Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807036501/hk2282sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807036501/hk2282Isup2.hkl |
CCDC reference: 657890
Key indicators
- Single-crystal X-ray study
- T = 296 K
- Mean (C-C) = 0.003 Å
- Disorder in main residue
- R factor = 0.051
- wR factor = 0.152
- Data-to-parameter ratio = 13.0
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT063_ALERT_3_C Crystal Probably too Large for Beam Size ....... 0.66 mm PLAT242_ALERT_2_C Check Low Ueq as Compared to Neighbors for N1B PLAT242_ALERT_2_C Check Low Ueq as Compared to Neighbors for N2B PLAT301_ALERT_3_C Main Residue Disorder ......................... 11.00 Perc. PLAT480_ALERT_4_C Long H...A H-Bond Reported H2 .. O1 .. 2.65 Ang.
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 5 ALERT level C = Check and explain 0 ALERT level G = General alerts; check 0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 2 ALERT type 2 Indicator that the structure model may be wrong or deficient 2 ALERT type 3 Indicator that the structure quality may be low 1 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check
For general background, see: Stenhouse (1868); Mohlau (1883); Witt (1909); Elion (1923a,b); Fuch (1923); Knecht (1924); Venkataraman (1970); Egli et al. (1991); Marmion (1991); Garg & Sharma (1996); Modest et al. (1957); Ravindranath et al. (1983); Etter (1990). For related literature, see: Odabaşoğlu et al. (2003, 2007); Ersanlı, Albayrak et al. (2004); Ersanlı, Odabaşoğlu et al. (2004); Çakır et al. (2005); Şahin et al. (2005a,b,c,d,e). For bond-length data, see: Allen et al. (1987).
The title compound was prepared according to the literature method (Odabaşoğlu et al., 2003), using aniline and 2-methylphenol as starting materials. The product was crystallized from acetic acid solution to obtain well shaped crystals (yield; 80%, m.p. 408–410 K).
When the crystal structure was solved,the atoms N1A and N2A were found to be disordered over two positions. During refinement with anisotropic thermal parameters, the occupancies of disordered N atoms were kept fixed as N1A = 0.63, N1B = 0.37, N2A = 0.63 and N2B = 0.37. H atoms were positioned geometrically with O—H = 0.82 Å (for OH) and C—H = 0.93 and 0.96 Å for aromatic and methyl H atoms, respectively, and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C,O), where x = 1.2 for aromaic H and x = 1.5 for all other H atoms.
Azo compounds were described over 150 years ago (Stenhouse, 1868; Mohlau, 1883; Witt, 1909; Elion, 1923a,b; Fuch, 1923; Knecht, 1924). They are the oldest and largest class of industrially synthesized organic dyes due to their versatile applications in various fields, such as dyeing textile fibers, biomedical studies, advanced applications in organic synthesis and high technology areas such as lasers, liquid crystalline displays, electro-optical devices and ink-jet printers (Venkataraman, 1970; Egli et al., 1991). There are about 3000 azo dyes currently in use all over the world. The great majority of them are monoazo compounds, which have the common structure unit of the azo chromophore, –N=N–, linking two aromatic systems. The textile industry is the largest consumer of dyestuffs. Although some azo dyes have been reported to be toxic, dozens of additional monoazo dyes are permitted in drugs and cosmetics (Marmion, 1991). The pharmaceutical importance of compounds including an arylazo group has been extensively reported in the literature (Garg & Sharma, 1996; Modest et al., 1957). The oxidation-reduction behaviors of these compounds play an important role in their biological activities (Ravindranath et al., 1983). The structures of some azo derivatives have been the subject of much interest in our laboratory (Odabaşoğlu et al., 2003, 2007; Ersanlı, Albayrak et al., 2004; Ersanlı, Odabaşoğlu et al., 2004; Çakır et al., 2005; Şahin et al., 2005a,b,c,d,e). In view of the importance of the title compound, (I), we report herein its crystal structure.
