supplementary materials


hg5252 scheme

Acta Cryst. (2012). E68, o3062    [ doi:10.1107/S1600536812040561 ]

3-(3,4-Dichlorobenzylidene)chroman-4-one

K. Gopaul, N. A. Koorbanally, M. M. Shaikh, H. Su and D. Ramjugernath

Abstract top

The distinctive feature of the structure of the title compound, C16H10Cl2O2, is the formation of a zigzag chain along [100] via Cl...Cl interactions [3.591 (1) and 3.631 (1) Å]. The chromanone moiety is fused with the benzene ring and adopts a half-chair conformation. The dihedral angle between the benzene ring of the chromanone moiety and the dichlorobenzene plane is 56.14 (8)°.

Comment top

The title compound, 3-(3,4-dichlorobenzylidene)chroman-4-one (C16H10Cl2O2), belongs to a class of compounds called homoisoflavonoids, which are C-16, α,β unsaturated carbonyl compounds containing two aromatic rings. They are a group of naturally occurring molecules that are structurally related to isoflavonoids but differ by containing one more carbon atom (Kirkiacharian et al., 1984; Gopaul et al., 2012).

A view of the the title compound is shown in Fig. 1. The chromanone moiety is fused with the benzene ring and adopts a half chair conformation. The dihedral angle between the benzene ring of the chromanone moiety and the dichlorobenzene plane is 56.14 (8)°. The inversion-related molecules are linked into zigzag chains via Cl···Cl interactions between Cl2 at (x, y, z) and Cl2 at (1 - x, 1 - y, 1 - z) and Cl2 at (-x, 1 - y, 1 - z) with distances of 3.591 (1) Å and 3.631 (1) Å respectively. Molecules related by translation along the a axis stack via double π···π interactions of the aromatic rings, with a centroid distance equal to the length of a axis. This feature is illustrated in Fig. 2.

Related literature top

For background to homoisoflavonoids, see: Kirkiacharian et al. (1984). For a related structure, see: Gopaul et al. (2012).

Experimental top

A mixture of chroman-4-one (1 g, 6.749 mmol), 3,4-dichlorobenzaldehyde (1.417 g, 8.099 mmol) and 10–15 drops of piperidine was heated at 80°C for 18 hrs. The reaction mixture was monitored for completion by thin layer chromatography. Upon completion, the reaction mixture was cooled, diluted with water and neutralized using 10% HCl. The reaction mixture was extracted with ethyl acetate (3 × 30 ml). The ethyl acetate layers were combined, washed with brine (20 ml), water (2 × 10 ml) and dried over anhydrous magnesium sulfate. The solvent was reduced and the compound purified by column chromatography using silica gel (Merck 9385, 40–63 µm particle size) with a mobile phase of 2% ethyl acetate in hexane to yield the title compound with a m.p. of 165–167 °C.

1H NMR: δ (p.p.m.): 5.27 (2H, d, J = 1.88 Hz, H-2), 6.96 (1H, d, J = 8.28 Hz, H-8), 7.07 (1H, td, J = 7.52, 0.68 Hz, H-6), 7.12 (1H, dd, J = 8.28, 1.96 Hz, H-6'), 7.38 (1H, d, J = 1.92 Hz, H-2'), 7.49 (1H, ddd, J = 8.72, 7.48, 1.72 Hz, H-7), 7.50 (1H, d, J = 8.40 Hz, H-5'), 7.72 (1H, s, H-9), 8.00 (1H, dd, J = 7.88, 1.64 Hz, H-5)

13C NMR: δ (p.p.m.): 67.27 (C-2), 118.00 (C-8), 121.79 (C-4a), 122.16 (C-6), 128.00 (C-5), 128.94 (C-6'), 130.79 (C-5'), 131.41 (C-2'), 132.44 (C-3), 133.15 (C-1'), 133.69 (C-3'), 134.28 (C-4'), 134.55 (C-9), 136.19 (C-7), 161.13 (C-8a), 181.71(C-4)

