organic compounds
2-[(4-Ethoxyphenyl)iminomethyl]-5-methoxyphenol
aDepartment of Physics, Faculty of Arts and Sciences, Ondokuz Mayıs University, Kurupelit, TR-55139 Samsun, Turkey, bSinop University, Gerze Sinop Vocational School, Sinop, Turkey, and cDepartment of Chemistry, Faculty of Arts and Sciences, Ondokuz Mayıs University, 55139 Samsun, Turkey
*Correspondence e-mail: sgul@omu.edu.tr
The title compound, C16H17NO3, a Schiff base, is stabilized in the solid state in the phenol–imine tautomeric form, with the H atom located on the hydroxy O atom rather than on the N atom. This H atom is involved in a strong intramolecular O—H⋯N hydrogen bond. The molecule is almost planar, the angle between the benzene rings being 4.43 (13)°. C—H⋯π interactions are also present.
Related literature
For the industrial and biological properties of et al. (1999); Taggi et al. (2002). For Schiff base see: Şahin et al. (2005); Hadjoudis et al. (1987).
see: KariaExperimental
Crystal data
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Refinement
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Data collection: X-AREA (Stoe & Cie, 2002); cell X-AREA; data reduction: X-RED32 (Stoe & Cie, 2002); 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, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).
Supporting information
https://doi.org/10.1107/S1600536809040240/bh2250sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536809040240/bh2250Isup2.hkl
The title compound was prepared by refluxing a mixture of a solution containing 2-hydroxy-4-methoxy-benzaldehyde (0.0237 g, 0.156 mmol) in 20 ml ethanol and a solution containing 4-ethoxyaniline (0.0214 g, 0.156 mmol) in 20 ml ethanol. The reaction mixture was stirred for 1 h under reflux. Crystals suitable for X-ray analysis were obtained from ethylalcohol by slow evaporation (yield % 71; m.p. 381–383 K).
Phenolic H atom (H1) was first detected in a difference map, but eventually fixed in calculated position, with the O—H bond length constrained to 0.82 Å and Uiso(H1) = 1.5Ueq(O1). Other H atoms were also placed in calculated positions and constrained to ride on their parents atoms, with C—H = 0.93–0.96 Å, and Uiso(H) = 1.2Ueq(C) or 1.5Ueq(C). For atom C12, anisotropic displacement parameters were restrained to approximate an isotropic behaviour.
Schiff bases are used as substrates in the preparation of a number of industrial and biologically active compounds via ring closure,
and replacement reactions (Karia et al., 1999). Moreover, are also known to have biological activities such as antimicrobial, antifungal, antitumor and as herbicides. On the industrial scale, they have a wide range of applications such as dyes and pigments (Taggi et al., 2002). In general, display two possible tautomeric forms, the phenol-imine (Hadjoudis et al., 1987) and keto-amine (Şahin et al., 2005) forms. Depending on the tautomers two types of intramolecular hydrogen bonds are observed in O—H···N in phenol-imine and N—H···O in keto-amine tautomers. Our X-ray investigation of the title compound indicates that the phenol-imine tautomer is favoured over the keto-amine tautomer (Fig. 1).Selected bond lengths of the title compound are given in Table 1. The N1—C8 bond length of 1.285 (3) Å is typical of a double bond. The dihedral angle between the C2···C7 and C9···C14 benzene rings is 4.43 (13)° and the compound is thus almost planar. The C5—C8—N1—C9 torsion angle is 179.3 (2)°. The compound shows a strong intramolecular hydrogen bond (O1—H1···N1) which forms a S(6) motif. The compound also contains five intermolecular C—H···π interactions. The combination of three C—H···π interactions generates chain of edge-fused R21(7)R22(15) rings running parallel to the [010] direction (Fig. 2). The details of C—H···π interactions are given in Table 2.
