(E)-3-(3,5-Dimeth­oxy­phen­yl)-1-(2-meth­oxy­phen­yl)prop-2-en-1-one

Lim, Y.; Koh, D.

doi:10.1107/S1600536813006302

organic compounds

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ISSN: 2056-9890

Volume 69| Part 4| April 2013| Page o514

doi:10.1107/S1600536813006302

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(E)-3-(3,5-Dimethoxyphenyl)-1-(2-methoxyphenyl)prop-2-en-1-one

Yoongho Lim ^a and Dongsoo Koh ^b ^*

^aDivision of Bioscience and Biotechnology, BMIC, Konkuk University, Seoul 143-701, Republic of Korea, and ^bDepartment of Applied Chemistry, Dongduk Women's University, Seoul 136-714, Republic of Korea
^*Correspondence e-mail: dskoh@dongduk.ac.kr

(Received 22 February 2013; accepted 5 March 2013; online 9 March 2013)

In the title molecule, C₁₈H₁₈O₄, the dihedral angle between the benzene rings is 52.52 (7)°. The C=C bond of the central enone group adopts a trans conformation. The relative conformation of the two double bonds in the enone group is s-transoid. In the crystal, molecules are linked by pairs of weak C—H⋯O hydrogen bonds, forming inversion dimers.

Related literature

For the synthesis and biological properties of chalcone derivatives, see: Shin et al. (2012 ); Hwang et al. (2011 ). For related structures, see: Fun et al. (2012 ); Lee et al. (2012 ); Prasath et al. (2010 ).

Experimental

Crystal data

C₁₈H₁₈O₄
M_r = 298.32
Monoclinic, P 2₁ /c
a = 12.0925 (18) Å
b = 8.4460 (12) Å
c = 15.109 (2) Å
β = 92.340 (3)°
V = 1541.9 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 200 K
0.24 × 0.14 × 0.10 mm

Data collection

Bruker SMART CCD diffractometer
11328 measured reflections
3865 independent reflections
1544 reflections with I > 2σ(I)
R_int = 0.053

Refinement

R[F² > 2σ(F²)] = 0.043
wR(F²) = 0.132
S = 0.81
3865 reflections
202 parameters
H-atom parameters constrained
Δρ_max = 0.21 e Å⁻³
Δρ_min = −0.27 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯O1ⁱ	0.95	2.51	3.457 (3)	172
Symmetry code: (i) -x+1, -y, -z+1.

Data collection: SMART (Bruker, 2000 ); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536813006302/lh5589sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813006302/lh5589Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813006302/lh5589Isup3.cml

checkCIF report

Comment top

Chalcones have an α,β-unsaturated carbonyl (enone) group which connects two aromatic rings at the 1,3-positions. Typically, the conformation of enone system is s-cisoid, in which the C═C and C═O double bonds are cis with respect to each other. Few examples of s-transoid conformations have been reported in the literature (Fun et al., 2012; Prasath et al., 2010). As a part of our studies on the substituent effects of chalcones on structures and biological activities (Shin et al., 2012; Hwang et al., 2011), the crystal structure of title compound has been determined.

The molecular structure of the title compound is shown in Fig. 1. The relative conformation of two double bonds of the central enone group is s-transoid. The trans configuration at the C1═C2 bond is reflected in the O1-C1-C2-C3 torsion angle of -168.7 (2)° compared to the value of -1.1 (5)° in a structure with an s-cisoid configuration (Lee et al., 2012). The dihedral angle between the benzene rings is 52.52 (7)°. Two methoxy groups at meta positions of the C4-C6/C8/C9/C11 ring are essentially co-planar with the ring [C8—C6—O2—C7 = -2.4 (3)° and C11—C9—O3—C10 = -1.2 (3)°]. However, the methoxy group at the ortho position of the C12-C17 ring is slightly twisted with respect to the benzene ring [C16—C17—O4—C18 = 21.6 (3)°]. In the crystal, molecules are linked by a pair of weak C—H···O hydrogen bonds to form inversion dimers (Table 1, Fig. 2).

