organic compounds
2-Methyl-6-[2-(trifluoromethyl)phenyliminomethyl]phenol
aDepartment of Physics, Faculty of Arts & Science, Ondokuz Mayıs University, TR-55139 Kurupelit-Samsun, Turkey
*Correspondence e-mail: htanak@omu.edu.tr
The title compound, C15H12F3NO, is a Schiff base which adopts the phenol–imine tautomeric form in the solid state. The dihedral angle between the aromatic rings is 38.79 (5)°. The molecular structure is stabilized by an intramolecular O—H⋯N hydrogen bond, which generates an S(6) ring. In addition, there is an intramolecular short C—H⋯F contact.
Related literature
For the biological properties of et al. (1979); Layer (1963); Ingold (1969) Taggi et al. (2002); Aydoğan et al. (2001). Schiff base compounds can be classified by their photochromic and thermochromic characteristics, see: Cohen et al. (1964); Moustakali-Mavridis et al. (1978). For the graph-set description of hydrogen bonds, see: Bernstein et al. (1995. For a related structure, see: Temel et al. (2007).
see: BartonExperimental
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/S1600536809044560/bt5114sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536809044560/bt5114Isup2.hkl
A solution of 3-methylsalicylaldehyde (0.0233 g, 0.1711 mmol) in ethanol (10 ml) was added to a solution of 2-Triflouromethylaniline (0.0275 g, 0.1711 mmol) in ethanol (20 ml). The reaction mixture was stirred for 2 h underreflux. Single crystals suitable for X-ray analysis were obtained from ethylalcohol by slow evaporation (yield 69%; m.p.408–410 K).
C-bound H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93–0.96 Å and Uiso(H) = 1.2–1.5Ueq(C). The position of the H1 atom was obtained from a difference map and this atom was refined freely. Friedel pairs were merged in the final
because the value of the parameter (Flack, 1983) is meaningless.Schiff bases, i.e., compounds having a double C=N bond, are used as starting materials in the synthesis of important drugs, such as antibiotics and antiallergic, antiphlogistic, and antitumor substances (Barton et al., 1979; Layer, 1963; Ingold 1969). On the industrial scale, they have a wide range of applications, such as dyes and pigments (Taggi et al., 2002).
have also been employed as ligands for the complexation of metal ions (Aydoğan et al., 2001). There are two characteristic properties of viz. and thermochromism (Cohen et al., 1964). In general, display two possible tautomeric forms, the phenol-imine (OH) and the keto-amine (NH) 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.In the title compound (Fig. 1), the molecular structure is not planar. The dihedral angle between the aromatic ring systems [C1/C6 and C9/C14] is 38.79 (5)°. It is also known that
may exhibit thermochromism depending on the planarity or non-planarity, respectively (Moustakali-Mavridis et al., 1978).The O—H and C=N bond lengths confirm the phenol-imine form of the title compound. These distances agree with the corresponding distances in (E)-3-[2-(Trifluoromethyl)phenyliminomethyl]-benzene-1,2-diol (Temel et al., 2007), which is related structure. The imine group is coplanar with the C1—C6 aromatic ring system as it can be shown by the C2—C1—C8—N1 torsion angle is 1.67 (19)°.The molecular structure is stabilized by intramolecular hydrogen bonds. An intramolecular O1—H1···N1 hydrogen bond (Fig. 1) generates a six-membered ring, producing an S(6) ring motif (Bernstein et al., 1995), resulting in approximate planarity of the molecular skeleton [O···N= 2.6187 (16) Å]. The
