(Z)-1,2-Bis(3-bromo­phen­yl)diazene 1-oxide

Goswami, S.K.; Hanton, L.R.; McAdam, C.J.; Moratti, S.C.; Simpson, J.

doi:10.1107/S2414314618014864

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 3| Part 10| October 2018| x181486

https://doi.org/10.1107/S2414314618014864

Open

access

(Z)-1,2-Bis(3-bromophenyl)diazene 1-oxide

Shailesh K. Goswami,^a Lyall R. Hanton,^a C. John McAdam,^a Stephen C. Moratti ^a and Jim Simpson ^a ^*

^aDepartment of Chemistry, University of Otago, PO Box 56, Dunedin, New Zealand
^*Correspondence e-mail: jsimpson@alkali.otago.ac.nz

Edited by S. Bernès, Benemérita Universidad Autónoma de Puebla, México (Received 19 September 2018; accepted 19 October 2018; online 26 October 2018)

The title compound C₁₂H₈Br₂N₂O, lies on an inversion centre in the space group P2₁/n. Doubts are cast on the report of a polymorph of this structure in the non-centrosymmetric space group P2₁ [Zhu, R.-T., Liu, J.-C., Jin, S., Liu, B. & Guo J.-P. (2006). Hecheng Huaxue (Chin. J. Synth. Chem.) 14, 591] as ADDSYM alerts point strongly to a centrosymmetric structure. In the crystal, C—H⋯O and C—H⋯Br hydrogen bonds together with offset π–π interactions stack the molecules along the a-axis direction.

Keywords: crystal structure; diazene; a doubtful polymorph; hydrogen bonds; π–π stacking.

CCDC reference: 1874263

Structure description

The title azoxybenzene was prepared by the reduction of 1-bromo-3-nitrobenzene. It readily undergoes a benzidine rearrangement to provide a useful precursor for substituted biphenyl diamines (Chen et al., 2011 ; Li et al., 2012 ).

The Cambridge Structural Database (CSD, version 5.39, November 2017, with four updates; Groom et al., 2016 ) reveals what appears to be a polymorph of the title compound, SIYHAK, with data collected at 293 (2) K in the non-centrosymmetric spacegroup P2₁ (Zhu et al., 2006 ). However, the CIF from this deposition generates significant ADDSYM alerts, suggesting that the correct spacegroup is P2₁/n as was found in the refinement reported here. It appears, therefore, that the earlier report is not a polymorph of the structure reported here but that they are in fact the same structures.

The title (Z)-diazene derivative, C₁₂H₈Br₂N₂O (I), lies about an inversion centre located at the mid-point of the N1=N1 diazene bond with the oxide O1 atom disordered in equal occupancy about this centre. Each diazene nitrogen atom also carries a 3-bromobenzene ring (Fig. 1). The BrC₆NO half of the molecule is almost planar with an r.m.s. deviation of only 0.0009 Å. Furthermore, the coplanar benzene rings are inclined to the O1/N1/C1 plane by 9.7 (7)°. An intramolecular C2—H2⋯O1 hydrogen bond (Table 1) supports this planarity. The N1=N1ⁱ distance observed here [1.274 (9) Å, symmetry code: (i) 1 − x, 1 − y, 1 − z] is not strikingly different from those observed in the two unique molecules of the supposed monoclinic polymorph [1.263 (5) and 1.264 (5) Å; Zhu et al., 2006], especially taking into account the significant variation in the temperatures at which the data were collected. Furthermore, this distance is also similar to the mean value, 1.27 (5) Å, observed for the 42 other similar diazene structures found in the CSD. These include the structure of the chloro analogue of (I), (Z)-1,2-bis(3-chlorophenyl)diazene 1-oxide (Jose Kavitha et al., 2003 ).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯O1ⁱ	0.95	2.07	2.722 (7)	124
C6—H6⋯O1ⁱⁱ	0.95	2.39	3.199 (8)	143
C4—H4⋯Br3ⁱⁱⁱ	0.95	3.11	3.974 (5)	151
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) -x, -y, -z+1; (iii) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Figure 1
The molecular structure of (I) showing the atom numbering with ellipsoids drawn at the 50% probability level. Labelled atoms are related to unlabelled atoms by the symmetry operation −x + 1, −y + 1, −z + 1. An intramolecular hydrogen bond is drawn as a dotted black line. In this and subsequent figures, the equivalent disorder component of the O1 atom is not shown.