For the industrial and biological properties of
see: Karia et al. (1999); Taggi et al. (2002). For Schiff base see: Şahin et al. (2005); Hadjoudis et al. (1987).Data collection: X-AREA (Stoe & Cie, 2002); cell
X-AREA (Stoe & Cie, 2002); data reduction: X-RED32 (Stoe & Cie, 2002); 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, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).Fig. 1. The molecular structure of the title compound, showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. | |
Fig. 2. Part of the crystal structure of the title compound, showing the formation of a chain along [010] generated by the C—H···π interactions. |
C16H17NO3 | F(000) = 576 |
Mr = 271.31 | Dx = 1.268 Mg m−3 |
Monoclinic, P21/c | Melting point: 381 K |
Hall symbol: -P 2ybc | Mo Kα radiation, λ = 0.71073 Å |
a = 7.4609 (7) Å | Cell parameters from 5881 reflections |
b = 8.3777 (5) Å | θ = 1.8–27.3° |
c = 23.016 (2) Å | µ = 0.09 mm−1 |
β = 98.896 (8)° | T = 296 K |
V = 1421.3 (2) Å3 | Plate, yellow |
Z = 4 | 0.49 × 0.28 × 0.07 mm |
Stoe IPDS-II diffractometer | 2788 independent reflections |
Radiation source: fine-focus sealed tube | 971 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.068 |
Detector resolution: 6.67 pixels mm-1 | θmax = 26.0°, θmin = 1.8° |
ω scans | h = −8→9 |
Absorption correction: integration (X-RED32; Stoe & Cie, 2002) | k = −8→10 |
Tmin = 0.983, Tmax = 0.994 | l = −28→28 |
8971 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)] = 0.042 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.075 | H-atom parameters constrained |
S = 0.80 | w = 1/[σ2(Fo2) + (0.0187P)2] where P = (Fo2 + 2Fc2)/3 |
2788 reflections | (Δ/σ)max < 0.001 |
181 parameters | Δρmax = 0.06 e Å−3 |
6 restraints | Δρmin = −0.09 e Å−3 |
0 constraints |
C16H17NO3 | V = 1421.3 (2) Å3 |
Mr = 271.31 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 7.4609 (7) Å | µ = 0.09 mm−1 |
b = 8.3777 (5) Å | T = 296 K |
c = 23.016 (2) Å | 0.49 × 0.28 × 0.07 mm |
β = 98.896 (8)° |
Stoe IPDS-II diffractometer | 2788 independent reflections |
Absorption correction: integration (X-RED32; Stoe & Cie, 2002) | 971 reflections with I > 2σ(I) |
Tmin = 0.983, Tmax = 0.994 | Rint = 0.068 |
8971 measured reflections |
R[F2 > 2σ(F2)] = 0.042 | 6 restraints |
wR(F2) = 0.075 | H-atom parameters constrained |
S = 0.80 | Δρmax = 0.06 e Å−3 |
2788 reflections | Δρmin = −0.09 e Å−3 |
181 parameters |
x | y | z | Uiso*/Ueq | ||
C1 | −0.6165 (4) | 0.5043 (3) | 0.57051 (10) | 0.1085 (9) | |
H1A | −0.5696 | 0.6108 | 0.5697 | 0.163* | |
H1B | −0.6483 | 0.4828 | 0.6086 | 0.163* | |
