2,6-Di­bromo-4-fluoro­benzo­nitrile

The title compound, C₇H₂Br₂FN, packs in approximately planar sheets with mol­ecules held together in pairs by CN...Br intermolecular Lewis acid–base interactions across a center of symmetry. The CN...Br arrangement is approximately linear at the Br atom and bent at the N atom, with an N...Br distance of 3.11 Å. The molecular pairs form sheets through C—H...N hydrogen bonds, with H...N distances of 2.55 Å, and C—H...F hydrogen bonds with H...F distances of 2.68 Å.

Key indicators

• Single-crystal X-ray study
• T = 123 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.036
• wR factor = 0.089
• Data-to-parameter ratio = 17.9

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level C:



PLAT_371  Alert C Long   C(sp2)-C(sp1) Bond  C(1)   -   C(7)   =       1.43 Ang.


 0 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 1 Alert Level C = Please check

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Computing details

Data collection: SMART (Siemens, 1995); cell refinement: SAINT (Siemens, 1995); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 1994); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

2,6-dibromo-4-fluorobenzonitrile

Crystal data

C7H2Br2FN	Dx = 2.357 Mg m^−3
Mr = 278.92	Melting point = 376–377 K
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 4.0352 (10) Å	Cell parameters from 904 reflections
b = 17.710 (4) Å	θ = 3.0–27.4°
c = 11.007 (3) Å	µ = 10.26 mm^−1
β = 92.31 (1)°	T = 123 K
V = 785.9 (3) Å^3	Prism, yellow
Z = 4	0.20 × 0.15 × 0.05 mm
F(000) = 520

Data collection

Siemens SMART area-detector diffractometer	1792 independent reflections
Radiation source: fine-focus sealed tube	1325 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.059
ω scans	θmax = 27.5°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996; Blessing, 1995)	h = −5→5
Tmin = 0.17, Tmax = 0.60	k = −22→23
6999 measured reflections	l = −14→13

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)] = 0.036	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.089	H-atom parameters constrained
S = 0.95	w = 1/[σ^2(Fo^2) + (0.052P)^2] where P = (Fo^2 + 2Fc^2)/3
1792 reflections	(Δ/σ)max = 0.001
100 parameters	Δρmax = 0.68 e Å^−3
0 restraints	Δρmin = −0.94 e Å^−3

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

	x	y	z	Uiso*/Ueq
Br2	0.19663 (13)	0.20895 (2)	0.26495 (5)	0.04662 (17)
Br6	0.22614 (11)	0.52566 (2)	0.34081 (4)	0.03740 (15)
F4	−0.3834 (7)	0.40000 (16)	−0.0274 (2)	0.0528 (7)
N1	0.5514 (10)	0.3470 (2)	0.4791 (3)	0.0453 (9)
C1	0.1826 (10)	0.3688 (2)	0.2866 (3)	0.0307 (9)
C2	0.0749 (11)	0.3070 (2)	0.2140 (4)	0.0333 (9)
C3	−0.1138 (11)	0.3167 (2)	0.1085 (4)	0.0368 (10)
H3	−0.1829	0.2749	0.0598	0.044*
C4	−0.1980 (11)	0.3889 (2)	0.0764 (4)	0.0357 (9)
C5	−0.1029 (11)	0.4518 (2)	0.1418 (4)	0.0355 (9)
H5	−0.1655	0.5010	0.1152	0.043*
C6	0.0874 (10)	0.4411 (2)	0.2477 (4)	0.0311 (9)
C7	0.3807 (12)	0.3574 (2)	0.3957 (4)	0.0382 (10)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br2	0.0578 (3)	0.0242 (2)	0.0580 (3)	−0.00121 (19)	0.0036 (2)	0.00006 (19)
Br6	0.0474 (3)	0.0259 (2)	0.0385 (3)	−0.00074 (17)	−0.00304 (19)	−0.00438 (17)
F4	0.065 (2)	0.0554 (17)	0.0369 (14)	−0.0052 (14)	−0.0157 (14)	−0.0012 (12)
N1	0.050 (3)	0.042 (2)	0.043 (2)	0.0022 (19)	−0.008 (2)	0.0056 (18)
C1	0.037 (2)	0.0276 (19)	0.028 (2)	−0.0001 (16)	0.0028 (17)	0.0000 (16)
C2	0.036 (2)	0.030 (2)	0.034 (2)	−0.0013 (17)	0.0045 (19)	0.0031 (17)
C3	0.041 (3)	0.034 (2)	0.035 (2)	−0.0092 (19)	0.003 (2)	−0.0072 (18)
C4	0.035 (2)	0.043 (2)	0.028 (2)	−0.0062 (19)	−0.0033 (18)	0.0007 (18)
C5	0.039 (2)	0.035 (2)	0.033 (2)	0.0000 (18)	0.0021 (19)	0.0046 (18)
C6	0.035 (2)	0.0277 (19)	0.031 (2)	−0.0054 (17)	0.0011 (18)	−0.0004 (17)
C7	0.041 (3)	0.032 (2)	0.041 (3)	0.0010 (19)	0.002 (2)	0.0003 (19)

Geometric parameters (Å, º)

Br2—C2	1.884 (4)	C2—C3	1.373 (6)
Br6—C6	1.887 (4)	C3—C4	1.366 (6)
F4—C4	1.355 (5)	C3—H3	0.9500
N1—C7	1.140 (6)	C4—C5	1.371 (6)
C1—C6	1.398 (5)	C5—C6	1.384 (6)
C1—C2	1.412 (6)	C5—H5	0.9500
C1—C7	1.430 (6)
C6—C1—C2	117.5 (4)	F4—C4—C5	117.3 (4)
C6—C1—C7	121.5 (4)	C3—C4—C5	124.2 (4)
C2—C1—C7	121.0 (4)	C4—C5—C6	117.7 (4)
C3—C2—C1	121.9 (4)	C4—C5—H5	121.1
C3—C2—Br2	119.7 (3)	C6—C5—H5	121.1
C1—C2—Br2	118.4 (3)	C5—C6—C1	121.3 (4)
C4—C3—C2	117.4 (4)	C5—C6—Br6	119.4 (3)
C4—C3—H3	121.3	C1—C6—Br6	119.3 (3)
C2—C3—H3	121.3	N1—C7—C1	176.5 (5)
F4—C4—C3	118.5 (4)