organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

1-{5-[2-Chloro-5-(tri­fluoro­meth­yl)phen­yl]thio­phen-2-yl}ethanone

aDepartment of Organic Chemistry, Ivan Franko National University of Lviv, Kyryla and Mefodiya 6, Lviv 79005, Ukraine, and bFaculty of Chemistry, University of Wrocław, 14 Joliot-Curie St, 50-383 Wrocław, Poland
*Correspondence e-mail: horrak@gmail.com

(Received 11 January 2011; accepted 31 January 2011; online 9 February 2011)

In the title molecule, C13H8ClF3OS, the dihedral angle between the mean planes of 2-chloro-5-(trifluoro­meth­yl)phenyl and tiophene rings is 54.37 (5)°. The acethyl group is twisted by 8.1 (2)° with respect to the thio­phene ring. The CF3 group is disordered over two sets of sites with occupations of 0.49 (3) and 0.51 (3). The crystal packing features C—H⋯F and C—H⋯O hydrogen bonds, forming dimers which are connected into chains along the c axis by C—H⋯O hydrogen bonds and C—Cl⋯π [Cl⋯π = 3.415 (1) Å and C—Cl⋯π = 151.56 (5)°] inter­actions. The chains are further connected into layers perpendicular to the a axis by C—H⋯O inter­actions.

Related literature

For the general synthetic procedure, see: Matiychuk et al. (2010[Matiychuk, V. S., Obushak, N. D., Lytvyn, R. Z. & Horak, Yu. I. (2010). Chem. Heterocycl. Compd, 46, 50-55.]). For the biologial activity of aryl­thio­phenes, see: Reddy et al. (2005[Reddy, T. J., Leclair, M. & Proulx, M. (2005). Synlett, 4, 583-586.]); Anderson et al. (1963[Anderson, E. L., Casey, J. E., Emas, M., Force, E. E., Jensen, E. M., Matz, R. S. & Rivard, D. E. (1963). J. Med. Chem. 6, 787-791.]); Bohlmann et al. (1984[Bohlmann, F., Knauf, W. & Misra, L. N. (1984). Tetrahedron, 40, 4987-4989.]); Michaelides et al. (1997[Michaelides, M. R., Hong, Yu., DiDomenico, S., Bayburt, E. K., Asin, K. E., Britton, D. R., Wel Lin, Ch. & Shiosaki, K. (1997). J. Med. Chem. 40, 1585-1599.]); Tanaka et al. (1998[Tanaka, A., Terasawa, T., Hagihara, H., Sakumi, Yu., Ishibe, N., Sawada, M., Takasugi, H. & Tanaka, H. (1998). J. Med. Chem. 41, 2390-2410.]) and for their applications, see Masui et al. (2004[Masui, K., Mori, A., Okano, K., Takamura, K., Kinoshita, M. & Ikeda, T. (2004). Org. Lett. 6, 2011-2014.]); Roncali (1992[Roncali, J. (1992). Chem. Rev. 92, 711-738.], 1997[Roncali, J. (1997). Chem. Rev. 97, 173-205.]). For methods of obtaining aryl­thio­phenes via cross-coupling reactions, see: Stanforth (1998[Stanforth, S. P. (1998). Tetrahedron, 54, 263-303.]).

[Scheme 1]

Experimental

Crystal data
  • C13H8ClF3OS

  • Mr = 304.70

  • Monoclinic, P 21 /c

  • a = 15.330 (6) Å

  • b = 10.809 (4) Å

  • c = 7.676 (3) Å

  • β = 93.72 (3)°

  • V = 1269.3 (8) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.49 mm−1

  • T = 100 K

  • 0.20 × 0.15 × 0.08 mm

Data collection
  • Kuma KM-4-CCD diffractometer

  • Absorption correction: analytical (CrysAlis RED; Oxford Diffraction, 2006[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Wrocław, Poland.]) Tmin = 0.86, Tmax = 0.93

  • 16021 measured reflections

  • 4377 independent reflections

  • 3093 reflections with I > 2σ(I)

