organic compounds
2-(4-Hydroxyphenyl)-3-methoxy-4H-chromen-4-one
aInstitute of Chemistry, V.N. Karazin National University, Svobody 4, 61077 Kharkiv, Ukraine, and bFaculty of Chemistry, University of Gdańsk, J. Sobieskiego 18, 80-952 Gdańsk, Poland
*Correspondence e-mail: bla@chem.univ.gda.pl
In the title compound, C16H12O4, the substituent benzene ring and methoxy group are twisted relative to the 4H-chromene skeleton by 24.1 (1) and 61.3 (1)°, respectively. In the crystal, molecules are connected by classical O—H⋯O and weak C—H⋯O hydrogen bonds, forming chains parallel to [201]. The 4H-chromene ring systems of adjacent molecules are either parallel or inclined at an angle of 28.9 (1)°.
Related literature
For general features of flavones and flavonols (derivatives of 3-hydroxy-2-phenyl-4H-chromen-4-one), see: Demchenko (2009); Ma et al. (2012). For related structures, see: Wera et al. (2011a,b). For intermolecular interactions, see: Aakeröy et al. (1992); Etter et al. (1990); Novoa et al. (2006). For the synthesis, see: Bader et al. (2003); Wera et al. (2011b).
Experimental
Crystal data
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Data collection: CrysAlis CCD (Oxford Diffraction, 2008); cell CrysAlis CCD; data reduction: CrysAlis RED (Oxford Diffraction, 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 and PLATON (Spek, 2009).
Supporting information
10.1107/S1600536813010982/xu5696sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536813010982/xu5696Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536813010982/xu5696Isup3.cml
The title compound was synthesized in four steps. First, 1-(2-hydroxyphenyl)-3-{4-[(4-methoxybenzyl)oxy]phenyl}prop-2-en-1-one (chalcone) was prepared by the condensation (with the elimination of water) of 1-(2-hydroxyphenyl)ethanone with 4-[(4-methoxybenzyl)oxy]benzaldehyde in N-methylpyrrolidone/aqueous KOH (1/1 v/v), then precipitated by neutralizing the reaction mixture with aqueous HCl and recrystallized from methanol. Next, chalcone was oxidatively cyclized in a K2CO3/methanol/H2O2 mixture, yielding to 3-hydroxy-2-{4-[(4-methoxybenzyl)oxy]phenyl}-4H-chromen-4-one (Bader et al., 2003; Wera et al., 2011b). This product was then alkylated by dimethyl sulfate in an acetonitrile/K2CO3 mixture. Finally, the 3-methoxy-2-{4-[(4-methoxybenzyl)oxy]phenyl}-4H-chromen-4-one thus obtained was heated in acetic acid to give the title compound [2-(4-hydroxyphenyl)-3-methoxy-4H-chromen-4-one] with a yield of 34%. Pale yellow crystals suitable for X-ray investigations were grown from 1,4-dioxane solutions of the chromatographically purified (Silica Gel, 2-propanol/chloroform, 1/20 v/v) precipitate of the final product (m.p. = 506–507 K).
H atoms of C–H bonds were positioned geometrically, with C–H = 0.93 Å and 0.96 Å for the aromatic and methyl H atoms, respectively, and constrained to ride on their parent atoms with Uiso(H) = xUeq(C) where x = 1.2 for the aromatic H and 1.5 for methyl H atoms. Hydroxy H atom was located on a difference Fourier map and refined isotropically with Uiso(H) = 1.5Ueq(O).
