organic compounds
3-(2,3-Dimethoxyphenyl)-2,3-dihydro-1H-benzo[f]chromen-1-one
aDepartment of Applied Chemistry, Dongduk Women's University, Seoul 136-714, Republic of Korea
*Correspondence e-mail: dddklab@gmail.com
In the title compound, C21H18O4, the central pyran ring is in an and the dihedral angle between the benzene ring and naphthalene ring system is 88.31 (1)°. The methoxy groups at the ortho and meta positions of the benzene ring are tilted to the ring with C—C—O—C torsion angles of 105.9 (4) and 9.5 (5)°, respectively. In the crystal, pairwise C—H⋯O hydrogen bonds form R22(14) inversion dimers, which are linked by another pair of C—H⋯O hydrogen bonds to form [210] chains in the crystal.
Keywords: crystal structure; flavanone; benzochromenone; C—H⋯O hydrogen bonds.
CCDC reference: 2205278
Structure description
Flavanones exhibit a wide range of biological properties, including antiviral (Shi et al., 2022), antifungal (Emami et al. 2013) and anticancer activities (Bailly, 2021; Zhao et al., 2019) as well as being used in the treatment of Alzheimer's disease (Jin et al., 2021). In continuation of our research into flavanone derivatives (Sung, 2020), the title compound was synthesized and its was determined.
The title compound, C21H18O4, was prepared in a two-step reaction. A Claisen–Schmidt condensation reaction between 2,3-dimethoxy-benzaldehyde and 2-hydroxy-1-acetonaphthone gave the corresponding benzochalcone, which was then used for an intramolecular Michael to provide the desired flavanone (Yong et al. 2014). The molecular structure of the title compound is shown in Fig. 1. The central pyran ring (C1/C2/C3/O2/C12/C21) has an with atom C3 as the flap. C3 is a stereogenic centre: in the arbitrarily chosen C3 has an S configuration, but crystal symmetry generates a The hydrogen atom H3 attached to C3 forms a trans diaxial conformation with atom H2B of the C2 methylene group (H3—C3—C2—H2B = −179.1°) and a gauche conformation with the other H atom attached to C2 (H3—C3—C2—H2A = −60.8°). The methoxy group at the meta position of the benzene ring is twisted slightly from the ring [C9—C7—O4—C8 = 9.5 (5)°]. However, the methoxy group at the ortho position is significantly distorted from the benzene ring due to with the pyran ring [C4—C5—O3—C6 = 105.9 (4)°]. The C12–C21 naphthalene ring system (r.m.s. deviation = 0.036 Å) and benzene ring (C4/ C5/C7/ C11/C9/C10]; r.m.s. deviation = 0.003 Å) lie almost perpendicular to each other forming a dihedral angle of 88.31 (1)°. In the crystal, pairs of C18—H18⋯O1 hydrogen bonds form an inversion dimer with graph-set notation R22(14). The dimers are linked by another pair of C13—H13⋯O2 hydrogen bonds to form a [210] chain. (Table 1, Fig. 2).
Synthesis and crystallization
A solution of 2-hydroxy-1-acetonaphthone (186 mg, 1 mmol) and 2,3-dimethoxybenzaldehyde (166 mg, 1 mmol) was dissolved in ethanol (15 ml) and the temperature was adjusted to around 276–277 K in an ice bath. To the cooled reaction mixture was added 1.0 ml of 40% aqueous KOH solution, and the reaction mixture was stirred at room temperature for 24 h. This mixture was poured into iced water (50 ml) acidified with 6 N HCl solution. The mixture was extracted with ethyl acetate (3 × 30 ml) and the combined organic layers were dried under MgSO4. Filtration and evaporation of the filtrate gave a solid chalcone, which was dissolved in DMSO and a catalytic amount of conc. HCl was added. After 10 h, the reaction mixture was poured into iced water to give a solid flavanone. Recrystallization from ethanol solution gave the crystals used in this X-ray diffraction study.
