Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807018697/sj2294sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807018697/sj2294Isup2.hkl |
CCDC reference: 647597
Key indicators
- Single-crystal X-ray study
- T = 100 K
- Mean (C-C) = 0.001 Å
- R factor = 0.049
- wR factor = 0.157
- Data-to-parameter ratio = 31.7
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT153_ALERT_1_C The su's on the Cell Axes are Equal (x 100000) . 20 Ang. PLAT154_ALERT_1_C The su's on the Cell Angles are Equal (x 10000) 100 Deg. PLAT180_ALERT_3_C Check Cell Rounding: # of Values Ending with 0 = 3
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 3 ALERT level C = Check and explain 0 ALERT level G = General alerts; check 2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 0 ALERT type 2 Indicator that the structure model may be wrong or deficient 1 ALERT type 3 Indicator that the structure quality may be low 0 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check
For related literature on hydrogen-bonding motifs, see Bernstein et al. (1995) and on values of bond lengths and angles, see Allen et al. (1987). For a related structure, see Ng et al. (2006).
4-Methoxybenzaldehyde (0.01 mol) and 3,4-dimethoxyacetophenone (0.01 mol) were stirred in 60 ml of methanol at room temperature. 10 ml of 10% aqueous NaOH solution was added and the mixture was stirred for 4 h. The precipitate was filtered, washed with water, dried and the crude product recrystallized from acetone. Crystals suitable for X-ray analysis were grown by slow evaporation of an acetone solution at room temperature.
H atoms were placed in calculated positions, with C—H distances in the range 0.93–0.96 Å. The Uiso values were constrained to be 1.5Ueq of the carrier atom for methyl H atoms and 1.2Ueq for the remaining H atoms.
We report here the molecular and supramolecular structure of the title compound, (I) (Figure 1).
The bond lengths and angles in (I) have normal values (Allen et al., 1987) and are comparable with those in a related structure (Ng et al., 2006). The molecule is slightly twisted about the C6—C7 bond with the dihedral angle between the two benzene rings (C1—C6 and C10—C15) being 17.49 (5)°. The methoxy groups attached at C3, C4 and C13 lie almost in the planes of the benzene rings to which they are attached (C1—C6 and C10—C15) [C17—O3—C4—C5 = 5.31 (13), C16—O2—C3—C2 = -3.87 (13) and C18—O4—C13—C12 = -0.56 (13)°].
The O1 atom is involved in both intramolecular and intermolecular interactions. An intramolecular C9—H9A···O1 interaction (Table 1 and Figure 1) generates an S(5) ring motif (Bernstein et al., 1995). In the crystal structure, the molecules are linked by intermolecular C11—H11A···O1i hydrogen bonds into cyclic centrosymmetric R22(14) dimers (Bernstein et al., 1995). The dimers are then interlinked by intermolecular C18—H18B···O1ii interactions. The crystal structure is further stablized by intermolecular π···π interactions involving the C1—C6 benzene ring (Centroid Cg1) with a Cg1···Cg1iv distance of 3.5267 (6)Å [symmetry code: (iv) 1 - x, 1 - y, -z]. In addition, the crystal packing is also stabilized by weak intermolecular C—H···π interactions involving C10—C15 (Centroid Cg2) (Table 1).
For related literature on hydrogen-bonding motifs, see Bernstein et al. (1995) and on values of bond lengths and angles, see Allen et al. (1987). For a related structure, see Ng et al. (2006).
Data collection: APEX2 (Bruker, 2005); cell refinement: APEX2; data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 1998); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003).
