N,N'-Bis(4-bromo-2-fluoro-benzyl-idene)ethane-1,2-diamine.

The mol-ecule of the title Schiff base compound, C(16)H(12)Br(2)F(2)N(2), lies across a crystallographic inversion centre and adopts an E configuration with respect to the azomethine C=N bonds. The imino groups are coplanar with the aromatic rings. Within the mol-ecule, the planar units are parallel, but extend in opposite directions from the dimethyl-ene bridge. An inter-esting feature of the crystal structure is the short inter-molecular Br⋯F inter-actions [3.2347 (16) Å, which is shorter than the sum of the van der Waals radii of these atoms]. These inter-actions link neighbouring mol-ecules along the c axis. The crystal structure is further stabilized by inter-molecular C-H⋯N hydrogen bonds.

Related literature

For bond-length data, see: Allen et al. (1987 ▶). For halogen–halogen inter­actions, see: Ramasubbu et al. (1986 ▶); Brammer et al. (2003 ▶). For related structures, see, for example: Fun & Kia (2008a ▶,b ▶,c ▶): Fun et al. (2008 ▶). For Schiff base complexes and their applications, see, for example: Pal et al. (2005 ▶); Calligaris & Randaccio, (1987 ▶); Hou et al. (2001 ▶); Ren et al. (2002 ▶).

Experimental

Crystal data

C16H12Br2F2N2

M = 430.10

Monoclinic,

a = 4.1981 (1) Å

b = 14.6190 (3) Å

c = 12.8861 (3) Å

β = 104.751 (2)°

V = 764.78 (3) Å3

Z = 2

Mo Kα radiation

μ = 5.32 mm−1

T = 100.0 (1) K

0.51 × 0.07 × 0.05 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T min = 0.172, T max = 0.769

19361 measured reflections

2631 independent reflections

1907 reflections with I > 2σ(I)

R int = 0.050

Refinement

R[F 2 > 2σ(F 2)] = 0.040

wR(F 2) = 0.100

S = 1.05

2631 reflections

100 parameters

H-atom parameters constrained

Δρmax = 1.40 e Å−3

Δρmin = −0.85 e Å−3

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: APEX2; data reduction: SAINT (Bruker, 2005 ▶); 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, 2003 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808029000/at2629sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808029000/at2629Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C16H12Br2F2N2	F(000) = 420
Mr = 430.10	Dx = 1.868 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 5643 reflections
a = 4.1981 (1) Å	θ = 3.2–30.0°
b = 14.6190 (3) Å	µ = 5.32 mm−1
c = 12.8861 (3) Å	T = 100 K
β = 104.751 (2)°	Needle, colourless
V = 764.78 (3) Å3	0.51 × 0.07 × 0.05 mm
Z = 2

Bruker SMART APEXII CCD area-detector diffractometer	2631 independent reflections
Radiation source: fine-focus sealed tube	1907 reflections with I > 2σ(I)
graphite	Rint = 0.050
φ and ω scans	θmax = 32.0°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −6→6
Tmin = 0.172, Tmax = 0.770	k = −21→21
19361 measured reflections	l = −19→18

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)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.100	H-atom parameters constrained
S = 1.05	w = 1/[σ2(Fo2) + (0.0539P)2] where P = (Fo2 + 2Fc2)/3
2631 reflections	(Δ/σ)max < 0.001
100 parameters	Δρmax = 1.40 e Å−3
0 restraints	Δρmin = −0.86 e Å−3

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'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 > σ(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.

	x	y	z	Uiso*/Ueq
Br1	−0.74079 (7)	−0.51485 (2)	0.18481 (2)	0.02329 (11)
F1	−0.0347 (4)	−0.22639 (11)	0.31348 (12)	0.0267 (4)
N1	−0.0960 (6)	−0.12204 (15)	0.01873 (19)	0.0192 (5)
C1	−0.2112 (7)	−0.27577 (19)	0.2280 (2)	0.0199 (5)
C2	−0.3675 (7)	−0.35336 (19)	0.2493 (2)	0.0206 (6)
H2A	−0.3576	−0.3716	0.3192	0.025*
C3	−0.5404 (7)	−0.40314 (18)	0.1619 (2)	0.0181 (5)
C4	−0.5632 (7)	−0.37558 (19)	0.0569 (2)	0.0215 (6)
H4A	−0.6819	−0.4099	−0.0009	0.026*
C5	−0.4047 (7)	−0.29567 (19)	0.0405 (2)	0.0208 (6)
H5A	−0.4212	−0.2761	−0.0293	0.025*
C6	−0.2210 (6)	−0.24370 (18)	0.1260 (2)	0.0174 (5)
C7	−0.0381 (6)	−0.16150 (18)	0.1090 (2)	0.0182 (5)
H7A	0.1239	−0.1380	0.1659	0.022*
C8	0.1076 (7)	−0.04254 (19)	0.0114 (2)	0.0208 (5)
H8A	0.2171	−0.0516	−0.0456	0.025*
H8B	0.2750	−0.0349	0.0783	0.025*

