organic compounds
H-chromene-3-carbaldehyde
of 6,7-dichloro-4-oxo-4aSchool of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
*Correspondence e-mail: ishi206@u-shizuoka-ken.ac.jp
In the title compound, C10H4Cl2O3, a dichlorinated 3-formylchromone, the non-H atoms of the 4H-chromene ring are essentially coplanar (r.m.s. = 0.0188 Å), with the largest deviation from the least-squares plane [0.043 (2) Å] being for the pyran C=O C atom. The α,β-unsaturated carbonyl O atom deviates from the least-square plane by 0.124 (2) Å. The dihedral angle between the chromone and formyl least-square planes is 6.76 (3)°. In the crystal, molecules are linked through C—H⋯O hydrogen bonds between the translation-symmetry and inversion-symmetry equivalents to form tetrads, which are further assembled by stacking interactions [centroid–centroid distance between the benzene rings = 3.769 (2) Å]. van der Waals contacts are found between the Cl atoms at the 6-position and the Cl atoms at 7-position of the glide-reflection-symmetry equivalents [Cl⋯Cl = 3.4785 (16) Å, C—Cl⋯Cl = 160.23 (7)° and Cl⋯Cl—C = 122.59 (7)°].
Keywords: crystal structure; chromone; hydrogen bonding; halogen–halogen contact; stacking interaction.
CCDC reference: 1416757
1. Related literature
For related structures, see: Ishikawa & Motohashi (2013); Ishikawa (2014a,b, 2015). For halogen bonding and halogen⋯halogen interactions, see: Auffinger et al. (2004); Metrangolo et al. (2005); Metrangolo & Resnati (2014); Mukherjee & Desiraju (2014); Wilcken et al. (2013); Sirimulla et al. (2013); Persch et al. (2015).
2. Experimental
2.1. Crystal data
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2.3. Refinement
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Data collection: WinAFC Diffractometer Control Software (Rigaku, 1999); cell WinAFC Diffractometer Control Software; data reduction: WinAFC Diffractometer Control Software; program(s) used to solve structure: SIR2011 (Burla et al., 2012); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: CrystalStructure (Rigaku, 2015); software used to prepare material for publication: CrystalStructure.
Supporting information
CCDC reference: 1416757
https://doi.org/10.1107/S2056989015014644/zl2636sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015014644/zl2636Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989015014644/zl2636Isup3.cml
To a solution of 4',5'-dichloro-2'-hydroxyacetophenone (4.8 mmol) in N,N-dimethylformamide (15 ml) was added dropwise POCl3 (12.0 mmol) at 0 °C. After the mixture was stirred for 14 h at room temperature, water (50 ml) was added. The precipitates were collected, washed with water and dried in vacuo (yield: 65%). 1H NMR (400 MHz, CDCl3): δ = 7.71 (s, 1H), 8.37 (s, 1H), 8.52 (s, 1H), 10.35 (s, 1H). Single crystals suitable for X-ray diffraction were obtained from a 1,2-dichloroethane solution of the title compound at room temperature.
The C(sp2)-bound hydrogen atoms were placed in geometrical positions [C–H 0.95 Å, Uiso(H) = 1.2Ueq(C)], and refined using a riding model. One reflection (–3 0 2) was omitted because of systematic error.
Halogen bonding is an electrostatic interaction between an electrophilic region of a halogen atom and a nucleophilic region of an atom, and has attracted much attention in medicinal chemistry, chemical biology, supramolecular chemistry and crystal engineering (Auffinger et al., 2004, Metrangolo et al., 2005, Wilcken et al., 2013, Sirimulla et al., 2013, Mukherjee & Desiraju, 2014, Metrangolo & Resnati, 2014, Persch et al., 2015). This is characterized by a short contact between the two atoms.
