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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 3| March 2012| Page o872
doi:10.1107/S1600536812007702

2-Methylxanthen-9-one

N. Vinutha,a Sumati Anthal,b V. Lakshmi Ranganatha,c Shaukath Ara Khanum,c D. Revannasiddaiah,a Rajni Kantb and Vivek K. Guptab*

aDepartment of Studies in Physics, University of Mysore, Mysore 570 006, India, bPost-Graduate Department of Physics and Electronics, University of Jammu, Jammu Tawi 180 006, India, and cDepartment of Chemistry Yuvaraja's College, University of Mysore, Mysore 570 005, India
*Correspondence e-mail: vivek_gupta2k2@hotmail.com

(Received 16 February 2012; accepted 21 February 2012; online 29 February 2012)

In the title compound, C14H10O2, the tricycle is not planar, being bent with a dihedral angle of 4.7 (1)° between the two benzene rings. In the crystal, π–π inter­actions between the six-membered rings of neighbouring mol­ecules [centroid–centroid distances = 3.580 (3) and 3.605 (3) Å] form stacks propagating along [101].

Related literature

For general background and applications of xanthones, see: Jiang et al. (2004[Jiang, D. J., Dai, Z. & Li, Y. J. (2004). Cardiovasc. Drug Rev. 22, 91-102.]); Sampath & Vijayaraghavan (2007[Sampath, P. D. & Vijayaraghavan, K. (2007). J. Biochem. Mol. Toxicol. 21, 3396-339.]); Nakatani et al. (2002[Nakatani, K., Nakahata, N., Arakawa, T., Yasuda, H. & Ohizumi, Y. (2002). Biochem. Pharmacol. 63, 73-79.]); Pinto et al. (2005[Pinto, M. M. M., Sousa, M. E. & Nascimento, M. S. J. (2005). Curr. Med. Chem. 12, 2517-2538.]). For related structures, see: Ee et al. (2010[Ee, G. C. L., Sim, W. C., Kwong, H. C., Mohamed Tahir, M. I. & Silong, S. (2010). Acta Cryst. E66, o3362-o3363.]); Boonnak et al. (2010[Boonnak, N., Chantrapromma, S., Fun, H.-K. & Karalai, C. (2010). Acta Cryst. E66, o817-o818.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Prpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data

  • C14H10O2

  • Mr = 210.22

  • Triclinic, [P \overline 1]

  • a = 8.2678 (7) Å

  • b = 8.5268 (6) Å

  • c = 8.5965 (7) Å

  • α = 92.650 (6)°

  • β = 116.592 (8)°

  • γ = 104.045 (7)°

  • V = 517.28 (7) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 293 K

  • 0.30 × 0.20 × 0.20 mm
Data collection

  • Oxford Diffraction Xcalibur Sapphire3 diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010[Oxford Diffraction (2010). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]) Tmin = 0.890, Tmax = 1.000

  • 10601 measured reflections

  • 2028 independent reflections

  • 1262 reflections with I > 2σ(I)

  • Rint = 0.033

  • Standard reflections: ?
Refinement

  • R[F2 > 2σ(F2)] = 0.052

  • wR(F2) = 0.152

  • S = 1.04

  • 2028 reflections

  • 146 parameters

  • H-atom parameters constrained

  • Δρmax = 0.13 e Å−3

  • Δρmin = −0.15 e Å−3

Data collection: CrysAlis PRO (Oxford Diffraction, 2010[Oxford Diffraction (2010). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812007702/cv5249sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812007702/cv5249Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812007702/cv5249Isup3.cml

checkCIF report


Comment top

Xanthones, a particular class of plant phytochemicals from mangosteen, are highly biologically active compounds, which possess anti-inflammatory properties such as COX inhibition, and have cardiovascular protective effects (Jiang et al., 2004; Sampath & Vijayaraghavan, 2007; Nakatani et al., 2002). Many naturally occurring xanthones and their prenylated derivatives are found to exhibit significant biological and pharmacological properties, such as antibacterial, antifungal and anti-tumor activities and it can be inferred that the presence of phenyl groups can be associated with an improvement of potency and selectivity for some of these properties (Pinto et al., 2005). As a large number of biologically active xanthene derivatives with pyran and dihydropyran rings are commonly found in nature, we were interested in obtaining these type of compounds to evaluate their antitumor activity. For this purpose, the title compound, 2-methyl-xanthen-9-one (I), was synthesized.

