organic compounds
4-[(4-Bromophenyl)diazenyl]-2-ethoxyaniline
aDepartment of Chemistry, Islamic Azad University, Karaj Branch, Karaj, Iran, and bFaculty of Chemistry, Tarbiat Moallem University, Tehran, Iran
*Correspondence e-mail: m.melardi@kiau.ac.ir
The title compound, C14H14BrN3O, exhibits a trans geometry about the –N=N– double bond. The dihedral angle between the benzene rings is 24.01 (5)°. An intramolecular N—H⋯O hydrogen bond occurs. In the crystal, intermolecular N—H⋯N hydrogen bonds between the amine groups lead to the formation of a C(8) polymeric chain along [101].
Related literature
For the synthesis and crystal structures of similar diazenyl compounds, see: de Wit et al. (2008); Yazici et al. (2006). For of a chloro analogue of the title compound, see: Rofouei et al. (2011). For graph-set motifs, see: Bernstein et al. (1995).
Experimental
Crystal data
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Refinement
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Data collection: SMART X2S (Bruker, 2009); cell SAINT (Bruker, 2009); data reduction: SAINT; 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.
Supporting information
https://doi.org/10.1107/S160053681104877X/pv2476sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S160053681104877X/pv2476Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S160053681104877X/pv2476Isup3.cml
To a 100 ml flask in an ice bath, was added (0.349 g, 2 mmol) p-boromoaniline and (3.65 g, 0.1 mol) of HCl (d = 1.18 g.ml-1). To the obtained solution, was added dropwise a solution of sodium nitrite (0.14 g in 5 ml H2O). Then, a diluted solution of o-ethoxyaniline (0.244 g, 2 mmol) in methanol (5 ml) was added to the above solution. The pH of the solution was adjusted at about 6–7 by adding a solution of 10% of sodium acetate. The solution was stirred for about an hour, giving an orange precipitate. It was then filtered off and dried in vacuum. After dissolving in diethylether and recrystallization, red crystals of the title compound were obtained. M.p. 373–376 K.
Hydrogen atoms bonded to carbon were included at geometrically idealized positions and refined in riding mode with distances H—C = 0.95, 0.98 and 0.99 Å for aryl, methyl and methylene type H-atoms, respectively with Uiso(H) set to 1.2(1.5 for methyl)Ueq(C). Hydrogen atoms bonded to N were located from a difference Fourier map and refined with the N—H distances restrained to 0.88 (1) Å and Uiso(H) = 1.2Ueq(N).
We have recenly reported the ═N—) commonly adopt the trans configuration in the ground state. In continuation to our work in this field, we now report the of the title compound.
of 4-[(4-chlorophenyl)diazenyl]-3-methoxyaniline (Rofouei et al., 2011), a chloro analogue of the title compound. Diazenyl compounds characterized by having a diazo group (—NThe title molecule (Fig. 1) adopts a trans configuration about the –N1═N2– double bond and the C1—N1—N2—C9 dihedral angle is 177.3 (4)°. The molecular dimensions in the title compound are similar to the corresponding dimensions reported in other (Yazici et al., 2006; de Wit et al., 2008; Rofouei et al., 2011).
In the structure of the title compound, the molecules are linked into chain-like polymers along the c axis, with C(8) graph set motif (Bernstein et al., 1995), through N3—H3A···N2i hydrogen bonds with D···A separation of 3.228 (6) Å (Fig. 2 and Tab. 1). The structure is further consolidated by N3—H3A···O1 intramolecular hydrogen bond with D···A separation of 2.628 (5) Å.
