(E)-1-(4-Fluoro-2-hy­droxy­phen­yl)-3-(2,3,4-tri­meth­oxy­phen­yl)prop-2-en-1-one

Yoo, M.; Koh, D.

doi:10.1107/S2414314620000711

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 5| Part 1| January 2020| x200071

https://doi.org/10.1107/S2414314620000711

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(E)-1-(4-Fluoro-2-hydroxyphenyl)-3-(2,3,4-trimethoxyphenyl)prop-2-en-1-one

Miri Yoo ^a and Dongsoo Koh ^a ^*

^aDepartment of Applied Chemistry, Dongduk Women's University, Seoul 136-714, Republic of Korea
^*Correspondence e-mail: dskoh@dongduk.ac.kr

Edited by A. J. Lough, University of Toronto, Canada (Received 14 January 2020; accepted 21 January 2020; online 24 January 2020)

In the title molecule, C₁₈H₁₇FO₅, the conformation about the C=C bond of the central enone group is trans. The dihedral angle between the benzene rings is 13.08 (3)°. The hydroxy group attached to the benzene ring is involved in an intramolecular O—H⋯O hydrogen bond. In the crystal, weak C—H⋯O hydrogen bonds link the molecules into chains along [001].

Keywords: crystal structure; chalcone; C—H⋯O hydrogen bonds; dihedral angle.

CCDC reference: 1979111

Structure description

Chalcones are α,β-unsaturated carbonyl (enone) compounds, which connect two aromatic rings. Especially when they have a hydroxyl group at the ortho position of an aromatic ring adjacent to the carbonyl group, they play important roles as precursors to form other flavonoids such as flavones, flavanones, flavonols and isoflavones (Marais et al., 2005 ). A variety of chlacones have been isolated from natural sources and synthesized because they have shown wide spectrum of biological activities against various diseases according to a recent review (Zhuang et al., 2017 ). In a continuation of our research interests to prepare new chalcones that show broad range of biological activities (Gil et al., 2018 , Park et al., 2018 ), the crystal structure of title compound has been determined.

The molecular structure of the title compound is shown in Fig. 1. In the central enone group, the trans configuration of the C2=C3 double bond is confirmed by the C1—C2=C3—C4 torsion angle of −176.6 (2)°. An intramolecular O5—H5⋯O1 hydrogen bond (Table 1) appears to cause the C1=O1 double bond [1.239 (2) Å] to be slightly longer than the normal value (Allen et al., 1987 ). The dihedral angle between the two benzene rings is 13.08 (3)°. Among the methoxy groups attached to the C4 benzene ring, the methoxy group at the meta position is almost perpendicular to the benzene ring [C5—C6—O3—C11 = 86.3 (2)°] and the para methoxy group is almost coplanar with the ring [C6—C7—O4—C12 = 177.1 (2)°]. The methoxy group at the ortho position is rotated significantly from the ring plane [C4—C5—O2—C10 = −123.9 (2)°]. In the crystal, weak C—H⋯O hydrogen bonds link the molecules into chains propagating along [001] (Table 1, Fig. 2).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O5—H5⋯O1	0.83	1.77	2.499 (2)	146
C18—H18⋯O5ⁱ	0.94	2.52	3.279 (2)	138
Symmetry code: (i) $[x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Figure 1
The molecular structure of the title compound, showing the atom-labelling scheme with displacement ellipsoids drawn at the 30% probability level. The intramolecular hydrogen bond is shown as a dashed line.

Figure 2
Part of the crystal structure with the intramolecular O—H⋯O hydrogen bond and weak C—H⋯O hydrogen bonds shown as dashed lines. For the sake of clarity, only the H atoms involved in hydrogen bonds are shown [symmetry codes: (i) x, −y + $[{1\over 2}]$ , z − $[{1\over 2}]$ ; (ii) x, −y + $[{1\over 2}]$ , z + $[{1\over 2}]$ ].

