(E)-1-(2-Hy­droxy-6-meth­oxy­phen­yl)-3-(2-meth­oxy­naphthalen-1-yl)prop-2-en-1-one

Sung, J.

doi:10.1107/S2414314619012811

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 4| Part 9| September 2019| x191281

https://doi.org/10.1107/S2414314619012811

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(E)-1-(2-Hydroxy-6-methoxyphenyl)-3-(2-methoxynaphthalen-1-yl)prop-2-en-1-one

Jiha Sung ^a ^*

^aDepartment of Applied Chemistry, Dongduk Women's University, Seoul 136-714, Republic of Korea
^*Correspondence e-mail: dddklab@gmail.com

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 3 September 2019; accepted 16 September 2019; online 27 September 2019)

In the title compound, C₂₁H₁₈O₄, the dihedral angle between the naphthelene ring system (r.m.s. deviation = 0.014 Å) and the benzene ring is 9.68 (1)°. The C atom of the methoxy group of the naphthalene ring system is almost coplanar with the ring [C—O—C—C = −2.0 (3)°], whereas the C atom of the methoxy group of the phenol ring is slightly twisted [C—O—C—C = 6.2 (3)°]. An intramolecular O—H⋯O hydrogen bond generates an S(6) ring motif.

Keywords: crystal structure; chalcone; flavonoid; O—H⋯O hydrogen bonds.

CCDC reference: 1953849

Structure description

Chalcones are a family of flavonoids which have a general C6–C3–C6 carbon framework. In contrast to other flavonoid families, chalcones possess the C3 unit as an α, β-unsaturated carbonyl (enone) group. In the enone system, the C=C and C=O double bonds are in a cis conformation along with a single bond connecting the two double bonds (s-cisoid). According to recent reviews (Mahapatra et al., 2019 ; Zhuang et al., 2017 ), natural and synthetic chalcones reveal diverse biological activities. In addition, when a chalcone has a hydroxyl group adjacent to carbonyl group, it tends to react via an intramolecular Michael addition to form flavanone, flavone or flavonol derivatives depending on the reaction conditions. The crystal structure of a flavone derived from hydroxyl-chalcone was described recently (Sung, 2018 ). In continuation of our work in this area (Ahn et al., 2017 ), the title compound was synthesized and its crystal structure was determined and are reported here.

The molecular structure of the title compound is shown in Fig. 1. The C2=C3 double bond of the central enone group adopts a trans configuration [H2—C2—C3—H3 = −179.2°]. In the enone system, the C=C double bond and C=O double bond are not in the same plane [torsion angle O1—C1—C2—C3 = −17.6 (3)°]. The C atom of the methoxy group of the naphthalene ring is almost coplanar with the ring [C14—O2—C5—C6 = −2.0 (3)°], whereas the C atom of the methoxy group of the benzene ring is slightly twisted [C21—O4—C20—C19 = 6.2 (3)°]. The dihedral angle formed between the plane of the naphthalene ring system (C4–C13; r.m.s. deviation = 0.014 Å) and the plane of the benzene ring (C15–C20; r.m.s. deviation = 0.006 Å) is 9.68 (1)°. An intramolecular O—H⋯O hydrogen bonds generates an S(6) ring motif. (Table 1).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3A⋯O1	0.84	1.72	2.473 (2)	147

Figure 1
The molecular structure of the title compound with displacement ellipsoids drawn at the 30% probability level.

Synthesis and crystallization

2-Hydroxy-6-methoxyacetophenone (830 mg, 5 mmol) was added to a solution of 2-methoxynaphthaldehyde (930 mg, 5 mmol) in 80 ml of ethanol (Fig. 2) and the temperature was adjusted to around 275–276 K in an ice-bath. To the cooled reaction mixture, 7 ml of 50% aqueous KOH solution were added, and the reaction mixture was stirred at room temperature for 20 h. This mixture was poured into iced water (150 ml) and was acidified (pH = 3) with 6 N HCl solution to give a precipitate. Filtration and washing with water afforded the crude solid of the title compound (802 mg, 48%). Recrystallization of the solid from ethanol solution gave orange blocks suitable for X-ray diffraction analysis (m.p. 472–473 K).

Figure 2
Synthetic scheme for the preparation of the title compound.

