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

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ISSN: 2056-9890

2-(1,3-Di­thiol-2-yl­­idene)-1,3-di­thiole-4-carbaldehyde

aYoungstown State University, One University Plaza, Youngstown, OH 44555-3663, USA, and bDepartment of Chemistry, University of Bremen, Leobener Strasse, NW 2C, D-28359 Bremen, Germany
*Correspondence e-mail: vazov@uni-bremen.de

(Received 13 June 2013; accepted 20 June 2013; online 26 June 2013)

The structure of the title compound, C7H4OS4, at 100 K has ortho­rhom­bic symmetry. In the crystal, tetra­thia­fulvalene mol­ecules form π-stacks along the a axis, with a stacking distance of 3.4736 (6) Å. Along the b axis, parallel stacks are inter­connected with each other through a network of weak C—H⋯O hydrogen bonds and short S⋯S contacts [3.4813 (7) Å]. Additional short S⋯S contacts [3.4980 (9) Å] join parallel stacks along the c axis.

Related literature

For tetra­thia­fulvalene derivatives and their applications, see: Yamada & Sugimoto (2004[Yamada, J. & Sugimoto, T. (2004). In TTF Chemistry: Fundamentals and Applications of Tetrathiafulvalenes. Berlin, Heidelberg, New York: Springer-Verlag.]); Segura & Martín (2001[Segura, J. L. & Martín, N. (2001). Angew. Chem. Int. Ed. 40, 1372-1409.]). For a review on synthetic chemistry of tetra­thia­fulvalenes, see: Fabre (2004[Fabre, J. M. (2004). Chem. Rev. 104, 5133-5150.]). For a previous synthesis of the title compound, see: Garín et al. (1994[Garín, J., Orduna, J., Uriel, S., Moore, A. J., Bryce, M. R., Wegener, S., Yufit, D. S. & Howard, A. K. (1994). Synthesis, pp. 489-493.]). For reviews on `weak' non-classical hydrogen bonding, see: Steiner (2002[Steiner, T. (2002). Angew. Chem. Int. Ed. 41, 48-76.]); Desiraju (2005[Desiraju, G. R. (2005). Chem. Commun. pp. 2995-3001.]). For reviews on halogen–halogen contacts, see: Metrangolo et al. (2008[Metrangolo, P., Meyer, F., Pilati, T., Resnati, G. & Terraneo, G. (2008). Angew. Chem. Int. Ed. 47, 6114-6127.]).

[Scheme 1]

Experimental

Crystal data
  • C7H4OS4

  • Mr = 232.34

  • Orthorhombic, P 21 21 21

  • a = 3.8466 (3) Å

  • b = 7.4052 (7) Å

  • c = 30.577 (3) Å

  • V = 870.99 (13) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 1.03 mm−1

  • T = 100 K

  • 0.50 × 0.21 × 0.13 mm

Data collection
  • Bruker SMART APEX CCD diffractometer

  • Absorption correction: multi-scan (SADABS in APEX2; Bruker, 2012[Bruker (2012). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.675, Tmax = 0.746

  • 6998 measured reflections

  • 2734 independent reflections

  • 2663 reflections with I > 2σ(I)

  • Rint = 0.015

Refinement
  • R[F2 > 2σ(F2)] = 0.024

  • wR(F2) = 0.057

  • S = 1.13

  • 2734 reflections

  • 109 parameters

  • H-atom parameters constrained

  • Δρmax = 0.45 e Å−3

  • Δρmin = −0.25 e Å−3

  • Absolute structure: Flack x determined using 985 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons & Flack, 2004[Parsons, S. & Flack, H. (2004). Acta Cryst. A60, s61.]), 1024 Friedel pairs

  • Flack parameter: 0.01 (4)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C1—H1⋯O1i 0.95 2.38 3.228 (3) 149
C3—H3⋯O1i 0.95 2.69 3.445 (3) 137
Symmetry code: (i) [-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2012[Bruker (2012). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2012[Bruker (2012). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, 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: SHELXL2013 (Sheldrick, 2013[Sheldrick, G. M. (2013). SHELXL2013. University of Göttingen, Germany.]) and SHELXLE (Hübschle et al., 2011[Hübschle, C. B., Sheldrick, G. M. & Dittrich, B. (2011). J. Appl. Cryst. 44, 1281-1284.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) 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: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]) and enCIFer (Allen et al., 2004[Allen, F. H., Johnson, O., Shields, G. P., Smith, B. R. & Towler, M. (2004). J. Appl. Cryst. 37, 335-338.]).

