organic compounds
of 4′-bromo-2,3,5,6-tetrafluorobiphenyl-4-carbonitrile
aInstitut für Organische Chemie, TU Bergakademie Freiberg, Leipziger Strasse 29, D-09596 Freiberg/Sachsen, Germany, and bDepartment of Chemistry and Biochemistry, University of Berne, Freiestrasse 3, CH-3012 Berne, Switzerland
*Correspondence e-mail: anke.schwarzer@chemie.tu-freiberg.de
The title compound, C13H4BrF4N, synthesized from 1,4′-bromoiodobenzene and 4-bromo-2,3,5,6-tetrafluorobenzonitrile in a coupling reaction was found to crystallize in the orthorhombic P212121. The two phenyl rings are rotated with respect to each other by 40.6 (6)°. The molecules interact via aryl–perfluoroaryl stacking [3.796 (2) and 3.773 (2) Å], resulting in intermolecular chains along the a-axis direction. C—H⋯F contacts of about 2.45 Å connect these chains. In contrast to the structure of the parent compound 4′-bromobiphenyl-4-carbonitrile, CN⋯Br contacts that could have given rise to a linear arrangement of the biphenyl molecules desirable for non-linear optical (NLO) materials are not observed in the packing. Instead, several Br⋯F [3.2405 (17) and 3.2777 (18) Å] and F⋯F [2.894 (2) Å] contacts of side-on type II form an intermolecular network of zigzag chains. The crystal studied was refined as an inversion twin.
Keywords: crystal structure; biphenyl; tetrafluoro substitution; bromo–cyano substitution; π–πF stacking; halogen interactions.
CCDC reference: 1060721
1. Related literature
For crystal structures of 4-cyano-4′-halogene substituted biphenyls, see: Gleason et al. (1991) for fluorine, Kronebusch et al. (1976) for bromine, Britton & Gleason (1991) for iodine. For halogen interactions in molecular crystal structures, see: Ramasubbu et al. (1986), Awwadi et al. (2006), Brammer et al. (2001) and Metrangolo et al. (2008). For interactions of halogens with cyano groups, see: Desiraju & Harlow (1989), Süss et al. (2005) and Mukherjee et al. (2014). For fluorine involved into these interactions, see: Schwarzer et al. (2010), Merz & Vasylyeva (2010), Schwarzer & Weber (2008) and Reichenbächer et al. (2005).
2. Experimental
2.1. Crystal data
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2.2. Data collection
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2.3. Refinement
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Data collection: SMART (Bruker, 2007); cell SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXL2012 (Sheldrick, 2015); molecular graphics: XP (Sheldrick, 2008); software used to prepare material for publication: WinGX (Farrugia, 2012), publCIF (Westrip, 2010) and SHELXLE (Hübschle et al., 2011).
Supporting information
CCDC reference: 1060721
https://doi.org/10.1107/S2056989015007847/im2464sup1.cif
contains datablocks I, Global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015007847/im2464Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989015007847/im2464Isup3.cml
Under inert conditions, 1-bromo-4-iodobenzene (22.6 g, 80 mmol) in THF (90 mL) was added dropwise to magnesium shaving (1.8 g, 75 mmol. The reaction mixture was refluxed for 90 min. After cooling to room temperature, CuBr (25.8 g, 180 mmol) was added and the mixture was stirred for 1 h at this temperature. Then 15 ml of 1,4-dioxane was added and the mixture was stirred for an hour followed by dropwise addition of a solution of 4-bromo-2,3,5,6-tetrafluorobenzonitrile (6.4 g, 25 mmol) in toluene (50 ml). After refluxing for 2 d, the mixture was cooled to room temperature, filtered over Celite and freed from solvents removed under reduced pressure. The residue was dissolved in toluene and washed with 3M HCl followed by aqueous NaOH solution. The organic phases were collected, dried over Na2SO4 and evaporated. The raw product was purified by δH = 7.57 (d, 3JHH = 8.9, 2H, H-9, H-13), 7.82 (d, 3JHH = 8.9, 2H, H-10, H12) ppm. 13C NMR (100 MHz; acetone-d6): δC = 94.30 (d, 2JCF = 17.4, C-2), 108.62 (t, 3JCF = -3.7, C-1), 125.52, 126.32 (s, C-8, C11), 127.04 (t, 2JCF = 17.4, C-5), 133.05 (t, 4JCF = 2.5, C-9), 133.32 (s, C-10), 143.39, 146.69 (d, 1JCF = -147.2, C-4), 147.01, 150.43 (d, 1JCF = -265.5, C-3) ppm. 19F NMR(376 MHz; acetone-d6): δF = -136.15 (F-1, d, 3JFF = 9.3 ), -142.53 (F-2, d, 3JFF = 9.3) ppm. GC—MS (m/z) 329 [M]+, 250 [M—Br]+, 231 [-F]+, 200 [-CF]+, 125, 99, 74, 50.
