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ISSN: 2056-9890

(E)-2-[(3-Fluoro­phen­yl)imino­meth­yl]-4-(tri­fluoro­meth­­oxy)phenol

aDepartment of Physics, Faculty of Arts & Science, Ondokuz Mayıs University, TR-55139 Kurupelit-Samsun, Turkey, and bDepartment of Chemistry, Faculty of Arts & Science, Ondokuz Mayıs University, 55139 Samsun, Turkey
*Correspondence e-mail: gokhana@omu.edu.tr

(Received 6 January 2010; accepted 25 January 2010; online 3 February 2010)

The title compound, C14H9F4NO2, is a Schiff base which adopts the phenol–imine tautomeric form in the solid state. The H atom is 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 2.14 (13)°.

Related literature

Schiff base compounds can be classified by their photochromic and thermochromic characteristics, see: Calligaris et al. (1972[Calligaris, M., Nardin, G. & Randaccio, L. (1972). Coord. Chem. Rev. 7, 385-403.]); Cohen et al. (1964[Cohen, M. D., Schmidt, G. M. J. & Flavian, S. (1964). J. Chem. Soc. pp. 2041-2051.]); Hadjoudis et al. (1987[Hadjoudis, E., Vitterakis, M., Moustakali, I. & Mavridis, I. (1987). Tetrahedron, 43, 1345-1360.]). For Schiff base tautomerism,see: Şahin et al. (2005[Şahin, O., Albayrak, C., Odabaşoğlu, M. & Büyükgüngör, O. (2005). Acta Cryst. E61, o2859-o2861.]).

[Scheme 1]

Experimental

Crystal data
  • C14H9F4NO2

  • Mr = 299.22

  • Monoclinic, P 21 /c

  • a = 14.223 (2) Å

  • b = 7.0894 (6) Å

  • c = 13.2479 (19) Å

  • β = 100.910 (11)°

  • V = 1311.7 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.14 mm−1

  • T = 296 K

  • 0.72 × 0.34 × 0.07 mm

Data collection
  • Stoe IPDS-II diffractometer

  • Absorption correction: integration (X-RED32; Stoe & Cie, 2002[Stoe & Cie (2002). X-AREA and X-RED32. Stoe & Cie, Darmstadt, Germany.]) Tmin = 0.929, Tmax = 0.985

  • 8512 measured reflections

  • 2581 independent reflections

  • 1261 reflections with I > 2σ(I)

  • Rint = 0.063

Refinement
  • R[F2 > 2σ(F2)] = 0.057

  • wR(F2) = 0.133

  • S = 1.01

  • 2581 reflections

  • 222 parameters

  • 66 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.12 e Å−3

  • Δρmin = −0.14 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1⋯N1 0.91 (5) 1.81 (5) 2.618 (3) 146 (4)

Data collection: X-AREA (Stoe & Cie, 2002[Stoe & Cie (2002). X-AREA and X-RED32. Stoe & Cie, Darmstadt, Germany.]); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2002[Stoe & Cie (2002). X-AREA and X-RED32. Stoe & Cie, Darmstadt, Germany.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

Schiff bases have been extensively used as ligands in the field of coordination chemistry (Calligaris et al., 1972). Schiff base compounds can be classified by their photochromic and thermochromic characteristics (Cohen et al., 1964). These properties result from proton transfer from the hydroxyl O atom to the imine N atom (Hadjoudis et al., 1987). There are two types of intramolecular hydrogen bonds in Schiff bases, which may be stabilized either in keto-amine (N-H···O hydrogen bond)(Şahin et al., 2005) or phenol-imine (N···H-O hydrogen bond) tautomeric forms (Hadjoudis et al., 1987). The present X-ray investigation shows that the title compound is a Schiff base and exists in the phenol-imine form in the solid-state.

An ORTEP-3 (Farrugia, 1997) plot of the molecule of (I) is shown in Fig.1. The N1-C7 bond length of 1.269 (5) Å is typical of a double bond. The dihedral angle between the C1-C7 and C8-C13 benzene rings is 2.14 (13)° and the compound is thus almost planar. The compound shows a strong intramolecular hydrogen bond (O1-H1···N1).

