organic compounds
(E)-2-[(4-Fluorophenyl)iminomethyl]-5-methoxyphenol
aFaculty of Education, Sinop University, Sinop, Turkey, bDepartment of Physics, Ondokuz Mayıs University, TR-55139 Samsun, Turkey, and cChemistry Programme, Denizli Higher Vocational School, Pamukkale University, TR-20159 Denizli, Turkey
*Correspondence e-mail: calbayrak@sinop.edu.tr
In the molecule of the title compound, C14H12FNO2, the aromatic rings are oriented at a dihedral angle of 48.17 (1)°. An intramolecular O—H⋯N hydrogen bond results in the formation of a six-membered ring. The title molecule is a phenol–imine tautomer, as evidenced by the C—O [1.351 (3) Å], C—N [1.282 (3) Å], and C—C [1.416 (3)–1.445 (3) Å] bond lengths. In the crystal, molecules are linked by intermolecular C—H⋯π interactions.
Related literature
The present work is part of a structural study of et al. (2007); Odabaşoğlu et al. (2007); Albayrak et al. (2005). For related structures, see: Özek et al. (2007, 2009).
see: ÖzekExperimental
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/S1600536810000474/bt5163sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810000474/bt5163Isup2.hkl
The compound (E)-2-(4-Fluorophenylimino)methyl-5-methoxyphenol was prepared by reflux a mixture of a solution containing 4-methoxysalicylaldehyde (0.5 g 3.3 mmol) in 20 ml e thanol and a solution containing 4-fluoroaniline (0.37 g 3.3 mmol) in 20 ml e thanol. The reaction mixture was stirred for 1 h under reflux. The crystals of (E)-2-(4-Fluorophenylimino)methyl-5-methoxyphenol suitable for X-ray analysis were obtained from ethanol by slow evaporation (yield % 82; m.p. 368–369 K).
All H atoms except the hydroxyl H atom (which was freely refined) were refined using riding model with C—H distances of 0.96 Å for the methyl group and 0.93 Å for other H atoms. The displacement parameters of these H atoms were fixed at 1.2 Ueq of their parent carbon atom or 1.5 Ueq for the methyl group. The
could not be determined, and 1150 Friedel pairs were averaged before the last refinement.The present work is part of a structural study of
(Özek et al., 2009; Özek et al., 2007) and we report here the structure of (E)-2-(4-Fluorophenylimino)methyl-5-methoxyphenol, (I).The ortho-hydroxy
that show by the intramolecular proton transfer from an oxygen atom to the neighboring nitrogen atom are important compounds. These compounds can exist in three different structures as enol, keto or zwitterionic forms in the solid state. The title compound (I) consists of two aromatic rings (C1 to C6 and C9 to C14), and an imino frame (C9—N1—C8—C1). In (E)-2-(4-Fluorophenylimino)methyl- 5-methoxyphenol which adopts an E configuration about the C=N double bond, dihedral angle between the aromatic rings is 48.17 (1) °. The H atom in title compound (I) is located on atom O1, thus the phenol-imine tautomer is favored over the keto-amine form, as indicated by the C2—O1, C8—N1, C1—C8 and C1—C2 bond lengths (Fig. 1 and Table 2). The O1—C2 bond length of 1.351 (2) Å indicates single-bond character, whereas the N1—C8 bond length of 1.283 (2) Å indicates double-bond character. A similar work was observed for X-ray crystal and computational structural study of (E)-2-[(4-bromophenyl)iminomethyl] -4-methoxyphenol [C—O=1.358 (4) Å, C—N= 1.287 (4) Å, Özek et al., 2007].It is known that π interactions exist (Table 1) (Fig. 2).
may exhibit thermochromism or depending on the planarity or non-planarity of the molecule, respectively. Therefore, one can expect photochromic properties in (I) caused by non-planarity of the molecules; the dihedral angle between rings A(C1—C6) and B ring (C9—C14) is 48.17 (1) °. The intramolecular O—H···N hydrogen bond (Table 1) results in the formation of six-membered ring and it generates an S(6) ring motif. The O1···N1 distance of 2.614 (2) Å is comparable to those observed for analogous hydrogen bonds in "Three (E)-2-[(bromophenyl)iminomethyl]-4-methoxyphenols" [2.603 (2) Å, 2.638 (7) Å, 2.577 (4) Å; Özek et al., 2007]. In the C—H···The present work is part of a structural study of ǧlu et al. (2007); Albayrak et al. (2005). For related structures, see: Özek et al. (2009); Özek et al. (2007).