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2Structural data
CCDC reference: 2205278
https://doi.org/10.1107/S2414314622008859/hb4411sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314622008859/hb4411Isup2.hkl
Data collection: APEX2 (Bruker, 2012); cell
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).C21H18O4 | Z = 2 |
Mr = 334.35 | F(000) = 352 |
Triclinic, P1 | Dx = 1.357 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 8.3312 (14) Å | Cell parameters from 2013 reflections |
b = 9.6506 (16) Å | θ = 2.7–25.9° |
c = 11.797 (2) Å | µ = 0.09 mm−1 |
α = 94.261 (4)° | T = 200 K |
β = 107.335 (4)° | Block, yellow |
γ = 112.326 (3)° | 0.34 × 0.21 × 0.16 mm |
V = 818.4 (2) Å3 |
Bruker SMART CCD diffractometer | 3202 independent reflections |
Radiation source: fine-focus sealed tube | 2136 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.020 |
ω scans | θmax = 26.1°, θmin = 2.3° |
Absorption correction: multi-scan (SADABS; Krause et al., 2015) | h = −10→9 |
Tmin = 0.969, Tmax = 0.985 | k = −11→11 |
5181 measured reflections | l = −14→13 |
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)] = 0.057 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.204 | H-atom parameters constrained |
S = 1.13 | w = 1/[σ2(Fo2) + (0.0727P)2 + 0.8943P] where P = (Fo2 + 2Fc2)/3 |
3202 reflections | (Δ/σ)max < 0.001 |
228 parameters | Δρmax = 0.30 e Å−3 |
0 restraints | Δρmin = −0.38 e Å−3 |
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. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.5916 (4) | 0.4265 (4) | 0.1200 (3) | 0.0387 (7) | |
O1 | 0.7393 (3) | 0.5280 (3) | 0.1255 (2) | 0.0534 (7) | |
C2 | 0.4897 (5) | 0.4555 (4) | 0.1987 (3) | 0.0467 (8) | |
H2A | 0.5804 | 0.5215 | 0.2782 | 0.056* | |
H2B | 0.4162 | 0.5101 | 0.1594 | 0.056* | |
C3 | 0.3641 (4) | 0.3088 (4) | 0.2179 (3) | 0.0404 (8) | |
H3 | 0.4419 | 0.2569 | 0.2588 | 0.048* | |
O2 | 0.2359 (3) | 0.2101 (2) | 0.10246 (19) | 0.0406 (6) | |
C4 | 0.2501 (4) | 0.3214 (4) | 0.2935 (3) | 0.0387 (7) | |
C5 | 0.2559 (4) | 0.2556 (3) | 0.3936 (3) | 0.0368 (7) | |
O3 | 0.3634 (3) | 0.1743 (3) | 0.4229 (2) | 0.0470 (6) | |
C6 | 0.5292 (5) | 0.2525 (5) | 0.5253 (4) | 0.0649 (11) | |
H6A | 0.6015 | 0.3530 | 0.5121 | 0.097* | |
H6B | 0.6025 | 0.1923 | 0.5364 | 0.097* | |
H6C | 0.4983 | 0.2664 | 0.5979 | 0.097* | |
C7 | 0.1468 (4) | 0.2610 (4) | 0.4626 (3) | 0.0396 (7) | |
O4 | 0.1617 (3) | 0.1893 (3) | 0.5578 (2) | 0.0501 (6) | |
C8 | 0.0315 (5) | 0.1696 (5) | 0.6180 (4) | 0.0558 (10) | |
H8A | 0.0463 | 0.2702 | 0.6546 | 0.084* | |
H8B | 0.0537 | 0.1122 | 0.6816 | 0.084* | |
H8C | −0.0947 | 0.1128 | 0.5590 | 0.084* | |
C9 | 0.0321 (5) | 0.3356 (4) | 0.4296 (3) | 0.0443 (8) | |
