organic compounds
Ethyl (E)-3-(6-methyl-4-oxo-4H-chromen-3-yl)prop-2-enoate
aH.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan
*Correspondence e-mail: dr.sammer.yousuf@gmail.com
In the title compound, C15H14O4, the chromone ring system is close to being planar [maximum deviation = 0.015 (2) Å]. The double bond of the ethyl prop-2-enoate chain adopts an E conformation and an intramolecular C—H⋯O hydrogen bond generates an S6 ring. In the crystal, inversion dimers linked by pairs of C—H⋯O hydrogen bonds generate R22(14) loops. Weak π–π interactions [centroid–centroid distance = 3.8493 (12) Å] also occur.
Related literature
For the biological activity of chromones, see: Patel et al. (2011); Khan et al. (2010); Gautam et al. (2010). For a related structure, see: Wang & Kong (2007).
Experimental
Crystal data
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Refinement
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Data collection: SMART (Bruker, 2000); cell SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL and PARST (Nardelli, 1995) and PLATON (Spek, 2009).
Supporting information
https://doi.org/10.1107/S1600536812038585/hb6950sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812038585/hb6950Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S1600536812038585/hb6950Isup3.cml
A mixture of 3-formyl chromone (10 mmol) and malonic acid (20 mmol), using pyridine (15 ml) as solvent was refluxed in 500 mL round-bottomed flask for 30–45 minutes with vigorous stirring. After completion of reaction (monitored by TLC), the reaction mixture was cooled to room temperature, acidified by concntrated hydrochloric acid (pH 1.0) and stirred again for 30 minutes at room temprature. The yellow colored solid (1.02 g) obtained was filtered and washed with water. The crude residue was dried, dissolved in ethanol (50 ml) along with few drops of H2SO4 and refluxed for 24 h (progress of the reaction was monitored by TLC). After completion of reaction the solvent was evaporated under vacuum followed by addition of
of NaHCO3 and extracted with ethyl acetate, washed with water. The organic phase was dried over Na2SO4. The solvent was evaporated under reduced pressure to obtain crude product which was further recrystallized in ethanol to obtain yellow blocks in 82% yield (0.94 g).H atoms on Methyl, methylene and methine were positioned geometrically with C—H = 0.96 Å (CH3), 0.97 Å (CH3) and 0.93 Å (CH) and constrained to ride on their parent atoms with Uiso(H)= 1.5Ueq(CH3) and 1.2Ueq(CH2, CH).
Chromone is a group of naturally occurring oxygen containing π–π interaction between pyrane (Cg(1)= O1/C6–C9) and benzene (Cg(2)= C1–C6) of chromone moeity ((Cg(1)to Cg(2) distance = 3.8493 (12) Å;X,1/2-Y,-1/2+Z)
having a benzene ring fused with pyran ring. They are widely distributed in plant kingdom and form the basic nucleus of important compounds such as anthocyanin and The chromone moiety forms an important component of pharmacophores of a number of biologically active molecules of synthetic as well as natural origin and therefore responsible for various biological activities (e.g. Patel et al. (2011); Gautam et al. (2010); Khan et al. (2010). The title compound is a chromone derivative obtained as a part of our ongoing project to synthesize libraries of chromone derivatives in order to study their different biological activities. The structure of title compound (Fig. 1) is composed of almost planner chromone moiety (O1/C1–C9) with maximum deviation of 0.015 (2) Å for C7 atom from the root mean square plane. The C11–C12 (1.462 (3) Å) olefinic bond of ethyl prop-2-enoate chain (O3–O4/C10–C14) attached to chromone moiety adopt an E configuartion. The shorter bond lengths of C11–C12 = 1.462 (3) Å than the expected C–C single bond length is due to the conjugation effects of the olefinc bond (C11–C12, 1.462 (3) Å) with carbonyl carbon (O3/C12) of ethyl prop-2-enoate chain (O3–O4/C10–C14). The bond lengths and angle were found to be similar as in structurally realted compound (Wang & Kong, 2007). The E conformation of olefinic bound further stabilized by an intramolecular C11–C11A···O2 intramolecular hydrogen bond. In the crystal inversion-related molecules are consolidated by C9–C9A···O3 hydrogen bond and found stacked along the a-axis. The also features weakFor the biological activity of chromones, see: Patel et al. (2011); Khan et al. (2010); Gautam et al. (2010). For a related structure, see: Wang & Kong (2007).