Synthesis and crystallization

To a solution of 1-(4-fluoro-2-hydroxyphenyl)ethanone (309 mg, 2 mmol) in 40 ml of anhydrous ethanol was added 2,3,4-trimethoxybenzaldehyde (392 mg, 2 mmol) and the temperature was adjusted to around 275–277 K in an ice bath. To the cooled reaction mixture was added 3 ml of 40% aqueous KOH solution and the reaction mixture was stirred at room temperature for 20 h. After completion of the reaction (monitored by thin-layer chromatography), this mixture was poured into ice water (100 ml) and the resulting solution acidified with 6 N HCl solution until pH = 3 to produce a solid product. This solid was recrystallized from an ethanol solution to obtain single crystals of the title compound in 54% yield.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	C₁₈H₁₇FO₅
M_r	332.32
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	223
a, b, c (Å)	15.5801 (12), 8.3414 (6), 12.1298 (8)
β (°)	97.086 (3)
V (Å³)	1564.35 (19)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.11
Crystal size (mm)	0.21 × 0.15 × 0.10

Data collection
Diffractometer	PHOTON 100 CMOS
Absorption correction	Multi-scan (SADABS; Bruker, 2012 )
T_min, T_max	0.706, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	64701, 3904, 2539
R_int	0.079
(sin θ/λ)_max (Å⁻¹)	0.668

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.048, 0.125, 1.01
No. of reflections	3904
No. of parameters	221
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.21, −0.21
Computer programs: APEX2 and SAINT (Bruker, 2012), SHELXTL (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ), OLEX2 (Dolomanov et al., 2009 ) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 1979111

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2414314620000711/lh4051sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314620000711/lh4051Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314620000711/lh4051Isup3.cml

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2012); cell refinement: SAINT (Bruker, 2012); data reduction: SAINT (Bruker, 2012); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: publCIF (Westrip, 2010).

(E)-1-(4-Fluoro-2-hydroxyphenyl)-3-(2,3,4-trimethoxyphenyl)prop-2-en-1-one top

Crystal data top

C₁₈H₁₇FO₅	F(000) = 696
M_r = 332.32	D_x = 1.411 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 15.5801 (12) Å	Cell parameters from 9964 reflections
b = 8.3414 (6) Å	θ = 2.8–25.8°
c = 12.1298 (8) Å	µ = 0.11 mm⁻¹
β = 97.086 (3)°	T = 223 K
V = 1564.35 (19) Å³	Block, yellow
Z = 4	0.21 × 0.15 × 0.10 mm

Data collection top

PHOTON 100 CMOS diffractometer	2539 reflections with I > 2σ(I)
φ and ω scans	R_int = 0.079
Absorption correction: multi-scan (SADABS; Bruker, 2012)	θ_max = 28.4°, θ_min = 2.6°
T_min = 0.706, T_max = 0.746	h = −20→20
64701 measured reflections	k = −11→11
3904 independent reflections	l = −16→16

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.048	H-atom parameters constrained
wR(F²) = 0.125	w = 1/[σ²(F_o²) + (0.0473P)² + 0.6183P] where P = (F_o² + 2F_c²)/3
S = 1.01	(Δ/σ)_max = 0.001
3904 reflections	Δρ_max = 0.21 e Å⁻³
221 parameters	Δρ_min = −0.21 e Å⁻³

