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

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3,3-Di­methyl-1,2,3,4,6,11-hexa­hydro­benzo[d]naphtho[2,3-b]furan-1,6,11-trione

aDepartment of Chemistry and Chemical Engineering, Southeast University, Nanjing, People's Republic of China
*Correspondence e-mail: njuhhy@hotmail.com

(Received 11 July 2008; accepted 11 July 2008; online 19 July 2008)

In the title compound, C18H14O4, the cyclo­hexene ring adopts a sofa conformation. In the crystalline state, the mol­ecules are linked into a chain by weak inter­molecular C—H⋯O hydrogen bonds.

Related literature

For related literature, see: Correa & Romo (1966[Correa, J. & Romo, J. (1966). Tetrahedron, 22, 685-691.]); Greve & Friedrichsen (2000[Greve, S. & Friedrichsen, W. (2000). Prog. Heterocycl. Chem. 12, 134-160.]); Hirai et al. (1999[Hirai, K. I., Koyama, J., Pan, J., Simamura, E., Shimada, H., Yamori, T., Sato, S., Tagahara, K. & Tsuruo, T. (1999). Cancer Detect. Prev. 23, 539-550.]); Hu et al. (2005[Hu, H.-Y., Ye, Z., Wang, L. & Xu, J.-H. (2005). Synthesis, pp. 1605-1610.]); Ito et al. (2000[Ito, C., Katsuno, S., Kondo, Y., Tan, H. T.-W. & Furukawa, H. (2000). Chem. Pharm. Bull. 48, 339-343.]). For related structures, see: Goldstein et al. (1975[Goldstein, P. (1975). Acta Cryst. B31, 2086-2097.]); Park et al. (1992[Park, I. Y., Kim, B. K. & Kim, Y. B. (1992). Arch. Pharm. Res. 15, 52-57.]).

[Scheme 1]

Experimental

Crystal data
  • C18H14O4

  • Mr = 294.29

  • Triclinic, [P \overline 1]

  • a = 5.8080 (12) Å

  • b = 6.7510 (14) Å

  • c = 18.332 (4) Å

  • α = 89.82 (3)°

  • β = 81.32 (3)°

  • γ = 78.18 (3)°

  • V = 695.2 (2) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 293 (2) K

  • 0.25 × 0.18 × 0.16 mm

Data collection
  • Bruker APEX CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2000[Sheldrick, G. M. (2000). SADABS. University of Göttingen, Germany.]) Tmin = 0.976, Tmax = 0.984

  • 2958 measured reflections

  • 2676 independent reflections

  • 1845 reflections with I > 2σ(I)

  • Rint = 0.018

Refinement
  • R[F2 > 2σ(F2)] = 0.047

  • wR(F2) = 0.137

  • S = 1.07

  • 2676 reflections

  • 199 parameters

  • H-atom parameters constrained

  • Δρmax = 0.16 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C16—H16A⋯O4i 0.93 2.54 3.177 (3) 126
Symmetry code: (i) x-1, y+1, z.

Data collection: SMART (Bruker, 2000[Bruker (2000). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SMART; data reduction: SAINT (Bruker, 2000[Bruker (2000). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Furan derivatives and annulated furan derivatives widely occur in nature. Many of these naturally occurring furan and annulated furan derivatives and their unnatural analogs have a wide range of biological activity and are important precursors for the synthesis of natural products (Greve & Friedrichsen, 2000). Especially, naphtho[2,3-b]furan-4,9-dione derivatives as represented by avicequinones (Ito et al., 2000) and maturinones (Correa & Romo, 1966) have shown a diversity of biological activities of medical importance, such as anticancer, antibacterial and anti-inflammatory activity (Hirai et al., 1999). Recently, we had reported an one-pot synthesis method for naphtho[2,3-b]furan-4,9-dione derivatives by reacting 2,3-dichloro-1,4-naphthoquinone with 1,3-dicarbonyl compounds (Hu et al., 2005).