Supporting information


Comment top

The title compound, commonly known as 4-formyltetrathiafulvalene, was prepared from tetrathiafulvalene (TTF) and can serve as an intermediate for the synthesis of 4-(hydroxymethyl)tetrathiafulvalene by reduction with NaBH4, of conjugated TTF derivatives by means of Wittig reaction (Garín et al., 1994), of TTF imines by reaction with amines, and of other functional tetrathiafulvalenes (Yamada & Sugimoto, 2004; Fabre, 2004).

The molecular structure of the title compound with atom numbering scheme is shown in Fig. 1. Bond lengths and angles may be considered normal. The molecular framework excluding the carbonyl group is essentially planar, with a maximum deviation of fitted atoms from the least-square plane, defined by the heavy atoms of the TTF backbone, of 0.042 (2) Å for C6. Atoms of the carbonyl group show more substantial out of plane deviation of 0.128 (2) Å for C1 and of 0.2393 (19) Å for O1, respectively.

Details of the packing interactions are given in the Tables. Molecules of the 4-formyltetrathiafulvalene form π-stacks along the a axis with a distance of 3.4736 (6) Å between the least-square planes defined by the S1, S2, S3, and S4 atoms (Figs. 1 &2). Parallel π-stacks are interconnected with each other along the b axis by C1—H1···O1i and C3—H3···O1i (symmetry code: (i) -x, y + 1/2, -z + 1/2) short contacts, which can be classified as non-classical hydrogen bonds. Additionally, two S···S short contacts, which may be similar in nature to halogen bonds (Metrangolo et al., 2008), are observed in the crystal structure. The shorter S2···S4iv (3.4813 (7) Å) contacts (symmetry code: (iv) x, 1 + y, z) are observed along the b axis. The longer (3.4980 (9) Å) S3···S3ii/iii contacts (symmetry codes: (ii) -1/2 + x, 1/2 - y, -z; (iii) 1/2 + x, 1/2 - y, -z) bind parallel π-stacks with each other along the c axis.

Related literature top

For tetrathiafulvalene derivatives and their applications, see: Yamada & Sugimoto (2004); Segura & Martín (2001). For a review on synthetic chemistry of tetrathiafulvalenes, see: Fabre (2004). For a previous synthesis of the title compound, see: Garín et al. (1994). For reviews on `weak' non-classical hydrogen bonding, see: Steiner (2002); Desiraju (2005). For reviews on halogen–halogen contacts, see: Metrangolo et al. (2008).

Experimental top

The title compound was prepared as described by Garín et al. (1994) by treatment of monolithio-TTF with N-methyl-N-phenylformamide in dry Et2O. The product was obtained as a deep red microcrystalline solid. Crystals suitable for X-ray diffraction were grown by slow evaporation of a solution in benzene/cyclohexane. Mp: 382–383 K; Lit: 382–383 K (Garín et al., 1994). 1H NMR (200 MHz, CDCl3): δ 6.33 (d, J = 6.5 Hz, 1 H), 6.36 (d, J = 6.2 Hz, 1 H), 7.42 (s, 1 H), 9.48 (s, 1 H).

Refinement top

Hydrogen atoms were included at calculated positions using a riding model with aromatic and formyl C—H = 0.95. The Uiso(H) values were fixed at 1.2 × Ueq(C) of the parent C atom.

Structure description top

The title compound, commonly known as 4-formyltetrathiafulvalene, was prepared from tetrathiafulvalene (TTF) and can serve as an intermediate for the synthesis of 4-(hydroxymethyl)tetrathiafulvalene by reduction with NaBH4, of conjugated TTF derivatives by means of Wittig reaction (Garín et al., 1994), of TTF imines by reaction with amines, and of other functional tetrathiafulvalenes (Yamada & Sugimoto, 2004; Fabre, 2004).