  • Rint = 0.034

Refinement
  • R[F2 > 2σ(F2)] = 0.039

  • wR(F2) = 0.097

  • S = 1.00

  • 4377 reflections

  • 201 parameters

  • H-atom parameters constrained

  • Δρmax = 0.49 e Å−3

  • Δρmin = −0.25 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C22—H22C⋯F1Ai 0.98 2.55 3.520 (13) 168
C22—H22B⋯O1ii 0.98 2.62 3.526 (2) 154
C22—H22A⋯O1iii 0.98 2.67 3.562 (3) 152
C56—H56⋯O1i 0.95 2.78 3.697 (2) 162
Symmetry codes: (i) -x+1, -y+1, -z+2; (ii) [-x+1, y-{\script{1\over 2}}, -z+{\script{5\over 2}}]; (iii) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}].

Data collection: CrysAlis CCD (Oxford Diffraction, 2006[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Wrocław, Poland.]); cell refinement: CrysAlis RED (Oxford Diffraction, 2006[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Wrocław, Poland.]); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: DIAMOND (Brandenburg, 2006)[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]; software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

Arylthiophenes and their homologues are an important class of organic compounds. The arylthiophenes units are represented in several types of compounds of current interest including polymers (Roncali, 1992; Roncali, 1997), liquid crystals (Masui et al., 2004), ligands and molecules of medicinal interest (Michaelides et al., 1997; Tanaka et al., 1998; Reddy et al., 2005; Anderson et al., 1963). In view of the arylthiophenes importance a number of catalytic methods of these compounds formation from precursors in a cross-coupling reactions have been developed over the last two decades (Stanforth, 1998). However, these methods proceed in two steps via an organometallic intermediate and their stability is often limited.

The molecule of the title compound is not plannar (see Fig. 1). The dihedral angle between the mean planes of 2-chloro-5-(trifluoromethyl)phenyl and tiophene rings is equal to 54.37 (5)°. The acethyl group is twisted with respect to the tiophene ring by 8.1 (2)°. The CF3 group is disordered with almoust equal occupations of two positions, which are realised by the rotation around C1–C55 bond. The crystal structure packing is governed by the hydrogen bonds of C–H···F and C–H···O types and C–Cl···π interactions. The centrosymmetric dimers are formed by the pairs of C22–H22C···F1Ai and C56–H56···O1i hydrogen bonds. The dimers are connected into the chains that propagate along z axis direction by means of C22–H22A···O1iii hydrogen bonds and C52–Cl1···Cgiv interactions (symmetry code: (iv) x, 1/2 - y, z + 1/2). The geometrical parameters of C52–Cl1···Cgiv interaction are as follows: Cl1···Cgiv distance is equal to 3.415 (1) Å and the C52–Cl1···Cgiv angle 151.56 (5)°. The vast layers perpendicular to x axis direction are formed of above mentioned chains connected with each other by C22–H22B···O1ii hydrogen bonds (see Fig. 2).

Related literature top

For the general synthetic procedure, see: Matiychuk et al. (2010). For the biologial activity of arylthiophenes, see: Reddy et al. (2005); Anderson et al. (1963); Bohlmann et al. (1984); Michaelides et al. (1997); Tanaka et al. (1998) and for their applications, see Masui et al. (2004); Roncali (1992, 1997). For methods of obtaining arylthiophenes via cross-coupling reactions, see: Stanforth (1998).

Experimental top

Water solution of 7 g of NaNO2 (25 ml) was added dropwise to a cooled stirred mixture of 2-chloro-5-trifluoromethylaniline (19.5 g, 0.1 mol, Fluka) and 60 ml of 20% HCl. After completion of reaction the solution was filtered and added dropwise to well stirred mixture of 2-acetylthiophene (12.6 g, 0.1 mol, Fluka), acetone (40 ml) and CuCl2.2H2O (1.5 g, 8.7 mmol) during 20 min. After 3 h the reaction mixture was diluted with 250 ml of water and 50 ml of CHCl3, organic layer was separated and dried over Na2SO4, and concentrated under reduced pressure. Residue was distilled at 400 Pa (453–458 K) and gave 11.6 g (38% yield) of 1-{5-[2-chloro-5-(trifluoromethyl)phenyl]-2-thienyl}ethanone. Yellow crystals suitable for X-ray analysis were obtained by recrystallization from n-hexane.

