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

Fun, H.-K.; Goh, J.H.; Gowda, J.; Khader, A.M.; Kalluraya, B.

doi:10.1107/S1600536810046507

organic compounds

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ISSN: 2056-9890

Volume 66| Part 12| December 2010| Page o3192

https://doi.org/10.1107/S1600536810046507

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

Hoong-Kun Fun,^a ^*‡ Jia Hao Goh,^a § Janardhana Gowda,^b A. M. Khader ^b and B. Kalluraya ^b

^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 ); 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

Crystal data

C₁₄H₈F₂N₂O
M_r = 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 ) T_min = 0.968, T_max = 0.984
27219 measured reflections
4135 independent reflections
3176 reflections with I > 2σ(I)
R_int = 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
Δρ_max = 0.39 e Å⁻³
Δρ_min = −0.23 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	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); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536810046507/is2630sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810046507/is2630Isup2.hkl

checkCIF report

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.

Structure description 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).

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

	Fig. 1. The molecular structure of the title compound, showing 50 % probability displacement ellipsoids for non-H atoms and the atom-numbering scheme.
	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

C₁₄H₈F₂N₂O	F(000) = 528
M_r = 258.22	D_x = 1.500 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 5020 reflections
a = 9.3377 (11) Å	θ = 2.2–31.3°
b = 5.0793 (6) Å	µ = 0.12 mm⁻¹
c = 24.500 (3) Å	T = 100 K
β = 100.202 (3)°	Block, yellow
V = 1143.6 (2) Å³	0.27 × 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 tube	3176 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.054
φ and ω scans	θ_max = 32.6°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −14→14
T_min = 0.968, T_max = 0.984	k = −7→7
27219 measured reflections	l = −36→37

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.118	All H-atom parameters refined
S = 1.03	w = 1/[σ²(F_o²) + (0.0568P)² + 0.2429P] where P = (F_o² + 2F_c²)/3
4135 reflections	(Δ/σ)_max < 0.001
204 parameters	Δρ_max = 0.39 e Å⁻³
0 restraints	Δρ_min = −0.23 e Å⁻³

Crystal data top

C₁₄H₈F₂N₂O	V = 1143.6 (2) Å³
M_r = 258.22	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 9.3377 (11) Å	µ = 0.12 mm⁻¹
b = 5.0793 (6) Å	T = 100 K
c = 24.500 (3) Å	0.27 × 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)
T_min = 0.968, T_max = 0.984	R_int = 0.054
27219 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.043	0 restraints
wR(F²) = 0.118	All H-atom parameters refined
S = 1.03	Δρ_max = 0.39 e Å⁻³
4135 reflections	Δρ_min = −0.23 e Å⁻³
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