Related literature top

For the synthesis and biological properties of chalcone derivatives, see: Shin et al. (2012); Hwang et al. (2011). For related structures, see: Fun et al. (2012); Lee et al. (2012); Prasath et al. (2010).

Experimental top

To a solution of 3,5-dimethoxybenzaldehyde (415 mg, 2.5 mmol) in 30 ml of ethanol was added 2-methoxyacetophenone (300 mg, 2 mmol) and the temperature was adjusted to around 276 K in an ice-bath. To the cooled reaction mixture was added 2 ml of 50% aqueous KOH solution, and the reaction mixture was stirred at room temperature for 5 h. This mixture was poured into iced water (50 ml) was acidified (pH = 3) with 3 N HCl solution to give a precipitate. Filtration and washing with water afforded crude solid of the title compound (560 mg, 94%). Recrystallization of the solid in ethanol gave single crystals (mp: 353–355 K).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound, showing displacement ellipsoids drawn at the 50% probability level.
	Fig. 2. Part of the crystal structure showing an inversion dimer formed via a pair of weak intermolecular C—H···O hydrogen bonds shown as dashed lines.

(E)-3-(3,5-Dimethoxyphenyl)-1-(2-methoxyphenyl)prop-2-en-1-one top

Crystal data top

C₁₈H₁₈O₄	F(000) = 632
M_r = 298.32	D_x = 1.285 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2539 reflections
a = 12.0925 (18) Å	θ = 2.7–28.1°
b = 8.4460 (12) Å	µ = 0.09 mm⁻¹
c = 15.109 (2) Å	T = 200 K
β = 92.340 (3)°	Block, colorless
V = 1541.9 (4) Å³	0.24 × 0.14 × 0.10 mm
Z = 4

Data collection top

Bruker SMART CCD diffractometer	1544 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.053
Graphite monochromator	θ_max = 28.5°, θ_min = 1.7°
ϕ and ω scans	h = −16→14
11328 measured reflections	k = −11→10
3865 independent reflections	l = −20→19

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.132	H-atom parameters constrained
S = 0.81	w = 1/[σ²(F_o²) + (0.0575P)²] where P = (F_o² + 2F_c²)/3
3865 reflections	(Δ/σ)_max < 0.001
202 parameters	Δρ_max = 0.21 e Å⁻³
0 restraints	Δρ_min = −0.27 e Å⁻³

Crystal data top

C₁₈H₁₈O₄	V = 1541.9 (4) Å³
M_r = 298.32	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 12.0925 (18) Å	µ = 0.09 mm⁻¹
b = 8.4460 (12) Å	T = 200 K
c = 15.109 (2) Å	0.24 × 0.14 × 0.10 mm
β = 92.340 (3)°

Data collection top

Bruker SMART CCD diffractometer	1544 reflections with I > 2σ(I)
11328 measured reflections	R_int = 0.053
3865 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.043	0 restraints
wR(F²) = 0.132	H-atom parameters constrained
S = 0.81	Δρ_max = 0.21 e Å⁻³
3865 reflections	Δρ_min = −0.27 e Å⁻³
202 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. 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) top