Data collection: CrysAlis CCD (Oxford Diffraction, 2008); cell
CrysAlis CCD (Oxford Diffraction, 2008); data reduction: CrysAlis RED (Oxford Diffraction, 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).C16H12O4 | F(000) = 560 |
Mr = 268.26 | Dx = 1.416 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.7107 Å |
Hall symbol: -P 2ybc | Cell parameters from 2245 reflections |
a = 8.7191 (5) Å | θ = 3.3–25.1° |
b = 8.8978 (4) Å | µ = 0.10 mm−1 |
c = 16.706 (1) Å | T = 295 K |
β = 103.801 (6)° | Prism, pale yellow |
V = 1258.65 (12) Å3 | 0.6 × 0.45 × 0.25 mm |
Z = 4 |
Oxford Diffraction Gemini R Ultra Ruby CCD diffractometer | 2245 independent reflections |
Radiation source: Enhance (Mo) X-ray Source | 1801 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.021 |
Detector resolution: 10.4002 pixels mm-1 | θmax = 25.1°, θmin = 3.3° |
ω scans | h = −7→10 |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2008) | k = −10→10 |
Tmin = 0.943, Tmax = 0.970 | l = −18→19 |
5100 measured reflections |
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)] = 0.040 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.107 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0515P)2 + 0.1866P] where P = (Fo2 + 2Fc2)/3 |
2245 reflections | (Δ/σ)max < 0.001 |
185 parameters | Δρmax = 0.14 e Å−3 |
0 restraints | Δρmin = −0.18 e Å−3 |
C16H12O4 | V = 1258.65 (12) Å3 |
Mr = 268.26 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 8.7191 (5) Å | µ = 0.10 mm−1 |
b = 8.8978 (4) Å | T = 295 K |
c = 16.706 (1) Å | 0.6 × 0.45 × 0.25 mm |
β = 103.801 (6)° |
Oxford Diffraction Gemini R Ultra Ruby CCD diffractometer | 2245 independent reflections |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2008) | 1801 reflections with I > 2σ(I) |
Tmin = 0.943, Tmax = 0.970 | Rint = 0.021 |
5100 measured reflections |
R[F2 > 2σ(F2)] = 0.040 | 0 restraints |
wR(F2) = 0.107 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 0.14 e Å−3 |
2245 reflections | Δρmin = −0.18 e Å−3 |
185 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s 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. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.26225 (13) | 0.08174 (12) | 0.03249 (6) | 0.0445 (3) | |
C2 | 0.31549 (18) | −0.06240 (17) | 0.03302 (10) | 0.0390 (4) | |
C3 | 0.2506 (2) | −0.15818 (18) | −0.02953 (10) | 0.0443 (4) | |
C4 | 0.1209 (2) | −0.1136 (2) | −0.09642 (10) | 0.0503 (5) | |
C5 | −0.0405 (2) | 0.1077 (3) | −0.16006 (12) | 0.0656 (6) | |
H5 | −0.0915 | 0.0491 | −0.2046 | 0.079* | |
C6 | −0.0777 (3) | 0.2560 (3) | −0.15735 (13) | 0.0762 (7) | |
H6 | −0.1540 | 0.2979 | −0.2001 | 0.091* | |
C7 | −0.0028 (3) | 0.3448 (3) | −0.09160 (13) | 0.0729 (6) | |
H7 | −0.0295 | 0.4459 | −0.0906 | 0.087* | |
C8 | 0.1101 (2) | 0.2854 (2) | −0.02795 (11) | 0.0589 (5) | |
H8 | 0.1607 | 0.3449 | 0.0163 | 0.071* | |
C9 | 0.07400 (19) | 0.0433 (2) | −0.09613 (10) | 0.0488 (5) | |
C10 | 0.14684 (19) | 0.1346 (2) | −0.03126 (10) | 0.0451 (4) | |
O11 | 0.29961 (17) | −0.30466 (13) | −0.02436 (8) | 0.0603 (4) | |
O12 | 0.05411 (16) | −0.20337 (16) | −0.15021 (8) | 0.0712 (4) | |
C13 | 0.43909 (17) | −0.09082 (16) | 0.10765 (9) | 0.0358 (4) | |