I have reported the crystal structures of chlorinated 3-formylchromones 6-chloro-4-oxo-4H-chromene-3-carbaldehyde (Ishikawa, 2014a), 7-chloro-4-oxo-4H-chromene-3-carbaldehyde (Ishikawa, 2014b), 6,8-dichloro-4-oxochromene-3-carbaldehyde (Ishikawa & Motohashi, 2013) and 7,8-dichloro-4-oxo-4H-chromene-3-carbaldehyde (Ishikawa, 2015). As for the monochlorinated 3-formylchromones, van der Waals contacts are observed between the formyl oxygen atom and the chlorine atom at 6-position in 6-chloro-4-oxo-4H-chromene-3-carbaldehyde (Fig. 1a), and between the chlorine atoms at 7-position in 7-chloro-4-oxo-4H-chromene-3-carbaldehyde (Fig. 1b). On the other hand, as for the dichlorinated 3-formylchromones, halogen bonds are observed between the formyl oxygen atom and the chlorine atom at 8-position in 6,8-dichloro-4-oxochromene-3-carbaldehyde (Fig. 1c), and between the formyl oxygen atom and the chlorine atom at 7-position in 7,8-dichloro-4-oxo-4H-chromene-3-carbaldehyde (Fig. 1d). As part of my investigation into these types of chemical bonding, I herein report the
of a dichlorinated 3-formylchromone 6,7-dichloro-4-oxo-4H-chromene-3-carbaldehyde. The main objective of this study is to reveal the interaction modes of the chlorine substituents of the title compound in the solid state.The mean deviation of the least-square plane for the non-hydrogen atoms of the 4H-chromene ring is 0.0188 Å, and the largest deviation is 0.043 (2) Å for the C3 atom (Fig. 2). The α,β-unsaturated carbonyl O2 atom deviates from the least-square plane by 0.124 (2) Å. The dihedral angle between the chromene least-square plane and the formyl C2–C10–O3 plane is 6.76 (3)°.
In the crystal, the molecules are linked through C–H···O hydrogen bonds between the translation-symmetryi and inversion-symmetry equivalentsii,iii to form tetrads [i: x – 1, y + 1, z, ii: –x + 1, –y, –z + 1, iii: –x + 2, –y + 1, –z + 1], which are further assembled by stacking interactions [centroid–centroid distance between the benzene rings of the 4H-chromene units = 3.769 (2) Å], as shown in Fig. 3.
Van der Waals contacts are found between the chlorine atoms at 6-position and the chlorine atoms at 7-position of the glide-reflection-symmetry equivalentsiv [Cl1···Cl2iv = 3.4785 (16) Å, C5–Cl1···Cl2iv = 160.23 (7)°, Cl1···Cl2iv–C6iv = 122.59 (7)°, iv: –x + 1, y – 1/2, –z + 1/2], as shown in Fig. 1e. Thus, short contacts are observed for the chlorine atoms in the title compound. The interaction modes of the chlorine atoms in these dichlorinated 3-formylchromones might depend on how strongly the chlorine atoms interact with the oxygen and other vicinal chlorine atoms intramolecularly. These findings could be helpful to rational drug design considering halogen bonding.
For related structures, see: Ishikawa & Motohashi (2013); Ishikawa (2014a,b, 2015). For halogen bonding, see: Auffinger et al. (2004); Metrangolo et al. (2005); Metrangolo & Resnati (2014); Mukherjee & Desiraju (2014); Wilcken et al. (2013); Sirimulla et al. (2013); Persch et al. (2015).