Related literature top

Schiff base compounds can be classified by their photochromic and thermochromic characteristics, see: Calligaris et al. (1972); Cohen et al. (1964); Hadjoudis et al. (1987). For Schiff base tautomerism,see: Şahin et al. (2005).

Experimental top

The compound (E)-2-((3-fluorophenylimino)methyl)-4-(trifluoromethoxy) phenol was prepared by reflux a mixture of a solution containing 2-Hydroxy-5-(trifluoromethoxy)benzaldehyde (0.010 g; 0.1 mmol) in 20 ml ethanol and a solution containing 3-Fluoroaniline (0.0111 g; 0.1 mmol) in 20 ml ethanol. The reaction mixture was stirred for 1 hour reflux. The crystals of (E)-2-((3-fluorophenylimino)methyl)-4-(trifluoromethoxy) phenol for X-ray analysis were obtained from ethylacetate by slow evaporation (yield, 72%; m.p. 360-363 K).

Refinement top

The H atom bonded to O1 was refined freely. All other H atoms were placed in calculated positions and constrained to ride on their parent atoms, with C—H = 0.93 Å and Uiso(H) = 1.2 Ueq(C). The CF3 group showed rotational disorder. For atoms F1A, F2A and F3A the site occupancy factor is 0.288 (17) and for F1B, F2B and F3B the site occupancy factor is 0.712 (17). The disorder was refined using the restraint commands DFIX, ISOR and SIMU.

