organic compounds
(E)-1-(1,3-Benzodioxol-5-yl)-3-(2,4,5-trimethoxyphenyl)prop-2-en-1-one
aDepartment of Physics, Shri Pillappa College of Engineering, Bengaluru 560 089, India, bDepartment of Physics, Prist University, Vallam, Tanjavur 513 403, India, cInstitution of Excellence, University of Mysore, Manasagangotri, Mysuru 570 006, India, dDepartment of Chemistry, Yuvaraja's College, University of Mysore, Mysuru 570 005, India, eDepartment of Studies in Physics, University of Mysore, Manasagangotri, Mysuru 570 006, India, and fDepartment of Physics, Acharya Institute of Technology, Soldevanahalli, Bengaluru 560 107, India
*Correspondence e-mail: naveen@ioe.uni-mysore.ac.in, manjunathhr@acharya.ac.in
The molecule of the title compound C19H18O6, adopts an E conformation about the C=C double bond and the C—C=C—C torsion angle is −179.30 (16)°. The molecule is nearly planar, as indicated by the dihedral angle of 6.99 (6)° between the benzene ring and the benzodioxalane ring. In the crystal, molecules are linked via weak C—H⋯O hydrogen bonds, forming zigzag chains propagating along the b axis.
Keywords: crystal structure; bis-chalcone; weak C—H⋯O hydrogen bonds.
CCDC reference: 1523870
Structure description
et al., 2016). and their derivatives demonstrate a wide range of biological activities such as anti-diabetic, antineoplastic, antihypertensive, anti-inflammatory, antimalarial, antioxidant and antifungal activities (Mahapatra et al., 2015). The α,β-unsaturated carbonyl system of made them useful building blocks in organic synthesis. They have been efficiently employed as precursors in the syntheses of biologically potent benzothiazepines (Manjunath et al., 2014). In view of diversified applications of and as a part of our ongoing work on such molecules (Tejkiran et al., 2016), we report herein the synthesis and of the title compound.
form the central core for the construction of a variety of bioactive compounds. The usual method for the synthesis of involves the condensation of an aromatic aldehyde and an aromatic ketone in the presence of aqueous alkaline bases (NaveenThe molecular structure of the title compound is shown in Fig. 1. The molecule is nearly planar with a dihedral angle of 6.99 (6)° between the benzene and benzodioxalane rings that are bridged by the olefinic double bond. This value is less than the value of 19.13 (15)° between the aromatic rings in the related chalcone derivative (E)-3-(2,3-dichlorophenyl)-1-(4-fluorophenyl)prop-2-en-1-one (Naveen et al., 2016). The trans conformation of the C7=C8 double bond in the central enone group is confirmed by the value of the C1—C7=C8—C9 torsion angle −179.30 (16)°. The methoxy groups at C3, C4 and C6 are nearly coplanar with the C1–C6 benzene ring. In the crystal, the molecules are linked via weak C—H⋯O hydrogen bonds (Table 1), forming zigzag chains parallel to the b axis (Fig. 2).
Synthesis and crystallization
A mixture of 2,4,5-trimethoxybenzaldehyde (5 mmol), 1-(benzo[d][1,3]dioxol-5-yl)ethanone (5 mmol) and sodium hydroxide (5 mmol) in 95% ethyl alcohol (25 ml) was stirred at room temperature for 3 h. The progress of the reaction was monitored by TLC. After completion of the reaction, the mixture was poured into ice cold water and kept in the refrigerator overnight. The solid that formed was filtered, and washed with cold hydrochloric acid (5%). Yellow rectangular crystals were obtained by slow evaporation of a solution in methanol (yield 89%, m.p. 399–401 K).
