4,4′-Bis[2-(3,4-dibutyl-2-thienylethyn­yl)]biphen­yl

Liu, L.; Liu, N.; Xu, W.; Zhu, D.-B.

doi:10.1107/S1600536808036143

organic compounds

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ISSN: 2056-9890

Volume 64| Part 12| December 2008| Page o2306

doi:10.1107/S1600536808036143

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4,4′-Bis[2-(3,4-dibutyl-2-thienylethynyl)]biphenyl

Lei Liu,^a ^* Na Liu,^b Wei Xu ^c and Dao-Ben Zhu ^b

^aCollege of Chemical and Pharmaceutical Engineering, Hebei University of Science and Technology, Shijiazhuang, Hebei 050018, People's Republic of China, ^bCollege of Bioscience and Biotechnology, Hunan Agricultural University, Hanan 410128, People's Republic of China, and ^c106 Group, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, People's Republic of China
^*Correspondence e-mail: liulei@iccas.ac.cn

(Received 11 August 2008; accepted 4 November 2008; online 13 November 2008)

The molecule of the title compound, C₄₀H₄₆S₂, reveals C_i symmetry. An inversion centre is located at the mid-point of the C—C bond of the biphenyl unit; the asymmetric unit comprises one-half of the molecule. The conjugated backbone is nearly planar, with a mean deviation of 0.041 Å.

Related literature

For general background, see: Brad Wan et al. (2000 ); Cornil et al. (2001 ); Grosshenny et al. (1997 ); Huang & Tour (1998 ); Tour (1996 ). For related structures, see: Baudour (1972 ); Charbonneau & Delugeard (1977 ); Domenicano et al. (1975 ); Robertson (1961 ). For the synthesis, see: Liu et al. (2005 ).

Experimental

Crystal data

C₄₀H₄₆S₂
M_r = 590.89
Triclinic, $[P \overline 1]$
a = 9.2040 (18) Å
b = 9.3640 (19) Å
c = 10.582 (2) Å
α = 85.69 (3)°
β = 85.18 (3)°
γ = 69.41 (3)°
V = 849.7 (3) Å³
Z = 1
Mo Kα radiation
μ = 0.18 mm⁻¹
T = 293 (2) K
0.62 × 0.40 × 0.07 mm

Data collection

Rigaku R-AXIS RAPID IP diffractometer
Absorption correction: empirical (using intensity measurements) (ABSCOR; Higashi, 1995 ) T_min = 0.805, T_max = 0.992
3595 measured reflections
3595 independent reflections
2287 reflections with I > 2σ(I)

Refinement

R[F² > 2σ(F²)] = 0.067
wR(F²) = 0.241
S = 1.07
3595 reflections
190 parameters
H-atom parameters constrained
Δρ_max = 0.44 e Å⁻³
Δρ_min = −0.42 e Å⁻³

Data collection: RAPID-AUTO (Rigaku, 2001 ); cell refinement: RAPID-AUTO; data reduction: RAPID-AUTO; 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: SHELXTL.

Supporting information

Crystal structure: contains datablocks 070712a, I. DOI: 10.1107/S1600536808036143/kp2189sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808036143/kp2189Isup2.hkl

checkCIF report

Comment top

The synthesis and characterization of nanometer-sized conjugated molecules of precise length and constitution are of widespread interest, which is due to their electroconductive, magnetic, and optical properties (Tour, 1996; Huang & Tour, 1998; Grosshenny et al., 1997; Brad Wan et al., 2000). Generally, crystal structure of a molecule is important for better understanding of its properties. Therefore, structures of oligothiophene single crystals have been reported. The field of molecular organic semiconductors is being revolutionized by the availability of ultrahigh purity single crystals that have allowed the demonstration of phenomena long thought to be restricted to inorganic semiconductors (Cornil et al., 2001).

The molecule of the title compound (Fig. 1) is centrosymmetric. An asymmetric unit comprises a half on the molecule. The inversion centre is located in the middle of C3—C3i bond. Conjugated molecular skeleton is nearly planar; mean deviation from the best least-square plane is 0.041 Å. The endocyclic bond angles on the long molecular axis are less than the normal 120° value (they vary from 116.42–117.52°) whereas that situated out of this long molecular axis are greater than 120° (in the range 120.73–122.43°). This result agrees with those obtained for polyphenyls (Robertson, 1961; Baudour, 1972; Domenicano et al., 1975; Charbonneau & Delugeard, 1977). The two thiophene rings, phenyl rings and C≡C are coplanar. The crystal packing is dominated by van der Waals interactions.

