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

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ISSN: 2056-9890

5,8-Di­bromo-15,18-dimeth­­oxy-2,11-di­thia­[3.3]para­cyclo­phane

aKey Laboratory of Pesticides and Chemical Biology of the Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China
*Correspondence e-mail: jgj6100449@163.com

(Received 1 July 2010; accepted 21 July 2010; online 31 July 2010)

In the title compound [systematic name: 12,15-dibromo-52,55-dimethoxy-2,7-dithia-1,5(1,4)-dibenzenaoctaphane], C18H18Br2O2S2, the dihedral angle between the aromatic rings is 0.6 (2)° and their centroid separation is 3.251 (2) Å, indicating that a trans-annular ππ interaction occurs. The dimeth­oxy and dibromo substituents are located at crossed positions because of the electronic and the steric nature of the substituents.

Related literature

For the preparation of the title compound, see: Kay & Baek (1997[Kay, K. Y. & Baek, Y. G. (1997). Chem. Ber. Rec. 130, 581-584.]); Xu et al. (2008[Xu, J. W., Wang, W. L., Lin, T. T., Sun, Z.& Lai, Y. H. (2008). Supramol. Chem. 20, 723-730.]). For paracyclo­phane and its derivatives, see: Clément et al. (2009[Clément, S., Guyard, L., Knorr, M., Däschlein, C. & Strohmann, C. (2009). Acta Cryst. E65, o528.]); Wang et al. (2006[Wang, W., Xu, J., Sun, Z., Zhang, X., Lu, Y. & Lai, Y. H. (2006). Macromolecules, 39, 7277-7285.]); Yamamoto et al. (1997[Yamamoto, M., Wu, L. P., Kuroda-Sowa, T., Maekawa, M., Suenaga, Y. & Munakata, M. (1997). Inorg. Chim. Acta, 258, 87-91.]). For studies on the benzene dimer of [2.2]paracyclo­phane, see: Ball et al. (2004[Ball, P. J., Shtoyko, T. R., Bauer, J. A. K., Oldham, W. J. & Connick, W. B. (2004). Inorg. Chem. 43, 622-632.]); Dahmen & Bräse (2002[Dahmen, S. & Bräse, S. (2002). J. Am. Chem. Soc. 124, 5940-5941.]); Rowlands (2008[Rowlands, G. J. (2008). Org. Biomol. Chem. 6, 1527-1534.]); Valentini et al. (2008[Valentini, L., Marrocchi, A., Seri, M., Mengoni, F., Meloni, F., Taticchi, A. & Kenny, J. M. (2008). Thin Solid Films. 516, 7193-7198.]). For studies of [3.3]paracyclo­phane, see: Wang et al. (2004[Wang, W., Xu, J., Lai, Y. H. & Wang, F. (2004). Macromolecules, 37, 3546-3553.]).

[Scheme 1]

Experimental

Crystal data
  • C18H18Br2O2S2

  • Mr = 490.26

  • Monoclinic, P 21 /n

  • a = 8.9576 (8) Å

  • b = 16.2291 (14) Å

  • c = 13.0251 (11) Å

  • β = 103.240 (1)°

  • V = 1843.2 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 4.63 mm−1

  • T = 298 K

  • 0.16 × 0.12 × 0.10 mm

Data collection
  • Bruker SMART CCD area-detector diffractometer

  • 12800 measured reflections

  • 4475 independent reflections

  • 2812 reflections with I > 2σ(I)

  • Rint = 0.126

Refinement
  • R[F2 > 2σ(F2)] = 0.059

  • wR(F2) = 0.151

  • S = 0.95

  • 4475 reflections

  • 219 parameters

  • H-atom parameters constrained

  • Δρmax = 1.00 e Å−3

  • Δρmin = −1.27 e Å−3

Data collection: SMART (Bruker, 1997[Bruker (1997). SMART. Bruker AXS Inc., Madison, Wiskonsin, USA.]); cell refinement: SAINT (Bruker, 1999[Bruker (1999). SAINT. Bruker AXS Inc., Madison, Wiskonsin, USA.]); data reduction: SAINT; 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Various studies on the benzene dimer of [2.2]paracyclophane have focused on the face-to-face stacking (Rowlands, 2008),it is known to play a significant role in chiral catalysis (Dahmen & Bräse, 2002), molecular electronics (Ball et al.,2004), and organic solar cells (Valentini et al.,2008). However, the [3.3]paracyclophane have received less attention (Wang et al.2004). In our research, we have synthetized a series of novel dithia[3.3]paracyclophane. The inter plane distance of the two benzene rings of 3.251Å is less than the normal packing distance of aromatic rings in organic aromatic molecules(3.4°), thus suggesting probable transannular π-π interaction.

