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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 64| Part 10| October 2008| Page o1929
doi:10.1107/S1600536808028432

3-Allyl-2-hydr­­oxy-5,6,8-tri­meth­oxy­naphthalene-1,4-dione

Dominea C. K. Rathwell,a Kit Y. Tsang,a Ka Wai Choi,a Peter D. W. Boyda and Margaret A. Brimblea*

aDepartment of Chemistry, University of Auckland, Private Bag 92019, Auckland, New Zealand
*Correspondence e-mail: m.brimble@auckland.ac.nz

(Received 2 September 2008; accepted 5 September 2008; online 13 September 2008)

In the crystal structure of the title compound, C16H16O6, a pair of naphthoquinone rings are linked via O—H⋯O—C hydrogen bonds in a nearly orthogonal arrangement. This dimeric unit is linked to a neighbouring dimer by π–π stacking inter­actions between the naphthoquinone rings, where the distance between the mean plane of the naphtoquinone backbones is 3.468 Å, and O—H⋯O—C hydrogen bonds.

Related literature

For details of the synthesis, see: Brimble et al. (2008[Brimble, M. A., Rathwell, D. C. K. & Tsang, K. Y. (2008). In preparation.]). For related syntheses, see: Reissig et al. (2006[Reissig, H. U., Sörgel, S. & Azap, C. (2006). Eur. J. Org. Chem. pp. 4405-4418.]); Kozlowski et al. (2008[Kozlowski, M. C., Lowell, A. N. & Fennie, M. W. (2008). J. Org. Chem. 73, 1911-1918.]). For the biological activity of rubromycins, see: Brockmann et al. (1953[Brockmann, H. & Renneberg, K. H. (1953). Naturwissenschaften, 40, 59-60.], 1966[Brockmann, H., Lenk, W., Schwantje, A. & Zeeck, A. (1966). Tetrahedron Lett. 30, 3525-3530.]).

[Scheme 1]

Experimental

Crystal data

  • C16H16O6

  • Mr = 304.29

  • Orthorhombic, P 21 21 21

  • a = 4.68110 (10) Å

  • b = 12.6577 (3) Å

  • c = 23.3392 (5) Å

  • V = 1382.89 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 89 (2) K

  • 0.28 × 0.09 × 0.06 mm
Data collection

  • Bruker SMART diffractometer with APEXII CCD detector

  • Absorption correction: none

  • 14372 measured reflections

  • 1914 independent reflections

  • 1415 reflections with I > 2σ(I)

  • Rint = 0.031
Refinement

  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.085

  • S = 1.09

  • 1914 reflections

  • 200 parameters

  • H-atom parameters constrained

  • Δρmax = 0.22 e Å−3

  • Δρmin = −0.28 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O16—H16⋯O12 0.82 2.14 2.612 (2) 117
O16—H16⋯O12i 0.82 2.05 2.777 (2) 148
O16—H16⋯O19i 0.82 2.40 2.926 (2) 122
Symmetry code: (i) [x-{\script{1\over 2}}, -y+{\script{1\over 2}}, -z].

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2; data reduction: SAINT (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); 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: ORTEPIII (Burnett & Johnson, 1996[Burnett, M. N. & Johnson, C. K. (1996). ORTEPIII. Report ORNL-6895. Oak Ridge National Laboratory, Tennessee, USA.]) and Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and publCIF (Westrip, 2008[Westrip, S. P. (2008). publCIF. In preparation.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808028432/ng2489sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808028432/ng2489Isup2.hkl

checkCIF report


Comment top

The rubromycins are a structurally related family of antibiotics that exhibit a wide range of biological activity (Brockmann et al., 1953, 1966). The common structural features of this family of antibiotics consists of a naphthoquinone and an isocoumarin ring linked through a bis-benzannelated-5,6-spiroacetal ring system. Our recent synthetic efforts have focused on the synthesis of the naphthoquinone units of the rubromycins and its regioisomeric counterpart. The tandem Ullman coupling–Claisen rearrangement has been successfully employed to access the regioisomeric naphthoquinones in which the title compound was isolated as a minor isomer. The newly introduced hydroxyl and allyl groups were established by X-ray crystallography to be at C8 and C9, respectively (Fig. 1). The crystal packing is dominated by intermolecular hydrogen bonds and π–π interactions (Table 1, Fig. 2). Further detailed analysis revealed that a pair of naphthoquinone rings are linked via O—H···O—C hydrogen bonding in a near orthogonal arrangement with respect to each other. This dimeric unit stacks on top of a neighbouring dimer with π–π stacking interactions between the naphthoquinone rings and O—H···O—C hydrogen bonding (Table 1, Fig. 2).

Related literature top

For details of the synthesis, see: Brimble et al. (2008). For related literature, see: Reißig et al. (2006); Kozlowski et al. (2008); Brockmann et al. (1953, 1966).

