Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270103012125/fg1694sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270103012125/fg1694Isup2.hkl |
CCDC reference: 219565
4-Nitroaniline (21.5 g, 155 mmol) was dissolved in glacial acetic acid (40 ml) and cooled below room temperature. A sodium nitrite solution (5.4 g, 78 mmol) in water (100 ml) was added slowly, with continuous stirring. The yellow reaction mixture was then neutralized with an aqueous solution (10%) of NaHCO3, and a yellow precipitate was observed. The yellow crude product was isolated by filtration and dried over P2O5 under vacuum, and the product was recrystallized from a tetrahydrofurane/n-hexane mixture (1:1). Yellow column-shaped crystals suitable for X-ray analysis were obtained by slow evaporation of the solvent mixture (yield 15.1 g, 67.5%; m.p. 506 K).
The positional parameters of the H atoms were obtained geometrically, the C—H and N—H distances were fixed (0.93 Å for Csp2 and 0.86 Å for Nsp2 H atoms), and the atoms were refined as riding on their respective C and N atoms, with Uiso values of 1.2 times the Ueq value of the attached Csp2 and Nsp2 atoms. The nitro atoms show a large thermal motion, as indicated by their elongated displacement ellipsoids (Fig. 1). Split peaks for these atoms were not observed and consequently a disorder model was not used.
Data collection: CAD-4 EXPRESS (Enraf Nonius, 1994); cell refinement: CAD-4 EXPRESS (Enraf Nonius, 1994); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997), PLATON (Spek 2003); software used to prepare material for publication: WinGX publication routines (Farrugia, 1999).
C12H9N5O4 | F(000) = 592 |
Mr = 287.24 | Dx = 1.478 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 25 reflections |
a = 13.452 (1) Å | θ = 2.1–25.4° |
b = 13.671 (2) Å | µ = 0.12 mm−1 |
c = 7.034 (2) Å | T = 293 K |
β = 93.442 (11)° | Column, yellow |
V = 1291.2 (4) Å3 | 0.30 × 0.20 × 0.10 mm |
Z = 4 |
Enraf–Nonius CAD-4 diffractometer | θmax = 25.4°, θmin = 2.1° |
Graphite monochromator | h = −16→16 |
θ/2θ scans | k = 0→16 |
2581 measured reflections | l = 0→8 |
2375 independent reflections | 3 standard reflections every 60 min |
1405 reflections with I > 2σ(I) | intensity decay: 1% |
Rint = 0.017 |
Refinement on F2 | H-atom parameters constrained |
Least-squares matrix: full | w = 1/[σ2(Fo2) + (0.0647P)2 + 0.0938P] where P = (Fo2 + 2Fc2)/3 |
R[F2 > 2σ(F2)] = 0.038 | (Δ/σ)max < 0.001 |
wR(F2) = 0.124 | Δρmax = 0.18 e Å−3 |
S = 0.98 | Δρmin = −0.16 e Å−3 |
2375 reflections | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
191 parameters | Extinction coefficient: 0.015 (2) |
0 restraints |
C12H9N5O4 | V = 1291.2 (4) Å3 |