H1C | −0.7222 | 0.4938 | 0.5411 | 0.163* | |
C2 | −0.3202 (4) | 0.3896 (3) | 0.59654 (12) | 0.0808 (7) | |
C3 | −0.2831 (4) | 0.4771 (3) | 0.64744 (12) | 0.0856 (8) | |
H3 | −0.3693 | 0.5465 | 0.6584 | 0.103* | |
C4 | −0.1155 (5) | 0.4605 (3) | 0.68216 (11) | 0.0800 (7) | |
C5 | 0.0154 (4) | 0.3552 (3) | 0.66750 (11) | 0.0757 (7) | |
C6 | −0.0289 (4) | 0.2690 (3) | 0.61528 (12) | 0.0893 (8) | |
H6 | 0.0557 | 0.1980 | 0.6044 | 0.107* | |
C7 | −0.1921 (4) | 0.2855 (3) | 0.57975 (11) | 0.0870 (8) | |
H7 | −0.2173 | 0.2281 | 0.5449 | 0.104* | |
C8 | 0.1875 (4) | 0.3370 (3) | 0.70488 (12) | 0.0838 (8) | |
H8 | 0.2693 | 0.2612 | 0.6953 | 0.101* | |
C9 | 0.3994 (5) | 0.4049 (3) | 0.78873 (12) | 0.0795 (7) | |
C10 | 0.4158 (4) | 0.4914 (3) | 0.84077 (13) | 0.0890 (8) | |
H10 | 0.3202 | 0.5556 | 0.8483 | 0.107* | |
C11 | 0.5712 (5) | 0.4833 (3) | 0.88123 (12) | 0.0910 (8) | |
H11 | 0.5793 | 0.5423 | 0.9158 | 0.109* | |
C12 | 0.7163 (4) | 0.3890 (3) | 0.87168 (12) | 0.0808 (7) | |
C13 | 0.7025 (4) | 0.3066 (3) | 0.81961 (12) | 0.0921 (8) | |
H13 | 0.7997 | 0.2452 | 0.8117 | 0.111* | |
C14 | 0.5468 (5) | 0.3141 (3) | 0.77915 (12) | 0.0936 (8) | |
H14 | 0.5403 | 0.2564 | 0.7444 | 0.112* | |
O3 | 0.8627 (3) | 0.38748 (19) | 0.91485 (8) | 0.0937 (5) | |
C16 | 1.0174 (4) | 0.2954 (3) | 0.90641 (11) | 0.0995 (8) | |
H16A | 1.0645 | 0.3324 | 0.8718 | 0.119* | |
H16B | 0.9841 | 0.1839 | 0.9008 | 0.119* | |
C17 | 1.1580 (4) | 0.3138 (3) | 0.95957 (11) | 0.1148 (10) | |
H17A | 1.2637 | 0.2532 | 0.9546 | 0.172* | |
H17B | 1.1108 | 0.2758 | 0.9935 | 0.172* | |
H17C | 1.1900 | 0.4245 | 0.9649 | 0.172* | |
N1 | 0.2308 (3) | 0.4230 (2) | 0.75114 (10) | 0.0830 (6) | |
O1 | −0.0840 (2) | 0.55210 (18) | 0.73075 (7) | 0.1034 (6) | |
H1 | 0.0175 | 0.5328 | 0.7486 | 0.155* | |
O2 | −0.4817 (3) | 0.39332 (19) | 0.55872 (7) | 0.0959 (5) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.104 (2) | 0.111 (2) | 0.119 (2) | 0.008 (2) | 0.0432 (17) | −0.0031 (16) |
C2 | 0.101 (3) | 0.0615 (16) | 0.086 (2) | 0.0006 (18) | 0.0332 (17) | 0.0117 (15) |
C3 | 0.113 (3) | 0.0661 (17) | 0.0850 (18) | −0.0012 (17) | 0.0390 (17) | −0.0099 (15) |
C4 | 0.110 (2) | 0.0633 (16) | 0.0734 (18) | −0.0098 (18) | 0.0350 (17) | −0.0052 (14) |
C5 | 0.107 (3) | 0.0510 (15) | 0.0770 (18) | 0.0034 (16) | 0.0393 (17) | 0.0008 (13) |
C6 | 0.128 (3) | 0.0612 (16) | 0.0856 (19) | 0.0098 (17) | 0.0385 (17) | 0.0017 (15) |
C7 | 0.122 (3) | 0.0655 (17) | 0.0777 (18) | 0.0055 (18) | 0.0277 (18) | −0.0040 (13) |
C8 | 0.110 (3) | 0.0594 (16) | 0.0882 (18) | 0.0026 (16) | 0.0367 (17) | 0.0105 (15) |