Refinement top

All H atoms were found in difference-Fourier maps. In the final refinement cycles, all H atoms were positioned geometrically and treated as riding atoms, with C–H distance of 0.95 Å and with Uiso(H) values of 1.2Ueq(C).

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. Asymmetric unit of the crystal alnog with atom labeling scheme. The thermal ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. The packing of the title compound along with intermolecular hydrogen bonds.
1-{5-[2-Chloro-5-(trifluoromethyl)phenyl]thiophen-2-yl}ethanone top
Crystal data top
C13H8ClF3OSF(000) = 616
Mr = 304.70Dx = 1.594 Mg m3
Monoclinic, P21/cMelting point: 347 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 15.330 (6) ÅCell parameters from 11592 reflections
b = 10.809 (4) Åθ = 2.3–33.9°
c = 7.676 (3) ŵ = 0.49 mm1
β = 93.72 (3)°T = 100 K
V = 1269.3 (8) Å3Block, colourless
Z = 40.20 × 0.15 × 0.08 mm
Data collection top
Kuma KM-4-CCD
diffractometer
4377 independent reflections
Radiation source: fine-focus sealed tube3093 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.034
ω scansθmax = 33.8°, θmin = 3.3°
Absorption correction: analytical
(CrysAlis RED; Oxford Diffraction, 2006)
h = 1923
Tmin = 0.86, Tmax = 0.93k = 1216
16021 measured reflectionsl = 119
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)] = 0.039Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.097H-atom parameters constrained
S = 1.00 w = 1/[σ2(Fo2) + (0.054P)2]
where P = (Fo2 + 2Fc2)/3
4377 reflections(Δ/σ)max = 0.001
201 parametersΔρmax = 0.49 e Å3
0 restraintsΔρmin = 0.25 e Å3
Crystal data top
C13H8ClF3OSV = 1269.3 (8) Å3
Mr = 304.70Z = 4
Monoclinic, P21/cMo Kα radiation
a = 15.330 (6) ŵ = 0.49 mm1
b = 10.809 (4) ÅT = 100 K
c = 7.676 (3) Å0.20 × 0.15 × 0.08 mm
β = 93.72 (3)°
Data collection top
Kuma KM-4-CCD
diffractometer
4377 independent reflections
Absorption correction: analytical
(CrysAlis RED; Oxford Diffraction, 2006)
3093 reflections with I > 2σ(I)
Tmin = 0.86, Tmax = 0.93Rint = 0.034
16021 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0390 restraints
wR(F2) = 0.097H-atom parameters constrained
S = 1.00Δρmax = 0.49 e Å3
4377 reflectionsΔρmin = 0.25 e Å3
201 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*/UeqOcc. (<1)
Cl10.09807 (2)0.28619 (3)1.05277 (5)0.02440 (10)
S10.37102 (2)0.42596 (3)1.04508 (5)0.01971 (9)
O10.54239 (7)0.39388 (9)1.24469 (14)0.0261 (2)
C20.42729 (9)0.29067 (12)1.08963 (19)0.0181 (3)
C210.51398 (9)0.29623 (12)1.18365 (19)0.0208 (3)
C220.56531 (10)0.17781 (14)1.1983 (2)0.0276 (3)
H22A0.58120.15211.08210.041*
H22B0.52970.11331.24850.041*
H22C0.61850.19091.27380.041*
C30.37969 (9)0.18899 (12)1.02942 (19)0.0194 (3)
H30.40000.10621.04130.023*
C40.29753 (9)0.22147 (12)0.94833 (19)0.0192 (3)
H40.25620.16300.90100.023*
C50.28396 (9)0.34750 (11)0.94559 (18)0.0160 (3)
C510.20972 (9)0.41760 (11)0.86157 (18)0.0164 (3)
C520.12277 (9)0.39514 (12)0.89694 (18)0.0179 (3)
C530.05343 (9)0.45875 (12)0.81028 (19)0.0192 (3)
H530.00510.44130.83570.023*
C540.07070 (9)0.54733 (12)0.68726 (19)0.0198 (3)
H540.02410.59070.62700.024*
C550.15699 (9)0.57247 (12)0.65236 (18)0.0192 (3)
C10.17567 (10)0.66394 (15)0.5124 (2)0.0289 (4)
F10.2540 (6)0.7124 (13)0.528 (2)0.049 (3)0.49 (3)
F20.1209 (7)0.7645 (7)0.5195 (13)0.0485 (17)0.49 (3)
F30.1634 (9)0.6244 (10)0.3552 (8)0.059 (2)0.49 (3)
F1A0.2471 (7)0.7292 (12)0.549 (2)0.052 (2)0.51 (3)
