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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 69| Part 8| August 2013| Page o1250
doi:10.1107/S1600536813018977

(E)-1-[(2,4,6-Tri­bromo­phen­yl)diazen­yl]naphthalen-2-ol

Souheyla Chetioui,a Issam Boudraa,a* Sofiane Bouacida,a Abdelkader Bouchoula and Salah Eddine Bouaouda

aUnité de Recherche de Chimie de l'Environnement et Moléculaire Structurale (CHEMS), Faculté des Sciences Exactes, Département de Chimie, Université Constantine 1, 25000 Constantine, Algeria
*Correspondence e-mail: issam.boudraa@gmail.com

(Received 3 July 2013; accepted 9 July 2013; online 13 July 2013)

The title azo mol­ecule, C16H9Br3N2O, adopts a trans conformation with respect to the azo N=N double bond. An intra­molecular O—H⋯N hydrogen bond forms an S(6) ring motif. The dihedral angle between the naphthalene ring system and the benzene ring is 33.80 (16)°. In the crystal, mol­ecules are stacked in columns along the a axis by π–π inter­actions [centroid–centroid distances = 3.815 (3) and 3.990 (3) Å].

Related literature

For applications of azo compounds, see: Gale et al. (1998[Gale, P. A., Chen, Z., Drew, M. G. B., Heath, J. A. & Beer, P. D. (1998). Polyhedron, 4, 405-412.]). For the synthesis of similar compounds, see: Wang et al. (2003[Wang, M., Funabiki, K. & Matsui, M. (2003). Dyes Pigm. 57, 77-86.]); Heinrich et al. (2007[Heinrich, M. R., Blank, O. & Wetzel, A. (2007). J. Org. Chem. 72, 476-484.]). For bond lengths and angles in related azo compounds, see: Deveci et al. (2005[Deveci, O., Işık, S., Albayrak, C. & Ağar, E. (2005). Acta Cryst. E61, o3226-o3227.]); El-Ghamry et al. (2008[El-Ghamry, H., Issa, R., El-Baradie, K., Isagai, K., Masaoka, S. & Sakai, K. (2008). Acta Cryst. E64, o1673-o1674.]).

[Scheme 1]

Experimental

Crystal data

  • C16H9Br3N2O

  • Mr = 484.98

  • Orthorhombic, P 21 21 21

  • a = 3.9904 (11) Å

  • b = 15.689 (4) Å

  • c = 24.580 (7) Å

  • V = 1538.8 (7) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 7.87 mm−1

  • T = 293 K

  • 0.03 × 0.02 × 0.02 mm
Data collection

  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2004[Sheldrick, G. M. (2004). SADABS. University of Göttingen, Germany.]) Tmin = 0.244, Tmax = 0.332

  • 13143 measured reflections

  • 3841 independent reflections

  • 2910 reflections with I > 2σ(I)

  • Rint = 0.046
Refinement

  • R[F2 > 2σ(F2)] = 0.034

  • wR(F2) = 0.066

  • S = 0.96

  • 3841 reflections

  • 199 parameters

  • H-atom parameters constrained

  • Δρmax = 0.44 e Å−3

  • Δρmin = −0.44 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1553 Friedel pairs

  • Flack parameter: 0.004 (13)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O1—H1⋯N1 0.82 1.85 2.561 (4) 144

Data collection: APEX2 (Bruker, 2006[Bruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2006[Bruker (2006). APEX2 and SAINT. Bruker AXS 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: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536813018977/is5290sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813018977/is5290Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813018977/is5290Isup3.cml

checkCIF report


Comment top

It has been known for many years that the azo compounds are a widely used class of dyes due to their application in various fields such as the dyeing of textile fibers, the coloring of different materials, colored plastics and electrochemical sensors (Gale et al., 1998). Azo dyes are synthetic colours that contain an azo group, as part of the structure. They are characterized by the azo linkage (–N=N–). Azo groups do not occur naturally. Many azo compounds have been synthesized by the diazotization and diazo coupling reaction (Wang et al., 2003), which entails an electrophilic substitution reaction where an aryl diazonium-cation attacks another aryl ring, since diazonium salts are often unstable near room temperature; the azo coupling reactions are typically conducted near ice temperature.

