organic compounds
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
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); 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
Crystal data
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Refinement
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Data collection: SMART (Bruker, 2000); cell SMART; data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.
Supporting information
10.1107/S1600536808021600/bt2746sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536808021600/bt2746Isup2.hkl
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
[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).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).
Data collection: SMART (Bruker, 2000); cell
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).Fig. 1. The molecular structure of the title compound with 30% displacement ellipsoids. | |
Fig. 2. Hydrogen-bonding of the title compound. |
C18H14O4 | Z = 2 |
Mr = 294.29 | F(000) = 308 |
Triclinic, P1 | Dx = 1.406 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 5.8080 (12) Å | Cell parameters from 810 reflections |
b = 6.7510 (14) Å | θ = 2.5–28.0° |
c = 18.332 (4) Å | µ = 0.10 mm−1 |
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 |
Bruker APEX CCD diffractometer | 2676 independent reflections |
Radiation source: fine-focus sealed tube | 1845 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.018 |
ϕ and ω scans | θmax = 26.0°, θmin = 1.1° |
Absorption correction: multi-scan (SADABS; Sheldrick, 2000) | h = 0→6 |
Tmin = 0.976, Tmax = 0.984 | k = −8→8 |
2958 measured reflections | l = −21→21 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.047 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.137 | H-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 parameters | Δρmax = 0.16 e Å−3 |
0 restraints | Δρmin = −0.23 e Å−3 |
C18H14O4 | γ = 78.18 (3)° |
Mr = 294.29 | V = 695.2 (2) Å3 |
Triclinic, P1 | Z = 2 |
a = 5.8080 (12) Å | Mo Kα radiation |
b = 6.7510 (14) Å | µ = 0.10 mm−1 |
c = 18.332 (4) Å | T = 293 K |
α = 89.82 (3)° | 0.25 × 0.18 × 0.16 mm |
β = 81.32 (3)° |
Bruker APEX CCD diffractometer | 2676 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 2000) | 1845 reflections with I > 2σ(I) |
Tmin = 0.976, Tmax = 0.984 | Rint = 0.018 |
2958 measured reflections |
R[F2 > 2σ(F2)] = 0.047 | 0 restraints |
wR(F2) = 0.137 | H-atom parameters constrained |
S = 1.08 | Δρmax = 0.16 e Å−3 |
2676 reflections | Δρmin = −0.23 e Å−3 |
199 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
O1 | −0.1220 (3) | 1.1681 (3) | 0.34222 (12) | 0.0843 (7) | |
O2 | 0.6416 (2) | 0.9262 (2) | 0.22339 (7) | 0.0410 (4) | |
O3 | 0.0036 (3) | 1.4623 (2) | 0.22564 (10) | 0.0632 (5) | |
O4 | 0.9115 (3) | 1.1186 (2) | 0.11462 (10) | 0.0632 (5) | |
C1 | 0.2866 (5) | 0.5132 (4) | 0.41299 (15) | 0.0674 (7) | |
H1A | 0.4384 | 0.4486 | 0.4254 | 0.081* | |
H1B | 0.2448 | 0.4330 | 0.3759 | 0.081* | |
