Crystal structure of 2-bromo-4,6-di­nitroaniline

Abstract

In the title compound, C₆H₄BrN₃O₄, the dihedral angles between the nitro groups and the aniline ring are 2.04 (3) and 1.18 (4)°, respectively. In the crystal, N—H⋯O and C—H⋯O hydrogen bonds and weak side-on C—Br⋯π inter­actions [3.5024 (12) Å] link adjacent mol­ecules, forming a three-dimensional network. A close O⋯Br contact [3.259 (2) Å] may also add additional stability.

Related literature  

For information on the title compound, see: Yadav & Sharma (2010 ▸). For a related crystal structure, see: Glidewell et al. (2002 ▸).

Experimental  

Crystal data  

• C₆H₄BrN₃O₄

• M _r = 262.03

• Monoclinic

• a = 6.6955 (2) Å

• b = 7.7720 (2) Å

• c = 16.0608 (4) Å

• β = 95.4182 (14)°

• V = 832.03 (4) ų

• Z = 4

• Mo Kα radiation

• μ = 4.93 mm⁻¹

• T = 173 K

• 0.20 × 0.15 × 0.08 mm

Data collection  

• Bruker APEXII CCD diffractometer

• Absorption correction: multi-scan (SADABS; Bruker, 2013 ▸) T _min = 0.534, T _max = 0.746

• 12322 measured reflections

• 1892 independent reflections

• 1648 reflections with I > 2σ(I)

• R _int = 0.030

Refinement  

• R[F ² > 2σ(F ²)] = 0.033

• wR(F ²) = 0.083

• S = 1.06

• 1892 reflections

• 127 parameters

• H-atom parameters constrained

• Δρ_max = 0.85 e Å⁻³

• Δρ_min = −0.51 e Å⁻³

Data collection: APEX2 (Bruker, 2013 ▸); cell refinement: SAINT (Bruker, 2013 ▸); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▸); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2015 ▸); molecular graphics: DIAMOND (Brandenburg, 2010 ▸); software used to prepare material for publication: SHELXTL (Sheldrick, 2008 ▸).

Supplementary Material

CCDC reference: 1427403

Additional supporting information: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (, ).

DHA	DH	HA	D A	DHA
N1H1AO2i	0.88	2.16	2.893(3)	141
N1H1BO4ii	0.88	2.36	3.139(4)	148
C5H5O1iii	0.95	2.55	3.209(4)	127

Symmetry codes: (i) ; (ii) ; (iii) .

supplementary crystallographic information

S1. Comment

The title compound, C₆H₄BrN₃O₄, is an aniline derivative with additional bromine and nitro substituents. Aniline is the simplest of the primary aromatic amines an organic base used, as are its derivatives, to make dyes, drugs, explosives, plastics and chemicals for the rubber industry (Yadav & Sharma, 2010). Its crystal structure is reported herein. In this compound (Fig. 1), the dihedral angles between the nitro groups and the aniline ring are 2.04 (3) and 1.18 (4)°, respectively. All bond lengths and bond angles are normal and comparable to those observed in the crystal structure of a similar compound (Glidewell et al., 2002).

The crystal structure (Fig. 2) is stabilized by N—H···O and C—H···O hydrogen bonds (Table 1), as well as an intermolecular side-on C2—Br1···Cg1^iv interaction [Br1···Cg = 3.5024 (12) Å, C2—Br1···Cg = 96.90 (9) °] (Cg1 is the centroid of the C1–C6 ring) [symmetry code: (iv), -x, -y + 1, -z + 2]. A close O3···Br1^iv contact, 3.259 (2) Å may also contribute, iv = -1/2+x,1.5-y, -1/2+z. These contacts result in a three-dimensional network.

S2. Experimental

The title compound was supplied by the Kyung In Synthetic Corporation. Slow evaporation of a solution in CH₂Cl₂ gave single crystals suitable for X-ray analysis.

S3. Refinement

All H-atoms were positioned geometrically and refined using a riding model with d(N—H) = 0.88 Å, U_iso = 1.2U_eq(C) for amine group, d(C—H) = 0.95 Å, U_iso = 1.2U_eq(C) for aromatic C—H.

Figures

Fig. 1.