Mr = 287.24 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 13.452 (1) Å | µ = 0.12 mm−1 |
b = 13.671 (2) Å | T = 293 K |
c = 7.034 (2) Å | 0.30 × 0.20 × 0.10 mm |
β = 93.442 (11)° |
Enraf–Nonius CAD-4 diffractometer | Rint = 0.017 |
2581 measured reflections | 3 standard reflections every 60 min |
2375 independent reflections | intensity decay: 1% |
1405 reflections with I > 2σ(I) |
R[F2 > 2σ(F2)] = 0.038 | 0 restraints |
wR(F2) = 0.124 | H-atom parameters constrained |
S = 0.98 | Δρmax = 0.18 e Å−3 |
2375 reflections | Δρmin = −0.16 e Å−3 |
191 parameters |
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. Mean-plane data from final SHELXL refinemente run:- Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane) − 6.7348 (0.0165) x − 0.4055 (0.0546) y + 6.2859 (0.0050) z = 1.1593 (0.0172) * 0.0000 (0.0000) O11 * 0.0000 (0.0000) N1 * 0.0000 (0.0000) O12 Rms deviation of fitted atoms = 0.0000 − 8.1515 (0.0092) x − 0.2871 (0.0124) y + 5.8393 (0.0037) z = 0.4044 (0.0080) Angle to previous plane (with approximate e.s.d.) = 7.27 (0.14) * 0.0011 (0.0013) C11 * 0.0039 (0.0014) C12 * −0.0041 (0.0014) C13 * −0.0007 (0.0014) C14 * 0.0057 (0.0015) C15 * −0.0059 (0.0014) C16 Rms deviation of fitted atoms = 0.0041 − 6.9927 (0.0142) x − 0.8449 (0.0171) y + 6.2019 (0.0046) z = 0.6824 (0.0161) Angle to previous plane (with approximate e.s.d.) = 6.36 (0.13) * −0.0062 (0.0005) H11 * 0.0096 (0.0007) N11 * −0.0074 (0.0005) N12 * 0.0040 (0.0003) N13 Rms deviation of fitted atoms = 0.0071 − 7.0902 (0.0102) x + 0.0405 (0.0123) y + 6.1894 (0.0034) z = 1.4255 (0.0121) Angle to previous plane (with approximate e.s.d.) = 3.74 (0.13) * −0.0054 (0.0014) C21 * 0.0007 (0.0015) C22 * 0.0044 (0.0015) C23 * −0.0049 (0.0014) C24 * 0.0001 (0.0014) C25 * 0.0050 (0.0014) C26 Rms deviation of fitted atoms = 0.0041 − 6.2152 (0.0390) x + 1.8988 (0.0408) y + 6.3452 (0.0125) z = 3.4102 (0.0420) Angle to previous plane (with approximate e.s.d.) = 8.77 (0.29) * 0.0000 (0.0000) O21 * 0.0000 (0.0000) N2 * 0.0000 (0.0000) O22 Rms deviation of fitted atoms = 0.0000 − 7.1427 (0.0049) x − 0.4798 (0.0027) y + 6.1689 (0.0022) z = 0.9011 (0.0036) Angle to previous plane (with approximate e.s.d.) = 10.87 (0.28) * 0.0597 (0.0018) O11 * 0.0184 (0.0017) N1 * −0.0154 (0.0018) O12 * −0.0305 (0.0019) C11 * 0.0904 (0.0018) C12 * 0.0991 (0.0019) C13 * 0.0003 (0.0019) C14 * −0.1107 (0.0020) C15 * −0.1397 (0.0020) C16 * −0.0371 (0.0014) N11 * −0.0515 (0.0013) H11 * −0.0210 (0.0016) N12 * 0.0209 (0.0016) N13 * 0.0396 (0.0019) C21 * 0.0736 (0.0020) C22 * 0.0515 (0.0019) C23 * −0.0106 (0.0018) C24 * −0.0338 (0.0019) C25 * −0.0030 (0.0018) C26 Rms deviation of