supporting information


Acta Cryst. (2013). E69, o916    [ doi:10.1107/S1600536813013275 ]

Thio­phene-2-carbaldehyde azine

D. K. Geiger, H. C. Geiger and L. M. Szczesniak

Abstract top

The asymmetric unit of the title compound, C10H8N2S2, is composed of two independent half-mol­ecules, each residing on a center of symmetry. In the crystal, weak C-H...[pi] inter­actions join the two symmetry-independent molecules together into interlinked chains parallel to [011]. The crystal structure was refined as a two-component pseudo-merohedral twin using the twin law 001 0-10 100. The refined domain fractions are 0.516 (3) and 0.484 (3).

Comment top

The title compound was a side product in the attempted reduction of a nitro-substituted benzimidazole derivative but was subsequently rationally synthesized as outlined in the experimental section.

Thiophene-2-carbaldehyde azine crystallizes with two half-molecules in the asymmetric unit. Each sits on a crystallographically required center of symmetry. Figure 1 shows a perspective view of the two molecules with the atom-labeling scheme. The hydrazine substitutents adopt a (1E,2E) configuration, as required by the crystallographically imposed symmetry. The two molecules are essentially planar. The thiophene containing S1 is canted 1.63 (12)° from the molecular plane and the thiophene containing S2 is canted 1.63 (15)° from the molecular plane. The N1—C1—C2—S2 and N2—C6—C7—S2 torsional angles are 0.4 (6)° and 1.8 (7)°, respectively, and the N1'-N1—C1—C2 and N2'-N2—C6—C7 torsional angles are 178.3 (4)° and 178.9 (4)°, respectively. The orientation of the substituents is similar to that found for pyridine-4-carbaldehyde azine, 1.12 (9)°, (Shanmuga Sundara Raj et al., 2000) and the indole ring in (E)-1-diphenylmethylidene-2-[(1H-indol-3-yl)methylidene]hydrazine, 0.95 (10)°, (Archana et al., 2010).

A view of the unit cell is shown in Figure 2. Weak C—H···π interactions between the symmetry independent molecules result in chains parallel to [011]. The C1—H1···C8 and C1—H1···C9 intermolecular distances are 2.77 and 2.85 Å, respectively. There is a short intermolecular distance of C8—H8···C4 (2.77 Å).

Related literature top

For the structure of pyridine-4-carbaldehyde, see: Shanmuga Sundara Raj et al. (2000) and for the structure of (E)-1-diphenylmethylidene-2-[(1H-indol-3-yl)methylidene]hydrazine, see: Archana et al. (2010).

Experimental top

0.126 ml (4.05 mmol) of hydrazine hydrate in 1 ml of ethanol was slowly added to 0.82 ml (0.98 g, 8.8 mmol) of 2-thiophene carboxaldehyde in 35 ml of ethanol at room temperature with stirring. The reaction was refluxed for 4 h and monitored by TLC. The reaction mixture was cooled to 0°C and the product was obtained by vacuum filtration. 0.32 g obtained (33% yield). Rf = 0.88 (EtOAc/EtOH, 2:1 (v/v) on silica gel). mp = 147–149°C. 1H NMR (400 MHz, CDCl3): δ, 8.80 (s, 2H); 7.50 (d, 2H); 7.44 (d, 2H); 7.14 (dd, 2H). 13C NMR (CDCl3): δ, 155.80, 139.00, 132.50, 130.04, 127.84.

Single crystals suitable for X-ray diffraction were obtained by slow evaporation of an ethanol/ethylacetate solution.

Refinement top

The autosolve routine of the APEXII software (Bruker, 2010) chose an orthorhombic, C-centered cell, but no suitable space group could be found. Subsequently, the structure was solved in P21/n and refined to R1 = 0.17 and S = 3.27. Refinement as a pseudo-merohedral twin with the twin law 001 0–10 100 resulted in a dramatic improvement in the model. The domain fractions refined to 0.516 (3) and 0.484 (3).

The H atoms were refined using a riding model with a C—H distance of 0.95 Å and the thermal parameters were set using the approximation Uiso = 1.2Ueq(C).