For the synthesis and crystal structures of similar diazenyl compounds, see: de Wit et al. (2008); Yazici et al. (2006). For
of a chloro analogue of the title compound, see: Rofouei et al. (2011). For graph-set motifs, see: Bernstein et al. (1995).Data collection: SMART X2S (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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).C14H14BrN3O | F(000) = 648 |
Mr = 320.19 | Dx = 1.540 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 2935 reflections |
a = 13.219 (2) Å | θ = 2.9–24.8° |
b = 8.8289 (17) Å | µ = 2.97 mm−1 |
c = 13.506 (2) Å | T = 200 K |
β = 118.855 (6)° | Block, yellow |
V = 1380.6 (4) Å3 | 0.40 × 0.20 × 0.10 mm |
Z = 4 |
Bruker SMART X2S benchtop diffractometer | 2408 independent reflections |
Radiation source: fine-focus sealed tube | 1775 reflections with I > 2Σ(I) |
Graphite monochromator | Rint = 0.075 |
Detector resolution: 8.33 pixels mm-1 | θmax = 25.0°, θmin = 1.8° |
ω scans | h = −15→13 |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | k = −10→10 |
Tmin = 0.383, Tmax = 0.755 | l = −16→16 |
8299 measured reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.065 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.198 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | w = 1/[σ2(Fo2) + (0.1373P)2] where P = (Fo2 + 2Fc2)/3 |
2408 reflections | (Δ/σ)max < 0.001 |
178 parameters | Δρmax = 0.98 e Å−3 |
2 restraints | Δρmin = −1.11 e Å−3 |
C14H14BrN3O | V = 1380.6 (4) Å3 |
Mr = 320.19 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 13.219 (2) Å | µ = 2.97 mm−1 |
b = 8.8289 (17) Å | T = 200 K |
c = 13.506 (2) Å | 0.40 × 0.20 × 0.10 mm |
β = 118.855 (6)° |
Bruker SMART X2S benchtop diffractometer | 2408 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 1775 reflections with I > 2Σ(I) |
Tmin = 0.383, Tmax = 0.755 | Rint = 0.075 |
8299 measured reflections |
R[F2 > 2σ(F2)] = 0.065 | 2 restraints |
wR(F2) = 0.198 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | Δρmax = 0.98 e Å−3 |
2408 reflections | Δρmin = −1.11 e Å−3 |
178 parameters |
Experimental. 1H NMR (300 MHz, d6-DMSO): 1.31 (3H, CH3), 4.10 (2H, OCH2), 6.72–7.68 (7H, aromatic ring) and 5.87 (2H, NH2 groups). 13C NMR (100 MHz, DMSO): 14.63 (CH3), 63.44 (OCH2), 101.60–151.34 (C atoms of aromatic rings). |
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. |
x | y | z | Uiso*/Ueq | ||
Br1 | 0.62107 (6) | 0.84573 (8) | 0.08362 (5) | 0.0740 (4) | |
O1 | −0.1368 (3) | 0.1305 (4) | −0.0555 (3) | 0.0469 (9) | |
N1 | 0.1207 (4) | 0.4681 (5) | −0.1255 (3) | 0.0441 (10) | |
N2 | 0.1867 (4) | 0.4891 (4) | −0.0227 (3) | 0.0444 (10) | |
N3 | −0.2711 (4) | 0.1068 (5) | −0.2750 (4) | 0.0477 (11) | |
H3A | −0.296 (5) | 0.071 (6) | −0.343 (2) | 0.057* | |
H3B | −0.270 (5) | 0.039 (5) | −0.227 (3) | 0.057* | |
