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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 4| April 2011| Page o976
doi:10.1107/S160053681101052X

4-Bromo-N-phenyl­aniline

Emily J. Heftera and Joseph M. Tanskia*

aDepartment of Chemistry, Vassar College, Poughkeepsie, NY 12604, USA
*Correspondence e-mail: jotanski@vassar.edu

(Received 10 March 2011; accepted 21 March 2011; online 26 March 2011)

In the title compound, C12H10BrN, the dihedral angle between the benzene rings is 52.5 (1)°, whereas the pitch angles, or the angles between the mean plane of each aryl group `propeller blade' and the plane defined by the aryl bridging C—N—C angle, are 19.6 (2) and 36.2 (3)°. While the N—H group is not involved in hydrogen-bonding inter­actions, the structure exhibits a network of inter­molecular C—H⋯π and N—H⋯π inter­actions.

Related literature

The title compound is an amine analogue of brominated diphenyl ether flame retardant materials commonly used in household items. For information on environmental and health concerns related to brominated flame retardants, see: de Wit (2002[Wit, C. A. de (2002). Chemosphere, 46, 583-624.]); Lunder et al. (2010[Lunder, S., Hovander, L., Athanassiadis, I. & Bergman, A. (2010). Environ. Sci. Technol. 44, 5256-5262.]). For the synthesis, see: He et al. (2008[He, C., Chen, C., Cheng, J., Liu, C., Liu, W., Li, Q. & Lei, A. (2008). Angew. Chem. Int. Ed. 47, 6414-6417.]); Sus (1947[Sus, O. (1947). Annalen der Chemie 557, 237-242.]). For a related structure and information on C—H⋯π and N—H⋯π inter­actions, see: Krzymiński et al. (2009[Krzymiński, K., Wera, M., Sikorski, A. & Błażejowski, J. (2009). Acta Cryst. E65, o152.]). For a description of the pitch angle in similar diphenyl structures, see: Duong & Tanski (2011[Duong, M. M. & Tanski, J. M. (2011). Acta Cryst. E67, o755.]); Lim & Tanski (2007[Lim, C. F. & Tanski, J. M. (2007). J. Chem. Crystallogr. 37, 587-595.]).

[Scheme 1]

Experimental

Crystal data

  • C12H10BrN

  • Mr = 248.12

  • Orthorhombic, P c c n

  • a = 15.6741 (6) Å

  • b = 17.7531 (7) Å

  • c = 7.3608 (3) Å

  • V = 2048.24 (14) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 3.97 mm−1

  • T = 125 K

  • 0.31 × 0.21 × 0.04 mm
Data collection

  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker 2007[Bruker (2007). APEX2, SADABS and SAINT. BrukerAXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.373, Tmax = 0.857

  • 31081 measured reflections

  • 3137 independent reflections

  • 2552 reflections with I > 2σ(I)

  • Rint = 0.038
Refinement

  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.118

  • S = 1.07

  • 3137 reflections

  • 130 parameters

  • 1 restraint

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 1.72 e Å−3

  • Δρmin = −0.77 e Å−3

Table 1
C—H⋯π and N—H⋯π interactions (Å, °)

Cg1 and Cg2 are the centroids of the C1–C6 and C7–C12 rings, respectively.
D—H⋯A D—H H⋯A D⋯A D—H⋯A
C6—H6⋯Cg2i 0.95 2.69 3.404 (3) 132
N1—H1⋯Cg1ii 0.85 (2) 2.65 3.501 (2) 175
C9—H9⋯Cg1iii 0.95 2.96 3.651 (3) 131
Symmetry codes: (i) x, y, z-1; (ii) [x-{\script{1\over 2}}, y+{\script{3\over 2}}, -z]; (iii) [-x+{\script{1\over 2}}, -y+{\script{3\over 2}}, z+2].

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2, SADABS and SAINT. BrukerAXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). APEX2, SADABS and SAINT. BrukerAXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL and Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053681101052X/om2415sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681101052X/om2415Isup2.hkl