H1C | 0.1680 | 0.5262 | 0.4562 | 0.081* | |
C2 | 0.3705 (4) | 0.8498 (4) | 0.44217 (13) | 0.0619 (7) | |
H2A | 0.5219 | 0.7838 | 0.4545 | 0.074* | |
H2B | 0.2523 | 0.8649 | 0.4856 | 0.074* | |
H2C | 0.3812 | 0.9809 | 0.4232 | 0.074* | |
C3 | 0.3004 (4) | 0.7223 (3) | 0.38363 (12) | 0.0463 (5) | |
C4 | 0.0571 (4) | 0.8275 (4) | 0.36332 (13) | 0.0531 (6) | |
H4A | 0.0099 | 0.7383 | 0.3296 | 0.064* | |
H4B | −0.0597 | 0.8444 | 0.4078 | 0.064* | |
C5 | 0.0481 (3) | 1.0297 (4) | 0.32872 (12) | 0.0498 (6) | |
C6 | 0.2637 (3) | 1.0420 (3) | 0.27647 (11) | 0.0406 (5) | |
C7 | 0.4580 (3) | 0.8876 (3) | 0.27275 (11) | 0.0381 (5) | |
C8 | 0.4861 (3) | 0.6996 (3) | 0.31386 (11) | 0.0413 (5) | |
H8A | 0.6445 | 0.6671 | 0.3273 | 0.050* | |
H8B | 0.4679 | 0.5893 | 0.2829 | 0.050* | |
C9 | 0.5599 (3) | 1.1101 (3) | 0.19527 (11) | 0.0394 (5) | |
C10 | 0.3304 (3) | 1.1890 (3) | 0.22546 (11) | 0.0394 (5) | |
C11 | 0.2091 (3) | 1.3861 (3) | 0.20166 (11) | 0.0419 (5) | |
C12 | 0.3557 (3) | 1.4922 (3) | 0.14706 (11) | 0.0407 (5) | |
C13 | 0.5943 (3) | 1.4062 (3) | 0.11906 (11) | 0.0405 (5) | |
C14 | 0.7101 (3) | 1.2020 (3) | 0.14072 (12) | 0.0430 (5) | |
C15 | 0.2569 (4) | 1.6823 (3) | 0.12476 (12) | 0.0489 (6) | |
H15A | 0.0991 | 1.7403 | 0.1428 | 0.059* | |
C16 | 0.3895 (4) | 1.7868 (3) | 0.07620 (13) | 0.0556 (6) | |
H16A | 0.3205 | 1.9141 | 0.0612 | 0.067* | |
C17 | 0.6245 (4) | 1.7035 (3) | 0.04972 (13) | 0.0568 (6) | |
H17A | 0.7148 | 1.7752 | 0.0176 | 0.068* | |
C18 | 0.7246 (4) | 1.5134 (3) | 0.07112 (12) | 0.0497 (5) | |
H18A | 0.8827 | 1.4568 | 0.0529 | 0.060* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0402 (10) | 0.0837 (13) | 0.1077 (16) | 0.0104 (9) | 0.0245 (10) | 0.0054 (11) |
O2 | 0.0272 (7) | 0.0433 (8) | 0.0473 (8) | −0.0004 (6) | 0.0012 (6) | 0.0034 (6) |
O3 | 0.0309 (8) | 0.0669 (11) | 0.0782 (12) | 0.0111 (7) | 0.0054 (8) | 0.0014 (8) |
O4 | 0.0357 (8) | 0.0517 (9) | 0.0847 (12) | 0.0102 (7) | 0.0190 (8) | 0.0122 (8) |
C1 | 0.0565 (15) | 0.0743 (18) | 0.0711 (17) | −0.0243 (13) | 0.0057 (13) | 0.0130 (13) |
C2 | 0.0604 (15) | 0.0814 (18) | 0.0472 (13) | −0.0245 (13) | −0.0052 (11) | −0.0070 (12) |
C3 | 0.0344 (11) | 0.0585 (13) | 0.0481 (12) | −0.0174 (9) | −0.0019 (9) | −0.0011 (10) |
C4 | 0.0285 (11) | 0.0664 (15) | 0.0640 (15) | −0.0170 (10) | 0.0045 (10) | −0.0065 (11) |
C5 | 0.0266 (11) | 0.0655 (14) | 0.0547 (13) | −0.0084 (10) | 0.0004 (9) | −0.0064 (11) |
C6 | 0.0267 (10) | 0.0484 (12) | 0.0454 (12) | −0.0058 (8) | −0.0037 (8) | −0.0069 (9) |
C7 | 0.0270 (10) | 0.0463 (11) | 0.0404 (11) | −0.0089 (8) | −0.0017 (8) | −0.0037 (9) |
C8 | 0.0311 (10) | 0.0475 (12) | 0.0456 (12) | −0.0102 (8) | −0.0043 (9) | −0.0014 (9) |
C9 | 0.0290 (10) | 0.0403 (11) | 0.0444 (11) | 0.0014 (8) | −0.0032 (8) | −0.0013 (9) |
C10 | 0.0268 (10) | 0.0455 (11) | 0.0426 (11) | −0.0011 (8) | −0.0034 (8) | −0.0079 (9) |
C11 | 0.0277 (10) | 0.0472 (12) | 0.0454 (12) | 0.0046 (8) | −0.0052 (8) | −0.0104 (9) |