Refinement top

All hydrogen atoms were placed in geometrically idealized positions and constrainted to ride on their parent atoms, with aromatic C—H = 0.95 Å and methylene C—H = 0.99 Å; Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound, showing the atom labelling scheme and with displacement ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. Partial packing diagram showing the Cl···Cl interactions and π···π stacking as dashed lines. H atoms have been omitted.
3-(3,4-Dichlorobenzylidene)chroman-4-one top
Crystal data top
C16H10Cl2O2F(000) = 624
Mr = 305.14Dx = 1.551 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 15291 reflections
a = 3.9224 (3) Åθ = 1.9–28.3°
b = 11.5175 (10) ŵ = 0.49 mm1
c = 28.957 (3) ÅT = 173 K
β = 92.270 (2)°Block, colourless
V = 1307.12 (19) Å30.16 × 0.12 × 0.11 mm
Z = 4
Data collection top
Bruker Kappa Duo APEXII Diffractometer3258 independent reflections
Radiation source: fine-focus sealed tube2611 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.037
0.5° φ scans and ω scansθmax = 28.3°, θmin = 1.9°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1997)
h = 55
Tmin = 0.925, Tmax = 0.948k = 1515
15291 measured reflectionsl = 3838
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.034Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.089H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0416P)2 + 0.370P]
where P = (Fo2 + 2Fc2)/3
3258 reflections(Δ/σ)max = 0.001
181 parametersΔρmax = 0.30 e Å3
0 restraintsΔρmin = 0.21 e Å3
Crystal data top
C16H10Cl2O2V = 1307.12 (19) Å3
Mr = 305.14Z = 4
Monoclinic, P21/cMo Kα radiation
a = 3.9224 (3) ŵ = 0.49 mm1
b = 11.5175 (10) ÅT = 173 K
c = 28.957 (3) Å0.16 × 0.12 × 0.11 mm
β = 92.270 (2)°
Data collection top
Bruker Kappa Duo APEXII Diffractometer2611 reflections with I > 2σ(I)
Absorption correction: multi-scan
(SADABS; Sheldrick, 1997)
Rint = 0.037
Tmin = 0.925, Tmax = 0.948θmax = 28.3°
15291 measured reflectionsStandard reflections: 0
3258 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.034H-atom parameters constrained
wR(F2) = 0.089Δρmax = 0.30 e Å3
S = 1.03Δρmin = 0.21 e Å3
3258 reflectionsAbsolute structure: ?
181 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl10.42734 (11)0.87066 (4)0.446666 (14)0.03559 (12)
Cl20.24634 (12)0.61056 (4)0.471571 (14)0.04001 (13)
O10.1216 (3)0.60873 (9)0.19421 (4)0.0295 (3)
O20.4016 (3)0.91508 (10)0.20528 (4)0.0370 (3)
C10.0018 (4)0.66516 (13)0.15546 (5)0.0257 (3)
C20.0674 (4)0.62604 (13)0.23556 (5)0.0264 (3)
H2A0.06890.59620.26250.032*
H2B0.28150.58060.23300.032*
C30.1530 (4)0.75127 (12)0.24381 (5)0.0246 (3)
C40.2625 (4)0.82037 (13)0.20229 (6)0.0263 (3)