Data collection: WinAFC Diffractometer Control Software (Rigaku, 1999); cell
WinAFC Diffractometer Control Software (Rigaku, 1999); data reduction: WinAFC Diffractometer Control Software (Rigaku, 1999); program(s) used to solve structure: SIR2011 (Burla et al., 2012); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: CrystalStructure (Rigaku, 2015); software used to prepare material for publication: CrystalStructure (Rigaku, 2015).C10H4Cl2O3 | F(000) = 488.00 |
Mr = 243.05 | Dx = 1.767 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71069 Å |
a = 3.7695 (13) Å | Cell parameters from 25 reflections |
b = 6.1465 (16) Å | θ = 15.2–17.2° |
c = 39.431 (13) Å | µ = 0.69 mm−1 |
β = 90.72 (3)° | T = 140 K |
V = 913.5 (5) Å3 | Plate, yellow |
Z = 4 | 0.30 × 0.25 × 0.10 mm |
Rigaku AFC–7R diffractometer | Rint = 0.052 |
ω scans | θmax = 27.8°, θmin = 3.1° |
Absorption correction: ψ scan (North et al., 1968) | h = −4→2 |
Tmin = 0.574, Tmax = 0.934 | k = −7→7 |
5075 measured reflections | l = −50→50 |
2089 independent reflections | 3 standard reflections every 150 reflections |
1747 reflections with F2 > 2.0σ(F2) | intensity decay: 0.6% |
Refinement on F2 | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.034 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.098 | H-atom parameters constrained |
S = 1.04 | w = 1/[σ2(Fo2) + (0.0487P)2 + 0.5553P] where P = (Fo2 + 2Fc2)/3 |
2089 reflections | (Δ/σ)max < 0.001 |
136 parameters | Δρmax = 0.29 e Å−3 |
0 restraints | Δρmin = −0.36 e Å−3 |
Primary atom site location: structure-invariant direct methods |
C10H4Cl2O3 | V = 913.5 (5) Å3 |
Mr = 243.05 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 3.7695 (13) Å | µ = 0.69 mm−1 |
b = 6.1465 (16) Å | T = 140 K |
c = 39.431 (13) Å | 0.30 × 0.25 × 0.10 mm |
β = 90.72 (3)° |
Rigaku AFC–7R diffractometer | 1747 reflections with F2 > 2.0σ(F2) |
Absorption correction: ψ scan (North et al., 1968) | Rint = 0.052 |
Tmin = 0.574, Tmax = 0.934 | 3 standard reflections every 150 reflections |
5075 measured reflections | intensity decay: 0.6% |
2089 independent reflections |
R[F2 > 2σ(F2)] = 0.034 | 0 restraints |
wR(F2) = 0.098 | H-atom parameters constrained |
S = 1.04 | Δρmax = 0.29 e Å−3 |
2089 reflections | Δρmin = −0.36 e Å−3 |
136 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 was performed using all reflections. The weighted R-factor (wR) and goodness of fit (S) are based on F2. R-factor (gt) are based on F. The threshold expression of F2 > 2.0 σ(F2) is used only for calculating R-factor (gt). |