fitted atoms = 0.0610 − 8.1515 (0.0092) x − 0.2871 (0.0124) y + 5.8393 (0.0037) z = 0.4044 (0.0080) Angle to previous plane (with approximate e.s.d.) = 5.27 (0.08) * 0.0011 (0.0013) C11 * 0.0039 (0.0014) C12 * −0.0041 (0.0014) C13 * −0.0007 (0.0014) C14 * 0.0057 (0.0015) C15 * −0.0059 (0.0014) C16 Rms deviation of fitted atoms = 0.0041 − 7.0902 (0.0102) x + 0.0405 (0.0123) y + 6.1894 (0.0034) z = 1.4255 (0.0121) Angle to previous plane (with approximate e.s.d.) = 5.67 (0.11) * −0.0054 (0.0014) C21 * 0.0007 (0.0015) C22 * 0.0044 (0.0015) C23 * −0.0049 (0.0014) C24 * 0.0001 (0.0014) C25 * 0.0050 (0.0014) C26 Rms deviation of fitted atoms = 0.0041 Hydrogen bonds with H.·A < r(A) + 2.000 Angstroms and <DHA > 110 °. D—H d(D—H) d(H.·A) <DHA d(D.·A) A N11—H11 0.86 2.11 159 2.929 (2) O12 [−x + 1, y + 1/2, −z + 3/2] |
x | y | z | Uiso*/Ueq | ||
O12 | 0.43782 (12) | 0.22721 (11) | 0.6682 (3) | 0.0800 (6) | |
O11 | 0.29617 (13) | 0.23236 (11) | 0.5167 (3) | 0.0851 (6) | |
O22 | 0.02435 (16) | 1.14876 (15) | 0.2175 (3) | 0.1060 (8) | |
O21 | −0.06985 (12) | 1.02428 (15) | 0.1625 (3) | 0.0825 (6) | |
N11 | 0.37270 (12) | 0.68066 (11) | 0.6245 (2) | 0.0444 (4) | |
H11 | 0.4225 | 0.7100 | 0.6821 | 0.053* | |
N12 | 0.29723 (12) | 0.73297 (11) | 0.5438 (2) | 0.0430 (4) | |
N13 | 0.30850 (11) | 0.82373 (12) | 0.5707 (2) | 0.0439 (4) | |
N1 | 0.36748 (14) | 0.27316 (12) | 0.5958 (3) | 0.0553 (5) | |
N2 | 0.00714 (15) | 1.06165 (18) | 0.2267 (3) | 0.0646 (6) | |
C11 | 0.37069 (13) | 0.57963 (13) | 0.6154 (3) | 0.0386 (5) | |
C12 | 0.44457 (13) | 0.52635 (14) | 0.7164 (3) | 0.0425 (5) | |
H12 | 0.4944 | 0.5589 | 0.7888 | 0.051* | |
C13 | 0.44430 (14) | 0.42656 (15) | 0.7097 (3) | 0.0447 (5) | |
H13 | 0.4939 | 0.3908 | 0.7760 | 0.054* | |
C14 | 0.36885 (14) | 0.37937 (13) | 0.6027 (3) | 0.0428 (5) | |
C15 | 0.29484 (15) | 0.43071 (15) | 0.5030 (3) | 0.0460 (5) | |
H15 | 0.2445 | 0.3975 | 0.4332 | 0.055* | |
C16 | 0.29546 (14) | 0.53064 (14) | 0.5068 (3) | 0.0440 (5) | |
H16 | 0.2463 | 0.5659 | 0.4378 | 0.053* | |
C21 | 0.22772 (14) | 0.87928 (14) | 0.4845 (3) | 0.0408 (5) | |
C22 | 0.14358 (15) | 0.83812 (16) | 0.3894 (3) | 0.0512 (6) | |
H22 | 0.1365 | 0.7705 | 0.3821 | 0.061* | |
C23 | 0.07145 (15) | 0.89813 (17) | 0.3070 (3) | 0.0542 (6) | |
H23 | 0.0150 | 0.8717 | 0.2439 | 0.065* | |
C24 | 0.08370 (14) | 0.99785 (16) | 0.3189 (3) | 0.0475 (5) | |
C25 | 0.16511 (15) | 1.04029 (14) | 0.4127 (3) | 0.0482 (5) | |
H25 | 0.1714 | 1.1080 | 0.4195 | 0.058* | |
C26 | 0.23734 (14) | 0.97985 (15) | 0.4966 (3) | 0.0435 (5) | |
H26 | 0.2929 | 1.0070 | 0.5617 | 0.052* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O12 | 0.0732 (11) | 0.0411 (9) | 0.1204 (15) | 0.0125 (8) | −0.0379 (10) | 0.0021 (9) |