C50.1875 (4)0.76778 (13)0.15740 (5)0.0253 (3)
C60.2890 (4)0.82258 (14)0.11584 (6)0.0316 (4)
H60.41860.89220.11660.038*
C70.2037 (5)0.77697 (16)0.07401 (6)0.0374 (4)
H70.27370.81480.04610.045*
C80.0143 (5)0.67520 (16)0.07285 (6)0.0365 (4)
H80.04530.64370.04390.044*
C90.0882 (4)0.61927 (14)0.11313 (6)0.0315 (3)
H90.21740.54960.11200.038*
C100.1366 (4)0.80455 (13)0.28501 (5)0.0269 (3)
H100.19230.88480.28480.032*
C110.0434 (4)0.75431 (13)0.33026 (5)0.0253 (3)
C120.1296 (4)0.82387 (13)0.36316 (5)0.0258 (3)
H120.18650.90150.35550.031*
C130.2187 (4)0.78142 (13)0.40650 (5)0.0256 (3)
C140.1346 (4)0.66795 (14)0.41804 (5)0.0263 (3)
C150.0449 (4)0.59937 (13)0.38621 (6)0.0275 (3)
H150.10750.52260.39440.033*
C160.1336 (4)0.64150 (13)0.34272 (5)0.0261 (3)
H160.25650.59360.32120.031*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0386 (2)0.0369 (2)0.0310 (2)0.00723 (17)0.00110 (17)0.00681 (16)
Cl20.0470 (3)0.0436 (3)0.0291 (2)0.00285 (19)0.00218 (18)0.00968 (17)
O10.0354 (6)0.0268 (6)0.0265 (6)0.0085 (4)0.0024 (5)0.0026 (4)
O20.0447 (7)0.0258 (6)0.0400 (7)0.0113 (5)0.0050 (6)0.0018 (5)
C10.0265 (7)0.0234 (7)0.0269 (8)0.0051 (6)0.0014 (6)0.0021 (6)
C20.0314 (8)0.0232 (7)0.0245 (7)0.0025 (6)0.0013 (6)0.0011 (6)
C30.0226 (7)0.0227 (7)0.0283 (8)0.0016 (5)0.0007 (6)0.0020 (6)
C40.0247 (7)0.0217 (7)0.0321 (8)0.0006 (6)0.0032 (6)0.0020 (6)
C50.0236 (7)0.0240 (7)0.0279 (8)0.0047 (6)0.0030 (6)0.0034 (6)
C60.0283 (8)0.0314 (8)0.0348 (9)0.0041 (6)0.0046 (7)0.0082 (7)
C70.0363 (9)0.0467 (10)0.0286 (9)0.0110 (8)0.0049 (7)0.0108 (7)
C80.0387 (9)0.0440 (10)0.0271 (8)0.0118 (8)0.0044 (7)0.0016 (7)
C90.0332 (8)0.0298 (8)0.0317 (9)0.0066 (7)0.0052 (7)0.0013 (6)
C100.0262 (7)0.0224 (7)0.0322 (8)0.0013 (6)0.0014 (6)0.0013 (6)
C110.0264 (7)0.0232 (7)0.0265 (8)0.0030 (6)0.0044 (6)0.0008 (6)
C120.0282 (8)0.0207 (7)0.0287 (8)0.0000 (6)0.0052 (6)0.0021 (6)
C130.0242 (7)0.0266 (7)0.0261 (8)0.0008 (6)0.0030 (6)0.0038 (6)
C140.0258 (7)0.0299 (8)0.0233 (7)0.0020 (6)0.0036 (6)0.0039 (6)
C150.0274 (8)0.0224 (7)0.0330 (8)0.0016 (6)0.0058 (6)0.0021 (6)
C160.0257 (7)0.0239 (7)0.0287 (8)0.0010 (6)0.0020 (6)0.0032 (6)
Geometric parameters (Å, º) top
Cl1—C131.7330 (15)C7—C81.389 (3)
Cl2—C141.7256 (15)C7—H70.9500
O1—C11.3641 (18)C8—C91.378 (2)
O1—C21.4470 (19)C8—H80.9500
O2—C41.2243 (19)C9—H90.9500
C1—C91.389 (2)C10—C111.465 (2)
C1—C51.398 (2)C10—H100.9500
C2—C31.502 (2)C11—C161.398 (2)
C2—H2A0.9900C11—C121.400 (2)
C2—H2B0.9900C12—C131.379 (2)
C3—C101.341 (2)C12—H120.9500
C3—C41.491 (2)C13—C141.392 (2)
C4—C51.474 (2)C14—C151.385 (2)
C5—C61.402 (2)C15—C161.381 (2)
C6—C71.374 (3)C15—H150.9500
C6—H60.9500C16—H160.9500
