5,6-Di-2-thienyl-2,3-dihydro­pyrazine

Hemamalini, M.; Fun, H.-K.

doi:10.1107/S1600536810012705

organic compounds

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ISSN: 2056-9890

Volume 66| Part 5| May 2010| Page o1062

https://doi.org/10.1107/S1600536810012705

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5,6-Di-2-thienyl-2,3-dihydropyrazine

Madhukar Hemamalini ^a ‡ and Hoong-Kun Fun ^a ^*§

^aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
^*Correspondence e-mail: hkfun@usm.my

(Received 5 April 2010; accepted 6 April 2010; online 14 April 2010)

In the title compound, C₁₂H₁₀N₂S₂, which was synthesized by the reaction of 2,2′-thenil and ethylenediamine, the dihedral angle between the two thiophene rings is 66.33 (9)°. In the crystal structure, intermolecular C—H⋯N hydrogen bonds link the molecules into infinite chains along the b axis and weak C—H⋯π interactions may further stabilize the structure.

Related literature

For backgroud to thenils, see: Shimon et al. (1993 ). For related structures, see: Crundwell et al. (2002a ,b , 2003 ); Linehan et al. (2003 ); Stacy et al. (2003 ). For bond-length data, see: Allen et al. (1987 ). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 ).

Experimental

Crystal data

C₁₂H₁₀N₂S₂
M_r = 246.34
Monoclinic, P 2₁
a = 5.5006 (9) Å
b = 7.5246 (12) Å
c = 14.116 (2) Å
β = 97.902 (5)°
V = 578.73 (16) Å³
Z = 2
Mo Kα radiation
μ = 0.43 mm⁻¹
T = 100 K
0.32 × 0.26 × 0.08 mm

Data collection

Bruker APEX DUO CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.875, T_max = 0.965
9583 measured reflections
4603 independent reflections
4295 reflections with I > 2σ(I)
R_int = 0.022

Refinement

R[F² > 2σ(F²)] = 0.032
wR(F²) = 0.115
S = 1.20
4603 reflections
145 parameters
1 restraint
All H-atom parameters refined
Δρ_max = 0.62 e Å⁻³
Δρ_min = −0.47 e Å⁻³
Absolute structure: Flack (1983 ), with 1899 Friedel pairs
Flack parameter: 0.07 (6)

Table 1
Hydrogen-bond geometry (Å, °)

Cg2 is the centroid of the S2/C9–C12 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1A⋯N1ⁱ	0.93	2.33	3.235 (3)	163
C2—H2A⋯Cg2ⁱⁱ	0.93	2.85	3.7737 (18)	171
Symmetry codes: (i) x+1, y+1, z; (ii) x, y+1, z.

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536810012705/hb5396sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810012705/hb5396Isup2.hkl

checkCIF report

Comment top

Thienyl-based guests have shown preferential inclusion into the host by keeping thienyl ring S atoms pointed away from the face of growing crystals, possibly to avoid unfavorable electrostatic interactions between sulfur lone pairs coplanar with the thiophene ring and molecules already incorporated into the growing crystal face (Shimon et al., 1993). The structural studies on thenoins (Crundwell et al., 2002a,b) and thenils (Crundwell et al., 2003), and other thiophene-containing molecules such as 2,5-diphenyl-3,4-dithien-3-ylcyclopentadien-1-one (Linehan et al., 2003) and 4-bromo-2-thiophenecarboxaldehyde (Stacy et al., 2003) have been reported in the literature. In continuation of this area of study, the crystal structure of the title compound, (I), is reported here.

In the molecule of the title compound (Fig. 1), the bond lengths (Allen et al., 1987) and angles are within normal ranges. The dihedral angle between the two thiophene rings S1/C1–C4 and S2/C9–C12 is 66.33 (9)°. In the crystal structure, intermolecular C—H···N hydrogen bonds (Table 1) link the molecules (Fig. 2) into infinite chains along the b axis, in which they may be effective in the stabilization of the structure. The crystal structure is further stabilized by C—H···π interactions (Table 1), involving the S2/C9–C12 (centroid Cg2) ring.

