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Acta Cryst. (2012). E68, o52    [ doi:10.1107/S1600536811051518 ]

2,5-Bis(1,3-dithiol-2-ylidene)-1,3-dithiolane-4-thione

K. Ueda, K. Suzuki, K. Kunimoto and K. Yoza

Abstract top

The asymmetric unit of the title compound, C9H4S7, contains two independent molecules, in one of which the central five-membered ring is disordered over two orientations in a 0.924 (3):0.076 (3) ratio. The molecular skeleton is almost planar: the average distance of the atoms from their mean plane is 0.128 (7) Å in the ordered molecule, and 0.088 (5) and 0.123 (2) Å in the major and minor disorder components, respectively. The ordered and disordered molecules form separate columns by stacking along the b axis. Adjacent columns interact via short S...S [3.33 (2), 3.434 (3), 3.444 (2), 3.503 (2), 3.519 (3) and 3.53 (4) Å] and S...H [2.814 (2), 2.87 (7), 2.92 (2), 2.9269 (18), 2.93 (2), 2.94 (2), 2.939 (2), 2.967 (2) and 2.974 (1) Å] contacts.

Comment top

Donor molecules featuring a skeleton of 2,5-di(1,3-dithiol-2-ylidene)-1,3-dithiolane-4-thione (I) and 2,5-di(1,3-dithiol-2-ylidene)-1,3-dithiolane-4-quinone (II) are used for the preparation of charge transfer (CT) complexes with magnetic metal anions (Wang et al., 2005, 2007; Hiraoka et al., 2005; Fujiwara et al., 2006, 2007). In CT salts these molecules can form unique crystal structures with channels in addition to the usual layer stacking structures as a result of intermolecular S···S contacts. Through an investigation of the unique molecular arrangements of the derivatives of (I) and (II) in their crystals, we found that the derivatives of (I) are stacked in the same orientation and the derivatives of (II) are alternately stacked in opposite directions (Ueda & Yoza, 2009a, 2009b, 2009c; Ueda et al., 2010). This result suggests that the stacking orientation of the derivatives is largely influenced by their molecular skeletons. To identify the stacking orientation of skeleton (I), we synthesized (I) and investigated its crystal structure.

The asymmetric unit contains two crystallographically independent molecules. One of the two independent molecules shows orientational disorder in the C=S containing five-membered ring with occupancies of 0.924 (3) (molecule A) and 0.076 (3) (molecule B). The other molecule of the asymmetric unit, molecule C, is ordered. The framework of (I) is almost planar: the mean deviation of the atoms from their mean plane is 0.088 (5) Å for A, 0.123 (2) Å for B and 0.128 (7) Å for C.

In the crystal structure, two different orientations of the molecules are present. Both orientations enclose a dihedral angle of about 27° with the ac plane, but the mean plane of the molecules is nearly parallel either with (011) or with (01–1) (Fig. 2). Molecules with the same orientation form stacks along the b axis. The stacked molecules are separated by interplanar distances greater than 3.54 Å and have a fairly poor overlap. However some effective side-by-side contacts are observed between molecules of adjacent columns (Fig. 3). The interaction between adjacent columns is accomplished through contacts between different sulfur atoms: S9···S3Bi = 3.33 (2) Å [(i): 1–x, 1/2+y, 1–z]; S8···S3Aii = 3.434 (3) Å [(ii): x, 1+y, 1+z]; S6···S6iii = 3.444 (2) Å [(iii):–x, 1/2+y, –z]; S3C···S10i = 3.503 (2) Å; S4···S9i = 3.519 (3) Å; S2B···S3Aiv = 3.53 (4) Å [(iv): x, 1+y, z]; and through contacts between sulfur and hydrogen atoms: S2C···H9Ai = 2.814 (2) Å, S1B···H15A = 2.87 (7); S3B···H11Aiv = 2.92 (2) Å; S5···H6Ai = 2.9269 (18) Å; S3B···H11Av = 2.93 (2) Å [(v): x, y, z–1]; S3B···H12Avi = 2.94 (2) Å [(vi): 1–x, –1/2+y, 1–z]; S2C···H9Avii = 2.939 (2)Å [(vii): –x, –1/2+y, 1–z]; S3A···H8Aiii = 2.967 (2) Å; S3C···H14Aviii = 2.974 (1) Å [(viii): –x, 1/2+y, 1–z]. These distances are shorter than the sum of corresponding van der Waals radii, i.e., 3.60 Å for S···S and 3.00 Å for S···H (Bondi, 1964).