In the molecule of the title compound, (I), (Fig. 1) the bond lengths and angles are generally within normal ranges (Allen et al., 1987). In the azo group, the N—C and N—N bonds and C—N—N angles are slightly deviate from their normal values (Table 1), due to the disordered N1A and N2A atoms. Aromatic rings adopt a trans configuration about the azo functional group, as observed in the structures of other previously reported azo compounds. Except the methyl protons, all atoms are in the same plane and the dihedral angle between the two aromatic rings is 1.38 (7)°.
In the crystal structure, intermolecular O—H···N and C—H···O hydrogen bonds (Table 2) link the molecules (Fig. 2) to form two edge fused R22(6) motifs (Etter, 1990). They are also connected by C—H···π and π···π interactions between (C1–C6) rings at (x, y, z) and (-x, 1 - y, 1 - z), where the centroid-centroid distance and plane-plane separation are 3.708 (1) Å and 3.418 Å, respectively, (Fig. 3) to form a three-dimensional network.
For general background, see: Stenhouse (1868); Mohlau (1883); Witt (1909); Elion (1923a,b); Fuch (1923); Knecht (1924); Venkataraman (1970); Egli et al. (1991); Marmion (1991); Garg & Sharma (1996); Modest et al. (1957); Ravindranath et al. (1983); Etter (1990). For related literature, see: Odabaşoğlu et al. (2003, 2007); Ersanlı, Albayrak et al. (2004); Ersanlı, Odabaşoğlu et al. (2004); Çakır et al. (2005); Şahin et al. (2005a,b,c,d,e). For bond-length data, see: Allen et al. (1987).
Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2002); 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); software used to prepare material for publication: WinGX (Farrugia, 1999).
C13H12N2O | F(000) = 448 |
Mr = 212.25 | Dx = 1.295 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 15802 reflections |
a = 9.0537 (6) Å | θ = 1.9–28.0° |
b = 10.5716 (9) Å | µ = 0.08 mm−1 |
c = 12.0287 (7) Å | T = 296 K |
β = 108.952 (4)° | Plate, brown |
V = 1088.88 (13) Å3 | 0.66 × 0.48 × 0.14 mm |
Z = 4 |
Stoe IPDS2 diffractometer | 2131 independent reflections |
Radiation source: sealed X-ray tube, 12 x 0.4 mm long-fine focus | 1457 reflections with I > 2σ(I) |
Plane graphite monochromator | Rint = 0.049 |
Detector resolution: 6.67 pixels mm-1 | θmax = 26.0°, θmin = 2.4° |
ω scans | h = −11→11 |
Absorption correction: integration (X-RED32; Stoe & Cie, 2002) | k = −13→13 |
Tmin = 0.747, Tmax = 0.949 | l = −14→14 |
15802 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)] = 0.051 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.152 | H-atom parameters constrained |
S = 1.05 | w = 1/[σ2(Fo2) + (0.0899P)2 + 0.0268P] where P = (Fo2 + 2Fc2)/3 |
2131 reflections | (Δ/σ)max < 0.001 |
164 parameters | Δρmax = 0.17 e Å−3 |
