9,9-Dimethyl-12-(4-nitro­phen­yl)-9,10-dihydro-12H-benzo[a]xanthen-11(8H)-one

De-Ling Li; Li-Hong Wang

doi:10.1107/S1600536809048570

. 2009 Nov 21;65(Pt 12):o3141. doi: 10.1107/S1600536809048570

9,9-Dimethyl-12-(4-nitrophenyl)-9,10-dihydro-12H-benzo[a]xanthen-11(8H)-one

De-Ling Li ^a,^*, Li-Hong Wang ^a

PMCID: PMC2972096 PMID: 21578862

Abstract

In the molecular structure of the title compound, C₂₅H₂₁NO₄, the pyran ring adopts a flattened boat conformation, while the cyclohexenone ring is in an envelope conformation. The 4-nitrophenyl ring is almost perpendicular to the pyran ring [dihedral angle = 89.39 (1)°]. In the crystal, molecules are connected by intermolecular C—H⋯O hydrogen bonds.

Related literature

For the biological activity of xanthenes and benzoxanthenes, see: Lambert et al. (1997 ▶); Poupelin et al. (1978 ▶); Ion et al. (1998 ▶); Saint-Ruf et al. (1975 ▶). graphic file with name e-65-o3141-scheme1.jpg

Experimental

Crystal data

C₂₅H₂₁NO₄
M _r = 399.43
Monoclinic,
a = 24.178 (5) Å
b = 11.078 (2) Å
c = 17.481 (4) Å
β = 119.78 (3)°
V = 4063.9 (19) Å³
Z = 8
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 113 K
0.20 × 0.18 × 0.10 mm

Data collection

Rigaku Saturn CCD area-detector diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005 ▶) T _min = 0.983, T _max = 0.999
14653 measured reflections
4007 independent reflections
3106 reflections with I > 2σ(I)
R _int = 0.044

Refinement

R[F ² > 2σ(F ²)] = 0.055
wR(F ²) = 0.153
S = 1.03
4007 reflections
274 parameters
H-atom parameters constrained
Δρ_max = 0.29 e Å⁻³
Δρ_min = −0.26 e Å⁻³

Data collection: CrystalClear (Rigaku/MSC, 2005 ▶); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXTL.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809048570/bh2257sup1.cif

e-65-o3141-sup1.cif^{(21.8KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809048570/bh2257Isup2.hkl

e-65-o3141-Isup2.hkl^{(196.5KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯O4ⁱ	0.95	2.42	3.323 (3)	159
C6—H6⋯O2ⁱⁱ	0.95	2.45	3.384 (3)	168
C18—H18B⋯O2ⁱⁱⁱ	0.98	2.43	3.355 (2)	158

Open in a new tab

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

Acknowledgments

The authors thank the Tangshan Municipal Science and Technology Commission (No. 07160213B) and Tangshan Normal College (No. 07 A02) for financial support.

supplementary crystallographic information

Comment

Xanthenes and benzoxanthenes are biologically important drug intermediates. They are cited as active oxygen heterocycles possessing anti-inflammatory (Poupelin et al., 1978) and antiviral (Lambert et al., 1997) activity. These compounds are also utilized as antagonists for paralyzing action of zoxazolamine (Saint-Ruf et al., 1975) and in photodynamic therapy (Ion et al., 1998). We report herein the crystal structure of the title compound, which belongs to this class of compounds.

The pyran ring of the title molecule (Fig. 1) adopts a flattened boat conformation. The cyclohexenone ring is in an envelope conformation with atom C15 at the flap. The 4-nitrophenyl ring and the planar part of the pyran ring (C1/C10/C12/C17) are nearly perpendicular to each other, with a dihedral angle of 89.39 (1)°. In the crystal, the molecules are connected by C—H···O hydrogen bonds (Fig. 2).

Experimental

To a mixture of 2-naphthol (1.0 mmol), benzaldehyde (1.0 mmol), and 5,5-dimethylcyclohexane-1,3-dione (1.1 mmol) was added strontium trifluoromethanesulfonate (0.1 mmol) in 1,2-dichloroethane (2 ml). The mixture was stirred at 353 K for 5 h. The progress of the reaction was monitored by TLC. After completion of the reaction, water was added and the product was extracted with ethyl acetate (3×10 ml). The organic layer was dried (MgSO₄) and evaporated, and the crude product was purified by flash chromatography on silica gel. Pure product crystallized slowly at room temperature in ethanol. A single-crystal was obtained by slow evaporation of a solution in ethanol.