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ISSN: 2056-9890

N-Benzyl-2,3,4,5,6-penta­fluoro­benz­amide

aNanoscience Center, Department of Chemistry, University of Jyväskylä, PO Box 35, FIN-40014 University of Jyväskylä, Finland
*Correspondence e-mail: kari.t.rissanen@jyu.fi

(Received 15 October 2010; accepted 24 October 2010; online 31 October 2010)

In the title compound, C14H8F5NO, the dihedral angle between the planes of the penta­fluoro­phenyl and phenyl rings is 18.34 (5)°. An inter­molecular N—H⋯O hydrogen bond between the amide groups connects these mol­ecules to form an infinite chain through the crystal structure. One weak intermolecular C—H⋯O contact and one ππ interaction [centroid–centroid distance = 3.772 (3) Å] are also involved in crystal structure stabilization between the phenyl rings.

Related literature

For related structures, see: An & Rhee (2003[An, G. & Rhee, H. (2003). Synlett, pp. 876-878.]); Cockroft et al. (2007[Cockroft, S. L., Perkins, J., Zonta, C., Adams, H., Spey, S. E., Low, C. M. R., Vinter, J. G., Lawson, K. R., Urch, C. J. & Hunter, C. A. (2007). Org. Biomol. Chem. 5, 1062-1080.]); Forbes et al. (2001[Forbes, C. C., Beatty, A. M. & Smith, B. D. (2001). Org. Lett. 3, 3595-3598.]); Liu et al. (2007[Liu, S.-L., Liang, E.-X., Yu, L.-C. & Huang, L. (2007). Z. Kristallogr. New Cryst. Struct. 222, 433-434.]); Qadeer et al. (2007[Qadeer, G., Rama, N. H. & Wong, W.-Y. (2007). Acta Cryst. E63, o335-o336.]); Zhang & Zhang (2008[Zhang, Q.-X. & Zhang, B.-S. (2008). Acta Cryst. E64, o884.]). For anion⋯π inter­actions, see: Albrecht et al. (2010[Albrecht, M., Müller, M., Mergel, O., Rissanen, K. & Valkonen, A. (2010). Chem. Eur. J. 16, 5062-5069.]); Lahtinen & Rissanen (2007[Lahtinen, T. & Rissanen, K. (2007). Acta Cryst. E63, o4114.]); Müller et al. (2010[Müller, M., Albrecht, M., Gossen, V., Peters, T., Hoffmann, A., Raabe, G., Valkonen, A. & Rissanen, K. (2010). Chem. Eur. J. In the press.]).

[Scheme 1]

Experimental

Crystal data
  • C14H8F5NO

  • Mr = 301.21

  • Monoclinic, P 21 /n

  • a = 7.1649 (2) Å

  • b = 22.9090 (5) Å

  • c = 7.5363 (1) Å

  • β = 99.205 (2)°

  • V = 1221.08 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.16 mm−1

  • T = 123 K

  • 0.40 × 0.28 × 0.26 mm

Data collection
  • Bruker Nonius KappaCCD with APEXII detector diffractometer

  • 4246 measured reflections

  • 2152 independent reflections

  • 1891 reflections with I > 2σ(I)

  • Rint = 0.016

Refinement
  • R[F2 > 2σ(F2)] = 0.033

  • wR(F2) = 0.086

  • S = 1.06

  • 2152 reflections

  • 193 parameters

  • 1 restraint

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.20 e Å−3

  • Δρmin = −0.18 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N8—H8⋯O1i 0.88 (1) 2.01 (1) 2.875 (2) 171 (2)
C5—H5⋯O1ii 0.95 2.37 3.276 (2) 158
Symmetry codes: (i) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (ii) x, y, z+1.