	x	y	z	U_iso*/U_eq
F1	0.81277 (8)	0.06726 (14)	0.14252 (3)	0.03127 (18)
F2	1.02229 (7)	0.75952 (13)	0.05423 (3)	0.02670 (16)
O1	0.76102 (9)	0.12482 (15)	0.03141 (3)	0.02539 (18)
N1	0.75319 (9)	0.56187 (17)	0.01066 (3)	0.01774 (17)
N2	0.33842 (13)	0.5436 (2)	−0.24586 (5)	0.0384 (3)
C1	0.91364 (12)	0.2568 (2)	0.14216 (4)	0.0207 (2)
C2	1.01589 (13)	0.2889 (2)	0.18972 (5)	0.0252 (2)
C3	1.11850 (12)	0.4873 (2)	0.19138 (5)	0.0246 (2)
C4	1.11804 (11)	0.6494 (2)	0.14589 (5)	0.0228 (2)
C5	1.01538 (11)	0.6060 (2)	0.09898 (4)	0.01910 (19)
C6	0.90844 (10)	0.41080 (19)	0.09449 (4)	0.01688 (18)
C7	0.80070 (11)	0.35107 (19)	0.04285 (4)	0.01768 (19)
C8	0.66236 (11)	0.55108 (19)	−0.04175 (4)	0.01768 (19)
C9	0.67895 (12)	0.7489 (2)	−0.07969 (4)	0.0207 (2)
C10	0.59456 (12)	0.7492 (2)	−0.13217 (5)	0.0224 (2)
C11	0.49135 (11)	0.5511 (2)	−0.14682 (4)	0.0220 (2)
C12	0.47172 (12)	0.3569 (2)	−0.10873 (5)	0.0231 (2)
C13	0.55706 (11)	0.3555 (2)	−0.05623 (4)	0.0209 (2)
C14	0.40564 (13)	0.5474 (2)	−0.20187 (5)	0.0275 (2)
H1N1	0.7848 (16)	0.716 (3)	0.0216 (6)	0.031 (4)*
H2	1.0120 (16)	0.173 (3)	0.2194 (6)	0.031 (4)*
H3	1.1931 (16)	0.507 (3)	0.2249 (6)	0.031 (4)*
H4	1.1877 (17)	0.787 (3)	0.1456 (6)	0.028 (4)*
H9	0.7526 (15)	0.877 (3)	−0.0683 (6)	0.022 (3)*
H10	0.6115 (15)	0.879 (3)	−0.1573 (6)	0.026 (4)*
H12	0.3999 (17)	0.227 (3)	−0.1180 (6)	0.031 (4)*
H13	0.5408 (15)	0.221 (3)	−0.0309 (6)	0.026 (4)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
F1	0.0336 (4)	0.0283 (4)	0.0293 (4)	−0.0134 (3)	−0.0015 (3)	0.0072 (3)
F2	0.0242 (3)	0.0266 (3)	0.0274 (3)	−0.0063 (3)	−0.0006 (3)	0.0092 (3)
O1	0.0327 (4)	0.0133 (3)	0.0260 (4)	−0.0007 (3)	−0.0061 (3)	−0.0027 (3)
N1	0.0212 (4)	0.0123 (4)	0.0175 (4)	−0.0004 (3)	−0.0026 (3)	−0.0018 (3)
N2	0.0415 (6)	0.0392 (6)	0.0283 (5)	0.0086 (5)	−0.0108 (5)	−0.0071 (5)
C1	0.0227 (5)	0.0172 (5)	0.0215 (5)	−0.0029 (4)	0.0021 (4)	0.0004 (3)
C2	0.0283 (5)	0.0265 (5)	0.0195 (5)	−0.0012 (4)	0.0011 (4)	0.0017 (4)
C3	0.0235 (5)	0.0285 (6)	0.0198 (5)	−0.0004 (4)	−0.0018 (4)	−0.0042 (4)
C4	0.0190 (5)	0.0222 (5)	0.0257 (5)	−0.0025 (4)	−0.0003 (4)	−0.0029 (4)
C5	0.0187 (4)	0.0174 (4)	0.0206 (4)	0.0002 (3)	0.0020 (3)	0.0004 (3)
C6	0.0173 (4)	0.0145 (4)	0.0179 (4)	0.0004 (3)	0.0007 (3)	−0.0023 (3)
C7	0.0188 (4)	0.0144 (4)	0.0187 (4)	0.0009 (3)	0.0002 (3)	−0.0014 (3)
C8	0.0186 (4)	0.0156 (4)	0.0176 (4)	0.0020 (3)	−0.0003 (3)	−0.0030 (3)
C9	0.0240 (5)	0.0170 (4)	0.0194 (5)	−0.0008 (4)	−0.0007 (4)	−0.0015 (3)
C10	0.0264 (5)	0.0202 (5)	0.0189 (5)	0.0021 (4)	−0.0002 (4)	−0.0006 (4)
C11	0.0214 (5)	0.0226 (5)	0.0195 (5)	0.0049 (4)	−0.0037 (4)	−0.0055 (4)
C12	0.0196 (5)	0.0206 (5)	0.0266 (5)	−0.0003 (4)	−0.0030 (4)	−0.0051 (4)
C13	0.0206 (5)	0.0181 (5)	0.0224 (5)	−0.0004 (4)	−0.0008 (4)	−0.0012 (4)
C14	0.0279 (5)	0.0259 (5)	0.0254 (5)	0.0056 (4)	−0.0043 (4)	−0.0057 (4)

Geometric parameters (Å, º) top

F1—C1	1.3480 (12)	C4—H4	0.956 (15)
F2—C5	1.3563 (12)	C5—C6	1.3975 (14)
O1—C7	1.2246 (12)	C6—C7	1.5014 (13)
N1—C7	1.3569 (13)	C8—C9	1.3961 (14)
N1—C8	1.4091 (12)	C8—C13	1.3985 (14)
N1—H1N1	0.860 (16)	C9—C10	1.3839 (15)
N2—C14	1.1474 (15)	C9—H9	0.953 (14)
C1—C2	1.3791 (15)	C10—C11	1.3955 (15)
C1—C6	1.3992 (14)	C10—H10	0.933 (15)
C2—C3	1.3861 (16)	C11—C12	1.3922 (16)
C2—H2	0.943 (15)	C11—C14	1.4414 (15)
C3—C4	1.3849 (16)	C12—C13	1.3880 (15)
C3—H3	0.984 (15)	C12—H12	0.939 (15)
C4—C5	1.3777 (14)	C13—H13	0.952 (15)