Related literature top

For backgroud to thenils, see: Shimon et al. (1993). For related structures, see: Crundwell et al. (2002a,b, 2003); Linehan et al. (2003); Stacy et al. (2003). For bond-length data, see: Allen et al. (1987). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

Experimental top

2,2'-thenil (55 mg) and ethylenediamine (15 mg) in ethanol/water (40 ml) were heated under reflux for 2 h with stirring. The resulting solution was then cooled to room temperature. After a few days of slow evaporation of the solvent, brown plates of (I) were obtained.

Structure description top

For backgroud to thenils, see: Shimon et al. (1993). For related structures, see: Crundwell et al. (2002a,b, 2003); Linehan et al. (2003); Stacy et al. (2003). For bond-length data, see: Allen et al. (1987). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The asymmetric unit of (I) with displacement ellipsoids drawn at the 50% probability level.
	Fig. 2. The crystal packing of (I), showing hydrogen-bonded (dashed lines) networks. H atoms are not involving the hydrogen bond interactions are omitted for clarity.

5,6-Di-2-thienyl-2,3-dihydropyrazine top

Crystal data top

C₁₂H₁₀N₂S₂	F(000) = 256
M_r = 246.34	D_x = 1.414 Mg m⁻³
Monoclinic, P2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 5014 reflections
a = 5.5006 (9) Å	θ = 2.9–34.8°
b = 7.5246 (12) Å	µ = 0.43 mm⁻¹
c = 14.116 (2) Å	T = 100 K
β = 97.902 (5)°	Plate, brown
V = 578.73 (16) Å³	0.32 × 0.26 × 0.08 mm
Z = 2

Data collection top

Bruker APEX DUO CCD area-detector diffractometer	4603 independent reflections
Radiation source: fine-focus sealed tube	4295 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.022
φ and ω scans	θ_max = 35.1°, θ_min = 1.5°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −8→8
T_min = 0.875, T_max = 0.965	k = −12→12
9583 measured reflections	l = −22→22

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.032	All H-atom parameters refined
wR(F²) = 0.115	w = 1/[σ²(F_o²) + (0.0632P)² + 0.0559P] where P = (F_o² + 2F_c²)/3
S = 1.20	(Δ/σ)_max < 0.001
4603 reflections	Δρ_max = 0.62 e Å⁻³
145 parameters	Δρ_min = −0.47 e Å⁻³
1 restraint	Absolute structure: Flack (1983), with 1899 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.07 (6)

Crystal data top

C₁₂H₁₀N₂S₂	V = 578.73 (16) Å³
M_r = 246.34	Z = 2
Monoclinic, P2₁	Mo Kα radiation
a = 5.5006 (9) Å	µ = 0.43 mm⁻¹
b = 7.5246 (12) Å	T = 100 K
c = 14.116 (2) Å	0.32 × 0.26 × 0.08 mm
β = 97.902 (5)°

Data collection top

Bruker APEX DUO CCD area-detector diffractometer	4603 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	4295 reflections with I > 2σ(I)
T_min = 0.875, T_max = 0.965	R_int = 0.022
9583 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.032	All H-atom parameters refined
wR(F²) = 0.115	Δρ_max = 0.62 e Å⁻³
S = 1.20	Δρ_min = −0.47 e Å⁻³
4603 reflections	Absolute structure: Flack (1983), with 1899 Friedel pairs
145 parameters	Absolute structure parameter: 0.07 (6)
1 restraint

Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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

	x	y	z	U_iso*/U_eq
S1	0.53730 (6)	0.88379 (6)	0.15567 (3)	0.02249 (9)
S2	−0.08370 (7)	0.37500 (7)	0.39261 (3)	0.02435 (10)
N1	−0.1511 (2)	0.42753 (19)	0.18646 (9)	0.0176 (2)
N2	0.2016 (2)	0.58341 (19)	0.08083 (8)	0.0167 (2)
C1	0.5372 (3)	1.0745 (3)	0.22117 (12)	0.0256 (3)
H1A	0.6518	1.1651	0.2206	0.031*
C2	0.3468 (3)	1.0777 (2)	0.27490 (12)	0.0225 (3)
H2A	0.3166	1.1719	0.3143	0.027*
C3	0.2025 (3)	0.9222 (2)	0.26367 (10)	0.0176 (2)
H3A	0.0665	0.9026	0.2948	0.021*
C4	0.2854 (2)	0.8021 (2)	0.20133 (9)	0.0141 (2)
C5	0.1765 (2)	0.6334 (2)	0.16622 (10)	0.0141 (2)
C6	0.0602 (3)	0.4259 (2)	0.04601 (10)	0.0199 (3)
H6A	0.1494	0.3194	0.0686	0.024*
H6B	0.0373	0.4245	−0.0234	0.024*
C7	−0.1875 (3)	0.4280 (2)	0.08163 (10)	0.0192 (3)
H7A	−0.2783	0.5333	0.0582	0.023*
H7B	−0.2817	0.3244	0.0579	0.023*
C8	0.0286 (2)	0.5231 (2)	0.22635 (9)	0.0136 (2)
C9	0.0980 (3)	0.5061 (2)	0.32993 (9)	0.0148 (2)
C10	0.3080 (3)	0.5582 (2)	0.38767 (10)	0.0199 (3)
H10A	0.4286	0.6292	0.3670	0.024*
C11	0.3203 (4)	0.4914 (3)	0.48252 (11)	0.0272 (3)
H11A	0.4496	0.5144	0.5307	0.033*
C12	0.1220 (4)	0.3904 (3)	0.49497 (11)	0.0296 (4)
H12A	0.1007	0.3360	0.5524	0.036*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.02124 (15)	0.02353 (19)	0.02375 (16)	−0.01080 (15)	0.00690 (12)	−0.00227 (15)
S2	0.02570 (17)	0.0293 (2)	0.01976 (15)	−0.00416 (17)	0.00917 (12)	0.00490 (16)
N1	0.0195 (5)	0.0164 (5)	0.0168 (4)	−0.0061 (4)	0.0022 (4)	−0.0014 (4)
N2	0.0188 (5)	0.0166 (5)	0.0151 (5)	−0.0038 (4)	0.0037 (4)	−0.0023 (4)
C1	0.0311 (8)	0.0176 (7)	0.0264 (7)	−0.0130 (6)	−0.0022 (6)	0.0022 (6)
C2	0.0283 (7)	0.0127 (6)	0.0246 (6)	−0.0012 (6)	−0.0030 (5)	−0.0006 (5)
C3	0.0178 (5)	0.0161 (6)	0.0186 (5)	−0.0030 (5)	0.0010 (4)	−0.0018 (5)
C4	0.0142 (5)	0.0126 (6)	0.0151 (5)	−0.0027 (4)	0.0007 (4)	0.0008 (4)
C5	0.0138 (5)	0.0131 (6)	0.0154 (5)	−0.0023 (4)	0.0019 (4)	0.0006 (4)
C6	0.0256 (6)	0.0162 (6)	0.0181 (5)	−0.0039 (5)	0.0042 (5)	−0.0054 (5)
C7	0.0203 (6)	0.0200 (7)	0.0164 (5)	−0.0066 (5)	0.0001 (4)	−0.0024 (5)
C8	0.0154 (5)	0.0113 (5)	0.0141 (5)	−0.0022 (4)	0.0027 (4)	0.0000 (4)
C9	0.0180 (5)	0.0129 (6)	0.0140 (5)	−0.0001 (5)	0.0036 (4)	0.0004 (4)
C10	0.0205 (6)	0.0206 (7)	0.0173 (5)	−0.0006 (5)	−0.0017 (5)	0.0012 (5)
C11	0.0331 (8)	0.0304 (9)	0.0163 (6)	0.0034 (7)	−0.0030 (5)	0.0006 (6)
C12	0.0399 (8)	0.0353 (10)	0.0151 (5)	0.0070 (9)	0.0087 (5)	0.0054 (7)