Refinement

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

Table 2
Experimental details

Crystal data
Chemical formula	C₂₁H₁₈O₄
M_r	334.35
Crystal system, space group	Orthorhombic, Pna2₁
Temperature (K)	200
a, b, c (Å)	14.8220 (9), 5.2416 (3), 20.8364 (13)
V (Å³)	1618.80 (17)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.10
Crystal size (mm)	0.25 × 0.15 × 0.07

Data collection
Diffractometer	Bruker CCD area detector
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	11076, 2853, 2041
R_int	0.050
(sin θ/λ)_max (Å⁻¹)	0.667

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.088, 1.04
No. of reflections	2853
No. of parameters	229
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.21, −0.20
Computer programs: APEX2 (Bruker, 2012 ), SAINT (Bruker, 2012), SHELXS (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ), SHELXTL (Sheldrick, 2008), publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 1953849

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2414314619012811/hb4318sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314619012811/hb4318Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314619012811/hb4318Isup3.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: SHELXS (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: publCIF (Westrip, 2010).

(E)-1-(2-Hydroxy-6-methoxyphenyl)-3-(2-methoxynaphthalen-1-yl)prop-2-en-1-one top

Crystal data top

C₂₁H₁₈O₄	F(000) = 704
M_r = 334.35	D_x = 1.372 Mg m⁻³
Orthorhombic, Pna2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2n	Cell parameters from 4201 reflections
a = 14.8220 (9) Å	θ = 2.8–27.4°
b = 5.2416 (3) Å	µ = 0.10 mm⁻¹
c = 20.8364 (13) Å	T = 200 K
V = 1618.80 (17) Å³	Block, orange
Z = 4	0.25 × 0.15 × 0.07 mm

Data collection top

Bruker CCD area detector diffractometer	2041 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.050
Graphite monochromator	θ_max = 28.3°, θ_min = 2.0°
phi and ω scans	h = −19→19
11076 measured reflections	k = −6→6
2853 independent reflections	l = −27→11

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)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.088	H-atom parameters constrained
S = 1.03	w = 1/[σ²(F_o²) + (0.0346P)²] where P = (F_o² + 2F_c²)/3
2853 reflections	(Δ/σ)_max < 0.001
229 parameters	Δρ_max = 0.21 e Å⁻³
1 restraint	Δρ_min = −0.20 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.

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 > 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