0 restraints | Δρmin = −0.16 e Å−3 |
C13H12N2O | V = 1088.88 (13) Å3 |
Mr = 212.25 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 9.0537 (6) Å | µ = 0.08 mm−1 |
b = 10.5716 (9) Å | T = 296 K |
c = 12.0287 (7) Å | 0.66 × 0.48 × 0.14 mm |
β = 108.952 (4)° |
Stoe IPDS2 diffractometer | 2131 independent reflections |
Absorption correction: integration (X-RED32; Stoe & Cie, 2002) | 1457 reflections with I > 2σ(I) |
Tmin = 0.747, Tmax = 0.949 | Rint = 0.049 |
15802 measured reflections |
R[F2 > 2σ(F2)] = 0.051 | 0 restraints |
wR(F2) = 0.152 | H-atom parameters constrained |
S = 1.05 | Δρmax = 0.17 e Å−3 |
2131 reflections | Δρmin = −0.16 e Å−3 |
164 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. |
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 | Occ. (<1) | |
O1 | 0.73324 (15) | −0.02601 (11) | 0.37389 (11) | 0.0732 (4) | |
H1 | 0.7186 | −0.0445 | 0.3049 | 0.110* | |
N1A | 0.2873 (5) | 0.4216 (4) | 0.3666 (5) | 0.0676 (10) | 0.63 |
N2A | 0.3664 (4) | 0.3614 (3) | 0.4494 (4) | 0.0696 (7) | 0.63 |
N1B | 0.3083 (6) | 0.4176 (4) | 0.4572 (5) | 0.0504 (11) | 0.37 |
N2B | 0.3275 (8) | 0.3706 (5) | 0.3604 (7) | 0.0501 (14) | 0.37 |
C1 | 0.2013 (2) | 0.51896 (18) | 0.4215 (3) | 0.0841 (7) | |
C2 | 0.0993 (2) | 0.5789 (2) | 0.3269 (2) | 0.0864 (6) | |
H2 | 0.0932 | 0.5553 | 0.2511 | 0.104* | |
C3 | 0.0051 (2) | 0.6746 (2) | 0.3441 (2) | 0.0867 (6) | |
H3 | −0.0647 | 0.7148 | 0.2795 | 0.104* | |
C4 | 0.0135 (2) | 0.71075 (19) | 0.4552 (2) | 0.0808 (6) | |
H4 | −0.0501 | 0.7754 | 0.4661 | 0.097* | |
C5 | 0.1155 (3) | 0.6516 (2) | 0.5498 (2) | 0.0852 (6) | |
H5 | 0.1215 | 0.6762 | 0.6253 | 0.102* | |
C6 | 0.2091 (2) | 0.5562 (2) | 0.5342 (3) | 0.0896 (7) | |
H6 | 0.2783 | 0.5162 | 0.5992 | 0.108* | |
C7 | 0.4448 (3) | 0.26581 (18) | 0.3974 (3) | 0.0822 (7) | |
C8 | 0.5429 (3) | 0.20592 (19) | 0.4970 (2) | 0.0795 (6) | |
H8 | 0.5426 | 0.2330 | 0.5705 | 0.095* | |
C9 | 0.6396 (2) | 0.10893 (17) | 0.49118 (15) | 0.0657 (5) | |
C10 | 0.63655 (19) | 0.06967 (14) | 0.37949 (14) | 0.0555 (4) | |
C11 | 0.5386 (2) | 0.12666 (16) | 0.27975 (16) | 0.0631 (5) | |
H11 | 0.5372 | 0.0986 | 0.2061 | 0.076* | |
C12 | 0.4438 (2) | 0.22363 (17) | 0.2880 (2) | 0.0733 (5) | |
H12 | 0.3782 | 0.2616 | 0.2202 | 0.088* | |
C13 | 0.7481 (3) | 0.0461 (2) | 0.59793 (18) | 0.0968 (8) | |
H13A | 0.8540 | 0.0581 | 0.5997 | 0.145* | |
H13B | 0.7253 | −0.0427 | 0.5955 | 0.145* | |
H13C | 0.7347 | 0.0826 | 0.6671 | 0.145* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0869 (9) | 0.0648 (7) | 0.0624 (8) | 0.0110 (7) | 0.0166 (6) | 0.0011 (6) |
N1A | 0.065 (2) | 0.073 (3) | 0.063 (3) | −0.0147 (17) | 0.0179 (17) | 0.005 (2) |
N2A | 0.0717 (18) | 0.074 (2) | 0.062 (2) | −0.0149 (15) | 0.0205 (17) | 0.0044 (16) |