Related literature top

For background to 2,5-di(1,3-dithiol-2-ylidene)-1,3-dithiolane-4-thione derivatives, see: Iwamatsu et al. (1999, 2000); Wang et al. (2005, 2007); Hiraoka et al. (2005); Fujiwara et al. (2006, 2007); Ueda & Yoza (2009a,b,c). For the synthesis, see: Ueda et al. (2010). For van der Waals radii, see: Bondi (1964).

Experimental top

Compound (I) was synthesized by a modification of the method used for the preparation of 2-[4,5-bis(ethylsulfanyl)-1,3-dithiol-2-ylidene]-5-(4,5-diiodo-1,3-dithiol-2-ylidene)-1,3-dithiolan-4-thione (Ueda et al., 2010). Bis(tetra-n-butylammonium)bis[2-(1,3-dithiol-2-ylidene)-1,3-dithiole-4,5-bis(thiolate)]zinc (194 mg, 0.170 mmol) reacted with 2-methylsulfanyl-1,3-dihiole-2-ylium tetrafluoroborate (89.3 mg, 0.378 mmol) in THF-DMF (4:1 = v/v) at room temperature under nitrogen, and stirring was carried out for 12 h. After separation of the reaction mixture by column chromatography on silica gel (eluent CS2) followed by recrystallization from 1:10 CS2/hexane, (I) was obtained as black needles in 79% yield.

Refinement top

The H atoms were geometrically positioned with C—H: 0.98 Å, and refined as riding, with Uiso = 1.5Ueq(C).

The following SHELX instructions were applied as restraints during refinement: SADI 0.01 S1C S2C S1A S2A S1B S2B / SADI 0.01 C6C S3C C6A S3A C6B S3B / SADI 0.01 C5C S1C C5A S1A C5B S1B / SADI 0.01 C6C C5C C6A C5A C6B C5B / SADI 0.01 S2C C6C S2A C6A S2B C6B / SADI 0.01 C4C S2C C4A S2A C4B S2B / SADI 0.01 S1C C4C S1A C4A S1B C4B / FLAT S1A S2A S3A C4A C5A C6A / FLAT S1B S2B S3B C4B C5B C6B / FLAT S1C S2C S3C C4C C5C C6C / SIMU 0.01 / ISOR 0.01.