In (I) (Fig. 1), all bond lengths are within normal ranges (Allen et al., 1987) and comparable to those observed in related structures (Ee et al., 2010; Boonnak et al., 2010). The three ring system is not planar. The dihedral angle between the two benzene rings is 4.7 (1)°. π–π Interactions with distances Cg1···Cg2i = 3.605 (1) Å (symmetry code: 1 - x, -y, -z); Cg2···Cg2i = 3.850 (1) Å and Cg3···Cg1ii = 3.580 (1) Å [symmetry codes: (i) 1 - x, -y, -z; (ii) 2 - x, -y, 1 - z], Cg1, Cg2 and Cg3 are the centroids of C9/C14/C11–C13, C1–C4/C11/C14 and C5–C8/C13/C12 rings, respectively, form stacks of the molecules propagated in [101].

Related literature top

For general background and applications of xanthones, see: Jiang et al. (2004); Sampath & Vijayaraghavan (2007); Nakatani et al. (2002); Pinto et al. (2005). For related structures, see: Ee et al. (2010); Boonnak et al. (2010). For bond-length data, see: Allen et al. (1987).

Experimental top

(4-Benzoyl-4-methyl-phenoxy)-acetic acid ethyl ester was achieved by refluxing a mixture of 5.methyl-2-hydroxy benzophenone (2.94 g, 0.013 mol) and ethyl chloroacetate (3.18 g, 0.026 mol) in the presence of dry acetone (50 ml) and anhydrous potassium carbonate (2.69 g, 0.019 mol) for 8 h. The reaction mixture was cooled and solvent was removed by distillation. The residual mass was triturated with cold water to remove potassium carbonate and extracted with ether (3 τimes 50 ml). The ether layer was washed with 10% sodium hydroxide solution (3 τimes 50 ml) followed by water (3τimes30 ml) and then dried over anhydrous sodium sulfate and evaporated to dryness. The crude solid on recrystallization with ethanol afforded (4-benzoyl-4-methyl-phenoxy)-acetic acid ethyl ester with 90% yield. A mixture of (4-benzoyl-4-methyl-phenoxy)-acetic acid ethyl ester (1 g, 0.0033 mol) and sodium hydroxide (0.064 g, 0.0016 mol) in presence of ethyl alcohol (40 ml) was refluxed for about 7–9 hrs. After completion of reaction monitored by TLC, the reaction mixture was cooled and neutralized with 5% sodium carbonate solution. The solvent was removed by distillation and the residual mass was washed with water and recrystallized from methanol to achieve 2-methyl-xanthen-9-one with 70% yield. m.p.369–373 K; IR (Nujol):1665 cm-1 (C=O); 1H NMR (CDCl3): δ 2.3 (s, 3H, Ar—CH3), 6.9–7.6(bm, 7H, Ar—H); Anal. Cal. for C14H10O2 C, 79.98; H, 4.79; Found: C, 79.94; H, 4.76%.

Refinement top

All H atoms were positioned geometrically and were treated as riding on their parent C atoms, with C—H distances of 0.93–0.96 Å; and with Uiso(H) = 1.2-1.5 Ueq(C).