F2A0.1125 (5)0.7352 (16)0.465 (2)0.070 (3)0.51 (3)
F3A0.1942 (11)0.5975 (8)0.3643 (11)0.079 (2)0.51 (3)
C560.22588 (9)0.50955 (12)0.73913 (18)0.0189 (3)
H560.28430.52900.71530.023*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.01931 (18)0.02759 (17)0.0267 (2)0.00030 (13)0.00436 (14)0.00743 (14)
S10.01739 (17)0.01659 (14)0.0246 (2)0.00050 (12)0.00288 (13)0.00172 (13)
O10.0217 (5)0.0253 (5)0.0307 (6)0.0040 (4)0.0041 (5)0.0034 (4)
C20.0151 (6)0.0200 (6)0.0193 (7)0.0012 (5)0.0017 (5)0.0023 (5)
C210.0178 (7)0.0234 (6)0.0214 (8)0.0002 (5)0.0024 (6)0.0072 (5)
C220.0194 (7)0.0266 (7)0.0362 (10)0.0026 (6)0.0034 (7)0.0065 (6)
C30.0184 (7)0.0194 (6)0.0208 (7)0.0027 (5)0.0033 (6)0.0005 (5)
C40.0201 (7)0.0185 (6)0.0189 (7)0.0012 (5)0.0009 (6)0.0014 (5)
C50.0154 (6)0.0177 (5)0.0149 (7)0.0002 (5)0.0009 (5)0.0005 (5)
C510.0164 (6)0.0170 (5)0.0158 (7)0.0011 (5)0.0002 (5)0.0031 (5)
C520.0185 (7)0.0190 (5)0.0163 (7)0.0000 (5)0.0009 (5)0.0009 (5)
C530.0138 (6)0.0234 (6)0.0203 (7)0.0012 (5)0.0007 (5)0.0041 (5)
C540.0182 (7)0.0217 (6)0.0190 (7)0.0028 (5)0.0027 (6)0.0021 (5)
C550.0200 (7)0.0200 (6)0.0174 (7)0.0005 (5)0.0005 (5)0.0003 (5)
C10.0219 (8)0.0343 (8)0.0300 (9)0.0007 (6)0.0013 (7)0.0102 (7)
F10.015 (2)0.068 (5)0.062 (5)0.000 (3)0.003 (2)0.043 (4)
F20.050 (3)0.038 (2)0.059 (4)0.0255 (18)0.020 (2)0.0291 (19)
F30.115 (6)0.043 (3)0.0173 (15)0.024 (3)0.005 (2)0.0037 (17)
F1A0.053 (5)0.049 (3)0.053 (3)0.029 (3)0.008 (3)0.022 (2)
F2A0.0206 (16)0.093 (6)0.099 (7)0.016 (3)0.010 (3)0.074 (5)
F3A0.160 (6)0.051 (2)0.029 (2)0.010 (4)0.037 (3)0.0148 (18)
C560.0169 (7)0.0211 (6)0.0189 (7)0.0004 (5)0.0018 (5)0.0017 (5)
Geometric parameters (Å, º) top
Cl1—C521.738 (2)C51—C561.401 (2)
S1—C51.718 (2)C52—C531.398 (2)
S1—C21.721 (2)C53—C541.382 (2)
O1—C211.224 (2)C53—H530.9500
C2—C31.382 (2)C54—C551.393 (2)
C2—C211.472 (2)C54—H540.9500
C21—C221.503 (2)C55—C561.389 (2)
C22—H22A0.9800C55—C11.501 (2)
C22—H22B0.9800C1—F2A1.272 (8)
C22—H22C0.9800C1—F31.282 (8)
C3—C41.413 (2)C1—F11.309 (10)
C3—H30.9500C1—F1A1.317 (11)
C4—C51.378 (2)C1—F21.377 (7)
C4—H40.9500C1—F3A1.389 (8)
C5—C511.480 (2)C56—H560.9500
C51—C521.399 (2)
C5—S1—C291.94 (7)C53—C52—Cl1117.91 (11)
C3—C2—C21129.54 (12)C51—C52—Cl1120.28 (11)
C3—C2—S1111.25 (11)C54—C53—C52119.50 (13)
C21—C2—S1119.20 (10)C54—C53—H53120.3
O1—C21—C2120.70 (13)C52—C53—H53120.3
O1—C21—C22122.31 (14)C53—C54—C55119.52 (13)
C2—C21—C22116.98 (12)C53—C54—H54120.2
C21—C22—H22A109.5C55—C54—H54120.2
C21—C22—H22B109.5C56—C55—C54120.92 (13)
H22A—C22—H22B109.5C56—C55—C1119.42 (13)
C21—C22—H22C109.5C54—C55—C1119.58 (13)
H22A—C22—H22C109.5F3—C1—F1107.4 (8)
H22B—C22—H22C109.5F2A—C1—F1A110.1 (7)
C2—C3—C4112.70 (12)F3—C1—F2104.4 (6)
C2—C3—H3123.7F1—C1—F2103.8 (7)
C4—C3—H3123.7F2A—C1—F3A105.6 (6)
C5—C4—C3112.45 (12)F1A—C1—F3A103.8 (8)
C5—C4—H4123.8F2A—C1—C55115.3 (4)
C3—C4—H4123.8F3—C1—C55115.5 (4)
C4—C5—C51128.60 (12)F1—C1—C55114.4 (6)
C4—C5—S1111.66 (10)F1A—C1—C55113.4 (6)
C51—C5—S1119.62 (10)F2—C1—C55110.3 (4)
C52—C51—C56117.75 (12)F3A—C1—C55107.7 (4)
C52—C51—C5122.83 (12)C55—C56—C51120.46 (13)
C56—C51—C5119.41 (12)C55—C56—H56119.8
C53—C52—C51121.81 (13)C51—C56—H56119.8
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C22—H22C···F1Ai0.982.553.520 (13)168
C22—H22B···O1ii0.982.623.526 (2)154
C22—H22A···O1iii0.982.673.562 (3)152
C56—H56···O1i0.952.783.697 (2)162
Symmetry codes: (i) x+1, y+1, z+2; (ii) x+1, y1/2, z+5/2; (iii) x, y+1/2, z1/2.