checkCIF report


Comment top

Diphenylamines have uses in chemical synthesis and materials chemistry, and they have been investigated for their biological activity (Krzymiński et al., 2009). The title compound, a brominated diphenyl amine, was first synthesized by the photolysis of 4-diazodiphenylamine in the presence of HBr (Sus, 1947). More recently, halogenated diphenylamines have been prepared by copper catalyzed coupling reactions (He et al., 2008). The title compound is an amine analogue of a class of brominated diphenyl ether materials (de Wit, 2002). Polybrominated diphenyl ethers are commonly used as flame retardants in consumer products and electronics and have been found in humans (Lunder et al., 2010). The title compound is a monobrominated diphenyl amine derivative with a "propeller blade" disposition of the aryl rings about the bridging nitrogen atom. The aryl-bridging C4-N1-C7 angle is 126.4 (2)°, similar to the C-N-C bond angle of 126.1 (2)° found in the isomorphous structure of 4-methoxy-N-phenylaniline (Krzymiński et al., 2009). The dihedral angle is found to be 52.5 (1)°, whereas the pitch angles are 19.6 (2)° and 36.2 (3)°. The pitch angles are the angles between the mean plane of each aryl group "propeller blade" and the plane defined by the three atoms C4-N1-C7 (Lim & Tanski, 2007; Duong & Tanski, 2011). In 4-methoxy-N-phenylaniline, the dihedral angle is somewhat larger, 59.9 (2)° (Krzymiński et al., 2009), whereas the pitch angles, 7.2° and 53.8°, are very different, exemplifying how analogous structures with similar dihedral angles may have dramatically different dispostions of the aryl groups about the bridging atom.

The structure reveals that there is no intermolecular hydrogen bonding, however, a network of intermolecular C—H···π and N—H···π bonds exists (Table 1), as in the isomorphous structure of 4-methoxy-N-phenylaniline (Krzymiński et al., 2009). These interactions are shorter in the title compound. The N—H···π centroid distance of 2.65 Å (Fig. 2) is shorter than the 2.88 Å distance observed in 4-methoxy-N-phenylaniline, and the N—H···π centroid angle of 175° is closer to linear than the 142° angle observed in 4-methoxy-N-phenylaniline, resulting in an interaction where the amine proton is directed at the center of the aromatic ring (Fig. 2), as opposed to at the edge of the ring as found the structure of 4-methoxy-N-phenylaniline.

Related literature top

The title compound is an amine analogue of brominated diphenyl ether flame retardant materials commonly used in household items. For information on environmental and health concerns related to brominated flame retardants, see: de Wit (2002); Lunder et al. (2010). For the synthesis, see: He et al. (2008); Sus (1947). For a related structure and information on C—H···π and N—H···π interactions, see: Krzymiński et al. (2009). For a description of the pitch angle in similar diphenyl structures, see: Duong & Tanski (2011); Lim & Tanski (2007).

Experimental top

Crystalline 4-bromo-N-phenylaniline was purchased from Aldrich Chemical Company, USA.

Refinement top

All non-hydrogen atoms were refined anisotropically. Hydrogen atoms on carbon were included in calculated positions and were refined using a riding model at C–H = 0.95Å and Uiso(H) = 1.2 × Ueq(C) of the aryl C-atoms. The hydrogen atom on nitrogen was refined semifreely with the help of a distance restraint, d(N–H) = 0.85 (2) Å and Uiso(H) = 1.2 × Ueq(N). There are three difference peaks > 1 e/Å3. The first and third highest difference peaks of 1.72 and 1.10 e/Å3 are < 0.8 Å from Br1, and the second highest difference peak of 1.64 e/Å3 is very close to the calculated H10 position. The extinction parameter (EXTI) refined to zero and was removed from the refinement.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006).

Figures top
[Figure 1] Fig. 1. A view of the title compound, with displacement ellipsoids shown at the 50% probability level.
[Figure 2] Fig. 2. A view of the N—H···π intermolecular interaction with displacement ellipsoids shown at the 50% probability level [Symmetry codes: (i) x - 1/2, y + 3/2, -z].
4-Bromo-N-phenylaniline top
Crystal data top
C12H10BrNF(000) = 992
Mr = 248.12Dx = 1.609 Mg m−3
Orthorhombic, PccnMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ab 2acCell parameters from 9926 reflections
a = 15.6741 (6) Åθ = 2.3–30.2°
b = 17.7531 (7) ŵ = 3.97 mm−1
c = 7.3608 (3) ÅT = 125 K
V = 2048.24 (14) Å3Plate, colourless
Z = 80.31 × 0.21 × 0.04 mm
Data collection top
Bruker APEXII CCD
diffractometer		3137 independent reflections
Radiation source: fine-focus sealed tube2552 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.038
ϕ and ω scansθmax = 30.5°, θmin = 1.7°
Absorption correction: multi-scan
(SADABS; Bruker 2007)		h = −22→22
Tmin = 0.373, Tmax = 0.857k = −25→25
31081 measured reflectionsl = −10→10
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.118H atoms treated by a mixture of independent and constrained refinement
S = 1.07 w = 1/[σ2(Fo2) + (0.0513P)2 + 4.1415P]
where P = (Fo2 + 2Fc2)/3
3137 reflections(Δ/σ)max = 0.001
130 parametersΔρmax = 1.72 e Å−3
1 restraintΔρmin = −0.77 e Å−3
Crystal data top
C12H10BrNV = 2048.24 (14) Å3
Mr = 248.12Z = 8
Orthorhombic, PccnMo Kα radiation
a = 15.6741 (6) ŵ = 3.97 mm−1
b = 17.7531 (7) ÅT = 125 K
c = 7.3608 (3) Å0.31 × 0.21 × 0.04 mm
Data collection top
Bruker APEXII CCD
diffractometer		3137 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker 2007)		2552 reflections with I > 2σ(I)
Tmin = 0.373, Tmax = 0.857Rint = 0.038
31081 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0431 restraint
wR(F2) = 0.118H atoms treated by a mixture of independent and constrained refinement
S = 1.07Δρmax = 1.72 e Å−3
3137 reflectionsΔρmin = −0.77 e Å−3
130 parameters
Special details top