The title compound, C18H14O4, is a naphtho[2,3-b]furan-4,9-dione derivative. It is formed as one product from refluxing 2,3-dichloro-1,4-naphthoquione, K2CO3 and 5,5-dimethylcyclohexane-1,3-dione in MeCN for 6 h. In the crystalline state, the molecules are linked to a one-dimensional chain by intermolecular weak C—H···O hydrogen bonds (Table 1).

Related literature top

For related literature, see: Correa & Romo (1966); Greve & Friedrichsen (2000); Hirai et al. (1999); Hu et al. (2005); Ito et al. (2000). For related structures, see: Goldstein et al. (1975); Park et al. (1992).

Experimental top

A mixture of 2,3-dichloro-1,4-naphthoquione (0.227 g, 1.0 mmol), K2CO3 (0.345 g, 2.5 mmol) and 5,5-dimethylcyclohexane-1,3-dione (0.154 g, 1.1 mmol) in MeCN (15 ml) was stirred at reflux temperature for 6 h. The reaction mixture was poured into H2O (150 ml) and filtered. The collected solid product was separated by silica gel column chromatography [petroleum ether - EtOAc (10:1)] yield the title compound (0.118 g, 40%) as a yellow solid. Single crystals suitable for X-ray crystallographic analysis were grown by slow evaporation of solvent from petroleum ether (b.p. 333–363 K)-ethyl acetate (3/1 v/v).

Refinement top

H atoms were positioned geometrically and refined using a riding model with C—H = 0.93–0.97 Å and with Uiso(H) = 1.2 times Ueq(C) or Uiso(H) = 1.5 times Ueq(Cmethyl).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SMART (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with 30% displacement ellipsoids.
[Figure 2] Fig. 2. Hydrogen-bonding of the title compound.
3,3-Dimethyl-1,2,3,4,6,11-hexahydrobenzo[d]naphtho[2,3-b]furan- 1,6,11-trione top
Crystal data top
C18H14O4Z = 2
Mr = 294.29F(000) = 308
Triclinic, P1Dx = 1.406 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 5.8080 (12) ÅCell parameters from 810 reflections
b = 6.7510 (14) Åθ = 2.5–28.0°
c = 18.332 (4) ŵ = 0.10 mm1
α = 89.82 (3)°T = 293 K
β = 81.32 (3)°Block, yellow
γ = 78.18 (3)°0.25 × 0.18 × 0.16 mm
V = 695.2 (2) Å3
Data collection top
Bruker APEX CCD
diffractometer
2676 independent reflections
Radiation source: fine-focus sealed tube1845 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.018
ϕ and ω scansθmax = 26.0°, θmin = 1.1°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2000)
h = 06
Tmin = 0.976, Tmax = 0.984k = 88
2958 measured reflectionsl = 2121
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)] = 0.047Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.137H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.0661P)2 + 0.1193P]
where P = (Fo2 + 2Fc2)/3
2676 reflections(Δ/σ)max < 0.001
199 parametersΔρmax = 0.16 e Å3
0 restraintsΔρmin = 0.23 e Å3
Crystal data top
C18H14O4γ = 78.18 (3)°
Mr = 294.29V = 695.2 (2) Å3
Triclinic, P1Z = 2
a = 5.8080 (12) ÅMo Kα radiation
b = 6.7510 (14) ŵ = 0.10 mm1
c = 18.332 (4) ÅT = 293 K
α = 89.82 (3)°0.25 × 0.18 × 0.16 mm
β = 81.32 (3)°
Data collection top
Bruker APEX CCD
diffractometer
2676 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2000)
1845 reflections with I > 2σ(I)
Tmin = 0.976, Tmax = 0.984Rint = 0.018
2958 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0470 restraints
wR(F2) = 0.137H-atom parameters constrained
S = 1.08Δρmax = 0.16 e Å3
2676 reflectionsΔρmin = 0.23 e Å3
199 parameters
Special details top