C14 | 0.4500 (2) | 0.00252 (18) | 0.17590 (10) | 0.0460 (4) | |
H14 | 0.3772 | 0.0799 | 0.1733 | 0.055* | |
C15 | 0.5654 (2) | −0.01740 (19) | 0.24656 (10) | 0.0483 (4) | |
H15 | 0.5694 | 0.0456 | 0.2914 | 0.058* | |
C16 | 0.67592 (19) | −0.12985 (17) | 0.25180 (10) | 0.0403 (4) | |
C17 | 0.66761 (19) | −0.22373 (17) | 0.18547 (10) | 0.0417 (4) | |
H17 | 0.7414 | −0.3003 | 0.1885 | 0.050* | |
C18 | 0.55044 (19) | −0.20481 (16) | 0.11453 (10) | 0.0406 (4) | |
H18 | 0.5458 | −0.2697 | 0.0704 | 0.049* | |
C19 | 0.3675 (3) | −0.3531 (2) | −0.09013 (14) | 0.0818 (7) | |
H19A | 0.2869 | −0.3571 | −0.1405 | 0.123* | |
H19B | 0.4130 | −0.4511 | −0.0778 | 0.123* | |
H19C | 0.4481 | −0.2835 | −0.0962 | 0.123* | |
O20 | 0.78716 (16) | −0.14223 (15) | 0.32342 (8) | 0.0600 (4) | |
H20 | 0.867 (3) | −0.209 (3) | 0.3198 (15) | 0.090* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0465 (7) | 0.0475 (7) | 0.0342 (6) | 0.0080 (5) | −0.0007 (5) | −0.0006 (5) |
C2 | 0.0394 (9) | 0.0405 (9) | 0.0364 (9) | −0.0031 (7) | 0.0078 (7) | −0.0004 (7) |
C3 | 0.0477 (10) | 0.0457 (9) | 0.0382 (10) | −0.0106 (8) | 0.0074 (8) | −0.0029 (7) |
C4 | 0.0425 (10) | 0.0709 (12) | 0.0363 (10) | −0.0205 (9) | 0.0075 (8) | −0.0040 (8) |
C5 | 0.0418 (10) | 0.1093 (18) | 0.0412 (11) | −0.0004 (11) | 0.0011 (9) | 0.0086 (11) |
C6 | 0.0557 (13) | 0.123 (2) | 0.0467 (13) | 0.0313 (13) | 0.0047 (10) | 0.0234 (13) |
C7 | 0.0751 (14) | 0.0945 (16) | 0.0489 (13) | 0.0405 (13) | 0.0144 (11) | 0.0157 (11) |
C8 | 0.0638 (12) | 0.0716 (13) | 0.0405 (11) | 0.0243 (10) | 0.0109 (9) | 0.0053 (9) |
C9 | 0.0357 (9) | 0.0756 (12) | 0.0339 (9) | −0.0045 (8) | 0.0062 (7) | 0.0050 (8) |
C10 | 0.0365 (9) | 0.0655 (11) | 0.0325 (9) | 0.0077 (8) | 0.0069 (7) | 0.0073 (8) |
O11 | 0.0815 (10) | 0.0453 (7) | 0.0497 (8) | −0.0114 (6) | 0.0069 (7) | −0.0083 (6) |
O12 | 0.0654 (9) | 0.0919 (10) | 0.0484 (8) | −0.0313 (8) | −0.0021 (7) | −0.0173 (7) |
C13 | 0.0363 (8) | 0.0346 (8) | 0.0356 (9) | −0.0031 (7) | 0.0068 (7) | −0.0008 (6) |
C14 | 0.0451 (9) | 0.0458 (9) | 0.0427 (10) | 0.0103 (8) | 0.0018 (8) | −0.0065 (7) |
C15 | 0.0497 (10) | 0.0511 (10) | 0.0389 (10) | 0.0079 (8) | −0.0001 (8) | −0.0113 (8) |
C16 | 0.0391 (9) | 0.0412 (8) | 0.0371 (9) | −0.0008 (7) | 0.0020 (7) | 0.0038 (7) |
C17 | 0.0413 (9) | 0.0362 (8) | 0.0471 (10) | 0.0060 (7) | 0.0092 (8) | 0.0029 (7) |
C18 | 0.0458 (10) | 0.0370 (8) | 0.0387 (9) | −0.0021 (7) | 0.0097 (8) | −0.0056 (7) |
C19 | 0.1109 (19) | 0.0646 (13) | 0.0691 (15) | 0.0072 (13) | 0.0199 (14) | −0.0224 (11) |
O20 | 0.0549 (8) | 0.0682 (9) | 0.0459 (8) | 0.0154 (6) | −0.0100 (6) | −0.0035 (6) |
O1—C10 | 1.3627 (18) | C9—C10 | 1.382 (2) |
O1—C2 | 1.3633 (19) | O11—C19 | 1.433 (3) |
C2—C3 | 1.362 (2) | C13—C18 | 1.390 (2) |
C2—C13 | 1.462 (2) | C13—C14 | 1.395 (2) |
C3—O11 | 1.368 (2) | C14—C15 | 1.368 (2) |
C3—C4 | 1.443 (2) | C14—H14 | 0.9300 |
C4—O12 | 1.239 (2) | C15—C16 | 1.377 (2) |
C4—C9 | 1.455 (3) | C15—H15 | 0.9300 |
C5—C6 | 1.362 (3) | C16—O20 | 1.3530 (19) |
C5—C9 | 1.399 (2) | C16—C17 | 1.376 (2) |
C5—H5 | 0.9300 | C17—C18 | 1.378 (2) |
C6—C7 | 1.384 (3) | C17—H17 | 0.9300 |