Experimental. A suitable crystal was mounted in a nylon loop with Paratone-N cryoprotectant oil.

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes and the e.s.d. for hydrogen-pi acceptor interactions) 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. Esds for the hydrogen-pi acceptor interactions are taken as the e.s.d.'s on the hydrogen donor to mean plane of the pi-acceptor distances.

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Br10.14415 (2)0.595132 (18)0.26943 (4)0.03453 (12)
N1−0.02798 (16)0.68765 (12)0.9753 (3)0.0256 (5)
H1−0.009 (2)0.7273 (14)1.025 (4)0.031*
C10.09072 (18)0.62304 (14)0.4908 (4)0.0237 (5)
C20.13506 (17)0.66570 (15)0.6173 (4)0.0250 (5)
H20.19200.68110.59360.030*
C30.09542 (18)0.68562 (15)0.7787 (4)0.0248 (5)
H30.12580.71480.86540.030*
C40.01153 (17)0.66358 (14)0.8166 (3)0.0220 (5)
C5−0.03227 (17)0.62058 (14)0.6857 (3)0.0225 (5)
H5−0.08930.60520.70820.027*
C60.00745 (18)0.60043 (14)0.5232 (3)0.0228 (5)
H6−0.02240.57140.43530.027*
C7−0.08697 (16)0.64678 (14)1.0792 (3)0.0220 (5)
C8−0.09352 (17)0.56827 (14)1.0688 (4)0.0233 (5)
H8−0.05930.54120.98460.028*
C9−0.14950 (19)0.52990 (17)1.1805 (4)0.0294 (6)
H9−0.15340.47661.17210.035*
C10−0.2008 (2)0.5685 (2)1.3063 (4)0.0343 (6)
H10−0.23890.54191.38350.041*
C11−0.19422 (19)0.6463 (2)1.3148 (4)0.0338 (6)
H11−0.22840.67331.39930.041*
C12−0.13888 (18)0.68566 (16)1.2028 (4)0.0271 (5)
H12−0.13610.73901.20980.033*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.03463 (18)0.03743 (18)0.03153 (17)0.00533 (12)0.00963 (12)−0.00285 (11)
N10.0360 (12)0.0194 (9)0.0213 (10)−0.0046 (9)0.0032 (9)−0.0044 (8)
C10.0275 (12)0.0196 (11)0.0241 (12)0.0050 (9)0.0014 (10)0.0036 (9)
C20.0217 (12)0.0233 (11)0.0301 (13)−0.0011 (9)−0.0001 (10)0.0059 (10)
C30.0286 (12)0.0211 (11)0.0246 (12)−0.0041 (9)−0.0039 (10)0.0020 (9)
C40.0299 (13)0.0175 (10)0.0187 (11)−0.0007 (9)−0.0005 (9)0.0014 (8)
C50.0238 (12)0.0238 (11)0.0200 (11)−0.0010 (9)−0.0011 (9)−0.0012 (9)
C60.0283 (12)0.0203 (11)0.0198 (11)0.0000 (9)−0.0017 (9)−0.0003 (9)
C70.0233 (12)0.0232 (11)0.0194 (11)0.0023 (9)−0.0033 (9)−0.0004 (9)
C80.0255 (12)0.0219 (11)0.0225 (11)0.0024 (9)−0.0021 (9)−0.0016 (9)
C90.0315 (14)0.0302 (13)0.0266 (13)−0.0056 (11)−0.0024 (11)0.0023 (10)
C100.0287 (14)0.0461 (17)0.0280 (14)−0.0090 (13)0.0008 (11)−0.0012 (12)
C110.0255 (13)0.0497 (18)0.0263 (13)0.0019 (12)0.0033 (11)−0.0095 (12)
C120.0275 (13)0.0283 (13)0.0257 (12)0.0046 (10)−0.0027 (10)−0.0053 (10)
Geometric parameters (Å, º) top
Br1—C11.898 (3)C6—H60.9500
N1—C41.389 (3)C7—C81.400 (4)
N1—C71.402 (3)C7—C121.402 (4)
N1—H10.849 (18)C8—C91.382 (4)
C1—C61.386 (4)C8—H80.9500
C1—C21.387 (4)C9—C101.404 (4)
C2—C31.387 (4)C9—H90.9500
C2—H20.9500C10—C111.388 (5)
C3—C41.400 (4)C10—H100.9500
C3—H30.9500C11—C121.385 (4)
C4—C51.408 (4)C11—H110.9500
C5—C61.395 (4)C12—H120.9500
C5—H50.9500
C4—N1—C7126.4 (2)C5—C6—H6120.2
C4—N1—H1117 (2)C8—C7—N1122.3 (2)
C7—N1—H1115 (2)C8—C7—C12118.9 (2)
C6—C1—C2121.0 (2)N1—C7—C12118.8 (2)
C6—C1—Br1119.2 (2)C9—C8—C7120.3 (3)
C2—C1—Br1119.9 (2)C9—C8—H8119.8
C3—C2—C1119.3 (2)C7—C8—H8119.8
C3—C2—H2120.3C8—C9—C10121.0 (3)
C1—C2—H2120.3C8—C9—H9119.5
C2—C3—C4121.4 (2)C10—C9—H9119.5
C2—C3—H3119.3C11—C10—C9118.2 (3)
C4—C3—H3119.3C11—C10—H10120.9
N1—C4—C3120.0 (2)C9—C10—H10120.9
N1—C4—C5121.6 (2)C12—C11—C10121.4 (3)
C3—C4—C5118.2 (2)C12—C11—H11119.3
C6—C5—C4120.5 (2)C10—C11—H11119.3
C6—C5—H5119.7C11—C12—C7120.1 (3)
C4—C5—H5119.7C11—C12—H12120.0
C1—C6—C5119.6 (2)C7—C12—H12120.0
C1—C6—H6120.2
C6—C1—C2—C30.3 (4)C4—C5—C6—C10.0 (4)
Br1—C1—C2—C3−179.87 (19)C4—N1—C7—C820.8 (4)
C1—C2—C3—C40.0 (4)C4—N1—C7—C12−161.7 (3)
C7—N1—C4—C3−145.7 (3)N1—C7—C8—C9176.6 (3)
C7—N1—C4—C538.0 (4)C12—C7—C8—C9−0.8 (4)
C2—C3—C4—N1−176.7 (2)C7—C8—C9—C100.0 (4)
C2—C3—C4—C5−0.2 (4)C8—C9—C10—C110.4 (4)
N1—C4—C5—C6176.6 (2)C9—C10—C11—C120.1 (4)
C3—C4—C5—C60.3 (4)C10—C11—C12—C7−1.0 (4)
C2—C1—C6—C5−0.3 (4)C8—C7—C12—C111.3 (4)
Br1—C1—C6—C5179.89 (19)N1—C7—C12—C11−176.2 (3)
Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of the C1–C6 and C7–C12 rings, respectively.
D—H···AD—HH···AD···AD—H···A
C6—H6···Cg2i0.952.693.404 (3)132
N1—H1···Cg1ii0.85 (2)2.653.501 (2)175
C9—H9···Cg1iii0.952.963.651 (3)131
Symmetry codes: (i) x, y, z−1; (ii) x−1/2, y+3/2, −z; (iii) −x+1/2, −y+3/2, z+2.