	x	y	z	U_iso*/U_eq
C1	0.60597 (14)	0.4619 (4)	0.12953 (12)	0.0341 (5)
O1	0.67919 (11)	0.3449 (3)	0.13586 (9)	0.0469 (5)
C2	0.59032 (15)	0.6894 (4)	0.16954 (12)	0.0336 (5)
H2	0.5448	0.8089	0.1583	0.040*
C3	0.64120 (15)	0.7258 (4)	0.22208 (12)	0.0330 (5)
H3	0.6855	0.5981	0.2293	0.040*
C4	0.63973 (15)	0.9290 (4)	0.27004 (12)	0.0328 (5)
C5	0.56895 (16)	1.1025 (4)	0.27589 (12)	0.0350 (5)
C6	0.56880 (17)	1.2901 (5)	0.32383 (13)	0.0407 (6)
H6	0.5193	1.4046	0.3270	0.049*
C7	0.63881 (17)	1.3101 (5)	0.36588 (12)	0.0405 (6)
H7	0.6379	1.4399	0.3977	0.049*
C8	0.71243 (16)	1.1411 (4)	0.36284 (11)	0.0360 (6)
C9	0.78445 (17)	1.1583 (5)	0.40781 (13)	0.0421 (6)
H9	0.7836	1.2895	0.4393	0.051*
C10	0.85437 (17)	0.9906 (5)	0.40658 (14)	0.0463 (7)
H10	0.9016	1.0026	0.4372	0.056*
C11	0.85583 (18)	0.7997 (5)	0.35945 (13)	0.0451 (7)
H11	0.9045	0.6817	0.3586	0.054*
C12	0.78887 (16)	0.7799 (5)	0.31489 (13)	0.0386 (6)
H12	0.7927	0.6515	0.2828	0.046*
C13	0.71324 (16)	0.9479 (4)	0.31534 (12)	0.0325 (5)
O2	0.49958 (11)	1.0813 (3)	0.23328 (9)	0.0441 (4)
C14	0.42411 (16)	1.2514 (4)	0.23981 (15)	0.0441 (6)
H14A	0.3956	1.2251	0.2817	0.066*
H14B	0.3802	1.2168	0.2057	0.066*
H14C	0.4451	1.4282	0.2364	0.066*
C15	0.53979 (15)	0.3670 (4)	0.08228 (11)	0.0313 (5)
C16	0.56510 (15)	0.1617 (4)	0.04161 (12)	0.0345 (5)
O3	0.64746 (11)	0.0559 (3)	0.04480 (9)	0.0463 (5)
H3A	0.6755	0.1164	0.0763	0.069*
C17	0.50611 (17)	0.0633 (5)	−0.00367 (13)	0.0418 (6)
H17	0.5247	−0.0727	−0.0308	0.050*
C18	0.42135 (19)	0.1621 (5)	−0.00917 (13)	0.0470 (7)
H18	0.3815	0.0945	−0.0406	0.056*
C19	0.39205 (16)	0.3592 (5)	0.03002 (13)	0.0406 (6)
H19	0.3325	0.4243	0.0257	0.049*
C20	0.44987 (16)	0.4601 (4)	0.07524 (12)	0.0344 (5)
O4	0.42414 (10)	0.6504 (3)	0.11552 (9)	0.0424 (4)
C21	0.33232 (16)	0.7297 (5)	0.11503 (16)	0.0550 (8)
H21A	0.3165	0.7922	0.0722	0.082*
H21B	0.3237	0.8666	0.1465	0.082*
H21C	0.2935	0.5849	0.1261	0.082*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0301 (12)	0.0399 (13)	0.0324 (14)	−0.0034 (10)	0.0024 (10)	−0.0007 (11)
O1	0.0320 (9)	0.0572 (11)	0.0516 (12)	0.0068 (8)	−0.0050 (8)	−0.0143 (10)
C2	0.0308 (12)	0.0363 (13)	0.0337 (14)	−0.0020 (9)	0.0016 (11)	−0.0022 (11)
C3	0.0292 (12)	0.0351 (12)	0.0348 (14)	−0.0029 (9)	0.0012 (11)	0.0003 (11)
C4	0.0342 (13)	0.0333 (12)	0.0310 (13)	−0.0041 (10)	0.0030 (11)	−0.0003 (11)
C5	0.0348 (13)	0.0386 (13)	0.0316 (13)	−0.0040 (10)	0.0030 (11)	−0.0002 (11)
C6	0.0437 (15)	0.0380 (14)	0.0404 (15)	0.0017 (11)	0.0066 (13)	−0.0008 (12)
C7	0.0515 (16)	0.0378 (14)	0.0323 (15)	−0.0056 (12)	0.0058 (13)	−0.0052 (11)
C8	0.0434 (14)	0.0366 (13)	0.0280 (14)	−0.0101 (10)	0.0040 (11)	0.0025 (11)
C9	0.0530 (16)	0.0431 (14)	0.0302 (13)	−0.0134 (12)	−0.0019 (13)	0.0012 (12)
C10	0.0502 (17)	0.0494 (16)	0.0392 (16)	−0.0134 (12)	−0.0126 (14)	0.0093 (14)
C11	0.0451 (16)	0.0381 (14)	0.0521 (19)	−0.0074 (11)	−0.0118 (13)	0.0055 (13)
C12	0.0405 (14)	0.0335 (12)	0.0416 (15)	−0.0054 (11)	−0.0066 (12)	0.0001 (12)
C13	0.0361 (13)	0.0321 (11)	0.0292 (12)	−0.0065 (10)	0.0012 (10)	0.0023 (11)
O2	0.0382 (9)	0.0487 (10)	0.0454 (11)	0.0100 (8)	−0.0047 (8)	−0.0078 (9)
C14	0.0355 (15)	0.0458 (14)	0.0511 (17)	0.0066 (11)	0.0009 (12)	0.0012 (14)
C15	0.0310 (12)	0.0362 (12)	0.0268 (13)	−0.0020 (10)	0.0017 (10)	−0.0007 (11)
C16	0.0361 (13)	0.0359 (12)	0.0315 (14)	0.0000 (10)	0.0022 (11)	0.0006 (11)
O3	0.0414 (10)	0.0532 (11)	0.0443 (12)	0.0087 (8)	−0.0011 (9)	−0.0117 (9)
C17	0.0493 (16)	0.0426 (14)	0.0335 (15)	−0.0026 (12)	−0.0002 (13)	−0.0071 (12)
C18	0.0523 (18)	0.0531 (15)	0.0355 (16)	−0.0089 (13)	−0.0113 (13)	−0.0088 (13)
C19	0.0336 (13)	0.0476 (14)	0.0406 (16)	0.0000 (11)	−0.0062 (12)	0.0008 (13)
C20	0.0352 (13)	0.0354 (12)	0.0326 (13)	−0.0021 (10)	0.0009 (11)	−0.0006 (11)
O4	0.0292 (8)	0.0507 (10)	0.0472 (11)	0.0045 (7)	−0.0037 (8)	−0.0137 (9)
C21	0.0328 (13)	0.0661 (18)	0.066 (2)	0.0101 (12)	−0.0014 (15)	−0.0152 (17)