C12 | 0.0334 (10) | 0.0435 (11) | 0.0416 (11) | 0.0033 (8) | −0.0095 (9) | −0.0073 (9) |
C13 | 0.0336 (10) | 0.0414 (11) | 0.0416 (11) | 0.0030 (8) | −0.0047 (8) | −0.0030 (8) |
C14 | 0.0301 (10) | 0.0427 (11) | 0.0501 (12) | 0.0008 (8) | 0.0013 (9) | −0.0024 (9) |
C15 | 0.0392 (11) | 0.0472 (12) | 0.0535 (13) | 0.0085 (9) | −0.0093 (10) | −0.0057 (10) |
C16 | 0.0558 (14) | 0.0440 (12) | 0.0605 (15) | 0.0064 (10) | −0.0111 (12) | 0.0029 (10) |
C17 | 0.0540 (14) | 0.0496 (13) | 0.0616 (15) | −0.0021 (11) | −0.0041 (12) | 0.0078 (11) |
C18 | 0.0384 (11) | 0.0490 (12) | 0.0548 (13) | 0.0015 (9) | 0.0006 (10) | 0.0039 (10) |
O1—C5 | 1.208 (3) | C6—C10 | 1.432 (3) |
O2—C7 | 1.358 (2) | C7—C8 | 1.467 (3) |
O2—C9 | 1.364 (2) | C8—H8A | 0.9700 |
O3—C11 | 1.214 (2) | C8—H8B | 0.9700 |
O4—C14 | 1.216 (2) | C9—C10 | 1.362 (3) |
C1—C3 | 1.522 (3) | C9—C14 | 1.449 (3) |
C1—H1A | 0.9600 | C10—C11 | 1.470 (3) |
C1—H1B | 0.9600 | C11—C12 | 1.492 (3) |
C1—H1C | 0.9600 | C12—C15 | 1.382 (3) |
C2—C3 | 1.530 (3) | C12—C13 | 1.406 (3) |
C2—H2A | 0.9600 | C13—C18 | 1.374 (3) |
C2—H2B | 0.9600 | C13—C14 | 1.486 (3) |
C2—H2C | 0.9600 | C15—C16 | 1.377 (3) |
C3—C8 | 1.530 (3) | C15—H15A | 0.9300 |
C3—C4 | 1.545 (3) | C16—C17 | 1.379 (3) |
C4—C5 | 1.498 (3) | C16—H16A | 0.9300 |
C4—H4A | 0.9700 | C17—C18 | 1.378 (3) |
C4—H4B | 0.9700 | C17—H17A | 0.9300 |
C5—C6 | 1.474 (3) | C18—H18A | 0.9300 |
C6—C7 | 1.364 (3) | ||
C7—O2—C9 | 105.92 (14) | C7—C8—H8A | 109.6 |
C3—C1—H1A | 109.5 | C3—C8—H8A | 109.6 |
C3—C1—H1B | 109.5 | C7—C8—H8B | 109.6 |
H1A—C1—H1B | 109.5 | C3—C8—H8B | 109.6 |
C3—C1—H1C | 109.5 | H8A—C8—H8B | 108.1 |
H1A—C1—H1C | 109.5 | C10—C9—O2 | 111.59 (18) |
H1B—C1—H1C | 109.5 | C10—C9—C14 | 126.95 (19) |
C3—C2—H2A | 109.5 | O2—C9—C14 | 121.46 (16) |
C3—C2—H2B | 109.5 | C9—C10—C6 | 105.23 (18) |
H2A—C2—H2B | 109.5 | C9—C10—C11 | 119.84 (19) |
C3—C2—H2C | 109.5 | C6—C10—C11 | 134.92 (17) |
H2A—C2—H2C | 109.5 | O3—C11—C10 | 122.8 (2) |
H2B—C2—H2C | 109.5 | O3—C11—C12 | 121.16 (19) |
C1—C3—C8 | 109.05 (18) | C10—C11—C12 | 116.04 (16) |
C1—C3—C2 | 109.7 (2) | C15—C12—C13 | 118.9 (2) |
C8—C3—C2 | 109.88 (17) | C15—C12—C11 | 119.26 (18) |
C1—C3—C4 | 109.92 (18) | C13—C12—C11 | 121.79 (18) |
C8—C3—C4 | 108.39 (18) | C18—C13—C12 | 119.57 (19) |
C2—C3—C4 | 109.86 (19) | C18—C13—C14 | 119.02 (18) |
C5—C4—C3 | 115.97 (17) | C12—C13—C14 | 121.41 (19) |
C5—C4—H4A | 108.3 | O4—C14—C9 | 122.99 (19) |
C3—C4—H4A | 108.3 | O4—C14—C13 | 123.17 (19) |
C5—C4—H4B | 108.3 | C9—C14—C13 | 113.84 (16) |
C3—C4—H4B | 108.3 | C16—C15—C12 | 120.7 (2) |
H4A—C4—H4B | 107.4 | C16—C15—H15A | 119.6 |
O1—C5—C6 | 123.7 (2) | C12—C15—H15A | 119.6 |
O1—C5—C4 | 122.6 (2) | C15—C16—C17 | 120.2 (2) |
C6—C5—C4 | 113.70 (18) | C15—C16—H16A | 119.9 |
C7—C6—C10 | 106.29 (17) | C17—C16—H16A | 119.9 |
C7—C6—C5 | 118.9 (2) | C18—C17—C16 | 119.6 (2) |
C10—C6—C5 | 134.80 (19) | C18—C17—H17A | 120.2 |
O2—C7—C6 | 110.97 (18) | C16—C17—H17A | 120.2 |