In the crystal structure, C6—H6⋯O1 contacts link the molecules into C(6) chains along the b-axis direction and combine with weaker C4—H4⋯Br3 hydrogen bonds that form C(12) chains, generating sheets of molecules along the ac diagonal (Table 1, Fig. 2). Offset π–π stacking interactions with centroid-to-centroid distances of 3.894 (3) Å occur between adjacent bromobenzene rings, generating a three-dimensional network of molecules stacked along the a-axis direction (Fig. 3).

Figure 2
Sheets of molecules of (I) with hydrogen bonds shown as blue dashed lines.

Figure 3
Overall packing of (I) viewed along the a-axis direction. Representative π–π contacts are shown as dotted green lines with ring centroids drawn as red spheres.

Synthesis and crystallization

The title compound was synthesized from 1-bromo-3-nitrobenzene following a literature procedure (Chen et al., 2011). Crystals suitable for the X-ray analysis were grown by evaporation from diethyl ether solution.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. The molecule of (I) lies about an inversion centre located at the midpoint of the N1=N1 bond with the oxide O1 atom disordered in equal occupancy about this centre.

Table 2
Experimental details

Crystal data
Chemical formula	C₁₂H₈Br₂N₂O
M_r	356.02
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	90
a, b, c (Å)	3.8938 (2), 5.8223 (3), 25.8645 (16)
β (°)	92.044 (5)
V (Å³)	586.00 (6)
Z	2
Radiation type	Cu Kα
μ (mm⁻¹)	8.65
Crystal size (mm)	0.38 × 0.19 × 0.08

Data collection
Diffractometer	Agilent SuperNova, Dual, Cu at zero, Atlas
Absorption correction	Multi-scan (CrysAlis PRO; Agilent, 2014 )
T_min, T_max	0.334, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	3440, 1171, 1128
R_int	0.036
(sin θ/λ)_max (Å⁻¹)	0.626

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.049, 0.137, 1.00
No. of reflections	1171
No. of parameters	82
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.85, −0.99
Computer programs: CrysAlis PRO (Agilent, 2014), SHELXT2014 (Sheldrick, 2015a ), SHELXL2018 (Sheldrick, 2015b ), TITAN (Hunter & Simpson, 1999 ), Mercury (Macrae et al., 2008 ), enCIFer (Allen et al., 2004 ), PLATON (Spek, 2009 ), publCIF (Westrip 2010 ) and WinGX (Farrugia, 2012 ).

Structural data

CCDC reference: 1874263

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S2414314618014864/bh4042sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314618014864/bh4042Isup2.hkl

checkCIF report

Computing details top

Data collection: CrysAlis PRO (Agilent, 2014); cell refinement: CrysAlis PRO (Agilent, 2014); data reduction: CrysAlis PRO (Agilent, 2014); program(s) used to solve structure: SHELXT2014 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015b) and TITAN (Hunter & Simpson, 1999); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL2018 (Sheldrick, 2015b), enCIFer (Allen et al., 2004), PLATON (Spek, 2009), publCIF (Westrip 2010) and WinGX (Farrugia, 2012).