O11 | 0.0788 (12) | 0.0477 (10) | 0.1234 (16) | −0.0128 (9) | −0.0386 (11) | −0.0085 (10) |
O22 | 0.1082 (16) | 0.0673 (13) | 0.1374 (19) | 0.0282 (12) | −0.0355 (14) | 0.0193 (13) |
O21 | 0.0473 (10) | 0.1146 (16) | 0.0835 (13) | 0.0179 (10) | −0.0142 (9) | 0.0088 (11) |
N11 | 0.0406 (9) | 0.0370 (10) | 0.0542 (10) | 0.0024 (7) | −0.0093 (7) | 0.0014 (8) |
N12 | 0.0439 (9) | 0.0387 (10) | 0.0460 (10) | 0.0031 (8) | −0.0008 (7) | 0.0020 (8) |
N13 | 0.0439 (10) | 0.0354 (9) | 0.0516 (11) | 0.0017 (7) | −0.0045 (8) | 0.0030 (8) |
N1 | 0.0564 (11) | 0.0379 (10) | 0.0694 (13) | −0.0015 (9) | −0.0141 (10) | −0.0017 (9) |
N2 | 0.0568 (12) | 0.0772 (15) | 0.0589 (13) | 0.0210 (12) | −0.0052 (10) | 0.0070 (11) |
C11 | 0.0370 (10) | 0.0367 (11) | 0.0418 (11) | 0.0008 (9) | 0.0005 (9) | 0.0017 (9) |
C12 | 0.0381 (10) | 0.0389 (11) | 0.0492 (12) | −0.0024 (8) | −0.0086 (9) | −0.0004 (9) |
C13 | 0.0399 (11) | 0.0416 (12) | 0.0513 (13) | 0.0041 (9) | −0.0085 (9) | 0.0035 (10) |
C14 | 0.0425 (11) | 0.0355 (10) | 0.0498 (12) | 0.0008 (9) | −0.0027 (9) | −0.0005 (9) |
C15 | 0.0417 (11) | 0.0437 (11) | 0.0508 (13) | −0.0030 (10) | −0.0127 (9) | −0.0013 (10) |
C16 | 0.0418 (11) | 0.0416 (12) | 0.0469 (12) | 0.0051 (9) | −0.0104 (9) | 0.0042 (9) |
C21 | 0.0382 (10) | 0.0398 (11) | 0.0441 (11) | 0.0036 (8) | 0.0006 (9) | 0.0020 (9) |
C22 | 0.0475 (12) | 0.0395 (11) | 0.0655 (14) | −0.0026 (9) | −0.0065 (11) | −0.0027 (10) |
C23 | 0.0376 (11) | 0.0591 (14) | 0.0644 (14) | 0.0013 (10) | −0.0110 (10) | −0.0036 (11) |
C24 | 0.0412 (11) | 0.0518 (13) | 0.0490 (12) | 0.0119 (10) | −0.0002 (9) | 0.0047 (10) |
C25 | 0.0525 (12) | 0.0380 (12) | 0.0536 (13) | 0.0057 (9) | 0.0003 (10) | 0.0015 (9) |
C26 | 0.0424 (11) | 0.0398 (12) | 0.0475 (12) | 0.0005 (9) | −0.0041 (9) | 0.0000 (9) |
O12—N1 | 1.221 (2) | C13—H13 | 0.93 |
O11—N1 | 1.215 (2) | C14—C15 | 1.375 (3) |
O22—N2 | 1.216 (3) | C15—C16 | 1.366 (3) |
O21—N2 | 1.217 (2) | C15—H15 | 0.93 |
N11—N12 | 1.340 (2) | C16—H16 | 0.93 |
N11—C11 | 1.383 (2) | C21—C26 | 1.383 (2) |
N11—H11 | 0.86 | C21—C22 | 1.398 (3) |
N12—N13 | 1.263 (2) | C22—C23 | 1.372 (3) |
N13—C21 | 1.430 (2) | C22—H22 | 0.93 |
N1—C14 | 1.453 (2) | C23—C24 | 1.375 (3) |
N2—C24 | 1.470 (3) | C23—H23 | 0.93 |
C11—C12 | 1.392 (2) | C24—C25 | 1.373 (3) |
C11—C16 | 1.401 (3) | C25—C26 | 1.381 (3) |
C12—C13 | 1.365 (3) | C25—H25 | 0.93 |
C12—H12 | 0.93 | C26—H26 | 0.93 |
C13—C14 | 1.386 (3) | ||
N2—O21—O21i | 79.90 (13) | C15—C14—C13 | 121.56 (18) |
N2—O21—C16ii | 153.54 (16) | C15—C14—N1 | 119.05 (18) |
O21i—O21—C16ii | 109.49 (9) | C13—C14—N1 | 119.39 (17) |
N12—N11—C11 | 120.09 (16) | C16—C15—C14 | 119.80 (19) |