see: Özek et al. (2007); OdabaşoData 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).C14H12FNO2 | F(000) = 256 |
Mr = 245.25 | Dx = 1.352 Mg m−3 |
Monoclinic, Pc | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P -2yc | Cell parameters from 11108 reflections |
a = 13.1806 (7) Å | θ = 1.6–28.0° |
b = 7.1785 (5) Å | µ = 0.10 mm−1 |
c = 6.4297 (3) Å | T = 296 K |
β = 97.967 (4)° | Plate, yellow |
V = 602.49 (6) Å3 | 0.68 × 0.48 × 0.17 mm |
Z = 2 |
Stoe IPDS II diffractometer | 1399 independent reflections |
Radiation source: fine-focus sealed tube | 1273 reflections with I > 2σ(I) |
Plane graphite monochromator | Rint = 0.037 |
Detector resolution: 6.67 pixels mm-1 | θmax = 27.6°, θmin = 2.8° |
ω–scan rotation method | h = −17→17 |
Absorption correction: integration (X-RED32; Stoe & Cie, 2002) | k = −9→9 |
Tmin = 0.932, Tmax = 0.985 | l = −8→8 |
6287 measured reflections |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.035 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.104 | w = 1/[σ2(Fo2) + (0.0672P)2 + 0.0142P] where P = (Fo2 + 2Fc2)/3 |
S = 1.09 | (Δ/σ)max < 0.001 |
1399 reflections | Δρmax = 0.20 e Å−3 |
168 parameters | Δρmin = −0.11 e Å−3 |
3 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.022 (7) |
C14H12FNO2 | V = 602.49 (6) Å3 |
Mr = 245.25 | Z = 2 |
Monoclinic, Pc | Mo Kα radiation |
a = 13.1806 (7) Å | µ = 0.10 mm−1 |
b = 7.1785 (5) Å | T = 296 K |
c = 6.4297 (3) Å | 0.68 × 0.48 × 0.17 mm |
β = 97.967 (4)° |
Stoe IPDS II diffractometer | 1399 independent reflections |
Absorption correction: integration (X-RED32; Stoe & Cie, 2002) | 1273 reflections with I > 2σ(I) |
Tmin = 0.932, Tmax = 0.985 | Rint = 0.037 |
6287 measured reflections |
R[F2 > 2σ(F2)] = 0.035 | 3 restraints |
wR(F2) = 0.104 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.09 | Δρmax = 0.20 e Å−3 |
1399 reflections | Δρmin = −0.11 e Å−3 |
168 parameters |
Experimental. 237 frames, detector distance = 100 mm |
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 | ||
C1 | 0.67815 (17) | 0.7844 (3) | 0.5679 (3) | 0.0430 (5) | |
C2 | 0.68722 (16) | 0.7118 (3) | 0.3666 (3) | 0.0452 (5) | |
C3 | 0.78232 (18) | 0.6912 (3) | 0.3009 (4) | 0.0473 (5) | |
H3 | 0.7878 | 0.6379 | 0.1711 | 0.057* | |
C4 | 0.86907 (16) | 0.7504 (3) | 0.4299 (3) | 0.0448 (5) | |
C5 | 0.86142 (16) | 0.8247 (3) | 0.6292 (3) | 0.0482 (5) | |
H5 | 0.9199 | 0.8648 | 0.7153 | 0.058* | |
C6 | 0.76785 (16) | 0.8378 (3) | 0.6958 (3) | 0.0472 (5) | |
H6 | 0.7637 | 0.8834 | 0.8297 | 0.057* | |
C7 | 0.9809 (2) | 0.6644 (5) | 0.1854 (5) | 0.0735 (7) | |
H7A | 0.9579 | 0.5374 | 0.1792 | 0.088* | |
H7B | 1.0525 | 0.6683 | 0.1720 | 0.088* | |
H7C | 0.9429 | 0.7339 | 0.0730 | 0.088* | |
C8 | 0.58033 (17) | 0.7980 (3) | 0.6444 (3) | 0.0465 (5) | |
H8 | 0.5785 | 0.8356 | 0.7822 | 0.056* | |
C9 | 0.40316 (17) | 0.7582 (3) | 0.6157 (4) | 0.0456 (5) | |
C10 | 0.39603 (19) | 0.6839 (3) | 0.8123 (4) | 0.0539 (5) | |