	x	y	z	U_iso*/U_eq
C1	0.40664 (18)	0.2012 (2)	0.41632 (14)	0.0370 (5)
O1	0.35034 (13)	0.11209 (19)	0.46017 (11)	0.0569 (5)
C2	0.52596 (18)	0.2050 (2)	0.43027 (13)	0.0366 (5)
H2	0.5597	0.1242	0.4658	0.044*
C3	0.59125 (17)	0.3144 (2)	0.39646 (13)	0.0359 (5)
H3	0.5557	0.3937	0.3609	0.043*
C4	0.71093 (17)	0.3259 (2)	0.40791 (14)	0.0352 (5)
C5	0.77006 (18)	0.2441 (2)	0.47412 (14)	0.0371 (5)
H5	0.7322	0.1807	0.5151	0.045*
C6	0.88426 (18)	0.2553 (2)	0.48006 (14)	0.0378 (5)
O2	0.93429 (13)	0.17546 (17)	0.54903 (10)	0.0498 (4)
C7	1.05199 (19)	0.1787 (3)	0.55712 (17)	0.0562 (7)
H7A	1.0827	0.1313	0.5043	0.084*
H7B	1.0770	0.1186	0.6097	0.084*
H7C	1.0773	0.2886	0.5630	0.084*
C8	0.94020 (17)	0.3433 (2)	0.41983 (14)	0.0384 (5)
H8	1.0187	0.3496	0.4239	0.046*
C9	0.88069 (18)	0.4234 (2)	0.35258 (15)	0.0379 (5)
O3	0.94471 (12)	0.50354 (18)	0.29569 (11)	0.0518 (5)
C10	0.8906 (2)	0.5865 (3)	0.22476 (16)	0.0587 (7)
H10A	0.8456	0.5124	0.1887	0.088*
H10B	0.9459	0.6359	0.1880	0.088*
H10C	0.8427	0.6685	0.2485	0.088*
C11	0.76750 (17)	0.4184 (2)	0.34780 (14)	0.0359 (5)
H11	0.7275	0.4778	0.3037	0.043*
C12	0.34924 (17)	0.3117 (2)	0.35221 (13)	0.0341 (5)
C13	0.26908 (18)	0.4123 (2)	0.38312 (14)	0.0392 (5)
H13	0.2521	0.4093	0.4439	0.047*
C14	0.21334 (18)	0.5168 (2)	0.32693 (15)	0.0427 (6)
H14	0.1595	0.5868	0.3490	0.051*
C15	0.23697 (18)	0.5181 (2)	0.23841 (15)	0.0426 (6)
H15	0.1986	0.5893	0.1994	0.051*
C16	0.31528 (18)	0.4178 (2)	0.20554 (14)	0.0399 (6)
H16	0.3303	0.4193	0.1443	0.048*
C17	0.37188 (17)	0.3148 (2)	0.26260 (14)	0.0351 (5)
O4	0.44767 (12)	0.20606 (17)	0.23581 (9)	0.0440 (4)
C18	0.4977 (2)	0.2339 (3)	0.15387 (16)	0.0613 (8)
H18A	0.4430	0.2171	0.1051	0.092*
H18B	0.5597	0.1605	0.1477	0.092*
H18C	0.5249	0.3431	0.1522	0.092*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0341 (13)	0.0409 (13)	0.0364 (12)	−0.0028 (10)	0.0042 (10)	0.0045 (10)
O1	0.0405 (10)	0.0666 (11)	0.0637 (11)	−0.0077 (8)	0.0019 (8)	0.0290 (9)
C2	0.0336 (13)	0.0404 (13)	0.0357 (12)	0.0040 (10)	0.0005 (10)	0.0056 (10)
C3	0.0343 (13)	0.0366 (12)	0.0369 (12)	0.0016 (9)	0.0009 (10)	0.0009 (10)
C4	0.0357 (13)	0.0331 (11)	0.0371 (12)	0.0008 (10)	0.0051 (10)	−0.0023 (10)
C5	0.0377 (14)	0.0385 (12)	0.0350 (12)	0.0012 (10)	−0.0012 (10)	0.0049 (10)
C6	0.0405 (14)	0.0335 (12)	0.0388 (13)	0.0078 (10)	−0.0064 (11)	0.0005 (10)
O2	0.0446 (10)	0.0522 (10)	0.0517 (10)	0.0050 (8)	−0.0108 (8)	0.0071 (8)
C7	0.0429 (16)	0.0523 (15)	0.0717 (18)	0.0036 (12)	−0.0198 (13)	0.0017 (13)
C8	0.0283 (12)	0.0369 (12)	0.0497 (14)	0.0034 (10)	−0.0019 (10)	−0.0016 (11)
C9	0.0355 (13)	0.0327 (12)	0.0460 (14)	−0.0014 (10)	0.0087 (11)	0.0003 (10)
O3	0.0360 (10)	0.0558 (10)	0.0642 (11)	0.0011 (8)	0.0085 (8)	0.0177 (9)
C10	0.0510 (17)	0.0658 (17)	0.0600 (17)	0.0020 (13)	0.0098 (14)	0.0228 (14)
C11	0.0307 (13)	0.0341 (12)	0.0428 (13)	0.0019 (9)	0.0014 (10)	0.0018 (10)
C12	0.0317 (12)	0.0335 (11)	0.0374 (12)	−0.0039 (9)	0.0030 (10)	0.0025 (10)
C13	0.0375 (13)	0.0433 (13)	0.0370 (12)	−0.0041 (10)	0.0044 (10)	0.0006 (11)
C14	0.0348 (13)	0.0378 (13)	0.0555 (16)	0.0000 (10)	0.0036 (11)	−0.0028 (12)
C15	0.0350 (13)	0.0393 (13)	0.0530 (15)	−0.0023 (10)	−0.0050 (11)	0.0091 (11)
C16	0.0413 (14)	0.0417 (13)	0.0364 (13)	−0.0043 (11)	0.0002 (11)	0.0060 (11)
C17	0.0318 (12)	0.0348 (12)	0.0389 (13)	−0.0020 (10)	0.0040 (10)	−0.0005 (10)
O4	0.0471 (10)	0.0489 (9)	0.0363 (9)	0.0096 (7)	0.0061 (7)	0.0007 (7)
C18	0.0630 (19)	0.0699 (17)	0.0529 (16)	0.0118 (14)	0.0248 (14)	0.0074 (14)