x | y | z | Uiso*/Ueq | ||
Cl1 | 0.55004 (14) | 0.47912 (8) | 0.27821 (2) | 0.02586 (15) | |
Cl2 | 0.92228 (14) | 0.92474 (8) | 0.29767 (2) | 0.02698 (15) | |
O1 | 0.8830 (4) | 0.6908 (2) | 0.41933 (3) | 0.0230 (3) | |
O2 | 0.3678 (4) | 0.1171 (2) | 0.40111 (3) | 0.0274 (3) | |
O3 | 0.7039 (5) | 0.2474 (3) | 0.49732 (4) | 0.0373 (4) | |
C1 | 0.8118 (6) | 0.5474 (3) | 0.44408 (5) | 0.0224 (4) | |
H1 | 0.8796 | 0.5864 | 0.4666 | 0.027* | |
C2 | 0.6523 (5) | 0.3530 (3) | 0.43968 (4) | 0.0208 (4) | |
C3 | 0.5328 (5) | 0.2856 (3) | 0.40621 (5) | 0.0199 (4) | |
C4 | 0.5555 (5) | 0.3935 (3) | 0.34486 (4) | 0.0192 (4) | |
H2 | 0.4430 | 0.2604 | 0.3389 | 0.023* | |
C5 | 0.6442 (5) | 0.5401 (3) | 0.31980 (5) | 0.0197 (4) | |
C6 | 0.8083 (5) | 0.7381 (3) | 0.32843 (4) | 0.0189 (4) | |
C7 | 0.8846 (5) | 0.7862 (3) | 0.36175 (5) | 0.0199 (4) | |
H3 | 0.9962 | 0.9196 | 0.3678 | 0.024* | |
C8 | 0.6295 (5) | 0.4389 (3) | 0.37891 (4) | 0.0180 (4) | |
C9 | 0.7948 (5) | 0.6354 (3) | 0.38648 (4) | 0.0188 (4) | |
C10 | 0.5952 (6) | 0.2085 (3) | 0.46908 (5) | 0.0278 (5) | |
H4 | 0.4657 | 0.0777 | 0.4655 | 0.033* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0352 (3) | 0.0278 (3) | 0.0144 (2) | −0.0004 (2) | −0.00603 (19) | −0.00328 (17) |
Cl2 | 0.0343 (3) | 0.0257 (3) | 0.0209 (2) | −0.0016 (2) | −0.0012 (2) | 0.00378 (18) |
O1 | 0.0335 (8) | 0.0206 (7) | 0.0148 (6) | −0.0087 (6) | −0.0050 (5) | −0.0014 (5) |
O2 | 0.0360 (9) | 0.0226 (7) | 0.0234 (7) | −0.0121 (6) | −0.0061 (6) | −0.0005 (6) |
O3 | 0.0558 (11) | 0.0357 (9) | 0.0200 (7) | −0.0143 (8) | −0.0102 (7) | 0.0052 (6) |
C1 | 0.0285 (11) | 0.0233 (9) | 0.0153 (8) | −0.0030 (8) | −0.0021 (7) | −0.0011 (7) |
C2 | 0.0253 (10) | 0.0205 (9) | 0.0166 (9) | −0.0041 (8) | −0.0024 (7) | −0.0002 (7) |
C3 | 0.0229 (10) | 0.0192 (9) | 0.0175 (9) | −0.0013 (7) | −0.0018 (7) | −0.0019 (7) |
C4 | 0.0224 (10) | 0.0177 (8) | 0.0174 (8) | −0.0008 (7) | −0.0033 (7) | −0.0037 (7) |
C5 | 0.0223 (9) | 0.0217 (9) | 0.0149 (8) | 0.0018 (7) | −0.0029 (7) | −0.0034 (7) |
C6 | 0.0219 (10) | 0.0186 (9) | 0.0161 (8) | 0.0004 (7) | −0.0016 (7) | 0.0021 (7) |
C7 | 0.0222 (10) | 0.0175 (8) | 0.0197 (9) | −0.0029 (7) | −0.0023 (7) | −0.0020 (7) |
C8 | 0.0209 (9) | 0.0170 (8) | 0.0161 (8) | −0.0013 (7) | −0.0029 (7) | −0.0017 (6) |
C9 | 0.0225 (9) | 0.0193 (8) | 0.0146 (8) | −0.0012 (7) | −0.0035 (7) | −0.0034 (7) |
C10 | 0.0370 (12) | 0.0265 (10) | 0.0199 (9) | −0.0081 (9) | −0.0032 (8) | 0.0023 (8) |