Data collection: SMART (Bruker, 2000); cell
SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008, PARST (Nardelli, 1995) and PLATON (Spek, 2009).Fig. 1. The molecular structure of (I) with displacement ellipsoids drawn at 30% probability level. | |
Fig. 2. The crystal packing of the title compound I. |
C15H14O4 | F(000) = 544 |
Mr = 258.26 | Dx = 1.310 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 13.8663 (12) Å | Cell parameters from 1626 reflections |
b = 12.3512 (10) Å | θ = 3.0–23.3° |
c = 7.6947 (6) Å | µ = 0.10 mm−1 |
β = 96.390 (2)° | T = 298 K |
V = 1309.65 (19) Å3 | Block, colourless |
Z = 4 | 0.34 × 0.25 × 0.16 mm |
Bruker SMART APEX CCD diffractometer | 2431 independent reflections |
Radiation source: fine-focus sealed tube | 1650 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.027 |
ω scan | θmax = 25.5°, θmin = 2.2° |
Absorption correction: multi-scan (SADABS; Bruker, 2000) | h = −16→16 |
Tmin = 0.968, Tmax = 0.985 | k = −14→14 |
7621 measured reflections | l = −9→9 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.048 | H-atom parameters constrained |
wR(F2) = 0.142 | w = 1/[σ2(Fo2) + (0.0754P)2 + 0.0649P] where P = (Fo2 + 2Fc2)/3 |
S = 1.04 | (Δ/σ)max < 0.001 |
2431 reflections | Δρmax = 0.17 e Å−3 |
175 parameters | Δρmin = −0.15 e Å−3 |
0 restraints | Extinction correction: SHELXTL (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0028 (16) |
C15H14O4 | V = 1309.65 (19) Å3 |
Mr = 258.26 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 13.8663 (12) Å | µ = 0.10 mm−1 |
b = 12.3512 (10) Å | T = 298 K |
c = 7.6947 (6) Å | 0.34 × 0.25 × 0.16 mm |
β = 96.390 (2)° |
Bruker SMART APEX CCD diffractometer | 2431 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2000) | 1650 reflections with I > 2σ(I) |
Tmin = 0.968, Tmax = 0.985 | Rint = 0.027 |
7621 measured reflections |
R[F2 > 2σ(F2)] = 0.048 | 0 restraints |
wR(F2) = 0.142 | H-atom parameters constrained |
S = 1.04 | Δρmax = 0.17 e Å−3 |
2431 reflections | Δρmin = −0.15 e Å−3 |
175 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 | 0.74141 (9) | 0.20992 (10) | 0.17694 (19) | 0.0713 (4) | |
O2 | 0.85161 (10) | 0.49847 (11) | 0.3624 (2) | 0.0786 (5) | |
O3 | 0.51893 (10) | 0.66244 (12) | 0.0798 (2) | 0.0880 (5) | |
O4 | 0.63447 (9) | 0.77677 (10) | 0.18750 (18) | 0.0677 (4) | |
C1 | 0.83451 (14) | 0.21480 (15) | 0.2624 (3) | 0.0597 (5) | |
C2 | 0.88511 (15) | 0.11889 (17) | 0.2813 (3) | 0.0715 (6) | |
H2A | 0.8566 | 0.0542 | 0.2405 | 0.086* | |
C3 | 0.97837 (16) | 0.12068 (19) | 0.3615 (3) | 0.0731 (6) | |
H3A | 1.0133 | 0.0563 | 0.3724 | 0.088* | |
C4 | 1.02265 (14) | 0.21586 (18) | 0.4273 (3) | 0.0653 (6) | |
C5 | 0.97015 (13) | 0.31040 (17) | 0.4062 (2) | 0.0614 (5) | |
H5A | 0.9987 | 0.3749 | 0.4476 | 0.074* | |
C6 | 0.87513 (12) | 0.31198 (15) | 0.3241 (2) | 0.0540 (5) | |
C7 | 0.81876 (12) | 0.41241 (16) | 0.3029 (2) | 0.0570 (5) | |
C8 | 0.72174 (12) | 0.40105 (15) | 0.2076 (2) | 0.0537 (5) | |
C9 | 0.69141 (14) | 0.30212 (16) | 0.1524 (3) | 0.0637 (5) | |