C1 | 0.0220 (4) | 0.3782 (5) | −0.1537 (4) | 0.0380 (11) | |
C2 | −0.0054 (4) | 0.3036 (5) | −0.0774 (4) | 0.0396 (11) | |
H2 | 0.0424 | 0.3161 | 0.0018 | 0.047* | |
C3 | −0.1012 (4) | 0.2134 (5) | −0.1179 (4) | 0.0364 (11) | |
C4 | −0.1750 (4) | 0.1953 (5) | −0.2364 (4) | 0.0368 (11) | |
C5 | −0.1446 (4) | 0.2697 (5) | −0.3088 (4) | 0.0399 (11) | |
H5 | −0.1917 | 0.2580 | −0.3881 | 0.048* | |
C6 | −0.0488 (5) | 0.3591 (5) | −0.2688 (4) | 0.0438 (13) | |
H6 | −0.0305 | 0.4089 | −0.3205 | 0.053* | |
C7 | −0.0682 (5) | 0.1345 (6) | 0.0658 (4) | 0.0454 (13) | |
H7A | −0.0598 | 0.2399 | 0.0937 | 0.054* | |
H7B | 0.0096 | 0.0923 | 0.0900 | 0.054* | |
C8 | −0.1313 (5) | 0.0403 (7) | 0.1108 (4) | 0.0601 (15) | |
H8A | −0.0876 | 0.0388 | 0.1936 | 0.090* | |
H8B | −0.1396 | −0.0633 | 0.0818 | 0.090* | |
H8C | −0.2079 | 0.0839 | 0.0864 | 0.090* | |
C9 | 0.2870 (4) | 0.5761 (5) | −0.0032 (4) | 0.0429 (12) | |
C10 | 0.3484 (5) | 0.6451 (5) | 0.0999 (4) | 0.0472 (13) | |
H10 | 0.3240 | 0.6346 | 0.1552 | 0.057* | |
C11 | 0.4442 (4) | 0.7285 (6) | 0.1237 (4) | 0.0461 (12) | |
H11 | 0.4841 | 0.7798 | 0.1940 | 0.055* | |
C12 | 0.4832 (4) | 0.7385 (6) | 0.0462 (4) | 0.0479 (13) | |
C13 | 0.4241 (6) | 0.6680 (7) | −0.0578 (5) | 0.0611 (17) | |
H13 | 0.4510 | 0.6746 | −0.1115 | 0.073* | |
C14 | 0.3252 (5) | 0.5878 (7) | −0.0819 (4) | 0.0566 (15) | |
H14 | 0.2829 | 0.5401 | −0.1534 | 0.068* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Br1 | 0.0634 (5) | 0.0968 (6) | 0.0643 (5) | −0.0445 (4) | 0.0328 (4) | −0.0213 (3) |
O1 | 0.043 (2) | 0.060 (2) | 0.0371 (17) | −0.0123 (17) | 0.0188 (17) | −0.0022 (15) |
N1 | 0.046 (3) | 0.043 (2) | 0.040 (2) | −0.0016 (19) | 0.018 (2) | 0.0031 (17) |
N2 | 0.049 (3) | 0.043 (2) | 0.043 (2) | 0.0051 (19) | 0.024 (2) | 0.0064 (18) |
N3 | 0.045 (3) | 0.055 (3) | 0.041 (2) | −0.014 (2) | 0.019 (2) | −0.0120 (19) |
C1 | 0.034 (3) | 0.037 (2) | 0.044 (3) | −0.002 (2) | 0.020 (2) | −0.0029 (19) |
C2 | 0.031 (3) | 0.043 (2) | 0.039 (2) | 0.000 (2) | 0.012 (2) | −0.001 (2) |
C3 | 0.031 (3) | 0.038 (2) | 0.042 (3) | 0.001 (2) | 0.019 (2) | −0.002 (2) |
C4 | 0.032 (3) | 0.035 (2) | 0.043 (3) | 0.001 (2) | 0.018 (2) | −0.0042 (19) |
C5 | 0.041 (3) | 0.043 (3) | 0.037 (3) | −0.001 (2) | 0.020 (2) | −0.005 (2) |
C6 | 0.055 (3) | 0.036 (2) | 0.049 (3) | 0.000 (2) | 0.031 (3) | −0.002 (2) |
C7 | 0.049 (3) | 0.049 (3) | 0.037 (3) | −0.001 (2) | 0.019 (2) | −0.001 (2) |
C8 | 0.068 (4) | 0.060 (3) | 0.050 (3) | −0.010 (3) | 0.028 (3) | 0.005 (3) |
C9 | 0.044 (3) | 0.043 (3) | 0.045 (3) | 0.000 (2) | 0.023 (2) | 0.005 (2) |
C10 | 0.050 (3) | 0.049 (3) | 0.046 (3) | −0.004 (2) | 0.025 (3) | 0.002 (2) |
C11 | 0.049 (3) | 0.047 (3) | 0.036 (3) | −0.004 (2) | 0.017 (2) | 0.000 (2) |
C12 | 0.040 (3) | 0.054 (3) | 0.046 (3) | −0.012 (2) | 0.018 (2) | 0.001 (2) |