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2Structural data
CCDC reference: 1523870
https://doi.org/10.1107/S2414314616020265/rz4009sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314616020265/rz4009Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2414314616020265/rz4009Isup3.cml
Data collection: APEX2 (Bruker, 2011); cell
SAINT (Bruker, 2011); data reduction: SAINT (Bruker, 2011); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: Mercury (Macrae et al., 2008).C19H18O6 | F(000) = 720 |
Mr = 342.33 | Dx = 1.455 Mg m−3 |
Monoclinic, P21/n | Cu Kα radiation, λ = 1.54178 Å |
Hall symbol: -P 2yn | Cell parameters from 2568 reflections |
a = 10.9127 (2) Å | θ = 5.3–64.5° |
b = 13.4406 (3) Å | µ = 0.91 mm−1 |
c = 11.1011 (2) Å | T = 296 K |
β = 106.287 (1)° | Block, yellow |
V = 1562.89 (5) Å3 | 0.29 × 0.26 × 0.24 mm |
Z = 4 |
Bruker X8 Proteum diffractometer | 2568 independent reflections |
Radiation source: Bruker MicroStar microfocus rotating anode | 2283 reflections with I > 2σ(I) |
Helios multilayer optics monochromator | Rint = 0.054 |
Detector resolution: 18.4 pixels mm-1 | θmax = 64.5°, θmin = 5.3° |
φ and ω scans | h = −11→12 |
Absorption correction: multi-scan (SADABS; Bruker, 2011) | k = −15→15 |
Tmin = 0.779, Tmax = 0.812 | l = −12→12 |
12593 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)] = 0.046 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.145 | H-atom parameters constrained |
S = 1.09 | w = 1/[σ2(Fo2) + (0.1062P)2 + 0.0554P] where P = (Fo2 + 2Fc2)/3 |
2568 reflections | (Δ/σ)max = 0.001 |
229 parameters | Δρmax = 0.30 e Å−3 |
0 restraints | Δρmin = −0.30 e Å−3 |
Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell esds are taken into account in the estimation of distances, angles and torsion angles |
Refinement. Refinement on F2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > 2sigma(F2) is used only for calculating -R-factor-obs 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 | 0.91113 (10) | 1.12891 (8) | 1.26097 (10) | 0.0195 (3) | |
O2 | 1.03766 (10) | 1.20902 (8) | 1.12453 (10) | 0.0211 (3) | |
O3 | 0.78978 (11) | 1.03030 (9) | 0.75876 (10) | 0.0253 (4) | |
O4 | 0.48629 (11) | 0.80424 (9) | 0.74724 (10) | 0.0256 (4) | |
O5 | 0.11332 (10) | 0.58892 (9) | 0.77554 (10) | 0.0225 (3) | |
O6 | 0.11852 (11) | 0.57683 (9) | 0.98559 (11) | 0.0239 (4) | |
C1 | 0.75134 (14) | 1.00721 (11) | 0.95591 (15) | 0.0168 (5) | |
C2 | 0.77990 (14) | 1.03224 (11) | 1.08453 (14) | 0.0166 (5) | |
C3 | 0.87534 (14) | 1.09951 (12) | 1.13825 (14) | 0.0170 (5) | |
C4 | 0.94560 (14) | 1.14401 (11) | 1.06326 (15) | 0.0173 (5) | |
C5 | 0.91856 (15) | 1.12160 (11) | 0.93735 (15) | 0.0186 (5) | |
C6 | 0.82250 (15) | 1.05351 (12) | 0.88408 (14) | 0.0179 (5) | |
C7 | 0.65492 (15) | 0.93450 (11) | 0.89609 (15) | 0.0179 (5) | |
