3-Fluoro-N-(3-fluoro­benzo­yl)-N-(2-pyrid­yl)benzamide

The title compound, C₁₉H₁₂F₂N₂O₂, a 2:1 product of the reaction of 3-fluoro­benzoyl­chloride and 2-amino­pyridine crystallizes with a disordered 3-fluoro­benzene ring adopting two conformations [ratio of occupancies 0.959 (4):0.041 (4)]. In the crystal structure, there are no classical hydrogen bonds and inter­actions comprise C—H...O in the form 2(C—H)...O=C [with motif R₂¹(5)]; C—H...π(arene) inter­actions are also present.

Key indicators

• Single-crystal X-ray study
• T = 150 K
• Mean [sigma](C-C) = 0.003 Å
• Disorder in main residue
• R factor = 0.057
• wR factor = 0.167
• Data-to-parameter ratio = 14.5

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT431_ALERT_2_A Short Inter HL..A Contact  F35    ..  F35     ..       2.40 Ang.

Author Response: The F35 site is a minor occupancy F site that is occupied by a H atom for 0.959(4) of unit occupancy and F35 for 0.041(4) of unit occupancy to total 1.00 unit occupancy. As the F site occupancy is < 0.5 (50%) a situation does not arise whereby two F atoms are actually 2.40 \%A from one another.

Alert level C
SHFSU01_ALERT_2_C  Test not performed. _refine_ls_shift/su_max and
            _refine_ls_shift/esd_max not present.
            Absolute value of the parameter shift to su ratio given   0.001
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.98
PLAT301_ALERT_3_C Main Residue  Disorder .........................       4.00 Perc.
PLAT366_ALERT_2_C Short? C(sp?)-C(sp?) Bond  C32    -   C33    ...       1.37 Ang.
PLAT366_ALERT_2_C Short? C(sp?)-C(sp?) Bond  C33    -   C34    ...       1.38 Ang.
PLAT224_ALERT_1_C Ueq(Rep) and Ueq(Calc) differ by  0.003 Ang   2 .        F35      

Alert level G
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          5

   1 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   6 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   4 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Our group is completing a structural systematic study of fluoro-N'-(pyridyl)benzamide isomers (Donnelly et al., 2008) and we are adding to our research with the analogous difluoro-N-(pyridyl)benzamide series (McMahon et al., 2008) (Scheme 1).

In the chemical synthesis of either the mono- or di-fluoro derivatives and when using the ortho-aminopyridine, two products can be isolated as either the 1:1 or 2:1 benzoyl:pyridine components, and with yields and ratios depending on the reaction conditions. We have reported the structure of the 1:1 derivative, 2,3-difluoro-N-(2-pyridyl)benzamide (Gallagher et al., 2008), and now report a 2:1 relative of this compound, namely 3-fluoro-N'-(3-fluorobenzoyl)-N'-(2-pyridinyl)benzamide (I) (Figs 1 & 2). The parent compound 2-(dibenzoylamino)pyridine has been reported previously (Weng et al., 2006) as well as the compounds N,N-dibenzoyl-4-chloroaniline and 4-acetyl-N,N-dibenzoylphenylamine (Usman et al., 2002a,b).

In the crystal structure of (I), there are no classical hydrogen bonds and the weaker interactions present consist of C—H···O and C—H···π(arene) contacts. An unusual (phenyl)C—H···C=O interaction arises between neighbouring molecules as (C24—H24/C25—H25)···O2=C2ⁱ [graph set R₂¹(5)] with O···C distances of 3.062 (3) and 3.097 (3) Å (symmetry code: i = x - 1, y + 1, z), Table 1.

A search of the literature (Allen, 2002) reveals a structure exhibiting a comparable example of hydrogen bonding and is archived in the CSD (as XOXRIL). However, in this structure the interacting molecules are offset with respect to the C=O···C₂ moiety in the aromatic C₅N ring. A related search yielded POZWUW (Fig. 3) (Moody et al., 1998) and RINXUI which both have relatively symmetrical C=O···C₂ distances similar to (I) and form chains along the b axis. In the POZWUW structure the C3/C4···O1ⁱⁱ distances are 3.013 (3) and 3.090 (3) Å, and similar to that in (I) (symmetry code: ii = x, y - 1, z) (Fig. 3).

A related search for C=O···C₂ [in C₆] yielded 6 compounds in the same range of C···O from 2.0–3.0 Å but most were disordered, with high R-factors and typically had the solvent benzene as the acceptor; these are listed as BARJUZ10, LAYDAQ, MERRIK, OGOPUV, SEDLET, XICFEV (Allen, 2002).