H9A | 0.6298 | 0.2975 | 0.0913 | 0.076* | |
C10 | 0.65611 (13) | 0.49171 (15) | 0.1662 (2) | 0.0571 (5) | |
H10A | 0.5964 | 0.4750 | 0.1047 | 0.069* | |
C11 | 0.67129 (13) | 0.59483 (16) | 0.2054 (3) | 0.0594 (5) | |
H11A | 0.7292 | 0.6151 | 0.2697 | 0.071* | |
C12 | 0.59924 (13) | 0.67789 (15) | 0.1500 (3) | 0.0595 (5) | |
C13 | 0.57176 (15) | 0.86723 (17) | 0.1372 (3) | 0.0764 (6) | |
H13A | 0.5168 | 0.8677 | 0.2049 | 0.092* | |
H13B | 0.5476 | 0.8624 | 0.0142 | 0.092* | |
C14 | 0.63063 (19) | 0.96782 (18) | 0.1716 (3) | 0.0915 (8) | |
H14A | 0.5895 | 1.0300 | 0.1511 | 0.137* | |
H14B | 0.6807 | 0.9700 | 0.0950 | 0.137* | |
H14C | 0.6596 | 0.9680 | 0.2909 | 0.137* | |
C15 | 1.12484 (15) | 0.2147 (2) | 0.5173 (3) | 0.0877 (7) | |
H15A | 1.1556 | 0.2827 | 0.4985 | 0.132* | |
H15B | 1.1606 | 0.1572 | 0.4703 | 0.132* | |
H15C | 1.1234 | 0.2035 | 0.6404 | 0.132* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0564 (9) | 0.0616 (9) | 0.0918 (11) | −0.0011 (6) | −0.0101 (7) | −0.0061 (7) |
O2 | 0.0551 (8) | 0.0610 (9) | 0.1124 (12) | −0.0051 (6) | −0.0225 (8) | −0.0025 (8) |
O3 | 0.0525 (9) | 0.0756 (10) | 0.1274 (14) | −0.0032 (7) | −0.0270 (9) | 0.0082 (9) |
O4 | 0.0541 (8) | 0.0600 (9) | 0.0857 (10) | 0.0022 (6) | −0.0068 (7) | 0.0026 (7) |
C1 | 0.0510 (11) | 0.0680 (13) | 0.0589 (12) | 0.0022 (9) | 0.0009 (9) | 0.0014 (10) |
C2 | 0.0715 (14) | 0.0655 (13) | 0.0760 (14) | 0.0070 (10) | 0.0019 (11) | −0.0045 (11) |
C3 | 0.0705 (14) | 0.0801 (15) | 0.0680 (14) | 0.0231 (11) | 0.0049 (11) | 0.0014 (11) |
C4 | 0.0547 (12) | 0.0860 (15) | 0.0544 (12) | 0.0135 (10) | 0.0027 (9) | −0.0025 (10) |
C5 | 0.0481 (11) | 0.0766 (14) | 0.0585 (12) | 0.0038 (9) | 0.0016 (9) | −0.0031 (10) |
C6 | 0.0450 (10) | 0.0643 (12) | 0.0521 (11) | 0.0008 (8) | 0.0023 (8) | 0.0018 (9) |
C7 | 0.0440 (10) | 0.0626 (12) | 0.0628 (12) | −0.0046 (9) | −0.0012 (9) | 0.0042 (10) |
C8 | 0.0434 (10) | 0.0589 (11) | 0.0573 (11) | −0.0043 (8) | −0.0004 (8) | 0.0041 (9) |
C9 | 0.0471 (11) | 0.0678 (13) | 0.0732 (14) | −0.0010 (9) | −0.0067 (10) | 0.0017 (10) |
C10 | 0.0416 (10) | 0.0668 (13) | 0.0611 (12) | −0.0055 (8) | −0.0028 (8) | 0.0088 (9) |
C11 | 0.0452 (10) | 0.0651 (13) | 0.0651 (12) | −0.0041 (9) | −0.0057 (9) | 0.0069 (10) |
C12 | 0.0444 (11) | 0.0650 (13) | 0.0669 (13) | −0.0038 (9) | −0.0036 (9) | 0.0065 (10) |
C13 | 0.0689 (14) | 0.0685 (14) | 0.0901 (16) | 0.0141 (10) | 0.0014 (12) | 0.0090 (11) |
C14 | 0.117 (2) | 0.0648 (14) | 0.0893 (17) | 0.0040 (13) | −0.0039 (15) | −0.0030 (12) |
C15 | 0.0587 (13) | 0.118 (2) | 0.0827 (16) | 0.0251 (13) | −0.0066 (11) | −0.0078 (14) |
O1—C9 | 1.336 (2) | C7—C8 | 1.465 (2) |
O1—C1 | 1.383 (2) | C8—C9 | 1.346 (3) |
O2—C7 | 1.225 (2) | C8—C10 | 1.456 (2) |
O3—C12 | 1.198 (2) | C9—H9A | 0.9300 |
O4—C12 | 1.335 (2) | C10—C11 | 1.320 (3) |
O4—C13 | 1.442 (2) | C10—H10A | 0.9300 |
C1—C2 | 1.376 (3) | C11—C12 | 1.462 (3) |
C1—C6 | 1.387 (3) | C11—H11A | 0.9300 |
C2—C3 | 1.370 (3) | C13—C14 | 1.494 (3) |
C2—H2A | 0.9300 | C13—H13A | 0.9700 |