is further stabilized by intramolecular C—H···F hydrogen bond, namely C13—H13···F3. And also details of the hydrogen bond is shown in Table 1.For the biological properties of
see: Barton et al. (1979); Layer (1963); Ingold (1969) Taggi et al. (2002); Aydoğan et al. (2001). Schiff base compounds can be classified by their photochromicand thermochromic characteristics, see: Cohen et al. (1964); Moustakali-Mavridis et al. (1978). For the graph-set description of hydrogen bonds, see: Bernstein et al. (1995. For a related structure, see: Temel et al. (2007).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 and 30% probability diplacement ellipsoids. |
C15H12F3NO | F(000) = 576 |
Mr = 279.26 | Dx = 1.422 Mg m−3 |
Orthorhombic, P212121 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2ac 2ab | Cell parameters from 19471 reflections |
a = 8.1634 (3) Å | θ = 1.5–28.0° |
b = 11.8810 (6) Å | µ = 0.12 mm−1 |
c = 13.4469 (7) Å | T = 293 K |
V = 1304.21 (11) Å3 | Prism, light yellow |
Z = 4 | 0.73 × 0.51 × 0.37 mm |
Stoe IPDS II diffractometer | 1565 independent reflections |
Radiation source: fine-focus sealed tube | 1396 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.030 |
Detector resolution: 6.67 pixels mm-1 | θmax = 26.5°, θmin = 2.3° |
rotation method scans | h = −10→10 |
Absorption correction: integration (X-RED32; Stoe & Cie, 2002) | k = −14→14 |
Tmin = 0.943, Tmax = 0.970 | l = −16→16 |
14752 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)] = 0.031 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.081 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.07 | w = 1/[σ2(Fo2) + (0.0562P)2 + 0.0179P] where P = (Fo2 + 2Fc2)/3 |
1565 reflections | (Δ/σ)max < 0.001 |
187 parameters | Δρmax = 0.09 e Å−3 |
0 restraints | Δρmin = −0.15 e Å−3 |
C15H12F3NO | V = 1304.21 (11) Å3 |
Mr = 279.26 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 8.1634 (3) Å | µ = 0.12 mm−1 |
b = 11.8810 (6) Å | T = 293 K |
c = 13.4469 (7) Å | 0.73 × 0.51 × 0.37 mm |
Stoe IPDS II diffractometer | 1565 independent reflections |
Absorption correction: integration (X-RED32; Stoe & Cie, 2002) | 1396 reflections with I > 2σ(I) |
Tmin = 0.943, Tmax = 0.970 | Rint = 0.030 |
14752 measured reflections |
R[F2 > 2σ(F2)] = 0.031 | 0 restraints |
wR(F2) = 0.081 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.07 | Δρmax = 0.09 e Å−3 |
1565 reflections | Δρmin = −0.15 e Å−3 |
187 parameters |
Experimental. 270 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 | 0.5950 (2) | 0.12366 (13) | 0.48589 (13) | 0.0521 (4) | |
C2 | 0.7604 (2) | 0.09829 (14) | 0.46506 (13) | 0.0521 (4) | |
C3 | 0.8634 (3) | 0.05379 (15) | 0.53818 (15) | 0.0589 (5) | |
C4 | 0.7966 (3) | 0.03487 (16) | 0.63136 (16) | 0.0669 (5) | |
H4 | 0.8626 | 0.0039 | 0.6806 | 0.080* | |
C5 | 0.6363 (3) | 0.06007 (18) | 0.65389 (16) | 0.0725 (6) | |
H5 | 0.5960 | 0.0471 | 0.7176 | 0.087* | |