(Z)-1,2-Bis(3-bromophenyl)diazene 1-oxide top

Crystal data top

C₁₂H₈Br₂N₂O	F(000) = 344
M_r = 356.02	D_x = 2.018 Mg m⁻³
Monoclinic, P2₁/n	Cu Kα radiation, λ = 1.54184 Å
a = 3.8938 (2) Å	Cell parameters from 2305 reflections
b = 5.8223 (3) Å	θ = 7.6–74.4°
c = 25.8645 (16) Å	µ = 8.65 mm⁻¹
β = 92.044 (5)°	T = 90 K
V = 586.00 (6) Å³	Plate, yellow
Z = 2	0.38 × 0.19 × 0.08 mm

Data collection top

Agilent SuperNova, Dual, Cu at zero, Atlas diffractometer	1171 independent reflections
Radiation source: SuperNova (Cu) X-ray Source	1128 reflections with I > 2σ(I)
Detector resolution: 5.1725 pixels mm^-1	R_int = 0.036
ω scans	θ_max = 74.9°, θ_min = 6.9°
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2014)	h = −4→4
T_min = 0.334, T_max = 1.000	k = −7→5
3440 measured reflections	l = −31→30

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.049	H-atom parameters constrained
wR(F²) = 0.137	w = 1/[σ²(F_o²) + (0.0939P)² + 2.3574P] where P = (F_o² + 2F_c²)/3
S = 1.00	(Δ/σ)_max < 0.001
1171 reflections	Δρ_max = 0.85 e Å⁻³
82 parameters	Δρ_min = −0.99 e Å⁻³

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
O1	0.224 (2)	0.2546 (11)	0.4785 (2)	0.0334 (16)	0.5
N1	0.4136 (12)	0.4117 (7)	0.50608 (16)	0.0311 (9)
C1	0.3955 (13)	0.3550 (8)	0.56013 (19)	0.0275 (10)
C2	0.5144 (10)	0.4990 (6)	0.60040 (15)	0.0184 (8)
H2	0.618227	0.642861	0.593489	0.022*
C3	0.4750 (11)	0.4241 (7)	0.65016 (17)	0.0211 (8)
Br3	0.63666 (13)	0.61575 (9)	0.70533 (2)	0.0335 (3)
C4	0.3228 (12)	0.2162 (8)	0.6618 (2)	0.0321 (11)
H4	0.298842	0.170406	0.696715	0.038*
C5	0.2071 (14)	0.0774 (8)	0.6218 (3)	0.0407 (14)
H5	0.102440	−0.065852	0.629059	0.049*
C6	0.2435 (14)	0.1471 (8)	0.5705 (3)	0.0391 (14)
H6	0.163488	0.051244	0.542931	0.047*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.049 (4)	0.030 (3)	0.020 (3)	−0.021 (3)	−0.008 (3)	−0.003 (2)
N1	0.036 (2)	0.0327 (19)	0.024 (2)	0.0138 (16)	−0.0080 (17)	−0.0113 (15)
C1	0.025 (2)	0.028 (2)	0.029 (2)	0.0114 (18)	−0.0094 (18)	−0.0117 (17)
C2	0.020 (2)	0.0133 (17)	0.0217 (19)	0.0007 (14)	−0.0023 (15)	−0.0010 (14)
C3	0.018 (2)	0.0245 (19)	0.021 (2)	0.0052 (16)	0.0023 (15)	−0.0020 (15)
Br3	0.0287 (4)	0.0520 (4)	0.0192 (4)	0.0121 (2)	−0.0056 (2)	−0.01095 (18)
C4	0.026 (2)	0.024 (2)	0.047 (3)	0.0106 (18)	0.0119 (19)	0.019 (2)
C5	0.021 (3)	0.0147 (19)	0.087 (5)	−0.0004 (17)	0.008 (3)	0.006 (2)
C6	0.022 (2)	0.025 (2)	0.069 (4)	0.0057 (18)	−0.013 (2)	−0.022 (2)

Geometric parameters (Å, º) top

O1—N1	1.360 (7)	C3—C4	1.385 (6)
N1—N1ⁱ	1.274 (9)	C3—Br3	1.901 (4)
N1—C1	1.440 (7)	C4—C5	1.375 (9)
C1—C6	1.378 (8)	C4—H4	0.9500
C1—C2	1.403 (6)	C5—C6	1.399 (10)
C2—C3	1.373 (6)	C5—H5	0.9500
C2—H2	0.9500	C6—H6	0.9500