Experimental details

Crystal data
Chemical formulaC13H8ClF3OS
Mr304.70
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)15.330 (6), 10.809 (4), 7.676 (3)
β (°) 93.72 (3)
V3)1269.3 (8)
Z4
Radiation typeMo Kα
µ (mm1)0.49
Crystal size (mm)0.20 × 0.15 × 0.08
Data collection
DiffractometerKuma KM-4-CCD
diffractometer
Absorption correctionAnalytical
(CrysAlis RED; Oxford Diffraction, 2006)
Tmin, Tmax0.86, 0.93
No. of measured, independent and
observed [I > 2σ(I)] reflections
16021, 4377, 3093
Rint0.034
(sin θ/λ)max1)0.782
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.039, 0.097, 1.00
No. of reflections4377
No. of parameters201
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.49, 0.25

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 2006), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C22—H22C···F1Ai0.982.553.520 (13)168
C22—H22B···O1ii0.982.623.526 (2)154
C22—H22A···O1iii0.982.673.562 (3)152
C56—H56···O1i0.952.783.697 (2)162
Symmetry codes: (i) x+1, y+1, z+2; (ii) x+1, y1/2, z+5/2; (iii) x, y+1/2, z1/2.
 

Acknowledgements

The authors acknowledge Professor T. Lis (University of Wroclaw) for providing the X-ray data collection faciltities.

References

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