C9 | 0.113 (3) | 0.0539 (16) | 0.0788 (19) | −0.0098 (17) | 0.0378 (18) | −0.0004 (14) |
C10 | 0.095 (2) | 0.0694 (17) | 0.109 (2) | −0.0008 (16) | 0.0387 (17) | −0.0109 (16) |
C11 | 0.106 (2) | 0.0722 (18) | 0.103 (2) | −0.0002 (19) | 0.0425 (18) | −0.0223 (15) |
C12 | 0.104 (3) | 0.0599 (16) | 0.0849 (19) | −0.0066 (17) | 0.0352 (18) | −0.0046 (14) |
C13 | 0.107 (3) | 0.0849 (19) | 0.090 (2) | 0.0093 (18) | 0.0337 (17) | −0.0042 (16) |
C14 | 0.126 (3) | 0.0754 (18) | 0.089 (2) | 0.009 (2) | 0.044 (2) | −0.0130 (15) |
O3 | 0.0995 (16) | 0.0828 (12) | 0.1030 (13) | 0.0054 (11) | 0.0288 (12) | −0.0143 (9) |
C16 | 0.106 (3) | 0.0844 (18) | 0.117 (2) | 0.0038 (18) | 0.0463 (19) | −0.0041 (15) |
C17 | 0.120 (3) | 0.118 (2) | 0.107 (2) | 0.0166 (19) | 0.0188 (19) | 0.0062 (16) |
N1 | 0.111 (2) | 0.0614 (13) | 0.0824 (16) | −0.0081 (13) | 0.0317 (14) | −0.0039 (11) |
O1 | 0.1215 (16) | 0.0934 (12) | 0.0997 (12) | 0.0025 (11) | 0.0312 (10) | −0.0327 (10) |
O2 | 0.1132 (17) | 0.0798 (12) | 0.0985 (13) | 0.0076 (12) | 0.0283 (12) | −0.0057 (9) |
C1—O2 | 1.426 (3) | C9—C10 | 1.389 (3) |
C1—H1A | 0.9600 | C9—N1 | 1.420 (3) |
C1—H1B | 0.9600 | C10—C11 | 1.372 (3) |
C1—H1C | 0.9600 | C10—H10 | 0.9300 |
C2—O2 | 1.374 (3) | C11—C12 | 1.385 (3) |
C2—C3 | 1.374 (3) | C11—H11 | 0.9300 |
C2—C7 | 1.392 (3) | C12—O3 | 1.358 (3) |
C3—C4 | 1.383 (3) | C12—C13 | 1.373 (3) |
C3—H3 | 0.9300 | C13—C14 | 1.373 (3) |
C4—O1 | 1.347 (2) | C13—H13 | 0.9300 |
C4—C5 | 1.396 (3) | C14—H14 | 0.9300 |
C5—C6 | 1.398 (3) | O3—C16 | 1.426 (3) |
C5—C8 | 1.439 (3) | C16—C17 | 1.492 (3) |
C6—C7 | 1.364 (3) | C16—H16A | 0.9700 |
C6—H6 | 0.9300 | C16—H16B | 0.9700 |
C7—H7 | 0.9300 | C17—H17A | 0.9600 |
C8—N1 | 1.285 (3) | C17—H17B | 0.9600 |
C8—H8 | 0.9300 | C17—H17C | 0.9600 |
C9—C14 | 1.383 (3) | O1—H1 | 0.8200 |
O2—C1—H1A | 109.5 | C11—C10—H10 | 119.6 |
O2—C1—H1B | 109.5 | C9—C10—H10 | 119.6 |
H1A—C1—H1B | 109.5 | C10—C11—C12 | 121.3 (3) |
O2—C1—H1C | 109.5 | C10—C11—H11 | 119.3 |
H1A—C1—H1C | 109.5 | C12—C11—H11 | 119.3 |
H1B—C1—H1C | 109.5 | O3—C12—C13 | 125.3 (3) |
O2—C2—C3 | 124.7 (3) | O3—C12—C11 | 116.7 (3) |
O2—C2—C7 | 114.3 (3) | C13—C12—C11 | 118.1 (3) |
C3—C2—C7 | 121.0 (3) | C12—C13—C14 | 120.7 (3) |
C2—C3—C4 | 118.9 (3) | C12—C13—H13 | 119.6 |
C2—C3—H3 | 120.5 | C14—C13—H13 | 119.6 |
C4—C3—H3 | 120.5 | C13—C14—C9 | 121.8 (3) |
O1—C4—C3 | 116.6 (3) | C13—C14—H14 | 119.1 |
O1—C4—C5 | 121.5 (3) | C9—C14—H14 | 119.1 |
C3—C4—C5 | 121.9 (3) | C12—O3—C16 | 118.8 (2) |
C4—C5—C6 | 116.9 (3) | O3—C16—C17 | 108.3 (2) |
C4—C5—C8 | 121.1 (3) | O3—C16—H16A | 110.0 |