For the preparation of the title compound, see: Kay & Baek (1997); Xu et al. (2008); for the paracyclophanes and its derivatives, see: Clément et al. (2009); Wang et al. (2006); Yamamoto et al. (1997).

Related literature top

For the preparation of the title compound, see: Kay & Baek (1997); Xu et al. (2008). For paracyclophane and its derivatives, see: Clément et al. (2009); Wang et al. (2006); Yamamoto et al. (1997). For studies on the benzene dimer of [2.2]paracyclophane, see: Ball et al. (2004); Dahmen & Bräse (2002); Rowlands (2008); Valentini et al. (2008). For studies of [3.3]paracyclophane, see: Wang et al. (2004).

Experimental top

A solution with equimolar amounts of 2,5-dibromo-1,4-bis(mercaptomethyl)benzene (3.26 g,10 mmol) and 1,4-dibromomethyl-2,5-dimethoxybenzene(3.22 g,10 mmol) in degassed THF(500 mL) was added dropwise under N2 over 12 h to a refluxing solution of potassium carbonate(6.9 g,50 mmol) in EtOH(1.5L). After an additional 2 h at the reflux temperature (353 K), the mixture was cooled and the solvent were removed. The resulting residue was treated with CH2Cl2(500 mL) and water(500 mL). The organic phase was separated, the aqueous extracted with CH2Cl2 three times. The combined organic layers was dried over Na2SO4,then the solvent was removed, and the resulting solid was chromatographed on silica gel using CH2Cl2/petroleum ether(1:1,v/v) as eluent. Colourless single crystals of the title compound suitable for X-ray diffraction were obtained by slow evaporation of a dichloromethane/n-hexane(1:30) solution over a period of 5 days.

Refinement top

Hydrogen atoms were placed in calculated positions and refined using a riding model with C—H = 0.93 - 0.97 Å and Uiso(H) = 1.2Ueq(C-H, CH2), 1.5Ueq(CH3).