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: PLATON (Spek, 2009) and Mercury (Macrae et al., 2008); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. Perspective view of the title compound showing the atom-labeling scheme used for the two half molecules in the asymmetric unit. Displacement ellipsoids of the nonhydrogen atoms are drawn at the 50% probability level.
[Figure 2] Fig. 2. The unit cell of the title compound showing the linked chains parallel to [011].
(1E,2E)-Bis[(thiophen-2-yl)methylidene]hydrazine top
Crystal data top
C10H8N2S2Dx = 1.393 Mg m3
Mr = 220.30Melting point: 420 K
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
a = 9.681 (2) ÅCell parameters from 1222 reflections
b = 11.399 (3) Åθ = 2.8–21.5°
c = 9.694 (2) ŵ = 0.47 mm1
β = 100.850 (9)°T = 200 K
V = 1050.6 (5) Å3Prism, yellow
Z = 40.50 × 0.20 × 0.20 mm
F(000) = 456
Data collection top
Bruker SMART X2S CCD
diffractometer
1890 independent reflections
Radiation source: XOS X-beam microfocus source1349 reflections with I > 2σ(I)
Doubly curved silicon crystal monochromatorRint = 0.073
Detector resolution: 8.3330 pixels mm-1θmax = 25.4°, θmin = 1.8°
ω scansh = 1111
Absorption correction: multi-scan
(SADABS; Bruker, 2010)
k = 1213
Tmin = 0.69, Tmax = 0.91l = 1111
7000 measured reflections
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) = 0.156H-atom parameters constrained
S = 0.99 w = 1/[σ2(Fo2) + (0.0825P)2]
where P = (Fo2 + 2Fc2)/3
1890 reflections(Δ/σ)max < 0.001
128 parametersΔρmax = 0.61 e Å3
0 restraintsΔρmin = 0.28 e Å3
Crystal data top
C10H8N2S2V = 1050.6 (5) Å3
Mr = 220.30Z = 4
Monoclinic, P21/nMo Kα radiation
a = 9.681 (2) ŵ = 0.47 mm1
b = 11.399 (3) ÅT = 200 K
c = 9.694 (2) Å0.50 × 0.20 × 0.20 mm
β = 100.850 (9)°
Data collection top
Bruker SMART X2S CCD
diffractometer
1890 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2010)
1349 reflections with I > 2σ(I)
Tmin = 0.69, Tmax = 0.91Rint = 0.073
7000 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0590 restraints
wR(F2) = 0.156H-atom parameters constrained
S = 0.99Δρmax = 0.61 e Å3
1890 reflectionsΔρmin = 0.28 e Å3
128 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
S10.15035 (15)0.24362 (18)0.24483 (16)0.0462 (4)
S20.25404 (15)0.26513 (11)0.35231 (15)0.0486 (5)
N10.0295 (4)0.0438 (3)0.0474 (4)0.0442 (12)
N20.0495 (4)0.4567 (3)0.4718 (4)0.0446 (13)
C10.0425 (5)0.1418 (4)0.0133 (5)0.0432 (14)
H10.01530.1470.11250.052*
C20.0969 (5)0.2439 (3)0.0643 (6)0.0361 (13)
C30.1093 (6)0.3536 (4)0.0119 (6)0.0484 (14)
H30.0840.37260.0850.058*
C40.1644 (5)0.4370 (4)0.1182 (6)0.0540 (15)
H40.18150.51710.10020.065*
C50.1889 (6)0.3885 (4)0.2458 (6)0.0519 (15)
H50.22440.43120.32910.062*
C60.0080 (5)0.3572 (4)0.4585 (5)0.0395 (13)
H60.10730.350.48430.047*
C70.0737 (5)0.2566 (4)0.4056 (5)0.0340 (13)
C80.0274 (6)0.1447 (4)0.3957 (6)0.0505 (15)
H80.06830.1220.42250.061*
C90.1364 (6)0.0664 (4)0.3416 (5)0.0572 (16)
H90.12250.01470.32650.069*
C100.2655 (6)0.1210 (4)0.3131 (6)0.0570 (16)
H100.35110.0820.27570.068*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0523 (12)0.0503 (7)0.0336 (10)0.0004 (5)0.0017 (7)0.0045 (5)