Experimental top

A mixture of 2-bromo-5,7,8-trimethoxynaphthalene-1,4-dione (500 mg, 1.6 mmol), allyl alcohol (0.5 ml, 10 mmol), copper iodide (46 mg, 0.14 mmol) and caesium carbonate (940 mg, 2.9 mmol) in toluene (3 ml) was heated at 320 K under a nitrogen atmosphere in a sealed tube for 30 min. After allowing the mixture to cool to room temperature, the brownish mixture was filtered through a plug of Celite. The brown filtrate was then irradiated with microwave at 410 K (60 W) for 180 min in a sealed tube (10 ml pressure-rated reaction vial) in a self-tuning single mode irradiating synthesizer (CEM Discover LabMate microwave synthesizer). The resulting solution was then concentrated in vacuo to afford a brown residue. Purification of the crude residue by flash column chromatography using ethyl acetate–hexane (2:8) with gradient elution to neat ethyl acetate afforded the title compound (116 mg, 24%) as a yellow solid. Recrystallization from acetonitrile afforded yellow needles suitable for X-ray diffraction. m.p. 427–431 K

Refinement top

Hydrogen atoms were placed in calculated positions and refined using the riding model (C—H 0.93–0.97 Å), with Uiso(H) = 1.5 times Ueq(O) and Uiso(H) = 1.2 or 1.5 times Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: APEX2 (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996) and Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia, 1999) and publCIF (Westrip, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure and the atom numbering scheme of the title compound. Ellipsoids are drawn at 50% probability level for non-H atoms.
[Figure 2] Fig. 2. Molecular packing of the title naphthoquinone, viewed along the b axis. (···, in green) hydrogen bond; (|||, in blue) π–π interaction. The H atoms not involved in hydrogen bonding have been omitted.
3-Allyl-2-hydroxy-5,6,8-trimethoxynaphthalene-1,4-dione top
Crystal data top
C16H16O6Dx = 1.462 Mg m−3
Mr = 304.29Melting point: 429(2) K
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
a = 4.6811 (1) ÅCell parameters from 3251 reflections
b = 12.6577 (3) Åθ = 1.8–27.9°
c = 23.3392 (5) ŵ = 0.11 mm−1
V = 1382.89 (5) Å3T = 89 K
Z = 4Needle, yellow
F(000) = 6400.28 × 0.09 × 0.06 mm
Data collection top
Bruker SMART
diffractometer with APEXII CCD detector		1415 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.031
Graphite monochromatorθmax = 27.9°, θmin = 1.8°
ω scansh = −6→4
14372 measured reflectionsk = −16→16
1914 independent reflectionsl = −30→30
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)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.085H-atom parameters constrained
S = 1.09 w = 1/[σ2(Fo2) + (0.0367P)2 + 0.1796P]
where P = (Fo2 + 2Fc2)/3
1914 reflections(Δ/σ)max < 0.001
200 parametersΔρmax = 0.22 e Å−3
0 restraintsΔρmin = −0.28 e Å−3
Crystal data top
C16H16O6V = 1382.89 (5) Å3
Mr = 304.29Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 4.6811 (1) ŵ = 0.11 mm−1
b = 12.6577 (3) ÅT = 89 K
c = 23.3392 (5) Å0.28 × 0.09 × 0.06 mm
Data collection top
Bruker SMART
diffractometer with APEXII CCD detector		1415 reflections with I > 2σ(I)
14372 measured reflectionsRint = 0.031
1914 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.085H-atom parameters constrained
S = 1.09Δρmax = 0.22 e Å−3
1914 reflectionsΔρmin = −0.28 e Å−3
200 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
O16−0.4858 (4)0.07396 (13)0.01234 (6)0.0192 (4)
H16−0.47510.1330−0.00200.029*
O11−0.1507 (4)−0.09214 (12)0.17755 (7)0.0183 (4)
O170.2562 (4)−0.00627 (12)0.24216 (6)0.0150 (4)
O190.2115 (4)0.33797 (12)0.09662 (7)0.0174 (4)
O12−0.1853 (4)0.24133 (13)0.03789 (6)0.0164 (4)
O180.5482 (4)0.16101 (12)0.26649 (6)0.0162 (4)
C50.0492 (6)0.07747 (18)0.15754 (9)0.0125 (6)
C40.0441 (6)0.16715 (18)0.12052 (9)0.0129 (5)
C20.3969 (6)0.25329 (19)0.18127 (10)0.0141 (6)
H20.51400.31080.18910.017*
C60.2263 (6)0.07808 (18)0.20552 (9)0.0129 (6)
C30.2219 (6)0.25382 (18)0.13284 (9)0.0134 (6)
C8−0.3187 (6)0.06946 (19)0.05919 (9)0.0148 (6)
C210.7270 (6)0.24990 (19)0.28100 (10)0.0180 (6)
H21A0.82370.23600.31650.027*
H21B0.61100.31200.28500.027*
H21C0.86530.26080.25120.027*
C9−0.3109 (6)−0.01717 (18)0.09232 (9)0.0135 (6)
C10.3956 (6)0.16712 (19)0.21750 (9)0.0130 (6)
