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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 70| Part 1| January 2014| Page o42
https://doi.org/10.1107/S1600536813033278

4-Chloro-2-[(E)-(4-fluoro­phen­yl)imino­meth­yl]phenol

Tian-Jun Fenga*

aCollege of Mathematics and Physics, Lanzhou Jiaotong University, Lanzhou 730070, People's Republic of China
*Correspondence e-mail: fengtj707@126.com

(Received 4 December 2013; accepted 9 December 2013; online 14 December 2013)

In the title Schiff base mol­ecule, C13H9ClFNO, the benzene rings are twisted slightly with respect to each other, making a dihedral angle of 7.92 (2)°. An intra­molecular O—H⋯N hydrogen bond occurs. In the crystal, an infinite chain is formed along the c-axis direction by π–π stacking inter­actions between the phenyl rings and the six-membered hydrogen-bonded ring of neighboring Schiff base ligands [centroid–centroid distances of 3.698 (2) and 3.660 (3) Å]. Neighboring chains are linked into a three-dimensional supra­molecular structure by C—H⋯O and C—H⋯F hydrogen bonds.

CCDC reference: 975729

Related literature

For the coordination modes of Schiff base ligands with transition metals, see: Ebrahimipour et al. (2012[Ebrahimipour, S. Y., Mague, J. T., Akbari, A. & Takjoo, R. (2012). J. Mol. Struct. 1028, 148-155.]); Guo et al. (2013[Guo, H. F., Zhao, X., Ma, D. Y., Xie, A. P. & Shen, W. B. (2013). Transition Met. Chem. 38, 299-305.]). For the biological activity of Schiff base ligands, see: Sawada et al. (2001[Sawada, H., Yanagida, K., Inaba, Y., Sugiya, M., Kawase, T. & Tomita, T. (2001). Eur. Polym. J. 37, 1433-1439.]); Ma et al. (2013[Ma, D. Y., Zhang, L. X., Rao, X. Y., Wu, T. L., Li, D. H. & Xie, X. Q. (2013). J. Coord. Chem. 66, 1486-1496.]); Siddiqui et al. (2006[Siddiqui, J. I., Iqbal, A., Ahmad, S. & Weaver, G. W. (2006). Molecules, 11, 206-211.]).

[Scheme 1]

Experimental

Crystal data

  • C13H9ClFNO

  • Mr = 249.66

  • Monoclinic, P 21 /n

  • a = 4.5140 (9) Å

  • b = 20.560 (4) Å

  • c = 12.0712 (19) Å

  • β = 94.153 (16)°

  • V = 1117.4 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.34 mm−1

  • T = 293 K

  • 0.34 × 0.27 × 0.22 mm
Data collection

  • Agilent Xcalibur (Eos, Gemini) diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011[Agilent (2011). CrysAlis PRO and CrysAlis RED. Agilent Technologies, Yarnton, England.]) Tmin = 0.908, Tmax = 0.942

  • 6481 measured reflections

  • 2016 independent reflections

  • 1143 reflections with I > 2σ(I)

  • Rint = 0.065
Refinement

  • R[F2 > 2σ(F2)] = 0.056

  • wR(F2) = 0.153

  • S = 1.04

  • 2016 reflections

  • 155 parameters

  • H-atom parameters constrained

  • Δρmax = 0.19 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C7—H7⋯O1i 0.93 2.69 3.569 (4) 158
C10—H10⋯F1ii 0.93 2.67 3.481 (4) 147
O1—H1⋯N1 0.82 1.88 2.613 (3) 148
Symmetry codes: (i) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (ii) -x+3, -y+1, -z+2.

Data collection: CrysAlis PRO (Agilent, 2011[Agilent (2011). CrysAlis PRO and CrysAlis RED. Agilent Technologies, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; 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: ORTEPIII (Burnett & Johnson, 1996[Burnett, M. N. & Johnson, C. K. (1996). ORTEPIII. Report ORNL-6895. Oak Ridge National Laboratory, Tennessee, USA.]); software used to prepare material for publication: SHELXL97.