Related literature top

For related literature, see: Baudour (1972); Brad Wan et al. (2000); Charbonneau & Delugeard (1977); Cornil et al. (2001); Domenicano et al. (1975); Grosshenny et al. (1997); Huang & Tour (1998); Liu et al. (2005); Robertson (1961); Tour (1996). It would be much more useful to readers if the "Related literature" section had some kind of simple sub-division, so that, instead of just "For related literature, see···" it said, for example, "For general background, see···. For related structures, see···; etc. Please revise this section as indicated.

Experimental top

The synthesis of 4,4'-bis-[2-(3,4-dibutyl-2-thienylethynyl)]biphenyl was performed as previously described (Liu et al., 2005).

Yellow needles were grown from an ethanol/hexane solution by slow evaporation.

Computing details top

Data collection: RAPID-AUTO (Rigaku, 2001); cell refinement: RAPID-AUTO (Rigaku, 2001); data reduction: RAPID-AUTO (Rigaku, 2001); 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: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. View of the title compound, showing the atom-labelling scheme and displacement ellipsoids at the 50% probability. To generate the molecule symmetry code -x, -y, -z + 2 is applied.
	Fig. 2. View of the packing mode along a axis of (I).

4,4'-Bis[2-(3,4-dibutyl-2-thienylethynyl)]biphenyl top

Crystal data top

C₄₀H₄₆S₂	V = 849.7 (3) Å³
M_r = 590.89	Z = 1
Triclinic, P1	F(000) = 318
a = 9.2040 (18) Å	D_x = 1.155 Mg m⁻³
b = 9.3640 (19) Å	Mo Kα radiation, λ = 0.71073 Å
c = 10.582 (2) Å	µ = 0.18 mm⁻¹
α = 85.69 (3)°	T = 293 K
β = 85.18 (3)°	Neddle, yellow
γ = 69.41 (3)°	0.62 × 0.40 × 0.07 mm

Data collection top

Rigaku R-AXIS RAPID IP diffractometer	3595 independent reflections
Radiation source: fine-focus sealed tube	2287 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.000
Detector resolution: 0.76 pixels mm^-1	θ_max = 27.5°, θ_min = 2.3°
Oscillation scans	h = 0→11
Absorption correction: empirical (using intensity measurements) (ABSCOR; Higashi, 1995)	k = −10→12
T_min = 0.805, T_max = 0.992	l = −13→13
3595 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.067	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.241	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.1672P)² + 0.1626P] where P = (F_o² + 2F_c²)/3
3595 reflections	(Δ/σ)_max < 0.001
190 parameters	Δρ_max = 0.44 e Å⁻³
0 restraints	Δρ_min = −0.42 e Å⁻³

Crystal data top

C₄₀H₄₆S₂	γ = 69.41 (3)°
M_r = 590.89	V = 849.7 (3) Å³
Triclinic, P1	Z = 1
a = 9.2040 (18) Å	Mo Kα radiation
b = 9.3640 (19) Å	µ = 0.18 mm⁻¹
c = 10.582 (2) Å	T = 293 K
α = 85.69 (3)°	0.62 × 0.40 × 0.07 mm
β = 85.18 (3)°

Data collection top

Rigaku R-AXIS RAPID IP diffractometer	3595 independent reflections
Absorption correction: empirical (using intensity measurements) (ABSCOR; Higashi, 1995)	2287 reflections with I > 2σ(I)
T_min = 0.805, T_max = 0.992	R_int = 0.000
3595 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.067	0 restraints
wR(F²) = 0.241	H-atom parameters constrained
S = 1.07	Δρ_max = 0.44 e Å⁻³
3595 reflections	Δρ_min = −0.42 e Å⁻³
190 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