H9 | −0.0429 | 0.3403 | 0.4753 | 0.053* | |
C10 | 0.0275 (5) | 0.4029 (4) | 0.3300 (3) | 0.0474 (8) | |
H10 | −0.0501 | 0.4549 | 0.3083 | 0.057* | |
C11 | 0.1337 (5) | 0.3958 (4) | 0.2616 (3) | 0.0452 (8) | |
H11 | 0.1277 | 0.4416 | 0.1928 | 0.054* | |
C12 | 0.3185 (4) | 0.1820 (4) | 0.0248 (3) | 0.0366 (7) | |
C13 | 0.2063 (4) | 0.0489 (4) | −0.0672 (3) | 0.0425 (8) | |
H13 | 0.0818 | −0.0104 | −0.0740 | 0.051* | |
C14 | 0.2764 (5) | 0.0057 (4) | −0.1459 (3) | 0.0427 (8) | |
H14 | 0.1997 | −0.0838 | −0.2083 | 0.051* | |
C15 | 0.4630 (4) | 0.0918 (4) | −0.1370 (3) | 0.0378 (7) | |
C16 | 0.5352 (5) | 0.0391 (4) | −0.2161 (3) | 0.0428 (8) | |
H16 | 0.4571 | −0.0510 | −0.2778 | 0.051* | |
C17 | 0.7169 (5) | 0.1166 (4) | −0.2048 (3) | 0.0482 (9) | |
H17 | 0.7653 | 0.0800 | −0.2577 | 0.058* | |
C18 | 0.8306 (5) | 0.2500 (4) | −0.1150 (3) | 0.0474 (9) | |
H18 | 0.9572 | 0.3027 | −0.1065 | 0.057* | |
C19 | 0.7633 (5) | 0.3060 (4) | −0.0389 (3) | 0.0438 (8) | |
H19 | 0.8427 | 0.3985 | 0.0200 | 0.053* | |
C20 | 0.5757 (4) | 0.2274 (4) | −0.0469 (3) | 0.0366 (7) | |
C21 | 0.4989 (4) | 0.2770 (3) | 0.0347 (3) | 0.0364 (7) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0354 (17) | 0.0354 (16) | 0.0444 (18) | 0.0114 (14) | 0.0171 (14) | 0.0101 (14) |
O1 | 0.0415 (14) | 0.0415 (13) | 0.0690 (17) | 0.0044 (11) | 0.0286 (13) | 0.0005 (12) |
C2 | 0.0425 (19) | 0.0418 (18) | 0.053 (2) | 0.0108 (15) | 0.0244 (16) | −0.0009 (16) |
C3 | 0.0327 (16) | 0.0440 (18) | 0.0390 (17) | 0.0112 (14) | 0.0130 (14) | 0.0041 (14) |
O2 | 0.0309 (11) | 0.0458 (12) | 0.0404 (12) | 0.0101 (10) | 0.0165 (10) | 0.0001 (10) |
C4 | 0.0335 (16) | 0.0407 (17) | 0.0353 (17) | 0.0101 (14) | 0.0120 (14) | 0.0028 (14) |
C5 | 0.0330 (16) | 0.0334 (16) | 0.0428 (18) | 0.0123 (13) | 0.0157 (14) | 0.0027 (14) |
O3 | 0.0464 (14) | 0.0478 (13) | 0.0530 (14) | 0.0236 (11) | 0.0217 (12) | 0.0090 (11) |
C6 | 0.048 (2) | 0.087 (3) | 0.055 (2) | 0.034 (2) | 0.0076 (19) | 0.006 (2) |
C7 | 0.0399 (18) | 0.0389 (17) | 0.0393 (17) | 0.0124 (15) | 0.0198 (15) | 0.0042 (14) |
O4 | 0.0556 (15) | 0.0598 (15) | 0.0489 (14) | 0.0277 (13) | 0.0312 (12) | 0.0186 (12) |
C8 | 0.061 (2) | 0.061 (2) | 0.056 (2) | 0.023 (2) | 0.039 (2) | 0.0157 (19) |
C9 | 0.0443 (19) | 0.0452 (18) | 0.0471 (19) | 0.0172 (16) | 0.0246 (16) | 0.0045 (15) |
C10 | 0.0438 (19) | 0.050 (2) | 0.053 (2) | 0.0234 (17) | 0.0196 (17) | 0.0080 (17) |
C11 | 0.0451 (19) | 0.0470 (19) | 0.0431 (19) | 0.0180 (16) | 0.0163 (16) | 0.0131 (15) |
C12 | 0.0325 (16) | 0.0436 (17) | 0.0360 (17) | 0.0157 (14) | 0.0158 (14) | 0.0080 (14) |
C13 | 0.0292 (16) | 0.0429 (18) | 0.0457 (19) | 0.0065 (14) | 0.0136 (14) | 0.0007 (15) |