(SiO2; CH2Cl2/n-hexane, 2/1 v/v to yield 1.00 g (12 %) of the title compound. Single crystals suitable for X-ray diffraction were obtained from acetone solution at room temperature. Data for (I): M.p. 133-134 °C. 1H NMR(400 MHz; acetone-d6):For crystal structures of 4-cyano-4'-halogene substituted biphenyls, see: Gleason et al. (1991) for fluorine, Kronebusch et al. (1976) for bromine, Britton & Gleason (1991) for iodine. For halogen interactions in molecular crystal structures, see: Ramasubbu et al. (1986), Awwadi et al. (2006), Brammer et al. (2001) and Metrangolo et al. (2008). For interactions of halogens with cyano groups, see: Desiraju & Harlow (1989), Süss et al. (2005) and Mukherjee et al. (2014). For fluorine involved into these interactions, see: Schwarzer et al. (2010), Merz & Vasylyeva (2010), Schwarzer & Weber (2008) and Reichenbächer et al. (2005).
Under inert conditions, 1-bromo-4-iodobenzene (22.6 g, 80 mmol) in THF (90 mL) was added dropwise to magnesium shaving (1.8 g, 75 mmol. The reaction mixture was refluxed for 90 min. After cooling to room temperature, CuBr (25.8 g, 180 mmol) was added and the mixture was stirred for 1 h at this temperature. Then 15 ml of 1,4-dioxane was added and the mixture was stirred for an hour followed by dropwise addition of a solution of 4-bromo-2,3,5,6-tetrafluorobenzonitrile (6.4 g, 25 mmol) in toluene (50 ml). After refluxing for 2 d, the mixture was cooled to room temperature, filtered over Celite and freed from solvents removed under reduced pressure. The residue was dissolved in toluene and washed with 3M HCl followed by aqueous NaOH solution. The organic phases were collected, dried over Na2SO4 and evaporated. The raw product was purified by δH = 7.57 (d, 3JHH = 8.9, 2H, H-9, H-13), 7.82 (d, 3JHH = 8.9, 2H, H-10, H12) ppm. 13C NMR (100 MHz; acetone-d6): δC = 94.30 (d, 2JCF = 17.4, C-2), 108.62 (t, 3JCF = -3.7, C-1), 125.52, 126.32 (s, C-8, C11), 127.04 (t, 2JCF = 17.4, C-5), 133.05 (t, 4JCF = 2.5, C-9), 133.32 (s, C-10), 143.39, 146.69 (d, 1JCF = -147.2, C-4), 147.01, 150.43 (d, 1JCF = -265.5, C-3) ppm. 19F NMR(376 MHz; acetone-d6): δF = -136.15 (F-1, d, 3JFF = 9.3 ), -142.53 (F-2, d, 3JFF = 9.3) ppm. GC—MS (m/z) 329 [M]+, 250 [M—Br]+, 231 [-F]+, 200 [-CF]+, 125, 99, 74, 50.
(SiO2; CH2Cl2/n-hexane, 2/1 v/v to yield 1.00 g (12 %) of the title compound. Single crystals suitable for X-ray diffraction were obtained from acetone solution at room temperature. Data for (I): M.p. 133-134 °C. 1H NMR(400 MHz; acetone-d6): detailsThe C-bound H atoms were positioned geometrically and allowed to ride on their parent atoms: C–H = 0.95 Å for aryl H atoms, with [Uiso(H) = 1.2Ueq(C)].