O2—C7—C8 | 120.29 (16) | C13—C18—C17 | 120.9 (2) |
C6—C7—C8 | 128.74 (18) | C13—C18—H18A | 119.5 |
C7—C8—C3 | 110.45 (17) | C17—C18—H18A | 119.5 |
C1—C3—C4—C5 | −175.99 (19) | C5—C6—C10—C11 | −2.8 (4) |
C8—C3—C4—C5 | −56.9 (2) | C9—C10—C11—O3 | 178.7 (2) |
C2—C3—C4—C5 | 63.2 (2) | C6—C10—C11—O3 | −0.3 (4) |
C3—C4—C5—O1 | −142.1 (2) | C9—C10—C11—C12 | −2.9 (3) |
C3—C4—C5—C6 | 38.6 (3) | C6—C10—C11—C12 | 178.1 (2) |
O1—C5—C6—C7 | 171.1 (2) | O3—C11—C12—C15 | 1.5 (3) |
C4—C5—C6—C7 | −9.6 (3) | C10—C11—C12—C15 | −177.03 (17) |
O1—C5—C6—C10 | −6.8 (4) | O3—C11—C12—C13 | 179.7 (2) |
C4—C5—C6—C10 | 172.5 (2) | C10—C11—C12—C13 | 1.2 (3) |
C9—O2—C7—C6 | −0.1 (2) | C15—C12—C13—C18 | 0.8 (3) |
C9—O2—C7—C8 | −179.77 (17) | C11—C12—C13—C18 | −177.42 (19) |
C10—C6—C7—O2 | 0.0 (2) | C15—C12—C13—C14 | −179.75 (18) |
C5—C6—C7—O2 | −178.41 (17) | C11—C12—C13—C14 | 2.0 (3) |
C10—C6—C7—C8 | 179.67 (19) | C10—C9—C14—O4 | −177.5 (2) |
C5—C6—C7—C8 | 1.2 (3) | O2—C9—C14—O4 | 3.3 (3) |
O2—C7—C8—C3 | 159.23 (17) | C10—C9—C14—C13 | 1.8 (3) |
C6—C7—C8—C3 | −20.4 (3) | O2—C9—C14—C13 | −177.40 (17) |
C1—C3—C8—C7 | 164.09 (18) | C18—C13—C14—O4 | −4.7 (3) |
C2—C3—C8—C7 | −75.6 (2) | C12—C13—C14—O4 | 175.9 (2) |
C4—C3—C8—C7 | 44.4 (2) | C18—C13—C14—C9 | 176.00 (19) |
C7—O2—C9—C10 | 0.1 (2) | C12—C13—C14—C9 | −3.4 (3) |
C7—O2—C9—C14 | 179.43 (18) | C13—C12—C15—C16 | −0.3 (3) |
O2—C9—C10—C6 | −0.1 (2) | C11—C12—C15—C16 | 178.01 (19) |
C14—C9—C10—C6 | −179.36 (19) | C12—C15—C16—C17 | −0.7 (3) |
O2—C9—C10—C11 | −179.37 (16) | C15—C16—C17—C18 | 1.2 (4) |
C14—C9—C10—C11 | 1.4 (3) | C12—C13—C18—C17 | −0.4 (3) |
C7—C6—C10—C9 | 0.0 (2) | C14—C13—C18—C17 | −179.8 (2) |
C5—C6—C10—C9 | 178.1 (2) | C16—C17—C18—C13 | −0.6 (4) |
C7—C6—C10—C11 | 179.2 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
C16—H16A···O4i | 0.93 | 2.54 | 3.177 (3) | 126 |
Symmetry code: (i) x−1, y+1, z. |
Experimental details
Crystal data | |
Chemical formula | C18H14O4 |
Mr | 294.29 |
Crystal system, space group | Triclinic, 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) |
V (Å3) | 695.2 (2) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.25 × 0.18 × 0.16 |
Data collection | |
Diffractometer | Bruker APEX CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 2000) |
Tmin, Tmax | 0.976, 0.984 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2958, 2676, 1845 |
Rint | 0.018 |
(sin θ/λ)max (Å−1) | 0.616 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.047, 0.137, 1.08 |
No. of reflections | 2676 |
No. of parameters | 199 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.16, −0.23 |
Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
C16—H16A···O4i | 0.93 | 2.54 | 3.177 (3) | 125.7 |
Symmetry code: (i) x−1, y+1, z. |
Acknowledgements
The author thanks the Program for Young Excellent Talents in Southeast University for financial support.
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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).