2-(9H-Fluoren-9-ylidenemeth­yl)thio­phene

Perašínová, L.; Štefko, M.; Végh, D.; Kožíšek, J.

doi:10.1107/S1600536807065099

organic compounds

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ISSN: 2056-9890

Volume 64| Part 1| January 2008| Page o274

https://doi.org/10.1107/S1600536807065099

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2-(9H-Fluoren-9-ylidenemethyl)thiophene

Lucia Perašínová,^a ^* Martin Štefko,^b Daniel Végh ^b and Jozef Kožíšek ^a

^aInstitute of Physical Chemistry and Chemical Physics, Slovak University of Technology, Radlinského 9, SK-812 37 Bratislava, Slovak Republic, and ^bInstitute of Organic Chemistry, Catalysis and Petrochemistry, Faculty of Chemical Technology, Slovak Technical University, Radlinskeho 9, Bratislava 81237, Slovak Republic
^*Correspondence e-mail: lucia.perasinova@stuba.sk

(Received 19 November 2007; accepted 2 December 2007; online 18 December 2007)

The title compound, C₁₈H₁₂S, contains a thiophene ring which is disordered by rotation of 180° about the linking C—C bond. The site occupancies of the major and minor components of the disordered ring are 0.900 (3) and 0.100 (3), respectively. In one of these disordered components, the molecule is stabilized by an intramolecular C—H⋯S hydrogen bond. The compound was synthesized in good yield (80%) by a modified phase-transfer-catalysed condensation of fluorene with thiophene-2-carbaldehyde.

Related literature

For a related structure, see: Fave et al., 2004 . For related literature, see: Allen (2002 ); Lukeš et al. (2003 ); Mullen & Wegner (1998 ).

Experimental

Crystal data

C₁₈H₁₂S
M_r = 260.34
Orthorhombic, F d d 2
a = 20.757 (4) Å
b = 44.434 (9) Å
c = 5.6260 (11) Å
V = 5189.0 (18) Å³
Z = 16
Mo Kα radiation
μ = 0.23 mm⁻¹
T = 100 (2) K
0.57 × 0.13 × 0.08 mm

Data collection

Oxford Diffraction Gemini R CCD diffractometer
Absorption correction: analytical (Clark & Reid, 1995 ) T_min = 0.938, T_max = 0.985
11725 measured reflections
3018 independent reflections
1903 reflections with I > 2σ(I)
R_int = 0.029

Refinement

R[F² > 2σ(F²)] = 0.035
wR(F²) = 0.090
S = 0.99
3018 reflections
180 parameters
4 restraints
H-atom parameters constrained
Δρ_max = 0.15 e Å⁻³
Δρ_min = −0.17 e Å⁻³
Absolute structure: Flack (1983 ), 1110 Friedel pairs
Flack parameter: −0.07 (8)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2A⋯S1A	0.95	2.55	3.311 (4)	139

Data collection: CrysAlis CCD (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ); cell refinement: CrysAlis CCD; data reduction: CrysAlis RED (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 1998 ); software used to prepare material for publication: enCIFer (Allen et al., 2004 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536807065099/fj2086sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536807065099/fj2086Isup2.hkl

checkCIF report

Comment top

Our synthetic efforts have been focused on a set of multi-ring monomer systems based on thiophene and fluorene ring system. In this respect, the relationship between the charge transport properties in OFET devices (Mullen & Wegner, 1998) and molecular properties such as redox reversibility and crystal structure have been investigated. As active layers, we used oligomers based on molecules consisting of alternating thiophene and fluorene moieties.

In the title compound (1) the S1—C15 and S1—C18 bond lengths of 1.725 (3) Å and 1.692 (3) Å are in a quite good agreement with similar thiophene compounds in the Cambridge Structural Database (CSD; Version 5.27, 2006 release; Allen, 2002); for example, 2,2',5,5'-tetrakis(2-Thienyl)-3,4:3',4'- bis(tetramethylene)-1,1'-biphosphole (Fave et. al., 2004; CDS refcode BERCIL). The thiophene ring is disordered by rotation about the inter-ring C—C bond. There is one intramolecular C–H···S hydrogen bond.

Related literature top

For a related structure, see: Fave et al., 2004.

For related literature, see: Allen (2002); Lukeš et al. (2003); Mullen & Wegner (1998).