The pH of solution is quite important; it must be mildly acidic or neutral, since no reaction takes place if the pH is too low (Heinrich et al., 2007). We report herein the crystal structure of the title compound (Fig. 1), obtained through the diazotization of 2,4,6-tribromoaniline followed by a coupling reaction with 2-naphthol. In the molecule of the title compound, all bond lengths are in good agreement with those reported for other azo compounds (Deveci et al., 2005; El-Ghamry et al., 2008). The bond lengths and angles are within normal ranges. The naphthalene ring system is oriented at a dihedral angle of 33.80 (16)° with respect to the benzene ring. In the crystal, molecules are packed into columns along the a axis by π–π interactions between adjacent molecules with the closest approach between centroids of aromatic rings being 3.815 (3) Å (Fig. 2).

Related literature top

For applications of azo compounds, see: Gale et al. (1998). For the synthesis of similar compounds, see: Wang et al. (2003); Heinrich et al. (2007). For bond lengths and angles in related azo compounds, see: Deveci et al. (2005); El-Ghamry et al. (2008).

Experimental top

The title compound was prepared by the previously reported method in the literature; following the classical method of synthesis of other aromatic azo-compounds, diazotization of 2,4,6-tribromoaniline followed by a coupling reaction with 2-naphthol (Wang et al., 2003). This gives a red powder which was crystallized from methanol solution leading to red prismatic crystals.

Refinement top

All H atoms have been placed in geometrically idealized positions (C—H = 0.93 Å and O—H = 0.82 Å) and refined as riding with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(O).