The asymmetric unit of the title compound with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are shown as small spheres of arbitrary radius.

Fig. 2.

Crystal packing viewed along the a axis. The intermolecular interactions are shown as dashed lines.

Crystal data

C6H4BrN3O4	F(000) = 512
Mr = 262.03	Dx = 2.092 Mg m−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
a = 6.6955 (2) Å	Cell parameters from 6099 reflections
b = 7.7720 (2) Å	θ = 2.6–27.1°
c = 16.0608 (4) Å	µ = 4.93 mm−1
β = 95.4182 (14)°	T = 173 K
V = 832.03 (4) Å3	Block, yellow
Z = 4	0.20 × 0.15 × 0.08 mm

Data collection

Bruker APEXII CCD diffractometer	1648 reflections with I > 2σ(I)
φ and ω scans	Rint = 0.030
Absorption correction: multi-scan (SADABS; Bruker, 2013)	θmax = 27.5°, θmin = 2.6°
Tmin = 0.534, Tmax = 0.746	h = −8→8
12322 measured reflections	k = −10→10
1892 independent reflections	l = −20→20

Refinement

Refinement on F2	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.033	H-atom parameters constrained
wR(F2) = 0.083	w = 1/[σ2(Fo2) + (0.0334P)2 + 1.6027P] where P = (Fo2 + 2Fc2)/3
S = 1.06	(Δ/σ)max = 0.002
1892 reflections	Δρmax = 0.85 e Å−3
127 parameters	Δρmin = −0.51 e Å−3

Special details

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.

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

	x	y	z	Uiso*/Ueq
Br1	0.19258 (6)	0.64018 (4)	1.10024 (2)	0.04116 (14)
O1	0.4575 (4)	0.6238 (3)	0.79915 (19)	0.0484 (7)
O2	0.2420 (4)	0.7493 (4)	0.71047 (15)	0.0544 (8)
O3	−0.3569 (3)	0.9745 (3)	0.79238 (13)	0.0379 (5)
O4	−0.4360 (3)	0.9614 (3)	0.91874 (15)	0.0397 (6)
N1	−0.1949 (4)	0.8183 (4)	1.03776 (15)	0.0327 (6)
H1A	−0.1531	0.7837	1.0886	0.039*
H1B	−0.3120	0.8696	1.0282	0.039*
N2	0.2978 (4)	0.6977 (4)	0.78113 (17)	0.0348 (6)
N3	−0.3276 (3)	0.9358 (3)	0.86609 (13)	0.0212 (5)
C1	−0.0806 (4)	0.7930 (4)	0.97511 (16)	0.0230 (6)
C2	0.1093 (4)	0.7101 (4)	0.98987 (17)	0.0256 (6)
C3	0.2302 (4)	0.6777 (4)	0.92827 (19)	0.0277 (6)
H3	0.3551	0.6208	0.9404	0.033*
C4	0.1671 (4)	0.7299 (4)	0.84695 (18)	0.0263 (6)
C5	−0.0114 (4)	0.8115 (4)	0.82743 (17)	0.0233 (6)
H5	−0.0513	0.8456	0.7715	0.028*
C6	−0.1333 (4)	0.8435 (3)	0.89051 (16)	0.0214 (5)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Br1	0.0571 (2)	0.0375 (2)	0.02593 (18)	−0.01145 (16)	−0.01191 (14)	0.00718 (13)
O1	0.0422 (14)	0.0411 (14)	0.0655 (18)	0.0096 (11)	0.0239 (13)	−0.0063 (12)
O2	0.0471 (15)	0.094 (2)	0.0241 (12)	−0.0027 (15)	0.0165 (11)	−0.0089 (13)
O3	0.0415 (13)	0.0450 (14)	0.0268 (11)	0.0051 (11)	0.0004 (10)	0.0036 (10)
O4	0.0329 (12)	0.0438 (14)	0.0437 (14)	0.0057 (10)	0.0111 (11)	0.0000 (11)
N1	0.0409 (15)	0.0416 (15)	0.0168 (11)	−0.0026 (12)	0.0096 (11)	−0.0002 (11)
N2	0.0351 (15)	0.0381 (15)	0.0340 (15)	−0.0082 (12)	0.0174 (12)	−0.0124 (12)
N3	0.0269 (12)	0.0220 (11)	0.0147 (10)	−0.0105 (9)	0.0011 (9)	0.0003 (9)
C1	0.0323 (15)	0.0214 (13)	0.0156 (12)	−0.0095 (11)	0.0051 (11)	−0.0032 (10)
C2	0.0339 (15)	0.0246 (14)	0.0175 (13)	−0.0095 (12)	−0.0025 (11)	0.0019 (11)
C3	0.0274 (14)	0.0242 (14)	0.0308 (15)	−0.0045 (11)	−0.0010 (12)	−0.0003 (12)
C4	0.0290 (15)	0.0289 (15)	0.0224 (13)	−0.0054 (12)	0.0100 (12)	−0.0058 (11)
C5	0.0276 (14)	0.0274 (14)	0.0153 (12)	−0.0069 (11)	0.0046 (11)	−0.0009 (10)
C6	0.0257 (13)	0.0218 (13)	0.0170 (12)	−0.0045 (11)	0.0031 (10)	−0.0019 (10)

