4-Bromo-2-chloro­aniline

Abstract

The title compound, C₆H₅BrClN, is almost planar (r.m.s. deviation = 0.018 Å). In the crystal, mol­ecules are linked by inter­molecular N—H⋯N and weak N—H⋯Br hydrogen bonds, generating sheets.

Related literature

For background to halogentaed aromatic compounds, see: Katritzky et al. (1994 ▶). For related structures, see: Cox (2001 ▶); Parkin et al. (2005 ▶); Ng (2005 ▶); Ferguson et al. (1998 ▶). For the synthesis, see: Ault & Kraig (1966 ▶).

Experimental

Crystal data

• C₆H₅BrClN

• M _r = 206.47

• Orthorhombic,

• a = 10.965 (4) Å

• b = 15.814 (6) Å

• c = 4.0232 (15) Å

• V = 697.7 (4) ų

• Z = 4

• Mo Kα radiation

• μ = 6.17 mm⁻¹

• T = 298 K

• 0.7 × 0.19 × 0.15 mm

Data collection

• Bruker SMART CCD diffractometer

• Absorption correction: multi-scan (SADABS; Bruker, 2001 ▶) T _min = 0.254, T _max = 0.396

• 5799 measured reflections

• 1710 independent reflections

• 1333 reflections with I > 2σ(I)

• R _int = 0.044

Refinement

• R[F ² > 2σ(F ²)] = 0.033

• wR(F ²) = 0.081

• S = 0.99

• 1710 reflections

• 83 parameters

• H-atom parameters constrained

• Δρ_max = 0.33 e Å⁻³

• Δρ_min = −0.48 e Å⁻³

• Absolute structure: Flack (1983 ▶), 511 Friedel pairs

• Flack parameter: 0.035 (15)

Data collection: SMART (Bruker, 2001 ▶); cell refinement: SAINT (Bruker, 2001 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: ORTEP-3 (Farrugia, 1997 ▶); software used to prepare material for publication: SHELXTL.

Supplementary Material

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

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1B⋯Br1i	0.86	3.04	3.719 (3)	137
N1—H1A⋯N1ii	0.86	2.34	3.172 (4)	164

Symmetry codes: (i) ; (ii) .

supplementary crystallographic information

Comment

Halogenated aromatic compounds is an important class of intermediates for the synthesis of bio-active substances such as antibacterial, antioxidizing, antiviral agents (e.g. Katritzky et al., 1994). Despite their simple structures, the X-ray structures of halogenated aniline compounds periodically were reported, such as 2,5-dichloroaniline (Cox, 2001), 2-iodoaniline (Parkin et al., 2005) and 5-chloro-2-nitroaniline (Ng, 2005). We now report the title compound, (I).

The packing of molecules in the crystal structure is stabilized and linked into a two-dimensional texture by intermolecular N—H···N and N—H···Br hydrogen bonds. The N···N distance is 3.172 (4) Å in hydrogen bond N—H···N, which are similar to that observed in 2,4-dibromo-6- chloroaniline (Ferguson et al., 1998), 3.150 (11) Å and 2-iodoaniline (Parkin et al., 2005), 3.161 (14) Å.

Experimental

The tiltle compound was prepared according to a previously reported method (Ault & Kraig, 1966). Colourless needles of (I) were obtained by slow evaporation of a petroleum ether solution.

Refinement

The hydrogen atoms were positioned geometrically, with C—H = 0.93, 0.98, 0.97 and 0.96 Å for phenyl, methine, methylene and methyl H atoms, respectively, and were included in the refinement in the riding model approximation. The displacement parameters of methyl H atoms were set to 1.5U_eq(C), while those of other H atoms were set to 1.2U_eq(C). In the absence of significant anomalous scattering effects, Friedel pairs were merged.

Figures

Fig. 1.

The molecular structure of (I) showing 50% probability displacement ellipsoids.

Fig. 2.

The packing of (I), viewed down the c axis. N—H···N and N—H···Br hydrogen bond interactions are shown as dashed lines.

Crystal data

C6H5BrClN	F(000) = 424
Mr = 206.47	Dx = 1.965 Mg m−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 1199 reflections
a = 10.965 (4) Å	θ = 2.3–29.8°
b = 15.814 (6) Å	µ = 6.17 mm−1
c = 4.0232 (15) Å	T = 298 K
V = 697.7 (4) Å3	Needle, colourless
Z = 4	0.7 × 0.19 × 0.15 mm

Data collection

Bruker SMART CCD diffractometer	1710 independent reflections
Radiation source: fine-focus sealed tube	1333 reflections with I > 2σ(I)
graphite	Rint = 0.044
φ and ω scan	θmax = 29.8°, θmin = 2.3°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −14→14
Tmin = 0.254, Tmax = 0.396	k = −20→21
5799 measured reflections	l = −5→5

