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

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ISSN: 2056-9890

N-(4-Cyano­phen­yl)-2,6-di­fluoro­benzamide

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bDepartment of Studies in Chemistry, Mangalore University, Mangalagangotri, Mangalore 574 199, India
*Correspondence e-mail: hkfun@usm.my

(Received 9 November 2010; accepted 10 November 2010; online 17 November 2010)

In the title compound, C14H8F2N2O, the amide plane is inclined at dihedral angles of 28.12 (12) and 32.89 (12)° with respect to the two benzene rings; the dihedral angle between the two rings is 5.58 (5)°. In the crystal, inter­molecular N—H⋯O and C—H⋯F hydrogen bonds link adjacent mol­ecules into a double-chain structure along the b axis.

Related literature

For general background to and applications of the title compound, see: Ashwood et al. (1990[Ashwood, V. A., Cassidy, F., Coldwell, M. C., Evans, J. M., Hamilton, T. C., Howlett, D. R., Smith, D. M. & Stemp, G. (1990). J. Med. Chem. 33, 2667-2672.]); Kees et al. (1989[Kees, K. L., Cheeseman, R. S., Prozialeck, D. H. & Steiner, K. E. (1989). J. Med. Chem. 32, 11-13.]); Ragavan et al. (2010[Ragavan, R. V., Vijayakumar, V. & Suchetha Kumari, N. (2010). Eur. J. Med. Chem. 43, 1173-1180.]); Carmellino et al. (1994[Carmellino, M. L., Pagani, G., Pregnolato, M., Terreni, M. & Pastoni, F. (1994). Eur. J. Med. Chem. 29, 743-751.]); Rauko et al. (2001[Rauko, P., Novotny, L., Dovinova, I., Hunakova, L., Szekeres, T. & Jayaram, H. N. (2001). Eur. J. Pharm. Sci. 12, 387-394.]). For a closely related benzamide structure, see: Cronin et al. (2000[Cronin, L., Adams, D. A., Nightingale, D. J. & Clark, J. H. (2000). Acta Cryst. C56, 244-245.]). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986[Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105-107.]).

[Scheme 1]

Experimental

Crystal data
  • C14H8F2N2O

  • Mr = 258.22

  • Monoclinic, P 21 /c

  • a = 9.3377 (11) Å

  • b = 5.0793 (6) Å

  • c = 24.500 (3) Å

  • β = 100.202 (3)°

  • V = 1143.6 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.12 mm−1

  • T = 100 K

  • 0.27 × 0.14 × 0.14 mm

Data collection
  • Bruker APEXII DUO CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.968, Tmax = 0.984

  • 27219 measured reflections

  • 4135 independent reflections

  • 3176 reflections with I > 2σ(I)

  • Rint = 0.054

Refinement
  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.118

  • S = 1.03

  • 4135 reflections

  • 204 parameters

  • All H-atom parameters refined

  • Δρmax = 0.39 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1N1⋯O1i 0.863 (15) 2.107 (15) 2.9029 (12) 153.3 (14)
C12—H12⋯F1ii 0.940 (16) 2.473 (16) 3.4066 (14) 172.4 (13)
Symmetry codes: (i) x, y+1, z; (ii) -x+1, -y, -z.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

A number of benzamide derivatives were reported as anti-hypertensive (Ashwood et al., 1990), anti-diabetic (Kees et al., 1989), anti-bacterial (Ragavan et al., 2010), anti-fungal (Carmellino et al., 1994) and anti-cancer (Rauko et al., 2001) activities. On the basis of these considerations, our particular attention was paid for the synthesis of some benzamide derivatives.