Experimental top

8.3 g (0.05 mol) of fluorene and 5.6 g (0.05 mol) of thiophene-2-carbaldehyde were dissolved in 70 ml of toluene. Then 70 ml 40% NaOH and 2.9 g (0.009 mol) (n-Bu)₄N⁺Br^- were added. The resulting heterogenous mixture was vigorously stirred at room temperature for 12 h. After completion of the reaction (TLC control), the water layer was separated, and the organic layer was washed with 100 ml 10% HCl, 300 ml water, 300 ml of brine and dried over Na₂SO₄. After evaporation of the solvent under reduced pressure, a dark oil was obtained, which was further dissolved in boiling MeOH, decolorized with Norit, filtered and left to cool to room temperature to obtain 10.4 g (80%) of yellow needles m.p.: 75°C (lit. 73–75°C) (Lukeš et al., 2003). The crude product could be purified by column chromatography using silica gel Merck 60 in toluene as an eluent R_f = 0.71 (toluene).

¹H NMR (300 MHz, CDCl₃ p.p.m.): δ = 8.11 (d, J=7.79 Hz, 1 H), 7.68 – 7.74 (m, 3 H), 7.60 (s, 1 H), 7.42 – 7.45 (m, 2 H), 7.27 – 7.38 (m, 3 H), 7.12 – 7.23 (m, 2 H).

¹³C-NMR (75 MHz, CDCl₃, p.p.m.) δ = 141.19, 139.48, 139.06, 138.91, 136.51, 136.12, 129.25, 128.72, 128.22, 127.57, 127.32, 126.97, 126.82, 124.34, 120.14, 119.74, 119.58, 118.98.

Structure description top

For a related structure, see: Fave et al., 2004.

For related literature, see: Allen (2002); Lukeš et al. (2003); Mullen & Wegner (1998).

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis CCD (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 1998); software used to prepare material for publication: enCIFer (Allen et al., 2004).

Figures top

Fig. 1. The atomic numbering scheme of 2-(9H-fluoren-9-ylidenemethyl)thiophene. Only the major component of the disordered thiophene ring is shown. Displacement ellipsoids are drawn at the 30% probability level. Hydrogen-bond interactions are indicated by dashed lines.

2-(9H-Fluoren-9-ylidenemethyl)thiophene top

Crystal data top

C₁₈H₁₂S	F(000) = 2176
M_r = 260.34	D_x = 1.333 Mg m⁻³
Orthorhombic, Fdd2	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: F 2 -2d	Cell parameters from 4617 reflections
a = 20.757 (4) Å	θ = 3.7–29.1°
b = 44.434 (9) Å	µ = 0.23 mm⁻¹
c = 5.6260 (11) Å	T = 100 K
V = 5189.0 (18) Å³	Block, yellow
Z = 16	0.57 × 0.13 × 0.08 mm

Data collection top

Oxford Diffraction Gemini R CCD diffractometer	3018 independent reflections
Radiation source: fine-focus sealed tube	1903 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.029
Rotation method data acquisition using ω and φ scans	θ_max = 29.1°, θ_min = 3.8°
Absorption correction: analytical (Clark & Reid, 1995)	h = −27→25
T_min = 0.938, T_max = 0.985	k = −59→58
11725 measured reflections	l = −7→7

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)] = 0.035	H-atom parameters constrained
wR(F²) = 0.090	w = 1/[σ²(F_o²) + (0.0485P)²] where P = (F_o² + 2F_c²)/3
S = 0.99	(Δ/σ)_max < 0.001
3018 reflections	Δρ_max = 0.15 e Å⁻³
180 parameters	Δρ_min = −0.17 e Å⁻³
4 restraints	Absolute structure: Flack (1983), 1110 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.07 (8)

Crystal data top

C₁₈H₁₂S	V = 5189.0 (18) Å³
M_r = 260.34	Z = 16
Orthorhombic, Fdd2	Mo Kα radiation
a = 20.757 (4) Å	µ = 0.23 mm⁻¹
b = 44.434 (9) Å	T = 100 K
c = 5.6260 (11) Å	0.57 × 0.13 × 0.08 mm