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with atom labels and 50% probability displacement ellipsoids for non-H atoms. The dashed line indicates the O—H···N hydrogen bond.
[Figure 2] Fig. 2. A packing diagram of the title compound viewed along the a axis.
(E)-1-[(2,4,6-Tribromophenyl)diazenyl]naphthalen-2-ol top
Crystal data top
C16H9Br3N2ODx = 2.093 Mg m−3
Mr = 484.98Melting point: 422 K
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 2052 reflections
a = 3.9904 (11) Åθ = 3.1–28.6°
b = 15.689 (4) ŵ = 7.87 mm−1
c = 24.580 (7) ÅT = 293 K
V = 1538.8 (7) Å3Prism, red
Z = 40.03 × 0.02 × 0.02 mm
F(000) = 928
Data collection top
Bruker APEXII CCD
diffractometer		3841 independent reflections
Radiation source: fine-focus sealed tube2910 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.046
ϕ and ω scansθmax = 28.3°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)		h = −5→5
Tmin = 0.244, Tmax = 0.332k = −20→20
13143 measured reflectionsl = −32→32
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.034H-atom parameters constrained
wR(F2) = 0.066 w = 1/[σ2(Fo2) + (0.0241P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.96(Δ/σ)max < 0.001
3841 reflectionsΔρmax = 0.44 e Å−3
199 parametersΔρmin = −0.44 e Å−3
0 restraintsAbsolute structure: Flack (1983), 1553 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.004 (13)
Crystal data top
C16H9Br3N2OV = 1538.8 (7) Å3
Mr = 484.98Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 3.9904 (11) ŵ = 7.87 mm−1
b = 15.689 (4) ÅT = 293 K
c = 24.580 (7) Å0.03 × 0.02 × 0.02 mm
Data collection top
Bruker APEXII CCD
diffractometer		3841 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)		2910 reflections with I > 2σ(I)
Tmin = 0.244, Tmax = 0.332Rint = 0.046
13143 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.034H-atom parameters constrained
wR(F2) = 0.066Δρmax = 0.44 e Å−3
S = 0.96Δρmin = −0.44 e Å−3
3841 reflectionsAbsolute structure: Flack (1983), 1553 Friedel pairs
199 parametersAbsolute structure parameter: 0.004 (13)
0 restraints
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Br1−0.12633 (11)−0.15833 (2)0.00161 (2)0.0379 (1)
Br20.51026 (12)0.09227 (3)0.12476 (2)0.0481 (2)
Br30.12463 (15)0.17248 (3)−0.08940 (2)0.0557 (2)
O1−0.4121 (9)0.02557 (17)−0.18018 (11)0.0512 (10)
N1−0.0964 (9)−0.01183 (18)−0.09266 (12)0.0352 (10)
N2−0.0368 (8)−0.08820 (18)−0.10973 (11)0.0317 (10)
C10.0433 (10)0.0081 (2)−0.04134 (14)0.0304 (11)
C20.0607 (9)−0.0479 (2)0.00323 (14)0.0304 (11)
C30.2004 (11)−0.0226 (2)0.05163 (14)0.0333 (12)
C40.3199 (11)0.0592 (2)0.05766 (15)0.0342 (11)
C50.2983 (11)0.1171 (2)0.01563 (15)0.0373 (14)
C60.1572 (11)0.0906 (2)−0.03316 (14)0.0337 (11)
C7−0.1725 (10)−0.1097 (2)−0.15902 (14)0.0307 (11)
C8−0.3485 (12)−0.0537 (3)−0.19353 (15)0.0387 (14)
C9−0.4639 (11)−0.0836 (3)−0.24475 (15)0.0432 (15)
C10−0.4111 (11)−0.1653 (3)−0.25976 (14)0.0437 (15)
C11−0.2321 (11)−0.2247 (3)−0.22725 (14)0.0355 (11)
C12−0.1079 (10)−0.1969 (2)−0.17622 (14)0.0299 (11)
C130.0637 (11)−0.2558 (2)−0.14376 (15)0.0360 (14)
C140.1125 (12)−0.3377 (2)−0.16128 (16)0.0443 (14)
C15−0.0059 (13)−0.3643 (3)−0.21170 (17)0.0487 (16)
C16−0.1756 (13)−0.3094 (3)−0.24383 (16)0.0470 (16)
H1−0.334560.03546−0.149930.0768*
H30.21435−0.060780.080450.0402*
H50.376330.172590.019850.0449*
H9−0.57652−0.04673−0.268070.0520*
H10−0.49596−0.18353−0.293010.0524*
H130.14544−0.23913−0.109960.0432*
H140.22647−0.37609−0.139160.0531*
H150.03174−0.41991−0.223310.0588*
H16−0.25621−0.32774−0.277340.0563*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0446 (2)0.0286 (2)0.0405 (2)−0.0047 (2)0.0045 (2)0.0003 (2)
Br20.0505 (3)0.0582 (3)0.0356 (2)−0.0074 (2)−0.0023 (2)−0.0136 (2)
Br30.0867 (4)0.0324 (2)0.0481 (2)−0.0006 (3)0.0002 (3)0.0081 (2)