C7−0.1488 (6)0.16625 (19)0.07100 (9)0.0141 (6)
C200.4222 (6)0.41995 (19)0.10271 (10)0.0196 (6)
H20A0.38890.47380.07450.029*
H20B0.60930.39060.09730.029*
H20C0.40890.45020.14030.029*
C10−0.1373 (6)−0.01652 (19)0.14485 (9)0.0134 (6)
C14−0.2956 (7)−0.2026 (2)0.05618 (11)0.0214 (7)
H14−0.2007−0.19040.02180.026*
C220.0511 (6)−0.00647 (18)0.28793 (9)0.0175 (6)
H22A0.0825−0.06690.31200.026*
H22B−0.1383−0.00950.27220.026*
H22C0.07190.05680.31020.026*
C15−0.2583 (7)−0.2953 (2)0.08090 (11)0.0288 (8)
H15A−0.3497−0.31040.11530.035*
H15B−0.1405−0.34550.06390.035*
C13−0.4799 (6)−0.11548 (17)0.07933 (10)0.0155 (6)
H13A−0.5731−0.13960.11410.019*
H13B−0.6273−0.09880.05160.019*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O160.0252 (12)0.0179 (9)0.0146 (8)−0.0020 (10)−0.0054 (9)0.0036 (7)
O110.0207 (11)0.0155 (9)0.0185 (8)−0.0029 (9)−0.0019 (8)0.0038 (7)
O170.0168 (10)0.0133 (8)0.0148 (8)0.0008 (9)0.0016 (9)0.0044 (7)
O190.0200 (11)0.0132 (8)0.0190 (9)−0.0049 (9)−0.0026 (9)0.0042 (7)
O120.0164 (10)0.0170 (9)0.0157 (8)−0.0003 (9)0.0003 (9)0.0024 (7)
O180.0178 (10)0.0136 (8)0.0171 (8)−0.0029 (9)−0.0039 (9)0.0014 (7)
C50.0116 (15)0.0122 (11)0.0136 (11)0.0032 (12)0.0041 (12)−0.0012 (9)
C40.0125 (14)0.0135 (11)0.0127 (11)−0.0004 (12)0.0021 (12)0.0010 (9)
C20.0120 (15)0.0130 (12)0.0172 (12)−0.0016 (12)0.0018 (12)−0.0018 (10)
C60.0130 (15)0.0137 (12)0.0121 (11)0.0032 (13)0.0011 (12)0.0010 (9)
C30.0133 (15)0.0118 (12)0.0149 (11)0.0030 (13)0.0032 (13)0.0023 (9)
C80.0130 (15)0.0191 (13)0.0122 (11)0.0008 (13)0.0000 (12)−0.0005 (10)
C210.0190 (17)0.0171 (13)0.0179 (12)−0.0043 (14)−0.0045 (14)−0.0024 (10)
C90.0118 (15)0.0152 (12)0.0136 (11)−0.0009 (12)−0.0013 (12)−0.0013 (10)
C10.0102 (15)0.0166 (12)0.0120 (11)0.0051 (12)0.0004 (11)−0.0014 (10)
C70.0135 (15)0.0149 (12)0.0140 (11)0.0009 (13)0.0056 (12)0.0011 (10)
C200.0220 (17)0.0168 (13)0.0198 (12)−0.0052 (13)0.0005 (13)−0.0011 (11)
C100.0118 (15)0.0139 (12)0.0144 (11)0.0033 (11)0.0039 (12)0.0001 (10)
C140.0233 (18)0.0216 (14)0.0193 (12)−0.0058 (14)−0.0010 (14)−0.0031 (10)
C220.0211 (15)0.0171 (13)0.0142 (11)−0.0003 (13)0.0024 (13)0.0034 (10)
C150.036 (2)0.0226 (15)0.0275 (14)0.0036 (16)0.0000 (17)−0.0033 (12)
C130.0155 (16)0.0153 (12)0.0156 (11)−0.0041 (12)−0.0031 (14)0.0027 (10)
Geometric parameters (Å, º) top
O16—C81.346 (3)C8—C71.486 (3)
O16—H160.8200C21—H21A0.9600
O11—C101.226 (3)C21—H21B0.9600
O17—C61.375 (3)C21—H21C0.9600
O17—C221.436 (3)C9—C101.471 (3)
O19—C31.361 (3)C9—C131.505 (3)
O19—C201.439 (3)C20—H20A0.9600
O12—C71.237 (3)C20—H20B0.9600
O18—C11.350 (3)C20—H20C0.9600
O18—C211.443 (3)C14—C151.318 (4)
C5—C61.394 (3)C14—C131.501 (4)
C5—C41.427 (3)C14—H140.9300
C5—C101.505 (3)C22—H22A0.9600
C4—C31.407 (3)C22—H22B0.9600
C4—C71.467 (3)C22—H22C0.9600
C2—C11.380 (3)C15—H15A0.9300
C2—C31.396 (3)C15—H15B0.9300
C2—H20.9300C13—H13A0.9700
C6—C11.406 (3)C13—H13B0.9700
C8—C91.342 (3)
C8—O16—H16109.5O18—C1—C6114.9 (2)
C6—O17—C22113.32 (18)C2—C1—C6120.9 (2)
C3—O19—C20118.60 (19)O12—C7—C4124.8 (2)
C1—O18—C21117.46 (18)O12—C7—C8116.3 (2)
C6—C5—C4119.5 (2)C4—C7—C8118.8 (2)
C6—C5—C10120.5 (2)O19—C20—H20A109.5
C4—C5—C10120.0 (2)O19—C20—H20B109.5
C3—C4—C5119.1 (2)H20A—C20—H20B109.5
C3—C4—C7122.1 (2)O19—C20—H20C109.5
C5—C4—C7118.8 (2)H20A—C20—H20C109.5
C1—C2—C3119.8 (2)H20B—C20—H20C109.5
C1—C2—H2120.1O11—C10—C9119.1 (2)
C3—C2—H2120.1O11—C10—C5121.6 (2)
O17—C6—C5123.8 (2)C9—C10—C5119.3 (2)
O17—C6—C1116.2 (2)C15—C14—C13124.9 (3)
C5—C6—C1120.0 (2)C15—C14—H14117.5
O19—C3—C2121.9 (2)C13—C14—H14117.5
O19—C3—C4117.5 (2)O17—C22—H22A109.5
C2—C3—C4120.6 (2)O17—C22—H22B109.5
C9—C8—O16121.2 (2)H22A—C22—H22B109.5
C9—C8—C7123.5 (2)O17—C22—H22C109.5
O16—C8—C7115.26 (19)H22A—C22—H22C109.5
O18—C21—H21A109.5H22B—C22—H22C109.5
O18—C21—H21B109.5C14—C15—H15A120.0
H21A—C21—H21B109.5C14—C15—H15B120.0
O18—C21—H21C109.5H15A—C15—H15B120.0
H21A—C21—H21C109.5C14—C13—C9112.2 (2)
H21B—C21—H21C109.5C14—C13—H13A109.2
C8—C9—C10119.4 (2)C9—C13—H13A109.2
C8—C9—C13123.0 (2)C14—C13—H13B109.2
C10—C9—C13117.6 (2)C9—C13—H13B109.2
O18—C1—C2124.2 (2)H13A—C13—H13B107.9
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O16—H16···O120.822.142.612 (2)117
O16—H16···O12i0.822.052.777 (2)148
O16—H16···O19i0.822.402.926 (2)122
Symmetry code: (i) x−1/2, −y+1/2, −z.