Refinement

Refinement on F2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F2 > 2σ(F2)] = 0.033	w = 1/[σ2(Fo2) + (0.0374P)2] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.081	(Δ/σ)max = 0.008
S = 0.99	Δρmax = 0.33 e Å−3
1710 reflections	Δρmin = −0.48 e Å−3
83 parameters	Extinction correction: SHELXTL (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraints	Extinction coefficient: 0.246 (8)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), 511 Friedel pairs
Secondary atom site location: difference Fourier map	Flack parameter: 0.035 (15)

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Br1	0.28337 (3)	0.74386 (2)	0.51936 (10)	0.0646 (2)
Cl1	0.42519 (8)	0.41363 (5)	0.4648 (3)	0.0588 (3)
C1	0.3957 (3)	0.65802 (18)	0.6258 (8)	0.0432 (7)
C2	0.4999 (3)	0.6770 (2)	0.7973 (9)	0.0494 (8)
H2A	0.5151	0.7322	0.8656	0.059*
C3	0.5812 (3)	0.6145 (2)	0.8673 (9)	0.0456 (8)
H3A	0.6518	0.6276	0.9846	0.055*
C4	0.5613 (3)	0.5320 (2)	0.7681 (8)	0.0428 (8)
C5	0.4548 (3)	0.51544 (19)	0.5957 (8)	0.0395 (7)
C6	0.3728 (2)	0.57746 (17)	0.5249 (7)	0.0431 (7)
H6A	0.3018	0.5649	0.4087	0.052*
N1	0.6464 (2)	0.47087 (18)	0.8346 (8)	0.0565 (8)
H1A	0.7124	0.4838	0.9383	0.068*
H1B	0.6338	0.4196	0.7726	0.068*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Br1	0.0770 (3)	0.0451 (2)	0.0717 (3)	0.01789 (15)	−0.0064 (2)	0.0025 (2)
Cl1	0.0638 (5)	0.0349 (4)	0.0776 (6)	−0.0034 (3)	−0.0023 (5)	−0.0047 (5)
C1	0.0509 (17)	0.0347 (16)	0.0438 (16)	0.0061 (14)	0.0043 (14)	0.0027 (13)
C2	0.0582 (18)	0.0357 (18)	0.054 (2)	−0.0081 (15)	0.0075 (16)	−0.0027 (15)
C3	0.0368 (15)	0.0481 (19)	0.0520 (18)	−0.0064 (14)	−0.0002 (14)	−0.0008 (15)
C4	0.0399 (16)	0.0430 (18)	0.0455 (18)	0.0005 (14)	0.0086 (14)	0.0040 (13)
C5	0.0416 (15)	0.0344 (15)	0.0424 (16)	−0.0028 (12)	0.0053 (13)	0.0012 (12)
C6	0.0424 (14)	0.0406 (15)	0.0461 (16)	−0.0022 (12)	−0.0007 (16)	0.0016 (16)
N1	0.0434 (15)	0.0500 (17)	0.076 (2)	0.0101 (13)	−0.0015 (15)	0.0006 (15)

Geometric parameters (Å, °)

Br1—C1	1.883 (3)	C3—H3A	0.9300
Cl1—C5	1.725 (3)	C4—N1	1.369 (4)
C1—C6	1.361 (4)	C4—C5	1.383 (4)
C1—C2	1.368 (5)	C5—C6	1.361 (4)
C2—C3	1.361 (5)	C6—H6A	0.9300
C2—H2A	0.9300	N1—H1A	0.8600
C3—C4	1.382 (4)	N1—H1B	0.8600
C6—C1—C2	120.7 (3)	C3—C4—C5	117.1 (3)
C6—C1—Br1	119.1 (2)	C6—C5—C4	121.8 (3)
C2—C1—Br1	120.2 (2)	C6—C5—Cl1	119.0 (2)
C3—C2—C1	119.4 (3)	C4—C5—Cl1	119.2 (2)
C3—C2—H2A	120.3	C1—C6—C5	119.4 (3)
C1—C2—H2A	120.3	C1—C6—H6A	120.3
C2—C3—C4	121.6 (3)	C5—C6—H6A	120.3
C2—C3—H3A	119.2	C4—N1—H1A	120.0
C4—C3—H3A	119.2	C4—N1—H1B	120.0
N1—C4—C3	120.2 (3)	H1A—N1—H1B	120.0
N1—C4—C5	122.7 (3)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1B···Br1i	0.86	3.04	3.719 (3)	137
N1—H1A···N1ii	0.86	2.34	3.172 (4)	164

Symmetry codes: (i) −x+1, y−1/2, −z+3/2; (ii) −x+3/2, −y+1, z+1/2.