O10.072 (2)0.0408 (16)0.0409 (16)0.0086 (18)−0.0086 (17)0.0069 (13)
N10.045 (2)0.0281 (16)0.0324 (16)−0.0006 (16)0.0006 (17)−0.0034 (13)
N20.035 (2)0.0328 (16)0.0273 (14)−0.0046 (16)0.0039 (14)−0.0007 (13)
C10.031 (2)0.0277 (18)0.0324 (19)0.0023 (18)0.0052 (18)−0.0024 (15)
C20.031 (2)0.0263 (17)0.0339 (18)0.0023 (16)0.0058 (19)−0.0031 (16)
C30.036 (2)0.033 (2)0.031 (2)0.0011 (19)0.0048 (18)0.0007 (16)
C40.031 (2)0.041 (2)0.0306 (19)0.000 (2)0.0028 (19)−0.0106 (17)
C50.047 (3)0.028 (2)0.037 (2)−0.0053 (19)0.0080 (19)−0.0072 (16)
C60.042 (2)0.0272 (18)0.0318 (19)0.001 (2)0.0068 (19)0.0040 (16)
C70.033 (2)0.035 (2)0.0241 (18)−0.0030 (19)0.0019 (17)0.0007 (16)
C80.045 (3)0.036 (2)0.035 (2)−0.002 (2)0.001 (2)0.0053 (17)
C90.044 (3)0.056 (3)0.0297 (19)−0.002 (2)−0.005 (2)0.0108 (19)
C100.048 (3)0.059 (3)0.0240 (18)−0.013 (3)0.0018 (18)−0.0022 (19)
C110.037 (2)0.045 (2)0.0245 (19)−0.011 (2)0.0032 (18)−0.0023 (18)
C120.028 (2)0.0331 (19)0.0286 (18)−0.0085 (19)0.0068 (17)−0.0003 (15)
C130.040 (3)0.038 (2)0.0301 (19)−0.002 (2)0.0008 (18)−0.0044 (16)
C140.052 (3)0.036 (2)0.045 (2)0.005 (2)0.006 (2)−0.0030 (19)
C150.048 (3)0.041 (2)0.057 (3)−0.004 (2)0.013 (3)−0.015 (2)
C160.054 (3)0.053 (3)0.034 (2)−0.014 (2)0.006 (2)−0.016 (2)
Geometric parameters (Å, º) top
Br1—C21.887 (3)C9—C101.350 (7)
Br2—C41.889 (4)C10—C111.420 (6)
Br3—C61.892 (3)C11—C161.408 (7)
O1—C81.311 (5)C11—C121.418 (5)
O1—H10.8200C12—C131.400 (5)
N1—N21.292 (4)C13—C141.369 (5)
N1—C11.414 (5)C14—C151.390 (6)
N2—C71.369 (5)C15—C161.351 (7)
C1—C21.406 (5)C3—H30.9300
C1—C61.387 (5)C5—H50.9300
C2—C31.373 (5)C9—H90.9300
C3—C41.377 (5)C10—H100.9300
C4—C51.378 (5)C13—H130.9300
C5—C61.389 (5)C14—H140.9300
C7—C81.409 (6)C15—H150.9300
C7—C121.455 (5)C16—H160.9300
C8—C91.420 (6)
C8—O1—H1109.00C12—C11—C16119.4 (4)
N2—N1—C1115.0 (3)C10—C11—C12118.2 (4)
N1—N2—C7116.3 (3)C7—C12—C13122.8 (3)
N1—C1—C2125.2 (3)C11—C12—C13118.2 (3)
C2—C1—C6117.0 (3)C7—C12—C11119.0 (3)
N1—C1—C6117.7 (3)C12—C13—C14120.7 (3)
Br1—C2—C3116.4 (2)C13—C14—C15120.9 (4)
C1—C2—C3121.0 (3)C14—C15—C16120.0 (4)
Br1—C2—C1122.5 (3)C11—C16—C15120.9 (4)
C2—C3—C4120.2 (3)C2—C3—H3120.00
Br2—C4—C5119.9 (3)C4—C3—H3120.00
C3—C4—C5120.8 (3)C4—C5—H5121.00
Br2—C4—C3119.3 (3)C6—C5—H5121.00
C4—C5—C6118.4 (3)C8—C9—H9120.00
Br3—C6—C5117.1 (2)C10—C9—H9120.00
C1—C6—C5122.5 (3)C9—C10—H10118.00
Br3—C6—C1120.4 (3)C11—C10—H10118.00
N2—C7—C12114.8 (3)C12—C13—H13120.00
C8—C7—C12120.0 (3)C14—C13—H13120.00
N2—C7—C8125.2 (3)C13—C14—H14120.00
O1—C8—C9118.2 (4)C15—C14—H14120.00
C7—C8—C9119.3 (4)C14—C15—H15120.00
O1—C8—C7122.5 (3)C16—C15—H15120.00
C8—C9—C10120.3 (4)C11—C16—H16120.00
C9—C10—C11123.2 (4)C15—C16—H16120.00
C10—C11—C16122.5 (4)
C1—N1—N2—C7179.2 (3)C12—C7—C8—O1−179.7 (4)
N2—N1—C1—C2−38.6 (5)C12—C7—C8—C90.6 (6)
N2—N1—C1—C6144.9 (4)N2—C7—C12—C11−178.7 (3)
N1—N2—C7—C84.8 (6)N2—C7—C12—C133.3 (6)
N1—N2—C7—C12−178.4 (3)C8—C7—C12—C11−1.6 (6)
N1—C1—C2—Br1−3.5 (5)C8—C7—C12—C13−179.6 (4)
N1—C1—C2—C3−179.8 (4)O1—C8—C9—C10−178.5 (4)
C6—C1—C2—Br1173.1 (3)C7—C8—C9—C101.3 (7)
C6—C1—C2—C3−3.2 (6)C8—C9—C10—C11−2.1 (7)
N1—C1—C6—Br3−0.1 (5)C9—C10—C11—C121.0 (6)
N1—C1—C6—C5179.9 (4)C9—C10—C11—C16−179.2 (4)
C2—C1—C6—Br3−176.9 (3)C10—C11—C12—C70.9 (6)
C2—C1—C6—C53.1 (6)C10—C11—C12—C13179.0 (4)
Br1—C2—C3—C4−175.1 (3)C16—C11—C12—C7−179.0 (4)
C1—C2—C3—C41.4 (6)C16—C11—C12—C13−0.9 (6)
C2—C3—C4—Br2179.9 (3)C10—C11—C16—C15−179.6 (4)
C2—C3—C4—C50.7 (6)C12—C11—C16—C150.2 (7)
Br2—C4—C5—C6179.9 (3)C7—C12—C13—C14178.7 (4)
C3—C4—C5—C6−0.8 (6)C11—C12—C13—C140.7 (6)
C4—C5—C6—Br3178.9 (3)C12—C13—C14—C150.2 (7)
C4—C5—C6—C1−1.1 (6)C13—C14—C15—C16−0.9 (7)
N2—C7—C8—O1−3.0 (7)C14—C15—C16—C110.7 (7)
N2—C7—C8—C9177.3 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N10.821.852.561 (4)144