Supporting information

CCDC reference: 975729

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S1600536813033278/zl2572sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536813033278/zl2572Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536813033278/zl2572Isup3.cml

checkCIF report


Comment top

Schiff bases are considered important compounds because of their wide range of biological activities, and also because of their use as ligands in conjunction with transition metals. Schiff base ligands usually coordinate to a metal ion through the imine nitrogen atom, but coordination via other functional groups, e.g. through oxygen or carbon, has also been reported (Ebrahimipour et al., 2012; Guo et al., 2013). Schiff bases derived from salicyladehyde and fluoroaniline, specifically, have been considered as potential pharmaceutically interesting compounds as several of the members of this family of molecules have shown antitumor, antimicrobial or antiviral activities (Sawada et al., 2001; Ma et al., 2013; Siddiqui et al., 2006). As an extension of our work on the structural characterization of Schiff base compounds, the solid state structure of the title compound is reported.

The molecular structure of the title compound shows an E configuration, with a C8—N1=C7—C1 torsion angle of 178.33 (2) °. The bond distance of N1=C7 at 1.276 (3) Å is a typical double bond. It is noteworthy that the H1 atom bonded to O1 is involved in an O1—H1···N1 intramolecular hydrogen bond, which results in the formation of a six-membered ring (Table 1). The dihedral angle between the two planes of the chlorophenol ring and fluorphenyl ring is 7.92 (2) °. An infinite chain is formed by two types of π-π stacking interactions between the phenyl rings (C1—C6 and C8—C13) and the six-membered hydrogen bonded ring (C1/C2/O1/H1/N1/C7) of neighboring Schiff base ligands, with centroid–centroid distances of 3.698 (2) and 3.660 (3) Å, respectively and interplanar spacings of 3.395 (2) Å (Fig. 2a). Finally, neighboring chains are linked into a three-dimensional supramolecular structure by weak C—H···O and C—H···F hydrogen bonding interactions (Fig. 2 b, Table 1).

Related literature top

For the coordination modes of Schiff base ligands with transition metals, see: Ebrahimipour et al. (2012); Guo et al. (2013). For the biological activity of Schiff base ligands, see: Sawada et al. (2001); Ma et al. (2013); Siddiqui et al. (2006).

Experimental top

Title compound was prepared by the condensation of 5-chlorosalicylaldehyde (0.783 g, 5 mmol) and 4-fluoroaniline (0.556 g, 5 mmol) in ethanol (15 ml) as the reaction medium. Glacial acetic acid (0.4 ml) was added and the solution was heated under reflux for 5 h and then allowed to cool to room temperature. The yellow precipitate was recrystallized from ethanol to give the title compound as straw yellow crystals. Yield 0.20 g (80%). [m.p. 361–363 K; IR (KBr, cm-1): 1637(s), 1560(m), 1508(w), 1460(w), 1392(w), 1324(w), 1288(w), 1210(w), 1120(w), 1054(w), 982(w), 932(w), 876(w), 810(w), 747(w), 709(w), 675(w), 564(w), 511(w); 1H NMR (CDCl3, δ, p.p.m.) 13.11 (s, 1H), 8.55 (s, 1H), 6.99–7.39 (m, 7H); 13C NMR (CDCl3, δ, p.p.m.) 161.1, 161.0, 160.7, 159.6, 144.2, 144.1, 133.0, 131.2, 123.8, 122.7, 122.6, 119.9, 118.9, 116.5, 116.2].

Refinement top

H atoms were fixed geometrically and treated as riding with O—H = 0.82 Å (hydroxy) and C—H = 0.93 Å, Uiso(H) = 1.2 Ueq(C) for aromatic H atoms and Uiso(H) = 1.5 Ueq(O) for the hydroxy H atom. The hightest residual electron density peak is located 0.91 Å from H1 and the deepest hole is located 0.91 Å from C13.