C6 | 0.5366 (3) | 0.10426 (16) | 0.58227 (15) | 0.0653 (5) | |
H6 | 0.4285 | 0.1217 | 0.5977 | 0.078* | |
C7 | 1.0381 (3) | 0.0287 (2) | 0.51468 (19) | 0.0804 (6) | |
H7A | 1.0972 | 0.0979 | 0.5064 | 0.121* | |
H7B | 1.0440 | −0.0144 | 0.4544 | 0.121* | |
H7C | 1.0857 | −0.0137 | 0.5682 | 0.121* | |
C8 | 0.4855 (2) | 0.16517 (13) | 0.41041 (14) | 0.0536 (4) | |
H8 | 0.3783 | 0.1826 | 0.4280 | 0.064* | |
C9 | 0.4144 (2) | 0.21161 (13) | 0.24725 (14) | 0.0525 (4) | |
C10 | 0.2558 (3) | 0.16864 (15) | 0.24564 (17) | 0.0638 (5) | |
H10 | 0.2227 | 0.1181 | 0.2945 | 0.077* | |
C11 | 0.1481 (3) | 0.20022 (18) | 0.1726 (2) | 0.0757 (6) | |
H11 | 0.0427 | 0.1705 | 0.1720 | 0.091* | |
C12 | 0.1946 (3) | 0.27551 (18) | 0.10000 (19) | 0.0747 (6) | |
H12 | 0.1202 | 0.2976 | 0.0514 | 0.090* | |
C13 | 0.3510 (3) | 0.31792 (17) | 0.09962 (16) | 0.0661 (5) | |
H13 | 0.3827 | 0.3681 | 0.0502 | 0.079* | |
C14 | 0.4618 (2) | 0.28640 (13) | 0.17241 (14) | 0.0541 (4) | |
C15 | 0.6310 (3) | 0.33225 (16) | 0.17122 (15) | 0.0625 (5) | |
N1 | 0.53021 (19) | 0.17904 (11) | 0.31975 (11) | 0.0530 (3) | |
O1 | 0.82427 (18) | 0.11539 (13) | 0.37360 (11) | 0.0671 (4) | |
F1 | 0.67184 (18) | 0.38548 (12) | 0.25515 (11) | 0.0888 (4) | |
F2 | 0.74444 (17) | 0.25364 (12) | 0.15746 (12) | 0.0872 (4) | |
F3 | 0.65390 (18) | 0.40802 (13) | 0.09842 (12) | 0.0930 (5) | |
H1 | 0.738 (4) | 0.141 (2) | 0.335 (2) | 0.097 (9)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0552 (10) | 0.0460 (7) | 0.0550 (9) | −0.0031 (7) | 0.0000 (8) | −0.0035 (7) |
C2 | 0.0568 (10) | 0.0468 (7) | 0.0528 (9) | −0.0038 (7) | −0.0010 (8) | −0.0033 (7) |
C3 | 0.0606 (11) | 0.0518 (8) | 0.0644 (11) | −0.0035 (8) | −0.0118 (9) | −0.0052 (8) |
C4 | 0.0800 (15) | 0.0577 (9) | 0.0631 (11) | −0.0075 (9) | −0.0180 (11) | 0.0033 (8) |
C5 | 0.0891 (16) | 0.0757 (11) | 0.0528 (11) | −0.0107 (11) | 0.0015 (11) | 0.0036 (9) |
C6 | 0.0685 (12) | 0.0689 (10) | 0.0584 (10) | −0.0042 (10) | 0.0059 (10) | −0.0013 (9) |
C7 | 0.0621 (13) | 0.0903 (14) | 0.0889 (16) | 0.0081 (11) | −0.0139 (13) | −0.0037 (13) |
C8 | 0.0492 (10) | 0.0487 (7) | 0.0630 (10) | 0.0005 (7) | 0.0041 (8) | −0.0018 (7) |
C9 | 0.0490 (9) | 0.0471 (7) | 0.0613 (10) | 0.0058 (7) | −0.0018 (8) | −0.0009 (7) |
C10 | 0.0527 (11) | 0.0570 (9) | 0.0816 (13) | 0.0005 (8) | −0.0025 (10) | 0.0039 (10) |
C11 | 0.0528 (11) | 0.0695 (11) | 0.1048 (17) | 0.0025 (9) | −0.0140 (12) | −0.0067 (12) |
C12 | 0.0711 (14) | 0.0692 (11) | 0.0837 (14) | 0.0144 (11) | −0.0227 (12) | −0.0005 (11) |
C13 | 0.0706 (13) | 0.0599 (10) | 0.0678 (12) | 0.0109 (9) | −0.0078 (10) | 0.0059 (9) |
C14 | 0.0559 (10) | 0.0478 (7) | 0.0586 (10) | 0.0070 (7) | −0.0011 (8) | −0.0010 (7) |
C15 | 0.0604 (11) | 0.0620 (10) | 0.0652 (11) | 0.0010 (8) | 0.0044 (9) | 0.0072 (9) |
N1 | 0.0483 (8) | 0.0525 (7) | 0.0583 (8) | 0.0029 (6) | −0.0018 (7) | 0.0025 (6) |
O1 | 0.0530 (8) | 0.0886 (9) | 0.0596 (8) | 0.0050 (7) | 0.0044 (7) | 0.0051 (7) |
F1 | 0.0835 (10) | 0.0967 (9) | 0.0861 (9) | −0.0323 (8) | 0.0002 (8) | −0.0127 (7) |
F2 | 0.0565 (7) | 0.0926 (8) | 0.1124 (11) | 0.0123 (7) | 0.0131 (7) | 0.0079 (8) |
F3 | 0.0857 (9) | 0.0928 (8) | 0.1004 (10) | −0.0116 (8) | 0.0083 (8) | 0.0376 (8) |