C6—H6 | 0.9300 | C18—H18 | 0.9300 |
C7—C8 | 1.371 (3) | C19—H19A | 0.9600 |
C7—H7 | 0.9300 | C19—H19B | 0.9600 |
C8—C10 | 1.383 (3) | C19—H19C | 0.9600 |
C8—H8 | 0.9300 | O20—H20 | 0.93 (3) |
C10—O1—C2 | 121.13 (13) | C9—C10—C8 | 122.28 (16) |
C3—C2—O1 | 120.33 (14) | C3—O11—C19 | 114.71 (15) |
C3—C2—C13 | 129.24 (15) | C18—C13—C14 | 117.18 (14) |
O1—C2—C13 | 110.41 (12) | C18—C13—C2 | 123.70 (14) |
C2—C3—O11 | 118.76 (15) | C14—C13—C2 | 119.10 (14) |
C2—C3—C4 | 121.84 (16) | C15—C14—C13 | 121.37 (15) |
O11—C3—C4 | 119.09 (14) | C15—C14—H14 | 119.3 |
O12—C4—C3 | 122.05 (18) | C13—C14—H14 | 119.3 |
O12—C4—C9 | 122.48 (17) | C14—C15—C16 | 120.58 (15) |
C3—C4—C9 | 115.47 (15) | C14—C15—H15 | 119.7 |
C6—C5—C9 | 120.2 (2) | C16—C15—H15 | 119.7 |
C6—C5—H5 | 119.9 | O20—C16—C17 | 123.49 (15) |
C9—C5—H5 | 119.9 | O20—C16—C15 | 117.29 (15) |
C5—C6—C7 | 120.58 (19) | C17—C16—C15 | 119.22 (15) |
C5—C6—H6 | 119.7 | C16—C17—C18 | 120.29 (14) |
C7—C6—H6 | 119.7 | C16—C17—H17 | 119.9 |
C8—C7—C6 | 120.7 (2) | C18—C17—H17 | 119.9 |
C8—C7—H7 | 119.6 | C17—C18—C13 | 121.35 (14) |
C6—C7—H7 | 119.6 | C17—C18—H18 | 119.3 |
C7—C8—C10 | 118.22 (19) | C13—C18—H18 | 119.3 |
C7—C8—H8 | 120.9 | O11—C19—H19A | 109.5 |
C10—C8—H8 | 120.9 | O11—C19—H19B | 109.5 |
C10—C9—C5 | 117.95 (18) | H19A—C19—H19B | 109.5 |
C10—C9—C4 | 119.33 (15) | O11—C19—H19C | 109.5 |
C5—C9—C4 | 122.71 (17) | H19A—C19—H19C | 109.5 |
O1—C10—C9 | 121.69 (16) | H19B—C19—H19C | 109.5 |
O1—C10—C8 | 116.01 (15) | C16—O20—H20 | 112.6 (15) |
C10—O1—C2—C3 | −1.9 (2) | C4—C9—C10—O1 | 0.3 (2) |
C10—O1—C2—C13 | 179.79 (13) | C5—C9—C10—C8 | 0.0 (3) |
O1—C2—C3—O11 | −175.76 (14) | C4—C9—C10—C8 | 178.69 (17) |
C13—C2—C3—O11 | 2.2 (3) | C7—C8—C10—O1 | 178.60 (17) |
O1—C2—C3—C4 | −2.3 (2) | C7—C8—C10—C9 | 0.1 (3) |
C13—C2—C3—C4 | 175.66 (15) | C2—C3—O11—C19 | −120.39 (19) |
C2—C3—C4—O12 | −174.71 (16) | C4—C3—O11—C19 | 65.9 (2) |
O11—C3—C4—O12 | −1.2 (3) | C3—C2—C13—C18 | 23.8 (3) |
C2—C3—C4—C9 | 5.1 (2) | O1—C2—C13—C18 | −158.16 (14) |
O11—C3—C4—C9 | 178.60 (15) | C3—C2—C13—C14 | −157.69 (17) |
C9—C5—C6—C7 | 0.1 (3) | O1—C2—C13—C14 | 20.4 (2) |
C5—C6—C7—C8 | 0.0 (3) | C18—C13—C14—C15 | 0.0 (2) |
C6—C7—C8—C10 | −0.1 (3) | C2—C13—C14—C15 | −178.62 (15) |
C6—C5—C9—C10 | −0.1 (3) | C13—C14—C15—C16 | 0.8 (3) |
C6—C5—C9—C4 | −178.73 (19) | C14—C15—C16—O20 | 179.61 (16) |
O12—C4—C9—C10 | 175.76 (16) | C14—C15—C16—C17 | −0.9 (3) |
C3—C4—C9—C10 | −4.1 (2) | O20—C16—C17—C18 | 179.71 (15) |
O12—C4—C9—C5 | −5.6 (3) | C15—C16—C17—C18 | 0.3 (2) |
C3—C4—C9—C5 | 174.56 (16) | C16—C17—C18—C13 | 0.5 (2) |
C2—O1—C10—C9 | 2.9 (2) | C14—C13—C18—C17 | −0.7 (2) |
C2—O1—C10—C8 | −175.60 (15) | C2—C13—C18—C17 | 177.91 (14) |
C5—C9—C10—O1 | −178.42 (15) |
D—H···A | D—H | H···A | D···A | D—H···A |
O20—H20···O12i | 0.93 (3) | 1.77 (3) | 2.648 (2) | 157 (2) |
C7—H7···O20ii | 0.93 | 2.56 | 3.337 (3) | 141 |
Symmetry codes: (i) x+1, −y−1/2, z+1/2; (ii) x−1, −y+1/2, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | C16H12O4 |
Mr | 268.26 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 295 |
a, b, c (Å) | 8.7191 (5), 8.8978 (4), 16.706 (1) |
β (°) | 103.801 (6) |
