supplementary materials


xu2660 scheme

Acta Cryst. (2009). E65, o3003    [ doi:10.1107/S1600536809045917 ]

1,2-Bis(2-methyl-5-phenyl-3-thienyl)benzene

W.-J. Miao, L.-H. Li, S. Lu, G. Liu and C.-B. Fan

Abstract top

In the molecule of the title compound, C28H22S2, the two thiophene rings are twisted with respect to the central benzene ring, making dihedral angles of 71.59 (12) and 50.71 (12)°. The two terminal benzene rings are oriented at dihedral angles of 37.59 (11) and 20.12 (11)° to their bonded thiophene rings.

Comment top

The design and synthesis of photochromic molecules is an area of intense research because of the widespread use in photonic device applications such as memory media and optical switching (Irie et al. 2001). To date, four kinds of diarylethenes with different bridge units have been reported, that is diarylethenes with a perfluorocyclopentene moiety (Peters et al. 2003), diarylethenes with maleic anhydride and maleimide moieties (Yamaguchi et al. 1997), diarylethenes with a cyclopentene moiety (Lucas et al. 1998), and diarylethenes with a 2,5-dihydrothiphene moiety (Chen & Zeng, 2004). One of our research goals is to develop a novel diarylethene derivative with the inexpensive benzene ring as bridge unit. In this paper, the ORTEP drawing of the single-crystal shows the title compound, i.e. 1,2-(2-methyl-5-phenyl-3-thienyl)benzene, packed in a parallel conformation which is very rare in other diarylethene system. The two independent planar thiophene ring systems have essentially identical geometries, and the dihedral angles between the central benzene-ring and these of the two thiophene rings, S1/C7—C10, and S2/ C18—C21 are 71.6 (4)° and 50.5 (7)°. The two thiophene groups are linked by the central benzene-ring, with both of them attached to the ethylene group via the 2-position. The distance between the two C atoms (C8···C19) is 4.06 (7) Å, which is short enough, theoretically, for the ring-closure reaction to take place in the crystalline phase (Ramamurthy & Venkatesan, 1987), but the crystals of the title compound is parallel thiophene-ring, so, the crystals cannot show photochromism.

Related literature top

For the synthesis of the precursor, see: Irie et al. (2000). For applications of photochromic molecules, see: Irie et al. (2001). For diarylethenes with four different bridging units, see: Peters et al. (2003); Yamaguchi et al. (1997); Lucas et al. (1998); Chen & Zeng (2004). For ring-closure reactions, see: Ramamurthy & Venkatesan (1987). For a related structure, see: Pu et al. (2005).

Experimental top

2-Methyl-5-phenylthiophen-3-yl-3-boronic acid, (2) in Fig 2, was obtained in the presence of compound 3-bromo-2-methyl-5-phenylthiophene, (1), (Irie et al., 2000) (2.53 g, 10.00 mmol) in a n-BuLi/hexane solution (2.50 mol/L, 12.00 mmol) and tri-n-butylborate (2.76 g, 12.00 mmol) at 195 K under a nitrogen atmosphere.

The title compound was prepared by adding compound (2) (0.88 g, 4.05 mmol) with Na2CO3 (2.00 mol/L, 60.00 mmol) to a stirred THF solution (50 ml) containing 1,2-dibromobenzene (0.48 g, 2.03 mmol) and Pd(PPh3)4 (0.27 g) at 293 K under a nitrogen atmosphere. After reflux for 16 h, the reaction mixture was extracted with ether, evaporated in vacuo and purified by column chromatography on SiO2 using petroleum ether as the eluent to obtain the title compound. Single crystals of the title compound (1a) were grown from a chloroform solution by slow evaporation (m.p. 404.8–405.2 K).

Refinement top

H atoms were placed in calculated positions and treated as riding with C—H = 0.96 Å (methyl) or 0.93 Å (aromatic), Uiso(H) = 1.5Ueq(C) for methyl H atoms and Uiso(H) = 1.2Ueq(C) for the others.

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); 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).