Data collection: COLLECT (Bruker, 2008[Bruker (2008). COLLECT. Bruker AXS Inc., Delft, The Netherlands.]); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO-SMN; program(s) used to solve structure: SIR2004 (Burla et al., 2005[Burla, M. C., Caliandro, R., Camalli, M., Carrozzini, B., Cascarano, G. L., De Caro, L., Giacovazzo, C., Polidori, G. & Spagna, R. (2005). J. Appl. Cryst. 38, 381-388.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

The title compound is synthesized by classical amide formation reaction between amine (benzylamine) and carboxylic acid halide (2,3,4,5,6-pentafluorobenzoylchloride). The molecule of this secondary amide is not planar and contains two aromatic ring systems (Fig. 1), the other one being electron poor due to electron-withdrawing force of connected F atoms. This pentafluorophenyl moiety has recently been found to be an excellent halogen···π contact acceptor for halide and polyhalide anions in similar ammonium salt structures (Albrecht et al., 2010; Müller et al., 2010) and also acceptor for CO···C(aromatic) anion···.π-type contacts (Lahtinen & Rissanen, 2007). The pentafluorophenyl ring is found to be inclined to phenyl ring by 18.34 (5)°. The C10/C9/N8/O1 amide group is more significantly inclined to pentafluorophenyl ring by 56.95 (4)° and to phenyl ring by 56.21 (4)°, as also observed, for example, with few substituted N-phenyl-2,3,4,5,6-pentafluorobenzamides (Cockroft et al., 2007) and N-Benzyl-4,5-dimethoxy-2-nitrobenzamide (Qadeer et al., 2007).

The intermolecular interactions of the title compound include one N—H···O, one C—H···O (Table 1) and one ππ contacts. The N—H···O hydrogen bonds connect the molecules to form infinite chain in (x + 1/2, -y + 1/2, z + 1/2) direction (Fig. 2), where every second molecule is in same orientation and every second is rotated 180° on the direction of b axis. Similar chain was obtained, for example,with N-Benzyl-4-phenylbenzamide (An & Rhee, 2003). These chains are connected to each other by one C—H···O (Table 1) and one ππ contacts (Fig. 3), the latter having centroid-to-centroid distance of 3.772 (3) Å and closest C···C distance of 3.327 (3) Å. These distances are slightly longer than in the structure of N-(2-pyridyl)-2,3,4,5,6-pentafluorobenzamide (Forbes et al., 2001). The CO···C(aromatic) anion···.π-type contact, found from the related structure of N-[1-(silatran-1-yl)propyl]pentaflurobenzamide (Lahtinen & Rissanen, 2007), seems to be in this case forced by nearby N—H···O contact. Fluorines F3 and F4 (Fig. 1) show distance 2.920 (2) Å to F3 and F4 of the neighbouring molecule in (-x, -y, -z + 1) direction, but this contact is most probably too weak to be significant in crystal stabilization.

Related literature top

For related structures, see: An & Rhee (2003); Cockroft et al. (2007); Forbes et al. (2001); Liu et al. (2007); Qadeer et al. (2007); Zhang & Zhang (2008). For anion···π interactions, see: Albrecht et al. (2010); Lahtinen & Rissanen (2007); Müller et al. (2010).

Experimental top

Benzylamine (184 mg, 1.72 mmol) and triethylamine (470µl, 3.44 mmol) were mixed in dry DCM under inert atmosphere (Ar). The reaction mixture was cooled (ice–salt bath) and 2,3,4,5,6-pentafluorobenzoylchloride (240µl, 1.72 mmol) in dry DCM was added dropwise to the reaction mixture. After addition the reaction mixture was stirred in ice–salt bath for 1 h and in room temperature for additional 20 h. The reaction mixture was washed twice with water and organic layer was dried and evaporated to yield white solid product. For the single-crystal X-ray analysis the crude product was recrystallized from CHCl3 yielding colourless needles.

Refinement top

All H atoms were visible in electron density maps, but those bonded to C were ideally positioned and allowed to ride on their parent atoms at C—H distances of 0.95 Å (aromatic) and 0.99 Å (methylene), with Uiso(H) of 1.2 times Ueq(C). The N—H proton were found in the electron density map and was refined with a distance restraint [N—H = 0.88 (2) Å], and Uiso(H) = 1.2 times Ueq(N) was used.