Geometric parameters (Å, º) top

S1—C1	1.707 (2)	C4—C5	1.461 (2)
S1—C4	1.7201 (14)	C5—C8	1.5040 (19)
S2—C12	1.7124 (19)	C6—C7	1.516 (2)
S2—C9	1.7317 (14)	C6—H6A	0.9700
N1—C8	1.2874 (18)	C6—H6B	0.9700
N1—C7	1.4658 (19)	C7—H7A	0.9700
N2—C5	1.2880 (18)	C7—H7B	0.9700
N2—C6	1.465 (2)	C8—C9	1.4652 (19)
C1—C2	1.375 (3)	C9—C10	1.376 (2)
C1—H1A	0.9300	C10—C11	1.423 (2)
C2—C3	1.411 (2)	C10—H10A	0.9300
C2—H2A	0.9300	C11—C12	1.361 (3)
C3—C4	1.382 (2)	C11—H11A	0.9300
C3—H3A	0.9300	C12—H12A	0.9300

C1—S1—C4	92.13 (8)	C7—C6—H6B	109.7
C12—S2—C9	91.82 (8)	H6A—C6—H6B	108.2
C8—N1—C7	115.50 (12)	N1—C7—C6	109.29 (12)
C5—N2—C6	115.48 (12)	N1—C7—H7A	109.8
C2—C1—S1	111.76 (12)	C6—C7—H7A	109.8
C2—C1—H1A	124.1	N1—C7—H7B	109.8
S1—C1—H1A	124.1	C6—C7—H7B	109.8
C1—C2—C3	112.51 (15)	H7A—C7—H7B	108.3
C1—C2—H2A	123.7	N1—C8—C9	117.84 (12)
C3—C2—H2A	123.7	N1—C8—C5	120.25 (12)
C4—C3—C2	112.59 (13)	C9—C8—C5	121.61 (12)
C4—C3—H3A	123.7	C10—C9—C8	130.47 (13)
C2—C3—H3A	123.7	C10—C9—S2	110.85 (10)
C3—C4—C5	128.94 (12)	C8—C9—S2	118.02 (10)
C3—C4—S1	110.99 (11)	C9—C10—C11	112.61 (15)
C5—C4—S1	119.83 (10)	C9—C10—H10A	123.7
N2—C5—C4	118.67 (13)	C11—C10—H10A	123.7
N2—C5—C8	120.18 (13)	C12—C11—C10	112.55 (15)
C4—C5—C8	121.10 (11)	C12—C11—H11A	123.7
N2—C6—C7	109.89 (12)	C10—C11—H11A	123.7
N2—C6—H6A	109.7	C11—C12—S2	112.16 (12)
C7—C6—H6A	109.7	C11—C12—H12A	123.9
N2—C6—H6B	109.7	S2—C12—H12A	123.9

C4—S1—C1—C2	−1.31 (14)	C7—N1—C8—C5	3.3 (2)
S1—C1—C2—C3	0.95 (19)	N2—C5—C8—N1	−29.3 (2)
C1—C2—C3—C4	0.1 (2)	C4—C5—C8—N1	148.07 (15)
C2—C3—C4—C5	−175.19 (14)	N2—C5—C8—C9	144.36 (15)
C2—C3—C4—S1	−1.03 (16)	C4—C5—C8—C9	−38.3 (2)
C1—S1—C4—C3	1.33 (12)	N1—C8—C9—C10	163.90 (16)
C1—S1—C4—C5	176.10 (12)	C5—C8—C9—C10	−9.9 (2)
C6—N2—C5—C4	−172.06 (13)	N1—C8—C9—S2	−5.87 (19)
C6—N2—C5—C8	5.4 (2)	C5—C8—C9—S2	−179.66 (11)
C3—C4—C5—N2	147.03 (16)	C12—S2—C9—C10	−0.12 (14)
S1—C4—C5—N2	−26.69 (19)	C12—S2—C9—C8	171.56 (13)
C3—C4—C5—C8	−30.4 (2)	C8—C9—C10—C11	−170.37 (16)
S1—C4—C5—C8	155.92 (11)	S2—C9—C10—C11	−0.03 (18)
C5—N2—C6—C7	37.17 (19)	C9—C10—C11—C12	0.2 (2)
C8—N1—C7—C6	38.97 (19)	C10—C11—C12—S2	−0.3 (2)
N2—C6—C7—N1	−60.13 (17)	C9—S2—C12—C11	0.26 (17)
C7—N1—C8—C9	−170.61 (13)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1A···N1ⁱ	0.93	2.33	3.235 (3)	163
C2—H2A···Cg2ⁱⁱ	0.93	2.85	3.7737 (18)	171