N1B | 0.055 (2) | 0.048 (2) | 0.055 (4) | 0.0076 (17) | 0.027 (2) | −0.002 (2) |
N2B | 0.060 (3) | 0.045 (3) | 0.048 (4) | −0.003 (2) | 0.021 (2) | 0.000 (2) |
C1 | 0.0572 (10) | 0.0567 (10) | 0.141 (2) | −0.0070 (8) | 0.0366 (13) | −0.0023 (12) |
C2 | 0.0700 (12) | 0.0943 (15) | 0.0991 (17) | −0.0051 (11) | 0.0331 (12) | −0.0146 (12) |
C3 | 0.0675 (12) | 0.0923 (15) | 0.0983 (18) | 0.0053 (11) | 0.0242 (11) | 0.0170 (12) |
C4 | 0.0765 (13) | 0.0680 (11) | 0.1081 (19) | 0.0003 (10) | 0.0439 (13) | −0.0014 (11) |
C5 | 0.0815 (13) | 0.0839 (13) | 0.0917 (16) | −0.0144 (12) | 0.0300 (12) | 0.0015 (12) |
C6 | 0.0654 (12) | 0.0755 (13) | 0.118 (2) | −0.0094 (10) | 0.0169 (12) | 0.0234 (13) |
C7 | 0.0767 (13) | 0.0543 (10) | 0.136 (2) | −0.0137 (9) | 0.0627 (14) | −0.0183 (12) |
C8 | 0.1009 (15) | 0.0697 (11) | 0.0870 (15) | −0.0335 (11) | 0.0571 (13) | −0.0286 (11) |
C9 | 0.0841 (12) | 0.0621 (10) | 0.0527 (10) | −0.0265 (9) | 0.0247 (9) | −0.0069 (8) |
C10 | 0.0651 (9) | 0.0490 (8) | 0.0531 (10) | −0.0050 (7) | 0.0201 (8) | −0.0013 (7) |
C11 | 0.0733 (11) | 0.0631 (10) | 0.0540 (10) | −0.0020 (8) | 0.0220 (8) | 0.0033 (7) |
C12 | 0.0668 (11) | 0.0610 (10) | 0.0928 (15) | 0.0018 (8) | 0.0268 (10) | 0.0148 (9) |
C13 | 0.1265 (19) | 0.1026 (16) | 0.0507 (12) | −0.0450 (15) | 0.0141 (12) | 0.0009 (11) |
C1—C2 | 1.367 (3) | C7—N2B | 1.501 (7) |
C1—C6 | 1.390 (4) | C8—C9 | 1.365 (3) |
C1—N1B | 1.418 (6) | C8—H8 | 0.9300 |
C1—N1A | 1.558 (6) | C9—C10 | 1.398 (2) |
C2—C3 | 1.381 (3) | C9—C13 | 1.495 (3) |
C2—H2 | 0.9300 | C10—O1 | 1.3537 (19) |
C3—C4 | 1.368 (3) | C10—C11 | 1.377 (2) |
C3—H3 | 0.9300 | C11—C12 | 1.362 (3) |
C4—C5 | 1.362 (3) | C11—H11 | 0.9300 |
C4—H4 | 0.9300 | C12—H12 | 0.9300 |
C5—C6 | 1.369 (3) | C13—H13A | 0.9600 |
C5—H5 | 0.9300 | C13—H13B | 0.9600 |
C6—H6 | 0.9300 | C13—H13C | 0.9600 |
C7—C12 | 1.386 (3) | N1A—N2A | 1.208 (6) |
C7—C8 | 1.390 (3) | N1B—N2B | 1.324 (9) |
C7—N2A | 1.485 (5) | O1—H1 | 0.8200 |
C2—C1—C6 | 119.1 (2) | C9—C8—H8 | 118.7 |
C2—C1—N1B | 144.5 (3) | C7—C8—H8 | 118.7 |
C6—C1—N1B | 96.1 (3) | C8—C9—C10 | 117.35 (18) |
C2—C1—N1A | 104.3 (3) | C8—C9—C13 | 122.9 (2) |
C6—C1—N1A | 136.5 (3) | C10—C9—C13 | 119.70 (19) |
C1—C2—C3 | 119.9 (2) | O1—C10—C11 | 121.83 (16) |
C1—C2—H2 | 120.1 | O1—C10—C9 | 117.30 (16) |
C3—C2—H2 | 120.1 | C11—C10—C9 | 120.87 (17) |
C4—C3—C2 | 120.7 (2) | C12—C11—C10 | 120.56 (18) |
C4—C3—H3 | 119.7 | C12—C11—H11 | 119.7 |
C2—C3—H3 | 119.7 | C10—C11—H11 | 119.7 |
C5—C4—C3 | 119.7 (2) | C11—C12—C7 | 120.1 (2) |
C5—C4—H4 | 120.2 | C11—C12—H12 | 119.9 |
C3—C4—H4 | 120.2 | C7—C12—H12 | 119.9 |
C4—C5—C6 | 120.4 (2) | C9—C13—H13A | 109.5 |
C4—C5—H5 | 119.8 | C9—C13—H13B | 109.5 |
C6—C5—H5 | 119.8 | H13A—C13—H13B | 109.5 |
C5—C6—C1 | 120.3 (2) | C9—C13—H13C | 109.5 |