C6—C5—C8 | 122.0 (3) | C17—C16—H16A | 110.0 |
C7—C6—C5 | 122.3 (3) | O3—C16—H16B | 110.0 |
C7—C6—H6 | 118.9 | C17—C16—H16B | 110.0 |
C5—C6—H6 | 118.9 | H16A—C16—H16B | 108.4 |
C6—C7—C2 | 119.0 (3) | C16—C17—H17A | 109.5 |
C6—C7—H7 | 120.5 | C16—C17—H17B | 109.5 |
C2—C7—H7 | 120.5 | H17A—C17—H17B | 109.5 |
N1—C8—C5 | 121.5 (3) | C16—C17—H17C | 109.5 |
N1—C8—H8 | 119.2 | H17A—C17—H17C | 109.5 |
C5—C8—H8 | 119.2 | H17B—C17—H17C | 109.5 |
C14—C9—C10 | 117.3 (3) | C8—N1—C9 | 122.1 (2) |
C14—C9—N1 | 127.8 (3) | C4—O1—H1 | 109.5 |
C10—C9—N1 | 114.9 (3) | C2—O2—C1 | 118.0 (2) |
C11—C10—C9 | 120.8 (3) | ||
O2—C2—C3—C4 | 179.0 (2) | C9—C10—C11—C12 | −0.1 (4) |
C7—C2—C3—C4 | 0.0 (3) | C10—C11—C12—O3 | −179.1 (2) |
C2—C3—C4—O1 | 178.26 (19) | C10—C11—C12—C13 | 1.8 (4) |
C2—C3—C4—C5 | −1.2 (3) | O3—C12—C13—C14 | 178.9 (2) |
O1—C4—C5—C6 | −178.2 (2) | C11—C12—C13—C14 | −2.0 (4) |
C3—C4—C5—C6 | 1.2 (3) | C12—C13—C14—C9 | 0.6 (4) |
O1—C4—C5—C8 | 1.9 (3) | C10—C9—C14—C13 | 1.1 (3) |
C3—C4—C5—C8 | −178.6 (2) | N1—C9—C14—C13 | −179.7 (2) |
C4—C5—C6—C7 | 0.0 (3) | C13—C12—O3—C16 | 0.7 (3) |
C8—C5—C6—C7 | 179.8 (2) | C11—C12—O3—C16 | −178.4 (2) |
C5—C6—C7—C2 | −1.2 (4) | C12—O3—C16—C17 | 179.9 (2) |
O2—C2—C7—C6 | −178.0 (2) | C5—C8—N1—C9 | 179.3 (2) |
C3—C2—C7—C6 | 1.2 (3) | C14—C9—N1—C8 | 8.9 (3) |
C4—C5—C8—N1 | −4.0 (3) | C10—C9—N1—C8 | −171.8 (2) |
C6—C5—C8—N1 | 176.2 (2) | C3—C2—O2—C1 | 4.8 (3) |
C14—C9—C10—C11 | −1.3 (3) | C7—C2—O2—C1 | −176.0 (2) |
N1—C9—C10—C11 | 179.3 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N1 | 0.82 | 1.83 | 2.563 (3) | 148 |
C1—H1A···Cg2i | 0.96 | 3.32 | 4.000 (3) | 129 |
C3—H3···Cg2i | 0.93 | 3.30 | 4.155 (3) | 155 |
C8—H8···Cg2ii | 0.93 | 3.39 | 4.269 (3) | 159 |
C10—H10···Cg1i | 0.93 | 3.00 | 3.849 (3) | 153 |
C16—H16B···Cg1ii | 0.97 | 3.04 | 3.822 (3) | 139 |
Symmetry codes: (i) −x, y+1/2, −z+3/2; (ii) −x+1, y−1/2, −z+3/2. |
Experimental details
Crystal data | |
Chemical formula | C16H17NO3 |
Mr | 271.31 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 296 |
a, b, c (Å) | 7.4609 (7), 8.3777 (5), 23.016 (2) |
β (°) | 98.896 (8) |
V (Å3) | 1421.3 (2) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.49 × 0.28 × 0.07 |
Data collection | |
Diffractometer | Stoe IPDS-II |
Absorption correction | Integration (X-RED32; Stoe & Cie, 2002) |
Tmin, Tmax | 0.983, 0.994 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 8971, 2788, 971 |
Rint | 0.068 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.042, 0.075, 0.80 |
No. of reflections | 2788 |
No. of parameters | 181 |