N12—N11—O12iii | 135.19 (12) | C16—C15—H15 | 120.1 |
C11—N11—O12iii | 104.71 (11) | C14—C15—H15 | 120.1 |
N12—N11—C21iv | 89.44 (11) | C15—C16—C11 | 119.46 (18) |
C11—N11—C21iv | 77.44 (11) | C15—C16—O21v | 87.76 (13) |
O12iii—N11—C21iv | 101.72 (7) | C11—C16—O21v | 148.78 (13) |
N12—N11—H11 | 120.0 | C15—C16—H16 | 120.3 |
C11—N11—H11 | 120.0 | C11—C16—H16 | 120.3 |
C21iv—N11—H11 | 103.1 | C26—C21—C22 | 119.97 (19) |
N13—N12—N11 | 112.32 (15) | C26—C21—N13 | 115.84 (18) |
N12—N13—C21 | 112.14 (15) | C22—C21—N13 | 124.18 (18) |
O11—N1—O12 | 121.69 (18) | C23—C22—C21 | 119.5 (2) |
O11—N1—C14 | 118.83 (18) | C23—C22—H22 | 120.2 |
O12—N1—C14 | 119.48 (17) | C21—C22—H22 | 120.2 |
O22—N2—O21 | 123.5 (2) | C22—C23—C24 | 119.21 (19) |
O22—N2—C24 | 118.3 (2) | C22—C23—H23 | 120.4 |
O21—N2—C24 | 118.2 (2) | C24—C23—H23 | 120.4 |
N11—C11—C12 | 119.18 (17) | C25—C24—C23 | 122.50 (18) |
N11—C11—C16 | 120.93 (16) | C25—C24—N2 | 118.6 (2) |
C12—C11—C16 | 119.88 (17) | C23—C24—N2 | 118.9 (2) |
C13—C12—C11 | 120.33 (18) | C24—C25—C26 | 118.24 (19) |
C13—C12—H12 | 119.8 | C24—C25—H25 | 120.9 |
C11—C12—H12 | 119.8 | C26—C25—H25 | 120.9 |
C12—C13—C14 | 118.96 (18) | C25—C26—C21 | 120.52 (19) |
C12—C13—H13 | 120.5 | C25—C26—H26 | 119.7 |
C14—C13—H13 | 120.5 | C21—C26—H26 | 119.7 |
Symmetry codes: (i) −x, −y+2, −z; (ii) −x, y+1/2, −z+1/2; (iii) −x+1, y+1/2, −z+3/2; (iv) x, −y+3/2, z+1/2; (v) −x, y−1/2, −z+1/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
N11—H11···O12iii | 0.86 | 2.11 | 2.929 (2) | 159 |
C12—H12···O12iii | 0.93 | 2.49 | 3.248 (3) | 139 |
C16—H16···O21v | 0.93 | 2.50 | 3.194 (3) | 131 |
C25—H25···O11vi | 0.93 | 2.46 | 3.222 (3) | 140 |
Symmetry codes: (iii) −x+1, y+1/2, −z+3/2; (v) −x, y−1/2, −z+1/2; (vi) x, y+1, z. |
Experimental details
Crystal data | |
Chemical formula | C12H9N5O4 |
Mr | 287.24 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 293 |
a, b, c (Å) | 13.452 (1), 13.671 (2), 7.034 (2) |
β (°) | 93.442 (11) |
V (Å3) | 1291.2 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.12 |
Crystal size (mm) | 0.30 × 0.20 × 0.10 |
Data collection | |
Diffractometer | Enraf–Nonius CAD-4 diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2581, 2375, 1405 |
Rint | 0.017 |
(sin θ/λ)max (Å−1) | 0.604 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.038, 0.124, 0.98 |
No. of reflections | 2375 |
No. of parameters | 191 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.18, −0.16 |
Computer programs: CAD-4 EXPRESS (Enraf Nonius, 1994), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), ORTEP-3 for Windows (Farrugia, 1997), PLATON (Spek 2003), WinGX publication routines (Farrugia, 1999).
