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Acta Crystallogr Sect E Struct Rep Online. 2010 August 1; 66(Pt 8): o2129.
Published online 2010 July 31. doi:  10.1107/S1600536810029211
PMCID: PMC3007304

3,3,6,6-Tetra­methyl-9-(2-nitro­phen­yl)-3,4,6,7-tetra­hydro-2H-xanthene-1,8(5H,9H)-dione

Abstract

In the title compound, C23H25NO5, the pyran ring adopts a flattened boat conformation, while the two cyclo­hexenone rings are in envelope conformations. The 3-nitro­phenyl ring is almost perpendicular to the pyran ring, making a dihedral angle of 87.1 (3)°.

Related literature

For the use of xanthenes as dyes and fluorescent materials for visualization of biomolecules and in laser technologies, see: Menchen et al. (2003 [triangle]); Banerjee & Mukherjee (1981 [triangle]). They can be converted by oxidation into xanthylium salts, which are also effective as dyes and fluorescent materials, see: Nogradi (2003 [triangle]); Kamel & Shoeb (1964 [triangle]). For the biological and pharmaceutical properties of xanthenes, see: Hideo (1981 [triangle]); Lambert et al. (1997 [triangle]); Poupelin et al. (1978 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o2129-scheme1.jpg

Experimental

Crystal data

  • C23H25NO5
  • M r = 395.44
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-66-o2129-efi1.jpg
  • a = 12.199 (2) Å
  • b = 10.510 (2) Å
  • c = 32.484 (7) Å
  • V = 4164.9 (14) Å3
  • Z = 8
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 113 K
  • 0.20 × 0.16 × 0.10 mm

Data collection

  • Rigaku Saturn CCD area-detector diffractometer
  • Absorption correction: multi-scan (CrystalClear; Rigaku, 2002 [triangle]) T min = 0.983, T max = 0.991
  • 21559 measured reflections
  • 3670 independent reflections
  • 3242 reflections with I > 2σ(I)
  • R int = 0.053

Refinement

  • R[F 2 > 2σ(F 2)] = 0.063
  • wR(F 2) = 0.144
  • S = 1.16
  • 3670 reflections
  • 267 parameters
  • H-atom parameters constrained
  • Δρmax = 0.22 e Å−3
  • Δρmin = −0.24 e Å−3

Data collection: CrystalClear (Rigaku, 2002 [triangle]); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXS97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL (Sheldrick, 2008 [triangle]); software used to prepare material for publication: SHELXTL.

Supplementary Material

Crystal structure: contains datablocks I, publication_text. DOI: 10.1107/S1600536810029211/jh2186sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810029211/jh2186Isup2.hkl

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

Acknowledgments

The authors thank the Tianjin Natural Science Foundation (07JCYBJC02200) for financial support.

supplementary crystallographic information

Comment

Xanthenes are an important class of organic compounds that find use as dyes, fluorescent materials for visualization of biomolecules and in laser technologies, due to their useful spectroscopic properties (Menchen et al., 2003; Banerjee & Mukherjee, 1981). Oxidation of these compounds can be converted to the corresponding xanthylium salts, which are also effective as dyes and fluorescent materials (Nogradi, 2003; Kamel & Shoeb, 1964). Xanthenes have also received considerable attention from many pharmaceuticals and organic chemists, actually because of the broad spectrum of their biological and pharmaceutical properties such as agricultural bactericide effects (Hideo, 1981), photodynamic therapy, anti-inflammatory activities (Poupelin et al., 1978) and antiviral effects (Lambert et al., 1997). In view of the importance of the title compound,(I), we report herein its crystal structure.

The pyran ring of the title molecule (Fig. 1) adopts a flattened boat conformation. The two cyclohexenone rings adope envelope conformation with atom C3 and C11 at the flap. The 3-nitrophenyl ring and the planar part of the pyran ring (C1/C6/C8/C13) are nearly perpendicular to each other, with a dihedral angle of 87.1 (3)°.

Experimental

A mixture of 2-nitrobenzaldehyde (212 mg, 2 mmol), dimedone (560 mg, 4 mmol), p-TSA (2 mg, 5 mol%), 4 ml of MeOH containing 2 ml of water was heated to 50 ° C in an atmosphere of argon for about 20 min. After completion of the reaction (as indicated by TLC), the reaction mixture was poured into crushed ice and stirred for about 1 h.The solid separated was filtered through a sintered funnel under suction, washed with ice-cold water (30 ml) and then recrystallized from hot ethanol to afford the product (0.213 g, 80%). A single-crystal was obtained by slow evaporation of a EtOH solution.