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
O10.1220 (3)1.1681 (3)0.34222 (12)0.0843 (7)
O20.6416 (2)0.9262 (2)0.22339 (7)0.0410 (4)
O30.0036 (3)1.4623 (2)0.22564 (10)0.0632 (5)
O40.9115 (3)1.1186 (2)0.11462 (10)0.0632 (5)
C10.2866 (5)0.5132 (4)0.41299 (15)0.0674 (7)
H1A0.43840.44860.42540.081*
H1B0.24480.43300.37590.081*
H1C0.16800.52620.45620.081*
C20.3705 (4)0.8498 (4)0.44217 (13)0.0619 (7)
H2A0.52190.78380.45450.074*
H2B0.25230.86490.48560.074*
H2C0.38120.98090.42320.074*
C30.3004 (4)0.7223 (3)0.38363 (12)0.0463 (5)
C40.0571 (4)0.8275 (4)0.36332 (13)0.0531 (6)
H4A0.00990.73830.32960.064*
H4B0.05970.84440.40780.064*
C50.0481 (3)1.0297 (4)0.32872 (12)0.0498 (6)
C60.2637 (3)1.0420 (3)0.27647 (11)0.0406 (5)
C70.4580 (3)0.8876 (3)0.27275 (11)0.0381 (5)
C80.4861 (3)0.6996 (3)0.31386 (11)0.0413 (5)
H8A0.64450.66710.32730.050*
H8B0.46790.58930.28290.050*
C90.5599 (3)1.1101 (3)0.19527 (11)0.0394 (5)
C100.3304 (3)1.1890 (3)0.22546 (11)0.0394 (5)
C110.2091 (3)1.3861 (3)0.20166 (11)0.0419 (5)
C120.3557 (3)1.4922 (3)0.14706 (11)0.0407 (5)
C130.5943 (3)1.4062 (3)0.11906 (11)0.0405 (5)
C140.7101 (3)1.2020 (3)0.14072 (12)0.0430 (5)
C150.2569 (4)1.6823 (3)0.12476 (12)0.0489 (6)
H15A0.09911.74030.14280.059*
C160.3895 (4)1.7868 (3)0.07620 (13)0.0556 (6)
H16A0.32051.91410.06120.067*
C170.6245 (4)1.7035 (3)0.04972 (13)0.0568 (6)
H17A0.71481.77520.01760.068*
C180.7246 (4)1.5134 (3)0.07112 (12)0.0497 (5)
H18A0.88271.45680.05290.060*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0402 (10)0.0837 (13)0.1077 (16)0.0104 (9)0.0245 (10)0.0054 (11)
O20.0272 (7)0.0433 (8)0.0473 (8)0.0004 (6)0.0012 (6)0.0034 (6)
O30.0309 (8)0.0669 (11)0.0782 (12)0.0111 (7)0.0054 (8)0.0014 (8)
O40.0357 (8)0.0517 (9)0.0847 (12)0.0102 (7)0.0190 (8)0.0122 (8)
C10.0565 (15)0.0743 (18)0.0711 (17)0.0243 (13)0.0057 (13)0.0130 (13)
C20.0604 (15)0.0814 (18)0.0472 (13)0.0245 (13)0.0052 (11)0.0070 (12)
C30.0344 (11)0.0585 (13)0.0481 (12)0.0174 (9)0.0019 (9)0.0011 (10)
C40.0285 (11)0.0664 (15)0.0640 (15)0.0170 (10)0.0045 (10)0.0065 (11)
C50.0266 (11)0.0655 (14)0.0547 (13)0.0084 (10)0.0004 (9)0.0064 (11)
C60.0267 (10)0.0484 (12)0.0454 (12)0.0058 (8)0.0037 (8)0.0069 (9)
C70.0270 (10)0.0463 (11)0.0404 (11)0.0089 (8)0.0017 (8)0.0037 (9)
C80.0311 (10)0.0475 (12)0.0456 (12)0.0102 (8)0.0043 (9)0.0014 (9)
C90.0290 (10)0.0403 (11)0.0444 (11)0.0014 (8)0.0032 (8)0.0013 (9)
C100.0268 (10)0.0455 (11)0.0426 (11)0.0011 (8)0.0034 (8)0.0079 (9)