C13 | 0.062 (4) | 0.081 (4) | 0.050 (3) | −0.034 (3) | 0.035 (3) | −0.016 (3) |
C14 | 0.050 (3) | 0.068 (4) | 0.043 (3) | −0.014 (3) | 0.015 (3) | −0.010 (3) |
Br1—C12 | 1.893 (5) | C6—H6 | 0.9500 |
O1—C3 | 1.361 (6) | C7—C8 | 1.498 (8) |
O1—C7 | 1.439 (6) | C7—H7A | 0.9900 |
N1—N2 | 1.246 (5) | C7—H7B | 0.9900 |
N1—C1 | 1.412 (6) | C8—H8A | 0.9800 |
N2—C9 | 1.442 (7) | C8—H8B | 0.9800 |
N3—C4 | 1.363 (7) | C8—H8C | 0.9800 |
N3—H3A | 0.876 (10) | C9—C10 | 1.371 (7) |
N3—H3B | 0.879 (10) | C9—C14 | 1.383 (8) |
C1—C6 | 1.384 (7) | C10—C11 | 1.363 (7) |
C1—C2 | 1.410 (7) | C10—H10 | 0.9500 |
C2—C3 | 1.367 (7) | C11—C12 | 1.375 (7) |
C2—H2 | 0.9500 | C11—H11 | 0.9500 |
C3—C4 | 1.424 (7) | C12—C13 | 1.383 (7) |
C4—C5 | 1.388 (7) | C13—C14 | 1.380 (9) |
C5—C6 | 1.363 (7) | C13—H13 | 0.9500 |
C5—H5 | 0.9500 | C14—H14 | 0.9500 |
C3—O1—C7 | 118.4 (4) | O1—C7—H7B | 110.5 |
N2—N1—C1 | 116.3 (4) | C8—C7—H7B | 110.5 |
N1—N2—C9 | 111.8 (4) | H7A—C7—H7B | 108.7 |
C4—N3—H3A | 114 (4) | C7—C8—H8A | 109.5 |
C4—N3—H3B | 116 (4) | C7—C8—H8B | 109.5 |
H3A—N3—H3B | 113 (5) | H8A—C8—H8B | 109.5 |
C6—C1—C2 | 119.4 (4) | C7—C8—H8C | 109.5 |
C6—C1—N1 | 114.1 (4) | H8A—C8—H8C | 109.5 |
C2—C1—N1 | 126.5 (4) | H8B—C8—H8C | 109.5 |
C3—C2—C1 | 119.6 (4) | C10—C9—C14 | 119.4 (5) |
C3—C2—H2 | 120.2 | C10—C9—N2 | 117.6 (5) |
C1—C2—H2 | 120.2 | C14—C9—N2 | 123.0 (5) |
O1—C3—C2 | 126.5 (4) | C11—C10—C9 | 120.4 (5) |
O1—C3—C4 | 112.5 (4) | C11—C10—H10 | 119.8 |
C2—C3—C4 | 121.0 (4) | C9—C10—H10 | 119.8 |
N3—C4—C5 | 122.3 (4) | C10—C11—C12 | 120.2 (5) |
N3—C4—C3 | 120.0 (4) | C10—C11—H11 | 119.9 |
C5—C4—C3 | 117.7 (4) | C12—C11—H11 | 119.9 |
C6—C5—C4 | 121.6 (4) | C11—C12—C13 | 120.6 (5) |
C6—C5—H5 | 119.2 | C11—C12—Br1 | 119.7 (4) |
C4—C5—H5 | 119.2 | C13—C12—Br1 | 119.7 (4) |
C5—C6—C1 | 120.8 (5) | C14—C13—C12 | 118.4 (5) |
C5—C6—H6 | 119.6 | C14—C13—H13 | 120.8 |
C1—C6—H6 | 119.6 | C12—C13—H13 | 120.8 |
O1—C7—C8 | 106.3 (4) | C13—C14—C9 | 120.9 (5) |
O1—C7—H7A | 110.5 | C13—C14—H14 | 119.6 |
C8—C7—H7A | 110.5 | C9—C14—H14 | 119.6 |
C1—N1—N2—C9 | 177.3 (4) | C2—C1—C6—C5 | 0.2 (7) |
N2—N1—C1—C6 | 179.6 (4) | N1—C1—C6—C5 | 177.1 (4) |
N2—N1—C1—C2 | −3.8 (7) | C3—O1—C7—C8 | 177.1 (5) |
C6—C1—C2—C3 | 0.2 (7) | N1—N2—C9—C10 | 161.2 (5) |
N1—C1—C2—C3 | −176.3 (5) | N1—N2—C9—C14 | −21.2 (7) |
C7—O1—C3—C2 | −0.6 (7) | C14—C9—C10—C11 | 2.1 (8) |
C7—O1—C3—C4 | 178.2 (4) | N2—C9—C10—C11 | 179.8 (4) |
C1—C2—C3—O1 | 177.6 (5) | C9—C10—C11—C12 | −3.0 (8) |
C1—C2—C3—C4 | −1.0 (7) | C10—C11—C12—C13 | 1.9 (9) |
O1—C3—C4—N3 | 2.2 (6) | C10—C11—C12—Br1 | −176.6 (4) |
C2—C3—C4—N3 | −178.9 (5) | C11—C12—C13—C14 | 0.1 (10) |
O1—C3—C4—C5 | −177.4 (4) | Br1—C12—C13—C14 | 178.6 (5) |
C2—C3—C4—C5 | 1.5 (7) | C12—C13—C14—C9 | −1.0 (10) |