C1—C6 | 1.400 (3) | C9—C10 | 1.392 (3) |
C1—C2 | 1.411 (3) | C9—C14 | 1.397 (2) |
C1—C8 | 1.440 (3) | C9—N1 | 1.412 (2) |
C2—O1 | 1.351 (2) | C10—C11 | 1.371 (3) |
C2—C3 | 1.398 (3) | C10—H10 | 0.9300 |
C3—C4 | 1.385 (3) | C11—C12 | 1.377 (3) |
C3—C7 | 1.491 (3) | C11—H11 | 0.9300 |
C4—C5 | 1.376 (3) | C12—C13 | 1.373 (3) |
C4—H4 | 0.9300 | C12—H12 | 0.9300 |
C5—C6 | 1.366 (3) | C13—C14 | 1.385 (3) |
C5—H5 | 0.9300 | C13—H13 | 0.9300 |
C6—H6 | 0.9300 | C14—C15 | 1.484 (3) |
C7—H7A | 0.9600 | C15—F2 | 1.328 (2) |
C7—H7B | 0.9600 | C15—F1 | 1.336 (2) |
C7—H7C | 0.9600 | C15—F3 | 1.343 (2) |
C8—N1 | 1.283 (2) | O1—H1 | 0.93 (3) |
C8—H8 | 0.9300 | ||
C6—C1—C2 | 118.34 (18) | C10—C9—C14 | 118.66 (18) |
C6—C1—C8 | 119.82 (18) | C10—C9—N1 | 122.19 (17) |
C2—C1—C8 | 121.82 (16) | C14—C9—N1 | 119.10 (17) |
O1—C2—C3 | 117.71 (18) | C11—C10—C9 | 120.5 (2) |
O1—C2—C1 | 121.19 (17) | C11—C10—H10 | 119.8 |
C3—C2—C1 | 121.10 (18) | C9—C10—H10 | 119.8 |
C4—C3—C2 | 117.4 (2) | C10—C11—C12 | 120.6 (2) |
C4—C3—C7 | 122.4 (2) | C10—C11—H11 | 119.7 |
C2—C3—C7 | 120.1 (2) | C12—C11—H11 | 119.7 |
C5—C4—C3 | 122.6 (2) | C13—C12—C11 | 119.8 (2) |
C5—C4—H4 | 118.7 | C13—C12—H12 | 120.1 |
C3—C4—H4 | 118.7 | C11—C12—H12 | 120.1 |
C6—C5—C4 | 119.7 (2) | C12—C13—C14 | 120.4 (2) |
C6—C5—H5 | 120.2 | C12—C13—H13 | 119.8 |
C4—C5—H5 | 120.2 | C14—C13—H13 | 119.8 |
C5—C6—C1 | 120.9 (2) | C13—C14—C9 | 120.02 (19) |
C5—C6—H6 | 119.6 | C13—C14—C15 | 120.06 (17) |
C1—C6—H6 | 119.6 | C9—C14—C15 | 119.91 (16) |
C3—C7—H7A | 109.5 | F2—C15—F1 | 106.04 (18) |
C3—C7—H7B | 109.5 | F2—C15—F3 | 105.81 (17) |
H7A—C7—H7B | 109.5 | F1—C15—F3 | 105.28 (16) |
C3—C7—H7C | 109.5 | F2—C15—C14 | 113.09 (15) |
H7A—C7—H7C | 109.5 | F1—C15—C14 | 113.39 (17) |
H7B—C7—H7C | 109.5 | F3—C15—C14 | 112.55 (17) |
N1—C8—C1 | 122.48 (18) | C8—N1—C9 | 120.06 (16) |
N1—C8—H8 | 118.8 | C2—O1—H1 | 105.5 (18) |
C1—C8—H8 | 118.8 | ||
C6—C1—C2—O1 | −179.82 (16) | C9—C10—C11—C12 | −0.5 (3) |
C8—C1—C2—O1 | 2.1 (2) | C10—C11—C12—C13 | 1.2 (3) |
C6—C1—C2—C3 | 0.7 (2) | C11—C12—C13—C14 | −0.7 (3) |
C8—C1—C2—C3 | −177.39 (15) | C12—C13—C14—C9 | −0.4 (3) |
O1—C2—C3—C4 | −179.06 (16) | C12—C13—C14—C15 | 179.73 (18) |
C1—C2—C3—C4 | 0.5 (2) | C10—C9—C14—C13 | 1.1 (2) |
O1—C2—C3—C7 | 1.1 (3) | N1—C9—C14—C13 | 178.90 (16) |
C1—C2—C3—C7 | −179.41 (17) | C10—C9—C14—C15 | −179.04 (17) |
C2—C3—C4—C5 | −1.2 (3) | N1—C9—C14—C15 | −1.3 (2) |
C7—C3—C4—C5 | 178.6 (2) | C13—C14—C15—F2 | −116.15 (19) |
C3—C4—C5—C6 | 0.8 (3) | C9—C14—C15—F2 | 64.0 (2) |
C4—C5—C6—C1 | 0.4 (3) | C13—C14—C15—F1 | 123.08 (19) |
C2—C1—C6—C5 | −1.1 (3) | C9—C14—C15—F1 | −56.8 (2) |
C8—C1—C6—C5 | 176.98 (17) | C13—C14—C15—F3 | 3.7 (3) |
C6—C1—C8—N1 | −176.38 (16) | C9—C14—C15—F3 | −176.13 (16) |
C2—C1—C8—N1 | 1.6 (3) | C1—C8—N1—C9 | 175.06 (14) |
C14—C9—C10—C11 | −0.7 (3) | C10—C9—N1—C8 | −39.7 (2) |
N1—C9—C10—C11 | −178.38 (17) | C14—C9—N1—C8 | 142.65 (17) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N1 | 0.93 (3) | 1.77 (3) | 2.619 (2) | 151 (3) |
C13—H13···F3 | 0.93 | 2.36 | 2.694 (3) | 101 |
Experimental details
Crystal data | |
Chemical formula | C15H12F3NO |
Mr | 279.26 |
Crystal system, space group | Orthorhombic, P212121 |
Temperature (K) | 293 |