In the title benzamide derivative, the amino moiety (C7/N1/O1) is essentially planar, as indicated by the C7–O1–N1–H1N1 torsion angle of -1.4 (18)°. The mean plane through the amido moiety is inclined at dihedral angles of 32.89 (12) and 28.12 (12)°, respectively, with the C1–C6 and C8–C13 benzene rings. The dihedral angle between the two benzene rings being 5.58 (5)°. All bond lengths and angles are comparable to values observed in a closely related benzamide structure (Cronin et al., 2000). In the crystal packing, adjacent molecules are interconnected into two-molecule-wide infinite chains propagating along the [010] direction (Fig. 2) via intermolecular N1—H1N1···O1 and C12—H12···F1 hydrogen bonds (Table 1).

Related literature top

For general background to and applications of the title compound, see: Ashwood et al. (1990); Kees et al. (1989); Ragavan et al. (2010); Carmellino et al. (1994); Rauko et al. (2001). For a closely related benzamide structure, see: Cronin et al. (2000). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

Experimental top

A mixture of 4-amino benzonitrile (4.2 mmol), 2,6-difluorobenzoic acid (4.6 mmol) and triethyl amine (21 mmol) was dissolved in methylene dichloride (5 ml). The resulting solution was cooled to 273 K followed by the drop wise addition of 50 % phosphoric acid cyclic anhydride solution in ethyl acetate (4 ml, 6.3 mmol) and stirred for 12 h. The completion of reaction was checked by TLC. Evaporation of solvent gave 2,6-difluoro-N-(p-cyanophenyl)benzamide as solid mass, which was then stirred with saturated NaHCO3 solution to remove excess of acid. Single crystals suitable for X-ray analysis were obtained by crystallization from acetone under slow evaporation. M.p. 418 K.

Refinement top

All H atoms were located from a difference Fourier map and allowed to refine freely [refined distances: N—H = 0.860 (16) Å and C—H = 0.933 (15)–0.984 (15) Å].

Structure description top

A number of benzamide derivatives were reported as anti-hypertensive (Ashwood et al., 1990), anti-diabetic (Kees et al., 1989), anti-bacterial (Ragavan et al., 2010), anti-fungal (Carmellino et al., 1994) and anti-cancer (Rauko et al., 2001) activities. On the basis of these considerations, our particular attention was paid for the synthesis of some benzamide derivatives.

In the title benzamide derivative, the amino moiety (C7/N1/O1) is essentially planar, as indicated by the C7–O1–N1–H1N1 torsion angle of -1.4 (18)°. The mean plane through the amido moiety is inclined at dihedral angles of 32.89 (12) and 28.12 (12)°, respectively, with the C1–C6 and C8–C13 benzene rings. The dihedral angle between the two benzene rings being 5.58 (5)°. All bond lengths and angles are comparable to values observed in a closely related benzamide structure (Cronin et al., 2000). In the crystal packing, adjacent molecules are interconnected into two-molecule-wide infinite chains propagating along the [010] direction (Fig. 2) via intermolecular N1—H1N1···O1 and C12—H12···F1 hydrogen bonds (Table 1).

