6-Chloro-4-oxo-4H-chromene-3-carb­aldehyde

Yoshinobu Ishikawa

doi:10.1107/S1600536814007119

. 2014 Apr 5;70(Pt 5):o514. doi: 10.1107/S1600536814007119

6-Chloro-4-oxo-4H-chromene-3-carbaldehyde

Yoshinobu Ishikawa ^a,^*

PMCID: PMC4011265 PMID: 24860329

Abstract

In the title compound, C₁₀H₅ClO₃, a chlorinated 3-formylchromone derivative, the non-H atoms are essentially coplanar (r.m.s. deviation = 0.0456 Å) with the largest deviation from the least-squares plane [0.1136 (16) Å] being found for the ring-bound carbonyl O atom. In the crystal, molecules are linked through stacking interactions along the b axis [shortest centroid–centroid distance between the pyran and benzene rings = 3.4959 (15) Å].

Related literature

For related structures, see: Ishikawa & Motohashi (2013 ▶); Ishikawa (2014 ▶). For van der Waals radii; see: Bondi (1964 ▶). For halogen bonding, see: Auffinger et al. (2004 ▶); Metrangolo et al. (2005 ▶); Sirimulla et al. (2013 ▶).

Experimental

Crystal data

C₁₀H₅ClO₃
M _r = 208.60
Triclinic,
a = 6.5838 (16) Å
b = 6.9579 (17) Å
c = 10.265 (3) Å
α = 71.22 (3)°
β = 85.64 (2)°
γ = 69.29 (3)°
V = 416.0 (2) Å³
Z = 2
Mo Kα radiation
μ = 0.43 mm⁻¹
T = 100 K
0.36 × 0.25 × 0.12 mm

Data collection

Rigaku AFC-7R diffractometer
Absorption correction: ψ scan (North et al., 1968 ▶) T _min = 0.891, T _max = 0.950
2356 measured reflections
1906 independent reflections
1741 reflections with F ² > 2σ(F ²)
R _int = 0.058
3 standard reflections every 150 reflections intensity decay: −0.9%

Refinement

R[F ² > 2σ(F ²)] = 0.040
wR(F ²) = 0.109
S = 1.10
1906 reflections
127 parameters
H-atom parameters constrained
Δρ_max = 0.29 e Å⁻³
Δρ_min = −0.64 e Å⁻³

Data collection: WinAFC Diffractometer Control Software (Rigaku, 1999 ▶); cell refinement: WinAFC Diffractometer Control Software; data reduction: WinAFC Diffractometer Control Software; program(s) used to solve structure: SIR88 (Burla et al., 1989 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: CrystalStructure (Rigaku, 2010 ▶); software used to prepare material for publication: CrystalStructure.

Supplementary Material

Crystal structure: contains datablock(s) General, I. DOI: 10.1107/S1600536814007119/tk5303sup1.cif

e-70-0o514-sup1.cif^{(23.2KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536814007119/tk5303Isup2.hkl

e-70-0o514-Isup2.hkl^{(93.8KB, hkl)}

Click here for additional data file.^{(3.3KB, cml)}

Supporting information file. DOI: 10.1107/S1600536814007119/tk5303Isup3.cml

CCDC reference: 994454

Additional supporting information: crystallographic information; 3D view; checkCIF report

Acknowledgments

The author acknowledges the University of Shizuoka for instrumental support.

supplementary crystallographic information

1. Structural commentary

Halogen bonds have been found to occur in organic, inorganic and biological systems, and have recently attracted much attention in medicinal chemistry, chemical biology and supramolecular chemistry (Auffinger et al., 2004; Metrangolo et al., 2005; Sirimulla et al., 2013). We have recently reported the crystal structures of dihalogenated 3-formylchromone derivatives 6,8-dichloro-4-oxochromene-3-carbaldehyde (Ishikawa & Motohashi, 2013; Fig. 2 (top)) and 6,8-dibromo-4-oxochromene-3-carbaldehyde (Ishikawa, 2014). It was found that similar halogen bonds between the formyl oxygen atom and the halogen atoms at the 8-position are formed in those crystal structures. As part of our interest in this type of chemical bonding, we herein report the crystal structure of a monochlorinated 3-formylchromone derivative, 6-chloro-4-oxo-4H-chromene-3-carbaldehyde. The objective of this study is to reveal whether halogen bond(s) can be formed in the crystal structure of this compound without halogen atom at 8-position.

The mean deviation of the least-square planes for the non-hydrogen atoms is 0.0456 Å, and the largest deviations is 0.1136 (16) Å for O2. These mean that these atoms are essentially coplanar.

In the crystal, the molecules are stacked with the inversion-symmetry equivalents along the b-axis direction [centroid–centroid distance between the pyran rings of the 4H-chromene units = 3.926 (2) Å, i: -x + 2, -y + 1, -z + 1], as shown in Fig. 1. The distance between the chloride atom and the formyl oxygen atom of the translation-symmetry equivalent [Cl1···O3ⁱⁱ = 3.284 (2) Å, ii: x + 1, y, z - 1] is approximately equal to the sum of their van der Waals radii [3.27 Å] (Bondi, 1964), as shown in the middle of Fig. 2. Thus, it is concluded that there is no halogen bond in the title compound. The C–Cl···O and Cl···O=C angles are 166.30 (8) and 166.69 (14)°, respectively. The latter angle is greater than that of 6,8-dichloro-4-oxochromene-3-carbaldehyde (Ishikawa & Motohashi, 2013). A structure with halogen bonds can be modeled for the title compound (Fig.2, bottom), but it is not observed in the crystal. These results might be invaluable for the development of state-of-the-art force fields.

2. Synthesis and crystallization

Single crystals suitable for X-ray diffraction were obtained by slow evaporation of an ethyl acetate solution of the commercially available title compound at room temperature.

3. Refinement

The C(sp²)-bound hydrogen atoms were placed in geometrical positions [C–H 0.95 Å, U_iso(H) = 1.2U_eq(C)], and refined using a riding model. One reflection (1 8 2) was omitted because of systematic error.