6-Chloro-7-methyl-4-oxo-4H-chromene-3-carbaldehyde

Yoshinobu Ishikawa

doi:10.1107/S1600536814014226

. 2014 Jun 21;70(Pt 7):o804. doi: 10.1107/S1600536814014226

6-Chloro-7-methyl-4-oxo-4H-chromene-3-carbaldehyde

Yoshinobu Ishikawa ^a,^*

PMCID: PMC4120566 PMID: 25161585

Abstract

In the title compound, C₁₁H₇ClO₃, a chlorinated and methylated 3-formylchromone derivative, the non-H atoms are essentially coplanar (r.m.s. deviation = 0.0670 Å), with the largest deviation from the least-squares plane [0.2349 (17) Å] being for the pyran carbonyl O atom. In the crystal, molecules are linked through π–π stacking interactions along the a axis [centroid–centroid distance between the pyran rings = 3.824 (6) Å] and two stacks are connected by type I halogen–halogen interactions between the Cl atoms [Cl⋯Cl = 3.397 (3) Å].

Keywords: crystal structure

Related literature

For related structures, see: Ishikawa & Motohashi (2013 ▶); Ishikawa (2014 ▶). For halogen bonding, see: Auffinger et al. (2004 ▶); Metrangolo et al. (2005 ▶); Wilcken et al. (2013 ▶); Sirimulla et al. (2013 ▶). For halogen–halogen interactions, see: Metrangolo & Resnati (2014 ▶); Mukherjee & Desiraju (2014 ▶). graphic file with name e-70-0o804-scheme1.jpg

Experimental

Crystal data

C₁₁H₇ClO₃
M _r = 222.63
Triclinic,
a = 3.824 (6) Å
b = 6.111 (9) Å
c = 19.962 (10) Å
α = 81.83 (7)°
β = 88.82 (7)°
γ = 87.04 (12)°
V = 461.1 (10) Å³
Z = 2
Mo Kα radiation
μ = 0.39 mm⁻¹
T = 100 K
0.45 × 0.20 × 0.10 mm

Data collection

Rigaku AFC-7R diffractometer
2677 measured reflections
2092 independent reflections
1784 reflections with F ² > 2σ(F ²)
R _int = 0.076
3 standard reflections every 150 reflections intensity decay: −0.3%

Refinement

R[F ² > 2σ(F ²)] = 0.034
wR(F ²) = 0.094
S = 1.08
2092 reflections
137 parameters
H-atom parameters constrained
Δρ_max = 0.43 e Å⁻³
Δρ_min = −0.44 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/S1600536814014226/tk5320sup1.cif

e-70-0o804-sup1.cif^{(24.8KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536814014226/tk5320Isup2.hkl

e-70-0o804-Isup2.hkl^{(102.9KB, hkl)}

Click here for additional data file.^{(3.8KB, cml)}

Supporting information file. DOI: 10.1107/S1600536814014226/tk5320Isup3.cml

CCDC reference: 1008807

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

Acknowledgments

The University of Shizuoka is acknowledged for instrumental support.

supplementary crystallographic information

S1. Structural commentary

Halogen bonding and halogen···halogen interactions have recently 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). We have recently reported the crystal structures of halogenated 3-formylchromone derivatives 6,8-dichloro-4-oxochromene-3-carbaldehyde (Ishikawa & Motohashi, 2013) and 6-chloro-4-oxo-4H-chromene-3-carbaldehyde (Ishikawa, 2014). Both halogen bonding between the formyl oxygen atom and the chlorine atom at 8-position and type I halogen···halogen interaction between the chlorine atoms at 6-position are observed in 6,8-dichloro-4-oxochromene-3-carbaldehyde (Fig. 3, (top). On the other hand, a van der Waals contact between the formyl oxygen atom and the chlorine atom at 6-position is found in 6-chloro-4-oxo-4H-chromene-3-carbaldehyde (Fig. 3, middle). As part of our interest in these types of chemical bonding, we herein report the crystal structure of a monochlorinated and methylated 3-formylchromone derivative 6-chloro-7-methyl-4-oxo-4H-chromene-3-carbaldehyde. The objective of this study is to reveal the inductive effect of the vicinal electron-donating group on the chlorine atom at 6-position and its interaction mode.

The mean deviation of the least-square plane for the non-hydrogen atoms is 0.0670 Å, and the largest deviation is 0.2349 (17) Å for O3 (Fig. 1).

In the crystal, the molecules are stacked with the translation-symmetry equivalentⁱ [centroid–centroid distance between the pyran rings = 3.824 (6) Å, i: x + 1, y, z], as shown in Fig. 2. In addition, a type I halogen···halogen interaction is observed between the chlorine atoms at 6-position [Cl1···Cl1ⁱⁱ = 3.397 (3) Å, C5–Cl1–Cl1ⁱⁱ = 148.41 (7)°, ii: –x, –y, –z], as shown in Fig. 3 (bottom). Thus, a contact between the formyl oxygen atom and the chlorine atom at 6-position is not observed in the title compound. The chemical nature of the chlorine atom at 6-position in the title compound should be similar to that of the chlorine one at 6-position in 6,8-dichloro-4-oxochromene-3-carbaldehyde.

S2. Synthesis and crystallization

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

S3. 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 (0 0 20) was omitted because of systematic error.