C7—N1—C8	125.52 (8)	O1—C7—C6	120.86 (9)
C7—N1—H1N1	118.5 (10)	N1—C7—C6	115.57 (8)
C8—N1—H1N1	115.9 (10)	C9—C8—C13	119.89 (9)
F1—C1—C2	117.31 (9)	C9—C8—N1	117.32 (9)
F1—C1—C6	118.94 (9)	C13—C8—N1	122.78 (9)
C2—C1—C6	123.75 (10)	C10—C9—C8	120.48 (10)
C1—C2—C3	118.83 (10)	C10—C9—H9	122.3 (8)
C1—C2—H2	117.6 (9)	C8—C9—H9	117.2 (8)
C3—C2—H2	123.6 (9)	C9—C10—C11	119.47 (10)
C4—C3—C2	120.33 (10)	C9—C10—H10	118.6 (9)
C4—C3—H3	120.8 (9)	C11—C10—H10	121.9 (9)
C2—C3—H3	118.8 (9)	C12—C11—C10	120.36 (9)
C5—C4—C3	118.60 (10)	C12—C11—C14	120.06 (10)
C5—C4—H4	119.0 (9)	C10—C11—C14	119.58 (10)
C3—C4—H4	122.3 (9)	C13—C12—C11	120.18 (10)
F2—C5—C4	117.17 (9)	C13—C12—H12	119.3 (9)
F2—C5—C6	118.68 (9)	C11—C12—H12	120.5 (9)
C4—C5—C6	124.13 (10)	C12—C13—C8	119.60 (10)
C5—C6—C1	114.34 (9)	C12—C13—H13	118.5 (9)
C5—C6—C7	124.92 (9)	C8—C13—H13	121.9 (9)
C1—C6—C7	120.62 (9)	N2—C14—C11	179.41 (13)
O1—C7—N1	123.57 (9)

F1—C1—C2—C3	−178.04 (10)	C1—C6—C7—O1	−31.41 (15)
C6—C1—C2—C3	1.20 (18)	C5—C6—C7—N1	−35.04 (14)
C1—C2—C3—C4	−0.17 (18)	C1—C6—C7—N1	149.05 (10)
C2—C3—C4—C5	−1.07 (17)	C7—N1—C8—C9	−149.79 (11)
C3—C4—C5—F2	−176.83 (10)	C7—N1—C8—C13	31.27 (16)
C3—C4—C5—C6	1.43 (17)	C13—C8—C9—C10	−1.75 (16)
F2—C5—C6—C1	177.77 (9)	N1—C8—C9—C10	179.28 (10)
C4—C5—C6—C1	−0.47 (15)	C8—C9—C10—C11	0.62 (16)
F2—C5—C6—C7	1.63 (15)	C9—C10—C11—C12	0.98 (16)
C4—C5—C6—C7	−176.61 (10)	C9—C10—C11—C14	−178.58 (10)
F1—C1—C6—C5	178.35 (9)	C10—C11—C12—C13	−1.44 (16)
C2—C1—C6—C5	−0.88 (16)	C14—C11—C12—C13	178.11 (10)
F1—C1—C6—C7	−5.33 (15)	C11—C12—C13—C8	0.31 (16)
C2—C1—C6—C7	175.44 (10)	C9—C8—C13—C12	1.28 (16)
C8—N1—C7—O1	−5.34 (17)	N1—C8—C13—C12	−179.81 (10)
C8—N1—C7—C6	174.18 (9)	C7—O1—N1—H1N1	−1.4 (18)
C5—C6—C7—O1	144.50 (11)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	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.

Experimental details

Crystal data
Chemical formula	C₁₄H₈F₂N₂O
M_r	258.22
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	100
a, b, c (Å)	9.3377 (11), 5.0793 (6), 24.500 (3)
β (°)	100.202 (3)
V (Å³)	1143.6 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.12
Crystal size (mm)	0.27 × 0.14 × 0.14

Data collection
Diffractometer	Bruker APEXII DUO CCD area-detector
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.968, 0.984
No. of measured, independent and observed [I > 2σ(I)] reflections	27219, 4135, 3176
R_int	0.054
(sin θ/λ)_max (Å⁻¹)	0.758

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.043, 0.118, 1.03
No. of reflections	4135
No. of parameters	204
H-atom treatment	All H-atom parameters refined
Δρ_max, Δρ_min (e Å⁻³)	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···A	D—H	H···A	D···A	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.

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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