Computing details top

Data collection: APEX2 (Bruker, 2010); cell refinement: SAINT (Bruker, 2010); data reduction: SAINT (Bruker, 2010); 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: XCIF (Bruker, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) showing atom labeling and 50% probability displacement ellipsoids for non-H-atoms.
[Figure 2] Fig. 2. Projection of the crystal packing of (I) down the bc plane.
[Figure 3] Fig. 3. (a) Projection of the crystal packing of molecules A and C in (I) down the ac plane. The S···S and S···H contacts are shown with blue solid lines. (b) Projection of the crystal packing of molecules B and C in (I) down the ac plane. The S···S and S···H contacts are shown with blue solid lines.
(I) top
Crystal data top
C9H4S7F(000) = 680
Mr = 336.54Dx = 1.852 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
a = 17.669 (5) ÅCell parameters from 794 reflections
b = 3.9110 (11) Åθ = 2.3–23.9°
c = 18.380 (5) ŵ = 1.27 mm1
β = 108.177 (4)°T = 93 K
V = 1206.8 (6) Å3Needle, black
Z = 40.09 × 0.02 × 0.02 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer
4975 independent reflections
Radiation source: Bruker TXS fine-focus rotating anode3396 reflections with I > 2σ(I)
Bruker Helios multilayer confocal mirrorRint = 0.054
Detector resolution: 8.333 pixels mm-1θmax = 27.5°, θmin = 1.9°
phi and ω scansh = 2215
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
k = 54
Tmin = 0.894, Tmax = 0.975l = 2223
6965 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.061H-atom parameters constrained
wR(F2) = 0.107 w = 1/[σ2(Fo2) + (0.0283P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.98(Δ/σ)max = 0.002
4975 reflectionsΔρmax = 0.63 e Å3
344 parametersΔρmin = 0.52 e Å3
421 restraintsAbsolute structure: Flack (1983), 1849 Friedel pairs
Primary atom site location: structure-invariant direct methodsFlack parameter: 0.18 (18)
Crystal data top
C9H4S7V = 1206.8 (6) Å3
Mr = 336.54Z = 4
Monoclinic, P21Mo Kα radiation
a = 17.669 (5) ŵ = 1.27 mm1
b = 3.9110 (11) ÅT = 93 K
c = 18.380 (5) Å0.09 × 0.02 × 0.02 mm
β = 108.177 (4)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer
4975 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
3396 reflections with I > 2σ(I)
Tmin = 0.894, Tmax = 0.975Rint = 0.054
6965 measured reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.061H-atom parameters constrained
wR(F2) = 0.107Δρmax = 0.63 e Å3
S = 0.98Δρmin = 0.52 e Å3
4975 reflectionsAbsolute structure: Flack (1983), 1849 Friedel pairs
344 parametersFlack parameter: 0.18 (18)
421 restraints
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*/UeqOcc. (<1)
C40.3976 (4)0.7807 (19)0.2942 (4)0.0247 (17)
C50.5339 (4)1.060 (2)0.3647 (4)0.035 (2)
H5A0.58701.14300.37720.042*
C60.4937 (4)1.091 (2)0.4121 (5)0.035 (2)
H6A0.51601.19900.46040.043*
C70.1148 (4)0.3154 (18)0.1591 (4)0.0190 (16)
C80.0317 (4)0.151 (2)0.1023 (4)0.0244 (17)
H8A0.08150.07670.06850.029*
C90.0268 (4)0.277 (2)0.1707 (4)0.0251 (18)
H9A0.07180.29150.18840.030*
C100.3122 (4)0.6221 (18)0.8314 (3)0.0139 (14)
C110.3743 (4)0.922 (2)0.9615 (4)0.0238 (17)
H11A0.38391.01341.01150.029*
C120.4298 (4)0.941 (2)0.9257 (4)0.0248 (17)
