Related literature {#sec1}
==================

For a related structure, see: Bak *et al.* (1961[@bb1]).

Experimental {#sec2}
============

 {#sec2.1}

### Crystal data {#sec2.1.1}

C~18~H~8~F~6~N~2~O~4~S*M* *~r~* = 462.32Orthorhombic,*a* = 8.1572 (3) Å*b* = 17.6371 (6) Å*c* = 24.4150 (8) Å*V* = 3512.6 (2) Å^3^*Z* = 8Mo *K*α radiationμ = 0.28 mm^−1^*T* = 100 K0.4 × 0.36 × 0.1 mm

### Data collection {#sec2.1.2}

Bruker SMART CCD area-detector diffractometerAbsorption correction: multi-scan (*SADABS*; Bruker, 2001[@bb2]) *T* ~min~ = 0.895, *T* ~max~ = 0.97322650 measured reflections3098 independent reflections1888 reflections with *I* \> 2σ(*I*)*R* ~int~ = 0.058

### Refinement {#sec2.1.3}

*R*\[*F* ^2^ \> 2σ(*F* ^2^)\] = 0.030*wR*(*F* ^2^) = 0.053*S* = 0.803098 reflections281 parametersH-atom parameters constrainedΔρ~max~ = 0.29 e Å^−3^Δρ~min~ = −0.28 e Å^−3^

 {#d5e397}

Data collection: *SMART* (Bruker, 2001[@bb2]); cell refinement: *SAINT* (Bruker, 2001[@bb2]); data reduction: *SAINT*; program(s) used to solve structure: *SHELXS97* (Sheldrick, 2008[@bb5]); program(s) used to refine structure: *SHELXL97* (Sheldrick, 2008[@bb5]); molecular graphics: *ORTEP-3 for Windows* (Farrugia, 1997[@bb3]); software used to prepare material for publication: *WinGX* (Farrugia, 1999[@bb4]).

Supplementary Material
======================

Crystal structure: contains datablocks global, I. DOI: [10.1107/S1600536809020443/xu2528sup1.cif](http://dx.doi.org/10.1107/S1600536809020443/xu2528sup1.cif)

Structure factors: contains datablocks I. DOI: [10.1107/S1600536809020443/xu2528Isup2.hkl](http://dx.doi.org/10.1107/S1600536809020443/xu2528Isup2.hkl)

Additional supplementary materials: [crystallographic information](http://scripts.iucr.org/cgi-bin/sendsupfiles?xu2528&file=xu2528sup0.html&mime=text/html); [3D view](http://scripts.iucr.org/cgi-bin/sendcif?xu2528sup1&Qmime=cif); [checkCIF report](http://scripts.iucr.org/cgi-bin/paper?xu2528&checkcif=yes)

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: [XU2528](http://scripts.iucr.org/cgi-bin/sendsup?xu2528)).

This work was partially supported by the Institute of Chemistry, Academia Sinica, and Cardinal Tien College of Healthcare and Management.

Comment
=======

The title compound, (I), has been shown to be an excellent precursor for the production of low band gap conjugated polymers and organic light-emitting devices *etc*. As indicated in Scheme 2, standard procedures were administrated to synthesize in high yield. The molecular structure is shown in Fig. 1. The double bonds and C---C single bond of (I) are slightly shorter than those of the parent thiophene, while the S---C single bond is slightly elongated (Bak *et al.*, 1961). The dihedral angles between the thiophene (S/C1--C4) and benzene rings (C11--C16 and C21--C26) are 35.90 (8) and 61.94 (8)°, respectively, and that between the two benzene rings is 40.18 (8)°. The two nitro groups are oriented at the thiophene ring with the dihedral angles of 53.66 (10) and 31.63 (10)°, respectively. Intermolecular weak C---H···O hydrogen bonding helps to stabilize the crystal structure (Table 1).