H10 | 0.4544 | 0.6382 | 0.8942 | 0.065* | |
C11 | 0.3028 (2) | 0.6775 (4) | 0.8871 (4) | 0.0606 (6) | |
H11 | 0.2976 | 0.6270 | 1.0184 | 0.073* | |
C12 | 0.21810 (19) | 0.7470 (4) | 0.7637 (5) | 0.0598 (6) | |
C13 | 0.22135 (19) | 0.8207 (4) | 0.5678 (4) | 0.0607 (6) | |
H13 | 0.1625 | 0.8667 | 0.4877 | 0.073* | |
C14 | 0.31454 (17) | 0.8245 (4) | 0.4932 (4) | 0.0522 (5) | |
H14 | 0.3185 | 0.8717 | 0.3599 | 0.063* | |
N1 | 0.49593 (14) | 0.7598 (2) | 0.5277 (3) | 0.0485 (5) | |
O1 | 0.60343 (14) | 0.6613 (3) | 0.2332 (3) | 0.0631 (5) | |
O2 | 0.96531 (13) | 0.7433 (3) | 0.3800 (3) | 0.0561 (4) | |
F1 | 0.12629 (15) | 0.7419 (3) | 0.8381 (4) | 0.0922 (6) | |
H1 | 0.553 (2) | 0.676 (4) | 0.294 (5) | 0.079 (10)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0418 (10) | 0.0416 (11) | 0.0453 (12) | −0.0015 (8) | 0.0053 (8) | −0.0006 (8) |
C2 | 0.0420 (11) | 0.0492 (11) | 0.0433 (12) | −0.0009 (8) | 0.0020 (9) | −0.0016 (8) |
C3 | 0.0479 (11) | 0.0539 (12) | 0.0406 (10) | −0.0011 (9) | 0.0075 (8) | −0.0044 (9) |
C4 | 0.0433 (11) | 0.0459 (10) | 0.0459 (12) | 0.0014 (8) | 0.0083 (9) | 0.0045 (9) |
C5 | 0.0439 (11) | 0.0547 (11) | 0.0443 (11) | −0.0041 (8) | −0.0003 (9) | −0.0031 (9) |
C6 | 0.0493 (12) | 0.0510 (11) | 0.0403 (11) | −0.0007 (8) | 0.0034 (9) | −0.0047 (8) |
C7 | 0.0540 (14) | 0.109 (2) | 0.0612 (15) | −0.0001 (14) | 0.0216 (11) | −0.0148 (14) |
C8 | 0.0456 (11) | 0.0472 (11) | 0.0467 (11) | 0.0012 (8) | 0.0068 (9) | −0.0022 (8) |
C9 | 0.0427 (11) | 0.0453 (11) | 0.0492 (12) | −0.0012 (8) | 0.0073 (9) | −0.0028 (8) |
C10 | 0.0521 (12) | 0.0561 (12) | 0.0527 (13) | 0.0052 (10) | 0.0051 (10) | 0.0028 (10) |
C11 | 0.0668 (16) | 0.0630 (13) | 0.0541 (13) | −0.0032 (12) | 0.0158 (12) | 0.0027 (11) |
C12 | 0.0453 (13) | 0.0678 (14) | 0.0692 (17) | −0.0077 (10) | 0.0184 (12) | −0.0090 (12) |
C13 | 0.0435 (12) | 0.0705 (15) | 0.0663 (17) | −0.0007 (11) | 0.0008 (11) | −0.0035 (12) |
C14 | 0.0461 (12) | 0.0593 (12) | 0.0503 (13) | −0.0003 (9) | 0.0041 (9) | 0.0013 (10) |
N1 | 0.0415 (10) | 0.0532 (10) | 0.0509 (11) | 0.0016 (8) | 0.0063 (8) | −0.0004 (8) |
O1 | 0.0438 (8) | 0.0922 (12) | 0.0515 (9) | −0.0082 (8) | 0.0007 (7) | −0.0194 (9) |
O2 | 0.0420 (8) | 0.0746 (12) | 0.0529 (9) | −0.0021 (7) | 0.0108 (7) | −0.0033 (8) |
F1 | 0.0568 (10) | 0.1257 (16) | 0.1005 (15) | −0.0092 (10) | 0.0334 (9) | −0.0025 (11) |
C1—C6 | 1.397 (3) | C8—N1 | 1.282 (3) |
C1—C2 | 1.416 (3) | C8—H8 | 0.9300 |
C1—C8 | 1.445 (3) | C9—C10 | 1.387 (3) |
C2—O1 | 1.351 (3) | C9—C14 | 1.399 (3) |
C2—C3 | 1.385 (3) | C9—N1 | 1.417 (3) |
C3—C4 | 1.383 (3) | C10—C11 | 1.381 (3) |
C3—H3 | 0.9300 | C10—H10 | 0.9300 |
C4—O2 | 1.352 (3) | C11—C12 | 1.371 (4) |
C4—C5 | 1.404 (3) | C11—H11 | 0.9300 |
C5—C6 | 1.364 (3) | C12—F1 | 1.362 (3) |
C5—H5 | 0.9300 | C12—C13 | 1.372 (4) |
C6—H6 | 0.9300 | C13—C14 | 1.379 (3) |
C7—O2 | 1.414 (3) | C13—H13 | 0.9300 |
C7—H7A | 0.9600 | C14—H14 | 0.9300 |
C7—H7B | 0.9600 | O1—H1 | 0.824 (19) |