Computing details top

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: 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).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii.
(E)-2-[(3-Fluorophenyl)iminomethyl]-4-(trifluoromethoxy)phenol top
Crystal data top
C14H9F4NO2F(000) = 608
Mr = 299.22Dx = 1.515 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 8512 reflections
a = 14.223 (2) Åθ = 1.6–28.5°
b = 7.0894 (6) ŵ = 0.14 mm1
c = 13.2479 (19) ÅT = 296 K
β = 100.910 (11)°Prism., yellow
V = 1311.7 (3) Å30.72 × 0.34 × 0.07 mm
Z = 4
Data collection top
Stoe IPDS-II
diffractometer
2581 independent reflections
Radiation source: fine-focus sealed tube1261 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.063
Detector resolution: 6.67 pixels mm-1θmax = 26.0°, θmin = 2.9°
ω scansh = 1717
Absorption correction: integration
(X-RED32; Stoe & Cie, 2002)
k = 88
Tmin = 0.929, Tmax = 0.985l = 1616
8512 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.057Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.133H atoms treated by a mixture of independent and constrained refinement
S = 1.01 w = 1/[σ2(Fo2) + (0.0516P)2]
where P = (Fo2 + 2Fc2)/3
2581 reflections(Δ/σ)max < 0.001
222 parametersΔρmax = 0.12 e Å3
66 restraintsΔρmin = 0.14 e Å3
Crystal data top
C14H9F4NO2V = 1311.7 (3) Å3
Mr = 299.22Z = 4
Monoclinic, P21/cMo Kα radiation
a = 14.223 (2) ŵ = 0.14 mm1
b = 7.0894 (6) ÅT = 296 K
c = 13.2479 (19) Å0.72 × 0.34 × 0.07 mm
β = 100.910 (11)°
Data collection top
Stoe IPDS-II
diffractometer
2581 independent reflections
Absorption correction: integration
(X-RED32; Stoe & Cie, 2002)
1261 reflections with I > 2σ(I)
Tmin = 0.929, Tmax = 0.985Rint = 0.063
8512 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.05766 restraints
wR(F2) = 0.133H atoms treated by a mixture of independent and constrained refinement
S = 1.01Δρmax = 0.12 e Å3
2581 reflectionsΔρmin = 0.14 e Å3
222 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
C10.6817 (2)0.1145 (4)0.8494 (2)0.0532 (7)
C20.7714 (2)0.1111 (4)0.8217 (2)0.0590 (8)
H20.77570.10330.75260.071*
C30.8530 (2)0.1190 (4)0.8947 (2)0.0609 (8)
C40.8492 (2)0.1262 (5)0.9975 (2)0.0713 (9)
H40.90540.13081.04650.086*
C50.7622 (2)0.1265 (5)1.0275 (2)0.0720 (9)
H50.75950.13081.09710.086*
C60.6781 (2)0.1207 (4)0.9551 (2)0.0578 (7)
C70.5955 (2)0.1111 (4)0.7713 (2)0.0564 (7)
H70.60110.10790.70250.068*
C80.42736 (18)0.1115 (4)0.7176 (2)0.0488 (7)
C90.3428 (2)0.1172 (4)0.7535 (2)0.0626 (8)
H90.34410.12070.82390.075*
C100.2558 (2)0.1176 (4)0.6859 (3)0.0734 (9)
H100.19920.12170.71140.088*
C110.2521 (2)0.1121 (5)0.5813 (3)0.0707 (9)
H110.19410.11320.53510.085*
C120.3369 (2)0.1050 (5)0.5484 (2)0.0666 (8)
C130.4241 (2)0.1054 (4)0.6120 (2)0.0647 (8)
H130.48010.10170.58550.078*
C150.9817 (2)0.2629 (7)0.8394 (3)0.0769 (10)
N10.51254 (17)0.1122 (3)0.79347 (16)0.0539 (6)
O10.59429 (17)0.1222 (4)0.98783 (16)0.0776 (7)
O20.94418 (15)0.1066 (3)0.86652 (18)0.0787 (7)
F1A0.9358 (12)0.389 (2)0.7861 (18)0.117 (5)0.288 (17)
F2A1.0127 (14)0.332 (3)0.9365 (12)0.132 (6)0.288 (17)
F3A1.0594 (14)0.243 (4)0.7992 (19)0.129 (8)0.288 (17)
F1B0.9331 (4)0.3107 (14)0.7446 (5)0.115 (2)0.712 (17)
F2B0.9765 (5)0.4159 (9)0.8941 (7)0.110 (2)0.712 (17)
F3B1.0706 (4)0.2329 (14)0.8333 (7)0.0968 (19)0.712 (17)
F40.33425 (15)0.0950 (4)0.44555 (14)0.1095 (8)
H10.546 (3)0.113 (6)0.932 (4)0.144 (18)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0594 (18)0.0479 (17)0.0537 (16)0.0005 (15)0.0148 (14)0.0009 (15)
C20.066 (2)0.061 (2)0.0517 (16)0.0087 (16)0.0163 (15)0.0009 (16)
C30.0532 (18)0.0606 (19)0.070 (2)0.0119 (16)0.0140 (15)0.0046 (17)
C40.067 (2)0.081 (2)0.062 (2)0.0048 (18)0.0026 (16)0.0132 (19)
C50.074 (2)0.092 (2)0.0498 (17)0.0028 (19)0.0107 (16)0.0077 (18)