Geometric parameters (Å, º) top

C1—O1	1.227 (2)	O3—C10	1.418 (3)
C1—C2	1.450 (3)	C10—H10A	0.9800
C1—C12	1.496 (3)	C10—H10B	0.9800
C2—C3	1.331 (3)	C10—H10C	0.9800
C2—H2	0.9500	C11—H11	0.9500
C3—C4	1.454 (3)	C12—C13	1.384 (3)
C3—H3	0.9500	C12—C17	1.392 (3)
C4—C5	1.390 (3)	C13—C14	1.381 (3)
C4—C11	1.398 (3)	C13—H13	0.9500
C5—C6	1.384 (3)	C14—C15	1.379 (3)
C5—H5	0.9500	C14—H14	0.9500
C6—O2	1.362 (2)	C15—C16	1.378 (3)
C6—C8	1.374 (3)	C15—H15	0.9500
O2—C7	1.424 (3)	C16—C17	1.386 (3)
C7—H7A	0.9800	C16—H16	0.9500
C7—H7B	0.9800	C17—O4	1.370 (2)
C7—H7C	0.9800	O4—C18	1.420 (2)
C8—C9	1.396 (3)	C18—H18A	0.9800
C8—H8	0.9500	C18—H18B	0.9800
C9—O3	1.361 (2)	C18—H18C	0.9800
C9—C11	1.368 (3)

O1—C1—C2	120.4 (2)	O3—C10—H10B	109.5
O1—C1—C12	118.7 (2)	H10A—C10—H10B	109.5
C2—C1—C12	120.86 (18)	O3—C10—H10C	109.5
C3—C2—C1	124.2 (2)	H10A—C10—H10C	109.5
C3—C2—H2	117.9	H10B—C10—H10C	109.5
C1—C2—H2	117.9	C9—C11—C4	119.8 (2)
C2—C3—C4	127.2 (2)	C9—C11—H11	120.1
C2—C3—H3	116.4	C4—C11—H11	120.1
C4—C3—H3	116.4	C13—C12—C17	119.01 (19)
C5—C4—C11	119.6 (2)	C13—C12—C1	118.51 (18)
C5—C4—C3	122.21 (19)	C17—C12—C1	122.46 (18)
C11—C4—C3	118.11 (19)	C14—C13—C12	121.0 (2)
C6—C5—C4	119.7 (2)	C14—C13—H13	119.5
C6—C5—H5	120.1	C12—C13—H13	119.5
C4—C5—H5	120.1	C15—C14—C13	119.1 (2)
O2—C6—C8	124.0 (2)	C15—C14—H14	120.5
O2—C6—C5	115.25 (19)	C13—C14—H14	120.5
C8—C6—C5	120.7 (2)	C16—C15—C14	121.1 (2)
C6—O2—C7	117.86 (18)	C16—C15—H15	119.4
O2—C7—H7A	109.5	C14—C15—H15	119.4
O2—C7—H7B	109.5	C15—C16—C17	119.4 (2)
H7A—C7—H7B	109.5	C15—C16—H16	120.3
O2—C7—H7C	109.5	C17—C16—H16	120.3
H7A—C7—H7C	109.5	O4—C17—C16	123.80 (18)
H7B—C7—H7C	109.5	O4—C17—C12	115.80 (18)
C6—C8—C9	119.4 (2)	C16—C17—C12	120.32 (19)
C6—C8—H8	120.3	C17—O4—C18	117.45 (17)
C9—C8—H8	120.3	O4—C18—H18A	109.5
O3—C9—C11	125.1 (2)	O4—C18—H18B	109.5
O3—C9—C8	114.3 (2)	H18A—C18—H18B	109.5
C11—C9—C8	120.6 (2)	O4—C18—H18C	109.5
C9—O3—C10	117.80 (18)	H18A—C18—H18C	109.5
O3—C10—H10A	109.5	H18B—C18—H18C	109.5