Geometric parameters (Å, º) top

C1—O1	1.254 (3)	C11—H11	0.9500
C1—O1	1.254 (3)	C12—C13	1.425 (3)
C1—C2	1.473 (3)	C12—H12	0.9500
C1—C15	1.476 (3)	O2—C14	1.437 (3)
C2—C3	1.343 (3)	C14—H14A	0.9800
C2—H2	0.9500	C14—H14B	0.9800
C3—C4	1.461 (3)	C14—H14C	0.9800
C3—H3	0.9500	C15—C16	1.420 (3)
C4—C5	1.394 (3)	C15—C20	1.427 (3)
C4—C13	1.445 (3)	C16—O3	1.343 (3)
C5—O2	1.363 (3)	C16—C17	1.386 (3)
C5—C6	1.402 (3)	O3—H3A	0.8400
C6—C7	1.362 (3)	C17—C18	1.364 (4)
C6—H6	0.9500	C17—H17	0.9500
C7—C8	1.407 (3)	C18—C19	1.386 (4)
C7—H7	0.9500	C18—H18	0.9500
C8—C13	1.416 (3)	C19—C20	1.379 (3)
C8—C9	1.423 (3)	C19—H19	0.9500
C9—C10	1.359 (3)	C20—O4	1.358 (3)
C9—H9	0.9500	O4—C21	1.423 (3)
C10—C11	1.402 (4)	C21—H21A	0.9800
C10—H10	0.9500	C21—H21B	0.9800
C11—C12	1.363 (3)	C21—H21C	0.9800

O1—C1—C2	118.2 (2)	C13—C12—H12	119.3
O1—C1—C2	118.2 (2)	C8—C13—C12	116.9 (2)
O1—C1—C15	118.7 (2)	C8—C13—C4	119.9 (2)
O1—C1—C15	118.7 (2)	C12—C13—C4	123.1 (2)
C2—C1—C15	123.1 (2)	C5—O2—C14	118.36 (19)
C3—C2—C1	119.2 (2)	O2—C14—H14A	109.5
C3—C2—H2	120.4	O2—C14—H14B	109.5
C1—C2—H2	120.4	H14A—C14—H14B	109.5
C2—C3—C4	130.8 (2)	O2—C14—H14C	109.5
C2—C3—H3	114.6	H14A—C14—H14C	109.5
C4—C3—H3	114.6	H14B—C14—H14C	109.5
C5—C4—C13	117.8 (2)	C16—C15—C20	116.4 (2)
C5—C4—C3	123.2 (2)	C16—C15—C1	118.6 (2)
C13—C4—C3	119.05 (19)	C20—C15—C1	125.0 (2)
O2—C5—C4	117.2 (2)	O3—C16—C17	117.0 (2)
O2—C5—C6	121.4 (2)	O3—C16—C15	121.6 (2)
C4—C5—C6	121.4 (2)	C17—C16—C15	121.4 (2)
C7—C6—C5	120.7 (2)	C16—O3—H3A	109.5
C7—C6—H6	119.6	C18—C17—C16	119.8 (2)
C5—C6—H6	119.6	C18—C17—H17	120.1
C6—C7—C8	120.9 (2)	C16—C17—H17	120.1
C6—C7—H7	119.5	C17—C18—C19	121.5 (2)
C8—C7—H7	119.5	C17—C18—H18	119.3
C7—C8—C13	119.2 (2)	C19—C18—H18	119.3
C7—C8—C9	120.8 (2)	C20—C19—C18	119.6 (2)
C13—C8—C9	119.9 (2)	C20—C19—H19	120.2
C10—C9—C8	121.2 (2)	C18—C19—H19	120.2
C10—C9—H9	119.4	O4—C20—C19	122.0 (2)
C8—C9—H9	119.4	O4—C20—C15	116.7 (2)
C9—C10—C11	119.1 (2)	C19—C20—C15	121.3 (2)
C9—C10—H10	120.4	C20—O4—C21	118.59 (19)
C11—C10—H10	120.4	O4—C21—H21A	109.5
C12—C11—C10	121.3 (2)	O4—C21—H21B	109.5
C12—C11—H11	119.3	H21A—C21—H21B	109.5
C10—C11—H11	119.3	O4—C21—H21C	109.5
C11—C12—C13	121.4 (2)	H21A—C21—H21C	109.5
C11—C12—H12	119.3	H21B—C21—H21C	109.5