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2010); cell refinement: CrysAlis PRO (Oxford Diffraction, 2010); data reduction: CrysAlis PRO (Oxford Diffraction, 2010); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. ORTEP view of the molecule with the atom-labeling scheme. The displacement ellipsoids are drawn at the 40% probability level. H atoms are shown as small spheres of arbitrary radii.
2-Methylxanthen-9-one top
Crystal data top
C14H10O2Z = 2
Mr = 210.22F(000) = 220
Triclinic, P1Dx = 1.350 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.2678 (7) ÅCell parameters from 3639 reflections
b = 8.5268 (6) Åθ = 3.6–29.1°
c = 8.5965 (7) ŵ = 0.09 mm−1
α = 92.650 (6)°T = 293 K
β = 116.592 (8)°Block, white
γ = 104.045 (7)°0.30 × 0.20 × 0.20 mm
V = 517.28 (7) Å3
Data collection top
Oxford Diffraction Xcalibur Sapphire3
diffractometer		2028 independent reflections
Radiation source: fine-focus sealed tube1262 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.033
ω scansθmax = 26.0°, θmin = 3.6°
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2010)		h = −10→10
Tmin = 0.890, Tmax = 1.000k = −10→10
10601 measured reflectionsl = −10→10
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.052Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.152H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0652P)2 + 0.0822P]
where P = (Fo2 + 2Fc2)/3
2028 reflections(Δ/σ)max < 0.001
146 parametersΔρmax = 0.13 e Å−3
0 restraintsΔρmin = −0.15 e Å−3
Crystal data top
C14H10O2γ = 104.045 (7)°
Mr = 210.22V = 517.28 (7) Å3
Triclinic, P1Z = 2
a = 8.2678 (7) ÅMo Kα radiation
b = 8.5268 (6) ŵ = 0.09 mm−1
c = 8.5965 (7) ÅT = 293 K
α = 92.650 (6)°0.30 × 0.20 × 0.20 mm
β = 116.592 (8)°
Data collection top
Oxford Diffraction Xcalibur Sapphire3
diffractometer		2028 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2010)		1262 reflections with I > 2σ(I)
Tmin = 0.890, Tmax = 1.000Rint = 0.033
10601 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0520 restraints
wR(F2) = 0.152H-atom parameters constrained
S = 1.04Δρmax = 0.13 e Å−3
2028 reflectionsΔρmin = −0.15 e Å−3
146 parameters
Special details top

Experimental. CrysAlis PRO, Oxford Diffraction Ltd., Version 1.171.34.40 (release 27–08-2010 CrysAlis171. NET) (compiled Aug 27 2010,11:50:40) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