Computing details top

Data collection: COLLECT (Bruker, 2008); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR2004 (Burla et al., 2005); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. View of the molecule of the title compound showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented by circles of arbitrary size.
[Figure 2] Fig. 2. Part of the infinite chain formed by N—H···O hydrogen bonds in the crystal of the title compound.
[Figure 3] Fig. 3. Packing diagram showing the N—H···O, C—H···O and ππ contacts.
N-Benzyl-2,3,4,5,6-pentafluorobenzamide top
Crystal data top
C14H8F5NOF(000) = 608
Mr = 301.21Dx = 1.638 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
a = 7.1649 (2) ÅCell parameters from 3094 reflections
b = 22.9090 (5) Åθ = 0.4–28.3°
c = 7.5363 (1) ŵ = 0.16 mm1
β = 99.205 (2)°T = 123 K
V = 1221.08 (5) Å3Block, colourless
Z = 40.40 × 0.28 × 0.26 mm
Data collection top
Bruker Nonius KappaCCD with APEXII detector
diffractometer
1891 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.016
Graphite monochromatorθmax = 25.0°, θmin = 2.9°
Detector resolution: 9 pixels mm-1h = 88
ϕ and ω scansk = 2727
4246 measured reflectionsl = 88
2152 independent reflections
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)] = 0.033Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.086H atoms treated by a mixture of independent and constrained refinement
S = 1.06 w = 1/[σ2(Fo2) + (0.0393P)2 + 0.498P]
where P = (Fo2 + 2Fc2)/3
2152 reflections(Δ/σ)max < 0.001
193 parametersΔρmax = 0.20 e Å3
1 restraintΔρmin = 0.18 e Å3
Crystal data top
C14H8F5NOV = 1221.08 (5) Å3
Mr = 301.21Z = 4
Monoclinic, P21/nMo Kα radiation
a = 7.1649 (2) ŵ = 0.16 mm1
b = 22.9090 (5) ÅT = 123 K
c = 7.5363 (1) Å0.40 × 0.28 × 0.26 mm
β = 99.205 (2)°
Data collection top
Bruker Nonius KappaCCD with APEXII detector
diffractometer
1891 reflections with I > 2σ(I)
4246 measured reflectionsRint = 0.016
2152 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0331 restraint
wR(F2) = 0.086H atoms treated by a mixture of independent and constrained refinement
S = 1.06Δρmax = 0.20 e Å3
2152 reflectionsΔρmin = 0.18 e Å3
193 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
F10.11992 (14)0.19154 (4)0.04946 (11)0.0315 (2)
F20.17000 (14)0.07495 (4)0.05119 (12)0.0350 (3)
F30.14683 (15)0.01169 (4)0.24882 (14)0.0379 (3)
F40.06766 (15)0.06526 (4)0.54949 (12)0.0363 (3)
F50.00325 (13)0.18090 (4)0.54897 (11)0.0277 (2)
O10.10620 (15)0.27306 (4)0.12572 (13)0.0260 (3)
N80.12659 (19)0.28716 (5)0.36339 (16)0.0232 (3)
H80.218 (2)0.2705 (7)0.437 (2)0.028*
C10.1073 (2)0.37470 (6)0.55552 (19)0.0207 (3)
C20.1399 (2)0.43426 (7)0.5826 (2)0.0240 (3)
H20.16520.45790.48560.029*
C30.1359 (2)0.45945 (7)0.7488 (2)0.0278 (4)
H30.15700.50020.76490.033*
C40.1011 (2)0.42535 (7)0.8916 (2)0.0277 (4)