C5—C6—H6 | 119.9 | H13A—C13—H13C | 109.5 |
C1—C6—H6 | 119.9 | H13B—C13—H13C | 109.5 |
C12—C7—C8 | 118.45 (18) | N2A—N1A—C1 | 104.3 (6) |
C12—C7—N2A | 139.7 (3) | N1A—N2A—C7 | 104.6 (6) |
C8—C7—N2A | 101.8 (2) | N2B—N1B—C1 | 106.6 (7) |
C12—C7—N2B | 99.9 (3) | N1B—N2B—C7 | 107.2 (7) |
C8—C7—N2B | 141.7 (3) | C10—O1—H1 | 109.5 |
C9—C8—C7 | 122.63 (19) | ||
C6—C1—C2—C3 | −0.4 (3) | C9—C10—C11—C12 | 0.7 (3) |
N1B—C1—C2—C3 | 173.1 (3) | C10—C11—C12—C7 | −0.1 (3) |
N1A—C1—C2—C3 | −178.5 (2) | C8—C7—C12—C11 | −0.7 (3) |
C1—C2—C3—C4 | 0.4 (3) | N2A—C7—C12—C11 | −179.1 (2) |
C2—C3—C4—C5 | −0.1 (3) | N2B—C7—C12—C11 | 179.1 (3) |
C3—C4—C5—C6 | −0.1 (3) | C2—C1—N1A—N2A | −173.9 (3) |
C4—C5—C6—C1 | 0.1 (3) | C6—C1—N1A—N2A | 8.5 (4) |
C2—C1—C6—C5 | 0.1 (3) | N1B—C1—N1A—N2A | −1.3 (3) |
N1B—C1—C6—C5 | −176.1 (2) | C1—N1A—N2A—C7 | 178.2 (2) |
N1A—C1—C6—C5 | 177.5 (3) | C12—C7—N2A—N1A | −5.9 (4) |
C12—C7—C8—C9 | 1.0 (3) | C8—C7—N2A—N1A | 175.6 (2) |
N2A—C7—C8—C9 | 179.94 (18) | N2B—C7—N2A—N1A | −3.0 (5) |
N2B—C7—C8—C9 | −178.6 (4) | C2—C1—N1B—N2B | 9.6 (6) |
C7—C8—C9—C10 | −0.5 (3) | C6—C1—N1B—N2B | −176.1 (3) |
C7—C8—C9—C13 | 178.53 (17) | N1A—C1—N1B—N2B | −2.9 (4) |
C8—C9—C10—O1 | 179.59 (14) | C1—N1B—N2B—C7 | 178.2 (3) |
C13—C9—C10—O1 | 0.6 (2) | C12—C7—N2B—N1B | 176.7 (4) |
C8—C9—C10—C11 | −0.4 (2) | C8—C7—N2B—N1B | −3.6 (7) |
C13—C9—C10—C11 | −179.46 (16) | N2A—C7—N2B—N1B | −1.4 (3) |
O1—C10—C11—C12 | −179.29 (15) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N2Bi | 0.82 | 2.10 | 2.904 (8) | 168 |
O1—H1···N1Ai | 0.82 | 2.08 | 2.891 (6) | 172 |
C2—H2···O1ii | 0.93 | 2.65 | 3.427 (3) | 142 |
C12—H12···O1ii | 0.93 | 2.57 | 3.367 (2) | 144 |
Symmetry codes: (i) −x+1, y−1/2, −z+1/2; (ii) −x+1, y+1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C13H12N2O |
Mr | 212.25 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 296 |
a, b, c (Å) | 9.0537 (6), 10.5716 (9), 12.0287 (7) |
β (°) | 108.952 (4) |
V (Å3) | 1088.88 (13) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.66 × 0.48 × 0.14 |
Data collection | |
Diffractometer | Stoe IPDS2 |
Absorption correction | Integration (X-RED32; Stoe & Cie, 2002) |
Tmin, Tmax | 0.747, 0.949 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 15802, 2131, 1457 |
Rint | 0.049 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.051, 0.152, 1.05 |
No. of reflections | 2131 |
No. of parameters | 164 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.17, −0.16 |
Computer programs: X-AREA (Stoe & Cie, 2002), X-AREA, X-RED32 (Stoe & Cie, 2002), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N2Bi | 0.82 | 2.10 | 2.904 (8) | 168.1 |
O1—H1···N1Ai | 0.82 | 2.08 | 2.891 (6) | 171.6 |
C2—H2···O1ii | 0.93 | 2.65 | 3.427 (3) | 142.0 |