Experimental {#experimental}
============

The compound was synthesized by the following procedure. A two-necked round-bottomed flask was charged with Pd(PPh~3~)~4~ (280 mg), tributyl(4-(trifluoromethyl)phenyl)stannane (3.26 g, 7.5 mmol), 2,5-dibromo-3,4-dinitrothiophene (1.00 g, 3.0 mmol) and DMF (20 ml), and the reaction mixture stirred under nitrogen and heated at 343 K for 48 h. After cooling, the mixture was diluted with diethyl ether and the organic phase was washed with water and brine. After drying over anhydrous MgSO~4~ and removing the volatiles, the residue was purified by column chromatography using CH~2~Cl~2~/n-hexane as eluent, followed by recrystallization from CH~2~Cl~2~ and hexane to yield 0.7 g (50%) of (I) as a white solid. Crystals suitable for X-ray diffraction were grown from a CH~2~Cl~2~ solution layered with hexane at room temperature.

Refinement {#refinement}
==========

H atoms were located geometrically and treated as riding atoms, with C---H = 0.93 Å, and with *U*~iso~(H) = 1.2*U*~eq~(C).

Figures
=======

![A molecular structure of (I) with 30% probability displacement ellipsoids, showing the atom-numbering scheme employed. H atoms are shown as small spheres of the arbitrary radii.](e-65-o1469-fig1){#Fap1}

![The formation of the title compound.](e-65-o1469-fig2){#Fap2}

Crystal data {#tablewrapcrystaldatalong}
============

  ------------------------- ---------------------------------------
  C~18~H~8~F~6~N~2~O~4~S    *F*(000) = 1856
  *M~r~* = 462.32           *D*~x~ = 1.748 Mg m^−3^
  Orthorhombic, *Pbca*      Mo *K*α radiation, λ = 0.71073 Å
  Hall symbol: -P 2ac 2ab   Cell parameters from 3689 reflections
  *a* = 8.1572 (3) Å        θ = 2.3--21.2°
  *b* = 17.6371 (6) Å       µ = 0.28 mm^−1^
  *c* = 24.4150 (8) Å       *T* = 100 K
  *V* = 3512.6 (2) Å^3^     Plate, colourless
  *Z* = 8                   0.4 × 0.36 × 0.1 mm
  ------------------------- ---------------------------------------

Data collection {#tablewrapdatacollectionlong}
===============

  ------------------------------------------------------------ --------------------------------------
  Bruker SMART CCD area-detector diffractometer                3098 independent reflections
  Radiation source: fine-focus sealed tube                     1888 reflections with *I* \> 2σ(*I*)
  graphite                                                     *R*~int~ = 0.058
  ω and φ scans                                                θ~max~ = 25.0°, θ~min~ = 1.7°
  Absorption correction: multi-scan (*SADABS*; Bruker, 2001)   *h* = −8→9
  *T*~min~ = 0.895, *T*~max~ = 0.973                           *k* = −20→20
  22650 measured reflections                                   *l* = −29→29
  ------------------------------------------------------------ --------------------------------------

Refinement {#tablewraprefinementdatalong}
==========

  ---------------------------------------------------------------- ----------------------------------------------------------------------------------------------------
  Refinement on *F*^2^                                             Secondary atom site location: difference Fourier map
  Least-squares matrix: full                                       Hydrogen site location: inferred from neighbouring sites
  *R*\[*F*^2^ \> 2σ(*F*^2^)\] = 0.030                              H-atom parameters constrained
  *wR*(*F*^2^) = 0.053                                             *w* = 1/\[σ^2^(*F*~o~^2^) + (0.0222*P*)^2^\] where *P* = (*F*~o~^2^ + 2*F*~c~^2^)/3
  *S* = 0.80                                                       (Δ/σ)~max~ \< 0.001
  3098 reflections                                                 Δρ~max~ = 0.28 e Å^−3^
  281 parameters                                                   Δρ~min~ = −0.28 e Å^−3^
  0 restraints                                                     Extinction correction: *SHELXL97* (Sheldrick, 2008), Fc^\*^=kFc\[1+0.001xFc^2^λ^3^/sin(2θ)\]^-1/4^
  Primary atom site location: structure-invariant direct methods   Extinction coefficient: 0.00042 (7)
  ---------------------------------------------------------------- ----------------------------------------------------------------------------------------------------