V (Å3) | 1258.65 (12) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.6 × 0.45 × 0.25 |
Data collection | |
Diffractometer | Oxford Diffraction Gemini R Ultra Ruby CCD diffractometer |
Absorption correction | Multi-scan (CrysAlis RED; Oxford Diffraction, 2008) |
Tmin, Tmax | 0.943, 0.970 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 5100, 2245, 1801 |
Rint | 0.021 |
(sin θ/λ)max (Å−1) | 0.597 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.040, 0.107, 1.03 |
No. of reflections | 2245 |
No. of parameters | 185 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.14, −0.18 |
Computer programs: CrysAlis CCD (Oxford Diffraction, 2008), CrysAlis RED (Oxford Diffraction, 2008), SHELXS97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
O20—H20···O12i | 0.93 (3) | 1.77 (3) | 2.648 (2) | 157 (2) |
C7—H7···O20ii | 0.93 | 2.56 | 3.337 (3) | 141 |
Symmetry codes: (i) x+1, −y−1/2, z+1/2; (ii) x−1, −y+1/2, z−1/2. |
Acknowledgements
This study was financed by the State Funds for Scientific Research (grant DS/530–8220–D184–3).
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Wera, M., Serdiuk, I. E., Roshal, A. D. & Błażejowski, J. (2011b). Acta Cryst. E67, o440. Web of Science CSD CrossRef IUCr Journals Google Scholar
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Flavones (derivatives of 2-phenyl-4H-chromen-4-one) occur in numerous natural systems and have been thoroughly investigated because of their biological relevance (Ma et al., 2012). Related to flavones, 3-hydroxy-2-phenyl-4H-chromen-4-ones (flavonols) exhibit dual fluorescence in condensed phases due to Excited State Intramolecular Proton Transfer (ESIPT) which makes the compounds interesting fluorescent sensors for analytical applications (Demchenko, 2009). Here we present the crystal structure of the flavonol derivative – 2-(4-hydroxyphenyl)-3-methoxy-4H-chromen-4-one – in which ESIPT does not occur. This makes the compound a convenient reference substance in investigations of emission phenomena in this group of compounds.
In the title compound (Fig.1), the bond lengths and angles characterizing the geometry of the 4H-chromen-4-one moiety are similar to those of other compounds of this group (Wera et al., 2011a,b). With respective average deviations from planarity of 0.0309 (1) Å and 0.0037 (1) Å, the 4H-chromen-4-one and benzene ring systems are oriented at a dihedral angle of 24.1 (1)° [in the case of 3-hydroxy-2-(4-hydroxyphenyl)-4H-chromen-4-one this angle is 20.7 (1)° (Wera et al., 2011a), and in 3-hydroxy-2-(4-methoxyphenyl)-4H-chromen-4-one it is 12.3 (1)° (Wera et al., 2011b)]. The methoxy group is twisted relative to the 4H-chromen-4-one ring system through an angle of 61.3 (1)°.
In the crystal structure, molecules connected by a network of O–H···O (Aakeröy et al., 1992), the C(10) motif (Etter et al., 1990) and C–H···O (Novoa et al., 2006) interactions (Table 1, Figs. 2 and 3), are arranged in layers (Fig. 2) that are dispersively stabilized in the crystal lattice (Fig. 3). The 4H-chromene cores are either parallel or oriented at an angle of 28.9 (1)°, while the benzene rings are parallel or inclined at an angle of 76.6 (1)°.