S20.0389 (11)0.0509 (7)0.0543 (13)0.0039 (6)0.0041 (7)0.0047 (6)
N10.048 (3)0.039 (2)0.043 (3)0.0068 (19)0.002 (2)0.0083 (19)
N20.040 (3)0.040 (2)0.053 (3)0.0068 (17)0.009 (2)0.0027 (19)
C10.055 (4)0.039 (2)0.037 (3)0.008 (2)0.015 (3)0.003 (2)
C20.028 (3)0.044 (2)0.037 (3)0.0046 (19)0.007 (2)0.004 (2)
C30.055 (4)0.045 (2)0.047 (3)0.000 (3)0.017 (3)0.001 (3)
C40.047 (4)0.041 (3)0.075 (4)0.001 (2)0.016 (3)0.002 (3)
C50.041 (3)0.053 (3)0.061 (4)0.004 (2)0.007 (3)0.015 (3)
C60.037 (3)0.042 (3)0.041 (3)0.001 (2)0.010 (2)0.001 (2)
C70.030 (3)0.041 (2)0.032 (3)0.0031 (19)0.010 (2)0.005 (2)
C80.045 (3)0.046 (3)0.065 (4)0.002 (2)0.022 (3)0.002 (3)
C90.083 (5)0.040 (3)0.054 (4)0.004 (3)0.026 (3)0.004 (2)
C100.071 (4)0.051 (3)0.048 (4)0.027 (3)0.007 (3)0.000 (3)
Geometric parameters (Å, º) top
S1—C51.693 (5)C3—H30.95
S1—C21.729 (6)C4—C51.335 (7)
S2—C101.685 (5)C4—H40.95
S2—C71.728 (5)C5—H50.95
N1—C11.280 (5)C6—C71.432 (6)
N1—N1i1.402 (7)C6—H60.95
N2—C61.281 (5)C7—C81.361 (6)
N2—N2ii1.412 (7)C8—C91.406 (7)
C1—C21.431 (6)C8—H80.95
C1—H10.95C9—C101.377 (7)
C2—C31.364 (6)C9—H90.95
C3—C41.429 (7)C10—H100.95
C5—S1—C291.6 (3)C4—C5—H5123.3
C10—S2—C791.9 (3)S1—C5—H5123.3
C1—N1—N1i112.6 (5)N2—C6—C7121.6 (5)
C6—N2—N2ii112.5 (5)N2—C6—H6119.2
N1—C1—C2121.8 (5)C7—C6—H6119.2
N1—C1—H1119.1C8—C7—C6127.5 (5)
C2—C1—H1119.1C8—C7—S2111.1 (4)
C3—C2—C1126.8 (5)C6—C7—S2121.4 (3)
C3—C2—S1110.4 (4)C7—C8—C9112.8 (5)
C1—C2—S1122.7 (3)C7—C8—H8123.6
C2—C3—C4112.9 (5)C9—C8—H8123.6
C2—C3—H3123.6C10—C9—C8112.2 (5)
C4—C3—H3123.6C10—C9—H9123.9
C5—C4—C3111.7 (5)C8—C9—H9123.9
C5—C4—H4124.1C9—C10—S2112.1 (4)
C3—C4—H4124.1C9—C10—H10124.0
C4—C5—S1113.5 (4)S2—C10—H10124.0
Symmetry codes: (i) x, y, z; (ii) x, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···C80.952.773.683 (7)161
C1—H1···C90.952.853.576 (7)134
C8—H8···C4iii0.952.773.663 (7)156
Symmetry code: (iii) x+1/2, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC10H8N2S2
Mr220.30
Crystal system, space groupMonoclinic, P21/n
Temperature (K)200
a, b, c (Å)9.681 (2), 11.399 (3), 9.694 (2)
β (°) 100.850 (9)
V3)1050.6 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.47
Crystal size (mm)0.50 × 0.20 × 0.20
Data collection
DiffractometerBruker SMART X2S CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2010)
Tmin, Tmax0.69, 0.91
No. of measured, independent and
observed [I > 2σ(I)] reflections
7000, 1890, 1349
Rint0.073
(sin θ/λ)max1)0.602
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.059, 0.156, 0.99
No. of reflections1890
No. of parameters128
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.61, 0.28

Computer programs: APEX2 (Bruker, 2010), SAINT (Bruker, 2010), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and Mercury (Macrae et al., 2008), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···C80.952.773.683 (7)161.4
C1—H1···C90.952.853.576 (7)133.8
C8—H8···C4i0.952.773.663 (7)156.3
Symmetry code: (i) x+1/2, y+1/2, z+1/2.
 
Acknowledgements top

This work was supported by a Congressionally directed grant from the US Department of Education (grant No. P116Z100020) for the X-ray diffractometer and a grant from the Geneseo Foundation.