Figures top
[Figure 1] Fig. 1. Molecular view the atom-labeling scheme. Ellipsoids are drawn at the 30% probability level. H atoms are represented as small spheres of arbitrary radii.
[Figure 2] Fig. 2. The preparation of the title compound.
1,2-Bis(2-methyl-5-phenyl-3-thienyl)benzene top
Crystal data top
C28H22S2Z = 2
Mr = 422.58F(000) = 444
Triclinic, P1Dx = 1.252 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 10.0934 (12) ÅCell parameters from 2224 reflections
b = 10.0945 (12) Åθ = 2.6–22.8°
c = 11.9565 (15) ŵ = 0.25 mm1
α = 83.803 (1)°T = 296 K
β = 67.769 (1)°Block, colourless
γ = 86.362 (1)°0.40 × 0.24 × 0.15 mm
V = 1120.7 (2) Å3
Data collection top
Bruker SMART CCD area-detector
diffractometer
4136 independent reflections
Radiation source: fine-focus sealed tube2920 reflections with I > 2σ(I)
graphiteRint = 0.021
φ and ω scansθmax = 25.5°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 1212
Tmin = 0.907, Tmax = 0.964k = 1212
8610 measured reflectionsl = 1414
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)] = 0.041Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.108H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0442P)2 + 0.2296P]
where P = (Fo2 + 2Fc2)/3
4136 reflections(Δ/σ)max = 0.006
273 parametersΔρmax = 0.18 e Å3
0 restraintsΔρmin = 0.17 e Å3
Crystal data top
C28H22S2γ = 86.362 (1)°
Mr = 422.58V = 1120.7 (2) Å3
Triclinic, P1Z = 2
a = 10.0934 (12) ÅMo Kα radiation
b = 10.0945 (12) ŵ = 0.25 mm1
c = 11.9565 (15) ÅT = 296 K
α = 83.803 (1)°0.40 × 0.24 × 0.15 mm
β = 67.769 (1)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
4136 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2920 reflections with I > 2σ(I)
Tmin = 0.907, Tmax = 0.964Rint = 0.021
8610 measured reflectionsθmax = 25.5°
Refinement top
R[F2 > 2σ(F2)] = 0.041H-atom parameters constrained
wR(F2) = 0.108Δρmax = 0.18 e Å3
S = 1.02Δρmin = 0.17 e Å3
4136 reflectionsAbsolute structure: ?
273 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

Experimental. 1HNMR (400 MHz, CDCl3, TMS): δ 2.17 (s, 3H, -CH3), 6.92 (s, 1H, thienyl-H), 7.20 (t, 1H, J=7.2 Hz,phenyl-H), 7.29 (t, 2H, J=7.4 Hz, phenyl-H), 7.42–7.44 (m, 4H, phenyl-H). 13C NMR (100 MHz, CDCl3): δ 13.93, 125.51, 126.00, 127.00, 127.26, 128.76, 130.61, 134.60, 135.03, 136.09, 139.01, 139.45. IR (KBr, cm-1): 756, 766, 849, 908, 946, 1001, 1029, 1073, 1153, 1184, 1227, 1377, 1462, 1479, 1505, 1596, 1629, 2854, 2924, 3014, 3053, 3254, 3443, 3529, 3676.