For general background to and applications of the title compound, see: Ashwood et al. (1990); Kees et al. (1989); Ragavan et al. (2010); Carmellino et al. (1994); Rauko et al. (2001). For a closely related benzamide structure, see: Cronin et al. (2000). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 50 % probability displacement ellipsoids for non-H atoms and the atom-numbering scheme.
[Figure 2] Fig. 2. The crystal structure of the title compound, viewed along the a axis, showing two-molecule-wide infinite chains along the [010] direction. H atoms not involved in intermolecular hydrogen bonds (dashed lines) have been omitted for clarity.
N-(4-Cyanophenyl)-2,6-difluorobenzamide top
Crystal data top
C14H8F2N2OF(000) = 528
Mr = 258.22Dx = 1.500 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 5020 reflections
a = 9.3377 (11) Åθ = 2.2–31.3°
b = 5.0793 (6) ŵ = 0.12 mm1
c = 24.500 (3) ÅT = 100 K
β = 100.202 (3)°Block, yellow
V = 1143.6 (2) Å30.27 × 0.14 × 0.14 mm
Z = 4
Data collection top
Bruker APEXII DUO CCD area-detector
diffractometer
4135 independent reflections
Radiation source: fine-focus sealed tube3176 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.054
φ and ω scansθmax = 32.6°, θmin = 2.2°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 1414
Tmin = 0.968, Tmax = 0.984k = 77
27219 measured reflectionsl = 3637
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)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.118All H-atom parameters refined
S = 1.03 w = 1/[σ2(Fo2) + (0.0568P)2 + 0.2429P]
where P = (Fo2 + 2Fc2)/3
4135 reflections(Δ/σ)max < 0.001
204 parametersΔρmax = 0.39 e Å3
0 restraintsΔρmin = 0.23 e Å3
Crystal data top
C14H8F2N2OV = 1143.6 (2) Å3
Mr = 258.22Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.3377 (11) ŵ = 0.12 mm1
b = 5.0793 (6) ÅT = 100 K
c = 24.500 (3) Å0.27 × 0.14 × 0.14 mm
β = 100.202 (3)°
Data collection top
Bruker APEXII DUO CCD area-detector
diffractometer
4135 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
3176 reflections with I > 2σ(I)
Tmin = 0.968, Tmax = 0.984Rint = 0.054
27219 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0430 restraints
wR(F2) = 0.118All H-atom parameters refined
S = 1.03Δρmax = 0.39 e Å3
4135 reflectionsΔρmin = 0.23 e Å3
204 parameters
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1)K.