C7—H7C | 0.9600 | ||
C6—C1—C2 | 117.86 (19) | N1—C8—C1 | 121.93 (19) |
C6—C1—C8 | 120.22 (19) | N1—C8—H8 | 119.0 |
C2—C1—C8 | 121.89 (18) | C1—C8—H8 | 119.0 |
O1—C2—C3 | 118.2 (2) | C10—C9—C14 | 119.1 (2) |
O1—C2—C1 | 120.96 (19) | C10—C9—N1 | 122.6 (2) |
C3—C2—C1 | 120.86 (18) | C14—C9—N1 | 118.2 (2) |
C4—C3—C2 | 119.5 (2) | C11—C10—C9 | 120.4 (2) |
C4—C3—H3 | 120.3 | C11—C10—H10 | 119.8 |
C2—C3—H3 | 120.3 | C9—C10—H10 | 119.8 |
O2—C4—C3 | 124.8 (2) | C12—C11—C10 | 118.6 (3) |
O2—C4—C5 | 114.78 (19) | C12—C11—H11 | 120.7 |
C3—C4—C5 | 120.4 (2) | C10—C11—H11 | 120.7 |
C6—C5—C4 | 119.69 (19) | F1—C12—C11 | 118.6 (3) |
C6—C5—H5 | 120.2 | F1—C12—C13 | 118.4 (3) |
C4—C5—H5 | 120.2 | C11—C12—C13 | 123.0 (2) |
C5—C6—C1 | 121.6 (2) | C12—C13—C14 | 118.0 (2) |
C5—C6—H6 | 119.2 | C12—C13—H13 | 121.0 |
C1—C6—H6 | 119.2 | C14—C13—H13 | 121.0 |
O2—C7—H7A | 109.5 | C13—C14—C9 | 120.8 (2) |
O2—C7—H7B | 109.5 | C13—C14—H14 | 119.6 |
H7A—C7—H7B | 109.5 | C9—C14—H14 | 119.6 |
O2—C7—H7C | 109.5 | C8—N1—C9 | 119.66 (17) |
H7A—C7—H7C | 109.5 | C2—O1—H1 | 108 (3) |
H7B—C7—H7C | 109.5 | C4—O2—C7 | 118.77 (19) |
C6—C1—C2—O1 | −178.6 (2) | C14—C9—C10—C11 | −0.7 (3) |
C8—C1—C2—O1 | 3.5 (3) | N1—C9—C10—C11 | −176.9 (2) |
C6—C1—C2—C3 | 1.3 (3) | C9—C10—C11—C12 | −0.4 (4) |
C8—C1—C2—C3 | −176.6 (2) | C10—C11—C12—F1 | −179.5 (2) |
O1—C2—C3—C4 | 176.8 (2) | C10—C11—C12—C13 | 0.9 (4) |
C1—C2—C3—C4 | −3.1 (3) | F1—C12—C13—C14 | −179.7 (2) |
C2—C3—C4—O2 | −177.68 (19) | C11—C12—C13—C14 | −0.1 (4) |
C2—C3—C4—C5 | 2.3 (3) | C12—C13—C14—C9 | −1.1 (4) |
O2—C4—C5—C6 | −179.79 (19) | C10—C9—C14—C13 | 1.5 (3) |
C3—C4—C5—C6 | 0.2 (3) | N1—C9—C14—C13 | 177.9 (2) |
C4—C5—C6—C1 | −2.1 (3) | C1—C8—N1—C9 | 174.01 (17) |
C2—C1—C6—C5 | 1.3 (3) | C10—C9—N1—C8 | −40.8 (3) |
C8—C1—C6—C5 | 179.26 (19) | C14—C9—N1—C8 | 143.0 (2) |
C6—C1—C8—N1 | 176.2 (2) | C3—C4—O2—C7 | −2.2 (3) |
C2—C1—C8—N1 | −5.9 (3) | C5—C4—O2—C7 | 177.8 (2) |
Cg1 and Cg2 are the centroids of C1—C6 and C9—C14 rings, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N1 | 0.82 (2) | 1.87 (2) | 2.615 (3) | 150 (3) |
C6—H6···Cg1i | 0.93 | 2.73 | 3.4363 | 133 |
C11—H11···Cg2ii | 0.93 | 2.93 | 3.6414 | 134 |
C14—H14···Cg2iii | 0.93 | 2.91 | 3.6076 | 133 |
Symmetry codes: (i) x, −y, z+1/2; (ii) x, −y+1, z+1/2; (iii) x, −y, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | C14H12FNO2 |
Mr | 245.25 |
Crystal system, space group | Monoclinic, Pc |
Temperature (K) | 296 |
a, b, c (Å) | 13.1806 (7), 7.1785 (5), 6.4297 (3) |
β (°) | 97.967 (4) |
V (Å3) | 602.49 (6) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.68 × 0.48 × 0.17 |
Data collection | |
Diffractometer | Stoe IPDS II |
Absorption correction | Integration (X-RED32; Stoe & Cie, 2002) |
Tmin, Tmax | 0.932, 0.985 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6287, 1399, 1273 |
Rint | 0.037 |
(sin θ/λ)max (Å−1) | 0.651 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.035, 0.104, 1.09 |