C12—H12···O1ii | 0.93 | 2.57 | 3.367 (2) | 144.2 |
Symmetry codes: (i) −x+1, y−1/2, −z+1/2; (ii) −x+1, y+1/2, −z+1/2. |
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Azo compounds were described over 150 years ago (Stenhouse, 1868; Mohlau, 1883; Witt, 1909; Elion, 1923a,b; Fuch, 1923; Knecht, 1924). They are the oldest and largest class of industrially synthesized organic dyes due to their versatile applications in various fields, such as dyeing textile fibers, biomedical studies, advanced applications in organic synthesis and high technology areas such as lasers, liquid crystalline displays, electro-optical devices and ink-jet printers (Venkataraman, 1970; Egli et al., 1991). There are about 3000 azo dyes currently in use all over the world. The great majority of them are monoazo compounds, which have the common structure unit of the azo chromophore, –N=N–, linking two aromatic systems. The textile industry is the largest consumer of dyestuffs. Although some azo dyes have been reported to be toxic, dozens of additional monoazo dyes are permitted in drugs and cosmetics (Marmion, 1991). The pharmaceutical importance of compounds including an arylazo group has been extensively reported in the literature (Garg & Sharma, 1996; Modest et al., 1957). The oxidation-reduction behaviors of these compounds play an important role in their biological activities (Ravindranath et al., 1983). The structures of some azo derivatives have been the subject of much interest in our laboratory (Odabaşoğlu et al., 2003, 2007; Ersanlı, Albayrak et al., 2004; Ersanlı, Odabaşoğlu et al., 2004; Çakır et al., 2005; Şahin et al., 2005a,b,c,d,e). In view of the importance of the title compound, (I), we report herein its crystal structure.
In the molecule of the title compound, (I), (Fig. 1) the bond lengths and angles are generally within normal ranges (Allen et al., 1987). In the azo group, the N—C and N—N bonds and C—N—N angles are slightly deviate from their normal values (Table 1), due to the disordered N1A and N2A atoms. Aromatic rings adopt a trans configuration about the azo functional group, as observed in the structures of other previously reported azo compounds. Except the methyl protons, all atoms are in the same plane and the dihedral angle between the two aromatic rings is 1.38 (7)°.
In the crystal structure, intermolecular O—H···N and C—H···O hydrogen bonds (Table 2) link the molecules (Fig. 2) to form two edge fused R22(6) motifs (Etter, 1990). They are also connected by C—H···π and π···π interactions between (C1–C6) rings at (x, y, z) and (-x, 1 - y, 1 - z), where the centroid-centroid distance and plane-plane separation are 3.708 (1) Å and 3.418 Å, respectively, (Fig. 3) to form a three-dimensional network.