C8 | 0.57013 (15) | 0.88508 (11) | 0.94087 (15) | 0.0184 (5) | |
C9 | 0.48403 (14) | 0.81406 (12) | 0.85739 (15) | 0.0185 (5) | |
C10 | 0.39080 (14) | 0.75351 (11) | 0.90211 (14) | 0.0167 (4) | |
C11 | 0.29852 (14) | 0.70065 (11) | 0.80904 (14) | 0.0180 (5) | |
C12 | 0.21113 (14) | 0.64612 (11) | 0.84800 (15) | 0.0174 (5) | |
C13 | 0.04917 (16) | 0.54733 (12) | 0.86066 (15) | 0.0218 (5) | |
C14 | 0.21371 (15) | 0.63905 (11) | 0.97324 (15) | 0.0178 (5) | |
C15 | 0.30402 (15) | 0.68775 (12) | 1.06610 (15) | 0.0198 (5) | |
C16 | 0.39221 (15) | 0.74662 (12) | 1.02786 (15) | 0.0183 (5) | |
C17 | 0.84472 (16) | 1.08758 (13) | 1.34227 (15) | 0.0234 (5) | |
C18 | 1.11336 (15) | 1.25347 (13) | 1.05277 (15) | 0.0227 (5) | |
C19 | 0.87351 (16) | 1.06180 (12) | 0.68832 (15) | 0.0226 (5) | |
H2 | 0.73360 | 1.00290 | 1.13380 | 0.0200* | |
H5 | 0.96430 | 1.15180 | 0.88820 | 0.0220* | |
H7 | 0.65140 | 0.91980 | 0.81330 | 0.0220* | |
H8 | 0.56590 | 0.89550 | 1.02240 | 0.0220* | |
H11 | 0.29740 | 0.70290 | 0.72500 | 0.0210* | |
H13A | −0.03790 | 0.57170 | 0.84070 | 0.0260* | |
H13B | 0.04680 | 0.47540 | 0.85400 | 0.0260* | |
H15 | 0.30640 | 0.68190 | 1.15020 | 0.0240* | |
H16 | 0.45330 | 0.78200 | 1.08790 | 0.0220* | |
H17A | 0.75530 | 1.10180 | 1.31010 | 0.0350* | |
H17B | 0.87660 | 1.11610 | 1.42440 | 0.0350* | |
H17C | 0.85740 | 1.01680 | 1.34720 | 0.0350* | |
H18A | 1.15250 | 1.20220 | 1.01600 | 0.0340* | |
H18B | 1.17840 | 1.29410 | 1.10660 | 0.0340* | |
H18C | 1.06000 | 1.29390 | 0.98760 | 0.0340* | |
H19A | 0.87440 | 1.13320 | 0.68500 | 0.0340* | |
H19B | 0.84450 | 1.03560 | 0.60470 | 0.0340* | |
H19C | 0.95820 | 1.03790 | 0.72780 | 0.0340* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0220 (6) | 0.0216 (6) | 0.0148 (6) | −0.0055 (4) | 0.0049 (5) | −0.0011 (4) |
O2 | 0.0203 (6) | 0.0225 (6) | 0.0193 (6) | −0.0070 (4) | 0.0035 (5) | −0.0002 (4) |
O3 | 0.0311 (7) | 0.0300 (7) | 0.0164 (6) | −0.0111 (5) | 0.0094 (5) | −0.0039 (5) |
O4 | 0.0303 (7) | 0.0282 (7) | 0.0202 (6) | −0.0094 (5) | 0.0104 (5) | −0.0053 (5) |
O5 | 0.0215 (6) | 0.0247 (6) | 0.0206 (6) | −0.0080 (5) | 0.0047 (5) | −0.0030 (5) |
O6 | 0.0209 (6) | 0.0287 (7) | 0.0230 (7) | −0.0076 (5) | 0.0077 (5) | 0.0005 (5) |
C1 | 0.0151 (8) | 0.0146 (8) | 0.0198 (8) | 0.0023 (6) | 0.0033 (6) | 0.0010 (6) |
C2 | 0.0159 (8) | 0.0152 (8) | 0.0194 (8) | 0.0004 (6) | 0.0061 (6) | 0.0013 (6) |
C3 | 0.0166 (8) | 0.0177 (8) | 0.0162 (8) | 0.0020 (6) | 0.0037 (6) | 0.0009 (6) |
C4 | 0.0151 (8) | 0.0145 (8) | 0.0211 (9) | 0.0020 (6) | 0.0032 (6) | 0.0016 (6) |
C5 | 0.0178 (8) | 0.0178 (8) | 0.0216 (9) | 0.0014 (6) | 0.0080 (6) | 0.0038 (6) |
C6 | 0.0189 (8) | 0.0187 (8) | 0.0158 (8) | 0.0024 (6) | 0.0044 (7) | −0.0006 (6) |
C7 | 0.0183 (8) | 0.0166 (8) | 0.0184 (8) | 0.0045 (6) | 0.0043 (6) | 0.0003 (6) |