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.92429 (10)	0.0434 (2)	0.67173 (13)	0.0787 (5)
C1	0.95147 (12)	0.1327 (2)	0.60215 (15)	0.0465 (4)
C2	0.89787 (11)	0.1589 (2)	0.49622 (15)	0.0448 (4)
H2	0.9178	0.2247	0.4418	0.054*
C3	0.82032 (11)	0.0890 (2)	0.47693 (15)	0.0433 (4)
H3	0.8031	0.0297	0.5363	0.052*
C4	0.75915 (10)	0.0924 (2)	0.37646 (14)	0.0406 (4)
C5	0.67961 (11)	0.01064 (19)	0.37400 (14)	0.0387 (4)
C6	0.62259 (10)	0.00211 (19)	0.27734 (14)	0.0384 (4)
C7	0.64306 (11)	0.0776 (2)	0.18080 (15)	0.0415 (4)
C8	0.71985 (12)	0.1619 (2)	0.18280 (16)	0.0487 (4)
H8	0.7334	0.2144	0.1186	0.058*
C9	0.77632 (11)	0.1685 (2)	0.27966 (15)	0.0473 (4)
H9	0.8281	0.2263	0.2802	0.057*
O2	0.65803 (8)	−0.04848 (15)	0.47252 (10)	0.0482 (3)
C10	0.63936 (14)	−0.2150 (2)	0.47998 (17)	0.0563 (5)
H10A	0.5893	−0.2413	0.4275	0.084*
H10B	0.6274	−0.2400	0.5547	0.084*
H10C	0.6887	−0.2770	0.4629	0.084*
O3	0.54649 (7)	−0.08295 (14)	0.27272 (10)	0.0439 (3)
C11	0.47618 (11)	0.0049 (2)	0.30660 (18)	0.0553 (5)
H11A	0.4884	0.0307	0.3849	0.083*
H11B	0.4239	−0.0591	0.2942	0.083*
H11C	0.4682	0.1032	0.2638	0.083*
O4	0.58278 (8)	0.06284 (15)	0.09020 (10)	0.0483 (3)
C12	0.59864 (13)	0.1441 (2)	−0.00904 (16)	0.0544 (5)
H12A	0.6038	0.2583	0.0054	0.082*
H12B	0.5510	0.1248	−0.0669	0.082*
H12C	0.6519	0.1045	−0.0330	0.082*
C13	1.03648 (11)	0.2090 (2)	0.62893 (14)	0.0396 (4)
C14	1.08778 (12)	0.1692 (2)	0.72906 (14)	0.0458 (4)
C15	1.16780 (12)	0.2411 (2)	0.75754 (16)	0.0520 (5)
H15	1.2027	0.2136	0.8237	0.062*
C16	1.19430 (12)	0.3521 (2)	0.68738 (17)	0.0524 (5)
C17	1.14761 (12)	0.3949 (2)	0.58816 (17)	0.0511 (5)
H17	1.1687	0.4717	0.5415	0.061*
C18	1.06905 (11)	0.3214 (2)	0.55947 (15)	0.0444 (4)
H18	1.0364	0.3474	0.4914	0.053*
O5	1.06213 (10)	0.06119 (19)	0.80053 (11)	0.0663 (4)
H5	1.0118	0.0325	0.7789	0.099*
F1	1.27125 (7)	0.42519 (16)	0.71683 (12)	0.0763 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0693 (10)	0.1025 (13)	0.0620 (9)	−0.0386 (9)	−0.0006 (7)	0.0286 (9)
C1	0.0466 (10)	0.0478 (10)	0.0461 (10)	−0.0059 (8)	0.0095 (8)	−0.0009 (8)
C2	0.0420 (10)	0.0458 (10)	0.0476 (10)	−0.0037 (8)	0.0097 (8)	−0.0011 (8)
C3	0.0438 (10)	0.0410 (9)	0.0466 (10)	−0.0025 (8)	0.0109 (8)	−0.0047 (8)
C4	0.0382 (9)	0.0350 (9)	0.0497 (10)	−0.0018 (7)	0.0098 (7)	−0.0059 (7)
C5	0.0398 (9)	0.0323 (8)	0.0457 (9)	0.0000 (7)	0.0116 (7)	−0.0026 (7)
C6	0.0351 (8)	0.0303 (8)	0.0513 (10)	−0.0026 (7)	0.0113 (7)	−0.0024 (7)
C7	0.0404 (9)	0.0342 (9)	0.0500 (10)	−0.0004 (7)	0.0058 (8)	−0.0004 (7)
C8	0.0493 (11)	0.0470 (10)	0.0511 (11)	−0.0080 (8)	0.0114 (8)	0.0073 (8)
C9	0.0407 (10)	0.0451 (10)	0.0573 (11)	−0.0096 (8)	0.0101 (8)	−0.0002 (8)
O2	0.0555 (8)	0.0440 (7)	0.0476 (7)	−0.0117 (6)	0.0156 (6)	−0.0007 (6)
C10	0.0649 (13)	0.0420 (10)	0.0631 (12)	0.0024 (9)	0.0129 (10)	0.0091 (9)
O3	0.0372 (6)	0.0367 (6)	0.0587 (8)	−0.0067 (5)	0.0099 (5)	−0.0018 (5)
C11	0.0367 (10)	0.0583 (12)	0.0718 (13)	0.0030 (9)	0.0097 (9)	0.0003 (10)
O4	0.0483 (7)	0.0467 (7)	0.0491 (7)	−0.0092 (6)	0.0029 (6)	0.0060 (6)
C12	0.0595 (12)	0.0532 (12)	0.0501 (11)	−0.0050 (9)	0.0055 (9)	0.0075 (9)
C13	0.0403 (9)	0.0390 (9)	0.0408 (9)	−0.0008 (7)	0.0104 (7)	−0.0068 (7)
C14	0.0506 (11)	0.0470 (10)	0.0405 (9)	−0.0006 (8)	0.0083 (8)	−0.0064 (8)
C15	0.0484 (11)	0.0561 (12)	0.0495 (10)	0.0023 (9)	−0.0015 (9)	−0.0126 (9)
C16	0.0375 (10)	0.0525 (11)	0.0670 (13)	−0.0040 (8)	0.0058 (9)	−0.0188 (10)
C17	0.0444 (10)	0.0472 (10)	0.0637 (12)	−0.0054 (8)	0.0147 (9)	−0.0005 (9)
C18	0.0407 (9)	0.0450 (10)	0.0482 (10)	−0.0003 (8)	0.0088 (8)	−0.0002 (8)
O5	0.0720 (10)	0.0787 (10)	0.0467 (8)	−0.0169 (8)	0.0016 (7)	0.0116 (7)
F1	0.0467 (7)	0.0820 (9)	0.0978 (10)	−0.0187 (6)	−0.0004 (6)	−0.0190 (8)