Refinement

The H atoms bonded to C atoms were included in the refinement in the riding model approximation, with C–H = 0.93–0.97 Å and Uiso (H) = 1.2 Ueq (C atom). For the H atoms attached to C atoms of methyl groups, their Uiso(H) =1.5Ueq(C).

Figures

Fig. 1.
A view of the Structure of (I), Showing the atom-numbering scheme. Dispacement ellipsoids are drawn at the 30% probability level.
Fig. 2.
A packing diagram of the title molecule.

Crystal data

C23H25NO5Dx = 1.261 Mg m3
Mr = 395.44Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, PbcaCell parameters from 9106 reflections
a = 12.199 (2) Åθ = 1.9–28.1°
b = 10.510 (2) ŵ = 0.09 mm1
c = 32.484 (7) ÅT = 113 K
V = 4164.9 (14) Å3Prism, white
Z = 80.20 × 0.16 × 0.10 mm
F(000) = 1680

Data collection

Rigaku Saturn CCD area-detector diffractometer3670 independent reflections
Radiation source: rotating anode3242 reflections with I > 2σ(I)
confocalRint = 0.053
Detector resolution: 7.31 pixels mm-1θmax = 25.0°, θmin = 2.5°
ω and [var phi] scansh = −14→14
Absorption correction: multi-scan (CrystalClear; Rigaku, 2002)k = −10→12
Tmin = 0.983, Tmax = 0.991l = −38→36
21559 measured reflections

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.063H-atom parameters constrained
wR(F2) = 0.144w = 1/[σ2(Fo2) + (0.0574P)2 + 1.5964P] where P = (Fo2 + 2Fc2)/3
S = 1.16(Δ/σ)max = 0.001
3670 reflectionsΔρmax = 0.22 e Å3
267 parametersΔρmin = −0.24 e Å3
0 restraintsExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0098 (8)

Special details

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)