Data collection top

Oxford Diffraction Gemini R CCD diffractometer	3018 independent reflections
Absorption correction: analytical (Clark & Reid, 1995)	1903 reflections with I > 2σ(I)
T_min = 0.938, T_max = 0.985	R_int = 0.029
11725 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.035	H-atom parameters constrained
wR(F²) = 0.090	Δρ_max = 0.15 e Å⁻³
S = 0.99	Δρ_min = −0.17 e Å⁻³
3018 reflections	Absolute structure: Flack (1983), 1110 Friedel pairs
180 parameters	Absolute structure parameter: −0.07 (8)
4 restraints

Special details top

Experimental. face-indexed (CrysAlis RED; Oxford Diffraction, 2006)

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	Occ. (<1)
C1	0.35040 (9)	0.03543 (4)	−0.1480 (3)	0.0504 (5)
C2	0.40287 (10)	0.01668 (4)	−0.1107 (4)	0.0605 (6)
H2A	0.4298	0.0194	0.0241	0.073*
C3	0.41552 (10)	−0.00616 (5)	−0.2727 (4)	0.0656 (6)
H3A	0.4516	−0.0189	−0.2475	0.079*
C4	0.37726 (11)	−0.01069 (5)	−0.4680 (4)	0.0640 (6)
H4A	0.3876	−0.0262	−0.5781	0.077*
C5	0.32362 (10)	0.00724 (4)	−0.5052 (4)	0.0594 (5)
H5A	0.2965	0.0040	−0.6387	0.071*
C6	0.31044 (9)	0.02985 (4)	−0.3442 (3)	0.0490 (5)
C7	0.25624 (9)	0.05093 (4)	−0.3394 (3)	0.0493 (5)
C8	0.20399 (10)	0.05396 (5)	−0.4884 (4)	0.0607 (5)
H8A	0.1994	0.0413	−0.6237	0.073*
C9	0.15827 (11)	0.07574 (5)	−0.4373 (4)	0.0670 (6)
H9A	0.1219	0.0780	−0.5380	0.080*
C10	0.16522 (10)	0.09415 (5)	−0.2405 (4)	0.0658 (6)
H10A	0.1334	0.1090	−0.2079	0.079*
C11	0.21746 (10)	0.09134 (5)	−0.0913 (4)	0.0608 (5)
H11A	0.2221	0.1043	0.0419	0.073*
C12	0.26339 (9)	0.06932 (4)	−0.1380 (3)	0.0490 (5)
C13	0.32372 (9)	0.06148 (4)	−0.0145 (3)	0.0490 (5)
C14	0.34399 (9)	0.07789 (4)	0.1761 (3)	0.0518 (5)
H14A	0.3125	0.0921	0.2256	0.062*
C15A	0.40114 (9)	0.07913 (4)	0.3214 (3)	0.0513 (5)	0.900 (3)
C18A	0.50774 (12)	0.07874 (5)	0.5125 (5)	0.0731 (7)	0.900 (3)
H18A	0.5513	0.0759	0.5592	0.088*	0.900 (3)
C17A	0.46607 (12)	0.09565 (5)	0.6332 (4)	0.0670 (6)	0.900 (3)
H17A	0.4767	0.1058	0.7767	0.080*	0.900 (3)
C16A	0.4056 (4)	0.0970 (4)	0.529 (3)	0.0747 (14)	0.900 (3)
H16A	0.3710	0.1087	0.5900	0.090*	0.900 (3)
S1A	0.47511 (8)	0.06280 (3)	0.26734 (16)	0.0755 (3)	0.900 (3)
C15B	0.40114 (9)	0.07913 (4)	0.3214 (3)	0.0513 (5)	0.100 (3)