C60.0584 (19)0.0612 (19)0.0551 (18)0.0008 (16)0.0139 (14)0.0080 (16)
C70.068 (2)0.0540 (19)0.0500 (17)0.0041 (16)0.0180 (15)0.0042 (15)
C80.0541 (17)0.0393 (15)0.0546 (16)0.0024 (14)0.0145 (14)0.0010 (14)
C90.070 (2)0.061 (2)0.0605 (18)0.0078 (17)0.0220 (16)0.0063 (16)
C100.064 (2)0.074 (2)0.086 (3)0.0009 (18)0.0242 (18)0.006 (2)
C110.060 (2)0.064 (2)0.083 (2)0.0019 (17)0.0011 (17)0.0037 (18)
C120.076 (2)0.072 (2)0.0500 (18)0.0008 (18)0.0055 (16)0.0092 (17)
C130.066 (2)0.079 (2)0.0520 (17)0.0000 (17)0.0191 (15)0.0068 (17)
C150.055 (2)0.096 (3)0.082 (3)0.006 (2)0.018 (2)0.001 (3)
N10.0594 (15)0.0536 (15)0.0496 (13)0.0024 (13)0.0127 (11)0.0003 (12)
O10.0673 (15)0.116 (2)0.0532 (13)0.0080 (14)0.0212 (11)0.0009 (13)
O20.0605 (14)0.0801 (17)0.0998 (17)0.0159 (13)0.0264 (12)0.0094 (14)
F1A0.103 (7)0.096 (7)0.160 (10)0.020 (6)0.044 (8)0.026 (7)
F2A0.128 (9)0.128 (10)0.141 (8)0.039 (7)0.030 (6)0.039 (7)
F3A0.115 (10)0.153 (11)0.136 (12)0.006 (7)0.068 (8)0.001 (8)
F1B0.094 (3)0.164 (5)0.083 (3)0.015 (3)0.008 (2)0.044 (3)
F2B0.113 (4)0.086 (3)0.143 (5)0.019 (3)0.053 (3)0.034 (3)
F3B0.048 (2)0.137 (4)0.110 (4)0.008 (2)0.025 (2)0.011 (3)
F40.1097 (16)0.162 (2)0.0533 (11)0.0061 (15)0.0052 (10)0.0172 (12)
Geometric parameters (Å, º) top
C1—C21.393 (4)C9—C101.383 (4)
C1—C61.411 (4)C9—H90.9300
C1—C71.447 (4)C10—C111.378 (4)
C2—C31.365 (4)C10—H100.9300
C2—H20.9300C11—C121.358 (4)
C3—C41.374 (4)C11—H110.9300
C3—O21.418 (3)C12—F41.358 (3)
C4—C51.369 (4)C12—C131.361 (4)
C4—H40.9300C13—H130.9300
C5—C61.385 (4)C15—F1A1.246 (12)
C5—H50.9300C15—F3B1.299 (6)
C6—O11.343 (3)C15—O21.310 (4)
C7—N11.268 (3)C15—F2B1.315 (5)
C7—H70.9300C15—F3A1.321 (13)
C8—C91.376 (4)C15—F1B1.357 (6)
C8—C131.392 (4)C15—F2A1.369 (11)
C8—N11.420 (3)O1—H10.91 (5)
C2—C1—C6118.0 (3)C10—C11—H11121.4
C2—C1—C7120.4 (3)C11—C12—F4117.8 (3)
C6—C1—C7121.7 (3)C11—C12—C13124.2 (3)
C3—C2—C1120.7 (3)F4—C12—C13118.0 (3)
C3—C2—H2119.6C12—C13—C8118.4 (3)
C1—C2—H2119.6C12—C13—H13120.8
C2—C3—C4121.0 (3)C8—C13—H13120.8
C2—C3—O2120.5 (3)F1A—C15—F3B119.6 (9)
C4—C3—O2118.3 (3)F1A—C15—O2124.6 (9)
C5—C4—C3119.7 (3)F3B—C15—O2109.3 (6)
C5—C4—H4120.1F1A—C15—F2B69.0 (9)
C3—C4—H4120.1F3B—C15—F2B109.1 (6)
C4—C5—C6120.6 (3)O2—C15—F2B118.6 (4)
C4—C5—H5119.7F1A—C15—F3A103.6 (14)
C6—C5—H5119.7F3B—C15—F3A20.0 (12)
O1—C6—C5118.6 (3)O2—C15—F3A115.9 (14)
O1—C6—C1121.5 (3)F2B—C15—F3A116.6 (14)
C5—C6—C1120.0 (3)F1A—C15—F1B34.5 (8)
N1—C7—C1122.3 (3)F3B—C15—F1B108.4 (5)
N1—C7—H7118.9O2—C15—F1B107.6 (4)
C1—C7—H7118.9F2B—C15—F1B103.5 (5)
C9—C8—C13118.9 (3)F3A—C15—F1B88.4 (11)
C9—C8—N1116.1 (3)F1A—C15—F2A108.5 (10)
C13—C8—N1125.0 (2)F3B—C15—F2A88.4 (8)
C8—C9—C10120.7 (3)O2—C15—F2A96.8 (9)
C8—C9—H9119.7F2B—C15—F2A39.6 (9)
C10—C9—H9119.7F3A—C15—F2A105.7 (12)
C11—C10—C9120.7 (3)F1B—C15—F2A143.0 (10)
C11—C10—H10119.7C7—N1—C8122.9 (2)
C9—C10—H10119.7C6—O1—H1109 (3)
C12—C11—C10117.2 (3)C15—O2—C3117.4 (3)
C12—C11—H11121.4
C6—C1—C2—C31.8 (4)C9—C10—C11—C120.4 (5)
C7—C1—C2—C3178.4 (3)C10—C11—C12—F4178.5 (3)
C1—C2—C3—C41.5 (5)C10—C11—C12—C130.9 (5)
C1—C2—C3—O2177.0 (3)C11—C12—C13—C80.7 (5)
C2—C3—C4—C50.4 (5)F4—C12—C13—C8178.6 (3)
O2—C3—C4—C5176.0 (3)C9—C8—C13—C120.1 (5)
C3—C4—C5—C60.3 (5)N1—C8—C13—C12179.8 (3)
C4—C5—C6—O1179.7 (3)C1—C7—N1—C8179.1 (2)
C4—C5—C6—C10.1 (5)C9—C8—N1—C7178.6 (3)
C2—C1—C6—O1179.3 (3)C13—C8—N1—C71.4 (4)
C7—C1—C6—O10.5 (5)F1A—C15—O2—C339.7 (14)
C2—C1—C6—C51.1 (4)F3B—C15—O2—C3169.1 (5)
C7—C1—C6—C5179.1 (3)F2B—C15—O2—C343.4 (7)
C2—C1—C7—N1179.3 (3)F3A—C15—O2—C3170.4 (13)
C6—C1—C7—N10.5 (4)F1B—C15—O2—C373.4 (6)
C13—C8—C9—C100.3 (5)F2A—C15—O2—C378.4 (11)
N1—C8—C9—C10179.8 (3)C2—C3—O2—C1585.7 (4)
C8—C9—C10—C110.1 (5)C4—C3—O2—C1598.6 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N10.91 (5)1.81 (5)2.618 (3)146 (4)