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the tite compound with displacement ellipsoids drawn at the 30% probability level.
12,15-dibromo-52,55-dimethoxy-2,7-dithia-1,5(1,4)-dibenzenaoctaphane top
Crystal data top
C18H18Br2O2S2F(000) = 976
Mr = 490.26Dx = 1.767 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 3885 reflections
a = 8.9576 (8) Åθ = 2.5–26.9°
b = 16.2291 (14) ŵ = 4.63 mm1
c = 13.0251 (11) ÅT = 298 K
β = 103.240 (1)°Block, colorless
V = 1843.2 (3) Å30.16 × 0.12 × 0.10 mm
Z = 4
Data collection top
Bruker SMART CCD area detector
diffractometer
2812 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.126
Graphite monochromatorθmax = 28.3°, θmin = 2.0°
phi and ω scansh = 1111
12800 measured reflectionsk = 1921
4475 independent reflectionsl = 1517
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)] = 0.059Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.151H-atom parameters constrained
S = 0.95 w = 1/[σ2(Fo2) + (0.0753P)2]
where P = (Fo2 + 2Fc2)/3
4475 reflections(Δ/σ)max = 0.001
219 parametersΔρmax = 1.00 e Å3
0 restraintsΔρmin = 1.27 e Å3
Crystal data top
C18H18Br2O2S2V = 1843.2 (3) Å3
Mr = 490.26Z = 4
Monoclinic, P21/nMo Kα radiation
a = 8.9576 (8) ŵ = 4.63 mm1
b = 16.2291 (14) ÅT = 298 K
c = 13.0251 (11) Å0.16 × 0.12 × 0.10 mm
β = 103.240 (1)°
Data collection top
Bruker SMART CCD area detector
diffractometer
2812 reflections with I > 2σ(I)
12800 measured reflectionsRint = 0.126
4475 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0590 restraints
wR(F2) = 0.151H-atom parameters constrained
S = 0.95Δρmax = 1.00 e Å3
4475 reflectionsΔρmin = 1.27 e Å3
219 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
Br10.56512 (6)0.00221 (3)0.68306 (4)0.0672 (2)
Br21.04343 (6)0.17844 (3)0.44267 (4)0.05796 (19)
C10.9651 (5)0.0721 (2)0.6001 (3)0.0383 (9)
C20.8556 (5)0.0352 (2)0.6428 (3)0.0414 (9)
H20.88580.00670.69190.050*
C30.7037 (5)0.0569 (2)0.6166 (3)0.0421 (9)
C40.6510 (5)0.1210 (2)0.5448 (3)0.0426 (9)
C50.7568 (5)0.1535 (2)0.4937 (3)0.0419 (9)
H50.72480.19240.44080.050*
C60.9099 (5)0.1296 (2)0.5193 (3)0.0386 (9)
C71.1351 (5)0.0552 (3)0.6408 (3)0.0478 (10)
H7A1.19210.10260.62500.057*
H7B1.16300.00850.60270.057*
C81.2053 (5)0.1368 (3)0.8357 (3)0.0603 (13)
H8A1.23300.13230.91200.072*
H8B1.28650.16690.81400.072*
C91.0584 (5)0.1853 (3)0.8039 (3)0.0483 (11)
C100.9312 (5)0.1636 (3)0.8413 (3)0.0466 (10)
C110.7901 (5)0.1997 (3)0.7979 (3)0.0461 (10)
H110.70410.18420.82200.055*
C120.7759 (5)0.2590 (3)0.7186 (3)0.0423 (9)
C130.9054 (5)0.2850 (3)0.6891 (3)0.0447 (10)
C141.0460 (5)0.2476 (3)0.7292 (3)0.0480 (10)
H141.13210.26420.70610.058*
C150.6193 (5)0.2917 (3)0.6623 (4)0.0519 (11)
H15A0.62790.31410.59480.062*
H15B0.59280.33680.70350.062*
C160.4926 (5)0.1575 (3)0.5276 (4)0.0531 (11)
H16A0.41790.11320.51430.064*
H16B0.47450.19220.46540.064*
C170.8336 (7)0.0803 (4)0.9594 (4)0.0767 (16)
H17A0.79240.12760.98740.115*
H17B0.86880.04111.01490.115*
