring (C2-C7) makes a dihedral angle of 3.22 (8)° with the benzene ring (C11-C16). The hydroxyl oxygen atom, O2, deviates by -0.0243 (12) Å from the benzene ring mean plane.

In the crystal, molecules are linked via a pair of O-H···O hydrogen bonds forming inversion dimers which are further consolidated by a pair of C-H···O hydrogen bonds (Fig. 2 and Table 1). The dimers are linked via C-H···O hydrogen bonds forming columns along the b axis direction (Table 1).

Related literature top

For the biological activity of chalcones, see: Di Carlo et al. (1999); Lin et al. (2002). For a related structure, see: Ranjith et al. (2010).

Experimental top

A mixture of 3-hydroxy-4-difluoromethoxybezaldehyde (2 mmol), acetophenone (2 mmol) and sodiumhydroxide (2 mmol) in ethanol were placed in a conical flask and exposed to ultrasound irradiation. The reaction mixture was monitored by TLC. After completion of the reaction, the mixture was acidified with dilute HCl and kept in the fridge overnight. The product that separated out was washed with distilled water and recrystallized from ethanol [Yield = 96%; M.p. = 409-411 K]. Colourless block-like crystals, suitable for X-ray diffraction analysis, were obtained by slow evaporation of a solution of the title compound in hexane at room temperature.

Refinement top

H atoms were placed in calculated positions, with O-H = 0.82 Å and C—H = 0.93-0.98 Å, and refined in a riding model with Uiso(H) = 1.5Ueq(O) and = 1.2Ueq(C).

Structure description top

Chalcones are a major classes of natural products with widespread distribution in fruits, vegetables, spices, tea and soy based foodstuff and have recently been the subject of great interest for their interesting pharmacological activities (Di Carlo et al., 1999). Chalcones and flavonoids have been reported to be anti-tuberculosis agents (Lin et al., 2002). Against this background and in order to obtain detailed information on molecular conformations in the solid state of similar compounds, we report herein on the synthesis and crystal structure of the title compound.

In the title compound, Fig. 1, the phenyl ring (C2-C7) makes a dihedral angle of 3.22 (8)° with the benzene ring (C11-C16). The hydroxyl oxygen atom, O2, deviates by -0.0243 (12) Å from the benzene ring mean plane.

In the crystal, molecules are linked via a pair of O-H···O hydrogen bonds forming inversion dimers which are further consolidated by a pair of C-H···O hydrogen bonds (Fig. 2 and Table 1). The dimers are linked via C-H···O hydrogen bonds forming columns along the b axis direction (Table 1).

For the biological activity of chalcones, see: Di Carlo et al. (1999); Lin et al. (2002). For a related structure, see: Ranjith et al. (2010).