N1ⁱ—N1—O1	134.0 (6)	C4—C3—Br3	118.9 (4)
N1ⁱ—N1—C1	118.0 (5)	C5—C4—C3	118.8 (5)
O1—N1—C1	108.0 (5)	C5—C4—H4	120.6
C6—C1—C2	120.8 (5)	C3—C4—H4	120.6
C6—C1—N1	115.3 (4)	C4—C5—C6	120.0 (4)
C2—C1—N1	123.9 (4)	C4—C5—H5	120.0
C3—C2—C1	117.5 (4)	C6—C5—H5	120.0
C3—C2—H2	121.3	C1—C6—C5	119.9 (5)
C1—C2—H2	121.3	C1—C6—H6	120.0
C2—C3—C4	122.9 (4)	C5—C6—H6	120.0
C2—C3—Br3	118.2 (3)

N1ⁱ—N1—C1—C6	−172.0 (5)	C1—C2—C3—Br3	179.7 (3)
O1—N1—C1—C6	9.0 (6)	C2—C3—C4—C5	0.3 (7)
N1ⁱ—N1—C1—C2	9.4 (8)	Br3—C3—C4—C5	−179.8 (4)
O1—N1—C1—C2	−169.6 (5)	C3—C4—C5—C6	−0.1 (7)
C6—C1—C2—C3	0.4 (6)	C2—C1—C6—C5	−0.1 (7)
N1—C1—C2—C3	178.9 (4)	N1—C1—C6—C5	−178.8 (4)
C1—C2—C3—C4	−0.5 (6)	C4—C5—C6—C1	0.0 (7)

Symmetry code: (i) −x+1, −y+1, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O1ⁱ	0.95	2.07	2.722 (7)	124
C6—H6···O1ⁱⁱ	0.95	2.39	3.199 (8)	143
C4—H4···Br3ⁱⁱⁱ	0.95	3.11	3.974 (5)	151

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

Funding information

We thank the NZ Ministry of Business, Innovation and Employment Science Investment Fund (grant No. UOOX1206) for support of this work and the University of Otago for the purchase of the diffractometer. JS thanks the Chemistry Department, University of Otago, for the support of his work.

References

Agilent (2014). CrysAlis PRO. Agilent Technologies, Yarnton, England. Google Scholar
Allen, F. H., Johnson, O., Shields, G. P., Smith, B. R. & Towler, M. (2004). J. Appl. Cryst. 37, 335–338. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Chen, J.-C., Liu, Y.-C., Ju, J.-J., Chiang, C.-J. & Chern, Y.-T. (2011). Polymer, 52, 954–964. Web of Science CrossRef Google Scholar
Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849–854. Web of Science CrossRef CAS IUCr Journals Google Scholar
Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171–179. Web of Science CSD CrossRef IUCr Journals Google Scholar
Hunter, K. A. & Simpson, J. (1999). TITAN2000. University of Otago, New Zealand. Google Scholar
Jose Kavitha, S., Chandrasekar, S. & Panchanatheswaran, K. (2003). Acta Cryst. E59, o947–o949. Web of Science CrossRef IUCr Journals Google Scholar
Li, Y., Chu, Y., Fang, R., Ding, S., Wang, Y., Shen, Y. & Zheng, A. (2012). Polymer, 53, 229–240. Web of Science CrossRef Google Scholar
Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466–470. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (2015a). Acta Cryst. A71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2015b). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar
Westrip, S. P. (2010). J. Appl. Cryst. 43, 920–925. Web of Science CrossRef CAS IUCr Journals Google Scholar
Zhu, R.-T., Liu, J.-C., Jin, S., Liu, B. & Guo, J.-P. (2006). Hecheng Huaxue, 14, 591–593. Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.