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
C10.8690 (3)0.1761 (2)0.33341 (19)0.0593 (6)
C21.0178 (3)0.1571 (2)0.27841 (19)0.0632 (6)
C31.0724 (3)0.0279 (3)0.2524 (2)0.0837 (8)
H31.17080.01370.21600.100*
C40.9833 (5)0.0781 (3)0.2798 (3)0.1002 (11)
H41.02170.16330.26340.120*
C50.8382 (5)0.0587 (3)0.3312 (3)0.0994 (11)
H50.77800.13030.34780.119*
C60.7806 (3)0.0679 (2)0.3587 (2)0.0803 (7)
H60.68190.08030.39440.096*
C70.8057 (2)0.3112 (2)0.36380 (18)0.0534 (5)
C80.8183 (2)0.3757 (2)0.45372 (19)0.0564 (5)
C90.6907 (2)0.5132 (2)0.33745 (18)0.0517 (5)
C100.7318 (2)0.3902 (2)0.29899 (19)0.0563 (5)
H100.71330.36020.23570.068*
C110.8878 (3)0.3254 (3)0.5415 (2)0.0791 (7)
H11A0.90790.23150.53700.119*
H11B0.82450.34140.62230.119*
H11C0.97550.37120.52140.119*
C120.6259 (2)0.6253 (2)0.28537 (19)0.0535 (5)
C130.6640 (2)0.6476 (2)0.1601 (2)0.0626 (6)
H130.72770.58900.10950.075*
C140.6079 (3)0.7558 (3)0.1111 (3)0.0798 (7)
H140.63390.77030.02740.096*
C150.5132 (3)0.8426 (3)0.1857 (3)0.0821 (8)
H150.47650.91630.15230.099*
C160.4735 (3)0.8211 (3)0.3071 (3)0.0855 (8)
H160.40770.87910.35680.103*
C170.5293 (2)0.7141 (2)0.3585 (2)0.0692 (6)
H170.50220.70130.44240.083*
C181.1146 (2)0.2710 (2)0.24104 (19)0.0586 (6)
C191.2360 (3)0.2804 (2)0.2660 (2)0.0659 (6)
C201.1898 (2)0.4834 (2)0.14581 (18)0.0552 (5)
C211.0915 (2)0.3879 (2)0.17170 (18)0.0554 (5)
H211.01480.39780.14620.066*
C221.2975 (3)0.1831 (3)0.3393 (3)0.0933 (9)
H22A1.22550.12130.38910.140*
H22B1.32860.23060.38990.140*
H22C1.37750.13540.28550.140*
C231.1947 (2)0.6143 (2)0.07776 (19)0.0567 (5)
C241.3183 (3)0.6851 (3)0.0253 (3)0.0844 (8)
H241.40200.64920.03270.101*
C251.3216 (4)0.8071 (3)0.0376 (3)0.1023 (10)
H251.40680.85290.07190.123*
C261.2003 (4)0.8618 (3)0.0504 (2)0.0908 (9)
H261.20250.94520.09260.109*
C271.0761 (4)0.7937 (3)0.0010 (2)0.0833 (8)
H270.99360.82980.01080.100*
C281.0726 (3)0.6706 (2)0.0638 (2)0.0664 (6)
H280.98710.62520.09840.080*
S10.74075 (6)0.53246 (6)0.45767 (5)0.06329 (19)
S21.31728 (6)0.43038 (7)0.20603 (6)0.0720 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0884 (17)0.0445 (12)0.0466 (12)0.0012 (11)0.0277 (12)0.0017 (9)
C20.0946 (18)0.0483 (13)0.0484 (12)0.0156 (12)0.0301 (12)0.0083 (10)
C30.131 (2)0.0569 (16)0.0672 (16)0.0299 (16)0.0444 (16)0.0162 (13)
C40.188 (4)0.0461 (16)0.081 (2)0.021 (2)0.068 (2)0.0143 (14)
C50.184 (4)0.0475 (16)0.080 (2)0.023 (2)0.066 (2)0.0057 (14)
C60.118 (2)0.0591 (16)0.0649 (16)0.0183 (15)0.0345 (15)0.0021 (12)
C70.0589 (13)0.0478 (12)0.0491 (12)0.0035 (10)0.0159 (10)0.0009 (9)
C80.0610 (13)0.0558 (13)0.0527 (12)0.0030 (10)0.0217 (10)0.0075 (10)
C90.0501 (11)0.0513 (12)0.0501 (12)0.0015 (9)0.0141 (9)0.0067 (10)
C100.0634 (13)0.0543 (13)0.0525 (12)0.0050 (10)0.0219 (11)0.0085 (10)
C110.0984 (19)0.0797 (17)0.0720 (16)0.0163 (15)0.0466 (15)0.0164 (13)