C1—O1—C2116.35 (12)C9—C8—H8119.6
O1—C1—C9117.15 (14)C7—C8—H8119.6
O1—C1—C5122.42 (14)C8—C9—C1119.71 (16)
C9—C1—C5120.37 (15)C8—C9—H9120.1
O1—C2—C3112.89 (12)C1—C9—H9120.1
O1—C2—H2A109.0C3—C10—C11128.05 (14)
C3—C2—H2A109.0C3—C10—H10116.0
O1—C2—H2B109.0C11—C10—H10116.0
C3—C2—H2B109.0C16—C11—C12118.51 (14)
H2A—C2—H2B107.8C16—C11—C10122.76 (14)
C10—C3—C4118.39 (13)C12—C11—C10118.66 (13)
C10—C3—C2125.29 (14)C13—C12—C11121.01 (14)
C4—C3—C2116.32 (13)C13—C12—H12119.5
O2—C4—C5122.25 (14)C11—C12—H12119.5
O2—C4—C3122.24 (15)C12—C13—C14119.84 (14)
C5—C4—C3115.51 (13)C12—C13—Cl1119.77 (12)
C1—C5—C6118.63 (15)C14—C13—Cl1120.38 (12)
C1—C5—C4120.50 (13)C15—C14—C13119.66 (14)
C6—C5—C4120.79 (14)C15—C14—Cl2118.93 (12)
C7—C6—C5120.90 (16)C13—C14—Cl2121.41 (12)
C7—C6—H6119.5C16—C15—C14120.64 (14)
C5—C6—H6119.5C16—C15—H15119.7
C6—C7—C8119.56 (16)C14—C15—H15119.7
C6—C7—H7120.2C15—C16—C11120.31 (14)
C8—C7—H7120.2C15—C16—H16119.8
C9—C8—C7120.82 (16)C11—C16—H16119.8
C2—O1—C1—C9156.47 (14)C7—C8—C9—C10.1 (2)
C2—O1—C1—C526.3 (2)O1—C1—C9—C8177.45 (14)
C1—O1—C2—C346.21 (17)C5—C1—C9—C80.2 (2)
O1—C2—C3—C10138.89 (16)C4—C3—C10—C11178.67 (15)
O1—C2—C3—C440.74 (18)C2—C3—C10—C111.7 (3)
C10—C3—C4—O215.1 (2)C3—C10—C11—C1636.4 (2)
C2—C3—C4—O2165.28 (15)C3—C10—C11—C12146.59 (17)
C10—C3—C4—C5164.10 (14)C16—C11—C12—C131.9 (2)
C2—C3—C4—C515.56 (19)C10—C11—C12—C13179.04 (14)
O1—C1—C5—C6177.47 (13)C11—C12—C13—C140.4 (2)
C9—C1—C5—C60.3 (2)C11—C12—C13—Cl1179.05 (12)
O1—C1—C5—C40.7 (2)C12—C13—C14—C151.4 (2)
C9—C1—C5—C4176.41 (14)Cl1—C13—C14—C15177.26 (12)
O2—C4—C5—C1173.56 (15)C12—C13—C14—Cl2179.08 (12)
C3—C4—C5—C15.6 (2)Cl1—C13—C14—Cl22.23 (19)
O2—C4—C5—C63.1 (2)C13—C14—C15—C161.6 (2)
C3—C4—C5—C6177.72 (14)Cl2—C14—C15—C16178.85 (12)
C1—C5—C6—C70.3 (2)C14—C15—C16—C110.1 (2)
C4—C5—C6—C7176.48 (15)C12—C11—C16—C151.7 (2)
C5—C6—C7—C80.0 (2)C10—C11—C16—C15178.69 (15)
C6—C7—C8—C90.2 (3)
Acknowledgements top

We thank the University of KwaZulu-Natal and the South Africa Research Chairs initiative of the Department of Science and Technology for financial support and the National Research Foundation of South Africa for a bursary for KG.

references
References top

Bruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.

Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849–854.

Gopaul, K., Shaikh, M., Ramjugernath, D., Koorbanally, N. A. & Omondi, B. (2012). Acta Cryst. E68, o1006.

Kirkiacharian, B. S., Gomis, M., Tongo, H. G., Mahuteau, J. & Brion, J. D. (1984). Org. Magn. Reson. 22, 106–108.

Sheldrick, G. M. (1997). SADABS. University of Göttingen, Germany.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.