Experimental details

Crystal data
Chemical formulaC16H16O6
Mr304.29
Crystal system, space groupOrthorhombic, P212121
Temperature (K)89
a, b, c (Å)4.6811 (1), 12.6577 (3), 23.3392 (5)
V (Å3)1382.89 (5)
Z4
Radiation typeMo Kα
µ (mm−1)0.11
Crystal size (mm)0.28 × 0.09 × 0.06
Data collection
DiffractometerBruker SMART
diffractometer with APEXII CCD detector
Absorption correction–
No. of measured, independent and
observed [I > 2σ(I)] reflections		14372, 1914, 1415
Rint0.031
(sin θ/λ)max (Å−1)0.658
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.085, 1.09
No. of reflections1914
No. of parameters200
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.22, −0.28

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996) and Mercury (Macrae et al., 2006), WinGX (Farrugia, 1999) and publCIF (Westrip, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O16—H16···O120.822.142.612 (2)116.5
O16—H16···O12i0.822.052.777 (2)147.6
O16—H16···O19i0.822.402.926 (2)122.4
Symmetry code: (i) x−1/2, −y+1/2, −z.
 

Acknowledgements

The authors thank Tania Groutso for her help with the data collection and the New Zealand Tertiary Education Commission for the award of Bright Future Top Achiever Doctoral Scholarships (DCKR and KYT).

References

First citationBrimble, M. A., Rathwell, D. C. K. & Tsang, K. Y. (2008). In preparation.  Google Scholar
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ISSN: 2056-9890
Volume 64| Part 10| October 2008| Page o1929
doi:10.1107/S1600536808028432
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