The molecular structure of the title compound with atom numbering scheme is shown in Fig. 1. Bond lengths and angles may be considered normal. The molecular framework excluding the carbonyl group is essentially planar, with a maximum deviation of fitted atoms from the least-square plane, defined by the heavy atoms of the TTF backbone, of 0.042 (2) Å for C6. Atoms of the carbonyl group show more substantial out of plane deviation of 0.128 (2) Å for C1 and of 0.2393 (19) Å for O1, respectively.

Details of the packing interactions are given in the Tables. Molecules of the 4-formyltetrathiafulvalene form π-stacks along the a axis with a distance of 3.4736 (6) Å between the least-square planes defined by the S1, S2, S3, and S4 atoms (Figs. 1 &2). Parallel π-stacks are interconnected with each other along the b axis by C1—H1···O1i and C3—H3···O1i (symmetry code: (i) -x, y + 1/2, -z + 1/2) short contacts, which can be classified as non-classical hydrogen bonds. Additionally, two S···S short contacts, which may be similar in nature to halogen bonds (Metrangolo et al., 2008), are observed in the crystal structure. The shorter S2···S4iv (3.4813 (7) Å) contacts (symmetry code: (iv) x, 1 + y, z) are observed along the b axis. The longer (3.4980 (9) Å) S3···S3ii/iii contacts (symmetry codes: (ii) -1/2 + x, 1/2 - y, -z; (iii) 1/2 + x, 1/2 - y, -z) bind parallel π-stacks with each other along the c axis.

For tetrathiafulvalene derivatives and their applications, see: Yamada & Sugimoto (2004); Segura & Martín (2001). For a review on synthetic chemistry of tetrathiafulvalenes, see: Fabre (2004). For a previous synthesis of the title compound, see: Garín et al. (1994). For reviews on `weak' non-classical hydrogen bonding, see: Steiner (2002); Desiraju (2005). For reviews on halogen–halogen contacts, see: Metrangolo et al. (2008).

Computing details top

Data collection: APEX2 (Bruker, 2012); cell refinement: APEX2 (Bruker, 2012); data reduction: APEX2 (Bruker, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2013) and SHELXLE (Hübschle et al., 2011); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2006); software used to prepare material for publication: publCIF (Westrip, 2010) and enCIFer (Allen et al., 2004).