H12A0.47921.05260.94900.030*
C130.1820 (4)0.1225 (19)0.5609 (4)0.0154 (15)
C140.1298 (4)0.035 (2)0.4192 (4)0.0195 (16)
H14A0.09710.10980.37030.023*
C150.2009 (4)0.085 (2)0.4285 (3)0.0205 (17)
H15A0.22180.10030.38680.025*
C4A0.3347 (6)0.633 (2)0.2437 (4)0.0190 (17)0.924 (3)
C5A0.1947 (5)0.384 (2)0.1739 (4)0.0155 (15)0.924 (3)
C6A0.2391 (6)0.323 (3)0.1228 (5)0.021 (2)0.924 (3)
C4B0.191 (4)0.346 (17)0.181 (4)0.018 (4)0.076 (3)
C5B0.335 (6)0.59 (2)0.248 (3)0.023 (4)0.076 (3)
C6B0.331 (2)0.485 (10)0.173 (3)0.023 (3)0.076 (3)
C4C0.2640 (3)0.4578 (17)0.7717 (3)0.0170 (15)
C5C0.1960 (3)0.1937 (16)0.6374 (3)0.0151 (15)
C6C0.1387 (3)0.1573 (17)0.6762 (3)0.0158 (15)
S40.48789 (12)0.8603 (6)0.27620 (13)0.0385 (6)
S50.39615 (10)0.9263 (6)0.38449 (10)0.0270 (5)
S60.05349 (11)0.1230 (5)0.07570 (9)0.0211 (4)
S70.06754 (10)0.4126 (5)0.22574 (9)0.0201 (4)
S80.28575 (11)0.7290 (5)0.91400 (10)0.0219 (5)
S90.40896 (10)0.7580 (5)0.83649 (10)0.0225 (5)
S100.09618 (10)0.0554 (5)0.49847 (9)0.0189 (4)
S110.25580 (10)0.2146 (5)0.51919 (9)0.0204 (4)
S1A0.2450 (5)0.5721 (17)0.2628 (3)0.0191 (11)0.924 (3)
S2A0.33680 (13)0.4760 (6)0.15541 (12)0.0277 (6)0.924 (3)
S3A0.20601 (13)0.1459 (6)0.03754 (11)0.0275 (6)0.924 (3)
S1B0.246 (6)0.52 (2)0.268 (3)0.015 (6)0.076 (3)
S2B0.242 (2)0.312 (11)0.114 (2)0.021 (4)0.076 (3)
S3B0.4040 (14)0.512 (7)0.1345 (13)0.026 (6)0.076 (3)
S1C0.28927 (10)0.3657 (5)0.68923 (9)0.0193 (4)
S2C0.16991 (10)0.3150 (5)0.76938 (9)0.0193 (4)
S3C0.04904 (10)0.0125 (5)0.64141 (10)0.0211 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C40.025 (3)0.021 (4)0.032 (4)0.001 (3)0.014 (3)0.000 (3)
C50.021 (4)0.028 (5)0.055 (5)0.001 (3)0.012 (3)0.006 (4)
C60.024 (4)0.028 (5)0.048 (4)0.006 (3)0.002 (3)0.004 (4)
C70.026 (3)0.013 (4)0.017 (3)0.005 (3)0.004 (3)0.000 (3)
C80.027 (4)0.018 (4)0.022 (3)0.004 (3)0.001 (3)0.001 (3)
C90.026 (3)0.026 (4)0.025 (4)0.000 (3)0.011 (3)0.002 (3)
C100.016 (3)0.010 (3)0.014 (3)0.002 (3)0.003 (3)0.000 (3)
C110.028 (4)0.021 (4)0.017 (3)0.003 (3)0.001 (3)0.002 (3)
C120.022 (3)0.020 (4)0.022 (3)0.002 (3)0.009 (3)0.000 (3)
C130.017 (3)0.010 (3)0.020 (3)0.002 (3)0.006 (3)0.002 (3)
C140.020 (3)0.022 (4)0.013 (3)0.001 (3)0.000 (3)0.001 (3)
C150.026 (4)0.025 (4)0.012 (3)0.004 (3)0.008 (3)0.003 (3)
C4A0.020 (3)0.015 (4)0.024 (3)0.000 (3)0.009 (3)0.002 (3)
C5A0.022 (3)0.015 (3)0.011 (3)0.003 (3)0.008 (3)0.003 (3)
C6A0.033 (3)0.015 (4)0.014 (4)0.008 (3)0.007 (3)0.000 (3)
C4B0.025 (5)0.016 (6)0.015 (5)0.004 (5)0.006 (5)0.001 (5)
C5B0.024 (6)0.020 (6)0.026 (6)0.000 (5)0.010 (5)0.001 (5)
C6B0.027 (5)0.021 (5)0.024 (5)0.002 (5)0.010 (4)0.001 (5)
C4C0.012 (3)0.018 (4)0.018 (3)0.002 (3)0.001 (3)0.003 (3)
C5C0.012 (3)0.017 (4)0.012 (3)0.001 (3)0.002 (3)0.000 (3)
C6C0.019 (3)0.015 (4)0.012 (3)0.002 (3)0.004 (3)0.001 (3)
S40.0305 (11)0.0339 (16)0.0588 (14)0.0056 (11)0.0250 (11)0.0026 (12)
S50.0204 (10)0.0262 (12)0.0319 (11)0.0003 (9)0.0046 (9)0.0031 (10)
S60.0292 (11)0.0190 (11)0.0142 (9)0.0007 (9)0.0053 (8)0.0010 (9)
S70.0263 (10)0.0191 (11)0.0157 (9)0.0017 (9)0.0075 (8)0.0033 (9)
S80.0256 (10)0.0229 (12)0.0175 (9)0.0008 (9)0.0073 (8)0.0053 (9)