	U11	U22	U33	U12	U13	U23
Br1	0.02442 (16)	0.01848 (15)	0.02622 (17)	−0.00289 (11)	0.00507 (11)	0.00316 (11)
F1	0.0383 (10)	0.0214 (9)	0.0173 (8)	−0.0032 (7)	0.0014 (7)	−0.0029 (6)
N1	0.0213 (11)	0.0165 (11)	0.0209 (11)	−0.0001 (9)	0.0072 (9)	0.0004 (9)
C1	0.0220 (13)	0.0195 (14)	0.0163 (12)	0.0024 (10)	0.0015 (10)	−0.0035 (10)
C2	0.0261 (14)	0.0187 (13)	0.0168 (13)	0.0035 (10)	0.0051 (11)	0.0018 (10)
C3	0.0191 (12)	0.0153 (12)	0.0209 (13)	−0.0006 (9)	0.0066 (10)	0.0012 (10)
C4	0.0221 (13)	0.0231 (14)	0.0187 (13)	−0.0001 (11)	0.0042 (11)	−0.0006 (11)
C5	0.0231 (13)	0.0197 (13)	0.0185 (13)	0.0003 (10)	0.0034 (11)	0.0022 (10)
C6	0.0192 (13)	0.0142 (12)	0.0196 (13)	0.0031 (9)	0.0064 (10)	0.0015 (10)
C7	0.0182 (12)	0.0151 (12)	0.0210 (13)	0.0016 (9)	0.0042 (10)	−0.0022 (10)
C8	0.0178 (12)	0.0194 (12)	0.0251 (14)	−0.0027 (10)	0.0055 (10)	−0.0026 (11)

Br1—C3	1.895 (3)	C4—C5	1.387 (4)
F1—C1	1.366 (3)	C4—H4A	0.9300
N1—C7	1.265 (3)	C5—C6	1.398 (4)
N1—C8	1.460 (4)	C5—H5A	0.9300
C1—C2	1.373 (4)	C6—C7	1.472 (4)
C1—C6	1.387 (4)	C7—H7A	0.9300
C2—C3	1.382 (4)	C8—C8i	1.521 (6)
C2—H2A	0.9300	C8—H8A	0.9700
C3—C4	1.391 (4)	C8—H8B	0.9700
C7—N1—C8	116.3 (2)	C4—C5—H5A	119.1
F1—C1—C2	117.7 (2)	C6—C5—H5A	119.1
F1—C1—C6	117.7 (2)	C1—C6—C5	116.2 (2)
C2—C1—C6	124.6 (3)	C1—C6—C7	121.8 (2)
C1—C2—C3	116.8 (3)	C5—C6—C7	122.0 (2)
C1—C2—H2A	121.6	N1—C7—C6	121.6 (2)
C3—C2—H2A	121.6	N1—C7—H7A	119.2
C2—C3—C4	122.2 (2)	C6—C7—H7A	119.2
C2—C3—Br1	119.2 (2)	N1—C8—C8i	109.6 (3)
C4—C3—Br1	118.6 (2)	N1—C8—H8A	109.8
C5—C4—C3	118.4 (3)	C8i—C8—H8A	109.8
C5—C4—H4A	120.8	N1—C8—H8B	109.8
C3—C4—H4A	120.8	C8i—C8—H8B	109.8
C4—C5—C6	121.9 (3)	H8A—C8—H8B	108.2
F1—C1—C2—C3	−179.0 (2)	F1—C1—C6—C7	2.4 (4)
C6—C1—C2—C3	1.3 (4)	C2—C1—C6—C7	−177.9 (3)
C1—C2—C3—C4	−1.5 (4)	C4—C5—C6—C1	−1.1 (4)
C1—C2—C3—Br1	176.3 (2)	C4—C5—C6—C7	176.7 (3)
C2—C3—C4—C5	0.4 (4)	C8—N1—C7—C6	−178.5 (2)
Br1—C3—C4—C5	−177.4 (2)	C1—C6—C7—N1	−165.9 (3)
C3—C4—C5—C6	1.0 (4)	C5—C6—C7—N1	16.4 (4)
F1—C1—C6—C5	−179.8 (2)	C7—N1—C8—C8i	−115.8 (3)
C2—C1—C6—C5	−0.1 (4)

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2A···N1ii	0.93	2.53	3.386 (3)	154.

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2A⋯N1i	0.93	2.53	3.386 (3)	154

Symmetry code: (i) .