C8 | 0.0187 (8) | 0.0171 (8) | 0.0190 (8) | 0.0019 (6) | 0.0046 (7) | −0.0004 (6) |
C9 | 0.0190 (8) | 0.0164 (8) | 0.0205 (9) | 0.0043 (6) | 0.0063 (7) | 0.0011 (6) |
C10 | 0.0165 (8) | 0.0131 (7) | 0.0202 (8) | 0.0033 (6) | 0.0046 (6) | 0.0002 (6) |
C11 | 0.0206 (8) | 0.0167 (8) | 0.0167 (8) | 0.0022 (6) | 0.0054 (7) | 0.0000 (6) |
C12 | 0.0159 (7) | 0.0141 (8) | 0.0214 (9) | 0.0016 (6) | 0.0039 (6) | −0.0020 (6) |
C13 | 0.0205 (8) | 0.0237 (9) | 0.0226 (9) | −0.0055 (7) | 0.0082 (7) | −0.0034 (7) |
C14 | 0.0164 (8) | 0.0153 (8) | 0.0228 (9) | 0.0031 (6) | 0.0073 (6) | 0.0018 (6) |
C15 | 0.0205 (8) | 0.0212 (9) | 0.0178 (8) | 0.0021 (6) | 0.0054 (7) | 0.0013 (6) |
C16 | 0.0168 (8) | 0.0158 (8) | 0.0206 (9) | 0.0025 (6) | 0.0025 (6) | −0.0009 (6) |
C17 | 0.0271 (9) | 0.0264 (9) | 0.0177 (9) | −0.0070 (7) | 0.0079 (7) | −0.0006 (6) |
C18 | 0.0196 (9) | 0.0225 (9) | 0.0266 (9) | −0.0038 (7) | 0.0076 (7) | 0.0011 (7) |
C19 | 0.0281 (9) | 0.0234 (9) | 0.0187 (9) | −0.0001 (7) | 0.0107 (7) | 0.0005 (6) |
O1—C3 | 1.3661 (18) | C11—C12 | 1.366 (2) |
O1—C17 | 1.420 (2) | C12—C14 | 1.386 (2) |
O2—C4 | 1.3609 (19) | C14—C15 | 1.376 (2) |
O2—C18 | 1.429 (2) | C15—C16 | 1.401 (2) |
O3—C6 | 1.3717 (18) | C2—H2 | 0.9300 |
O3—C19 | 1.424 (2) | C5—H5 | 0.9300 |
O4—C9 | 1.2370 (19) | C7—H7 | 0.9300 |
O5—C12 | 1.3769 (19) | C8—H8 | 0.9300 |
O5—C13 | 1.438 (2) | C11—H11 | 0.9300 |
O6—C13 | 1.437 (2) | C13—H13A | 0.9700 |
O6—C14 | 1.370 (2) | C13—H13B | 0.9700 |
C1—C2 | 1.414 (2) | C15—H15 | 0.9300 |
C1—C6 | 1.405 (2) | C16—H16 | 0.9300 |
C1—C7 | 1.453 (2) | C17—H17A | 0.9600 |
C2—C3 | 1.382 (2) | C17—H17B | 0.9600 |
C3—C4 | 1.413 (2) | C17—H17C | 0.9600 |
C4—C5 | 1.379 (2) | C18—H18A | 0.9600 |
C5—C6 | 1.392 (2) | C18—H18B | 0.9600 |
C7—C8 | 1.343 (2) | C18—H18C | 0.9600 |
C8—C9 | 1.471 (2) | C19—H19A | 0.9600 |
C9—C10 | 1.492 (2) | C19—H19B | 0.9600 |
C10—C11 | 1.415 (2) | C19—H19C | 0.9600 |
C10—C16 | 1.395 (2) | ||
C3—O1—C17 | 117.82 (12) | C1—C2—H2 | 119.00 |
C4—O2—C18 | 116.80 (12) | C3—C2—H2 | 119.00 |
C6—O3—C19 | 117.70 (13) | C4—C5—H5 | 120.00 |
C12—O5—C13 | 105.89 (12) | C6—C5—H5 | 120.00 |
C13—O6—C14 | 106.30 (12) | C1—C7—H7 | 115.00 |
C2—C1—C6 | 117.87 (14) | C8—C7—H7 | 115.00 |
C2—C1—C7 | 123.22 (14) | C7—C8—H8 | 121.00 |
C6—C1—C7 | 118.90 (14) | C9—C8—H8 | 121.00 |
C1—C2—C3 | 121.16 (14) | C10—C11—H11 | 121.00 |
O1—C3—C2 | 126.14 (14) | C12—C11—H11 | 121.00 |
O1—C3—C4 | 114.49 (14) | O5—C13—H13A | 110.00 |
C2—C3—C4 | 119.38 (14) | O5—C13—H13B | 110.00 |
O2—C4—C3 | 115.07 (14) | O6—C13—H13A | 110.00 |
O2—C4—C5 | 124.41 (14) | O6—C13—H13B | 110.00 |
C3—C4—C5 | 120.51 (14) | H13A—C13—H13B | 108.00 |
C4—C5—C6 | 119.73 (15) | C14—C15—H15 | 122.00 |
O3—C6—C1 | 116.54 (14) | C16—C15—H15 | 122.00 |