Experimental details

Crystal data
Chemical formulaC16H9Br3N2O
Mr484.98
Crystal system, space groupOrthorhombic, P212121
Temperature (K)293
a, b, c (Å)3.9904 (11), 15.689 (4), 24.580 (7)
V (Å3)1538.8 (7)
Z4
Radiation typeMo Kα
µ (mm−1)7.87
Crystal size (mm)0.03 × 0.02 × 0.02
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2004)
Tmin, Tmax0.244, 0.332
No. of measured, independent and
observed [I > 2σ(I)] reflections		13143, 3841, 2910
Rint0.046
(sin θ/λ)max (Å−1)0.667
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.034, 0.066, 0.96
No. of reflections3841
No. of parameters199
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.44, −0.44
Absolute structureFlack (1983), 1553 Friedel pairs
Absolute structure parameter0.004 (13)

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012), WinGX (Farrugia, 2012).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N10.821.852.561 (4)144
 

Acknowledgements

We thank all researchers of the CHEMS Research Unit, University of Constantine, Algeria, for their valuable assistance. Thanks are due to the MESRS (Ministère de l'Enseignement Supérieur et de la Recherche Scientifique – Algérie) for financial support. We also express our gratitude to Professor L. Ouahab, Director of Research at the Laboratory UMR LCSIM 6511, CNRS, Rennes I (France), for recording the diffraction data and help with the structure determination.

References

First citationBruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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ISSN: 2056-9890
Volume 69| Part 8| August 2013| Page o1250
doi:10.1107/S1600536813018977
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