Experimental details

Crystal data
Chemical formulaC14H9F4NO2
Mr299.22
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)14.223 (2), 7.0894 (6), 13.2479 (19)
β (°) 100.910 (11)
V3)1311.7 (3)
Z4
Radiation typeMo Kα
µ (mm1)0.14
Crystal size (mm)0.72 × 0.34 × 0.07
Data collection
DiffractometerStoe IPDS-II
diffractometer
Absorption correctionIntegration
(X-RED32; Stoe & Cie, 2002)
Tmin, Tmax0.929, 0.985
No. of measured, independent and
observed [I > 2σ(I)] reflections
8512, 2581, 1261
Rint0.063
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.057, 0.133, 1.01
No. of reflections2581
No. of parameters222
No. of restraints66
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.12, 0.14

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).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N10.91 (5)1.81 (5)2.618 (3)146 (4)
 

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 No. F279 of the University Research Fund).

References

First citationCalligaris, M., Nardin, G. & Randaccio, L. (1972). Coord. Chem. Rev. 7, 385–403.  CrossRef CAS Web of Science Google Scholar
First citationCohen, M. D., Schmidt, G. M. J. & Flavian, S. (1964). J. Chem. Soc. pp. 2041–2051.  CrossRef Web of Science Google Scholar
First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
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First citationHadjoudis, E., Vitterakis, M., Moustakali, I. & Mavridis, I. (1987). Tetrahedron, 43, 1345–1360.  CrossRef CAS Web of Science Google Scholar
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