Structure description top

Schiff bases are considered important compounds because of their wide range of biological activities, and also because of their use as ligands in conjunction with transition metals. Schiff base ligands usually coordinate to a metal ion through the imine nitrogen atom, but coordination via other functional groups, e.g. through oxygen or carbon, has also been reported (Ebrahimipour et al., 2012; Guo et al., 2013). Schiff bases derived from salicyladehyde and fluoroaniline, specifically, have been considered as potential pharmaceutically interesting compounds as several of the members of this family of molecules have shown antitumor, antimicrobial or antiviral activities (Sawada et al., 2001; Ma et al., 2013; Siddiqui et al., 2006). As an extension of our work on the structural characterization of Schiff base compounds, the solid state structure of the title compound is reported.

The molecular structure of the title compound shows an E configuration, with a C8—N1=C7—C1 torsion angle of 178.33 (2) °. The bond distance of N1=C7 at 1.276 (3) Å is a typical double bond. It is noteworthy that the H1 atom bonded to O1 is involved in an O1—H1···N1 intramolecular hydrogen bond, which results in the formation of a six-membered ring (Table 1). The dihedral angle between the two planes of the chlorophenol ring and fluorphenyl ring is 7.92 (2) °. An infinite chain is formed by two types of π-π stacking interactions between the phenyl rings (C1—C6 and C8—C13) and the six-membered hydrogen bonded ring (C1/C2/O1/H1/N1/C7) of neighboring Schiff base ligands, with centroid–centroid distances of 3.698 (2) and 3.660 (3) Å, respectively and interplanar spacings of 3.395 (2) Å (Fig. 2a). Finally, neighboring chains are linked into a three-dimensional supramolecular structure by weak C—H···O and C—H···F hydrogen bonding interactions (Fig. 2 b, Table 1).

For the coordination modes of Schiff base ligands with transition metals, see: Ebrahimipour et al. (2012); Guo et al. (2013). For the biological activity of Schiff base ligands, see: Sawada et al. (2001); Ma et al. (2013); Siddiqui et al. (2006).