	x	y	z	U_iso*/U_eq
S1	0.34733 (8)	0.37884 (8)	0.02833 (7)	0.0512 (3)
C1	−0.2000 (4)	0.5223 (4)	0.3588 (3)	0.0657 (9)
H1A	−0.1334	0.5778	0.3558	0.079*
C2	−0.3290 (4)	0.5588 (4)	0.4443 (3)	0.0615 (8)
H2A	−0.3467	0.6388	0.4973	0.074*
C3	−0.4314 (3)	0.4808 (3)	0.4534 (2)	0.0393 (5)
C4	−0.4016 (4)	0.3655 (4)	0.3702 (4)	0.0750 (12)
H4A	−0.4696	0.3116	0.3721	0.090*
C5	−0.2733 (4)	0.3276 (5)	0.2840 (4)	0.0816 (13)
H5A	−0.2573	0.2494	0.2295	0.098*
C6	−0.1694 (3)	0.4041 (3)	0.2779 (2)	0.0439 (6)
C7	−0.0335 (3)	0.3631 (3)	0.1922 (3)	0.0476 (6)
C8	0.0798 (3)	0.3289 (3)	0.1211 (2)	0.0440 (6)
C9	0.2138 (3)	0.2853 (3)	0.0369 (2)	0.0415 (6)
C10	0.2565 (3)	0.1695 (3)	−0.0473 (2)	0.0387 (5)
C11	0.3994 (3)	0.1568 (3)	−0.1180 (2)	0.0419 (6)
C12	0.4587 (3)	0.2635 (3)	−0.0862 (3)	0.0497 (7)
H12	0.5507	0.2720	−0.1235	0.060*
C13	0.1620 (3)	0.0701 (3)	−0.0634 (3)	0.0463 (6)
H13A	0.0948	0.0719	0.0126	0.056*
H13B	0.2317	−0.0344	−0.0728	0.056*
C14	0.4717 (3)	0.0371 (3)	−0.2152 (3)	0.0515 (7)
H14A	0.4910	−0.0630	−0.1731	0.062*
H14B	0.3969	0.0498	−0.2784	0.062*
C15	0.0618 (3)	0.1215 (3)	−0.1791 (3)	0.0503 (6)
H15A	0.1267	0.1352	−0.2527	0.060*
H15B	0.0233	0.0412	−0.1960	0.060*
C16	0.6214 (3)	0.0406 (3)	−0.2825 (3)	0.0498 (7)
H16A	0.6965	0.0293	−0.2201	0.060*
H16B	0.6025	0.1390	−0.3274	0.060*
C17	−0.0748 (3)	0.2680 (4)	−0.1618 (3)	0.0575 (7)
H17A	−0.0376	0.3445	−0.1336	0.069*
H17B	−0.1465	0.2501	−0.0953	0.069*
C18	0.6894 (3)	−0.0855 (4)	−0.3767 (3)	0.0604 (8)
H18A	0.7095	−0.1838	−0.3314	0.073*
H18B	0.6131	−0.0752	−0.4380	0.073*
C19	−0.1626 (4)	0.3311 (4)	−0.2807 (3)	0.0680 (9)
H19A	−0.2477	0.4233	−0.2623	0.102*
H19B	−0.2019	0.2571	−0.3085	0.102*
H19C	−0.0936	0.3526	−0.3464	0.102*
C20	0.8373 (5)	−0.0823 (6)	−0.4465 (4)	0.0866 (13)
H20A	0.8747	−0.1641	−0.5037	0.130*
H20B	0.9140	−0.0944	−0.3866	0.130*
H20C	0.8177	0.0135	−0.4937	0.130*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0432 (4)	0.0556 (4)	0.0568 (5)	−0.0203 (3)	0.0164 (3)	−0.0206 (3)
C1	0.0576 (17)	0.080 (2)	0.070 (2)	−0.0398 (16)	0.0352 (15)	−0.0323 (17)
C2	0.0596 (17)	0.0696 (18)	0.0622 (18)	−0.0334 (15)	0.0336 (14)	−0.0329 (15)
C3	0.0314 (11)	0.0457 (12)	0.0341 (11)	−0.0071 (9)	0.0110 (9)	−0.0058 (9)
C4	0.0615 (18)	0.088 (2)	0.090 (2)	−0.0447 (18)	0.0481 (18)	−0.055 (2)
C5	0.068 (2)	0.090 (2)	0.097 (3)	−0.0424 (19)	0.054 (2)	−0.062 (2)
C6	0.0326 (11)	0.0505 (14)	0.0415 (13)	−0.0084 (10)	0.0130 (10)	−0.0066 (10)
C7	0.0395 (13)	0.0532 (14)	0.0433 (14)	−0.0099 (11)	0.0122 (11)	−0.0087 (11)
C8	0.0372 (12)	0.0506 (14)	0.0393 (13)	−0.0113 (11)	0.0109 (10)	−0.0059 (10)
C9	0.0326 (11)	0.0477 (13)	0.0404 (12)	−0.0116 (10)	0.0126 (10)	−0.0065 (10)
C10	0.0321 (11)	0.0443 (12)	0.0366 (12)	−0.0116 (9)	0.0080 (9)	−0.0025 (9)
C11	0.0315 (11)	0.0488 (13)	0.0406 (13)	−0.0098 (10)	0.0118 (9)	−0.0082 (10)
C12	0.0360 (12)	0.0596 (15)	0.0526 (15)	−0.0182 (11)	0.0201 (11)	−0.0148 (12)
C13	0.0430 (13)	0.0452 (13)	0.0514 (14)	−0.0190 (11)	0.0110 (11)	−0.0048 (11)
C14	0.0385 (13)	0.0582 (16)	0.0552 (16)	−0.0142 (12)	0.0173 (11)	−0.0212 (13)
C15	0.0452 (13)	0.0580 (15)	0.0509 (15)	−0.0225 (12)	0.0100 (11)	−0.0140 (12)
C16	0.0374 (13)	0.0617 (16)	0.0442 (14)	−0.0113 (12)	0.0149 (11)	−0.0129 (12)
C17	0.0475 (15)	0.0641 (18)	0.0589 (17)	−0.0165 (13)	0.0028 (13)	−0.0116 (14)
C18	0.0478 (15)	0.077 (2)	0.0428 (15)	−0.0039 (14)	0.0070 (12)	−0.0187 (14)
C19	0.0546 (18)	0.080 (2)	0.068 (2)	−0.0214 (17)	−0.0071 (15)	−0.0038 (17)
C20	0.063 (2)	0.111 (3)	0.061 (2)	−0.003 (2)	0.0313 (17)	−0.018 (2)