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule, with atom labelling. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. The crystal packing of the title compound viewed along the b axis. Hydrogen bonds are shown as dashed lines (see Table 1 for details; H-atoms not involved in hydrogen bonding have been omitted for clarity).
(E)-3-[4-(Difluoromethoxy)-3-hydroxyphenyl]-1-phenylprop-2-en-1-one top
Crystal data top
C16H12F2O3F(000) = 600
Mr = 290.26Dx = 1.445 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 3328 reflections
a = 17.1880 (11) Åθ = 1.4–28.3°
b = 4.1124 (3) ŵ = 0.12 mm−1
c = 19.6699 (13) ÅT = 293 K
β = 106.289 (4)°Block, colourless
V = 1334.54 (16) Å30.30 × 0.25 × 0.20 mm
Z = 4
Data collection top
Bruker SMART APEXII area-detector
diffractometer		3328 independent reflections
Radiation source: fine-focus sealed tube2456 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.028
ω and φ scansθmax = 28.3°, θmin = 1.4°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)		h = −22→21
Tmin = 0.966, Tmax = 0.977k = −5→5
12412 measured reflectionsl = −26→23
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.041Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.120H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0528P)2 + 0.3218P]
where P = (Fo2 + 2Fc2)/3
3328 reflections(Δ/σ)max < 0.001
191 parametersΔρmax = 0.21 e Å−3
0 restraintsΔρmin = −0.18 e Å−3
Crystal data top
C16H12F2O3V = 1334.54 (16) Å3
Mr = 290.26Z = 4
Monoclinic, P21/nMo Kα radiation
a = 17.1880 (11) ŵ = 0.12 mm−1
b = 4.1124 (3) ÅT = 293 K
c = 19.6699 (13) Å0.30 × 0.25 × 0.20 mm
β = 106.289 (4)°
Data collection top
Bruker SMART APEXII area-detector
diffractometer		3328 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)		2456 reflections with I > 2σ(I)
Tmin = 0.966, Tmax = 0.977Rint = 0.028
12412 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0410 restraints
wR(F2) = 0.120H-atom parameters constrained
S = 1.03Δρmax = 0.21 e Å−3
3328 reflectionsΔρmin = −0.18 e Å−3
191 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. #========================================================================= # 8. Refinement Data #========================================================================= 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 > 2sigma(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) top
xyzUiso*/Ueq
C10.58013 (9)0.9403 (4)0.34909 (8)0.0501 (4)
H10.55530.73230.33050.060*
C20.57744 (8)1.0801 (3)0.23416 (7)0.0408 (3)
C30.52043 (8)0.8962 (3)0.18585 (7)0.0406 (3)
C40.53484 (8)0.8222 (4)0.12164 (7)0.0421 (3)
H40.49690.70010.08850.051*
C50.60481 (7)0.9264 (3)0.10571 (7)0.0399 (3)
C60.66097 (8)1.1133 (4)0.15554 (7)0.0459 (3)
H60.70781.18720.14570.055*
C70.64685 (9)1.1882 (4)0.21944 (8)0.0478 (3)
H70.68431.31200.25270.057*
C80.61704 (8)0.8271 (4)0.03816 (7)0.0443 (3)
H80.57630.69900.00940.053*
C90.67854 (8)0.8960 (4)0.01260 (7)0.0471 (3)
H90.72031.02750.03880.057*
C100.68243 (8)0.7696 (4)−0.05624 (7)0.0434 (3)
C110.75269 (8)0.8529 (3)−0.08315 (7)0.0429 (3)
C120.75121 (10)0.7547 (4)−0.15079 (8)0.0587 (4)
H120.70620.6441−0.17850.070*
C130.81561 (11)0.8191 (5)−0.17761 (9)0.0662 (5)
H130.81430.7488−0.22290.079*
C140.88160 (10)0.9868 (5)−0.13757 (10)0.0655 (5)
H140.92471.0326−0.15600.079*
C150.88416 (10)1.0869 (5)−0.07064 (10)0.0710 (5)
H150.92911.1997−0.04350.085*
C160.81987 (9)1.0202 (4)−0.04329 (8)0.0576 (4)
H160.82191.08850.00220.069*
O10.56344 (6)1.1715 (2)0.29861 (5)0.0490 (3)
O20.45380 (6)0.7923 (3)0.20384 (5)0.0547 (3)
H20.42530.68300.17150.082*
O30.62832 (6)0.5935 (3)−0.09091 (6)0.0615 (3)
F10.65995 (7)0.9098 (4)0.37665 (6)0.1057 (5)
F20.55249 (7)1.0449 (3)0.40166 (5)0.0779 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0568 (8)0.0515 (8)0.0449 (7)0.0069 (7)0.0190 (6)−0.0019 (6)