Data collection: SMART (Bruker, 2007); cell
SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXL2012 (Sheldrick, 2015); molecular graphics: XP (Sheldrick, 2008); software used to prepare material for publication: WinGX (Farrugia, 2012), publCIF (Westrip, 2010) and SHELXLE (Hübschle et al., 2011).C13H4BrF4N | Dx = 1.935 Mg m−3 |
Mr = 330.08 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, P212121 | Cell parameters from 4750 reflections |
a = 7.3560 (15) Å | θ = 3.2–28.4° |
b = 12.107 (2) Å | µ = 3.66 mm−1 |
c = 12.723 (3) Å | T = 93 K |
V = 1133.1 (4) Å3 | Splitter, colorless |
Z = 4 | 0.49 × 0.13 × 0.10 mm |
F(000) = 640 |
Bruker SMART CCD area-detector diffractometer | 2930 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.053 |
phi and ω scans | θmax = 29.8°, θmin = 2.3° |
Absorption correction: multi-scan (SADABS; Bruker, 2012) | h = −10→10 |
Tmin = 0.486, Tmax = 0.718 | k = −16→16 |
18347 measured reflections | l = −17→17 |
3234 independent reflections |
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.028 | w = 1/[σ2(Fo2) + (0.0144P)2] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.052 | (Δ/σ)max = 0.001 |
S = 0.99 | Δρmax = 0.46 e Å−3 |
3234 reflections | Δρmin = −0.31 e Å−3 |
173 parameters | Absolute structure: Refined as an inversion twin. |
0 restraints | Absolute structure parameter: 0.011 (9) |
C13H4BrF4N | V = 1133.1 (4) Å3 |
Mr = 330.08 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 7.3560 (15) Å | µ = 3.66 mm−1 |
b = 12.107 (2) Å | T = 93 K |
c = 12.723 (3) Å | 0.49 × 0.13 × 0.10 mm |
Bruker SMART CCD area-detector diffractometer | 3234 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2012) | 2930 reflections with I > 2σ(I) |
Tmin = 0.486, Tmax = 0.718 | Rint = 0.053 |
18347 measured reflections |
R[F2 > 2σ(F2)] = 0.028 | H-atom parameters constrained |
wR(F2) = 0.052 | Δρmax = 0.46 e Å−3 |
S = 0.99 | Δρmin = −0.31 e Å−3 |
3234 reflections | Absolute structure: Refined as an inversion twin. |
173 parameters | Absolute structure parameter: 0.011 (9) |
0 restraints |
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. Refined as a 2-component inversion twin. |
x | y | z | Uiso*/Ueq | ||
Br1 | 0.89811 (4) | 0.35795 (3) | 0.37922 (2) | 0.01853 (8) | |
F1 | 0.7744 (2) | 1.00596 (16) | 0.75920 (12) | 0.0196 (4) | |
F2 | 0.7639 (2) | 0.79698 (15) | 0.69387 (12) | 0.0179 (4) | |
F3 | 1.0359 (2) | 0.90632 (14) | 0.37137 (13) | 0.0163 (4) | |
F4 | 1.0323 (2) | 1.11450 (14) | 0.43493 (13) | 0.0196 (4) | |
N1 | 0.9005 (4) | 1.2681 (2) | 0.66563 (19) | 0.0208 (6) | |
C1 | 0.9026 (4) | 1.1790 (2) | 0.6343 (2) | 0.0161 (6) | |
C2 | 0.9029 (5) | 1.0664 (2) | 0.5984 (2) | 0.0153 (6) | |