H17C0.75530.05550.90540.115*
C181.0126 (6)0.3817 (3)0.5888 (4)0.0703 (14)
H18A1.07030.40950.65030.106*
H18B0.98070.42080.53280.106*
H18C1.07560.34020.56730.106*
O10.9536 (4)0.1039 (2)0.9173 (2)0.0666 (9)
O20.8860 (4)0.34533 (19)0.6119 (2)0.0584 (8)
S11.19297 (14)0.03433 (8)0.77929 (9)0.0601 (3)
S20.46307 (13)0.21831 (8)0.63885 (10)0.0559 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0566 (3)0.0782 (4)0.0670 (4)0.0235 (2)0.0142 (3)0.0087 (2)
Br20.0558 (3)0.0679 (3)0.0542 (3)0.0029 (2)0.0209 (2)0.0073 (2)
C10.038 (2)0.041 (2)0.0332 (19)0.0023 (16)0.0015 (15)0.0064 (16)
C20.046 (2)0.039 (2)0.036 (2)0.0006 (18)0.0028 (17)0.0016 (17)
C30.043 (2)0.046 (2)0.036 (2)0.0103 (18)0.0058 (17)0.0035 (17)
C40.039 (2)0.048 (2)0.035 (2)0.0046 (18)0.0025 (16)0.0061 (17)
C50.045 (2)0.050 (2)0.0287 (19)0.0017 (18)0.0036 (16)0.0002 (17)
C60.041 (2)0.045 (2)0.0292 (18)0.0044 (17)0.0055 (16)0.0023 (16)
C70.043 (2)0.059 (3)0.040 (2)0.005 (2)0.0048 (18)0.0066 (19)
C80.041 (3)0.097 (4)0.036 (2)0.002 (2)0.0063 (18)0.010 (2)
C90.036 (2)0.072 (3)0.032 (2)0.005 (2)0.0033 (17)0.018 (2)
C100.049 (3)0.064 (3)0.0253 (19)0.000 (2)0.0041 (17)0.0072 (18)
C110.037 (2)0.064 (3)0.039 (2)0.0033 (19)0.0114 (17)0.0076 (19)
C120.036 (2)0.051 (2)0.038 (2)0.0044 (18)0.0059 (16)0.0099 (18)
C130.043 (2)0.054 (2)0.034 (2)0.0112 (19)0.0024 (17)0.0136 (18)
C140.037 (2)0.068 (3)0.037 (2)0.011 (2)0.0034 (16)0.018 (2)
C150.040 (2)0.059 (3)0.056 (3)0.003 (2)0.010 (2)0.002 (2)
C160.032 (2)0.072 (3)0.050 (2)0.003 (2)0.0010 (18)0.001 (2)
C170.077 (4)0.100 (4)0.054 (3)0.002 (3)0.017 (3)0.027 (3)
C180.068 (3)0.069 (3)0.072 (3)0.023 (3)0.014 (3)0.004 (3)
O10.055 (2)0.102 (3)0.0419 (17)0.0117 (19)0.0104 (15)0.0129 (17)
O20.056 (2)0.0589 (18)0.058 (2)0.0108 (16)0.0077 (15)0.0047 (15)
S10.0459 (7)0.0797 (8)0.0499 (7)0.0193 (6)0.0010 (5)0.0161 (6)
S20.0312 (6)0.0714 (8)0.0654 (8)0.0008 (5)0.0113 (5)0.0028 (6)
Geometric parameters (Å, º) top
Br1—C31.889 (4)C10—C111.390 (6)
Br2—C61.898 (4)C11—C121.397 (6)
C1—C21.372 (6)C11—H110.9300
C1—C61.408 (5)C12—C131.369 (6)
C1—C71.518 (6)C12—C151.521 (6)
C2—C31.371 (6)C13—O21.386 (5)
C2—H20.9300C13—C141.388 (6)
C3—C41.407 (5)C14—H140.9300
C4—C51.382 (6)C15—S21.809 (4)
C4—C161.506 (6)C15—H15A0.9700
C5—C61.390 (6)C15—H15B0.9700
C5—H50.9300C16—S21.822 (5)
C7—S11.792 (4)C16—H16A0.9700
C7—H7A0.9700C16—H16B0.9700
C7—H7B0.9700C17—O11.369 (6)
C8—C91.508 (6)C17—H17A0.9600
C8—S11.812 (5)C17—H17B0.9600
C8—H8A0.9700C17—H17C0.9600
C8—H8B0.9700C18—O21.372 (6)
C9—C101.384 (6)C18—H18A0.9600
C9—C141.389 (6)C18—H18B0.9600
C10—O11.368 (5)C18—H18C0.9600
C2—C1—C6115.5 (4)C12—C11—H11119.6
C2—C1—C7122.2 (4)C13—C12—C11118.7 (4)
C6—C1—C7122.2 (4)C13—C12—C15120.3 (4)
C3—C2—C1123.3 (4)C11—C12—C15120.9 (4)
C3—C2—H2118.4C12—C13—O2116.6 (4)
C1—C2—H2118.4C12—C13—C14120.9 (4)
C2—C3—C4121.2 (4)O2—C13—C14122.3 (4)
C2—C3—Br1119.0 (3)C13—C14—C9120.1 (4)
C4—C3—Br1119.8 (3)C13—C14—H14119.9
C5—C4—C3116.1 (4)C9—C14—H14119.9