Special details {#specialdetails}
===============

  -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  Experimental. ^1^H NMR (CDCl~3~): 7.77 (d, J = 8.2, 4H), 7.64 (d, J = 8.2, 4H). FAB MS (m/e): 462 (*M*^+^). Analysis calculated for C~18~H~8~F~6~N~2~O~4~S: C 46.76, H 1.74, N 6.06%; found: C 46.80, H 1.88, N 5.79%.
  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 *F*^2^ against ALL reflections. The weighted *R*-factor *wR* and goodness of fit *S* are based on *F*^2^, conventional *R*-factors *R* are based on *F*, with *F* set to zero for negative *F*^2^. The threshold expression of *F*^2^ \> σ(*F*^2^) is used only for calculating *R*-factors(gt) *etc*. and is not relevant to the choice of reflections for refinement. *R*-factors based on *F*^2^ 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 (Å^2^) {#tablewrapcoords}
==================================================================================================

  ----- -------------- --------------- ------------- -------------------- --
        *x*            *y*             *z*           *U*~iso~\*/*U*~eq~   
  S     0.49028 (6)    0.16607 (3)     0.10370 (2)   0.01968 (14)         
  F1    0.35605 (13)   0.58240 (6)     0.14011 (4)   0.0308 (3)           
  F2    0.55441 (13)   0.58514 (6)     0.08266 (5)   0.0355 (3)           
  F3    0.31448 (13)   0.55311 (6)     0.05612 (4)   0.0317 (3)           
  F4    0.39559 (15)   −0.25593 (7)    0.10705 (5)   0.0436 (4)           
  F5    0.59498 (14)   −0.24370 (7)    0.05129 (5)   0.0414 (4)           
  F6    0.35364 (14)   −0.21365 (7)    0.02679 (5)   0.0421 (4)           
  O1    0.84762 (17)   0.29479 (8)     0.21049 (6)   0.0336 (4)           
  O2    0.72134 (16)   0.23172 (8)     0.27348 (6)   0.0327 (4)           
  O3    0.89423 (17)   0.10570 (8)     0.23361 (6)   0.0326 (4)           
  O4    0.72044 (15)   0.01316 (8)     0.23007 (5)   0.0227 (4)           
  N2    0.75230 (19)   0.24606 (10)    0.22593 (7)   0.0206 (4)           
  N3    0.7648 (2)     0.07741 (10)    0.21850 (6)   0.0198 (4)           
  C1    0.5770 (2)     0.23578 (11)    0.14335 (7)   0.0154 (5)           
  C2    0.6654 (2)     0.20278 (11)    0.18389 (8)   0.0152 (5)           
  C3    0.6626 (2)     0.12295 (11)    0.18302 (7)   0.0151 (5)           
  C4    0.5731 (2)     0.09335 (10)    0.14100 (7)   0.0145 (5)           
  C11   0.5395 (2)     0.31580 (10)    0.13231 (8)   0.0153 (5)           
  C12   0.5170 (2)     0.36726 (11)    0.17431 (8)   0.0177 (5)           
  H12   0.5278         0.3514          0.2105        0.021\*              
  C13   0.4788 (2)     0.44149 (11)    0.16326 (8)   0.0182 (5)           
  H13   0.4654         0.4758          0.1918        0.022\*              
  C14   0.4601 (2)     0.46509 (11)    0.10993 (8)   0.0169 (5)           
  C15   0.4800 (2)     0.41410 (11)    0.06754 (8)   0.0213 (5)           
  H15   0.4659         0.4299          0.0315        0.026\*              
  C16   0.5204 (2)     0.34036 (11)    0.07853 (8)   0.0203 (5)           
  H16   0.5353         0.3064          0.0498        0.024\*              
  C17   0.4211 (2)     0.54560 (12)    0.09785 (9)   0.0225 (5)           
  C21   0.5441 (2)     0.01459 (11)    0.12329 (8)   0.0154 (5)           
  C22   0.5951 (2)     −0.00879 (11)   0.07186 (8)   0.0191 (5)           
  H22   0.6485         0.0252          0.0488        0.023\*              
  C23   0.5672 (2)     −0.08169 (11)   0.05477 (8)   0.0204 (5)           
  H23   0.6030         −0.0973         0.0204        0.024\*              
  C24   0.4859 (2)     −0.13201 (11)   0.08861 (7)   0.0167 (5)           
  C25   0.4314 (2)     −0.10885 (11)   0.13930 (8)   0.0182 (5)           
  H25   0.3749         −0.1424         0.1618        0.022\*              
  C26   0.4607 (2)     −0.03585 (11)   0.15652 (8)   0.0171 (5)           
  H26   0.4242         −0.0203         0.1908        0.021\*              
  C27   0.4586 (3)     −0.21090 (12)   0.06936 (9)   0.0249 (5)           
  ----- -------------- --------------- ------------- -------------------- --