C18H18O4 | Z = 2 |
Mr = 298.32 | F(000) = 316 |
Triclinic, P1 | Dx = 1.338 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 8.6745 (2) Å | Cell parameters from 4878 reflections |
b = 8.8452 (2) Å | θ = 2.0–35.0° |
c = 11.3132 (2) Å | µ = 0.09 mm−1 |
α = 108.314 (1)° | T = 100 K |
β = 102.391 (1)° | Block, yellow |
γ = 107.237 (1)° | 0.59 × 0.51 × 0.25 mm |
V = 740.35 (3) Å3 |
Bruker SMART APEX2 CCD area-detector diffractometer | 6413 independent reflections |
Radiation source: fine-focus sealed tube | 5074 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.035 |
Detector resolution: 8.33 pixels mm-1 | θmax = 35.0°, θmin = 2.0° |
ω scans | h = −13→13 |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | k = −14→14 |
Tmin = 0.883, Tmax = 0.977 | l = −18→18 |
19236 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)] = 0.050 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.157 | H-atom parameters constrained |
S = 1.07 | w = 1/[σ2(Fo2) + (0.0906P)2 + 0.0805P] where P = (Fo2 + 2Fc2)/3 |
6413 reflections | (Δ/σ)max < 0.001 |
202 parameters | Δρmax = 0.34 e Å−3 |
0 restraints | Δρmin = −0.40 e Å−3 |
C18H18O4 | γ = 107.237 (1)° |
Mr = 298.32 | V = 740.35 (3) Å3 |
Triclinic, P1 | Z = 2 |
a = 8.6745 (2) Å | Mo Kα radiation |
b = 8.8452 (2) Å | µ = 0.09 mm−1 |
c = 11.3132 (2) Å | T = 100 K |
α = 108.314 (1)° | 0.59 × 0.51 × 0.25 mm |
β = 102.391 (1)° |
Bruker SMART APEX2 CCD area-detector diffractometer | 6413 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | 5074 reflections with I > 2σ(I) |
Tmin = 0.883, Tmax = 0.977 | Rint = 0.035 |
19236 measured reflections |
R[F2 > 2σ(F2)] = 0.050 | 0 restraints |
wR(F2) = 0.157 | H-atom parameters constrained |
S = 1.07 | Δρmax = 0.34 e Å−3 |
6413 reflections | Δρmin = −0.40 e Å−3 |
202 parameters |
Experimental. The data was collected with the Oxford Cyrosystem Cobra low-temperature attachment. |
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 | 0.60249 (9) | 0.91155 (10) | 0.34039 (7) | 0.02048 (14) | |
O2 | 0.68372 (9) | 0.50985 (10) | −0.19431 (7) | 0.02111 (14) | |
O3 | 0.86081 (9) | 0.58127 (10) | 0.04335 (7) | 0.02213 (15) | |
O4 | −0.18166 (9) | 1.28476 (10) | 0.31923 (7) | 0.02137 (15) | |
C1 | 0.47983 (11) | 0.77178 (12) | −0.01605 (9) | 0.01705 (16) | |
H1A | 0.3956 | 0.8150 | −0.0322 | 0.020* | |
C2 | 0.51867 (11) | 0.67691 (12) | −0.12132 (9) | 0.01841 (16) | |
H2A | 0.4607 | 0.6580 | −0.2073 | 0.022* | |
C3 | 0.64301 (11) | 0.61069 (11) | −0.09870 (9) | 0.01643 (15) | |
C4 | 0.73710 (11) | 0.64655 (12) | 0.03273 (9) | 0.01661 (15) | |