Computing details top

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO (Agilent, 2011); data reduction: CrysAlis PRO (Agilent, 2011); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 30% probability displacement ellipsoids.
[Figure 2] Fig. 2. (a) View of an infinite chain of the title compound formed by π-π stacking interactions (purple dashed lines); (b) View of the three-dimensional supramolecular structure of the title compound formed by C—H···O and C—H···F hydrogen bonds (blue dashed lines).
4-Chloro-2-[(E)-(4-fluorophenyl)iminomethyl]phenol top
Crystal data top
C13H9ClFNOF(000) = 512
Mr = 249.66Dx = 1.484 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 3100 reflections
a = 4.5140 (9) Åθ = 1.7–26.0°
b = 20.560 (4) ŵ = 0.34 mm−1
c = 12.0712 (19) ÅT = 293 K
β = 94.153 (16)°Block, yellow
V = 1117.4 (3) Å30.34 × 0.27 × 0.22 mm
Z = 4
Data collection top
Agilent Xcalibur (Eos, Gemini)
diffractometer		2016 independent reflections
Radiation source: fine-focus sealed tube1143 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.065
ω scansθmax = 25.2°, θmin = 2.6°
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2011)		h = −5→5
Tmin = 0.908, Tmax = 0.942k = −23→24
6481 measured reflectionsl = −14→14
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)] = 0.056Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.153H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0516P)2]
where P = (Fo2 + 2Fc2)/3
2016 reflections(Δ/σ)max < 0.001
155 parametersΔρmax = 0.19 e Å−3
0 restraintsΔρmin = −0.23 e Å−3
Crystal data top
C13H9ClFNOV = 1117.4 (3) Å3
Mr = 249.66Z = 4
Monoclinic, P21/nMo Kα radiation
a = 4.5140 (9) ŵ = 0.34 mm−1
b = 20.560 (4) ÅT = 293 K
c = 12.0712 (19) Å0.34 × 0.27 × 0.22 mm
β = 94.153 (16)°
Data collection top
Agilent Xcalibur (Eos, Gemini)
diffractometer		2016 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2011)		1143 reflections with I > 2σ(I)
Tmin = 0.908, Tmax = 0.942Rint = 0.065
6481 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0560 restraints
wR(F2) = 0.153H-atom parameters constrained
S = 1.04Δρmax = 0.19 e Å−3
2016 reflectionsΔρmin = −0.23 e Å−3
155 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*/Ueq
C10.2601 (7)0.22941 (16)0.7977 (3)0.0364 (8)
C20.1287 (7)0.22602 (17)0.6887 (3)0.0409 (8)
C3−0.0847 (8)0.17908 (18)0.6617 (3)0.0485 (10)
H3−0.17280.17720.58970.058*
C4−0.1685 (8)0.13523 (18)0.7395 (3)0.0480 (9)
H4−0.31120.10380.72020.058*
C5−0.0384 (8)0.13834 (17)0.8465 (3)0.0462 (9)
C60.1714 (7)0.18464 (16)0.8761 (3)0.0456 (9)
H60.25520.18630.94880.055*
C70.4848 (7)0.27750 (17)0.8303 (3)0.0420 (9)
H70.56990.27720.90280.050*
C80.7834 (7)0.36833 (16)0.7949 (3)0.0380 (8)
C90.8940 (7)0.37974 (17)0.9038 (3)0.0477 (9)
H90.83100.35400.96100.057*
C101.0968 (8)0.42908 (17)0.9277 (3)0.0517 (10)
H101.16980.43701.00050.062*
C111.1880 (8)0.46601 (17)0.8424 (3)0.0487 (9)
C121.0866 (8)0.45657 (18)0.7349 (3)0.0524 (10)
H121.15260.48240.67850.063*
C130.8819 (8)0.40728 (17)0.7116 (3)0.0494 (10)
H130.80930.40020.63850.059*
Cl1−0.1447 (3)0.08228 (5)0.94489 (9)0.0769 (4)
F11.3866 (5)0.51483 (10)0.86620 (19)0.0767 (7)
N10.5694 (6)0.32018 (13)0.7626 (2)0.0407 (7)
O10.2061 (6)0.26776 (13)0.60954 (19)0.0573 (7)
H10.32900.29370.63660.086*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0361 (18)0.039 (2)0.0332 (19)0.0018 (16)−0.0011 (15)−0.0019 (16)
C20.044 (2)0.043 (2)0.035 (2)−0.0010 (17)0.0013 (16)−0.0047 (17)
C30.052 (2)0.054 (2)0.038 (2)0.0012 (19)−0.0047 (18)−0.0142 (19)
C40.048 (2)0.044 (2)0.051 (2)−0.0036 (18)0.0013 (19)−0.0134 (19)
C50.053 (2)0.041 (2)0.044 (2)−0.0051 (18)0.0023 (18)−0.0012 (17)
C60.051 (2)0.048 (2)0.037 (2)0.0005 (18)−0.0034 (17)−0.0033 (18)
C70.0398 (19)0.046 (2)0.039 (2)0.0023 (17)−0.0052 (16)−0.0055 (18)
C80.0378 (19)0.036 (2)0.039 (2)0.0013 (15)−0.0008 (16)−0.0005 (17)
C90.052 (2)0.048 (2)0.043 (2)−0.0075 (18)0.0015 (18)−0.0019 (18)
C100.059 (2)0.049 (2)0.045 (2)−0.0026 (19)−0.0100 (19)−0.0030 (19)
C110.045 (2)0.042 (2)0.058 (3)−0.0080 (17)−0.0024 (19)−0.004 (2)
C120.056 (2)0.049 (2)0.053 (2)−0.005 (2)0.007 (2)0.0058 (19)
C130.052 (2)0.053 (2)0.042 (2)0.0011 (19)−0.0058 (18)0.0001 (19)
Cl10.0965 (9)0.0668 (8)0.0659 (7)−0.0274 (6)−0.0031 (6)0.0137 (6)
F10.0852 (16)0.0563 (15)0.0870 (17)−0.0318 (13)−0.0043 (13)−0.0019 (13)
N10.0397 (16)0.0414 (17)0.0407 (17)−0.0025 (14)0.0010 (13)−0.0040 (15)
O10.0689 (19)0.0628 (18)0.0385 (14)−0.0163 (14)−0.0068 (13)0.0018 (14)
Geometric parameters (Å, º) top
C1—C61.400 (4)C8—C131.384 (4)
C1—C21.406 (4)C8—C91.392 (4)
C1—C71.450 (4)C8—N11.418 (4)
C2—O11.349 (4)C9—C101.383 (5)
C2—C31.385 (4)C9—H90.9300
C3—C41.374 (5)C10—C111.366 (5)
C3—H30.9300C10—H100.9300
C4—C51.381 (5)C11—C121.359 (5)
C4—H40.9300C11—F11.362 (4)
C5—C61.372 (4)C12—C131.386 (5)
C5—Cl11.747 (4)C12—H120.9300
C6—H60.9300C13—H130.9300
C7—N11.276 (4)O1—H10.8200
C7—H70.9300
C6—C1—C2118.6 (3)C13—C8—C9118.5 (3)
C6—C1—C7119.6 (3)C13—C8—N1116.9 (3)
C2—C1—C7121.8 (3)C9—C8—N1124.6 (3)
O1—C2—C3119.2 (3)C10—C9—C8120.5 (3)
O1—C2—C1121.2 (3)C10—C9—H9119.8
C3—C2—C1119.5 (3)C8—C9—H9119.8
C4—C3—C2121.2 (3)C11—C10—C9118.8 (3)
C4—C3—H3119.4C11—C10—H10120.6
C2—C3—H3119.4C9—C10—H10120.6
C3—C4—C5119.3 (3)C12—C11—F1118.5 (3)
C3—C4—H4120.4C12—C11—C10122.8 (4)
C5—C4—H4120.4F1—C11—C10118.7 (3)
C6—C5—C4121.0 (3)C11—C12—C13118.1 (4)
C6—C5—Cl1119.9 (3)C11—C12—H12120.9
C4—C5—Cl1119.1 (3)C13—C12—H12120.9
C5—C6—C1120.4 (3)C8—C13—C12121.3 (3)
C5—C6—H6119.8C8—C13—H13119.3
C1—C6—H6119.8C12—C13—H13119.3
N1—C7—C1122.1 (3)C7—N1—C8122.3 (3)
N1—C7—H7119.0C2—O1—H1109.5
C1—C7—H7119.0
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C7—H7···O1i0.932.693.569 (4)158
C10—H10···F1ii0.932.673.481 (4)147
O1—H1···N10.821.882.613 (3)148
Symmetry codes: (i) x+1/2, −y+1/2, z+1/2; (ii) −x+3, −y+1, −z+2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C7—H7···O1i0.932.693.569 (4)157.8
C10—H10···F1ii0.932.673.481 (4)146.5
O1—H1···N10.821.882.613 (3)147.5
Symmetry codes: (i) x+1/2, −y+1/2, z+1/2; (ii) −x+3, −y+1, −z+2.
 

