8-Fluoro-4-oxo-4H-chromene-3-carbalde­hyde

Yoshinobu Ishikawa

doi:10.1107/S1600536814013208

. 2014 Jun 14;70(Pt 7):o774. doi: 10.1107/S1600536814013208

8-Fluoro-4-oxo-4H-chromene-3-carbaldehyde

Yoshinobu Ishikawa ^a,^*

PMCID: PMC4120633 PMID: 25161562

Abstract

In the title compound, C₁₀H₅FO₃, the non-H atoms of the 8-fluorochromone unit are essentially coplanar (r.m.s. deviation = 0.0259 Å), with a largest deviation from the mean plane of 0.0660 (12) Å for the chromone carbonyl O atom. The formyl group is twisted with respect to the attached ring [C—C—C—O torsion angles = −11.00 (19) and 170.81 (11)°]. In the crystal, molecules are linked via weak C—H⋯O hydrogen bonds along the a axis and [-101], forming corrugated layers parallel to (010). In addition, π–π stacking interactions [centroid–centroid distance between the planes of the pyran and benzene rings = 3.519 (2) Å] are observed between these layers.

Related literature

For related structures, see: Ishikawa & Motohashi (2013 ▶); Ishikawa (2014 ▶). For the synthesis of the precursor of the title compound, see: Valoti et al. (2001 ▶). For halogen bonding, see: Auffinger et al. (2004 ▶); Metrangolo et al. (2005 ▶); Wilcken et al. (2013 ▶); Sirimulla et al. (2013 ▶). graphic file with name e-70-0o774-scheme1.jpg

Experimental

Crystal data

C₁₀H₅FO₃
M _r = 192.15
Monoclinic,
a = 6.6643 (12) Å
b = 8.395 (5) Å
c = 14.247 (4) Å
β = 97.865 (16)°
V = 789.6 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.14 mm⁻¹
T = 100 K
0.40 × 0.40 × 0.20 mm

Data collection

Rigaku AFC-7R diffractometer
2445 measured reflections
1810 independent reflections
1606 reflections with F ² > 2σ(F ²)
R _int = 0.049
3 standard reflections every 150 reflections intensity decay: −0.4%

Refinement

R[F ² > 2σ(F ²)] = 0.038
wR(F ²) = 0.109
S = 1.07
1810 reflections
127 parameters
H-atom parameters constrained
Δρ_max = 0.28 e Å⁻³
Δρ_min = −0.36 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: SIR2008 (Burla, et al., 2007 ▶); 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/S1600536814013208/lh5713sup1.cif

e-70-0o774-sup1.cif^{(24.1KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536814013208/lh5713Isup2.hkl

e-70-0o774-Isup2.hkl^{(89.2KB, hkl)}

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

Supporting information file. DOI: 10.1107/S1600536814013208/lh5713Isup3.cml

CCDC reference: 1007014

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

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1ⁱ—H1ⁱ⋯O2	0.95	2.48	3.285 (2)	142 (1)
C6ⁱⁱ—H4ⁱⁱ⋯O2	0.95	2.41	3.221 (2)	143 (1)

Open in a new tab

Symmetry codes: (i) Inline graphic ; (ii) .

Acknowledgments

The University of Shizuoka is acknowledged for instrumental support.

supplementary crystallographic information

S1. Comment

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, Wilcken et al., 2013, Sirimulla et al., 2013). We have recently reported the crystal structures of a dichlorinated 3-formylchromone derivative 6,8-dichloro-4-oxochromene-3-carbaldehyde (Ishikawa & Motohashi, 2013, Fig. 3 (top)) and a monochlorinated one 8-chloro-4-oxo-4H-chromene-3-carbaldehyde (Ishikawa, 2014, Fig. 3 (bottom left)). It was found that halogen bonding is observed for 6,8-dichloro-4-oxochromene-3-carbaldehyde between the formyl oxygen atom and the chlorine atom at 8-position, but is not observed for 8-chloro-4-oxo-4H-chromene-3-carbaldehyde between the formyl oxygen atom and the chlorine atom at 8-position. As part of our interest in this type of chemical bonding, we herein report the crystal structure of a monofluorinated 3-formylchromone derivative 8-fluoro-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 with the fluorine atom at 8-position.

The mean deviation of the least-square planes for the non-hydrogen atoms of the 8-fluorochromone unit is 0.0259 Å, and the largest deviations is 0.0660 (12) Å for O2 (Fig. 1). These mean that these atoms are essentially coplanar. The formyl group is twisted [C1–C2–C10–O3 = -11.00 (19)° and C3–C2–C10–O3 = 170.81 (11)°]. In the crystal, the molecules are linked via C–H···O hydrogen bonds along the a axis and (1,0,1) to form corrugated layers parallel to (010) and viaπ–π stacking interaction [Cg–Cg distance between the pyran and benzene rings = 3.519 (2) Å] of different layers (Fig. 2). The distance between the fluorine atom and the oxygen atom of the chromone carbonyl group [3.332 (3) Å] are far from halogen bonding (Fig.3 (bottom right)).

S2. Experimental

2-Hydroxy-3-fluoroacetophenone was prepared according to the literature method (Valoti et al. 2001). To a solution of 2-hydroxy-3-fluoroacetophenone (7.1 mmol) in N,N-dimethylformamide (15 ml) was added dropwise POCl₃ (17.7 mmol) at 273 K. 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: 57%). ¹H NMR (400 MHz, DMSO-d₆): δ = 7.58 (m, 1H), 7.88 (dd, 1H, J = 1.5 and 8.3 Hz), 7.95 (d, 1H, J = 8.3 Hz), 8.99 (s, 1H), 10.13 (s, 1H). DART-MS calcd for [C₁₀H₅F₁O₃ + H⁺]: 193.030, found 193.035. Single crystals suitable for X-ray diffraction were obtained by slow evaporation of a 2-butanone solution of the title compound at room temperature.