C17B	0.46607 (12)	0.09565 (5)	0.6332 (4)	0.0670 (6)	0.100 (3)
H17B	0.4781	0.1058	0.7750	0.080*	0.100 (3)
C18B	0.50774 (12)	0.07874 (5)	0.5125 (5)	0.0731 (7)	0.100 (3)
H18B	0.5512	0.0758	0.5602	0.088*	0.100 (3)
C16B	0.481 (3)	0.0659 (10)	0.311 (4)	0.0755 (3)	0.100 (3)
H16B	0.5013	0.0532	0.1960	0.091*	0.100 (3)
S1B	0.3980 (11)	0.0978 (10)	0.532 (7)	0.0747 (14)	0.100 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0532 (11)	0.0451 (11)	0.0528 (11)	−0.0072 (9)	0.0047 (9)	−0.0017 (9)
C2	0.0557 (12)	0.0503 (12)	0.0754 (13)	−0.0021 (10)	−0.0032 (11)	−0.0117 (11)
C3	0.0575 (12)	0.0517 (12)	0.0874 (16)	0.0001 (10)	0.0055 (12)	−0.0126 (12)
C4	0.0699 (14)	0.0503 (13)	0.0717 (13)	−0.0051 (11)	0.0093 (13)	−0.0153 (12)
C5	0.0684 (13)	0.0544 (12)	0.0555 (11)	−0.0128 (10)	0.0014 (11)	−0.0072 (11)
C6	0.0570 (11)	0.0428 (11)	0.0473 (10)	−0.0082 (9)	0.0039 (10)	−0.0004 (9)
C7	0.0542 (11)	0.0438 (11)	0.0500 (11)	−0.0054 (9)	0.0035 (9)	0.0041 (10)
C8	0.0657 (13)	0.0608 (13)	0.0557 (10)	−0.0042 (11)	−0.0049 (12)	0.0017 (11)
C9	0.0649 (14)	0.0688 (15)	0.0673 (15)	−0.0031 (11)	−0.0130 (11)	0.0128 (12)
C10	0.0643 (13)	0.0580 (13)	0.0750 (14)	0.0076 (10)	−0.0009 (12)	0.0077 (13)
C11	0.0671 (13)	0.0519 (12)	0.0634 (12)	0.0033 (10)	0.0028 (12)	−0.0026 (11)
C12	0.0520 (11)	0.0468 (10)	0.0483 (11)	−0.0047 (9)	0.0057 (8)	0.0018 (9)
C13	0.0528 (10)	0.0461 (10)	0.0482 (11)	−0.0072 (9)	0.0042 (9)	0.0000 (9)
C14	0.0555 (11)	0.0487 (11)	0.0513 (11)	−0.0028 (9)	0.0087 (9)	−0.0005 (9)
C15A	0.0598 (12)	0.0461 (11)	0.0480 (11)	−0.0100 (9)	−0.0005 (9)	0.0023 (9)
C18A	0.0757 (15)	0.0666 (15)	0.0771 (14)	−0.0061 (12)	−0.0193 (14)	0.0019 (14)
C17A	0.0865 (16)	0.0614 (14)	0.0531 (12)	−0.0118 (13)	−0.0108 (12)	−0.0052 (12)
C16A	0.082 (3)	0.0744 (16)	0.0680 (12)	−0.022 (2)	−0.005 (2)	0.0022 (11)
S1A	0.0667 (6)	0.0868 (6)	0.0731 (5)	0.0098 (4)	−0.0143 (4)	−0.0252 (5)
C15B	0.0598 (12)	0.0461 (11)	0.0480 (11)	−0.0100 (9)	−0.0005 (9)	0.0023 (9)
C17B	0.0865 (16)	0.0614 (14)	0.0531 (12)	−0.0118 (13)	−0.0108 (12)	−0.0052 (12)
C18B	0.0757 (15)	0.0666 (15)	0.0771 (14)	−0.0061 (12)	−0.0193 (14)	0.0019 (14)
C16B	0.0667 (6)	0.0868 (6)	0.0731 (5)	0.0098 (4)	−0.0143 (4)	−0.0252 (5)
S1B	0.082 (3)	0.0744 (16)	0.0680 (12)	−0.022 (2)	−0.005 (2)	0.0022 (11)