Atomic displacement parameters (Å^2^) {#tablewrapadps}
=====================================

  ----- ------------- ------------- ------------- -------------- -------------- --------------
        *U*^11^       *U*^22^       *U*^33^       *U*^12^        *U*^13^        *U*^23^
  S     0.0205 (3)    0.0148 (3)    0.0238 (3)    −0.0007 (3)    −0.0048 (3)    0.0006 (2)
  F1    0.0375 (8)    0.0209 (7)    0.0339 (8)    0.0100 (6)     0.0032 (6)     −0.0016 (6)
  F2    0.0225 (7)    0.0184 (7)    0.0654 (9)    −0.0028 (6)    0.0090 (6)     0.0108 (6)
  F3    0.0315 (7)    0.0291 (8)    0.0345 (8)    0.0085 (6)     −0.0084 (6)    0.0057 (6)
  F4    0.0709 (10)   0.0208 (7)    0.0391 (8)    −0.0164 (7)    0.0180 (7)     −0.0038 (6)
  F5    0.0265 (8)    0.0240 (7)    0.0738 (10)   0.0025 (6)     0.0122 (7)     −0.0171 (7)
  F6    0.0447 (8)    0.0355 (8)    0.0462 (9)    −0.0044 (6)    −0.0134 (7)    −0.0163 (7)
  O1    0.0313 (9)    0.0344 (10)   0.0351 (9)    −0.0202 (8)    −0.0052 (8)    0.0047 (8)
  O2    0.0415 (10)   0.0389 (10)   0.0176 (9)    −0.0115 (8)    −0.0001 (8)    −0.0018 (8)
  O3    0.0219 (9)    0.0289 (9)    0.0469 (10)   −0.0039 (7)    −0.0169 (8)    −0.0003 (7)
  O4    0.0227 (9)    0.0182 (8)    0.0271 (9)    −0.0001 (7)    0.0004 (7)     0.0057 (7)
  N2    0.0183 (11)   0.0192 (11)   0.0244 (12)   0.0025 (9)     −0.0038 (9)    −0.0018 (9)
  N3    0.0189 (11)   0.0199 (11)   0.0206 (10)   0.0016 (9)     0.0001 (9)     −0.0022 (9)
  C1    0.0117 (11)   0.0178 (12)   0.0167 (11)   −0.0027 (9)    0.0006 (9)     −0.0006 (10)
  C2    0.0112 (11)   0.0169 (12)   0.0177 (12)   −0.0046 (10)   0.0003 (9)     −0.0032 (10)
  C3    0.0109 (12)   0.0179 (12)   0.0166 (12)   0.0014 (10)    0.0006 (10)    0.0029 (10)
  C4    0.0093 (11)   0.0180 (12)   0.0163 (11)   0.0018 (9)     0.0024 (9)     0.0021 (10)
  C11   0.0083 (11)   0.0163 (12)   0.0213 (12)   −0.0042 (9)    0.0005 (10)    0.0001 (10)
  C12   0.0155 (12)   0.0197 (12)   0.0179 (11)   −0.0020 (10)   −0.0018 (10)   0.0029 (10)
  C13   0.0146 (12)   0.0175 (12)   0.0226 (12)   −0.0021 (10)   0.0025 (10)    −0.0028 (10)
  C14   0.0101 (11)   0.0158 (12)   0.0248 (12)   −0.0031 (9)    −0.0007 (10)   0.0020 (10)
  C15   0.0216 (12)   0.0206 (13)   0.0217 (12)   −0.0025 (11)   −0.0021 (10)   0.0030 (10)
  C16   0.0214 (12)   0.0175 (12)   0.0220 (12)   −0.0015 (11)   0.0013 (10)    −0.0032 (10)