N3—C4—C5—C6 | 179.3 (5) | C10—C9—C14—C13 | −0.1 (9) |
C3—C4—C5—C6 | −1.1 (7) | N2—C9—C14—C13 | −177.6 (6) |
C4—C5—C6—C1 | 0.3 (8) |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3A···N2i | 0.88 (1) | 2.38 (2) | 3.228 (6) | 163 (5) |
N3—H3B···O1 | 0.88 (1) | 2.28 (5) | 2.628 (5) | 103 (4) |
Symmetry code: (i) x−1/2, −y+1/2, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | C14H14BrN3O |
Mr | 320.19 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 200 |
a, b, c (Å) | 13.219 (2), 8.8289 (17), 13.506 (2) |
β (°) | 118.855 (6) |
V (Å3) | 1380.6 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 2.97 |
Crystal size (mm) | 0.40 × 0.20 × 0.10 |
Data collection | |
Diffractometer | Bruker SMART X2S benchtop |
Absorption correction | Multi-scan (SADABS; Bruker, 2009) |
Tmin, Tmax | 0.383, 0.755 |
No. of measured, independent and observed [I > 2Σ(I)] reflections | 8299, 2408, 1775 |
Rint | 0.075 |
(sin θ/λ)max (Å−1) | 0.594 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.065, 0.198, 1.00 |
No. of reflections | 2408 |
No. of parameters | 178 |
No. of restraints | 2 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.98, −1.11 |
Computer programs: SMART X2S (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3A···N2i | 0.876 (10) | 2.38 (2) | 3.228 (6) | 163 (5) |
N3—H3B···O1 | 0.879 (10) | 2.28 (5) | 2.628 (5) | 103 (4) |
Symmetry code: (i) x−1/2, −y+1/2, z−1/2. |
Acknowledgements
JAG thanks the American Crystallographic Association for a scholarship to the ACA summer school, and Bruce C. Noll of Bruker AXS Inc., and Peter Müller of the Massachusetts Institute of Technology for their assistance in this work.
References
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We have recenly reported the crystal structure of 4-[(4-chlorophenyl)diazenyl]-3-methoxyaniline (Rofouei et al., 2011), a chloro analogue of the title compound. Diazenyl compounds characterized by having a diazo group (—N═N—) commonly adopt the trans configuration in the ground state. In continuation to our work in this field, we now report the crystal structure of the title compound.
The title molecule (Fig. 1) adopts a trans configuration about the –N1═N2– double bond and the C1—N1—N2—C9 dihedral angle is 177.3 (4)°. The molecular dimensions in the title compound are similar to the corresponding dimensions reported in other azo compounds (Yazici et al., 2006; de Wit et al., 2008; Rofouei et al., 2011).
In the structure of the title compound, the molecules are linked into chain-like polymers along the c axis, with C(8) graph set motif (Bernstein et al., 1995), through N3—H3A···N2i hydrogen bonds with D···A separation of 3.228 (6) Å (Fig. 2 and Tab. 1). The structure is further consolidated by N3—H3A···O1 intramolecular hydrogen bond with D···A separation of 2.628 (5) Å.