No. of reflections | 1399 |
No. of parameters | 168 |
No. of restraints | 3 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.20, −0.11 |
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).
Cg1 and Cg2 are the centroids of C1—C6 and C9—C14 rings, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N1 | 0.824 (19) | 1.87 (2) | 2.615 (3) | 150 (3) |
C6—H6···Cg1i | 0.93 | 2.73 | 3.4363 | 133.00 |
C11—H11···Cg2ii | 0.93 | 2.93 | 3.6414 | 134.00 |
C14—H14···Cg2iii | 0.93 | 2.91 | 3.6076 | 133.00 |
Symmetry codes: (i) x, −y, z+1/2; (ii) x, −y+1, z+1/2; (iii) x, −y, z−1/2. |
Acknowledgements
The authors acknowledge the Faculty of Arts and Sciences, Ondokuz Mayıs University, Turkey, for the use of the Stoe IPDS II diffractometer (purchased under grant F.279 of the University Research Fund).
References
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The present work is part of a structural study of Schiff bases (Özek et al., 2009; Özek et al., 2007) and we report here the structure of (E)-2-(4-Fluorophenylimino)methyl-5-methoxyphenol, (I).
The ortho-hydroxy Schiff Bases that show tautomerism by the intramolecular proton transfer from an oxygen atom to the neighboring nitrogen atom are important compounds. These compounds can exist in three different structures as enol, keto or zwitterionic forms in the solid state. The title compound (I) consists of two aromatic rings (C1 to C6 and C9 to C14), and an imino frame (C9—N1—C8—C1). In (E)-2-(4-Fluorophenylimino)methyl- 5-methoxyphenol which adopts an E configuration about the C=N double bond, dihedral angle between the aromatic rings is 48.17 (1) °. The H atom in title compound (I) is located on atom O1, thus the phenol-imine tautomer is favored over the keto-amine form, as indicated by the C2—O1, C8—N1, C1—C8 and C1—C2 bond lengths (Fig. 1 and Table 2). The O1—C2 bond length of 1.351 (2) Å indicates single-bond character, whereas the N1—C8 bond length of 1.283 (2) Å indicates double-bond character. A similar work was observed for X-ray crystal and computational structural study of (E)-2-[(4-bromophenyl)iminomethyl] -4-methoxyphenol [C—O=1.358 (4) Å, C—N= 1.287 (4) Å, Özek et al., 2007].
It is known that Schiff bases may exhibit thermochromism or photochromism, depending on the planarity or non-planarity of the molecule, respectively. Therefore, one can expect photochromic properties in (I) caused by non-planarity of the molecules; the dihedral angle between rings A(C1—C6) and B ring (C9—C14) is 48.17 (1) °. The intramolecular O—H···N hydrogen bond (Table 1) results in the formation of six-membered ring and it generates an S(6) ring motif. The O1···N1 distance of 2.614 (2) Å is comparable to those observed for analogous hydrogen bonds in "Three (E)-2-[(bromophenyl)iminomethyl]-4-methoxyphenols" [2.603 (2) Å, 2.638 (7) Å, 2.577 (4) Å; Özek et al., 2007]. In the crystal structure, C—H···π interactions exist (Table 1) (Fig. 2).