C110.0277 (10)0.0472 (12)0.0454 (12)0.0046 (8)0.0052 (8)0.0104 (9)
C120.0334 (10)0.0435 (11)0.0416 (11)0.0033 (8)0.0095 (9)0.0073 (9)
C130.0336 (10)0.0414 (11)0.0416 (11)0.0030 (8)0.0047 (8)0.0030 (8)
C140.0301 (10)0.0427 (11)0.0501 (12)0.0008 (8)0.0013 (9)0.0024 (9)
C150.0392 (11)0.0472 (12)0.0535 (13)0.0085 (9)0.0093 (10)0.0057 (10)
C160.0558 (14)0.0440 (12)0.0605 (15)0.0064 (10)0.0111 (12)0.0029 (10)
C170.0540 (14)0.0496 (13)0.0616 (15)0.0021 (11)0.0041 (12)0.0078 (11)
C180.0384 (11)0.0490 (12)0.0548 (13)0.0015 (9)0.0006 (10)0.0039 (10)
Geometric parameters (Å, º) top
O1—C51.208 (3)C6—C101.432 (3)
O2—C71.358 (2)C7—C81.467 (3)
O2—C91.364 (2)C8—H8A0.9700
O3—C111.214 (2)C8—H8B0.9700
O4—C141.216 (2)C9—C101.362 (3)
C1—C31.522 (3)C9—C141.449 (3)
C1—H1A0.9600C10—C111.470 (3)
C1—H1B0.9600C11—C121.492 (3)
C1—H1C0.9600C12—C151.382 (3)
C2—C31.530 (3)C12—C131.406 (3)
C2—H2A0.9600C13—C181.374 (3)
C2—H2B0.9600C13—C141.486 (3)
C2—H2C0.9600C15—C161.377 (3)
C3—C81.530 (3)C15—H15A0.9300
C3—C41.545 (3)C16—C171.379 (3)
C4—C51.498 (3)C16—H16A0.9300
C4—H4A0.9700C17—C181.378 (3)
C4—H4B0.9700C17—H17A0.9300
C5—C61.474 (3)C18—H18A0.9300
C6—C71.364 (3)
C7—O2—C9105.92 (14)C7—C8—H8A109.6
C3—C1—H1A109.5C3—C8—H8A109.6
C3—C1—H1B109.5C7—C8—H8B109.6
H1A—C1—H1B109.5C3—C8—H8B109.6
C3—C1—H1C109.5H8A—C8—H8B108.1
H1A—C1—H1C109.5C10—C9—O2111.59 (18)
H1B—C1—H1C109.5C10—C9—C14126.95 (19)
C3—C2—H2A109.5O2—C9—C14121.46 (16)
C3—C2—H2B109.5C9—C10—C6105.23 (18)
H2A—C2—H2B109.5C9—C10—C11119.84 (19)
C3—C2—H2C109.5C6—C10—C11134.92 (17)
H2A—C2—H2C109.5O3—C11—C10122.8 (2)
H2B—C2—H2C109.5O3—C11—C12121.16 (19)
C1—C3—C8109.05 (18)C10—C11—C12116.04 (16)
C1—C3—C2109.7 (2)C15—C12—C13118.9 (2)
C8—C3—C2109.88 (17)C15—C12—C11119.26 (18)
C1—C3—C4109.92 (18)C13—C12—C11121.79 (18)
C8—C3—C4108.39 (18)C18—C13—C12119.57 (19)
C2—C3—C4109.86 (19)C18—C13—C14119.02 (18)
C5—C4—C3115.97 (17)C12—C13—C14121.41 (19)
C5—C4—H4A108.3O4—C14—C9122.99 (19)
C3—C4—H4A108.3O4—C14—C13123.17 (19)
C5—C4—H4B108.3C9—C14—C13113.84 (16)
C3—C4—H4B108.3C16—C15—C12120.7 (2)
H4A—C4—H4B107.4C16—C15—H15A119.6
O1—C5—C6123.7 (2)C12—C15—H15A119.6
O1—C5—C4122.6 (2)C15—C16—C17120.2 (2)
C6—C5—C4113.70 (18)C15—C16—H16A119.9
C7—C6—C10106.29 (17)C17—C16—H16A119.9
C7—C6—C5118.9 (2)C18—C17—C16119.6 (2)
C10—C6—C5134.80 (19)C18—C17—H17A120.2
O2—C7—C6110.97 (18)C16—C17—H17A120.2
O2—C7—C8120.29 (16)C13—C18—C17120.9 (2)
C6—C7—C8128.74 (18)C13—C18—H18A119.5