xyzUiso*/Ueq
O10.54601 (12)0.17933 (14)0.36579 (4)0.0237 (4)
O20.25719 (14)0.45727 (16)0.40103 (5)0.0387 (5)
O30.49229 (13)0.50696 (15)0.26800 (4)0.0306 (4)
O40.77268 (15)0.56112 (18)0.42780 (6)0.0474 (5)
O50.78206 (14)0.76618 (17)0.42061 (5)0.0400 (5)
N10.73522 (16)0.66330 (19)0.41615 (5)0.0299 (5)
C10.56412 (18)0.2415 (2)0.32907 (6)0.0219 (5)
C20.64378 (18)0.1708 (2)0.30297 (6)0.0227 (5)
H2A0.60540.09960.28920.027*
H2B0.70150.13400.32080.027*
C30.69762 (18)0.2553 (2)0.27026 (6)0.0226 (5)
C40.60627 (18)0.3304 (2)0.24887 (6)0.0246 (5)
H4A0.63980.38970.22880.029*
H4B0.55960.27020.23330.029*
C50.53483 (18)0.4053 (2)0.27790 (6)0.0244 (5)
C60.51360 (17)0.3502 (2)0.31886 (6)0.0214 (5)
C70.43583 (17)0.4193 (2)0.34753 (6)0.0230 (5)
H70.36680.43800.33210.028*
C80.40825 (17)0.3317 (2)0.38289 (6)0.0238 (5)
C90.31381 (19)0.3637 (2)0.40908 (7)0.0296 (5)
C100.2868 (2)0.2742 (2)0.44399 (7)0.0343 (6)
H10A0.23610.20780.43370.041*
H10B0.24810.32240.46580.041*
C110.3870 (2)0.2095 (2)0.46289 (6)0.0298 (6)
C120.44987 (19)0.1422 (2)0.42801 (6)0.0261 (5)
H12A0.52270.11560.43830.031*
H12B0.40940.06470.41980.031*
C130.46462 (17)0.2256 (2)0.39124 (6)0.0227 (5)
C140.75809 (19)0.1729 (2)0.23874 (6)0.0278 (5)
H14A0.81820.12760.25240.042*
H14B0.78780.22720.21690.042*
H14C0.70700.11120.22680.042*
C150.78024 (19)0.3455 (2)0.29057 (7)0.0295 (5)
H15A0.83870.29570.30350.044*
H15B0.74290.39680.31150.044*
H15C0.81190.40170.26960.044*
C160.4605 (2)0.3084 (2)0.48427 (7)0.0421 (7)
H16A0.41850.35190.50580.063*
H16B0.48590.37080.46400.063*
H16C0.52380.26560.49660.063*
C170.3501 (2)0.1099 (2)0.49439 (7)0.0395 (7)
H17A0.30460.04580.48070.059*
H17B0.30750.15140.51610.059*
H17C0.41460.06870.50650.059*
C180.48347 (18)0.5456 (2)0.36303 (6)0.0237 (5)
C190.42695 (19)0.6595 (2)0.35885 (6)0.0281 (5)
H190.35650.65920.34640.034*
C200.4708 (2)0.7741 (2)0.37241 (7)0.0318 (6)
H200.43050.85070.36890.038*
C210.57294 (19)0.7774 (2)0.39100 (6)0.0296 (5)
H210.60430.85510.40020.035*
C220.62764 (18)0.6625 (2)0.39566 (6)0.0250 (5)
C230.58551 (18)0.5471 (2)0.38256 (6)0.0241 (5)
H230.62520.47040.38680.029*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0265 (9)0.0227 (9)0.0221 (7)0.0030 (7)0.0026 (6)0.0018 (6)
O20.0319 (10)0.0312 (10)0.0529 (10)0.0085 (8)0.0103 (8)0.0031 (8)
O30.0332 (10)0.0266 (10)0.0319 (8)0.0075 (8)−0.0029 (7)0.0042 (7)
O40.0405 (12)0.0360 (12)0.0655 (12)−0.0072 (9)−0.0202 (9)0.0157 (9)
O50.0310 (10)0.0320 (11)0.0572 (11)−0.0071 (8)0.0037 (8)−0.0187 (8)
N10.0283 (11)0.0318 (12)0.0297 (10)−0.0046 (10)0.0018 (8)−0.0044 (8)
C10.0237 (12)0.0211 (12)0.0209 (10)−0.0029 (10)−0.0028 (8)−0.0011 (8)
C20.0260 (12)0.0187 (12)0.0232 (10)0.0014 (10)−0.0016 (8)−0.0011 (8)
C30.0248 (12)0.0183 (12)0.0246 (10)−0.0003 (10)0.0008 (8)−0.0002 (8)
C40.0275 (12)0.0234 (12)0.0228 (10)0.0001 (10)0.0001 (9)0.0000 (9)
C50.0220 (12)0.0227 (13)0.0286 (11)−0.0012 (10)−0.0045 (9)−0.0003 (9)
C60.0214 (12)0.0191 (12)0.0236 (10)−0.0002 (9)−0.0016 (8)−0.0018 (8)
C70.0198 (11)0.0230 (12)0.0261 (11)0.0015 (10)−0.0030 (8)−0.0012 (9)
C80.0229 (12)0.0224 (12)0.0262 (10)−0.0018 (10)−0.0014 (9)−0.0016 (9)
C90.0277 (13)0.0249 (13)0.0362 (12)−0.0018 (11)0.0035 (10)−0.0045 (10)
C100.0342 (14)0.0283 (14)0.0403 (13)−0.0020 (12)0.0134 (10)−0.0021 (10)
C110.0347 (14)0.0253 (13)0.0293 (11)−0.0053 (11)0.0079 (10)−0.0030 (10)
C120.0272 (12)0.0237 (13)0.0273 (11)−0.0023 (10)0.0032 (9)0.0004 (9)
C130.0194 (11)0.0232 (13)0.0253 (10)−0.0035 (10)0.0016 (8)−0.0047 (9)
C140.0305 (13)0.0264 (13)0.0266 (11)0.0005 (11)0.0043 (9)0.0008 (9)
C150.0302 (13)0.0247 (13)0.0336 (11)−0.0027 (11)−0.0029 (9)−0.0019 (10)
C160.0536 (17)0.0411 (17)0.0318 (12)−0.0137 (14)0.0024 (11)−0.0090 (11)
C170.0483 (17)0.0366 (16)0.0337 (12)−0.0024 (13)0.0133 (11)0.0013 (11)
C180.0280 (12)0.0224 (13)0.0207 (10)0.0004 (10)0.0026 (8)−0.0021 (8)
C190.0286 (13)0.0261 (14)0.0296 (11)0.0041 (11)−0.0028 (9)0.0000 (9)
C200.0393 (15)0.0213 (13)0.0349 (12)0.0077 (11)0.0005 (10)−0.0017 (10)
C210.0364 (14)0.0240 (13)0.0283 (11)−0.0024 (11)0.0042 (10)−0.0028 (9)
C220.0255 (12)0.0261 (13)0.0236 (10)−0.0030 (10)0.0021 (8)−0.0004 (8)
C230.0265 (12)0.0211 (12)0.0246 (10)0.0021 (10)0.0018 (9)−0.0004 (9)