  C17   0.0189 (13)   0.0217 (13)   0.0268 (14)   0.0010 (11)    0.0009 (11)    −0.0012 (11)
  C21   0.0106 (12)   0.0166 (12)   0.0190 (12)   0.0024 (9)     −0.0041 (9)    0.0000 (9)
  C22   0.0172 (12)   0.0196 (13)   0.0205 (12)   −0.0027 (10)   0.0001 (10)    0.0036 (10)
  C23   0.0193 (12)   0.0240 (13)   0.0179 (12)   −0.0014 (10)   0.0025 (10)    −0.0039 (10)
  C24   0.0109 (11)   0.0160 (11)   0.0233 (12)   0.0002 (10)    −0.0014 (10)   −0.0021 (9)
  C25   0.0131 (12)   0.0182 (12)   0.0232 (12)   0.0006 (9)     0.0016 (10)    0.0045 (10)
  C26   0.0151 (12)   0.0181 (12)   0.0182 (11)   0.0039 (10)    0.0015 (10)    −0.0002 (9)
  C27   0.0233 (14)   0.0249 (13)   0.0266 (13)   −0.0003 (11)   0.0048 (12)    −0.0020 (11)
  ----- ------------- ------------- ------------- -------------- -------------- --------------

Geometric parameters (Å, °) {#tablewrapgeomlong}
===========================

  ----------------- ------------- ----------------- -------------
  S---C4            1.7119 (19)   C12---C13         1.373 (2)
  S---C1            1.7173 (19)   C12---H12         0.9300
  F1---C17          1.329 (2)     C13---C14         1.375 (2)
  F2---C17          1.344 (2)     C13---H13         0.9300
  F3---C17          1.346 (2)     C14---C15         1.381 (2)
  F4---C27          1.320 (2)     C14---C17         1.485 (3)
  F5---C27          1.330 (2)     C15---C16         1.368 (3)
  F6---C27          1.347 (2)     C15---H15         0.9300
  O1---N2           1.2187 (19)   C16---H16         0.9300
  O2---N2           1.2147 (18)   C21---C26         1.383 (2)
  O3---N3           1.2249 (18)   C21---C22         1.386 (2)
  O4---N3           1.2226 (18)   C22---C23         1.371 (3)
  N2---C2           1.462 (2)     C22---H22         0.9300
  N3---C3           1.446 (2)     C23---C24         1.382 (3)
  C1---C2           1.356 (2)     C23---H23         0.9300
  C1---C11          1.469 (2)     C24---C25         1.377 (2)
  C2---C3           1.408 (2)     C24---C27         1.485 (3)
  C3---C4           1.363 (2)     C25---C26         1.375 (2)
  C4---C21          1.474 (2)     C25---H25         0.9300
  C11---C12         1.382 (2)     C26---H26         0.9300
  C11---C16         1.391 (2)                       
                                                    