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 of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.7846 (3)0.1172 (2)0.0063 (2)0.0552 (5)
H10.82990.0663−0.05700.066*
C20.7434 (3)0.2613 (3)−0.0345 (3)0.0608 (6)
C30.6748 (3)0.3344 (3)0.0625 (3)0.0672 (6)
H30.64480.43150.03620.081*
C40.6505 (3)0.2675 (3)0.1948 (3)0.0658 (6)
H40.60460.31870.25740.079*
C50.7034 (3)−0.1210 (3)0.5685 (3)0.0623 (6)
H50.6586−0.06090.62490.075*
C60.7523 (3)−0.2566 (3)0.6273 (3)0.0705 (7)
H60.7410−0.28860.72480.085*
C70.8186 (3)−0.3476 (3)0.5441 (3)0.0707 (7)
H70.8514−0.44010.58550.085*
C80.8355 (3)−0.3005 (3)0.4002 (3)0.0601 (6)
H80.8802−0.36160.34450.072*
C90.8034 (3)−0.1098 (2)0.1823 (2)0.0487 (5)
O90.8493 (2)−0.19003 (18)0.09566 (19)0.0720 (5)
O100.67103 (19)0.06452 (17)0.37199 (17)0.0590 (4)
C110.6948 (3)0.1230 (2)0.2347 (2)0.0499 (5)
C120.7212 (3)−0.0736 (2)0.4230 (2)0.0494 (5)
C130.7864 (3)−0.1617 (2)0.3361 (2)0.0468 (5)
C140.7604 (3)0.0446 (2)0.1403 (2)0.0466 (5)
C150.7710 (4)0.3410 (3)−0.1775 (3)0.0837 (8)
H1530.84060.4550−0.13210.126*
H1520.64980.3312−0.27600.126*
H1510.84010.2873−0.21530.126*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0528 (13)0.0580 (13)0.0503 (12)0.0096 (10)0.0242 (10)0.0068 (9)
C20.0544 (13)0.0574 (13)0.0561 (12)0.0066 (10)0.0185 (10)0.0142 (10)
C30.0636 (15)0.0503 (12)0.0768 (15)0.0177 (11)0.0232 (12)0.0157 (11)
C40.0650 (15)0.0579 (14)0.0772 (15)0.0234 (11)0.0338 (12)0.0065 (11)
C50.0607 (14)0.0784 (15)0.0507 (12)0.0146 (12)0.0324 (11)0.0058 (11)
C60.0706 (16)0.0855 (17)0.0549 (13)0.0158 (13)0.0320 (12)0.0220 (12)
C70.0798 (17)0.0697 (15)0.0640 (13)0.0251 (13)0.0324 (12)0.0262 (11)
C80.0670 (14)0.0558 (13)0.0586 (12)0.0193 (11)0.0302 (11)0.0096 (10)
C90.0470 (11)0.0518 (11)0.0494 (11)0.0120 (9)0.0263 (9)0.0043 (9)
O90.1003 (12)0.0713 (10)0.0769 (10)0.0395 (9)0.0617 (9)0.0172 (8)
O100.0687 (10)0.0625 (9)0.0603 (9)0.0252 (7)0.0400 (7)0.0096 (7)
C110.0468 (12)0.0492 (11)0.0510 (11)0.0117 (9)0.0225 (9)0.0055 (9)
C120.0447 (11)0.0525 (12)0.0490 (11)0.0103 (9)0.0227 (9)0.0054 (9)
C130.0432 (11)0.0496 (11)0.0441 (10)0.0088 (9)0.0205 (9)0.0047 (8)
C140.0436 (11)0.0463 (11)0.0460 (10)0.0076 (9)0.0210 (9)0.0045 (8)
C150.0831 (18)0.0799 (17)0.0763 (16)0.0159 (14)0.0302 (14)0.0321 (13)
Geometric parameters (Å, º) top
C1—C21.373 (3)C7—C81.373 (3)
C1—C141.400 (2)C7—H70.9300
C1—H10.9300C8—C131.402 (3)
C2—C31.396 (3)C8—H80.9300
C2—C151.509 (3)C9—O91.225 (2)
C3—C41.367 (3)C9—C141.464 (3)
C3—H30.9300C9—C131.467 (2)
C4—C111.385 (3)O10—C121.368 (2)
C4—H40.9300O10—C111.377 (2)
C5—C61.362 (3)C11—C141.386 (3)
C5—C121.390 (3)C12—C131.385 (3)
C5—H50.9300C15—H1530.9600
C6—C71.386 (3)C15—H1520.9600
C6—H60.9300C15—H1510.9600
C2—C1—C14122.1 (2)C13—C8—H8119.6
C2—C1—H1119.0O9—C9—C14122.70 (17)
C14—C1—H1119.0O9—C9—C13122.40 (18)
C1—C2—C3117.6 (2)C14—C9—C13114.91 (16)
C1—C2—C15122.2 (2)C12—O10—C11118.91 (15)
C3—C2—C15120.2 (2)O10—C11—C4116.28 (18)
C4—C3—C2122.0 (2)O10—C11—C14122.97 (17)
C4—C3—H3119.0C4—C11—C14120.75 (19)
C2—C3—H3119.0O10—C12—C13122.48 (17)
C3—C4—C11119.3 (2)O10—C12—C5116.03 (18)
C3—C4—H4120.3C13—C12—C5121.50 (19)
C11—C4—H4120.3C12—C13—C8117.83 (18)
C6—C5—C12119.2 (2)C12—C13—C9120.58 (17)
C6—C5—H5120.4C8—C13—C9121.59 (17)
C12—C5—H5120.4C11—C14—C1118.27 (18)
C5—C6—C7121.0 (2)C11—C14—C9119.92 (17)
C5—C6—H6119.5C1—C14—C9121.80 (17)
C7—C6—H6119.5C2—C15—H153109.5
C8—C7—C6119.6 (2)C2—C15—H152109.5
C8—C7—H7120.2H153—C15—H152109.5
C6—C7—H7120.2C2—C15—H151109.5
C7—C8—C13120.9 (2)H153—C15—H151109.5
C7—C8—H8119.6H152—C15—H151109.5
C14—C1—C2—C3−0.3 (3)O10—C12—C13—C9−0.4 (3)
C14—C1—C2—C15179.37 (18)C5—C12—C13—C9179.75 (17)
C1—C2—C3—C40.7 (3)C7—C8—C13—C120.3 (3)
C15—C2—C3—C4−179.00 (19)C7—C8—C13—C9−179.92 (18)
C2—C3—C4—C110.0 (3)O9—C9—C13—C12−175.44 (19)
C12—C5—C6—C7−0.2 (3)C14—C9—C13—C124.3 (3)
C5—C6—C7—C80.1 (4)O9—C9—C13—C84.8 (3)
C6—C7—C8—C13−0.1 (3)C14—C9—C13—C8−175.48 (17)
C12—O10—C11—C4−176.87 (17)O10—C11—C14—C1−178.18 (16)
C12—O10—C11—C142.7 (3)C4—C11—C14—C11.3 (3)
C3—C4—C11—O10178.55 (17)O10—C11—C14—C91.6 (3)
C3—C4—C11—C14−1.0 (3)C4—C11—C14—C9−178.92 (17)
C11—O10—C12—C13−3.3 (3)C2—C1—C14—C11−0.7 (3)
C11—O10—C12—C5176.62 (16)C2—C1—C14—C9179.57 (18)
C6—C5—C12—O10−179.48 (18)O9—C9—C14—C11174.89 (19)
C6—C5—C12—C130.4 (3)C13—C9—C14—C11−4.9 (3)
O10—C12—C13—C8179.45 (17)O9—C9—C14—C1−5.4 (3)
C5—C12—C13—C8−0.4 (3)C13—C9—C14—C1174.86 (16)