H40.09830.44251.00590.033*
C50.0703 (2)0.36600 (7)0.8668 (2)0.0262 (4)
H50.04740.34240.96480.031*
C60.0729 (2)0.34078 (7)0.6995 (2)0.0226 (3)
H60.05090.30010.68350.027*
C70.1041 (2)0.35043 (6)0.3685 (2)0.0262 (4)
H7A0.01740.36120.29350.031*
H7B0.20680.36890.31490.031*
C90.0197 (2)0.25426 (6)0.24216 (18)0.0197 (3)
C100.0625 (2)0.18984 (6)0.25080 (18)0.0197 (3)
C110.1035 (2)0.16115 (7)0.09949 (19)0.0224 (3)
C120.1315 (2)0.10168 (7)0.0975 (2)0.0249 (4)
C130.1202 (2)0.06950 (7)0.2499 (2)0.0258 (4)
C140.0806 (2)0.09667 (7)0.4021 (2)0.0253 (4)
C150.0511 (2)0.15619 (7)0.40118 (19)0.0215 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
F10.0414 (6)0.0350 (5)0.0190 (5)0.0003 (4)0.0075 (4)0.0023 (4)
F20.0382 (6)0.0351 (5)0.0326 (5)0.0004 (4)0.0089 (4)0.0129 (4)
F30.0420 (6)0.0199 (5)0.0515 (6)0.0005 (4)0.0070 (5)0.0003 (4)
F40.0463 (6)0.0303 (5)0.0315 (5)0.0016 (4)0.0039 (4)0.0131 (4)
F50.0343 (5)0.0314 (5)0.0176 (4)0.0017 (4)0.0050 (4)0.0009 (4)
O10.0271 (6)0.0248 (6)0.0223 (5)0.0011 (5)0.0072 (5)0.0037 (4)
N80.0258 (7)0.0204 (7)0.0203 (6)0.0035 (5)0.0057 (5)0.0006 (5)
C10.0169 (7)0.0222 (8)0.0215 (7)0.0018 (6)0.0015 (6)0.0001 (6)
C20.0239 (8)0.0241 (8)0.0232 (8)0.0008 (6)0.0016 (6)0.0022 (6)
C30.0255 (8)0.0233 (8)0.0333 (9)0.0014 (7)0.0006 (7)0.0045 (7)
C40.0249 (9)0.0354 (9)0.0227 (8)0.0027 (7)0.0034 (6)0.0067 (7)
C50.0217 (8)0.0350 (9)0.0222 (8)0.0016 (7)0.0046 (6)0.0041 (6)
C60.0209 (8)0.0201 (7)0.0256 (8)0.0005 (6)0.0001 (6)0.0019 (6)
C70.0345 (9)0.0212 (8)0.0212 (8)0.0008 (7)0.0004 (6)0.0009 (6)
C90.0191 (8)0.0242 (8)0.0158 (7)0.0019 (6)0.0025 (6)0.0024 (6)
C100.0148 (7)0.0243 (8)0.0186 (7)0.0017 (6)0.0020 (5)0.0001 (6)
C110.0193 (8)0.0288 (8)0.0184 (7)0.0028 (6)0.0006 (6)0.0028 (6)
C120.0188 (8)0.0291 (8)0.0262 (8)0.0014 (6)0.0017 (6)0.0074 (7)
C130.0212 (8)0.0192 (8)0.0355 (9)0.0010 (6)0.0000 (7)0.0002 (6)
C140.0229 (8)0.0260 (8)0.0256 (8)0.0031 (6)0.0002 (6)0.0074 (6)
C150.0183 (8)0.0269 (8)0.0183 (7)0.0018 (6)0.0008 (6)0.0014 (6)
Geometric parameters (Å, º) top
F1—C111.3419 (17)C3—H30.9500
F2—C121.3439 (18)C4—C51.385 (2)
F3—C131.3381 (18)C4—H40.9500
F4—C141.3393 (17)C5—C61.390 (2)
F5—C151.3418 (17)C5—H50.9500
O1—C91.2313 (17)C6—H60.9500
N8—C91.3287 (19)C7—H7A0.9900
N8—C71.4596 (19)C7—H7B0.9900
N8—H80.876 (14)C9—C101.507 (2)
C1—C61.388 (2)C10—C151.384 (2)
C1—C21.394 (2)C10—C111.388 (2)
C1—C71.512 (2)C11—C121.377 (2)
C2—C31.383 (2)C12—C131.378 (2)
C2—H20.9500C13—C141.374 (2)
C3—C41.385 (2)C14—C151.380 (2)
C9—N8—C7121.84 (13)N8—C7—H7B108.8
C9—N8—H8118.6 (11)C1—C7—H7B108.8
C7—N8—H8119.4 (11)H7A—C7—H7B107.7
C6—C1—C2118.69 (14)O1—C9—N8124.59 (14)
C6—C1—C7122.99 (13)O1—C9—C10119.63 (13)
C2—C1—C7118.28 (13)N8—C9—C10115.78 (12)
C3—C2—C1120.92 (14)C15—C10—C11117.21 (14)
C3—C2—H2119.5C15—C10—C9122.86 (13)
C1—C2—H2119.5C11—C10—C9119.79 (13)