Acknowledgements

The author acknowledges Lanzhou Jiaotong University for supporting this work.

References

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 First citationBurnett, M. N. & Johnson, C. K. (1996). ORTEPIII. Report ORNL-6895. Oak Ridge National Laboratory, Tennessee, USA.  Google Scholar
 First citationEbrahimipour, S. Y., Mague, J. T., Akbari, A. & Takjoo, R. (2012). J. Mol. Struct. 1028, 148–155.  Google Scholar
 First citationGuo, H. F., Zhao, X., Ma, D. Y., Xie, A. P. & Shen, W. B. (2013). Transition Met. Chem. 38, 299–305.  Web of Science CSD CrossRef CAS Google Scholar
 First citationMa, D. Y., Zhang, L. X., Rao, X. Y., Wu, T. L., Li, D. H. & Xie, X. Q. (2013). J. Coord. Chem. 66, 1486–1496.  Web of Science CSD CrossRef CAS Google Scholar
 First citationSawada, H., Yanagida, K., Inaba, Y., Sugiya, M., Kawase, T. & Tomita, T. (2001). Eur. Polym. J. 37, 1433–1439.  Web of Science CrossRef CAS Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationSiddiqui, J. I., Iqbal, A., Ahmad, S. & Weaver, G. W. (2006). Molecules, 11, 206–211.  Web of Science CrossRef PubMed CAS Google Scholar

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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 70| Part 1| January 2014| Page o42
https://doi.org/10.1107/S1600536813033278
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