C5—C4—C16120.4 (4)C12—C15—S2116.4 (3)
C3—C4—C16123.4 (4)C12—C15—H15A108.2
C4—C5—C6121.7 (4)S2—C15—H15A108.2
C4—C5—H5119.1C12—C15—H15B108.2
C6—C5—H5119.1S2—C15—H15B108.2
C5—C6—C1121.5 (4)H15A—C15—H15B107.3
C5—C6—Br2117.6 (3)C4—C16—S2113.5 (3)
C1—C6—Br2120.9 (3)C4—C16—H16A108.9
C1—C7—S1114.9 (3)S2—C16—H16A108.9
C1—C7—H7A108.5C4—C16—H16B108.9
S1—C7—H7A108.5S2—C16—H16B108.9
C1—C7—H7B108.5H16A—C16—H16B107.7
S1—C7—H7B108.5O1—C17—H17A109.5
H7A—C7—H7B107.5O1—C17—H17B109.5
C9—C8—S1113.5 (3)H17A—C17—H17B109.5
C9—C8—H8A108.9O1—C17—H17C109.5
S1—C8—H8A108.9H17A—C17—H17C109.5
C9—C8—H8B108.9H17B—C17—H17C109.5
S1—C8—H8B108.9O2—C18—H18A109.5
H8A—C8—H8B107.7O2—C18—H18B109.5
C10—C9—C14119.4 (4)H18A—C18—H18B109.5
C10—C9—C8120.5 (4)O2—C18—H18C109.5
C14—C9—C8119.8 (4)H18A—C18—H18C109.5
O1—C10—C9116.0 (4)H18B—C18—H18C109.5
O1—C10—C11124.2 (4)C10—O1—C17119.3 (4)
C9—C10—C11119.7 (4)C18—O2—C13119.4 (4)
C10—C11—C12120.7 (4)C7—S1—C8102.2 (2)
C10—C11—H11119.6C15—S2—C16104.1 (2)
C6—C1—C2—C35.6 (6)O1—C10—C11—C12178.4 (4)
C7—C1—C2—C3171.5 (4)C9—C10—C11—C121.5 (6)
C1—C2—C3—C41.6 (6)C10—C11—C12—C134.2 (6)
C1—C2—C3—Br1179.0 (3)C10—C11—C12—C15173.1 (4)
C2—C3—C4—C57.4 (6)C11—C12—C13—O2178.4 (4)
Br1—C3—C4—C5175.2 (3)C15—C12—C13—O24.2 (5)
C2—C3—C4—C16168.8 (4)C11—C12—C13—C146.4 (6)
Br1—C3—C4—C168.6 (5)C15—C12—C13—C14171.0 (4)
C3—C4—C5—C66.0 (6)C12—C13—C14—C92.8 (6)
C16—C4—C5—C6170.4 (4)O2—C13—C14—C9177.7 (3)
C4—C5—C6—C11.2 (6)C10—C9—C14—C133.0 (6)
C4—C5—C6—Br2179.7 (3)C8—C9—C14—C13171.4 (4)
C2—C1—C6—C57.0 (5)C13—C12—C15—S2141.2 (3)
C7—C1—C6—C5170.2 (4)C11—C12—C15—S236.0 (5)
C2—C1—C6—Br2174.0 (3)C5—C4—C16—S2105.9 (4)
C7—C1—C6—Br28.8 (5)C3—C4—C16—S270.2 (5)
C2—C1—C7—S132.5 (5)C9—C10—O1—C17178.9 (4)
C6—C1—C7—S1144.4 (3)C11—C10—O1—C174.1 (7)
S1—C8—C9—C1069.9 (5)C12—C13—O2—C18171.4 (4)
S1—C8—C9—C14104.4 (4)C14—C13—O2—C1813.5 (6)
C14—C9—C10—O1177.8 (4)C1—C7—S1—C880.3 (4)
C8—C9—C10—O17.9 (6)C9—C8—S1—C756.6 (4)
C14—C9—C10—C115.1 (6)C12—C15—S2—C1676.7 (4)
C8—C9—C10—C11169.2 (4)C4—C16—S2—C1553.5 (4)

Experimental details

Crystal data
Chemical formulaC18H18Br2O2S2
Mr490.26
Crystal system, space groupMonoclinic, P21/n
Temperature (K)298
a, b, c (Å)8.9576 (8), 16.2291 (14), 13.0251 (11)
β (°) 103.240 (1)
V3)1843.2 (3)
Z4
Radiation typeMo Kα
µ (mm1)4.63
Crystal size (mm)0.16 × 0.12 × 0.10
Data collection
DiffractometerBruker SMART CCD area detector
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
12800, 4475, 2812
Rint0.126
(sin θ/λ)max1)0.666
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.059, 0.151, 0.95
No. of reflections4475
No. of parameters219
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)1.00, 1.27

Computer programs: SMART (Bruker, 1997), SAINT (Bruker, 1999), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

The authors thank Professor Sheng-Hua Liu for technical assistance with the structure analysis and Dr Xiang-Gao Meng for the data collection.

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