C2—C3—C4120.05 (14)F1—C11—C12118.15 (13)
C2—C3—H3120.0F1—C11—C10120.00 (14)
C4—C3—H3120.0C12—C11—C10121.84 (14)
C3—C4—C5119.56 (14)F2—C12—C11120.61 (14)
C3—C4—H4120.2F2—C12—C13119.90 (14)
C5—C4—H4120.2C11—C12—C13119.49 (14)
C4—C5—C6120.37 (14)F3—C13—C14120.15 (14)
C4—C5—H5119.8F3—C13—C12119.81 (14)
C6—C5—H5119.8C14—C13—C12120.04 (14)
C1—C6—C5120.40 (14)F4—C14—C13119.99 (14)
C1—C6—H6119.8F4—C14—C15120.27 (14)
C5—C6—H6119.8C13—C14—C15119.73 (14)
N8—C7—C1113.87 (12)F5—C15—C14118.18 (13)
N8—C7—H7A108.8F5—C15—C10120.08 (13)
C1—C7—H7A108.8C14—C15—C10121.69 (14)
C6—C1—C2—C30.8 (2)F1—C11—C12—F21.4 (2)
C7—C1—C2—C3177.02 (14)C10—C11—C12—F2179.65 (13)
C1—C2—C3—C40.7 (2)F1—C11—C12—C13178.39 (13)
C2—C3—C4—C50.0 (2)C10—C11—C12—C130.6 (2)
C3—C4—C5—C60.5 (2)F2—C12—C13—F30.3 (2)
C2—C1—C6—C50.3 (2)C11—C12—C13—F3179.87 (14)
C7—C1—C6—C5177.44 (14)F2—C12—C13—C14179.91 (14)
C4—C5—C6—C10.4 (2)C11—C12—C13—C140.3 (2)
C9—N8—C7—C1135.84 (15)F3—C13—C14—F40.3 (2)
C6—C1—C7—N819.9 (2)C12—C13—C14—F4179.26 (13)
C2—C1—C7—N8162.42 (14)F3—C13—C14—C15179.20 (14)
C7—N8—C9—O10.4 (2)C12—C13—C14—C150.4 (2)
C7—N8—C9—C10178.57 (13)F4—C14—C15—F52.2 (2)
O1—C9—C10—C15121.13 (16)C13—C14—C15—F5176.69 (13)
N8—C9—C10—C1559.85 (19)F4—C14—C15—C10179.71 (13)
O1—C9—C10—C1154.5 (2)C13—C14—C15—C100.8 (2)
N8—C9—C10—C11124.55 (15)C11—C10—C15—F5176.90 (12)
C15—C10—C11—F1178.80 (13)C9—C10—C15—F51.2 (2)
C9—C10—C11—F15.4 (2)C11—C10—C15—C140.5 (2)
C15—C10—C11—C120.1 (2)C9—C10—C15—C14176.25 (14)
C9—C10—C11—C12175.70 (14)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N8—H8···O1i0.88 (1)2.01 (1)2.875 (2)171 (2)
C5—H5···O1ii0.952.373.276 (2)158
Symmetry codes: (i) x+1/2, y+1/2, z+1/2; (ii) x, y, z+1.

Experimental details

Crystal data
Chemical formulaC14H8F5NO
Mr301.21
Crystal system, space groupMonoclinic, P21/n
Temperature (K)123
a, b, c (Å)7.1649 (2), 22.9090 (5), 7.5363 (1)
β (°) 99.205 (2)
V3)1221.08 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.16
Crystal size (mm)0.40 × 0.28 × 0.26
Data collection
DiffractometerBruker Nonius KappaCCD with APEXII detector
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
4246, 2152, 1891
Rint0.016
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.033, 0.086, 1.06
No. of reflections2152
No. of parameters193
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.20, 0.18

Computer programs: COLLECT (Bruker, 2008), DENZO-SMN (Otwinowski & Minor, 1997), SIR2004 (Burla et al., 2005), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N8—H8···O1i0.876 (14)2.007 (14)2.875 (2)171 (2)
C5—H5···O1ii0.952.373.276 (2)158.4
Symmetry codes: (i) x+1/2, y+1/2, z+1/2; (ii) x, y, z+1.
 

Acknowledgements

This work was supported by the Academy of Finland (KR, project No. 212588).

References

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