C2—C1—O1—O1	0.00 (5)	C5—C4—C13—C8	−1.1 (3)
C15—C1—O1—O1	0.00 (6)	C3—C4—C13—C8	−179.0 (2)
O1—C1—C2—C3	−17.6 (3)	C5—C4—C13—C12	179.2 (2)
O1—C1—C2—C3	−17.6 (3)	C3—C4—C13—C12	1.3 (3)
C15—C1—C2—C3	162.7 (2)	C4—C5—O2—C14	177.6 (2)
C1—C2—C3—C4	−179.2 (2)	C6—C5—O2—C14	−2.0 (3)
C2—C3—C4—C5	13.8 (4)	O1—C1—C15—C16	−5.9 (3)
C2—C3—C4—C13	−168.4 (2)	O1—C1—C15—C16	−5.9 (3)
C13—C4—C5—O2	−179.4 (2)	C2—C1—C15—C16	173.7 (2)
C3—C4—C5—O2	−1.6 (3)	O1—C1—C15—C20	171.9 (2)
C13—C4—C5—C6	0.2 (3)	O1—C1—C15—C20	171.9 (2)
C3—C4—C5—C6	178.0 (2)	C2—C1—C15—C20	−8.4 (3)
O2—C5—C6—C7	−179.6 (2)	C20—C15—C16—O3	−178.8 (2)
C4—C5—C6—C7	0.8 (4)	C1—C15—C16—O3	−0.8 (3)
C5—C6—C7—C8	−0.9 (4)	C20—C15—C16—C17	1.8 (3)
C6—C7—C8—C13	−0.1 (3)	C1—C15—C16—C17	179.9 (2)
C6—C7—C8—C9	−178.4 (2)	O3—C16—C17—C18	179.8 (2)
C7—C8—C9—C10	177.8 (2)	C15—C16—C17—C18	−0.8 (4)
C13—C8—C9—C10	−0.6 (3)	C16—C17—C18—C19	−0.5 (4)
C8—C9—C10—C11	0.9 (4)	C17—C18—C19—C20	0.7 (4)
C9—C10—C11—C12	0.3 (4)	C18—C19—C20—O4	−178.9 (2)
C10—C11—C12—C13	−1.8 (4)	C18—C19—C20—C15	0.5 (4)
C7—C8—C13—C12	−179.2 (2)	C16—C15—C20—O4	177.75 (19)
C9—C8—C13—C12	−0.9 (3)	C1—C15—C20—O4	−0.1 (3)
C7—C8—C13—C4	1.1 (3)	C16—C15—C20—C19	−1.7 (3)
C9—C8—C13—C4	179.4 (2)	C1—C15—C20—C19	−179.5 (2)
C11—C12—C13—C8	2.0 (3)	C19—C20—O4—C21	6.2 (3)
C11—C12—C13—C4	−178.3 (2)	C15—C20—O4—C21	−173.2 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O1	0.84	1.72	2.473 (2)	147

Acknowledgements

The author acknowledges financial support from Dongduk Women's University.

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