C5 | 0.69780 (11) | 0.74036 (12) | 0.13624 (9) | 0.01642 (15) | |
H5A | 0.7587 | 0.7633 | 0.2226 | 0.020* | |
C6 | 0.56670 (10) | 0.80193 (11) | 0.11301 (8) | 0.01507 (15) | |
C7 | 0.52360 (11) | 0.89143 (11) | 0.22823 (8) | 0.01578 (15) | |
C8 | 0.38377 (11) | 0.95373 (12) | 0.20778 (9) | 0.01766 (16) | |
H8A | 0.3353 | 0.9534 | 0.1259 | 0.021* | |
C9 | 0.32676 (11) | 1.01090 (12) | 0.30768 (9) | 0.01699 (15) | |
H9A | 0.3795 | 1.0073 | 0.3869 | 0.020* | |
C10 | 0.19162 (10) | 1.07816 (11) | 0.30654 (8) | 0.01582 (15) | |
C11 | 0.14495 (11) | 1.12011 (12) | 0.41977 (9) | 0.01748 (16) | |
H11A | 0.1991 | 1.1027 | 0.4917 | 0.021* | |
C12 | 0.01963 (11) | 1.18722 (12) | 0.42755 (9) | 0.01821 (16) | |
H12A | −0.0104 | 1.2132 | 0.5034 | 0.022* | |
C13 | −0.06058 (11) | 1.21513 (12) | 0.32035 (8) | 0.01630 (15) | |
C14 | −0.01674 (11) | 1.17283 (12) | 0.20553 (9) | 0.01796 (16) | |
H14A | −0.0707 | 1.1910 | 0.1339 | 0.022* | |
C15 | 0.10662 (11) | 1.10416 (12) | 0.19840 (9) | 0.01709 (15) | |
H15A | 0.1338 | 1.0748 | 0.1213 | 0.021* | |
C16 | 0.58389 (14) | 0.46028 (14) | −0.32809 (9) | 0.02451 (19) | |
H16A | 0.6087 | 0.3718 | −0.3856 | 0.037* | |
H16B | 0.6115 | 0.5590 | −0.3502 | 0.037* | |
H16D | 0.4642 | 0.4166 | −0.3386 | 0.037* | |
C17 | 0.94934 (12) | 0.59903 (13) | 0.17186 (10) | 0.02154 (18) | |
H17A | 1.0356 | 0.5522 | 0.1670 | 0.032* | |
H17D | 0.8694 | 0.5375 | 0.2042 | 0.032* | |
H17B | 1.0027 | 0.7193 | 0.2309 | 0.032* | |
C18 | −0.22757 (12) | 1.32908 (13) | 0.43559 (9) | 0.02108 (17) | |
H18D | −0.3110 | 1.3791 | 0.4243 | 0.032* | |
H18A | −0.1274 | 1.4112 | 0.5102 | 0.032* | |
H18B | −0.2752 | 1.2268 | 0.4504 | 0.032* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0224 (3) | 0.0271 (3) | 0.0163 (3) | 0.0155 (3) | 0.0059 (2) | 0.0091 (3) |
O2 | 0.0253 (3) | 0.0256 (3) | 0.0189 (3) | 0.0158 (3) | 0.0120 (2) | 0.0086 (3) |
O3 | 0.0213 (3) | 0.0314 (4) | 0.0223 (3) | 0.0196 (3) | 0.0094 (2) | 0.0117 (3) |
O4 | 0.0239 (3) | 0.0321 (4) | 0.0195 (3) | 0.0212 (3) | 0.0110 (2) | 0.0124 (3) |
C1 | 0.0180 (3) | 0.0192 (4) | 0.0180 (3) | 0.0113 (3) | 0.0065 (3) | 0.0087 (3) |
C2 | 0.0213 (4) | 0.0216 (4) | 0.0168 (3) | 0.0127 (3) | 0.0071 (3) | 0.0089 (3) |
C3 | 0.0186 (3) | 0.0181 (4) | 0.0174 (3) | 0.0100 (3) | 0.0093 (3) | 0.0083 (3) |
C4 | 0.0155 (3) | 0.0191 (4) | 0.0201 (4) | 0.0102 (3) | 0.0079 (3) | 0.0095 (3) |
C5 | 0.0156 (3) | 0.0193 (4) | 0.0177 (3) | 0.0104 (3) | 0.0059 (3) | 0.0082 (3) |
C6 | 0.0156 (3) | 0.0163 (3) | 0.0164 (3) | 0.0088 (3) | 0.0065 (3) | 0.0073 (3) |