Related literature

For background information, see: Donnelly et al. (2008); Gallagher et al. (2008); McMahon et al. (2008); Moody et al. (1998). For a description of the Cambridge Structural Database, see: Allen (2002). For the parent compound, 2-(dibenzoylamino)pyridine, see: Weng et al. (2006). For related structures, see: Usman et al. (2002a,b).

S2. Experimental

Compound (I) was synthesized via standard condensation procedures and similar to the related syntheses reported previously (Donnelly et al., 2008; McMahon et al., 2008). Separation of the 1:1 and 2:1 derivatives was undertaken by using flash chromatography. Typical organic workup and washing gave the product (I) in modest yield of 25–35% as a 2:1 component of the mixture. Crystals suitable for X-ray diffraction were grown from CHCl₃ as colourless blocks over a period of 1–2 weeks and gave a melting point of 401–406 K. The compounds gave clean ¹H and ¹³C NMR spectra in CDC₃ and infrared spectra (in CHCl₃ solution, and as KBr disks).

For (I), m.p. 401–406 K (uncorrected). IR (ν_C=O cm^-1): 1697(s, br), (CHCl₃); 1695(s) (KBr).

S3. Refinement

Molecule (I) crystallized in the triclinic system; space group P1 (No. 2) assumed and confirmed by the refinement and analysis. In the final stages of refinement it was observed that there was electron density consistent with a partial occupancy F atom in a position expected for a minor orientation (site) of the F33 atom position. This new site only necessitates rotation by 180° about the C2—C31 axis in a group that is not engaged in strong hydrogen bonding.

The minor F35 site was treated initially with isotropic displacement values and in the final refinement cycles was restrained by DFIX values to 1.350 (5) Å, SIMU restraints of 0.2 (F33, F35) and FLAT constraints of 0.1 with the {C31···C36} benzene ring. The final refinement gave site occupancy values of 0.959 (4):0.041 (4). As the major and minor sites for the C₆ ring are essentially coincidental it was decided to retain the major orientation with 100% occupancy for use with the restraints.

Refinement and disorder analysis: (WGHT, R-factor and residual electron density).

Refinement without disorder gives an R-factor of 0.058 WGHT = 0.0856 0.018, R = 0.058 and +0.40/-0.30. Refinement with F33 at variable occupancy changes site from 1.000 to 0.937. WGHT = 0.082 0.018, R = 0.057 and +0.39/-0.30. Final refinement and treatment of disorder gives an R-factor of 0.057: WGHT = 0.0816 0, R = 0.057 and +0.26/-0.32 [Inclusion of the minor site at F35 using DFIX/SIMU/FLAT restraints].

H atoms attached to C atoms were treated as riding with C—H = 0.95 Å, and with U_iso(H) = 1.2U_eq(C).

Computing details

Data collection: KappaCCD Server Software (Nonius, 1997); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) and SORTX (McArdle, 1995); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PREP8 (Ferguson, 1998).

Figures

	Fig. 1. A view of (I) with the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. The disordered F33/F35 sites are depicted for clarity.
	Fig. 2. A view of the C—H···O interactions in the crystal structure of (I).
	Fig. 3. A view of the 2x(C—H)···O=C interaction in POZWUW crystal structure with atoms drawn as their van der Waals spheres (Moody et al., 1998).
	Fig. 4. The CSD instructions and search criteria for the 2x(C—H)···O=C interaction in related structures.

3-Fluoro-N-(3-fluorobenzoyl)-N-(2-pyridyl)benzamide

Crystal data

C19H12F2N2O2	Z = 2
Mr = 338.31	F(000) = 348
Triclinic, P1	Dx = 1.471 Mg m^−3
Hall symbol: -P 1	Melting point: 403 K
a = 5.4932 (4) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.1549 (5) Å	Cell parameters from 2910 reflections
c = 17.9205 (15) Å	θ = 2.6–27.5°
α = 78.081 (4)°	µ = 0.11 mm^−1
β = 89.588 (3)°	T = 150 K
γ = 76.693 (3)°	Block, colourless
V = 763.69 (10) Å^3	0.34 × 0.30 × 0.12 mm

Data collection

Nonius KappaCCD diffractometer	3422 independent reflections
Radiation source: fine-focus sealed X-ray tube	1966 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.043
ϕ, and ω scans with κ offsets	θmax = 27.5°, θmin = 2.6°
Absorption correction: multi-scan (SORTAV; Blessing, 1995)	h = −7→7
Tmin = 0.873, Tmax = 0.992	k = −10→10
5197 measured reflections	l = −20→23