Figures top
[Figure 1] Fig. 1. ORTEP–3 plot of the title molecule with the atom numbering scheme. Displacement ellipsoids are represented at 50% probability levels. H atoms are presented as a small spheres of arbitrary radius.
[Figure 2] Fig. 2. Crystal packing of the title compound viewed along the a axis. Hydrogen bonds are shown as solid black lines, short S3···S3 contacts are shown as solid blue lines, and short S2···S4 contacts are represented as dotted blue lines.
[Figure 3] Fig. 3. Crystal packing of the title compound viewed along the b axis. Hydrogen bonds are shown as solid black lines, short S3···S3 contacts are shown as solid blue lines.
2-(1,3-Dithiol-2-ylidene)-1,3-dithiole-4-carbaldehyde top
Crystal data top
C7H4OS4Dx = 1.772 Mg m3
Mr = 232.34Melting point: 383 K
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
a = 3.8466 (3) ÅCell parameters from 4789 reflections
b = 7.4052 (7) Åθ = 2.8–31.4°
c = 30.577 (3) ŵ = 1.03 mm1
V = 870.99 (13) Å3T = 100 K
Z = 4Plate, red
F(000) = 4720.50 × 0.21 × 0.13 mm
Data collection top
Bruker SMART APEX CCD
diffractometer
2663 reflections with I > 2σ(I)
Radiation source: fine focus sealed tubeRint = 0.015
ω and φ scansθmax = 31.9°, θmin = 1.3°
Absorption correction: multi-scan
(SADABS in APEX2; Bruker, 2012)
h = 55
Tmin = 0.675, Tmax = 0.746k = 1010
6998 measured reflectionsl = 4244
2734 independent 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)] = 0.024H-atom parameters constrained
wR(F2) = 0.057 w = 1/[σ2(Fo2) + (0.0237P)2 + 0.4121P]
where P = (Fo2 + 2Fc2)/3
S = 1.13(Δ/σ)max < 0.001
2734 reflectionsΔρmax = 0.45 e Å3
109 parametersΔρmin = 0.25 e Å3
0 restraintsAbsolute structure: Flack x determined using 985 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons & Flack, 2004), 1024 Friedel pairs.
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.01 (4)
Crystal data top
C7H4OS4V = 870.99 (13) Å3
Mr = 232.34Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 3.8466 (3) ŵ = 1.03 mm1
b = 7.4052 (7) ÅT = 100 K
c = 30.577 (3) Å0.50 × 0.21 × 0.13 mm
Data collection top
Bruker SMART APEX CCD
diffractometer
2734 independent reflections
Absorption correction: multi-scan
(SADABS in APEX2; Bruker, 2012)
2663 reflections with I > 2σ(I)
Tmin = 0.675, Tmax = 0.746Rint = 0.015
6998 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.024H-atom parameters constrained
wR(F2) = 0.057Δρmax = 0.45 e Å3
S = 1.13Δρmin = 0.25 e Å3
2734 reflectionsAbsolute structure: Flack x determined using 985 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons & Flack, 2004), 1024 Friedel pairs.
109 parametersAbsolute structure parameter: 0.01 (4)
0 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.1960 (6)0.3626 (3)0.24133 (7)0.0229 (4)
H10.09870.47450.25040.027*
C20.3148 (6)0.3446 (3)0.19636 (7)0.0178 (4)
C30.3234 (6)0.4823 (3)0.16743 (7)0.0188 (4)
H30.24170.59920.17510.023*
C40.5823 (5)0.2086 (3)0.12667 (7)0.0154 (4)
C50.7332 (5)0.1004 (3)0.09665 (7)0.0154 (4)
C60.9971 (6)0.1700 (3)0.05523 (7)0.0213 (4)
H61.07840.28660.04730.026*
C71.0078 (7)0.0331 (3)0.02682 (7)0.0213 (4)
H71.09590.04920.00190.026*
O10.2158 (5)0.2405 (2)0.26790 (5)0.0275 (4)
S10.47171 (14)0.13395 (6)0.17941 (2)0.01732 (10)
S20.48840 (15)0.43791 (6)0.11609 (2)0.01750 (10)
S30.85438 (14)0.17653 (7)0.04434 (2)0.01774 (11)
S40.82962 (14)0.12822 (7)0.10718 (2)0.01786 (11)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0258 (11)0.0227 (9)0.0202 (10)0.0009 (9)0.0027 (8)0.0048 (8)
C20.0168 (9)0.0174 (9)0.0190 (9)0.0009 (8)0.0026 (7)0.0033 (7)
C30.0204 (10)0.0154 (8)0.0206 (10)0.0022 (8)0.0014 (9)0.0033 (7)
C40.0151 (9)0.0134 (8)0.0177 (9)0.0006 (6)0.0023 (7)0.0024 (6)