C14 | 0.0402 (18) | 0.0417 (18) | 0.0411 (18) | 0.0120 (15) | 0.0161 (15) | 0.0013 (14) |
C15 | 0.0361 (17) | 0.0385 (17) | 0.0371 (17) | 0.0141 (14) | 0.0127 (14) | 0.0084 (14) |
C16 | 0.0433 (19) | 0.0439 (18) | 0.0452 (19) | 0.0190 (15) | 0.0208 (16) | 0.0074 (15) |
C17 | 0.054 (2) | 0.050 (2) | 0.053 (2) | 0.0255 (18) | 0.0306 (18) | 0.0131 (17) |
C18 | 0.0397 (18) | 0.050 (2) | 0.061 (2) | 0.0178 (16) | 0.0294 (17) | 0.0189 (17) |
C19 | 0.0370 (18) | 0.0438 (18) | 0.051 (2) | 0.0136 (15) | 0.0213 (16) | 0.0105 (15) |
C20 | 0.0343 (16) | 0.0380 (16) | 0.0404 (17) | 0.0147 (14) | 0.0165 (14) | 0.0135 (14) |
C21 | 0.0315 (16) | 0.0371 (16) | 0.0396 (17) | 0.0120 (13) | 0.0143 (14) | 0.0080 (14) |
C1—O1 | 1.227 (4) | C8—H8C | 0.9800 |
C1—C21 | 1.471 (4) | C9—C10 | 1.381 (5) |
C1—C2 | 1.507 (4) | C9—H9 | 0.9500 |
C2—C3 | 1.488 (5) | C10—C11 | 1.379 (5) |
C2—H2A | 0.9900 | C10—H10 | 0.9500 |
C2—H2B | 0.9900 | C11—H11 | 0.9500 |
C3—O2 | 1.439 (4) | C12—C21 | 1.394 (4) |
C3—C4 | 1.513 (4) | C12—C13 | 1.406 (4) |
C3—H3 | 1.0000 | C13—C14 | 1.352 (4) |
O2—C12 | 1.366 (3) | C13—H13 | 0.9500 |
C4—C5 | 1.379 (4) | C14—C15 | 1.423 (4) |
C4—C11 | 1.396 (5) | C14—H14 | 0.9500 |
C5—O3 | 1.389 (4) | C15—C20 | 1.410 (4) |
C5—C7 | 1.400 (4) | C15—C16 | 1.410 (4) |
O3—C6 | 1.419 (4) | C16—C17 | 1.369 (5) |
C6—H6A | 0.9800 | C16—H16 | 0.9500 |
C6—H6B | 0.9800 | C17—C18 | 1.396 (5) |
C6—H6C | 0.9800 | C17—H17 | 0.9500 |
C7—O4 | 1.362 (4) | C18—C19 | 1.367 (5) |
C7—C9 | 1.388 (5) | C18—H18 | 0.9500 |
O4—C8 | 1.428 (4) | C19—C20 | 1.424 (4) |
C8—H8A | 0.9800 | C19—H19 | 0.9500 |
C8—H8B | 0.9800 | C20—C21 | 1.449 (4) |
O1—C1—C21 | 123.8 (3) | C10—C9—C7 | 119.7 (3) |
O1—C1—C2 | 119.8 (3) | C10—C9—H9 | 120.1 |
C21—C1—C2 | 116.4 (3) | C7—C9—H9 | 120.1 |
C3—C2—C1 | 110.8 (3) | C11—C10—C9 | 121.1 (3) |
C3—C2—H2A | 109.5 | C11—C10—H10 | 119.5 |
C1—C2—H2A | 109.5 | C9—C10—H10 | 119.5 |
C3—C2—H2B | 109.5 | C10—C11—C4 | 120.0 (3) |
C1—C2—H2B | 109.5 | C10—C11—H11 | 120.0 |
H2A—C2—H2B | 108.1 | C4—C11—H11 | 120.0 |
O2—C3—C2 | 109.8 (3) | O2—C12—C21 | 123.3 (3) |
O2—C3—C4 | 107.0 (2) | O2—C12—C13 | 114.5 (3) |
C2—C3—C4 | 116.2 (3) | C21—C12—C13 | 122.3 (3) |
O2—C3—H3 | 107.8 | C14—C13—C12 | 119.7 (3) |
C2—C3—H3 | 107.8 | C14—C13—H13 | 120.2 |
C4—C3—H3 | 107.8 | C12—C13—H13 | 120.2 |
C12—O2—C3 | 114.2 (2) | C13—C14—C15 | 121.3 (3) |
C5—C4—C11 | 118.8 (3) | C13—C14—H14 | 119.4 |
C5—C4—C3 | 120.3 (3) | C15—C14—H14 | 119.4 |
C11—C4—C3 | 120.9 (3) | C20—C15—C16 | 120.5 (3) |
C4—C5—O3 | 119.6 (3) | C20—C15—C14 | 119.6 (3) |
C4—C5—C7 | 121.4 (3) | C16—C15—C14 | 119.9 (3) |
O3—C5—C7 | 118.9 (3) | C17—C16—C15 | 120.6 (3) |
C5—O3—C6 | 114.0 (3) | C17—C16—H16 | 119.7 |