C120.0456 (11)0.0528 (12)0.0599 (13)0.0046 (9)0.0166 (10)0.0054 (10)
C130.0586 (13)0.0684 (15)0.0603 (14)0.0055 (11)0.0224 (11)0.0072 (11)
C140.0778 (17)0.0892 (19)0.0730 (17)0.0020 (15)0.0326 (14)0.0068 (15)
C150.0871 (19)0.0654 (16)0.090 (2)0.0093 (14)0.0358 (16)0.0098 (15)
C160.0881 (19)0.0652 (17)0.091 (2)0.0222 (14)0.0230 (16)0.0115 (15)
C170.0703 (15)0.0608 (15)0.0668 (15)0.0054 (12)0.0164 (12)0.0032 (12)
C180.0679 (14)0.0547 (13)0.0486 (12)0.0163 (11)0.0177 (11)0.0113 (10)
C190.0751 (15)0.0671 (15)0.0543 (13)0.0249 (12)0.0247 (12)0.0144 (11)
C200.0573 (13)0.0598 (13)0.0472 (12)0.0106 (11)0.0181 (10)0.0116 (10)
C210.0596 (13)0.0561 (13)0.0490 (12)0.0106 (11)0.0195 (10)0.0081 (10)
C220.115 (2)0.0891 (19)0.0877 (19)0.0411 (17)0.0562 (18)0.0157 (15)
C230.0633 (14)0.0582 (13)0.0478 (12)0.0019 (11)0.0185 (11)0.0124 (10)
C240.0715 (17)0.0837 (19)0.092 (2)0.0104 (14)0.0261 (15)0.0034 (16)
C250.107 (2)0.086 (2)0.100 (2)0.0264 (19)0.025 (2)0.0139 (18)
C260.149 (3)0.0630 (17)0.0606 (16)0.011 (2)0.0398 (19)0.0025 (13)
C270.114 (2)0.0696 (17)0.0803 (18)0.0118 (17)0.0540 (18)0.0101 (14)
C280.0756 (16)0.0585 (14)0.0708 (15)0.0037 (12)0.0347 (13)0.0059 (12)
S10.0722 (4)0.0584 (4)0.0657 (4)0.0089 (3)0.0312 (3)0.0185 (3)
S20.0651 (4)0.0846 (5)0.0711 (4)0.0146 (3)0.0318 (3)0.0135 (3)
Geometric parameters (Å, °) top
C1—C61.389 (3)C14—H140.9300
C1—C21.403 (3)C15—C161.348 (4)
C1—C71.490 (3)C15—H150.9300
C2—C31.403 (3)C16—C171.380 (3)
C2—C181.475 (3)C16—H160.9300
C3—C41.373 (4)C17—H170.9300
C3—H30.9300C18—C191.377 (3)
C4—C51.367 (4)C18—C211.427 (3)
C4—H40.9300C19—C221.505 (3)
C5—C61.390 (4)C19—S21.720 (3)
C5—H50.9300C20—C211.354 (3)
C6—H60.9300C20—C231.468 (3)
C7—C81.364 (3)C20—S21.730 (2)
C7—C101.422 (3)C21—H210.9300
C8—C111.500 (3)C22—H22A0.9600
C8—S11.718 (2)C22—H22B0.9600
C9—C101.356 (3)C22—H22C0.9600
C9—C121.469 (3)C23—C241.373 (3)
C9—S11.727 (2)C23—C281.384 (3)
C10—H100.9300C24—C251.367 (4)
C11—H11A0.9600C24—H240.9300
C11—H11B0.9600C25—C261.366 (4)
C11—H11C0.9600C25—H250.9300
C12—C171.390 (3)C26—C271.362 (4)
C12—C131.394 (3)C26—H260.9300
C13—C141.375 (3)C27—C281.388 (3)
C13—H130.9300C27—H270.9300
C14—C151.376 (4)C28—H280.9300
C6—C1—C2119.4 (2)C16—C15—H15119.9
C6—C1—C7120.1 (2)C14—C15—H15119.9
C2—C1—C7120.50 (19)C15—C16—C17120.8 (2)
C1—C2—C3118.4 (2)C15—C16—H16119.6
C1—C2—C18121.09 (18)C17—C16—H16119.6
C3—C2—C18120.4 (2)C16—C17—C12120.1 (2)
C4—C3—C2121.2 (3)C16—C17—H17119.9
C4—C3—H3119.4C12—C17—H17119.9
C2—C3—H3119.4C19—C18—C21111.2 (2)
C5—C4—C3120.2 (3)C19—C18—C2126.3 (2)
C5—C4—H4119.9C21—C18—C2122.4 (2)
C3—C4—H4119.9C18—C19—C22129.2 (2)
C4—C5—C6120.1 (3)C18—C19—S2111.29 (17)
C4—C5—H5120.0C22—C19—S2119.5 (2)
C6—C5—H5120.0C21—C20—C23127.9 (2)
C1—C6—C5120.7 (3)C21—C20—S2109.85 (16)
C1—C6—H6119.7C23—C20—S2122.28 (18)
C5—C6—H6119.7C20—C21—C18114.9 (2)