C3 | 0.8371 (4) | 0.9812 (3) | 0.6627 (2) | 0.0154 (7) | |
C4 | 0.8354 (4) | 0.8729 (3) | 0.6295 (2) | 0.0147 (6) | |
C5 | 0.9004 (4) | 0.8418 (2) | 0.5296 (2) | 0.0131 (6) | |
C6 | 0.9650 (4) | 0.9283 (3) | 0.4667 (2) | 0.0129 (6) | |
C7 | 0.9665 (4) | 1.0369 (3) | 0.4992 (2) | 0.0144 (6) | |
C8 | 0.8998 (5) | 0.7249 (2) | 0.4938 (2) | 0.0133 (6) | |
C9 | 0.9476 (4) | 0.6389 (3) | 0.5620 (2) | 0.0145 (6) | |
H9 | 0.9807 | 0.6555 | 0.6324 | 0.017* | |
C10 | 0.9474 (4) | 0.5302 (3) | 0.5286 (2) | 0.0161 (7) | |
H10 | 0.9795 | 0.4725 | 0.5756 | 0.019* | |
C11 | 0.8997 (5) | 0.5065 (2) | 0.4254 (2) | 0.0148 (6) | |
C12 | 0.8517 (4) | 0.5894 (3) | 0.3554 (2) | 0.0153 (7) | |
H12 | 0.8191 | 0.5720 | 0.2851 | 0.018* | |
C13 | 0.8520 (4) | 0.6986 (3) | 0.3898 (2) | 0.0142 (6) | |
H13 | 0.8196 | 0.7560 | 0.3424 | 0.017* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Br1 | 0.02368 (15) | 0.01300 (14) | 0.01890 (13) | −0.00129 (14) | 0.00259 (14) | −0.00242 (13) |
F1 | 0.0229 (10) | 0.0218 (10) | 0.0141 (8) | 0.0003 (8) | 0.0031 (7) | −0.0022 (7) |
F2 | 0.0213 (10) | 0.0185 (10) | 0.0138 (8) | −0.0028 (8) | 0.0029 (7) | 0.0034 (7) |
F3 | 0.0201 (9) | 0.0163 (9) | 0.0125 (7) | 0.0014 (7) | 0.0034 (7) | −0.0004 (8) |
F4 | 0.0265 (10) | 0.0143 (10) | 0.0179 (8) | −0.0015 (7) | 0.0042 (7) | 0.0030 (7) |
N1 | 0.0216 (14) | 0.0193 (15) | 0.0215 (12) | 0.0015 (14) | 0.0011 (13) | −0.0013 (11) |
C1 | 0.0153 (14) | 0.0200 (15) | 0.0130 (13) | −0.0011 (13) | 0.0005 (14) | 0.0010 (11) |
C2 | 0.0156 (13) | 0.0137 (14) | 0.0165 (13) | 0.0012 (14) | −0.0020 (13) | −0.0026 (11) |
C3 | 0.0133 (15) | 0.0204 (18) | 0.0125 (13) | 0.0020 (13) | −0.0003 (11) | −0.0034 (12) |
C4 | 0.0121 (13) | 0.0149 (16) | 0.0169 (13) | −0.0017 (11) | −0.0013 (12) | 0.0049 (14) |
C5 | 0.0112 (12) | 0.0144 (15) | 0.0136 (11) | 0.0014 (14) | −0.0040 (12) | −0.0006 (11) |
C6 | 0.0110 (14) | 0.0162 (16) | 0.0116 (13) | 0.0024 (12) | −0.0007 (11) | −0.0012 (12) |
C7 | 0.0136 (14) | 0.0138 (16) | 0.0160 (14) | 0.0003 (12) | −0.0008 (11) | 0.0035 (12) |
C8 | 0.0101 (13) | 0.0134 (15) | 0.0164 (12) | −0.0001 (13) | 0.0009 (13) | −0.0013 (11) |
C9 | 0.0117 (14) | 0.0187 (16) | 0.0133 (12) | −0.0030 (13) | −0.0021 (10) | −0.0017 (14) |
C10 | 0.0155 (17) | 0.0149 (16) | 0.0178 (14) | 0.0010 (12) | 0.0008 (12) | 0.0033 (13) |
C11 | 0.0125 (13) | 0.0136 (15) | 0.0183 (13) | −0.0029 (14) | 0.0017 (14) | −0.0048 (11) |
C12 | 0.0147 (16) | 0.0191 (17) | 0.0120 (14) | −0.0006 (12) | 0.0002 (10) | −0.0025 (12) |
C13 | 0.0136 (15) | 0.0151 (15) | 0.0137 (13) | 0.0018 (11) | −0.0005 (11) | 0.0045 (12) |
Br1—C11 | 1.892 (3) | C5—C8 | 1.487 (4) |