  C4---S---C1       94.24 (9)     C15---C16---C11   120.54 (18)
  O2---N2---O1      125.10 (17)   C15---C16---H16   119.7
  O2---N2---C2      117.48 (17)   C11---C16---H16   119.7
  O1---N2---C2      117.40 (17)   F1---C17---F2     106.49 (16)
  O4---N3---O3      124.26 (17)   F1---C17---F3     106.33 (16)
  O4---N3---C3      118.87 (17)   F2---C17---F3     105.24 (16)
  O3---N3---C3      116.82 (17)   F1---C17---C14    113.47 (17)
  C2---C1---C11     131.07 (18)   F2---C17---C14    112.20 (16)
  C2---C1---S       108.86 (14)   F3---C17---C14    112.51 (17)
  C11---C1---S      119.92 (14)   C26---C21---C22   119.21 (18)
  C1---C2---C3      114.15 (17)   C26---C21---C4    120.86 (17)
  C1---C2---N2      123.10 (18)   C22---C21---C4    119.88 (17)
  C3---C2---N2      122.72 (18)   C23---C22---C21   120.34 (19)
  C4---C3---C2      113.78 (17)   C23---C22---H22   119.8
  C4---C3---N3      123.16 (18)   C21---C22---H22   119.8
  C2---C3---N3      122.46 (18)   C22---C23---C24   120.00 (18)
  C3---C4---C21     131.90 (18)   C22---C23---H23   120.0
  C3---C4---S       108.95 (14)   C24---C23---H23   120.0
  C21---C4---S      119.11 (14)   C25---C24---C23   120.11 (18)
  C12---C11---C16   118.74 (18)   C25---C24---C27   120.92 (18)
  C12---C11---C1    121.51 (17)   C23---C24---C27   118.97 (18)
  C16---C11---C1    119.71 (17)   C26---C25---C24   119.76 (18)
  C13---C12---C11   120.72 (17)   C26---C25---H25   120.1
  C13---C12---H12   119.6         C24---C25---H25   120.1
  C11---C12---H12   119.6         C25---C26---C21   120.55 (18)
  C12---C13---C14   119.99 (18)   C25---C26---H26   119.7
  C12---C13---H13   120.0         C21---C26---H26   119.7
  C14---C13---H13   120.0         F4---C27---F5     107.18 (18)
  C13---C14---C15   119.97 (19)   F4---C27---F6     105.61 (16)
  C13---C14---C17   120.08 (18)   F5---C27---F6     105.08 (16)
  C15---C14---C17   119.94 (18)   F4---C27---C24    113.67 (17)
  C16---C15---C14   120.02 (18)   F5---C27---C24    112.76 (17)
  C16---C15---H15   120.0         F6---C27---C24    111.91 (18)
  C14---C15---H15   120.0                           
  ----------------- ------------- ----------------- -------------

Hydrogen-bond geometry (Å, °) {#tablewraphbondslong}
=============================

  ------------------- --------- --------- ----------- ---------------
  *D*---H···*A*       *D*---H   H···*A*   *D*···*A*   *D*---H···*A*
  C13---H13···O4^i^   0.93      2.52      3.320 (2)   144
  ------------------- --------- --------- ----------- ---------------

Symmetry codes: (i) −*x*+1, *y*+1/2, −*z*+1/2.

###### Hydrogen-bond geometry (Å, °)

  *D*---H⋯*A*       *D*---H   H⋯*A*   *D*⋯*A*     *D*---H⋯*A*
  ----------------- --------- ------- ----------- -------------
  C13---H13⋯O4^i^   0.93      2.52    3.320 (2)   144

Symmetry code: (i) .