Experimental details

Crystal data
Chemical formulaC12H10BrN
Mr248.12
Crystal system, space groupOrthorhombic, Pccn
Temperature (K)125
a, b, c (Å)15.6741 (6), 17.7531 (7), 7.3608 (3)
V (Å3)2048.24 (14)
Z8
Radiation typeMo Kα
µ (mm−1)3.97
Crystal size (mm)0.31 × 0.21 × 0.04
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker 2007)
Tmin, Tmax0.373, 0.857
No. of measured, independent and
observed [I > 2σ(I)] reflections		31081, 3137, 2552
Rint0.038
(sin θ/λ)max (Å−1)0.714
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.043, 0.118, 1.07
No. of reflections3137
No. of parameters130
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)1.72, −0.77

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006).

Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of the C1–C6 and C7–C12 rings, respectively.
D—H···AD—HH···AD···AD—H···A
C6—H6···Cg2i0.952.693.404 (3)132
N1—H1···Cg1ii0.85 (2)2.653.501 (2)175
C9—H9···Cg1iii0.952.963.651 (3)131
Symmetry codes: (i) x, y, z−1; (ii) x−1/2, y+3/2, −z; (iii) −x+1/2, −y+3/2, z+2.
 

Acknowledgements

This work was supported by Vassar College. X-ray facilities were provided by the US National Science Foundation (grant No. 0521237 to JMT).

References

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COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 4| April 2011| Page o976
doi:10.1107/S160053681101052X
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