F1—C3 | 1.346 (3) | C6—C7 | 1.379 (4) |
F2—C4 | 1.339 (3) | C8—C9 | 1.400 (4) |
F3—C6 | 1.347 (3) | C8—C13 | 1.406 (4) |
F4—C7 | 1.336 (3) | C9—C10 | 1.383 (4) |
N1—C1 | 1.150 (4) | C9—H9 | 0.9500 |
C1—C2 | 1.438 (4) | C10—C11 | 1.389 (4) |
C2—C7 | 1.393 (4) | C10—H10 | 0.9500 |
C2—C3 | 1.402 (4) | C11—C12 | 1.388 (4) |
C3—C4 | 1.377 (4) | C12—C13 | 1.392 (4) |
C4—C5 | 1.409 (4) | C12—H12 | 0.9500 |
C5—C6 | 1.401 (4) | C13—H13 | 0.9500 |
N1—C1—C2 | 178.1 (3) | C9—C8—C13 | 118.6 (3) |
C7—C2—C3 | 117.1 (3) | C9—C8—C5 | 121.2 (2) |
C7—C2—C1 | 122.1 (3) | C13—C8—C5 | 120.3 (3) |
C3—C2—C1 | 120.8 (2) | C10—C9—C8 | 121.1 (3) |
F1—C3—C4 | 119.3 (3) | C10—C9—H9 | 119.4 |
F1—C3—C2 | 119.1 (3) | C8—C9—H9 | 119.4 |
C4—C3—C2 | 121.6 (3) | C9—C10—C11 | 119.2 (3) |
F2—C4—C3 | 118.0 (3) | C9—C10—H10 | 120.4 |
F2—C4—C5 | 120.1 (3) | C11—C10—H10 | 120.4 |
C3—C4—C5 | 121.9 (3) | C12—C11—C10 | 121.4 (3) |
C6—C5—C4 | 115.5 (3) | C12—C11—Br1 | 119.1 (2) |
C6—C5—C8 | 122.5 (2) | C10—C11—Br1 | 119.5 (2) |
C4—C5—C8 | 122.0 (3) | C11—C12—C13 | 119.0 (3) |
F3—C6—C7 | 117.1 (3) | C11—C12—H12 | 120.5 |
F3—C6—C5 | 119.8 (3) | C13—C12—H12 | 120.5 |
C7—C6—C5 | 123.0 (3) | C12—C13—C8 | 120.7 (3) |
F4—C7—C6 | 119.3 (3) | C12—C13—H13 | 119.6 |
F4—C7—C2 | 119.8 (3) | C8—C13—H13 | 119.6 |
C6—C7—C2 | 120.9 (3) | ||
C7—C2—C3—F1 | 179.9 (3) | C5—C6—C7—C2 | 0.2 (5) |
C1—C2—C3—F1 | −0.5 (4) | C3—C2—C7—F4 | −179.4 (3) |
C7—C2—C3—C4 | 0.1 (5) | C1—C2—C7—F4 | 1.0 (5) |
C1—C2—C3—C4 | 179.7 (3) | C3—C2—C7—C6 | −0.3 (4) |
F1—C3—C4—F2 | 2.6 (4) | C1—C2—C7—C6 | −179.9 (3) |
C2—C3—C4—F2 | −177.5 (3) | C6—C5—C8—C9 | 139.2 (3) |
F1—C3—C4—C5 | −179.5 (3) | C4—C5—C8—C9 | −40.8 (4) |
C2—C3—C4—C5 | 0.3 (5) | C6—C5—C8—C13 | −40.4 (5) |
F2—C4—C5—C6 | 177.3 (3) | C4—C5—C8—C13 | 139.6 (3) |
C3—C4—C5—C6 | −0.5 (4) | C13—C8—C9—C10 | −0.3 (4) |
F2—C4—C5—C8 | −2.6 (4) | C5—C8—C9—C10 | −179.9 (3) |
C3—C4—C5—C8 | 179.6 (3) | C8—C9—C10—C11 | 0.3 (4) |
C4—C5—C6—F3 | 177.6 (2) | C9—C10—C11—C12 | −0.2 (5) |
C8—C5—C6—F3 | −2.4 (4) | C9—C10—C11—Br1 | −179.8 (2) |
C4—C5—C6—C7 | 0.2 (4) | C10—C11—C12—C13 | 0.1 (5) |
C8—C5—C6—C7 | −179.8 (3) | Br1—C11—C12—C13 | 179.7 (2) |
F3—C6—C7—F4 | 1.8 (4) | C11—C12—C13—C8 | −0.1 (4) |
C5—C6—C7—F4 | 179.3 (3) | C9—C8—C13—C12 | 0.2 (4) |
F3—C6—C7—C2 | −177.3 (3) | C5—C8—C13—C12 | 179.8 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
C9—H9···F2 | 0.95 | 2.47 | 2.882 (4) | 106 |
C13—H13···F3 | 0.95 | 2.45 | 2.865 (3) | 107 |
D—H···A | D—H | H···A | D···A | D—H···A |
C9—H9···F2 | 0.95 | 2.47 | 2.882 (4) | 106.3 |
C13—H13···F3 | 0.95 | 2.45 | 2.865 (3) | 106.6 |
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