C8—C7—C10112.25 (19)C20—C21—H21122.5
C8—C7—C1123.57 (19)C18—C21—H21122.5
C10—C7—C1124.11 (19)C19—C22—H22A109.5
C7—C8—C11128.1 (2)C19—C22—H22B109.5
C7—C8—S1110.85 (16)H22A—C22—H22B109.5
C11—C8—S1121.04 (16)C19—C22—H22C109.5
C10—C9—C12129.5 (2)H22A—C22—H22C109.5
C10—C9—S1109.77 (16)H22B—C22—H22C109.5
C12—C9—S1120.54 (15)C24—C23—C28117.4 (2)
C9—C10—C7114.25 (19)C24—C23—C20122.3 (2)
C9—C10—H10122.9C28—C23—C20120.3 (2)
C7—C10—H10122.9C25—C24—C23121.8 (3)
C8—C11—H11A109.5C25—C24—H24119.1
C8—C11—H11B109.5C23—C24—H24119.1
H11A—C11—H11B109.5C26—C25—C24120.3 (3)
C8—C11—H11C109.5C26—C25—H25119.9
H11A—C11—H11C109.5C24—C25—H25119.9
H11B—C11—H11C109.5C27—C26—C25119.6 (3)
C17—C12—C13118.3 (2)C27—C26—H26120.2
C17—C12—C9121.3 (2)C25—C26—H26120.2
C13—C12—C9120.39 (19)C26—C27—C28120.0 (3)
C14—C13—C12120.4 (2)C26—C27—H27120.0
C14—C13—H13119.8C28—C27—H27120.0
C12—C13—H13119.8C23—C28—C27120.9 (2)
C13—C14—C15120.0 (2)C23—C28—H28119.6
C13—C14—H14120.0C27—C28—H28119.6
C15—C14—H14120.0C8—S1—C992.87 (10)
C16—C15—C14120.3 (2)C19—S2—C2092.73 (11)
C6—C1—C2—C31.0 (3)C9—C12—C17—C16177.9 (2)
C7—C1—C2—C3179.48 (19)C1—C2—C18—C19131.3 (2)
C6—C1—C2—C18175.0 (2)C3—C2—C18—C1952.8 (3)
C7—C1—C2—C184.6 (3)C1—C2—C18—C2148.9 (3)
C1—C2—C3—C40.0 (3)C3—C2—C18—C21126.9 (2)
C18—C2—C3—C4176.0 (2)C21—C18—C19—C22177.8 (2)
C2—C3—C4—C51.3 (4)C2—C18—C19—C222.4 (4)
C3—C4—C5—C61.6 (4)C21—C18—C19—S20.5 (2)
C2—C1—C6—C50.7 (3)C2—C18—C19—S2179.78 (16)
C7—C1—C6—C5179.8 (2)C23—C20—C21—C18179.37 (19)
C4—C5—C6—C10.6 (4)S2—C20—C21—C180.6 (2)
C6—C1—C7—C8110.3 (3)C19—C18—C21—C200.7 (3)
C2—C1—C7—C870.1 (3)C2—C18—C21—C20179.54 (18)
C6—C1—C7—C1073.0 (3)C21—C20—C23—C24159.5 (2)
C2—C1—C7—C10106.6 (2)S2—C20—C23—C2420.6 (3)
C10—C7—C8—C11179.6 (2)C21—C20—C23—C2820.2 (3)
C1—C7—C8—C113.3 (4)S2—C20—C23—C28159.79 (17)
C10—C7—C8—S10.4 (2)C28—C23—C24—C250.5 (4)
C1—C7—C8—S1176.70 (17)C20—C23—C24—C25179.8 (3)
C12—C9—C10—C7173.27 (19)C23—C24—C25—C260.3 (5)
S1—C9—C10—C71.0 (2)C24—C25—C26—C270.6 (5)
C8—C7—C10—C90.9 (3)C25—C26—C27—C281.2 (4)
C1—C7—C10—C9176.1 (2)C24—C23—C28—C270.1 (3)
C10—C9—C12—C17147.8 (2)C20—C23—C28—C27179.5 (2)
S1—C9—C12—C1738.5 (3)C26—C27—C28—C231.0 (4)
C10—C9—C12—C1334.4 (3)C7—C8—S1—C90.15 (17)
S1—C9—C12—C13139.39 (18)C11—C8—S1—C9179.88 (19)
C17—C12—C13—C140.7 (3)C10—C9—S1—C80.66 (17)
C9—C12—C13—C14177.3 (2)C12—C9—S1—C8174.21 (17)
C12—C13—C14—C150.2 (4)C18—C19—S2—C200.12 (17)
C13—C14—C15—C160.9 (4)C22—C19—S2—C20177.74 (19)
C14—C15—C16—C171.6 (4)C21—C20—S2—C190.27 (16)
C15—C16—C17—C121.1 (4)C23—C20—S2—C19179.69 (17)
C13—C12—C17—C160.0 (3)
Acknowledgements top

This work was supported by the Science Fund of the Education Office of Jiangxi (GJJ09306, GJJ09302) and the Youth Science Fund of the Education Office of Jiangxi (GJJ09572).

references
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