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.057	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.167	H-atom parameters constrained
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0816P)^2] where P = (Fo^2 + 2Fc^2)/3
3422 reflections	(Δ/σ)max < 0.001
236 parameters	Δρmax = 0.26 e Å^−3
5 restraints	Δρmin = −0.32 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
F13	1.4634 (3)	0.23528 (17)	0.51411 (9)	0.0438 (4)
F33	0.7405 (3)	0.6582 (2)	−0.04453 (9)	0.0534 (6)	0.959 (4)
F35	0.085 (3)	0.975 (3)	0.064 (3)	0.072 (17)	0.041 (4)
O1	1.0215 (3)	0.83326 (19)	0.37748 (10)	0.0389 (5)
C1	0.9639 (4)	0.7323 (3)	0.34430 (14)	0.0268 (6)
C11	1.0136 (4)	0.5439 (3)	0.37798 (13)	0.0247 (5)
C12	1.2170 (4)	0.4755 (3)	0.42993 (14)	0.0283 (6)
C13	1.2672 (4)	0.3023 (3)	0.46246 (14)	0.0302 (6)
C14	1.1272 (5)	0.1930 (3)	0.44586 (14)	0.0316 (6)
C15	0.9220 (5)	0.2637 (3)	0.39557 (14)	0.0310 (6)
C16	0.8640 (4)	0.4374 (3)	0.36223 (14)	0.0285 (6)
N1	0.8296 (4)	0.7932 (2)	0.27278 (11)	0.0252 (5)
C21	0.7380 (4)	0.9785 (3)	0.25150 (13)	0.0232 (5)
N22	0.8718 (4)	1.0596 (2)	0.20067 (11)	0.0282 (5)
C23	0.7874 (4)	1.2313 (3)	0.17910 (14)	0.0293 (6)
C24	0.5739 (4)	1.3220 (3)	0.20586 (14)	0.0288 (6)
C25	0.4409 (4)	1.2343 (3)	0.25976 (14)	0.0282 (6)
C26	0.5261 (4)	1.0580 (3)	0.28380 (14)	0.0279 (6)
O2	1.0823 (3)	0.5907 (2)	0.21749 (10)	0.0357 (5)
C2	0.8926 (4)	0.7035 (3)	0.21272 (13)	0.0259 (5)
C31	0.7138 (4)	0.7490 (3)	0.14525 (13)	0.0256 (5)
C32	0.8076 (5)	0.6859 (3)	0.08106 (14)	0.0287 (6)
C33	0.6501 (5)	0.7166 (3)	0.01795 (15)	0.0361 (6)
C34	0.4039 (5)	0.8066 (3)	0.01530 (16)	0.0381 (7)
C35	0.3124 (5)	0.8666 (3)	0.07875 (15)	0.0345 (6)
C36	0.4653 (4)	0.8371 (3)	0.14401 (14)	0.0279 (6)
H12	1.3185	0.5466	0.4426	0.034*
H14	1.1701	0.0733	0.4682	0.038*
H15	0.8200	0.1921	0.3838	0.037*
H16	0.7212	0.4844	0.3284	0.034*
H23	0.8801	1.2933	0.1435	0.035*
H24	0.5183	1.4429	0.1877	0.035*
H25	0.2943	1.2942	0.2797	0.034*
H26	0.4418	0.9937	0.3213	0.033*
H32	0.9764	0.6232	0.0812	0.034*
H33	0.7134	0.6742	−0.0256	0.043*	0.041 (4)
H34	0.2998	0.8267	−0.0293	0.046*
H35	0.1431	0.9288	0.0780	0.041*	0.959 (4)