Symmetry codes: (i) x+1, y+1, z; (ii) x, y+1, z.

Experimental details

Crystal data
Chemical formula	C₁₂H₁₀N₂S₂
M_r	246.34
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	100
a, b, c (Å)	5.5006 (9), 7.5246 (12), 14.116 (2)
β (°)	97.902 (5)
V (Å³)	578.73 (16)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.43
Crystal size (mm)	0.32 × 0.26 × 0.08

Data collection
Diffractometer	Bruker APEX DUO CCD area-detector
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.875, 0.965
No. of measured, independent and observed [I > 2σ(I)] reflections	9583, 4603, 4295
R_int	0.022
(sin θ/λ)_max (Å⁻¹)	0.810

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.032, 0.115, 1.20
No. of reflections	4603
No. of parameters	145
No. of restraints	1
H-atom treatment	All H-atom parameters refined
Δρ_max, Δρ_min (e Å⁻³)	0.62, −0.47
Absolute structure	Flack (1983), with 1899 Friedel pairs
Absolute structure parameter	0.07 (6)

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1A···N1ⁱ	0.93	2.33	3.235 (3)	163
C2—H2A···Cg2ⁱⁱ	0.93	2.85	3.7737 (18)	171

Symmetry codes: (i) x+1, y+1, z; (ii) x, y+1, z.

Footnotes

‡Additional correspondence author, e-mail: mhemamalini2k3@yahoo.co.in.

§Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

The authors thank the Malaysian Government and Universiti Sains Malaysia for Research University Golden Goose grant No. 1001/PFIZIK/811012. MH thanks Universiti Sains Malaysia for a postdoctoral research fellowship.

References

Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19. CSD CrossRef Web of Science Google Scholar
Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105–107. CrossRef CAS Web of Science IUCr Journals Google Scholar
Crundwell, G., Meskill, T., Sayers, D. & Kantardjieff, K. (2002a). Acta Cryst. E58, o666–o667. Web of Science CSD CrossRef IUCr Journals Google Scholar
Crundwell, G., Meskill, T., Sayers, D. & Kantardjieff, K. (2002b). Acta Cryst. E58, o668–o670. Web of Science CSD CrossRef IUCr Journals Google Scholar
Crundwell, G., Sayers, D., Herron, S. R. & Kantardjieff, K. A. (2003). Acta Cryst. E59, o314–o315. Web of Science CSD CrossRef IUCr Journals Google Scholar
Flack, H. D. (1983). Acta Cryst. A39, 876–881. CrossRef CAS Web of Science IUCr Journals Google Scholar
Linehan, J., Crundwell, G., Herron, S. R. & Kantardjieff, K. A. (2003). Acta Cryst. E59, o466–o468. Web of Science CSD CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Shimon, L. J. W., Vaida, M., Frolow, F., Lahav, M., Leiserowitz, L., Weissinger-Lewin, Y. & McMullan, R. K. (1993). Faraday Discuss. 95, 307–327. CrossRef CAS Web of Science Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar
Stacy, V. L., Crundwell, G., Updegraff, J. B. III, Zeller, M. & Hunter, A. D. (2003). Acta Cryst. E59, o1812–o1813. Web of Science CSD CrossRef IUCr Journals Google Scholar