C20.0461 (7)0.0362 (7)0.0401 (6)0.0061 (6)0.0120 (5)−0.0010 (5)
C30.0368 (6)0.0450 (7)0.0406 (6)0.0024 (6)0.0120 (5)0.0022 (6)
C40.0366 (6)0.0507 (8)0.0384 (6)−0.0055 (6)0.0097 (5)−0.0029 (6)
C50.0374 (6)0.0424 (7)0.0404 (6)0.0006 (5)0.0116 (5)0.0038 (5)
C60.0398 (7)0.0487 (8)0.0508 (8)−0.0063 (6)0.0153 (6)0.0009 (6)
C70.0480 (7)0.0440 (8)0.0486 (7)−0.0067 (6)0.0090 (6)−0.0057 (6)
C80.0409 (7)0.0521 (8)0.0406 (7)−0.0057 (6)0.0124 (5)0.0000 (6)
C90.0429 (7)0.0560 (9)0.0441 (7)−0.0083 (6)0.0150 (6)−0.0016 (6)
C100.0395 (7)0.0498 (8)0.0419 (7)−0.0032 (6)0.0128 (5)0.0042 (6)
C110.0420 (7)0.0457 (8)0.0436 (7)0.0005 (6)0.0165 (5)0.0058 (6)
C120.0577 (9)0.0730 (11)0.0498 (8)−0.0128 (8)0.0224 (7)−0.0035 (8)
C130.0730 (11)0.0793 (12)0.0581 (9)−0.0036 (10)0.0377 (8)0.0019 (9)
C140.0554 (9)0.0719 (11)0.0814 (12)0.0000 (8)0.0394 (9)0.0111 (10)
C150.0479 (9)0.0908 (14)0.0791 (12)−0.0185 (9)0.0258 (8)−0.0072 (10)
C160.0483 (8)0.0727 (11)0.0551 (8)−0.0111 (8)0.0200 (7)−0.0068 (8)
O10.0638 (6)0.0415 (5)0.0433 (5)0.0093 (5)0.0178 (4)−0.0050 (4)
O20.0452 (5)0.0768 (8)0.0471 (5)−0.0116 (5)0.0214 (4)−0.0088 (5)
O30.0530 (6)0.0835 (8)0.0511 (6)−0.0251 (6)0.0199 (5)−0.0131 (6)
F10.0658 (7)0.1779 (15)0.0725 (7)0.0482 (8)0.0180 (5)0.0333 (8)
F20.0913 (8)0.0979 (8)0.0562 (6)0.0185 (6)0.0402 (5)−0.0023 (5)
Geometric parameters (Å, º) top
C1—F21.3250 (16)C8—H80.9300
C1—F11.3322 (18)C9—C101.4693 (19)
C1—O11.3461 (18)C9—H90.9300
C1—H10.9800C10—O31.2244 (16)
C2—C71.378 (2)C10—C111.4880 (17)
C2—C31.3830 (19)C11—C161.383 (2)
C2—O11.4063 (16)C11—C121.384 (2)
C3—O21.3589 (15)C12—C131.379 (2)
C3—C41.3873 (18)C12—H120.9300
C4—C51.3925 (17)C13—C141.372 (3)
C4—H40.9300C13—H130.9300
C5—C61.3974 (19)C14—C151.368 (3)
C5—C81.4605 (18)C14—H140.9300
C6—C71.380 (2)C15—C161.385 (2)
C6—H60.9300C15—H150.9300
C7—H70.9300C16—H160.9300
C8—C91.3223 (18)O2—H20.8200
F2—C1—F1105.47 (13)C8—C9—C10121.50 (13)
F2—C1—O1107.31 (12)C8—C9—H9119.3
F1—C1—O1110.42 (14)C10—C9—H9119.3
F2—C1—H1111.1O3—C10—C9119.92 (12)
F1—C1—H1111.1O3—C10—C11120.23 (12)
O1—C1—H1111.1C9—C10—C11119.85 (12)
C7—C2—C3121.35 (12)C16—C11—C12118.51 (13)
C7—C2—O1118.71 (12)C16—C11—C10122.99 (13)
C3—C2—O1119.88 (12)C12—C11—C10118.50 (13)
O2—C3—C2118.64 (12)C13—C12—C11120.78 (15)
O2—C3—C4123.15 (12)C13—C12—H12119.6
C2—C3—C4118.20 (12)C11—C12—H12119.6
C3—C4—C5121.55 (12)C14—C13—C12120.00 (16)
C3—C4—H4119.2C14—C13—H13120.0
C5—C4—H4119.2C12—C13—H13120.0
C4—C5—C6118.80 (12)C15—C14—C13120.14 (15)
C4—C5—C8118.20 (12)C15—C14—H14119.9
C6—C5—C8122.99 (12)C13—C14—H14119.9
C7—C6—C5119.88 (12)C14—C15—C16120.01 (16)
C7—C6—H6120.1C14—C15—H15120.0
C5—C6—H6120.1C16—C15—H15120.0
C2—C7—C6120.21 (13)C11—C16—C15120.55 (15)
C2—C7—H7119.9C11—C16—H16119.7
C6—C7—H7119.9C15—C16—H16119.7
C9—C8—C5128.35 (13)C1—O1—C2114.90 (10)
C9—C8—H8115.8C3—O2—H2109.5
C5—C8—H8115.8
C7—C2—C3—O2178.98 (13)C8—C9—C10—C11179.99 (14)
O1—C2—C3—O2−3.68 (19)O3—C10—C11—C16−172.66 (15)
C7—C2—C3—C40.0 (2)C9—C10—C11—C166.6 (2)
O1—C2—C3—C4177.37 (12)O3—C10—C11—C126.5 (2)
O2—C3—C4—C5−178.42 (13)C9—C10—C11—C12−174.29 (14)
C2—C3—C4—C50.5 (2)C16—C11—C12—C130.7 (3)
C3—C4—C5—C6−0.8 (2)C10—C11—C12—C13−178.48 (15)
C3—C4—C5—C8177.55 (13)C11—C12—C13—C14−1.1 (3)
C4—C5—C6—C70.7 (2)C12—C13—C14—C150.9 (3)
C8—C5—C6—C7−177.60 (14)C13—C14—C15—C16−0.3 (3)
C3—C2—C7—C6−0.2 (2)C12—C11—C16—C15−0.1 (3)
O1—C2—C7—C6−177.53 (12)C10—C11—C16—C15179.00 (16)
C5—C6—C7—C2−0.2 (2)C14—C15—C16—C11−0.1 (3)
C4—C5—C8—C9−179.68 (15)F2—C1—O1—C2−170.69 (12)
C6—C5—C8—C9−1.4 (3)F1—C1—O1—C274.84 (16)
C5—C8—C9—C10178.56 (14)C7—C2—O1—C1−101.79 (16)
C8—C9—C10—O3−0.8 (2)C3—C2—O1—C180.80 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O3i0.821.962.7722 (16)172
C4—H4···O3i0.932.483.1940 (19)134
C1—H1···O1ii0.982.403.3022 (19)152
Symmetry codes: (i) −x+1, −y+1, −z; (ii) x, y−1, z.