O12—N1 | 1.221 (2) | N11—N12 | 1.340 (2) |
O11—N1 | 1.215 (2) | N11—C11 | 1.383 (2) |
O22—N2 | 1.216 (3) | N12—N13 | 1.263 (2) |
O21—N2 | 1.217 (2) | N13—C21 | 1.430 (2) |
N12—N11—C11 | 120.09 (16) | N12—N13—C21 | 112.14 (15) |
N13—N12—N11 | 112.32 (15) |
D—H···A | D—H | H···A | D···A | D—H···A |
N11—H11···O12i | 0.86 | 2.11 | 2.929 (2) | 159 |
C12—H12···O12i | 0.93 | 2.49 | 3.248 (3) | 139 |
C16—H16···O21ii | 0.93 | 2.50 | 3.194 (3) | 131 |
C25—H25···O11iii | 0.93 | 2.46 | 3.222 (3) | 140 |
Symmetry codes: (i) −x+1, y+1/2, −z+3/2; (ii) −x, y−1/2, −z+1/2; (iii) x, y+1, z. |
Numerous examples of free 1,3-disubstituted triazenes, RN═N—N(H)R, characterized by X-ray diffraction studies confirm a trans stereochemistry about the N═N double bond (Moore & Robinson, 1986). During the past few decades, asymmetric alkyl/aryl-substituted triazenes have been investigated for their biological activity. The resonance effect in the diazoamino group has been related to the antitumour activity of some triazene derivatives (Zhang et al., 1999). On the other hand, studies of molecules with DNA binding affinity indicate that the planarity has a marked effect on the insertion between the base pairs (Mahadevan & Palaniandavar, 1998; Zhen et al., 1999, 2000). We report here the synthesis and the structural characterization of the title compound, (I), a symmetric disubstituted 1,3-diaryltriazene that has π acid nitro groups on the p-substituted terminal aryl (ar) rings.
The molecular structure of (I) is shown in Fig. 1 and selected geometric parameters are given in Table 1. Deviations from typical N—N and Car—N bond lengths suggest that the delocalization of the π electrons on the triazene group has extended to the terminal 4-nitrophenyl substituents. The N12δb N13 bond [1.263 (2) Å] is longer than the characteristic double bond (1.24 Å), whereas the N11—N12 bond [1.340 (2) Å] is shorter than the characteristic value for a single bond (1.44 Å) (International Tables for X-Ray Crystallography, 1985, Vol. III, p. 270). Both the N11—C11 [1.383 (2) Å] and the N13—C21 [1.430 (2) Å] bond is shorter than the length expected for a Car—N single bond. These values are in good agreement with the distances found in the related compound 1,3-bis(3-nitrophenyl)triazene [N4═N3 = 1.261 (2) Å, N2—N3 = 1.326 (2) Å, N2—C5 = 1.393 (2) Å and N4—C11 = 1.426 (2) Å; Zhang et al., 1999].
The crystal structure contains molecules related by a twofold screw axis, which form helical chains along the [010] crystallographic direction via N—H···O hydrogen bonds (Table 2). These chains are linked by C—H···O intermolecular interactions (Table 2) to generate sheets in the (10–1) plane (Fig. 2). These sheets are then linked into a three-dimensional molecular array by N···C and O···O π–π interactions [N11···C21iv = 3.388 (3) Å and O21···O21v = 3.117 (4) Å; symmetry codes: (iv) x,-y + 3/2, z + 1/2; (vi) −x, −y + 2,-z]. These values are in good agreement with the π–π contacts found in 1,3-bis(3-nitrophenyl)triazene [N···C = 3.387 (3) Å and O···O = 3.182 (3) Å; Zhang et al., 1999].
Because of the strong π acidity of the nitro groups, which favours the delocalization of the π electrons and the conjugation between the C11–C16 and C21–C26 phenyl rings and the N═N—N(H) moiety, the whole molecule is almost planar [interplanar angles O11/N1/O12|C11–C16 = 7.3 (1)°, O21/N2/O22|C21–C26 = 8.8 (3)°, C11–C16|H11/N11/N12/N13 = 6.4 (1)°, C21–C22|N13/N12/N11/H11 = 3.7 (1)°]. The weak intermolecular C16···O21ii contact [3.194 (3) Å; see Table 2 for symmetry code) causes the C11–C16 phenyl ring to deviate by an angle of 6.4 (1)° from the plane defined by the N13═N12—N11—H11 moiety, while the C21—C26 phenyl ring remains nearly coplanar with the diazoamino group.