Geometric parameters (Å, º) top

O1—C1	1.239 (2)	C10—H10C	0.9700
C1—O1	1.239 (2)	O3—C11	1.420 (2)
C1—C2	1.460 (3)	C11—H11A	0.9700
C1—C13	1.469 (2)	C11—H11B	0.9700
C2—C3	1.336 (2)	C11—H11C	0.9700
C2—H2	0.9400	O4—C12	1.429 (2)
C3—C4	1.452 (2)	C12—H12A	0.9700
C3—H3	0.9400	C12—H12B	0.9700
C4—C9	1.389 (2)	C12—H12C	0.9700
C4—C5	1.412 (2)	C13—C18	1.397 (2)
C5—O2	1.372 (2)	C13—C14	1.409 (2)
C5—C6	1.383 (2)	C14—O5	1.345 (2)
C6—O3	1.3768 (19)	C14—C15	1.388 (3)
C6—C7	1.400 (2)	C15—C16	1.356 (3)
C7—O4	1.360 (2)	C15—H15	0.9400
C7—C8	1.386 (2)	C16—F1	1.353 (2)
C8—C9	1.379 (3)	C16—C17	1.374 (3)
C8—H8	0.9400	C17—C18	1.375 (2)
C9—H9	0.9400	C17—H17	0.9400
O2—C10	1.424 (2)	C18—H18	0.9400
C10—H10A	0.9700	O5—H5	0.8300
C10—H10B	0.9700

O1—C1—C2	118.90 (17)	H10B—C10—H10C	109.5
O1—C1—C2	118.90 (17)	C6—O3—C11	114.41 (13)
O1—C1—C13	118.98 (17)	O3—C11—H11A	109.5
O1—C1—C13	118.98 (17)	O3—C11—H11B	109.5
C2—C1—C13	122.12 (16)	H11A—C11—H11B	109.5
C3—C2—C1	119.70 (17)	O3—C11—H11C	109.5
C3—C2—H2	120.2	H11A—C11—H11C	109.5
C1—C2—H2	120.2	H11B—C11—H11C	109.5
C2—C3—C4	128.64 (17)	C7—O4—C12	117.62 (13)
C2—C3—H3	115.7	O4—C12—H12A	109.5
C4—C3—H3	115.7	O4—C12—H12B	109.5
C9—C4—C5	117.57 (16)	H12A—C12—H12B	109.5
C9—C4—C3	122.92 (15)	O4—C12—H12C	109.5
C5—C4—C3	119.47 (16)	H12A—C12—H12C	109.5
O2—C5—C6	121.26 (15)	H12B—C12—H12C	109.5
O2—C5—C4	117.64 (15)	C18—C13—C14	117.93 (16)
C6—C5—C4	120.89 (15)	C18—C13—C1	122.82 (16)
O3—C6—C5	121.40 (15)	C14—C13—C1	119.25 (16)
O3—C6—C7	118.78 (15)	O5—C14—C15	117.28 (17)
C5—C6—C7	119.80 (15)	O5—C14—C13	122.11 (16)
O4—C7—C8	124.65 (16)	C15—C14—C13	120.61 (17)
O4—C7—C6	115.41 (14)	C16—C15—C14	118.20 (18)
C8—C7—C6	119.93 (16)	C16—C15—H15	120.9
C9—C8—C7	119.58 (17)	C14—C15—H15	120.9
C9—C8—H8	120.2	F1—C16—C15	118.06 (18)
C7—C8—H8	120.2	F1—C16—C17	118.05 (19)
C8—C9—C4	122.19 (16)	C15—C16—C17	123.89 (17)
C8—C9—H9	118.9	C16—C17—C18	117.68 (18)
C4—C9—H9	118.9	C16—C17—H17	121.2
C5—O2—C10	118.67 (14)	C18—C17—H17	121.2
O2—C10—H10A	109.5	C17—C18—C13	121.66 (18)
O2—C10—H10B	109.5	C17—C18—H18	119.2
H10A—C10—H10B	109.5	C13—C18—H18	119.2
O2—C10—H10C	109.5	C14—O5—H5	109.5
H10A—C10—H10C	109.5