C50.0150 (9)0.0132 (8)0.0180 (9)0.0011 (6)0.0020 (7)0.0027 (7)
C60.0193 (9)0.0186 (9)0.0260 (10)0.0023 (9)0.0008 (9)0.0069 (7)
C70.0201 (10)0.0217 (9)0.0221 (10)0.0006 (9)0.0005 (9)0.0056 (7)
O10.0359 (10)0.0274 (8)0.0192 (7)0.0016 (8)0.0012 (7)0.0002 (6)
S10.0208 (2)0.01368 (19)0.0175 (2)0.00034 (19)0.00125 (19)0.00193 (17)
S20.0205 (2)0.01230 (18)0.0197 (2)0.00120 (19)0.0006 (2)0.00242 (16)
S30.0183 (2)0.0181 (2)0.0169 (2)0.00035 (19)0.00033 (19)0.00149 (17)
S40.0192 (2)0.01267 (19)0.0217 (2)0.00182 (19)0.00120 (19)0.00094 (17)
Geometric parameters (Å, º) top
C1—O11.218 (3)C4—S21.7661 (19)
C1—C21.455 (3)C5—S31.759 (2)
C1—H10.9500C5—S41.763 (2)
C2—C31.350 (3)C6—C71.336 (3)
C2—S11.751 (2)C6—S41.742 (2)
C3—S21.725 (2)C6—H60.9500
C3—H30.9500C7—S31.745 (2)
C4—C51.349 (3)C7—H70.9500
C4—S11.757 (2)
O1—C1—C2122.9 (2)C4—C5—S4122.44 (15)
O1—C1—H1118.6S3—C5—S4114.71 (12)
C2—C1—H1118.6C7—C6—S4118.03 (16)
C3—C2—C1123.9 (2)C7—C6—H6121.0
C3—C2—S1118.05 (16)S4—C6—H6121.0
C1—C2—S1118.02 (16)C6—C7—S3117.70 (17)
C2—C3—S2117.48 (16)C6—C7—H7121.1
C2—C3—H3121.3S3—C7—H7121.1
S2—C3—H3121.3C2—S1—C494.30 (10)
C5—C4—S1122.80 (15)C3—S2—C495.26 (10)
C5—C4—S2122.29 (15)C7—S3—C594.82 (10)
S1—C4—S2114.90 (11)C6—S4—C594.69 (10)
C4—C5—S3122.85 (15)
O1—C1—C2—C3174.0 (2)C5—C4—S1—C2178.23 (18)
O1—C1—C2—S13.4 (3)S2—C4—S1—C20.66 (13)
C1—C2—C3—S2177.51 (17)C2—C3—S2—C40.5 (2)
S1—C2—C3—S20.1 (3)C5—C4—S2—C3178.19 (18)
S1—C4—C5—S3178.29 (12)S1—C4—S2—C30.71 (13)
S2—C4—C5—S30.5 (3)C6—C7—S3—C51.6 (2)
S1—C4—C5—S40.8 (3)C4—C5—S3—C7178.51 (18)
S2—C4—C5—S4179.63 (12)S4—C5—S3—C72.32 (14)
S4—C6—C7—S30.3 (3)C7—C6—S4—C51.2 (2)
C3—C2—S1—C40.3 (2)C4—C5—S4—C6178.61 (18)
C1—C2—S1—C4177.22 (18)S3—C5—S4—C62.21 (14)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···O1i0.952.383.228 (3)149
C3—H3···O1i0.952.693.445 (3)137
Symmetry code: (i) x, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC7H4OS4
Mr232.34
Crystal system, space groupOrthorhombic, P212121
Temperature (K)100
a, b, c (Å)3.8466 (3), 7.4052 (7), 30.577 (3)
V3)870.99 (13)
Z4
Radiation typeMo Kα
µ (mm1)1.03
Crystal size (mm)0.50 × 0.21 × 0.13
Data collection
DiffractometerBruker SMART APEX CCD
Absorption correctionMulti-scan
(SADABS in APEX2; Bruker, 2012)
Tmin, Tmax0.675, 0.746
No. of measured, independent and
observed [I > 2σ(I)] reflections
6998, 2734, 2663
Rint0.015
(sin θ/λ)max1)0.743
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.024, 0.057, 1.13
No. of reflections2734
No. of parameters109
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.45, 0.25
Absolute structureFlack x determined using 985 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons & Flack, 2004), 1024 Friedel pairs.
Absolute structure parameter0.01 (4)

Computer programs: APEX2 (Bruker, 2012), SHELXS97 (Sheldrick, 2008), SHELXL2013 (Sheldrick, 2013) and SHELXLE (Hübschle et al., 2011), ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2006), publCIF (Westrip, 2010) and enCIFer (Allen et al., 2004).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···O1i0.952.383.228 (3)148.7
C3—H3···O1i0.952.693.445 (3)136.9
Symmetry code: (i) x, y+1/2, z+1/2.
Sulfur-sulfur short contacts (Å) of the title compound top
System S···SS···SSymmetry code
S3···S3ii3.4980 (9)(ii) -1/2+x, 1/2-y, -z
S3···S3iii3.4980 (9)(iii) 1/2+x, 1/2-y, -z
S2···S4iv3.4813 (7)(iv) x, 1+y, z
 

Acknowledgements

The authors are grateful to Dr C. Vande Velde (Karel de Grote University College, Antwerp, Belgium) for helpful discussions. The X-ray diffractometer (MZ) was funded by NSF grant No. 0087210, Ohio Board of Regents grant CAP-491 and Youngstown State University.

References

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