a, b, c (Å) | 8.1634 (3), 11.8810 (6), 13.4469 (7) |
V (Å3) | 1304.21 (11) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.12 |
Crystal size (mm) | 0.73 × 0.51 × 0.37 |
Data collection | |
Diffractometer | Stoe IPDS II |
Absorption correction | Integration (X-RED32; Stoe & Cie, 2002) |
Tmin, Tmax | 0.943, 0.970 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 14752, 1565, 1396 |
Rint | 0.030 |
(sin θ/λ)max (Å−1) | 0.628 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.031, 0.081, 1.07 |
No. of reflections | 1565 |
No. of parameters | 187 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.09, −0.15 |
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).
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N1 | 0.93 (3) | 1.77 (3) | 2.619 (2) | 151 (3) |
C13—H13···F3 | 0.93 | 2.36 | 2.694 (3) | 101.2 |
Acknowledgements
This study was supported financially by the Research Center of Ondokuz Mayıs University (Project No. F-476). 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 No. F279 of the University Research Fund).
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Temel, E., Albayrak, Ç., Odabaşoğlu, M. & Büyükgüngör, O. (2007). Acta Cryst. E63, o374–o376. Web of Science CSD CrossRef IUCr Journals Google Scholar
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Schiff bases, i.e., compounds having a double C=N bond, are used as starting materials in the synthesis of important drugs, such as antibiotics and antiallergic, antiphlogistic, and antitumor substances (Barton et al., 1979; Layer, 1963; Ingold 1969). On the industrial scale, they have a wide range of applications, such as dyes and pigments (Taggi et al., 2002). Schiff bases have also been employed as ligands for the complexation of metal ions (Aydoğan et al., 2001). There are two characteristic properties of Schiff bases, viz. Photochromism and thermochromism (Cohen et al., 1964). In general, Schiff bases display two possible tautomeric forms, the phenol-imine (OH) and the keto-amine (NH) 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.
In the title compound (Fig. 1), the molecular structure is not planar. The dihedral angle between the aromatic ring systems [C1/C6 and C9/C14] is 38.79 (5)°. It is also known that Schiff bases may exhibit thermochromism depending on the planarity or non-planarity, respectively (Moustakali-Mavridis et al., 1978).The O—H and C=N bond lengths confirm the phenol-imine form of the title compound. These distances agree with the corresponding distances in (E)-3-[2-(Trifluoromethyl)phenyliminomethyl]-benzene-1,2-diol (Temel et al., 2007), which is related structure. The imine group is coplanar with the C1—C6 aromatic ring system as it can be shown by the C2—C1—C8—N1 torsion angle is 1.67 (19)°.
The molecular structure is stabilized by intramolecular hydrogen bonds. An intramolecular O1—H1···N1 hydrogen bond (Fig. 1) generates a six-membered ring, producing an S(6) ring motif (Bernstein et al., 1995), resulting in approximate planarity of the molecular skeleton [O···N= 2.6187 (16) Å]. The crystal structure is further stabilized by intramolecular C—H···F hydrogen bond, namely C13—H13···F3. And also details of the hydrogen bond is shown in Table 1.