Geometric parameters (Å, °)

O1—C11.378 (2)C11—C171.531 (3)
O1—C131.381 (2)C11—C161.538 (3)
O2—C91.230 (3)C11—C121.540 (3)
O3—C51.230 (3)C12—C131.492 (3)
O4—N11.227 (2)C12—H12A0.9900
O5—N11.231 (2)C12—H12B0.9900
N1—C221.472 (3)C14—H14A0.9800
C1—C61.340 (3)C14—H14B0.9800
C1—C21.488 (3)C14—H14C0.9800
C2—C31.533 (3)C15—H15A0.9800
C2—H2A0.9900C15—H15B0.9800
C2—H2B0.9900C15—H15C0.9800
C3—C141.531 (3)C16—H16A0.9800
C3—C41.532 (3)C16—H16B0.9800
C3—C151.533 (3)C16—H16C0.9800
C4—C51.507 (3)C17—H17A0.9800
C4—H4A0.9900C17—H17B0.9800
C4—H4B0.9900C17—H17C0.9800
C5—C61.474 (3)C18—C191.389 (3)
C6—C71.515 (3)C18—C231.397 (3)
C7—C81.510 (3)C19—C201.389 (3)
C7—C181.534 (3)C19—H190.9500
C7—H71.0000C20—C211.385 (3)
C8—C131.338 (3)C20—H200.9500
C8—C91.471 (3)C21—C221.388 (3)
C9—C101.510 (3)C21—H210.9500
C10—C111.528 (3)C22—C231.385 (3)
C10—H10A0.9900C23—H230.9500
C10—H10B0.9900
C1—O1—C13117.83 (17)C17—C11—C12108.93 (19)
O4—N1—O5124.0 (2)C16—C11—C12110.6 (2)
O4—N1—C22117.83 (19)C13—C12—C11112.29 (18)
O5—N1—C22118.1 (2)C13—C12—H12A109.1
C6—C1—O1123.00 (18)C11—C12—H12A109.1
C6—C1—C2125.82 (18)C13—C12—H12B109.1
O1—C1—C2111.17 (17)C11—C12—H12B109.1
C1—C2—C3112.65 (18)H12A—C12—H12B107.9
C1—C2—H2A109.1C8—C13—O1122.81 (19)
C3—C2—H2A109.1C8—C13—C12126.15 (19)
C1—C2—H2B109.1O1—C13—C12111.04 (18)
C3—C2—H2B109.1C3—C14—H14A109.5
H2A—C2—H2B107.8C3—C14—H14B109.5
C14—C3—C4109.77 (17)H14A—C14—H14B109.5
C14—C3—C15108.71 (18)C3—C14—H14C109.5
C4—C3—C15110.81 (18)H14A—C14—H14C109.5
C14—C3—C2110.01 (17)H14B—C14—H14C109.5
C4—C3—C2107.53 (18)C3—C15—H15A109.5
C15—C3—C2109.99 (17)C3—C15—H15B109.5
C5—C4—C3113.96 (17)H15A—C15—H15B109.5
C5—C4—H4A108.8C3—C15—H15C109.5
C3—C4—H4A108.8H15A—C15—H15C109.5
C5—C4—H4B108.8H15B—C15—H15C109.5
C3—C4—H4B108.8C11—C16—H16A109.5
H4A—C4—H4B107.7C11—C16—H16B109.5
O3—C5—C6120.21 (19)H16A—C16—H16B109.5
O3—C5—C4122.31 (19)C11—C16—H16C109.5
C6—C5—C4117.45 (19)H16A—C16—H16C109.5
C1—C6—C5118.54 (19)H16B—C16—H16C109.5
C1—C6—C7123.00 (18)C11—C17—H17A109.5
C5—C6—C7118.46 (18)C11—C17—H17B109.5
C8—C7—C6108.39 (18)H17A—C17—H17B109.5
C8—C7—C18111.21 (16)C11—C17—H17C109.5
C6—C7—C18112.29 (18)H17A—C17—H17C109.5
C8—C7—H7108.3H17B—C17—H17C109.5
C6—C7—H7108.3C19—C18—C23118.5 (2)
C18—C7—H7108.3C19—C18—C7121.75 (19)