No. of restraints | 6 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.06, −0.09 |
Computer programs: X-AREA (Stoe & Cie, 2002), X-RED32 (Stoe & Cie, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).
C1—O2 | 1.426 (3) | C8—N1 | 1.285 (3) |
C2—O2 | 1.374 (3) | C9—N1 | 1.420 (3) |
C4—O1 | 1.347 (2) | O3—C16 | 1.426 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N1 | 0.82 | 1.83 | 2.563 (3) | 147.7 |
C1—H1A···Cg2i | 0.96 | 3.3241 | 4.000 (3) | 129 |
C3—H3···Cg2i | 0.93 | 3.2959 | 4.155 (3) | 154.6 |
C8—H8···Cg2ii | 0.93 | 3.3873 | 4.269 (3) | 159 |
C10—H10···Cg1i | 0.93 | 2.9994 | 3.849 (3) | 152.6 |
C16—H16B···Cg1ii | 0.97 | 3.0402 | 3.822 (3) | 138.6 |
Symmetry codes: (i) −x, y+1/2, −z+3/2; (ii) −x+1, y−1/2, −z+3/2. |
Acknowledgements
The authors wish to acknowledge the Faculty of Arts and Sciences, Ondokuz Mayıs University, Turkey, for the use of the Stoe IPDS-II diffractometer (purchased under grant No. F279 of the University Research Fund).
References
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Schiff bases are used as substrates in the preparation of a number of industrial and biologically active compounds via ring closure, cycloaddition and replacement reactions (Karia et al., 1999). Moreover, Schiff bases are also known to have biological activities such as antimicrobial, antifungal, antitumor and as herbicides. On the industrial scale, they have a wide range of applications such as dyes and pigments (Taggi et al., 2002). In general, Schiff bases display two possible tautomeric forms, the phenol-imine (Hadjoudis et al., 1987) and keto-amine (Şahin et al., 2005) forms. Depending on the tautomers two types of intramolecular hydrogen bonds are observed in Schiff bases: O—H···N in phenol-imine and N—H···O in keto-amine tautomers. Our X-ray investigation of the title compound indicates that the phenol-imine tautomer is favoured over the keto-amine tautomer (Fig. 1).
Selected bond lengths of the title compound are given in Table 1. The N1—C8 bond length of 1.285 (3) Å is typical of a double bond. The dihedral angle between the C2···C7 and C9···C14 benzene rings is 4.43 (13)° and the compound is thus almost planar. The C5—C8—N1—C9 torsion angle is 179.3 (2)°. The compound shows a strong intramolecular hydrogen bond (O1—H1···N1) which forms a S(6) motif. The compound also contains five intermolecular C—H···π interactions. The combination of three C—H···π interactions generates chain of edge-fused R21(7)R22(15) rings running parallel to the [010] direction (Fig. 2). The details of C—H···π interactions are given in Table 2.