C7 | 0.0160 (3) | 0.0172 (4) | 0.0172 (3) | 0.0095 (3) | 0.0062 (3) | 0.0076 (3) |
C8 | 0.0174 (3) | 0.0213 (4) | 0.0177 (3) | 0.0116 (3) | 0.0061 (3) | 0.0083 (3) |
C9 | 0.0162 (3) | 0.0195 (4) | 0.0184 (3) | 0.0101 (3) | 0.0062 (3) | 0.0084 (3) |
C10 | 0.0149 (3) | 0.0181 (4) | 0.0166 (3) | 0.0090 (3) | 0.0058 (3) | 0.0071 (3) |
C11 | 0.0188 (3) | 0.0216 (4) | 0.0159 (3) | 0.0119 (3) | 0.0064 (3) | 0.0084 (3) |
C12 | 0.0198 (3) | 0.0239 (4) | 0.0160 (3) | 0.0136 (3) | 0.0080 (3) | 0.0085 (3) |
C13 | 0.0163 (3) | 0.0192 (4) | 0.0171 (3) | 0.0110 (3) | 0.0070 (3) | 0.0073 (3) |
C14 | 0.0187 (3) | 0.0237 (4) | 0.0165 (3) | 0.0128 (3) | 0.0073 (3) | 0.0093 (3) |
C15 | 0.0177 (3) | 0.0215 (4) | 0.0164 (3) | 0.0115 (3) | 0.0079 (3) | 0.0081 (3) |
C16 | 0.0313 (5) | 0.0269 (5) | 0.0176 (4) | 0.0143 (4) | 0.0105 (3) | 0.0076 (3) |
C17 | 0.0193 (4) | 0.0255 (4) | 0.0237 (4) | 0.0140 (3) | 0.0064 (3) | 0.0104 (4) |
C18 | 0.0220 (4) | 0.0261 (4) | 0.0193 (4) | 0.0154 (3) | 0.0094 (3) | 0.0072 (3) |
O1—C7 | 1.2342 (10) | C9—H9A | 0.9300 |
O2—C3 | 1.3544 (11) | C10—C11 | 1.3983 (12) |
O2—C16 | 1.4241 (12) | C10—C15 | 1.4083 (11) |
O3—C4 | 1.3620 (10) | C11—C12 | 1.3902 (12) |
O3—C17 | 1.4262 (12) | C11—H11A | 0.9300 |
O4—C13 | 1.3657 (10) | C12—C13 | 1.3942 (12) |
O4—C18 | 1.4278 (11) | C12—H12A | 0.9300 |
C1—C6 | 1.3910 (12) | C13—C14 | 1.4010 (13) |
C1—C2 | 1.3956 (13) | C14—C15 | 1.3828 (12) |
C1—H1A | 0.9300 | C14—H14A | 0.9300 |
C2—C3 | 1.3864 (12) | C15—H15A | 0.9300 |
C2—H2A | 0.9300 | C16—H16A | 0.9600 |
C3—C4 | 1.4167 (12) | C16—H16B | 0.9600 |
C4—C5 | 1.3800 (13) | C16—H16D | 0.9600 |
C5—C6 | 1.4098 (11) | C17—H17A | 0.9600 |
C5—H5A | 0.9300 | C17—H17D | 0.9600 |
C6—C7 | 1.4838 (12) | C17—H17B | 0.9600 |
C7—C8 | 1.4779 (12) | C18—H18D | 0.9600 |
C8—C9 | 1.3441 (13) | C18—H18A | 0.9600 |
C8—H8A | 0.9300 | C18—H18B | 0.9600 |
C9—C10 | 1.4628 (12) | ||
C3—O2—C16 | 117.14 (7) | C12—C11—C10 | 121.69 (7) |
C4—O3—C17 | 117.36 (7) | C12—C11—H11A | 119.2 |
C13—O4—C18 | 116.83 (7) | C10—C11—H11A | 119.2 |
C6—C1—C2 | 120.19 (8) | C11—C12—C13 | 119.27 (8) |
C6—C1—H1A | 119.9 | C11—C12—H12A | 120.4 |
C2—C1—H1A | 119.9 | C13—C12—H12A | 120.4 |
C3—C2—C1 | 120.51 (8) | O4—C13—C12 | 123.92 (8) |
C3—C2—H2A | 119.7 | O4—C13—C14 | 116.08 (7) |
C1—C2—H2A | 119.7 | C12—C13—C14 | 120.00 (8) |
O2—C3—C2 | 124.98 (8) | C15—C14—C13 | 120.17 (8) |
O2—C3—C4 | 115.27 (7) | C15—C14—H14A | 119.9 |
C2—C3—C4 | 119.75 (8) | C13—C14—H14A | 119.9 |
O3—C4—C5 | 126.05 (8) | C14—C15—C10 | 120.73 (8) |