H36	0.3993	0.8775	0.1878	0.034*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
F13	0.0402 (9)	0.0387 (8)	0.0439 (10)	−0.0050 (7)	−0.0157 (8)	0.0068 (7)
F33	0.0543 (12)	0.0759 (13)	0.0333 (11)	−0.0060 (9)	0.0036 (8)	−0.0295 (9)
F35	0.07 (3)	0.06 (3)	0.07 (4)	−0.02 (3)	−0.02 (3)	0.01 (2)
O1	0.0534 (12)	0.0265 (9)	0.0372 (11)	−0.0090 (9)	−0.0134 (9)	−0.0078 (8)
C1	0.0250 (13)	0.0276 (12)	0.0256 (14)	−0.0026 (11)	−0.0028 (10)	−0.0049 (11)
C11	0.0268 (13)	0.0234 (11)	0.0226 (13)	−0.0030 (10)	0.0023 (10)	−0.0054 (10)
C12	0.0295 (13)	0.0268 (12)	0.0292 (14)	−0.0068 (11)	−0.0019 (11)	−0.0074 (11)
C13	0.0266 (13)	0.0286 (13)	0.0302 (15)	−0.0014 (10)	−0.0038 (11)	0.0000 (11)
C14	0.0370 (15)	0.0238 (12)	0.0309 (15)	−0.0054 (11)	0.0038 (12)	−0.0008 (11)
C15	0.0361 (14)	0.0275 (13)	0.0309 (15)	−0.0112 (11)	0.0012 (12)	−0.0052 (11)
C16	0.0291 (13)	0.0313 (13)	0.0248 (14)	−0.0048 (11)	−0.0019 (11)	−0.0072 (11)
N1	0.0300 (11)	0.0192 (9)	0.0245 (11)	−0.0015 (8)	−0.0025 (9)	−0.0045 (8)
C21	0.0257 (13)	0.0181 (11)	0.0240 (13)	−0.0001 (10)	−0.0039 (10)	−0.0056 (9)
N22	0.0295 (11)	0.0240 (10)	0.0310 (12)	−0.0053 (9)	0.0021 (9)	−0.0064 (9)
C23	0.0322 (14)	0.0247 (12)	0.0308 (15)	−0.0083 (11)	0.0012 (11)	−0.0033 (11)
C24	0.0338 (14)	0.0187 (11)	0.0318 (15)	−0.0026 (10)	−0.0039 (11)	−0.0046 (10)
C25	0.0304 (13)	0.0245 (12)	0.0292 (14)	−0.0027 (10)	−0.0001 (11)	−0.0086 (10)
C26	0.0302 (13)	0.0271 (12)	0.0267 (14)	−0.0074 (11)	0.0031 (11)	−0.0057 (10)
O2	0.0382 (10)	0.0295 (9)	0.0310 (11)	0.0069 (8)	0.0042 (8)	−0.0038 (8)
C2	0.0322 (14)	0.0182 (11)	0.0261 (14)	−0.0032 (10)	0.0054 (11)	−0.0050 (10)
C31	0.0322 (13)	0.0203 (11)	0.0250 (14)	−0.0082 (10)	0.0020 (11)	−0.0044 (10)
C32	0.0302 (13)	0.0240 (12)	0.0318 (15)	−0.0063 (11)	0.0036 (11)	−0.0058 (11)
C33	0.0456 (17)	0.0386 (14)	0.0284 (15)	−0.0139 (13)	0.0076 (13)	−0.0127 (12)
C34	0.0413 (16)	0.0445 (15)	0.0321 (16)	−0.0144 (13)	−0.0033 (13)	−0.0111 (13)
C35	0.0316 (14)	0.0329 (14)	0.0400 (17)	−0.0085 (12)	−0.0006 (12)	−0.0090 (12)
C36	0.0306 (14)	0.0257 (12)	0.0299 (15)	−0.0082 (11)	0.0024 (11)	−0.0092 (11)