Experimental details

Crystal data
Chemical formulaC16H12F2O3
Mr290.26
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)17.1880 (11), 4.1124 (3), 19.6699 (13)
β (°) 106.289 (4)
V (Å3)1334.54 (16)
Z4
Radiation typeMo Kα
µ (mm−1)0.12
Crystal size (mm)0.30 × 0.25 × 0.20
Data collection
DiffractometerBruker SMART APEXII area-detector
Absorption correctionMulti-scan
(SADABS; Bruker, 2008)
Tmin, Tmax0.966, 0.977
No. of measured, independent and
observed [I > 2σ(I)] reflections		12412, 3328, 2456
Rint0.028
(sin θ/λ)max (Å−1)0.668
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.041, 0.120, 1.03
No. of reflections3328
No. of parameters191
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.21, −0.18

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O3i0.821.962.7722 (16)172
C4—H4···O3i0.932.483.1940 (19)134
C1—H1···O1ii0.982.403.3022 (19)152
Symmetry codes: (i) −x+1, −y+1, −z; (ii) x, y−1, z.
 

Acknowledgements

The authors thank the TBI X-ray facility, CAS in Crystallography and Biophysics, University of Madras, India, for the data collection. TS and DV thank the UGC (SAP–CAS) for the departmental facilties. TS also thanks the DST Inspire program for financial assistance.

References

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ISSN: 2056-9890
Volume 69| Part 5| May 2013| Page o812
https://doi.org/10.1107/S1600536813011288
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