Cl1—C5 | 1.7148 (19) | C3—C8 | 1.480 (3) |
Cl2—C6 | 1.7275 (19) | C4—C5 | 1.381 (3) |
O1—C1 | 1.344 (2) | C4—C8 | 1.396 (2) |
O1—C9 | 1.376 (2) | C4—H2 | 0.9500 |
O2—C3 | 1.223 (2) | C5—C6 | 1.405 (3) |
O3—C10 | 1.206 (2) | C6—C7 | 1.374 (2) |
C1—C2 | 1.348 (3) | C7—C9 | 1.391 (3) |
C1—H1 | 0.9500 | C7—H3 | 0.9500 |
C2—C3 | 1.450 (2) | C8—C9 | 1.390 (3) |
C2—C10 | 1.478 (3) | C10—H4 | 0.9500 |
C1—O1—C9 | 118.23 (15) | C7—C6—C5 | 120.28 (17) |
O1—C1—C2 | 125.47 (16) | C7—C6—Cl2 | 118.54 (15) |
O1—C1—H1 | 117.3 | C5—C6—Cl2 | 121.18 (14) |
C2—C1—H1 | 117.3 | C6—C7—C9 | 118.52 (17) |
C1—C2—C3 | 120.25 (17) | C6—C7—H3 | 120.7 |
C1—C2—C10 | 120.05 (17) | C9—C7—H3 | 120.7 |
C3—C2—C10 | 119.69 (17) | C9—C8—C4 | 117.65 (17) |
O2—C3—C2 | 122.92 (17) | C9—C8—C3 | 120.72 (16) |
O2—C3—C8 | 123.27 (16) | C4—C8—C3 | 121.63 (16) |
C2—C3—C8 | 113.81 (16) | O1—C9—C8 | 121.32 (16) |
C5—C4—C8 | 120.70 (17) | O1—C9—C7 | 115.91 (16) |
C5—C4—H2 | 119.7 | C8—C9—C7 | 122.76 (16) |
C8—C4—H2 | 119.7 | O3—C10—C2 | 123.64 (19) |
C4—C5—C6 | 120.10 (16) | O3—C10—H4 | 118.2 |
C4—C5—Cl1 | 119.51 (14) | C2—C10—H4 | 118.2 |
C6—C5—Cl1 | 120.40 (15) | ||
C9—O1—C1—C2 | −1.5 (3) | C5—C4—C8—C3 | 179.21 (18) |
O1—C1—C2—C3 | −1.7 (3) | O2—C3—C8—C9 | 175.37 (19) |
O1—C1—C2—C10 | 178.9 (2) | C2—C3—C8—C9 | −4.8 (3) |
C1—C2—C3—O2 | −175.48 (19) | O2—C3—C8—C4 | −3.9 (3) |
C10—C2—C3—O2 | 3.9 (3) | C2—C3—C8—C4 | 175.93 (17) |
C1—C2—C3—C8 | 4.7 (3) | C1—O1—C9—C8 | 1.4 (3) |
C10—C2—C3—C8 | −175.96 (18) | C1—O1—C9—C7 | −177.98 (17) |
C8—C4—C5—C6 | −0.5 (3) | C4—C8—C9—O1 | −178.76 (17) |
C8—C4—C5—Cl1 | 179.93 (15) | C3—C8—C9—O1 | 1.9 (3) |
C4—C5—C6—C7 | 0.6 (3) | C4—C8—C9—C7 | 0.6 (3) |
Cl1—C5—C6—C7 | −179.76 (15) | C3—C8—C9—C7 | −178.76 (18) |
C4—C5—C6—Cl2 | −179.99 (15) | C6—C7—C9—O1 | 178.95 (17) |
Cl1—C5—C6—Cl2 | −0.4 (2) | C6—C7—C9—C8 | −0.4 (3) |
C5—C6—C7—C9 | −0.2 (3) | C1—C2—C10—O3 | −4.9 (4) |
Cl2—C6—C7—C9 | −179.59 (15) | C3—C2—C10—O3 | 175.8 (2) |
C5—C4—C8—C9 | −0.1 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
C1—H1···O3i | 0.95 | 2.34 | 3.187 (3) | 148 (1) |
C7—H3···O2ii | 0.95 | 2.26 | 3.129 (2) | 151 (1) |
Symmetry codes: (i) −x+2, −y+1, −z+1; (ii) x+1, y+1, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
C1—H1···O3i | 0.95 | 2.341 | 3.187 (3) | 148.01 (13) |
C7—H3···O2ii | 0.95 | 2.263 | 3.129 (2) | 151.30 (12) |
Symmetry codes: (i) −x+2, −y+1, −z+1; (ii) x+1, y+1, z. |
Acknowledgements
The University of Shizuoka is acknowledged for instrumentational support.