O3—C4—C3 | 114.64 (8) | C14—C15—H15A | 119.6 |
C5—C4—C3 | 119.30 (7) | C10—C15—H15A | 119.6 |
C4—C5—C6 | 120.97 (8) | O2—C16—H16A | 109.5 |
C4—C5—H5A | 119.5 | O2—C16—H16B | 109.5 |
C6—C5—H5A | 119.5 | H16A—C16—H16B | 109.5 |
C1—C6—C5 | 119.19 (8) | O2—C16—H16D | 109.5 |
C1—C6—C7 | 122.84 (7) | H16A—C16—H16D | 109.5 |
C5—C6—C7 | 117.94 (7) | H16B—C16—H16D | 109.5 |
O1—C7—C8 | 120.14 (8) | O3—C17—H17A | 109.5 |
O1—C7—C6 | 120.16 (7) | O3—C17—H17D | 109.5 |
C8—C7—C6 | 119.69 (7) | H17A—C17—H17D | 109.5 |
C9—C8—C7 | 119.90 (8) | O3—C17—H17B | 109.5 |
C9—C8—H8A | 120.1 | H17A—C17—H17B | 109.5 |
C7—C8—H8A | 120.1 | H17D—C17—H17B | 109.5 |
C8—C9—C10 | 127.71 (8) | O4—C18—H18D | 109.5 |
C8—C9—H9A | 116.1 | O4—C18—H18A | 109.5 |
C10—C9—H9A | 116.1 | H18D—C18—H18A | 109.5 |
C11—C10—C15 | 118.12 (7) | O4—C18—H18B | 109.5 |
C11—C10—C9 | 118.06 (7) | H18D—C18—H18B | 109.5 |
C15—C10—C9 | 123.82 (8) | H18A—C18—H18B | 109.5 |
C6—C1—C2—C3 | 0.48 (14) | C1—C6—C7—C8 | −0.50 (13) |
C16—O2—C3—C2 | −3.87 (13) | C5—C6—C7—C8 | −178.33 (8) |
C16—O2—C3—C4 | 175.61 (8) | O1—C7—C8—C9 | −9.03 (14) |
C1—C2—C3—O2 | 176.43 (8) | C6—C7—C8—C9 | 169.93 (8) |
C1—C2—C3—C4 | −3.03 (13) | C7—C8—C9—C10 | 179.49 (8) |
C17—O3—C4—C5 | 5.31 (13) | C8—C9—C10—C11 | 175.84 (9) |
C17—O3—C4—C3 | −174.36 (8) | C8—C9—C10—C15 | −4.59 (15) |
O2—C3—C4—O3 | 3.21 (11) | C15—C10—C11—C12 | −0.60 (14) |
C2—C3—C4—O3 | −177.28 (8) | C9—C10—C11—C12 | 179.00 (8) |
O2—C3—C4—C5 | −176.47 (8) | C10—C11—C12—C13 | −0.64 (14) |
C2—C3—C4—C5 | 3.04 (13) | C18—O4—C13—C12 | −0.56 (13) |
O3—C4—C5—C6 | 179.83 (8) | C18—O4—C13—C14 | −179.84 (8) |
C3—C4—C5—C6 | −0.53 (13) | C11—C12—C13—O4 | −178.15 (8) |
C2—C1—C6—C5 | 2.03 (13) | C11—C12—C13—C14 | 1.10 (14) |
C2—C1—C6—C7 | −175.77 (8) | O4—C13—C14—C15 | 178.99 (8) |
C4—C5—C6—C1 | −2.00 (13) | C12—C13—C14—C15 | −0.31 (14) |
C4—C5—C6—C7 | 175.91 (8) | C13—C14—C15—C10 | −0.96 (14) |
C1—C6—C7—O1 | 178.46 (8) | C11—C10—C15—C14 | 1.40 (13) |
C5—C6—C7—O1 | 0.63 (13) | C9—C10—C15—C14 | −178.17 (8) |
D—H···A | D—H | H···A | D···A | D—H···A |
C9—H9A···O1 | 0.93 | 2.42 | 2.775 (1) | 102 |
C11—H11A···O1i | 0.93 | 2.34 | 3.245 (1) | 165 |
C18—H18B···O1ii | 0.96 | 2.44 | 3.250 (2) | 142 |
C5—H5A···Cg2iii | 0.93 | 3.30 | 3.604 (1) | 102 |
Symmetry codes: (i) −x+1, −y+2, −z+1; (ii) x−1, y, z; (iii) x+1, y, z. |
Experimental details
Crystal data | |
Chemical formula | C18H18O4 |
Mr | 298.32 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 100 |
a, b, c (Å) | 8.6745 (2), 8.8452 (2), 11.3132 (2) |