O3—C6—C5 | 122.08 (14) | C10—C16—H16 | 119.00 |
C1—C6—C5 | 121.35 (14) | C15—C16—H16 | 119.00 |
C1—C7—C8 | 130.50 (15) | O1—C17—H17A | 109.00 |
C7—C8—C9 | 118.20 (14) | O1—C17—H17B | 110.00 |
O4—C9—C8 | 120.37 (15) | O1—C17—H17C | 109.00 |
O4—C9—C10 | 118.37 (14) | H17A—C17—H17B | 110.00 |
C8—C9—C10 | 121.25 (14) | H17A—C17—H17C | 109.00 |
C9—C10—C11 | 116.28 (13) | H17B—C17—H17C | 109.00 |
C9—C10—C16 | 123.50 (14) | O2—C18—H18A | 109.00 |
C11—C10—C16 | 120.21 (14) | O2—C18—H18B | 109.00 |
C10—C11—C12 | 117.09 (14) | O2—C18—H18C | 109.00 |
O5—C12—C11 | 127.62 (14) | H18A—C18—H18B | 109.00 |
O5—C12—C14 | 110.01 (13) | H18A—C18—H18C | 110.00 |
C11—C12—C14 | 122.34 (15) | H18B—C18—H18C | 109.00 |
O5—C13—O6 | 107.78 (13) | O3—C19—H19A | 109.00 |
O6—C14—C12 | 109.85 (14) | O3—C19—H19B | 109.00 |
O6—C14—C15 | 128.27 (15) | O3—C19—H19C | 109.00 |
C12—C14—C15 | 121.86 (15) | H19A—C19—H19B | 109.00 |
C14—C15—C16 | 116.77 (15) | H19A—C19—H19C | 109.00 |
C10—C16—C15 | 121.68 (15) | H19B—C19—H19C | 109.00 |
C17—O1—C3—C2 | −0.3 (2) | C2—C3—C4—C5 | 0.7 (2) |
C17—O1—C3—C4 | 179.87 (13) | O2—C4—C5—C6 | 179.72 (14) |
C18—O2—C4—C3 | 178.25 (13) | C3—C4—C5—C6 | −0.9 (2) |
C18—O2—C4—C5 | −2.4 (2) | C4—C5—C6—O3 | 178.47 (15) |
C19—O3—C6—C1 | −169.19 (14) | C4—C5—C6—C1 | 0.4 (2) |
C19—O3—C6—C5 | 12.7 (2) | C1—C7—C8—C9 | −179.30 (16) |
C13—O5—C12—C11 | −179.87 (15) | C7—C8—C9—O4 | −3.4 (2) |
C13—O5—C12—C14 | 2.25 (17) | C7—C8—C9—C10 | 177.58 (15) |
C12—O5—C13—O6 | −3.93 (16) | O4—C9—C10—C11 | −9.5 (2) |
C14—O6—C13—O5 | 4.16 (16) | O4—C9—C10—C16 | 169.88 (15) |
C13—O6—C14—C12 | −2.82 (17) | C8—C9—C10—C11 | 169.58 (14) |
C13—O6—C14—C15 | 178.86 (16) | C8—C9—C10—C16 | −11.1 (2) |
C6—C1—C2—C3 | −0.5 (2) | C9—C10—C11—C12 | −178.97 (14) |
C7—C1—C2—C3 | 177.87 (15) | C16—C10—C11—C12 | 1.7 (2) |
C2—C1—C6—O3 | −177.88 (14) | C9—C10—C16—C15 | −179.06 (15) |
C2—C1—C6—C5 | 0.3 (2) | C11—C10—C16—C15 | 0.2 (2) |
C7—C1—C6—O3 | 3.7 (2) | C10—C11—C12—O5 | −179.86 (14) |
C7—C1—C6—C5 | −178.14 (15) | C10—C11—C12—C14 | −2.2 (2) |
C2—C1—C7—C8 | 6.3 (3) | O5—C12—C14—O6 | 0.37 (18) |
C6—C1—C7—C8 | −175.42 (17) | O5—C12—C14—C15 | 178.81 (14) |
C1—C2—C3—O1 | −179.85 (14) | C11—C12—C14—O6 | −177.65 (14) |
C1—C2—C3—C4 | 0.0 (2) | C11—C12—C14—C15 | 0.8 (2) |
O1—C3—C4—O2 | 0.0 (2) | O6—C14—C15—C16 | 179.32 (15) |
O1—C3—C4—C5 | −179.42 (14) | C12—C14—C15—C16 | 1.2 (2) |
C2—C3—C4—O2 | −179.86 (14) | C14—C15—C16—C10 | −1.7 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
C13—H13B···O4i | 0.97 | 2.54 | 3.464 (2) | 159 |
Symmetry code: (i) −x+1/2, y−1/2, −z+3/2. |
Acknowledgements
The authors are grateful to the Institution of Excellence, Vijnana Bhavana, University of Mysore, India, for providing the single-crystal X-ray diffractometer facility.
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