References
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This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
Halogen bonding is an electrostatic interaction between an electrophilic region of a halogen atom and a nucleophilic region of an atom, and has attracted much attention in medicinal chemistry, chemical biology, supramolecular chemistry and crystal engineering (Auffinger et al., 2004, Metrangolo et al., 2005, Wilcken et al., 2013, Sirimulla et al., 2013, Mukherjee & Desiraju, 2014, Metrangolo & Resnati, 2014, Persch et al., 2015). This is characterized by a short contact between the two atoms.
I have reported the crystal structures of chlorinated 3-formylchromones 6-chloro-4-oxo-4H-chromene-3-carbaldehyde (Ishikawa, 2014a), 7-chloro-4-oxo-4H-chromene-3-carbaldehyde (Ishikawa, 2014b), 6,8-dichloro-4-oxochromene-3-carbaldehyde (Ishikawa & Motohashi, 2013) and 7,8-dichloro-4-oxo-4H-chromene-3-carbaldehyde (Ishikawa, 2015). As for the monochlorinated 3-formylchromones, van der Waals contacts are observed between the formyl oxygen atom and the chlorine atom at 6-position in 6-chloro-4-oxo-4H-chromene-3-carbaldehyde (Fig. 1a), and between the chlorine atoms at 7-position in 7-chloro-4-oxo-4H-chromene-3-carbaldehyde (Fig. 1b). On the other hand, as for the dichlorinated 3-formylchromones, halogen bonds are observed between the formyl oxygen atom and the chlorine atom at 8-position in 6,8-dichloro-4-oxochromene-3-carbaldehyde (Fig. 1c), and between the formyl oxygen atom and the chlorine atom at 7-position in 7,8-dichloro-4-oxo-4H-chromene-3-carbaldehyde (Fig. 1d). As part of my investigation into these types of chemical bonding, I herein report the crystal structure of a dichlorinated 3-formylchromone 6,7-dichloro-4-oxo-4H-chromene-3-carbaldehyde. The main objective of this study is to reveal the interaction modes of the chlorine substituents of the title compound in the solid state.
The mean deviation of the least-square plane for the non-hydrogen atoms of the 4H-chromene ring is 0.0188 Å, and the largest deviation is 0.043 (2) Å for the C3 atom (Fig. 2). The α,β-unsaturated carbonyl O2 atom deviates from the least-square plane by 0.124 (2) Å. The dihedral angle between the chromene least-square plane and the formyl C2–C10–O3 plane is 6.76 (3)°.
In the crystal, the molecules are linked through C–H···O hydrogen bonds between the translation-symmetryi and inversion-symmetry equivalentsii,iii to form tetrads [i: x – 1, y + 1, z, ii: –x + 1, –y, –z + 1, iii: –x + 2, –y + 1, –z + 1], which are further assembled by stacking interactions [centroid–centroid distance between the benzene rings of the 4H-chromene units = 3.769 (2) Å], as shown in Fig. 3.
Van der Waals contacts are found between the chlorine atoms at 6-position and the chlorine atoms at 7-position of the glide-reflection-symmetry equivalentsiv [Cl1···Cl2iv = 3.4785 (16) Å, C5–Cl1···Cl2iv = 160.23 (7)°, Cl1···Cl2iv–C6iv = 122.59 (7)°, iv: –x + 1, y – 1/2, –z + 1/2], as shown in Fig. 1e. Thus, short contacts are observed for the chlorine atoms in the title compound. The interaction modes of the chlorine atoms in these dichlorinated 3-formylchromones might depend on how strongly the chlorine atoms interact with the oxygen and other vicinal chlorine atoms intramolecularly. These findings could be helpful to rational drug design considering halogen bonding.