Experimental details

Crystal data
Chemical formulaC14H10O2
Mr210.22
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)8.2678 (7), 8.5268 (6), 8.5965 (7)
α, β, γ (°)92.650 (6), 116.592 (8), 104.045 (7)
V (Å3)517.28 (7)
Z2
Radiation typeMo Kα
µ (mm−1)0.09
Crystal size (mm)0.30 × 0.20 × 0.20
Data collection
DiffractometerOxford Diffraction Xcalibur Sapphire3
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO; Oxford Diffraction, 2010)
Tmin, Tmax0.890, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections		10601, 2028, 1262
Rint0.033
(sin θ/λ)max (Å−1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.052, 0.152, 1.04
No. of reflections2028
No. of parameters146
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.13, −0.15

Computer programs: CrysAlis PRO (Oxford Diffraction, 2010), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), PLATON (Spek, 2009).

 

Acknowledgements

RK acknowledges the Department of Science and Technology for the single-crystal X-ray diffractometer sanctioned as a National Facility under project No. SR/S2/CMP-47/2003. NV is grateful to the UGC for the award of an RFSMS Fellowship. VKG is thankful to the University of Jammu for financial support. The financial support provided by the UGC, New Delhi, under the Major research project-scheme, is gratefully acknowledged.

References

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ISSN: 2056-9890
Volume 68| Part 3| March 2012| Page o872
doi:10.1107/S1600536812007702
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