C13—C8—C9118.4 (2)C23—C18—C7119.76 (19)
C13—C8—C7123.21 (19)C18—C19—C20121.7 (2)
C9—C8—C7118.37 (19)C18—C19—H19119.2
O2—C9—C8120.0 (2)C20—C19—H19119.2
O2—C9—C10122.4 (2)C21—C20—C19120.4 (2)
C8—C9—C10117.6 (2)C21—C20—H20119.8
C9—C10—C11113.83 (19)C19—C20—H20119.8
C9—C10—H10A108.8C20—C21—C22117.3 (2)
C11—C10—H10A108.8C20—C21—H21121.4
C9—C10—H10B108.8C22—C21—H21121.4
C11—C10—H10B108.8C23—C22—C21123.4 (2)
H10A—C10—H10B107.7C23—C22—N1118.3 (2)
C10—C11—C17109.7 (2)C21—C22—N1118.3 (2)
C10—C11—C16110.3 (2)C22—C23—C18118.7 (2)
C17—C11—C16109.38 (19)C22—C23—H23120.7
C10—C11—C12107.88 (18)C18—C23—H23120.7
C13—O1—C1—C66.2 (3)C8—C9—C10—C1132.6 (3)
C13—O1—C1—C2−172.70 (17)C9—C10—C11—C17−173.52 (19)
C6—C1—C2—C322.0 (3)C9—C10—C11—C1665.9 (2)
O1—C1—C2—C3−159.20 (17)C9—C10—C11—C12−55.0 (3)
C1—C2—C3—C14−167.45 (17)C10—C11—C12—C1346.8 (2)
C1—C2—C3—C4−47.9 (2)C17—C11—C12—C13165.81 (19)
C1—C2—C3—C1572.8 (2)C16—C11—C12—C13−73.9 (2)
C14—C3—C4—C5174.59 (18)C9—C8—C13—O1172.13 (18)
C15—C3—C4—C5−65.3 (2)C7—C8—C13—O1−7.0 (3)
C2—C3—C4—C554.9 (2)C9—C8—C13—C12−7.8 (3)
C3—C4—C5—O3148.0 (2)C7—C8—C13—C12173.1 (2)
C3—C4—C5—C6−34.1 (3)C1—O1—C13—C8−4.3 (3)
O1—C1—C6—C5−176.97 (18)C1—O1—C13—C12175.67 (17)
C2—C1—C6—C51.8 (3)C11—C12—C13—C8−17.4 (3)
O1—C1—C6—C73.2 (3)C11—C12—C13—O1162.64 (18)
C2—C1—C6—C7−178.1 (2)C8—C7—C18—C19−112.2 (2)
O3—C5—C6—C1−177.9 (2)C6—C7—C18—C19126.2 (2)
C4—C5—C6—C14.3 (3)C8—C7—C18—C2366.7 (2)
O3—C5—C6—C72.0 (3)C6—C7—C18—C23−54.9 (2)
C4—C5—C6—C7−175.89 (18)C23—C18—C19—C202.0 (3)
C1—C6—C7—C8−12.4 (3)C7—C18—C19—C20−179.1 (2)
C5—C6—C7—C8167.72 (18)C18—C19—C20—C21−0.6 (3)
C1—C6—C7—C18110.8 (2)C19—C20—C21—C22−0.6 (3)
C5—C6—C7—C18−69.0 (2)C20—C21—C22—C230.4 (3)
C6—C7—C8—C1314.3 (3)C20—C21—C22—N1−178.68 (18)
C18—C7—C8—C13−109.6 (2)O4—N1—C22—C23−13.9 (3)
C6—C7—C8—C9−164.80 (18)O5—N1—C22—C23166.23 (19)
C18—C7—C8—C971.3 (2)O4—N1—C22—C21165.2 (2)
C13—C8—C9—O2−176.5 (2)O5—N1—C22—C21−14.7 (3)
C7—C8—C9—O22.6 (3)C21—C22—C23—C181.0 (3)
C13—C8—C9—C100.2 (3)N1—C22—C23—C18−179.92 (17)
C7—C8—C9—C10179.30 (19)C19—C18—C23—C22−2.2 (3)
O2—C9—C10—C11−150.8 (2)C7—C18—C23—C22178.92 (18)

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: JH2186).

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