C3—C4 | 1.395 (3) | C13—H13B | 0.9700 |
C3—H3A | 0.9300 | C14—H14A | 0.9600 |
C4—C5 | 1.376 (3) | C14—H14B | 0.9600 |
C4—C15 | 1.506 (3) | C14—H14C | 0.9600 |
C5—C6 | 1.396 (3) | C15—H15A | 0.9600 |
C5—H5A | 0.9300 | C15—H15B | 0.9600 |
C6—C7 | 1.466 (3) | C15—H15C | 0.9600 |
C9—O1—C1 | 118.19 (15) | C8—C9—H9A | 116.9 |
C12—O4—C13 | 117.10 (15) | C11—C10—C8 | 127.74 (18) |
C2—C1—O1 | 116.79 (18) | C11—C10—H10A | 116.1 |
C2—C1—C6 | 121.72 (19) | C8—C10—H10A | 116.1 |
O1—C1—C6 | 121.49 (16) | C10—C11—C12 | 121.59 (18) |
C3—C2—C1 | 118.6 (2) | C10—C11—H11A | 119.2 |
C3—C2—H2A | 120.7 | C12—C11—H11A | 119.2 |
C1—C2—H2A | 120.7 | O3—C12—O4 | 122.87 (18) |
C2—C3—C4 | 122.18 (19) | O3—C12—C11 | 126.20 (18) |
C2—C3—H3A | 118.9 | O4—C12—C11 | 110.92 (16) |
C4—C3—H3A | 118.9 | O4—C13—C14 | 107.19 (18) |
C5—C4—C3 | 117.80 (19) | O4—C13—H13A | 110.3 |
C5—C4—C15 | 121.4 (2) | C14—C13—H13A | 110.3 |
C3—C4—C15 | 120.81 (19) | O4—C13—H13B | 110.3 |
C4—C5—C6 | 121.70 (19) | C14—C13—H13B | 110.3 |
C4—C5—H5A | 119.1 | H13A—C13—H13B | 108.5 |
C6—C5—H5A | 119.1 | C13—C14—H14A | 109.5 |
C1—C6—C5 | 118.00 (17) | C13—C14—H14B | 109.5 |
C1—C6—C7 | 120.19 (17) | H14A—C14—H14B | 109.5 |
C5—C6—C7 | 121.81 (17) | C13—C14—H14C | 109.5 |
O2—C7—C8 | 123.54 (17) | H14A—C14—H14C | 109.5 |
O2—C7—C6 | 121.42 (16) | H14B—C14—H14C | 109.5 |
C8—C7—C6 | 115.04 (17) | C4—C15—H15A | 109.5 |
C9—C8—C10 | 117.61 (16) | C4—C15—H15B | 109.5 |
C9—C8—C7 | 118.83 (17) | H15A—C15—H15B | 109.5 |
C10—C8—C7 | 123.55 (16) | C4—C15—H15C | 109.5 |
O1—C9—C8 | 126.19 (18) | H15A—C15—H15C | 109.5 |
O1—C9—H9A | 116.9 | H15B—C15—H15C | 109.5 |
C9—O1—C1—C2 | −178.25 (17) | C1—C6—C7—C8 | −2.5 (3) |
C9—O1—C1—C6 | 1.1 (3) | C5—C6—C7—C8 | 177.57 (16) |
O1—C1—C2—C3 | 178.48 (17) | O2—C7—C8—C9 | −177.91 (19) |
C6—C1—C2—C3 | −0.8 (3) | C6—C7—C8—C9 | 1.7 (2) |
C1—C2—C3—C4 | 1.3 (3) | O2—C7—C8—C10 | 3.2 (3) |
C2—C3—C4—C5 | −1.4 (3) | C6—C7—C8—C10 | −177.23 (16) |
C2—C3—C4—C15 | 179.04 (19) | C1—O1—C9—C8 | −2.1 (3) |
C3—C4—C5—C6 | 0.9 (3) | C10—C8—C9—O1 | 179.58 (17) |
C15—C4—C5—C6 | −179.49 (19) | C7—C8—C9—O1 | 0.6 (3) |
C2—C1—C6—C5 | 0.4 (3) | C9—C8—C10—C11 | −179.17 (19) |
O1—C1—C6—C5 | −178.87 (16) | C7—C8—C10—C11 | −0.2 (3) |
C2—C1—C6—C7 | −179.49 (17) | C8—C10—C11—C12 | 178.09 (17) |
O1—C1—C6—C7 | 1.2 (3) | C13—O4—C12—O3 | −1.0 (3) |
C4—C5—C6—C1 | −0.5 (3) | C13—O4—C12—C11 | 178.89 (16) |
C4—C5—C6—C7 | 179.43 (17) | C10—C11—C12—O3 | 6.7 (3) |
C1—C6—C7—O2 | 177.08 (18) | C10—C11—C12—O4 | −173.18 (17) |
C5—C6—C7—O2 | −2.8 (3) | C12—O4—C13—C14 | −172.99 (17) |
D—H···A | D—H | H···A | D···A | D—H···A |
C11—H11A···O2 | 0.93 | 2.28 | 2.908 (2) | 124 |
C9—H9A···O3i | 0.93 | 2.37 | 3.276 (3) | 164 |
Symmetry code: (i) −x+1, −y+1, −z. |
Experimental details
Crystal data | |
Chemical formula | C15H14O4 |
Mr | 258.26 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 298 |
a, b, c (Å) | 13.8663 (12), 12.3512 (10), 7.6947 (6) |
β (°) | 96.390 (2) |
V (Å3) | 1309.65 (19) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.34 × 0.25 × 0.16 |