O1—C1—C2—C3	−168.7 (2)	C5—C4—C11—C9	2.3 (3)
C12—C1—C2—C3	7.7 (3)	C3—C4—C11—C9	−175.44 (19)
C1—C2—C3—C4	179.76 (19)	O1—C1—C12—C13	54.6 (3)
C2—C3—C4—C5	−16.2 (3)	C2—C1—C12—C13	−121.9 (2)
C2—C3—C4—C11	161.5 (2)	O1—C1—C12—C17	−124.0 (2)
C11—C4—C5—C6	0.2 (3)	C2—C1—C12—C17	59.4 (3)
C3—C4—C5—C6	177.85 (19)	C17—C12—C13—C14	−1.3 (3)
C4—C5—C6—O2	177.74 (18)	C1—C12—C13—C14	−180.0 (2)
C4—C5—C6—C8	−1.7 (3)	C12—C13—C14—C15	1.2 (3)
C8—C6—O2—C7	−2.4 (3)	C13—C14—C15—C16	−0.3 (3)
C5—C6—O2—C7	178.19 (18)	C14—C15—C16—C17	−0.5 (3)
O2—C6—C8—C9	−178.67 (19)	C15—C16—C17—O4	177.12 (19)
C5—C6—C8—C9	0.7 (3)	C15—C16—C17—C12	0.5 (3)
C6—C8—C9—O3	−178.56 (18)	C13—C12—C17—O4	−176.49 (17)
C6—C8—C9—C11	1.9 (3)	C1—C12—C17—O4	2.1 (3)
C11—C9—O3—C10	−1.2 (3)	C13—C12—C17—C16	0.4 (3)
C8—C9—O3—C10	179.24 (19)	C1—C12—C17—C16	179.03 (19)
O3—C9—C11—C4	177.11 (18)	C16—C17—O4—C18	21.6 (3)
C8—C9—C11—C4	−3.4 (3)	C12—C17—O4—C18	−161.6 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O1ⁱ	0.95	2.51	3.457 (3)	172

Symmetry code: (i) −x+1, −y, −z+1.

Experimental details

Crystal data
Chemical formula	C₁₈H₁₈O₄
M_r	298.32
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	200
a, b, c (Å)	12.0925 (18), 8.4460 (12), 15.109 (2)
β (°)	92.340 (3)
V (Å³)	1541.9 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.24 × 0.14 × 0.10

Data collection
Diffractometer	Bruker SMART CCD diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	11328, 3865, 1544
R_int	0.053
(sin θ/λ)_max (Å⁻¹)	0.670

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.043, 0.132, 0.81
No. of reflections	3865
No. of parameters	202
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.21, −0.27

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O1ⁱ	0.95	2.51	3.457 (3)	171.8

Symmetry code: (i) −x+1, −y, −z+1.

References

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Volume 69| Part 4| April 2013| Page o514

doi:10.1107/S1600536813006302

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