C7—C8—C3110.45 (17)C17—C18—H18A119.5
C1—C3—C4—C5175.99 (19)C5—C6—C10—C112.8 (4)
C8—C3—C4—C556.9 (2)C9—C10—C11—O3178.7 (2)
C2—C3—C4—C563.2 (2)C6—C10—C11—O30.3 (4)
C3—C4—C5—O1142.1 (2)C9—C10—C11—C122.9 (3)
C3—C4—C5—C638.6 (3)C6—C10—C11—C12178.1 (2)
O1—C5—C6—C7171.1 (2)O3—C11—C12—C151.5 (3)
C4—C5—C6—C79.6 (3)C10—C11—C12—C15177.03 (17)
O1—C5—C6—C106.8 (4)O3—C11—C12—C13179.7 (2)
C4—C5—C6—C10172.5 (2)C10—C11—C12—C131.2 (3)
C9—O2—C7—C60.1 (2)C15—C12—C13—C180.8 (3)
C9—O2—C7—C8179.77 (17)C11—C12—C13—C18177.42 (19)
C10—C6—C7—O20.0 (2)C15—C12—C13—C14179.75 (18)
C5—C6—C7—O2178.41 (17)C11—C12—C13—C142.0 (3)
C10—C6—C7—C8179.67 (19)C10—C9—C14—O4177.5 (2)
C5—C6—C7—C81.2 (3)O2—C9—C14—O43.3 (3)
O2—C7—C8—C3159.23 (17)C10—C9—C14—C131.8 (3)
C6—C7—C8—C320.4 (3)O2—C9—C14—C13177.40 (17)
C1—C3—C8—C7164.09 (18)C18—C13—C14—O44.7 (3)
C2—C3—C8—C775.6 (2)C12—C13—C14—O4175.9 (2)
C4—C3—C8—C744.4 (2)C18—C13—C14—C9176.00 (19)
C7—O2—C9—C100.1 (2)C12—C13—C14—C93.4 (3)
C7—O2—C9—C14179.43 (18)C13—C12—C15—C160.3 (3)
O2—C9—C10—C60.1 (2)C11—C12—C15—C16178.01 (19)
C14—C9—C10—C6179.36 (19)C12—C15—C16—C170.7 (3)
O2—C9—C10—C11179.37 (16)C15—C16—C17—C181.2 (4)
C14—C9—C10—C111.4 (3)C12—C13—C18—C170.4 (3)
C7—C6—C10—C90.0 (2)C14—C13—C18—C17179.8 (2)
C5—C6—C10—C9178.1 (2)C16—C17—C18—C130.6 (4)
C7—C6—C10—C11179.2 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C16—H16A···O4i0.932.543.177 (3)126
Symmetry code: (i) x1, y+1, z.

Experimental details

Crystal data
Chemical formulaC18H14O4
Mr294.29
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)5.8080 (12), 6.7510 (14), 18.332 (4)
α, β, γ (°)89.82 (3), 81.32 (3), 78.18 (3)
V3)695.2 (2)
Z2
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.25 × 0.18 × 0.16
Data collection
DiffractometerBruker APEX CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2000)
Tmin, Tmax0.976, 0.984
No. of measured, independent and
observed [I > 2σ(I)] reflections
2958, 2676, 1845
Rint0.018
(sin θ/λ)max1)0.616
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.047, 0.137, 1.08
No. of reflections2676
No. of parameters199
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.16, 0.23

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C16—H16A···O4i0.932.543.177 (3)125.7
Symmetry code: (i) x1, y+1, z.
 

Acknowledgements

The author thanks the Program for Young Excellent Talents in Southeast University for financial support.

References

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