Geometric parameters (Å, º) top

C1—C2	1.387 (3)	C10—C11	1.377 (3)
C1—C6	1.403 (3)	C10—H10A	0.9500
C1—C13	1.487 (3)	C11—C12	1.391 (3)
C2—C3	1.389 (3)	C11—H11A	0.9500
C2—H2A	0.9500	C12—C13	1.474 (3)
C3—C4	1.371 (3)	C13—C14	1.363 (3)
C3—H3A	0.9500	C14—C15A	1.442 (3)
C4—C5	1.385 (3)	C14—H14A	0.9500
C4—H4A	0.9500	C15A—C16A	1.416 (19)
C5—C6	1.380 (3)	C15A—S1A	1.725 (3)
C5—H5A	0.9500	C18A—C17A	1.332 (3)
C6—C7	1.464 (3)	C18A—S1A	1.692 (3)
C7—C8	1.377 (3)	C18A—H18A	0.9500
C7—C12	1.405 (3)	C17A—C16A	1.388 (3)
C8—C9	1.386 (3)	C17A—H17A	0.9500
C8—H8A	0.9500	C16A—H16A	0.9500
C9—C10	1.384 (3)	C16B—H16B	0.9500
C9—H9A	0.9500

C2—C1—C6	118.53 (18)	C11—C10—H10A	119.5
C2—C1—C13	133.10 (18)	C9—C10—H10A	119.5
C6—C1—C13	108.35 (17)	C10—C11—C12	119.2 (2)
C1—C2—C3	119.2 (2)	C10—C11—H11A	120.4
C1—C2—H2A	120.4	C12—C11—H11A	120.4
C3—C2—H2A	120.4	C11—C12—C7	119.26 (19)
C4—C3—C2	121.6 (2)	C11—C12—C13	131.25 (18)
C4—C3—H3A	119.2	C7—C12—C13	109.45 (17)
C2—C3—H3A	119.2	C14—C13—C12	120.45 (17)
C3—C4—C5	120.2 (2)	C14—C13—C1	134.33 (19)
C3—C4—H4A	119.9	C12—C13—C1	105.19 (16)
C5—C4—H4A	119.9	C13—C14—C15A	136.09 (18)
C6—C5—C4	118.6 (2)	C13—C14—H14A	112.0
C6—C5—H5A	120.7	C15A—C14—H14A	112.0
C4—C5—H5A	120.7	C16A—C15A—C14	122.8 (4)
C5—C6—C1	121.84 (18)	C16A—C15A—S1A	108.9 (4)
C5—C6—C7	129.06 (17)	C14—C15A—S1A	128.03 (14)
C1—C6—C7	109.09 (16)	C17A—C18A—S1A	113.1 (2)
C8—C7—C12	121.16 (18)	C17A—C18A—H18A	123.5
C8—C7—C6	131.03 (19)	S1A—C18A—H18A	123.5
C12—C7—C6	107.78 (17)	C18A—C17A—C16A	113.4 (9)
C7—C8—C9	118.8 (2)	C18A—C17A—H17A	123.3
C7—C8—H8A	120.6	C16A—C17A—H17A	123.3
C9—C8—H8A	120.6	C17A—C16A—C15A	112.5 (12)
C10—C9—C8	120.5 (2)	C17A—C16A—H16A	123.8
C10—C9—H9A	119.8	C15A—C16A—H16A	123.8
C8—C9—H9A	119.8	C18A—S1A—C15A	92.08 (13)
C11—C10—C9	121.1 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2A···S1A	0.95	2.55	3.311 (4)	139

Experimental details

Crystal data
Chemical formula	C₁₈H₁₂S
M_r	260.34
Crystal system, space group	Orthorhombic, Fdd2
Temperature (K)	100
a, b, c (Å)	20.757 (4), 44.434 (9), 5.6260 (11)
V (Å³)	5189.0 (18)
Z	16
Radiation type	Mo Kα
µ (mm⁻¹)	0.23
Crystal size (mm)	0.57 × 0.13 × 0.08

Data collection
Diffractometer	Oxford Diffraction Gemini R CCD
Absorption correction	Analytical (Clark & Reid, 1995)
T_min, T_max	0.938, 0.985
No. of measured, independent and observed [I > 2σ(I)] reflections	11725, 3018, 1903
R_int	0.029
(sin θ/λ)_max (Å⁻¹)	0.683

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.035, 0.090, 0.99
No. of reflections	3018
No. of parameters	180
No. of restraints	4
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.15, −0.17
Absolute structure	Flack (1983), 1110 Friedel pairs
Absolute structure parameter	−0.07 (8)

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), DIAMOND (Brandenburg, 1998), enCIFer (Allen et al., 2004).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2A···S1A	0.95	2.55	3.311 (4)	138.51

Acknowledgements

The authors thank the Grant Agency of Slovak Republic (grant Nos. 1/2449/05, 1/4453/07 and APVT-20–007304) as well as the Structural Funds, Interreg IIIA, for financial support in purchasing the diffractometer.

References

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