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
F10.81277 (8)0.06726 (14)0.14252 (3)0.03127 (18)
F21.02229 (7)0.75952 (13)0.05423 (3)0.02670 (16)
O10.76102 (9)0.12482 (15)0.03141 (3)0.02539 (18)
N10.75319 (9)0.56187 (17)0.01066 (3)0.01774 (17)
N20.33842 (13)0.5436 (2)0.24586 (5)0.0384 (3)
C10.91364 (12)0.2568 (2)0.14216 (4)0.0207 (2)
C21.01589 (13)0.2889 (2)0.18972 (5)0.0252 (2)
C31.11850 (12)0.4873 (2)0.19138 (5)0.0246 (2)
C41.11804 (11)0.6494 (2)0.14589 (5)0.0228 (2)
C51.01538 (11)0.6060 (2)0.09898 (4)0.01910 (19)
C60.90844 (10)0.41080 (19)0.09449 (4)0.01688 (18)
C70.80070 (11)0.35107 (19)0.04285 (4)0.01768 (19)
C80.66236 (11)0.55108 (19)0.04175 (4)0.01768 (19)
C90.67895 (12)0.7489 (2)0.07969 (4)0.0207 (2)
C100.59456 (12)0.7492 (2)0.13217 (5)0.0224 (2)
C110.49135 (11)0.5511 (2)0.14682 (4)0.0220 (2)
C120.47172 (12)0.3569 (2)0.10873 (5)0.0231 (2)
C130.55706 (11)0.3555 (2)0.05623 (4)0.0209 (2)
C140.40564 (13)0.5474 (2)0.20187 (5)0.0275 (2)
H1N10.7848 (16)0.716 (3)0.0216 (6)0.031 (4)*
H21.0120 (16)0.173 (3)0.2194 (6)0.031 (4)*
H31.1931 (16)0.507 (3)0.2249 (6)0.031 (4)*
H41.1877 (17)0.787 (3)0.1456 (6)0.028 (4)*
H90.7526 (15)0.877 (3)0.0683 (6)0.022 (3)*
H100.6115 (15)0.879 (3)0.1573 (6)0.026 (4)*
H120.3999 (17)0.227 (3)0.1180 (6)0.031 (4)*
H130.5408 (15)0.221 (3)0.0309 (6)0.026 (4)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
F10.0336 (4)0.0283 (4)0.0293 (4)0.0134 (3)0.0015 (3)0.0072 (3)
F20.0242 (3)0.0266 (3)0.0274 (3)0.0063 (3)0.0006 (3)0.0092 (3)
O10.0327 (4)0.0133 (3)0.0260 (4)0.0007 (3)0.0061 (3)0.0027 (3)
N10.0212 (4)0.0123 (4)0.0175 (4)0.0004 (3)0.0026 (3)0.0018 (3)
N20.0415 (6)0.0392 (6)0.0283 (5)0.0086 (5)0.0108 (5)0.0071 (5)
C10.0227 (5)0.0172 (5)0.0215 (5)0.0029 (4)0.0021 (4)0.0004 (3)
C20.0283 (5)0.0265 (5)0.0195 (5)0.0012 (4)0.0011 (4)0.0017 (4)
C30.0235 (5)0.0285 (6)0.0198 (5)0.0004 (4)0.0018 (4)0.0042 (4)
C40.0190 (5)0.0222 (5)0.0257 (5)0.0025 (4)0.0003 (4)0.0029 (4)
C50.0187 (4)0.0174 (4)0.0206 (4)0.0002 (3)0.0020 (3)0.0004 (3)
C60.0173 (4)0.0145 (4)0.0179 (4)0.0004 (3)0.0007 (3)0.0023 (3)
C70.0188 (4)0.0144 (4)0.0187 (4)0.0009 (3)0.0002 (3)0.0014 (3)
C80.0186 (4)0.0156 (4)0.0176 (4)0.0020 (3)0.0003 (3)0.0030 (3)
C90.0240 (5)0.0170 (4)0.0194 (5)0.0008 (4)0.0007 (4)0.0015 (3)
C100.0264 (5)0.0202 (5)0.0189 (5)0.0021 (4)0.0002 (4)0.0006 (4)
C110.0214 (5)0.0226 (5)0.0195 (5)0.0049 (4)0.0037 (4)0.0055 (4)
C120.0196 (5)0.0206 (5)0.0266 (5)0.0003 (4)0.0030 (4)0.0051 (4)
C130.0206 (5)0.0181 (5)0.0224 (5)0.0004 (4)0.0008 (4)0.0012 (4)
C140.0279 (5)0.0259 (5)0.0254 (5)0.0056 (4)0.0043 (4)0.0057 (4)
Geometric parameters (Å, º) top
F1—C11.3480 (12)C4—H40.956 (15)
F2—C51.3563 (12)C5—C61.3975 (14)
O1—C71.2246 (12)C6—C71.5014 (13)
N1—C71.3569 (13)C8—C91.3961 (14)
N1—C81.4091 (12)C8—C131.3985 (14)
N1—H1N10.860 (16)C9—C101.3839 (15)
N2—C141.1474 (15)C9—H90.953 (14)
C1—C21.3791 (15)C10—C111.3955 (15)
C1—C61.3992 (14)C10—H100.933 (15)
C2—C31.3861 (16)C11—C121.3922 (16)
C2—H20.943 (15)C11—C141.4414 (15)
C3—C41.3849 (16)C12—C131.3880 (15)
C3—H30.984 (15)C12—H120.939 (15)