O1—O1—C1—C2	0.0 (2)	C6—C5—O2—C10	61.3 (2)
O1—O1—C1—C13	0.0 (3)	C4—C5—O2—C10	−123.86 (17)
O1—C1—C2—C3	1.2 (3)	C5—C6—O3—C11	86.36 (19)
O1—C1—C2—C3	1.2 (3)	C7—C6—O3—C11	−95.34 (19)
C13—C1—C2—C3	−178.72 (16)	C8—C7—O4—C12	−1.9 (2)
C1—C2—C3—C4	−176.61 (17)	C6—C7—O4—C12	177.06 (15)
C2—C3—C4—C9	3.0 (3)	O1—C1—C13—C18	−174.58 (19)
C2—C3—C4—C5	−179.42 (17)	O1—C1—C13—C18	−174.58 (19)
C9—C4—C5—O2	−172.57 (15)	C2—C1—C13—C18	5.3 (3)
C3—C4—C5—O2	9.7 (2)	O1—C1—C13—C14	4.9 (3)
C9—C4—C5—C6	2.3 (2)	O1—C1—C13—C14	4.9 (3)
C3—C4—C5—C6	−175.44 (15)	C2—C1—C13—C14	−175.23 (16)
O2—C5—C6—O3	−8.1 (2)	C18—C13—C14—O5	−179.35 (16)
C4—C5—C6—O3	177.25 (14)	C1—C13—C14—O5	1.1 (3)
O2—C5—C6—C7	173.64 (15)	C18—C13—C14—C15	0.5 (3)
C4—C5—C6—C7	−1.0 (2)	C1—C13—C14—C15	−178.97 (16)
O3—C6—C7—O4	1.9 (2)	O5—C14—C15—C16	−179.04 (17)
C5—C6—C7—O4	−179.78 (14)	C13—C14—C15—C16	1.1 (3)
O3—C6—C7—C8	−179.05 (15)	C14—C15—C16—F1	178.23 (16)
C5—C6—C7—C8	−0.7 (2)	C14—C15—C16—C17	−1.7 (3)
O4—C7—C8—C9	−179.89 (16)	F1—C16—C17—C18	−179.28 (16)
C6—C7—C8—C9	1.1 (3)	C15—C16—C17—C18	0.7 (3)
C7—C8—C9—C4	0.2 (3)	C16—C17—C18—C13	1.0 (3)
C5—C4—C9—C8	−1.9 (3)	C14—C13—C18—C17	−1.6 (3)
C3—C4—C9—C8	175.76 (17)	C1—C13—C18—C17	177.87 (17)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5···O1	0.83	1.77	2.499 (2)	146
C18—H18···O5ⁱ	0.94	2.52	3.279 (2)	138

Symmetry code: (i) x, −y+1/2, z−1/2.

Funding information

The authors acknowledge financial support from the Basic Science Research Program (award No. NRF-2019R1F1A1058747).

References

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