S90.0188 (10)0.0243 (12)0.0231 (10)0.0012 (9)0.0047 (8)0.0029 (9)
S100.0190 (9)0.0192 (11)0.0162 (9)0.0016 (9)0.0023 (8)0.0002 (9)
S110.0201 (10)0.0231 (12)0.0176 (9)0.0038 (9)0.0052 (8)0.0013 (8)
S1A0.0212 (12)0.020 (3)0.0185 (13)0.0022 (18)0.0095 (12)0.0003 (15)
S2A0.0320 (12)0.0275 (14)0.0304 (12)0.0002 (11)0.0197 (10)0.0006 (11)
S3A0.0421 (14)0.0252 (14)0.0197 (11)0.0054 (11)0.0162 (10)0.0023 (10)
S1B0.015 (7)0.016 (8)0.017 (8)0.000 (7)0.007 (6)0.002 (7)
S2B0.030 (6)0.018 (6)0.016 (6)0.007 (5)0.008 (5)0.004 (5)
S3B0.027 (8)0.029 (9)0.025 (8)0.009 (7)0.010 (6)0.002 (7)
S1C0.0158 (9)0.0238 (12)0.0174 (9)0.0032 (8)0.0040 (7)0.0057 (8)
S2C0.0171 (9)0.0224 (12)0.0178 (9)0.0004 (8)0.0047 (8)0.0012 (8)
S3C0.0156 (9)0.0243 (12)0.0218 (9)0.0010 (8)0.0035 (8)0.0004 (9)
Geometric parameters (Å, °) top
C4—C4A1.336 (11)C13—C5C1.378 (8)
C4—C5B1.38 (9)C13—S101.736 (7)
C4—S41.756 (7)C13—S111.744 (6)
C4—S51.763 (7)C14—C151.302 (8)
C5—C61.292 (9)C14—S101.739 (6)
C5—S41.758 (8)C14—H14A0.9500
C5—H5A0.9500C15—S111.723 (7)
C6—S51.759 (7)C15—H15A0.9500
C6—H6A0.9500C4A—S1A1.743 (6)
C7—C4B1.28 (6)C4A—S2A1.746 (7)
C7—C5A1.377 (9)C5A—C6A1.418 (9)
C7—S71.727 (6)C5A—S1A1.761 (6)
C7—S61.748 (7)C6A—S3A1.646 (9)
C8—C91.327 (9)C6A—S2A1.747 (10)
C8—S61.726 (7)C4B—S2B1.743 (10)
C8—H8A0.9500C4B—S1B1.745 (10)
C9—S71.742 (7)C5B—C6B1.417 (11)
C9—H9A0.9500C5B—S1B1.761 (10)
C10—C4C1.326 (8)C6B—S3B1.649 (11)
C10—S91.765 (6)C6B—S2B1.744 (11)
C10—S81.772 (6)C4C—S2C1.741 (6)
C11—C121.343 (8)C4C—S1C1.747 (6)
C11—S81.712 (7)C5C—C6C1.415 (7)
C11—H11A0.9500C5C—S1C1.760 (6)
C12—S91.721 (7)C6C—S3C1.652 (6)
C12—H12A0.9500C6C—S2C1.740 (6)
C4A—C4—S4123.6 (5)C4—C4A—S2A122.9 (7)
C5B—C4—S4125 (3)S1A—C4A—S2A115.1 (5)
C4A—C4—S5122.7 (5)C7—C5A—C6A125.6 (7)
C5B—C4—S5121 (3)C7—C5A—S1A117.0 (6)
S4—C4—S5113.6 (4)C6A—C5A—S1A117.4 (5)
C6—C5—S4118.2 (6)C5A—C6A—S3A126.5 (8)
C6—C5—H5A120.9C5A—C6A—S2A114.1 (6)
S4—C5—H5A120.9S3A—C6A—S2A119.4 (6)
C5—C6—S5117.8 (7)C7—C4B—S2B120 (5)
C5—C6—H6A121.1C7—C4B—S1B123 (5)
S5—C6—H6A121.1S2B—C4B—S1B114.8 (9)
C4B—C7—S7117 (3)C4—C5B—C6B123 (7)
C5A—C7—S7120.7 (5)C4—C5B—S1B123 (4)
C4B—C7—S6128 (3)C6B—C5B—S1B113 (5)
C5A—C7—S6125.0 (5)C5B—C6B—S3B126 (5)
S7—C7—S6114.3 (4)C5B—C6B—S2B118 (5)
C9—C8—S6119.1 (6)S3B—C6B—S2B116 (3)
C9—C8—H8A120.4C10—C4C—S2C122.5 (4)
S6—C8—H8A120.4C10—C4C—S1C123.1 (4)
C8—C9—S7115.5 (5)S2C—C4C—S1C114.4 (3)
C8—C9—H9A122.2C13—C5C—C6C124.4 (5)
S7—C9—H9A122.2C13—C5C—S1C118.0 (4)
C4C—C10—S9123.5 (4)C6C—C5C—S1C117.5 (4)
C4C—C10—S8123.4 (5)C5C—C6C—S3C126.5 (5)
S9—C10—S8113.2 (4)C5C—C6C—S2C113.8 (4)
C12—C11—S8117.7 (5)S3C—C6C—S2C119.6 (3)
C12—C11—H11A121.2C4—S4—C595.2 (4)
S8—C11—H11A121.2C6—S5—C495.2 (4)
C11—C12—S9118.2 (6)C8—S6—C794.7 (3)
C11—C12—H12A120.9C7—S7—C996.2 (3)
S9—C12—H12A120.9C11—S8—C1095.6 (3)
C5C—C13—S10126.7 (5)C12—S9—C1095.3 (3)
C5C—C13—S11119.1 (5)C13—S10—C1494.6 (3)
S10—C13—S11114.3 (4)C15—S11—C1395.3 (3)
C15—C14—S10118.4 (5)C4A—S1A—C5A95.6 (3)
C15—C14—H14A120.8C6A—S2A—C4A97.7 (5)
S10—C14—H14A120.8C4B—S1B—C5B98 (2)
C14—C15—S11117.5 (5)C6B—S2B—C4B96 (3)
C14—C15—H15A121.3C4C—S1C—C5C95.7 (3)
S11—C15—H15A121.3C6C—S2C—C4C98.3 (3)
C4—C4A—S1A122.0 (5)
references
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