Geometric parameters (Å, º)

Br1—C2	1.887 (3)	N3—C6	1.505 (4)
O1—N2	1.224 (4)	C1—C2	1.425 (4)
O2—N2	1.228 (4)	C1—C6	1.426 (4)
O3—N3	1.219 (3)	C2—C3	1.360 (4)
O4—N3	1.182 (3)	C3—C4	1.395 (4)
N1—C1	1.335 (4)	C3—H3	0.9500
N1—H1A	0.8800	C4—C5	1.363 (4)
N1—H1B	0.8800	C5—C6	1.382 (4)
N2—C4	1.456 (4)	C5—H5	0.9500
C1—N1—H1A	120.0	C1—C2—Br1	117.8 (2)
C1—N1—H1B	120.0	C2—C3—C4	118.6 (3)
H1A—N1—H1B	120.0	C2—C3—H3	120.7
O1—N2—O2	123.7 (3)	C4—C3—H3	120.7
O1—N2—C4	118.7 (3)	C5—C4—C3	122.2 (3)
O2—N2—C4	117.6 (3)	C5—C4—N2	119.1 (3)
O4—N3—O3	126.8 (3)	C3—C4—N2	118.7 (3)
O4—N3—C6	117.9 (2)	C4—C5—C6	118.7 (3)
O3—N3—C6	115.3 (2)	C4—C5—H5	120.6
N1—C1—C2	120.5 (3)	C6—C5—H5	120.6
N1—C1—C6	124.7 (3)	C5—C6—C1	122.6 (3)
C2—C1—C6	114.8 (2)	C5—C6—N3	116.8 (2)
C3—C2—C1	123.1 (3)	C1—C6—N3	120.6 (2)
C3—C2—Br1	119.1 (2)
N1—C1—C2—C3	178.6 (3)	C3—C4—C5—C6	0.1 (4)
C6—C1—C2—C3	−1.3 (4)	N2—C4—C5—C6	−179.2 (3)
N1—C1—C2—Br1	−0.5 (4)	C4—C5—C6—C1	−0.7 (4)
C6—C1—C2—Br1	179.52 (19)	C4—C5—C6—N3	179.3 (2)
C1—C2—C3—C4	0.9 (4)	N1—C1—C6—C5	−178.7 (3)
Br1—C2—C3—C4	180.0 (2)	C2—C1—C6—C5	1.3 (4)
C2—C3—C4—C5	−0.2 (4)	N1—C1—C6—N3	1.3 (4)
C2—C3—C4—N2	179.1 (3)	C2—C1—C6—N3	−178.7 (2)
O1—N2—C4—C5	−179.7 (3)	O4—N3—C6—C5	178.5 (3)
O2—N2—C4—C5	1.4 (4)	O3—N3—C6—C5	−0.6 (3)
O1—N2—C4—C3	1.0 (4)	O4—N3—C6—C1	−1.5 (4)
O2—N2—C4—C3	−177.9 (3)	O3—N3—C6—C1	179.4 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O2i	0.88	2.16	2.893 (3)	141
N1—H1B···O4ii	0.88	2.36	3.139 (4)	148
C5—H5···O1iii	0.95	2.55	3.209 (4)	127

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