α, β, γ (°) | 108.314 (1), 102.391 (1), 107.237 (1) |
V (Å3) | 740.35 (3) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.59 × 0.51 × 0.25 |
Data collection | |
Diffractometer | Bruker SMART APEX2 CCD area-detector |
Absorption correction | Multi-scan (SADABS; Bruker, 2005) |
Tmin, Tmax | 0.883, 0.977 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 19236, 6413, 5074 |
Rint | 0.035 |
(sin θ/λ)max (Å−1) | 0.807 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.050, 0.157, 1.07 |
No. of reflections | 6413 |
No. of parameters | 202 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.34, −0.40 |
Computer programs: APEX2 (Bruker, 2005), APEX2, SAINT (Bruker, 2005), SHELXTL (Sheldrick, 1998), SHELXTL and PLATON (Spek, 2003).
D—H···A | D—H | H···A | D···A | D—H···A |
C9—H9A···O1 | 0.93 | 2.42 | 2.775 (1) | 102 |
C11—H11A···O1i | 0.93 | 2.34 | 3.245 (1) | 165 |
C18—H18B···O1ii | 0.96 | 2.44 | 3.250 (2) | 142 |
C5—H5A···Cg2iii | 0.93 | 3.30 | 3.604 (1) | 102 |
Symmetry codes: (i) −x+1, −y+2, −z+1; (ii) x−1, y, z; (iii) x+1, y, z. |
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We report here the molecular and supramolecular structure of the title compound, (I) (Figure 1).
The bond lengths and angles in (I) have normal values (Allen et al., 1987) and are comparable with those in a related structure (Ng et al., 2006). The molecule is slightly twisted about the C6—C7 bond with the dihedral angle between the two benzene rings (C1—C6 and C10—C15) being 17.49 (5)°. The methoxy groups attached at C3, C4 and C13 lie almost in the planes of the benzene rings to which they are attached (C1—C6 and C10—C15) [C17—O3—C4—C5 = 5.31 (13), C16—O2—C3—C2 = -3.87 (13) and C18—O4—C13—C12 = -0.56 (13)°].
The O1 atom is involved in both intramolecular and intermolecular interactions. An intramolecular C9—H9A···O1 interaction (Table 1 and Figure 1) generates an S(5) ring motif (Bernstein et al., 1995). In the crystal structure, the molecules are linked by intermolecular C11—H11A···O1i hydrogen bonds into cyclic centrosymmetric R22(14) dimers (Bernstein et al., 1995). The dimers are then interlinked by intermolecular C18—H18B···O1ii interactions. The crystal structure is further stablized by intermolecular π···π interactions involving the C1—C6 benzene ring (Centroid Cg1) with a Cg1···Cg1iv distance of 3.5267 (6)Å [symmetry code: (iv) 1 - x, 1 - y, -z]. In addition, the crystal packing is also stabilized by weak intermolecular C—H···π interactions involving C10—C15 (Centroid Cg2) (Table 1).