Geometric parameters (Å, º) top

S1—C12	1.702 (3)	C13—H13A	0.9700
S1—C9	1.735 (3)	C13—H13B	0.9700
C1—C6	1.385 (4)	C14—C16	1.507 (3)
C1—C2	1.387 (4)	C14—H14A	0.9700
C1—H1A	0.9300	C14—H14B	0.9700
C2—C3	1.375 (4)	C15—C17	1.511 (4)
C2—H2A	0.9300	C15—H15A	0.9700
C3—C4	1.382 (4)	C15—H15B	0.9700
C3—C3ⁱ	1.490 (4)	C16—C18	1.527 (4)
C4—C5	1.387 (4)	C16—H16A	0.9700
C4—H4A	0.9300	C16—H16B	0.9700
C5—C6	1.377 (4)	C17—C19	1.519 (5)
C5—H5A	0.9300	C17—H17A	0.9700
C6—C7	1.435 (3)	C17—H17B	0.9700
C7—C8	1.193 (3)	C18—C20	1.502 (5)
C8—C9	1.414 (3)	C18—H18A	0.9700
C9—C10	1.382 (3)	C18—H18B	0.9700
C10—C11	1.428 (3)	C19—H19A	0.9600
C10—C13	1.507 (4)	C19—H19B	0.9600
C11—C12	1.369 (4)	C19—H19C	0.9600
C11—C14	1.514 (3)	C20—H20A	0.9600
C12—H12	0.9300	C20—H20B	0.9600
C13—C15	1.539 (4)	C20—H20C	0.9600