Data collection | |
Diffractometer | Bruker SMART APEX CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2000) |
Tmin, Tmax | 0.968, 0.985 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7621, 2431, 1650 |
Rint | 0.027 |
(sin θ/λ)max (Å−1) | 0.606 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.048, 0.142, 1.04 |
No. of reflections | 2431 |
No. of parameters | 175 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.17, −0.15 |
Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), SHELXTL (Sheldrick, 2008, PARST (Nardelli, 1995) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
C11—H11A···O2 | 0.93 | 2.28 | 2.908 (2) | 124 |
C9—H9A···O3i | 0.93 | 2.37 | 3.276 (3) | 164 |
Symmetry code: (i) −x+1, −y+1, −z. |
Acknowledgements
The authors are thankful to OPCW, Netherlands, and the Higher Education Commission (HEC) Pakistan (project No. 1910) for their financial support.
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Wang, X.-B. & Kong, L.-Y. (2007). Acta Cryst. E63, o4340. Web of Science CSD CrossRef IUCr Journals Google Scholar
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Chromone is a group of naturally occurring oxygen containing heterocyclic compounds having a benzene ring fused with pyran ring. They are widely distributed in plant kingdom and form the basic nucleus of important compounds such as anthocyanin and flavonoids. The chromone moiety forms an important component of pharmacophores of a number of biologically active molecules of synthetic as well as natural origin and therefore responsible for various biological activities (e.g. Patel et al. (2011); Gautam et al. (2010); Khan et al. (2010). The title compound is a chromone derivative obtained as a part of our ongoing project to synthesize libraries of chromone derivatives in order to study their different biological activities. The structure of title compound (Fig. 1) is composed of almost planner chromone moiety (O1/C1–C9) with maximum deviation of 0.015 (2) Å for C7 atom from the root mean square plane. The C11–C12 (1.462 (3) Å) olefinic bond of ethyl prop-2-enoate chain (O3–O4/C10–C14) attached to chromone moiety adopt an E configuartion. The shorter bond lengths of C11–C12 = 1.462 (3) Å than the expected C–C single bond length is due to the conjugation effects of the olefinc bond (C11–C12, 1.462 (3) Å) with carbonyl carbon (O3/C12) of ethyl prop-2-enoate chain (O3–O4/C10–C14). The bond lengths and angle were found to be similar as in structurally realted compound (Wang & Kong, 2007). The E conformation of olefinic bound further stabilized by an intramolecular C11–C11A···O2 intramolecular hydrogen bond. In the crystal inversion-related molecules are consolidated by C9–C9A···O3 hydrogen bond and found stacked along the a-axis. The crystal structure also features weak π–π interaction between pyrane (Cg(1)= O1/C6–C9) and benzene (Cg(2)= C1–C6) of chromone moeity ((Cg(1)to Cg(2) distance = 3.8493 (12) Å;X,1/2-Y,-1/2+Z)