O3—C6—H6A | 109.5 | C15—C16—H16 | 119.7 |
O3—C6—H6B | 109.5 | C16—C17—C18 | 119.5 (3) |
H6A—C6—H6B | 109.5 | C16—C17—H17 | 120.2 |
O3—C6—H6C | 109.5 | C18—C17—H17 | 120.2 |
H6A—C6—H6C | 109.5 | C19—C18—C17 | 121.2 (3) |
H6B—C6—H6C | 109.5 | C19—C18—H18 | 119.4 |
O4—C7—C9 | 125.0 (3) | C17—C18—H18 | 119.4 |
O4—C7—C5 | 116.0 (3) | C18—C19—C20 | 120.8 (3) |
C9—C7—C5 | 119.0 (3) | C18—C19—H19 | 119.6 |
C7—O4—C8 | 117.8 (3) | C20—C19—H19 | 119.6 |
O4—C8—H8A | 109.5 | C15—C20—C19 | 117.4 (3) |
O4—C8—H8B | 109.5 | C15—C20—C21 | 119.2 (3) |
H8A—C8—H8B | 109.5 | C19—C20—C21 | 123.4 (3) |
O4—C8—H8C | 109.5 | C12—C21—C20 | 117.7 (3) |
H8A—C8—H8C | 109.5 | C12—C21—C1 | 117.6 (3) |
H8B—C8—H8C | 109.5 | C20—C21—C1 | 124.5 (3) |
O1—C1—C2—C3 | −156.5 (3) | C3—O2—C12—C13 | 158.7 (3) |
C21—C1—C2—C3 | 26.8 (4) | O2—C12—C13—C14 | −176.9 (3) |
C1—C2—C3—O2 | −57.2 (4) | C21—C12—C13—C14 | 3.3 (5) |
C1—C2—C3—C4 | −178.8 (3) | C12—C13—C14—C15 | 0.6 (5) |
C2—C3—O2—C12 | 55.5 (3) | C13—C14—C15—C20 | −2.0 (5) |
C4—C3—O2—C12 | −177.5 (3) | C13—C14—C15—C16 | 176.4 (3) |
O2—C3—C4—C5 | 111.0 (3) | C20—C15—C16—C17 | 1.6 (5) |
C2—C3—C4—C5 | −125.9 (3) | C14—C15—C16—C17 | −176.8 (3) |
O2—C3—C4—C11 | −67.2 (4) | C15—C16—C17—C18 | −0.8 (5) |
C2—C3—C4—C11 | 55.9 (4) | C16—C17—C18—C19 | −0.9 (5) |
C11—C4—C5—O3 | 176.6 (3) | C17—C18—C19—C20 | 1.7 (5) |
C3—C4—C5—O3 | −1.6 (4) | C16—C15—C20—C19 | −0.8 (5) |
C11—C4—C5—C7 | 0.5 (5) | C14—C15—C20—C19 | 177.6 (3) |
C3—C4—C5—C7 | −177.7 (3) | C16—C15—C20—C21 | −178.7 (3) |
C4—C5—O3—C6 | 105.9 (4) | C14—C15—C20—C21 | −0.3 (5) |
C7—C5—O3—C6 | −77.9 (4) | C18—C19—C20—C15 | −0.9 (5) |
C4—C5—C7—O4 | 178.7 (3) | C18—C19—C20—C21 | 177.0 (3) |
O3—C5—C7—O4 | 2.6 (4) | O2—C12—C21—C20 | 174.8 (3) |
C4—C5—C7—C9 | −0.6 (5) | C13—C12—C21—C20 | −5.5 (5) |
O3—C5—C7—C9 | −176.7 (3) | O2—C12—C21—C1 | −10.3 (5) |
C9—C7—O4—C8 | 9.5 (5) | C13—C12—C21—C1 | 169.4 (3) |
C5—C7—O4—C8 | −169.8 (3) | C15—C20—C21—C12 | 3.9 (4) |
O4—C7—C9—C10 | −179.3 (3) | C19—C20—C21—C12 | −173.9 (3) |
C5—C7—C9—C10 | 0.0 (5) | C15—C20—C21—C1 | −170.6 (3) |
C7—C9—C10—C11 | 0.7 (5) | C19—C20—C21—C1 | 11.6 (5) |
C9—C10—C11—C4 | −0.8 (5) | O1—C1—C21—C12 | −170.1 (3) |
C5—C4—C11—C10 | 0.2 (5) | C2—C1—C21—C12 | 6.4 (4) |
C3—C4—C11—C10 | 178.4 (3) | O1—C1—C21—C20 | 4.4 (5) |
C3—O2—C12—C21 | −21.5 (4) | C2—C1—C21—C20 | −179.1 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
C13—H13···O2i | 0.95 | 2.52 | 3.454 (4) | 169 |
C18—H18···O1ii | 0.95 | 2.52 | 3.452 (4) | 166 |
Symmetry codes: (i) −x, −y, −z; (ii) −x+2, −y+1, −z. |
Funding information
This work was supported by a Dongduk Women's University grant.
References
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