C12—S1—C9	91.29 (12)	C11—C14—H14A	108.5
C6—C1—C2	120.7 (3)	C16—C14—H14B	108.5
C6—C1—H1A	119.7	C11—C14—H14B	108.5
C2—C1—H1A	119.7	H14A—C14—H14B	107.5
C3—C2—C1	122.4 (3)	C17—C15—C13	113.7 (2)
C3—C2—H2A	118.8	C17—C15—H15A	108.8
C1—C2—H2A	118.8	C13—C15—H15A	108.8
C2—C3—C4	116.4 (2)	C17—C15—H15B	108.8
C2—C3—C3ⁱ	122.1 (3)	C13—C15—H15B	108.8
C4—C3—C3ⁱ	121.5 (3)	H15A—C15—H15B	107.7
C3—C4—C5	122.0 (3)	C14—C16—C18	112.4 (2)
C3—C4—H4A	119.0	C14—C16—H16A	109.1
C5—C4—H4A	119.0	C18—C16—H16A	109.1
C6—C5—C4	121.1 (3)	C14—C16—H16B	109.1
C6—C5—H5A	119.5	C18—C16—H16B	109.1
C4—C5—H5A	119.5	H16A—C16—H16B	107.9
C5—C6—C1	117.5 (2)	C15—C17—C19	114.3 (3)
C5—C6—C7	121.7 (2)	C15—C17—H17A	108.7
C1—C6—C7	120.8 (2)	C19—C17—H17A	108.7
C8—C7—C6	179.8 (4)	C15—C17—H17B	108.7
C7—C8—C9	178.8 (3)	C19—C17—H17B	108.7
C10—C9—C8	126.9 (2)	H17A—C17—H17B	107.6
C10—C9—S1	111.52 (17)	C20—C18—C16	113.2 (3)
C8—C9—S1	121.6 (2)	C20—C18—H18A	108.9
C9—C10—C11	112.0 (2)	C16—C18—H18A	108.9
C9—C10—C13	123.8 (2)	C20—C18—H18B	108.9
C11—C10—C13	124.2 (2)	C16—C18—H18B	108.9
C12—C11—C10	111.9 (2)	H18A—C18—H18B	107.7
C12—C11—C14	126.0 (2)	C17—C19—H19A	109.5
C10—C11—C14	122.0 (2)	C17—C19—H19B	109.5
C11—C12—S1	113.24 (18)	H19A—C19—H19B	109.5
C11—C12—H12	123.4	C17—C19—H19C	109.5
S1—C12—H12	123.4	H19A—C19—H19C	109.5
C10—C13—C15	112.8 (2)	H19B—C19—H19C	109.5
C10—C13—H13A	109.0	C18—C20—H20A	109.5
C15—C13—H13A	109.0	C18—C20—H20B	109.5
C10—C13—H13B	109.0	H20A—C20—H20B	109.5
C15—C13—H13B	109.0	C18—C20—H20C	109.5
H13A—C13—H13B	107.8	H20A—C20—H20C	109.5
C16—C14—C11	115.3 (2)	H20B—C20—H20C	109.5
C16—C14—H14A	108.5

C12—C11—C10—C9	−0.6 (4)	C4—C5—C6—C1	−1.5 (1)
C12—S1—C9—C10	0.1 (8)	C1—C2—C3—C4	−1.6 (1)
C10—C11—C12—S1	0.5 (1)	C5—C4—C3—C2	1.5 (1)
C11—C12—S1—C9	−0.2 (1)	C5—C6—C1—C2	1.4 (2)
C11—C10—C9—S1	0.4 (9)	C9—C8—C7—C6	93.5 (2)
C11—C10—C9—C8	−179.9 (8)	C10—C9—C8—C7	24.6 (9)
C12—S1—C9—C8	−179.7 (4)	S1—C9—C8—C7	−155.8 (2)
C7—C6—C5—C4	177.9 (5)	C5—C6—C7—C8	−117.5 (4)
C7—C6—C1—C2	−178.0 (5)	C1—C6—C7—C8	61.9 (1)
C6—C5—C4—C3	0.0 (4)	C4—C3—C3—C4	90.0 (1)
C6—C1—C2—C3	0.1 (5)

Symmetry code: (i) −x−1, −y+1, −z+1.

Experimental details

Crystal data
Chemical formula	C₄₀H₄₆S₂
M_r	590.89
Crystal system, space group	Triclinic, P1
Temperature (K)	293
a, b, c (Å)	9.2040 (18), 9.3640 (19), 10.582 (2)
α, β, γ (°)	85.69 (3), 85.18 (3), 69.41 (3)
V (Å³)	849.7 (3)
Z	1
Radiation type	Mo Kα
µ (mm⁻¹)	0.18
Crystal size (mm)	0.62 × 0.40 × 0.07

Data collection
Diffractometer	Rigaku R-AXIS RAPID IP diffractometer
Absorption correction	Empirical (using intensity measurements) (ABSCOR; Higashi, 1995)
T_min, T_max	0.805, 0.992
No. of measured, independent and observed [I > 2σ(I)] reflections	3595, 3595, 2287
R_int	0.000
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.067, 0.241, 1.07
No. of reflections	3595
No. of parameters	190
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.44, −0.42

Computer programs: RAPID-AUTO (Rigaku, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Acknowledgements

The present research work was financially supported by the National Natural Science Foundation of China (grant No. 20572113), Hebei Natural Science Foundation, and the Hebei University of Science and Technology Project for Young Scientists Fund.

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