C4—C51.3777 (14)C13—H130.952 (15)
C7—N1—C8125.52 (8)O1—C7—C6120.86 (9)
C7—N1—H1N1118.5 (10)N1—C7—C6115.57 (8)
C8—N1—H1N1115.9 (10)C9—C8—C13119.89 (9)
F1—C1—C2117.31 (9)C9—C8—N1117.32 (9)
F1—C1—C6118.94 (9)C13—C8—N1122.78 (9)
C2—C1—C6123.75 (10)C10—C9—C8120.48 (10)
C1—C2—C3118.83 (10)C10—C9—H9122.3 (8)
C1—C2—H2117.6 (9)C8—C9—H9117.2 (8)
C3—C2—H2123.6 (9)C9—C10—C11119.47 (10)
C4—C3—C2120.33 (10)C9—C10—H10118.6 (9)
C4—C3—H3120.8 (9)C11—C10—H10121.9 (9)
C2—C3—H3118.8 (9)C12—C11—C10120.36 (9)
C5—C4—C3118.60 (10)C12—C11—C14120.06 (10)
C5—C4—H4119.0 (9)C10—C11—C14119.58 (10)
C3—C4—H4122.3 (9)C13—C12—C11120.18 (10)
F2—C5—C4117.17 (9)C13—C12—H12119.3 (9)
F2—C5—C6118.68 (9)C11—C12—H12120.5 (9)
C4—C5—C6124.13 (10)C12—C13—C8119.60 (10)
C5—C6—C1114.34 (9)C12—C13—H13118.5 (9)
C5—C6—C7124.92 (9)C8—C13—H13121.9 (9)
C1—C6—C7120.62 (9)N2—C14—C11179.41 (13)
O1—C7—N1123.57 (9)
F1—C1—C2—C3178.04 (10)C1—C6—C7—O131.41 (15)
C6—C1—C2—C31.20 (18)C5—C6—C7—N135.04 (14)
C1—C2—C3—C40.17 (18)C1—C6—C7—N1149.05 (10)
C2—C3—C4—C51.07 (17)C7—N1—C8—C9149.79 (11)
C3—C4—C5—F2176.83 (10)C7—N1—C8—C1331.27 (16)
C3—C4—C5—C61.43 (17)C13—C8—C9—C101.75 (16)
F2—C5—C6—C1177.77 (9)N1—C8—C9—C10179.28 (10)
C4—C5—C6—C10.47 (15)C8—C9—C10—C110.62 (16)
F2—C5—C6—C71.63 (15)C9—C10—C11—C120.98 (16)
C4—C5—C6—C7176.61 (10)C9—C10—C11—C14178.58 (10)
F1—C1—C6—C5178.35 (9)C10—C11—C12—C131.44 (16)
C2—C1—C6—C50.88 (16)C14—C11—C12—C13178.11 (10)
F1—C1—C6—C75.33 (15)C11—C12—C13—C80.31 (16)
C2—C1—C6—C7175.44 (10)C9—C8—C13—C121.28 (16)
C8—N1—C7—O15.34 (17)N1—C8—C13—C12179.81 (10)
C8—N1—C7—C6174.18 (9)C7—O1—N1—H1N11.4 (18)
C5—C6—C7—O1144.50 (11)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N1···O1i0.863 (15)2.107 (15)2.9029 (12)153.3 (14)
C12—H12···F1ii0.940 (16)2.473 (16)3.4066 (14)172.4 (13)
Symmetry codes: (i) x, y+1, z; (ii) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC14H8F2N2O
Mr258.22
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)9.3377 (11), 5.0793 (6), 24.500 (3)
β (°) 100.202 (3)
V3)1143.6 (2)
Z4
Radiation typeMo Kα
µ (mm1)0.12
Crystal size (mm)0.27 × 0.14 × 0.14
Data collection
DiffractometerBruker APEXII DUO CCD area-detector
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.968, 0.984
No. of measured, independent and
observed [I > 2σ(I)] reflections
27219, 4135, 3176
Rint0.054
(sin θ/λ)max1)0.758
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.043, 0.118, 1.03
No. of reflections4135
No. of parameters204
H-atom treatmentAll H-atom parameters refined
Δρmax, Δρmin (e Å3)0.39, 0.23

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N1···O1i0.863 (15)2.107 (15)2.9029 (12)153.3 (14)
C12—H12···F1ii0.940 (16)2.473 (16)3.4066 (14)172.4 (13)
Symmetry codes: (i) x, y+1, z; (ii) x+1, y, z.
 

Footnotes

Thomson Reuters ResearcherID: A-3561-2009.

§Thomson Reuters ResearcherID: C-7576-2009.

Acknowledgements

The authors thank Universiti Sains Malaysia (USM) for the Research University Grant (No. 1001/PFIZIK/811160).

References

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