Geometric parameters (Å, º)

F13—C13	1.361 (3)	C25—C26	1.381 (3)
F33—C33	1.353 (3)	C31—C32	1.402 (3)
F35—C35	1.347 (5)	C31—C36	1.387 (3)
O1—C1	1.207 (2)	C32—C33	1.374 (3)
C1—N1	1.420 (3)	C33—C34	1.378 (4)
O2—C2	1.211 (3)	C34—C35	1.376 (4)
C2—C31	1.493 (3)	C35—C36	1.391 (3)
N1—C2	1.420 (3)	C12—H12	0.9500
N1—C21	1.448 (3)	C14—H14	0.9500
C1—C11	1.492 (3)	C15—H15	0.9500
C11—C12	1.393 (3)	C16—H16	0.9500
C11—C16	1.394 (3)	C23—H23	0.9500
C12—C13	1.377 (3)	C24—H24	0.9500
C13—C14	1.379 (3)	C25—H25	0.9500
C14—C15	1.384 (3)	C26—H26	0.9500
C15—C16	1.382 (3)	C32—H32	0.9500
C21—N22	1.331 (3)	C33—H33	0.9500
C21—C26	1.382 (3)	C34—H34	0.9500
N22—C23	1.344 (3)	C35—H35	0.9500
C23—C24	1.375 (3)	C36—H36	0.9500
C24—C25	1.387 (3)
O1—C1—N1	119.86 (19)	C32—C33—C34	122.6 (2)
O1—C1—C11	122.3 (2)	C35—C34—C33	118.5 (2)
N1—C1—C11	117.67 (18)	C34—C35—C36	120.7 (2)
C12—C11—C16	119.5 (2)	C31—C36—C35	120.1 (2)
C12—C11—C1	116.76 (18)	C13—C12—H12	120.9
C16—C11—C1	123.7 (2)	C11—C12—H12	120.9
C13—C12—C11	118.3 (2)	C13—C14—H14	121.1
F13—C13—C12	118.5 (2)	C15—C14—H14	121.1
F13—C13—C14	118.2 (2)	C16—C15—H15	119.6
C12—C13—C14	123.3 (2)	C14—C15—H15	119.6
C13—C14—C15	117.7 (2)	C15—C16—H16	119.8
C16—C15—C14	120.7 (2)	C11—C16—H16	119.8
C15—C16—C11	120.4 (2)	N22—C23—H23	118.3
C1—N1—C2	120.05 (18)	C24—C23—H23	118.3
C1—N1—C21	114.85 (17)	C23—C24—H24	120.5
C2—N1—C21	117.18 (18)	C25—C24—H24	120.5
N22—C21—C26	124.97 (19)	C26—C25—H25	120.7
N22—C21—N1	115.2 (2)	C24—C25—H25	120.7
C26—C21—N1	119.8 (2)	C25—C26—H26	121.1
C21—N22—C23	116.2 (2)	C21—C26—H26	121.1
N22—C23—C24	123.4 (2)	C33—C32—H32	120.7
C23—C24—C25	119.0 (2)	C31—C32—H32	120.7
C26—C25—C24	118.6 (2)	C32—C33—H33	118.7
C25—C26—C21	117.7 (2)	C34—C33—H33	118.7
O2—C2—N1	120.7 (2)	C35—C34—H34	120.8
O2—C2—C31	121.5 (2)	C33—C34—H34	120.8
N1—C2—C31	117.8 (2)	C34—C35—H35	119.7
C36—C31—C32	119.5 (2)	C36—C35—H35	119.7
C36—C31—C2	124.9 (2)	C31—C36—H36	119.9
C32—C31—C2	115.4 (2)	C35—C36—H36	119.9
C33—C32—C31	118.6 (2)
O1—C1—C11—C12	−27.9 (3)	N1—C21—N22—C23	178.84 (18)
N1—C1—C11—C12	156.2 (2)	C21—N22—C23—C24	−1.0 (3)
O1—C1—C11—C16	149.8 (2)	N22—C23—C24—C25	2.1 (3)
N1—C1—C11—C16	−26.1 (3)	C23—C24—C25—C26	−1.0 (3)
C16—C11—C12—C13	1.8 (4)	C24—C25—C26—C21	−1.1 (3)
C1—C11—C12—C13	179.6 (2)	N22—C21—C26—C25	2.3 (3)
C11—C12—C13—F13	−179.0 (2)	N1—C21—C26—C25	−177.79 (18)
C11—C12—C13—C14	0.4 (4)	C1—N1—C2—O2	−11.0 (3)
F13—C13—C14—C15	177.5 (2)	C21—N1—C2—O2	136.5 (2)
C12—C13—C14—C15	−2.0 (4)	C1—N1—C2—C31	167.05 (19)
C13—C14—C15—C16	1.3 (4)	C21—N1—C2—C31	−45.5 (3)
C14—C15—C16—C11	0.9 (4)	O2—C2—C31—C36	160.4 (2)
C12—C11—C16—C15	−2.5 (4)	N1—C2—C31—C36	−17.6 (3)
C1—C11—C16—C15	179.9 (2)	O2—C2—C31—C32	−15.4 (3)
O1—C1—N1—C2	138.7 (2)	N1—C2—C31—C32	166.55 (19)
C11—C1—N1—C2	−45.3 (3)	C36—C31—C32—C33	1.3 (3)
O1—C1—N1—C21	−9.4 (3)	C2—C31—C32—C33	177.3 (2)
C11—C1—N1—C21	166.5 (2)	C31—C32—C33—C34	−0.1 (3)
C1—N1—C21—N22	101.8 (2)	C32—C33—C34—C35	−0.5 (4)
C2—N1—C21—N22	−47.3 (3)	C33—C34—C35—C36	0.1 (4)
C1—N1—C21—C26	−78.1 (3)	C32—C31—C36—C35	−1.7 (3)
C2—N1—C21—C26	132.8 (2)	C2—C31—C36—C35	−177.4 (2)
C26—C21—N22—C23	−1.3 (3)	C34—C35—C36—C31	1.1 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C24—H24···O2^i	0.95	2.53	3.097 (3)	119
C25—H25···O2^i	0.95	2.46	3.063 (3)	121
C25—H25···Cg1^i	0.95	2.79	3.606 (3)	145

Symmetry code: (i) x−1, y+1, z.